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Jiang X, Yang T, He F, Zhang F, Jiang X, Wang C, Gao T, Long R, Li M, Yang Q, Wang Y, Zhang T, Kang J. A genome-wide association study reveals novel loci and candidate genes associated with plant height variation in Medicago sativa. BMC PLANT BIOLOGY 2024; 24:544. [PMID: 38872112 DOI: 10.1186/s12870-024-05151-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Accepted: 05/15/2024] [Indexed: 06/15/2024]
Abstract
BACKGROUND Plant height (PH) is an important agronomic trait influenced by a complex genetic network. However, the genetic basis for the variation in PH in Medicago sativa remains largely unknown. In this study, a comprehensive genome-wide association analysis was performed to identify genomic regions associated with PH using a diverse panel of 220 accessions of M. sativa worldwide. RESULTS Our study identified eight novel single nucleotide polymorphisms (SNPs) significantly associated with PH evaluated in five environments, explaining 8.59-12.27% of the phenotypic variance. Among these SNPs, the favorable genotype of chr6__31716285 had a low frequency of 16.4%. Msa0882400, located proximal to this SNP, was annotated as phosphate transporter 3;1, and its role in regulating alfalfa PH was supported by transcriptome and candidate gene association analysis. In addition, 21 candidate genes were annotated within the associated regions that are involved in various biological processes related to plant growth and development. CONCLUSIONS Our findings provide new molecular markers for marker-assisted selection in M. sativa breeding programs. Furthermore, this study enhances our understanding of the underlying genetic and molecular mechanisms governing PH variations in M. sativa.
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Affiliation(s)
- Xueqian Jiang
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Tianhui Yang
- Institute of Animal Science, Ningxia Academy of Agricultural and Forestry Sciences, Yinchuan, Ningxia, China
- Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot, Inner Mongolia, China
| | - Fei He
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fan Zhang
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xu Jiang
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Chuan Wang
- Institute of Animal Science, Ningxia Academy of Agricultural and Forestry Sciences, Yinchuan, Ningxia, China
| | - Ting Gao
- Institute of Animal Science, Ningxia Academy of Agricultural and Forestry Sciences, Yinchuan, Ningxia, China
| | - Ruicai Long
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Mingna Li
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Qingchuan Yang
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yue Wang
- Beijing NO.19 High School, Beijing, China
| | - Tiejun Zhang
- School of Grassland Science, Beijing Forestry University, Beijing, China.
| | - Junmei Kang
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China.
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Singh B, Muthusamy V, Shrivastava S, Chand G, Gain N, Bhatt V, Zunjare RU, Hossain F. Analysis of nutritional composition in opaque2- and crtRB1-based single- and double-biofortified super sweet corn. J Appl Genet 2024:10.1007/s13353-024-00873-0. [PMID: 38733523 DOI: 10.1007/s13353-024-00873-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 04/22/2024] [Accepted: 04/23/2024] [Indexed: 05/13/2024]
Abstract
Sweet corn has emerged as a favorite food item worldwide owing to its kernel sweetness. However, traditional sweet corn cultivars are poor in provitamin-A (proA) and essential amino acids, viz., lysine and tryptophan. So far, no sweet corn hybrid with high nutritional qualities has been commercialized elsewhere. Here, we analyzed accumulation of provitamin-A (proA), lysine, and tryptophan in a set of mutant versions of (i) crtRB1-, (ii) o2-, and (iii) crtRB1 + o2-based sweet corn inbreds and hybrids with (iv) traditional sweet corn (wild-type: O2 + CrtRB1). The crtRB1- and crtRB1 + o2-based genotypes possessed significantly higher proA (17.31 ppm) over traditional sweet corn (2.83 ppm), while o2- and crtRB1 + o2-based genotypes possessed significantly higher lysine (0.345%) and tryptophan (0.080%) over traditional sweet corn (lysine 0.169%, tryptophan 0.036%). Late sowing favored high kernel lysine, proA, and green cob yield among hybrids. Sweetness (17.87%) among the improved inbreds and hybrids was comparable to the original sweetcorn genotypes (17.84%). Among the four genotypic classes, crtRB1 + o2-based improved genotypes showed stronger association among traits over genotypes with o2 and crtRB1 genes alone. Significant association was observed among (i) proA and BC (r = 0.99), (ii) proA and BCX (r = 0.93), (iii) lysine and tryptophan (r = 0.99), and (iv) green cob yield with fodder yield (r = 0.73) in sweet corn hybrids. The study demonstrated that combining crtRB1 and o2 genes did not pose any negative impact on nutritional, yield, and agronomic performance. Sweet corn with crtRB1 + o2 assumes significance for alleviating malnutrition through sustainable and cost-effective approach.
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Affiliation(s)
- Bhavna Singh
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
- Amity Institute of Biotechnology, Amity University, Noida, India
| | - Vignesh Muthusamy
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | | | - Gulab Chand
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Nisrita Gain
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Vinay Bhatt
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Rajkumar U Zunjare
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Firoz Hossain
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India.
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Mehta BK, Chauhan HS, Basu S, Anand A, Baveja A, Zunjare RU, Muthusamy V, Singh AK, Hossain F. Mutant crtRB1 gene negates the unfavourable effects of opaque2 gene on germination and seed vigour among shrunken2-based biofortified sweet corn genotypes. FUNCTIONAL PLANT BIOLOGY : FPB 2024; 51:FP23179. [PMID: 38326234 DOI: 10.1071/fp23179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 01/18/2024] [Indexed: 02/09/2024]
Abstract
Sweet corn is one of the most popular vegetables worldwide. However, traditional shrunken2 (sh2 )-based sweet corn varieties are poor in nutritional quality. Here, we analysed the effect of (1) β-carotene hydroxylase1 (crtRB1 ), (2) opaque2 (o2 ) and (3) o2+crtRB1 genes on nutritional quality, germination, seed vigour and physico-biochemical traits in a set of 27 biofortified sh2 -based sweet corn inbreds. The biofortified sweet corn inbreds recorded significantly higher concentrations of proA (16.47μg g-1 ), lysine (0.36%) and tryptophan (0.09%) over original inbreds (proA: 3.14μg g-1 , lysine: 0.18%, tryptophan: 0.04%). The crtRB1 -based inbreds had the lowest electrical conductivity (EC), whereas o2 -based inbreds possessed the highest EC. The o2 +crtRB1 -based inbreds showed similar EC to the original inbreds. Interestingly, o2 -based inbreds also had the lowest germination and seed vigour compared to original inbreds, whereas crtRB1 and o2 +crtRB1 introgressed sweet corn inbreds showed similar germination and seed vigour traits to their original versions. This suggested that the negative effect of o2 on germination, seed vigour and EC is nullified by crtRB1 in the double mutant sweet corn. Overall, o2 +crtRB1 -based sweet corn inbreds were found the most desirable over crtRB1 - and o2 -based inbreds alone.
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Affiliation(s)
- Brijesh K Mehta
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; and Present address: ICAR-Indian Grassland and Fodder Research Institute, Jhansi 284003, India
| | - Hema S Chauhan
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Sudipta Basu
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Anjali Anand
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Aanchal Baveja
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | | | - Vignesh Muthusamy
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Ashok K Singh
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Firoz Hossain
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
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Talukder ZA, Chhabra R, Muthusamy V, Zunjare RU, Hossain F. Development of novel gene-based markers for waxy1 gene and their validation for exploitation in molecular breeding for enhancement of amylopectin in maize. J Appl Genet 2023; 64:409-418. [PMID: 37269444 DOI: 10.1007/s13353-023-00762-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 05/01/2023] [Accepted: 05/19/2023] [Indexed: 06/05/2023]
Abstract
Waxy corn possessing high amylopectin is widely employed as an industrial product. Traditional corn contains ~ 70-75% amylopectin, whereas waxy corn with the mutant waxy1 (wx1) gene possesses ~ 95-100% amylopectin. Marker-assisted breeding can greatly hasten the transfer of the wx1 allele into normal corn. However, the available gene-based marker(s) for wx1 are not always polymorphic between recipient and donor parents, thereby causing a considerable delay in the molecular breeding program. Here, a 4800 bp sequence of the wx1 gene was analyzed among seven wild-type and seven mutant inbreds employing 16 overlapping primers. Three polymorphisms viz., 4 bp InDel (at position 2406 bp) in intron-7 and two SNPs (C to A at position 3325 bp in exon-10 and G to T at position 4310 bp in exon-13) differentiated the dominant (Wx1) and recessive (wx1) allele. Three breeder-friendly PCR markers (WxDel4, SNP3325_CT1, and SNP4310_GT2) specific to InDel and SNPs were developed. WxDel4 amplified 94 bp among mutant-type inbreds, while 90 bp was amplified among wild-type inbreds. SNP3325_CT1 and SNP4310_GT2 revealed the presence-absence polymorphisms with an amplification of 185 bp and 189 bp of amplicon, respectively. These newly developed markers showed 1:1 segregation in both BC1F1 and BC2F1 generations, while 1:2:1 segregation was observed in BC2F2. The recessive homozygotes (wx1wx1) of BC2F2 identified by the markers possessed significantly higher amylopectin (97.7%) compared to the original inbreds (Wx1Wx1: 72.7% amylopectin). This is the first report of novel wx1 gene-based markers. The information generated here would help in accelerating the development of waxy maize hybrids.
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Affiliation(s)
| | - Rashmi Chhabra
- ICAR-Indian Agricultural Research Institute, New Delhi, India
| | | | | | - Firoz Hossain
- ICAR-Indian Agricultural Research Institute, New Delhi, India.
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5
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Hossain F, Jaiswal SK, Muthusamy V, Zunjare RU, Mishra SJ, Chand G, Bhatt V, Bhat JS, Das AK, Chauhan HS, Gupta HS. Enhancement of nutritional quality in maize kernel through marker-assisted breeding for vte4, crtRB1, and opaque2 genes. J Appl Genet 2023; 64:431-443. [PMID: 37450243 DOI: 10.1007/s13353-023-00768-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 05/31/2023] [Accepted: 06/19/2023] [Indexed: 07/18/2023]
Abstract
Traditional maize is poor in vitamin-E [α-tocopherol (α-T): 6-8 ppm], vitamin-A [provitamin-A (proA): 1-2ppm], lysine (0.150-0.2-50%), and tryptophan (0.030-0.040%). Here, we combined favourable alleles of vte4, crtRB1, and opaque2 (o2) genes in the parents of maize hybrids, viz., APQH-10 (PMI-PV-9 × PMI-PV-14) and APQH-11 (PMI-PV-9 × PMI-PV-15) using molecular breeding. Gene-specific markers were successfully used to select vte4, crtRB1, and o2 in BC1F1, BC2F1, and BC2F2 generations. Simple sequence repeats (104-109) were used for background selection, leading to an average recovery of 94% recurrent parent genome. The introgressed inbreds possessed significantly higher α-T: 18.38 ppm, α-/γ-tocopherol (α-/γ-T: 52%), and α-/total tocopherol (α-/TT: 32%) compared to original inbreds (α-T: 8.17 ppm, α-/γ-T: 25%, α-/TT: 18%). These newly derived inbreds also possessed higher β-carotene (BC: 8.91 ppm), β-cryptoxanthin (BCX: 1.27 ppm), proA (9.54 ppm), lysine (0.348%), and tryptophan (0.082%) compared to traditional maize inbreds. The reconstituted hybrids recorded higher α-T (2.1-fold), α-/γ-T (1.9-fold), and α-/TT (1.6-fold) over the original hybrids. These reconstituted hybrids were also rich in BC (5.7-fold), BCX (3.3-fold), proA (5.3-fold), lysine (1.9-fold), and tryptophan (2.0-fold) over the traditional hybrids. The reconstituted hybrids had similar grain yield and phenotypic characteristics to original versions. These multinutrient-rich maize hybrids hold great potential to alleviate malnutrition in sustainable and cost-effective manner.
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Affiliation(s)
- Firoz Hossain
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
| | - Sunil K Jaiswal
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Vignesh Muthusamy
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Rajkumar U Zunjare
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Subhra J Mishra
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Gulab Chand
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Vinay Bhatt
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Jayant S Bhat
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Abhijit K Das
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Hema S Chauhan
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Hari S Gupta
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
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6
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Bhatt V, Muthusamy V, Panda KK, Katral A, Chhabra R, Mishra SJ, Gopinath I, Zunjare RU, Neeraja CN, Rakshit S, Yadava DK, Hossain F. Expression Dynamics of lpa1 Gene and Accumulation Pattern of Phytate in Maize Genotypes Possessing opaque2 and crtRB1 Genes at Different Stages of Kernel Development. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12091745. [PMID: 37176803 PMCID: PMC10180721 DOI: 10.3390/plants12091745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 04/21/2023] [Accepted: 04/21/2023] [Indexed: 05/15/2023]
Abstract
Phytic acid (PA) acts as a storehouse for the majority of the mineral phosphorous (P) in maize; ~80% of the total P stored as phytate P is not available to monogastric animals and thereby causes eutrophication. In addition, phytic acid chelates positively charged minerals making them unavailable in the diet. The mutant lpa1-1 allele reduces PA more than the wild-type LPA1 allele. Further, mutant gene opaque2 (o2) enhances lysine and tryptophan and crtRB1 enhances provitamin-A (proA) more than wild-type O2 and CRTRB1 alleles, respectively. So far, the expression pattern of the mutant lpa1-1 allele has not been analysed in maize genotypes rich in lysine, tryptophan and proA. Here, we analysed the expression pattern of wild and mutant alleles of LPA1, O2 and CRTRB1 genes in inbreds with (i) mutant lpa1-1, o2 and crtRB1 alleles, (ii) wild-type LPA1 allele and mutant o2 and crtRB1 alleles and (iii) wild-type LPA1, O2 and CRTRB1 alleles at 15, 30 and 45 days after pollination (DAP). The average reduction of PA/total phosphorous (TP) in lpa1-1 mutant inbreds was 29.30% over wild-type LPA1 allele. The o2 and crtRB1-based inbreds possessed ~two-fold higher amounts of lysine and tryptophan, and four-fold higher amounts of proA compared to wild-type alleles. The transcript levels of lpa1-1, o2 and crtRB1 genes in lpa1-1-based inbreds were significantly lower than their wild-type versions across kernel development. The lpa1-1, o2 and crtRB1 genes reached their highest peak at 15 DAP. The correlation of transcript levels of lpa1-1 was positive for PA/TP (r = 0.980), whereas it was negative with inorganic phosphorous (iP) (r = -0.950). The o2 and crtRB1 transcripts showed negative correlations with lysine (r = -0.887) and tryptophan (r = -0.893), and proA (r = -0.940), respectively. This is the first comprehensive study on lpa1-1 expression in the maize inbreds during different kernel development stages. The information generated here offers great potential for comprehending the dynamics of phytic acid regulation in maize.
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Affiliation(s)
- Vinay Bhatt
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
- AMITY Institute of Biotechnology, AMITY University, Noida 201313, Uttar Pradesh, India
| | - Vignesh Muthusamy
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Kusuma Kumari Panda
- AMITY Institute of Biotechnology, AMITY University, Noida 201313, Uttar Pradesh, India
| | - Ashvinkumar Katral
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Rashmi Chhabra
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Subhra J Mishra
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Ikkurti Gopinath
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Rajkumar U Zunjare
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | | | - Sujay Rakshit
- ICAR-Indian Institute of Maize Research, Ludhiana 141004, India
- ICAR-Indian Institute of Agricultural Biotechnology, Ranchi 834010, India
| | - Devendra K Yadava
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Firoz Hossain
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
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Singh B, Zunjare RU, Shrivastava S, Chand G, Gain N, Bhatt V, Muthusamy V, Hossain F. Provitamin A, lysine and tryptophan enrichment in shrunken2-based sweet corn genotypes through genomics-assisted breeding for crtRB1 and opaque2 genes. Mol Biol Rep 2023; 50:4965-4974. [PMID: 37083988 DOI: 10.1007/s11033-023-08446-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 04/12/2023] [Indexed: 04/22/2023]
Abstract
BACKGROUND Malnutrition affects large section of population worldwide. Vitamin A and protein deficiencies have emerged as the major global health-issue. Traditional shrunken2 (sh2)-based sweet corn is deficient in provitamin A (proA), lysine and tryptophan. Natural variant of β-carotene hydroxylase1 (crtRB1) and opaque2 (o2) enhances proA, lysine and tryptophan in maize. So far, no sweet corn hybrid rich in these nutrients has been released elsewhere. Development of biofortified sweet corn hybrids would help in providing the balanced nutrition. METHODS AND RESULTS We targeted three sh2-based sweet corn inbreds (SWT-19, SWT-20 and SWT-21) for introgression of mutant crtRB1 and o2 genes using molecular breeding. The gene-based 3'TE-InDel and simple sequence repeat (SSR) (umc1066) markers specific to crtRB1 and o2, respectively were utilized in foreground selection in BC1F1, BC2F1 and BC2F2. Segregation distortion was observed for crtRB1 and o2 genes in majority of populations. Background selection using 91-100 SSRs revealed recovery of recurrent parent genome (RPG) up to 96%. The introgressed progenies possessed significantly higher proA (13.56 µg/g) as compared to the original versions (proA: 2.70 µg/g). Further, the introgressed progenies had accumulated moderately higher level of lysine (0.336%) and tryptophan (0.082%) over original versions (lysine: 0.154% and tryptophan: 0.038%). Kernel sweetness among introgressed progenies (17.3%) was comparable to original sweet corn (17.4%). The introgressed inbreds exhibited higher resemblance with their recurrent parents for yield and morphological characters. CONCLUSION These newly developed biofortified sweet corn genotypes hold immense promise to alleviate malnutrition.
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Affiliation(s)
- Bhavna Singh
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
- Amity Institute of Biotechnology, Amity University, Noida, India
| | - Rajkumar U Zunjare
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | | | - Gulab Chand
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Nisrita Gain
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Vinay Bhatt
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Vignesh Muthusamy
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Firoz Hossain
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India.
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Amegbor IK, van Biljon A, Shargie NG, Tarekegne A, Labuschagne MT. Combining ability estimates for quality and non-quality protein maize inbred lines for grain yield, agronomic, and quality traits. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2023. [DOI: 10.3389/fsufs.2023.1123224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023] Open
Abstract
IntroductionBiofortified maize varieties could contribute to the fight against hunger and malnutrition of the increasing human population and help meet the high demand of maize for human consumption, industrial use and feed for animal and poultry. The understanding of the genetic mechanisms conditioning the inheritance of grain yield and other agronomic and quality traits is essential in the development of superior maize genotypes. The main objective of this study was to determine the combining ability for grain yield and other agronomic traits of QPM and non-QPM inbred lines crossed with two QPM and two non-QPM testers.Materials and methodsA total of 130 hybrids were obtained by crossing 10 non-QPM and 23 QPM lines with four elite testers (two QPM and two non-QPM). The 130 single cross hybrids were evaluated at 13 sites in 2018 and 2019.Results and discussionThe results showed significant general combining ability (GCA) for lines and testers as well as significant specific combining ability (SCA) for hybrids for most of the measured traits. Non-additive gene action controlled the inheritance of grain yield while agronomic and quality traits were controlled by additive gene action. QPM lines 11, 14 and 28 and non-QPM tester CML444 showed desirable GCA effects for grain yield, indicating that these lines in combination with tester CML444 should be considered when targeting development of superior maize genotypes with QPM traits.ConclusionsBased on the SCA values, crosses 120, 108, 105, 99, 85, and 41 were identified as the best hybrids across the locations. It is recommended that maize breeding programs targeting the development of high yielding QPM hybrids should exploit QPM lines with high GCA values for heterosis to be realized. In addition, the identified superior hybrids may be further evaluated and consequently promoted for commercial release which could increase incomes of farmers and help to alleviate poverty, hunger and malnutrition in southern Africa and sub-Saharan Africa at large.
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Saha I, Rathinavel K, Manoharan B, Adhimoolam K, Sampathrajan V, Rajasekaran R, Muthurajan R, Natesan S. The resurrection of sweet corn inbred SC11-2 using marker aided breeding for β-carotene. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2022. [DOI: 10.3389/fsufs.2022.1004450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Sweet corn has dominated the urban market due to its sweetness, tenderness, and ease of digestibility. It's import and export values have dramatically increased during the past 10 years as a fresh, processed, and preserved commodity. However, the commercially available sweet corns are deficient in β-carotene. In our study, we introgressed the favorable allele of crtRB1 (responsible for high β-carotene) into the recurrent sweet corn inbred SC11-2 from maize donor parent UMI1230β1+ to develop the β-carotene-rich sweet corn genotype by marker aided breeding. The crtRB1 3′TE InDel marker was utilized for foreground selection of favorable genotype. A total of 103 polymorphic SSR markers were employed for background selection, resulting in a 96% recovery of recurrent parent genome (RPG). We recorded high β-carotene content (9.878–10.645 μg/g) in the introgressed lines compared to the recurrent parent, SC11-2 (0.989 μg/g). The sugar content ranged from 18 to 19.10% and was on par with the recurrent parent (20.40%). These biofortified inbreds can be used as a donor in maize breeding programs to develop sweet corn genotypes with high β-carotene content.
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10
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Chand G, Zunjare RU, Allen T, Muthusamy V, Mishra SJ, Kasana RK, Bhatt V, Ismail MR, Sarika K, Guleria SK, Hossain F. Genetic analysis of maize genotypes possessing novel combination of opaque2 and opaque16 genes affecting higher accumulation of lysine and tryptophan in kernels. J Cereal Sci 2022. [DOI: 10.1016/j.jcs.2022.103534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11
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Grain quality and yield potential of hybrids from quality and non-quality protein maize inbred lines. J Cereal Sci 2022. [DOI: 10.1016/j.jcs.2022.103544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Development of β-carotene, lysine, and tryptophan-rich maize (Zea mays) inbreds through marker-assisted gene pyramiding. Sci Rep 2022; 12:8551. [PMID: 35595742 PMCID: PMC9123160 DOI: 10.1038/s41598-022-11585-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 04/05/2022] [Indexed: 11/08/2022] Open
Abstract
Maize (Zea mays L.) is the leading cereal crop and staple food in many parts of the world. This study aims to develop nutrient-rich maize genotypes by incorporating crtRB1 and o2 genes associated with increased β-carotene, lysine, and tryptophan levels. UMI1200 and UMI1230, high quality maize inbreds, are well-adapted to tropical and semi-arid regions in India. However, they are deficient in β-carotene, lysine, and tryptophan. We used the concurrent stepwise transfer of genes by marker-assisted backcross breeding (MABB) scheme to introgress crtRB1 and o2 genes. In each generation (from F1, BC1F1-BC3F1, and ICF1-ICF3), foreground and background selections were carried out using gene-linked (crtRB1 3'TE and umc1066) and genome-wide simple sequence repeats (SSR) markers. Four independent BC3F1 lines of UMI1200 × CE477 (Cross-1), UMI1200 × VQL1 (Cross-2), UMI1230 × CE477 (Cross-3), and UMI1230 × VQL1 (Cross-4) having crtRB1 and o2 genes and 87.45-88.41% of recurrent parent genome recovery (RPGR) were intercrossed to generate the ICF1-ICF3 generations. Further, these gene pyramided lines were examined for agronomic performance and the β-carotene, lysine, and tryptophan contents. Six ICF3 lines (DBT-IC-β1σ4-4-8-8, DBT-IC-β1σ4-9-21-21, DBT-IC-β1σ4-10-1-1, DBT-IC-β2σ5-9-51-51, DBT-IC-β2σ5-9-52-52 and DBT-IC-β2σ5-9-53-53) possessing crtRB1 and o2 genes showed better agronomic performance (77.78-99.31% for DBT-IC-β1σ4 population and 85.71-99.51% for DBT-IC-β2σ5 population) like the recurrent parents and β-carotene (14.21-14.35 μg/g for DBT-IC-β1σ4 and 13.28-13.62 μg/g for DBT-IC-β2σ5), lysine (0.31-0.33% for DBT-IC-β1σ4 and 0.31-0.34% for DBT-IC-β2σ5), and tryptophan (0.079-0.082% for DBT-IC-β1σ4 and 0.078-0.083% for DBT-IC-β2σ5) levels on par with that of the donor parents. In the future, these improved lines could be developed as a cultivar for various agro-climatic zones and also as good genetic materials for maize nutritional breeding programs.
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Baveja A, Chhabra R, Panda KK, Muthusamy V, Mehta BK, Mishra SJ, Zunjare RU, Hossain F. Expression analysis of opaque2, crtRB1 and shrunken2 genes during different stages of kernel development in biofortified sweet corn. J Cereal Sci 2022. [DOI: 10.1016/j.jcs.2022.103466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Composition of lysine and tryptophan among biofortified-maize possessing novel combination of opaque2 and opaque16 genes. J Food Compost Anal 2022. [DOI: 10.1016/j.jfca.2021.104376] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Amegbor I, van Biljon A, Shargie N, Tarekegne A, Labuschagne M. Identifying Quality Protein Maize Inbred Lines for Improved Nutritional Value of Maize in Southern Africa. Foods 2022; 11:foods11070898. [PMID: 35406985 PMCID: PMC8998117 DOI: 10.3390/foods11070898] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/14/2022] [Accepted: 03/17/2022] [Indexed: 12/10/2022] Open
Abstract
Malnutrition, as a result of deficiency in essential nutrients in cereal food products and consumption of a poorly balanced diet, is a major challenge facing millions of people in developing countries. However, developing maize inbred lines that are high yielding with enhanced nutritional traits for hybrid development remains a challenge. This study evaluated 40 inbred lines: 26 quality protein maize (QPM) lines, nine non-QPM lines, and five checks (three QPM lines and two non-QPM lines) in four optimum environments in Zimbabwe and South Africa. The objective of the study was to identify good-quality QPM inbred lines for future hybrid breeding efforts in order to increase the nutritional value of maize. The QPM lines had a lower protein content (7% lower) than that of the non-QPM lines but had 1.9 times more tryptophan and double the quality index. The lysine- and tryptophan-poor α-zein protein fraction was 41% lower in QPM than in non-QPM, with a subsequent increase in γ-zein. There was significant variation within the QPM inbred lines for all measured quality characteristics, indicating that the best lines can be selected from this material without a yield penalty. QPM lines that had both high protein and tryptophan levels, which can be used as parents for highly nutritious hybrids, were identified.
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Affiliation(s)
- Isaac Amegbor
- Department of Plant Sciences, University of the Free State, Bloemfontein 9300, South Africa; (I.A.); (A.v.B.)
- CSIR—Savanna Agricultural Research Institute, Tamale 00233, Ghana
| | - Angeline van Biljon
- Department of Plant Sciences, University of the Free State, Bloemfontein 9300, South Africa; (I.A.); (A.v.B.)
| | - Nemera Shargie
- Agricultural Research Council—Grain Crops, Potchefstroom 2520, South Africa;
| | | | - Maryke Labuschagne
- Department of Plant Sciences, University of the Free State, Bloemfontein 9300, South Africa; (I.A.); (A.v.B.)
- Correspondence: ; Tel.: +27-51-4012-715
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Amegbor IK, van Biljon A, Shargie N, Tarekegne A, Labuschagne MT. Heritability and Associations among Grain Yield and Quality Traits in Quality Protein Maize (QPM) and Non-QPM Hybrids. PLANTS (BASEL, SWITZERLAND) 2022; 11:713. [PMID: 35336595 PMCID: PMC8951685 DOI: 10.3390/plants11060713] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/22/2022] [Accepted: 02/24/2022] [Indexed: 06/14/2023]
Abstract
Maize (Zea mays L.) is the main staple cereal food crop cultivated in southern Africa. Interactions between grain yield and biochemical traits can be useful to plant breeders in making informed decisions on the traits to be considered in breeding programs for high grain yield and enhanced quality. The objectives of this study were to estimate the heritability of grain yield and its related traits, as well as quality traits, and determine the association between quality protein maize (QPM) with non-QPM crosses. Grain yield, and agronomic and quality trait data were obtained from 13 field trials in two countries, for two consecutive seasons. Significant genotypic and phenotypic correlations were recorded for grain yield with protein content (rG = 0.38; rP = 0.25), and tryptophan with oil content (rG = 0.58; rP = 0.25), and negative rG and rP correlations were found for protein with tryptophan content and grain yield with tryptophan content. Path analysis identified ear aspect, ears per plant, and starch as the major traits contributing to grain yield. It is recommended that ear aspect should be considered a key secondary trait in breeding for QPM hybrids. The negative association between grain yield and tryptophan, and between protein and tryptophan, will make it difficult to develop hybrids with high grain yield and high tryptophan content. Hence, it is recommended that gene pyramiding should be considered for these traits.
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Affiliation(s)
- Isaac Kodzo Amegbor
- Department of Plant Sciences, University of the Free State, Bloemfontein 9301, South Africa;
- Maize Improvement Programme, CSIR-Savanna Agricultural Research Institute, Tamale P.O. Box TL 52, Ghana
| | - Angeline van Biljon
- Department of Plant Sciences, University of the Free State, Bloemfontein 9301, South Africa;
| | - Nemera Shargie
- ARC—Grain Crops Institute, Private Bag X1251, Potchefstroom 2520, South Africa;
| | - Amsal Tarekegne
- Zambia Seed Company Limited (Zamseed), Lusaka P.O. Box 35441, Zambia
| | - Maryke T. Labuschagne
- Department of Plant Sciences, University of the Free State, Bloemfontein 9301, South Africa;
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Yang Q, Zhao D, Zhang C, Sreenivasulu N, Sun SSM, Liu Q. Lysine biofortification of crops to promote sustained human health in the 21st century. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:1258-1267. [PMID: 34723338 DOI: 10.1093/jxb/erab482] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 10/31/2021] [Indexed: 06/13/2023]
Abstract
Crop biofortification is pivotal in preventing malnutrition, with lysine considered the main limiting essential amino acid (EAA) required to maintain human health. Lysine deficiency is predominant in developing countries where cereal crops are the staple food, highlighting the need for efforts aimed at enriching the staple diet through lysine biofortification. Successful modification of aspartate kinase (AK) and dihydrodipicolinate synthase (DHDPS) feedback inhibition has been used to enrich lysine in transgenic rice plants without yield penalty, while increases in the lysine content of quality protein maize have been achieved via marker-assisted selection. Here, we reviewed the lysine metabolic pathway and proposed the use of metabolic engineering targets as the preferred option for fortification of lysine in crops. Use of gene editing technologies to translate the findings and engineer lysine catabolism is thus a pioneering step forward.
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Affiliation(s)
- Qingqing Yang
- Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Jiangsu Key Laboratory of Crop Genetics and Physiology, College of Agriculture, Yangzhou University, Yangzhou, China
- State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Dongsheng Zhao
- Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Jiangsu Key Laboratory of Crop Genetics and Physiology, College of Agriculture, Yangzhou University, Yangzhou, China
| | - Chuangquan Zhang
- Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Jiangsu Key Laboratory of Crop Genetics and Physiology, College of Agriculture, Yangzhou University, Yangzhou, China
| | - Nese Sreenivasulu
- Consumer Driven Grain Quality and Nutrition Unit, Rice Breeding Innovation Platform, International Rice Research Institute, Los Banos, Philippines
| | - Samuel Sai-Ming Sun
- State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Qiaoquan Liu
- Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Jiangsu Key Laboratory of Crop Genetics and Physiology, College of Agriculture, Yangzhou University, Yangzhou, China
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Combining higher accumulation of amylopectin, lysine and tryptophan in maize hybrids through genomics-assisted stacking of waxy1 and opaque2 genes. Sci Rep 2022; 12:706. [PMID: 35027624 PMCID: PMC8758761 DOI: 10.1038/s41598-021-04698-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 12/22/2021] [Indexed: 11/15/2022] Open
Abstract
Waxy maize rich in amylopectin has emerged as a preferred food. However, waxy maize is poor in lysine and tryptophan, deficiency of which cause severe health problems. So far, no waxy hybrid with high lysine and tryptophan has been developed and commercialized. Here, we combined recessive waxy1 (wx1) and opaque2 (o2) genes in the parental lines of four popular hybrids (HQPM1, HQPM4, HQPM5, and HQPM7) using genomics-assisted breeding. The gene-based markers, wx-2507F/RG and phi057 specific for wx1 and o2, respectively were successfully used to genotype BC1F1, BC2F1 and BC2F2 populations. Background selection with > 100 SSRs resulted in recovering > 94% of the recurrent parent genome. The reconstituted hybrids showed 1.4-fold increase in amylopectin (mean: 98.84%) compared to the original hybrids (mean: 72.45%). The reconstituted hybrids also showed 14.3% and 14.6% increase in lysine (mean: 0.384%) and tryptophan (mean: 0.102%), respectively over the original hybrids (lysine: 0.336%, tryptophan: 0.089%). Reconstituted hybrids also possessed similar grain yield (mean: 6248 kg/ha) with their original versions (mean: 6111 kg/ha). The waxy hybrids with high lysine and tryptophan assume great significance in alleviating malnutrition through sustainable and cost-effective means. This is the first report of development of lysine and tryptophan rich waxy hybrids using genomics-assisted selection.
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Mehta BK, Chhabra R, Muthusamy V, Zunjare RU, Baveja A, Chauhan HS, Prakash NR, Chalam VC, Singh AK, Hossain F. Expression analysis of β-carotene hydroxylase1 and opaque2 genes governing accumulation of provitamin-A, lysine and tryptophan during kernel development in biofortified sweet corn. 3 Biotech 2021; 11:325. [PMID: 34194909 DOI: 10.1007/s13205-021-02837-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 05/07/2021] [Indexed: 12/01/2022] Open
Abstract
Traditional sweet corn possesses low levels of provitamin-A (proA), lysine and tryptophan. Mutant version of β-carotene hydroxylase1 (crtRB1) gene affecting the accumulation of β-carotene (BC), β-cryptoxanthin (BCX) and proA, and opaque2 (o2) gene governing the enhancement of lysine and tryptophan were introgressed together into elite sweet corn inbreds through marker-assisted selection. Here, we analyzed the expression pattern of crtRB1 and o2 genes among introgressed and traditional sweet corn inbreds at 20-, 24- and 28-days after pollination (DAP). The introgressed inbreds possessed two- to sevenfolds higher BC, BCX, proA, lysine and tryptophan compared to their original inbreds. However, all the nutrients attained the peak at 20-DAP (BC: 9.95 µg/g, BCX: 8.21 µg/g, proA: 14.05 µg/g, lysine: 0.301%, tryptophan: 0.074%), which gradually reduced through 24-DAP (BC: 8.24 µg/g, BCX: 7.53 µg/g, proA: 12.01 µg/g, lysine: 0.273%, tryptophan: 0.057%) and 28-DAP (BC: 5.84 µg/g, BCX: 5.82 µg/g, proA: 8.75 µg/g, lysine: 0.202%, tryptophan: 0.037%). Biofortified sweet corn inbreds possessed significantly lower expression levels of crtRB1 (4.1-fold) and o2 (2.2-fold) compared to their wild type alleles in traditional sweet corn inbreds across DAPs. The expression of crtRB1 and o2 increased from 20-DAP to attain the highest peak at 24-DAP, and further decreased by 28-DAP. The transcript levels of crtRB1 were negatively correlated with BC (r = - 0.83), BCX (r = - 0.79) and proA (r = - 0.83) across dates of harvest. Lysine (r = - 0.83) and tryptophan (r = - 0.73) were also inversely associated with o2 transcript levels. This is the first report on expression of crtRB1 and o2 genes during kernel development in biofortified sweet corn. This information holds immense promise in understanding the dynamics of gene-regulation during kernel development in sweet corn.
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Affiliation(s)
- Brijesh Kumar Mehta
- ICAR-Indian Agricultural Research Institute, New Delhi, 110012 India
- Present Address: ICAR-Indian Grassland and Fodder Research Institute, Jhansi, 284003 India
| | - Rashmi Chhabra
- ICAR-Indian Agricultural Research Institute, New Delhi, 110012 India
| | - Vignesh Muthusamy
- ICAR-Indian Agricultural Research Institute, New Delhi, 110012 India
| | | | - Aanchal Baveja
- ICAR-Indian Agricultural Research Institute, New Delhi, 110012 India
| | | | | | | | - Ashok Kumar Singh
- ICAR-Indian Agricultural Research Institute, New Delhi, 110012 India
| | - Firoz Hossain
- ICAR-Indian Agricultural Research Institute, New Delhi, 110012 India
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Garg M, Sharma A, Vats S, Tiwari V, Kumari A, Mishra V, Krishania M. Vitamins in Cereals: A Critical Review of Content, Health Effects, Processing Losses, Bioaccessibility, Fortification, and Biofortification Strategies for Their Improvement. Front Nutr 2021; 8:586815. [PMID: 34222296 PMCID: PMC8241910 DOI: 10.3389/fnut.2021.586815] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 04/28/2021] [Indexed: 12/19/2022] Open
Abstract
Around the world, cereals are stapled foods and good sources of vitamins A, B, and E. As cereals are inexpensive and consumed in large quantities, attempts are being made to enrich cereals using fortification and biofortification in order to address vitamin deficiency disorders in a vulnerable population. The processing and cooking of cereals significantly affect vitamin content. Depending on grain structure, milling can substantially reduce vitamin content, while cooking methods can significantly impact vitamin retention and bioaccessibility. Pressure cooking has been reported to result in large vitamin losses, whereas minimal vitamin loss was observed following boiling. The fortification of cereal flour with vitamins B1, B2, B3, and B9, which are commonly deficient, has been recommended; and in addition, region-specific fortification using either synthetic or biological vitamins has been suggested. Biofortification is a relatively new concept and has been explored as a method to generate vitamin-rich crops. Once developed, biofortified crops can be utilized for several years. A recent cereal biofortification success story is the enrichment of maize with provitamin A carotenoids.
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Affiliation(s)
- Monika Garg
- Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
| | - Anjali Sharma
- Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
| | - Shreya Vats
- Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
| | - Vandita Tiwari
- Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
| | - Anita Kumari
- Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), Mohali, India
| | - Vibhu Mishra
- Food Engineering and Nutrition, Center of Innovative and Applied Bioprocessing, Mohali, India
| | - Meena Krishania
- Food Engineering and Nutrition, Center of Innovative and Applied Bioprocessing, Mohali, India
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Mehta BK, Muthusamy V, Baveja A, Chauhan HS, Chhabra R, Bhatt V, Chand G, Zunjare RU, Singh AK, Hossain F. Composition analysis of lysine, tryptophan and provitamin-A during different stages of kernel development in biofortified sweet corn. J Food Compost Anal 2020. [DOI: 10.1016/j.jfca.2020.103625] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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22
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Mehta BK, Muthusamy V, Zunjare RU, Baveja A, Chauhan HS, Chhabra R, Singh AK, Hossain F. Biofortification of sweet corn hybrids for provitamin-A, lysine and tryptophan using molecular breeding. J Cereal Sci 2020. [DOI: 10.1016/j.jcs.2020.103093] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Pukalenthy B, Manickam D, Adhimoolam K, Mahesh SG, Ramanathan N, Chandran S, Sampathrajan V, Rajasekaran R, Arunachalam K, Senthil K, Muthusamy V, Hossain F, Natesan S. Marker aided introgression of opaque 2 (o2) allele improving lysine and tryptophan in maize ( Zea mays L.). PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2020; 26:1925-1930. [PMID: 32943826 PMCID: PMC7468007 DOI: 10.1007/s12298-020-00857-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 06/14/2020] [Accepted: 07/30/2020] [Indexed: 06/11/2023]
Abstract
Maize is the predominant food source for the world population, but lack of lysine and tryptophan in maize endosperm cannot fulfill the nutritional requirements of humans. Hence, the improvement of lysine and tryptophan content is the ultimate goal of maize biofortification programs. In the present study, the marker-assisted backcross (MABC) breeding strategy was used to enhance the lysine and tryptophan content of the elite maize inbred line UMI1230 by introgressing opaque 2 (o2) gene from the VQL1. During the transfer of the gene into UMI1230, SSR marker umc1066 tightly associated with o2 used for foreground selection. Background recovery was estimated using 168 SSR markers. Phenotype screening for morphological traits was adopted to choose plants parallel to UMI1230. As a result, four BC2F3 improved lines (DBT5-1-14/25-5/25-8/25-8/25, DBT5-1-14/25-5/25-8/25-7/25, DBT5-1-14/25-5/25-8/25-10/25 and DBT5-1-14/25-5/25-8/25-12/25) with o2 were developed. The improved line's background genome recovery varied between 90.60 and 94.80%. Also, the improved lines had better agronomic performance along with increased lysine (0.311-0.331%) and tryptophan (0.040-0.048%) contents. In summary, the MABC breeding strategy has successfully improved the levels of lysine and tryptophan in UMI1230 without affecting agronomic performance. The improved line's hold great potential as donors in biofortification programs in maize.
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Affiliation(s)
- Bharathi Pukalenthy
- Department of Plant Breeding and Genetics, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, Tamil Nadu India
| | - Dhasarathan Manickam
- Department of Biotechnology, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, Tamil Nadu India
| | - Karthikeyan Adhimoolam
- Department of Biotechnology, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, Tamil Nadu India
| | - Sandesh Goragundi Mahesh
- Department of Plant Breeding and Genetics, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, Tamil Nadu India
| | - Nagalakshmi Ramanathan
- Centre for Plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu India
| | - Sarankumar Chandran
- Department of Plant Molecular Biology and Bioinformatics, Centre for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu India
| | - Vellaikumar Sampathrajan
- Department of Biotechnology, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, Tamil Nadu India
| | - Ravikesavan Rajasekaran
- Department of Millets, Centre for Plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu India
| | - Kavithapushpam Arunachalam
- Department of Soil Science and Agricultural Chemistry, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Killikulam, Tamil Nadu India
| | - Kalaiselvi Senthil
- Department of Biochemistry, Biotechnology and Bioinformatics, Avinashilingam Institute for Home Science and Higher Education for Women, Coimbatore, Tamil Nadu India
| | - Vignesh Muthusamy
- Division of Genetics, Indian Agricultural Research Institute, New Delhi, India
| | - Firoz Hossain
- Division of Genetics, Indian Agricultural Research Institute, New Delhi, India
| | - Senthil Natesan
- Department of Plant Molecular Biology and Bioinformatics, Centre for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu India
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Development and validation of breeder-friendly gene-based markers for lpa1-1 and lpa2-1 genes conferring low phytic acid in maize kernel. 3 Biotech 2020; 10:121. [PMID: 32123645 DOI: 10.1007/s13205-020-2113-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 02/02/2020] [Indexed: 10/25/2022] Open
Abstract
Based on C (wild) to T (mutant) transition at amino acid position 1432 bp of lpa1-1 gene, two dominant markers each specific to wild type (LPA1) and mutant (lpa1-1) allele were developed and validated across seven F2 populations. Joint segregation of these markers behaved in co-dominant fashion, clearly distinguishing heterozygote from two other homozygote genotypes. Full length sequence alignment between wild type (LPA2) and mutant (lpa2-1) allele revealed one transition mutation (A to G) and a co-dominant CAPS marker was developed which differentiated all three types of segregants across seven F2 populations. Across populations, segregants with lpa1-1/lpa1-1 (1.77 mg/g) and lpa2-1/lpa2-1 (1.85 mg/g) possessed significantly lower phytic acid compared to LPA1/LPA1 (2.58 mg/g) and LPA2/LPA2 (2.53 mg/g). Inorganic phosphorus was however higher in recessive homozygotes (lpa1-1/lpa1-1: 0.77 mg/g, lpa2-1/lpa2-1: 0.53 mg/g) than the dominant homozygotes (LPA1/LPA1: 0.33 mg/g, LPA2/LPA2: 0.19 mg/g). Overall, homozygous segregants of lpa1-1 and lpa2-1 showed 31% and 27% reduction of phytic acid, respectively. Analysis of phytate and inorganic phosphorous in the maize kernel in these segregating populations confirmed co-segregation of trait and markers specific to lpa1-1 and lpa2-1. This is the first report of the development of breeder-friendly gene-based markers for lpa1-1 and lpa2-1; and it holds great significance for maize biofortification.
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Prasanna BM, Palacios-Rojas N, Hossain F, Muthusamy V, Menkir A, Dhliwayo T, Ndhlela T, San Vicente F, Nair SK, Vivek BS, Zhang X, Olsen M, Fan X. Molecular Breeding for Nutritionally Enriched Maize: Status and Prospects. Front Genet 2020; 10:1392. [PMID: 32153628 PMCID: PMC7046684 DOI: 10.3389/fgene.2019.01392] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 12/19/2019] [Indexed: 12/13/2022] Open
Abstract
Maize is a major source of food security and economic development in sub-Saharan Africa (SSA), Latin America, and the Caribbean, and is among the top three cereal crops in Asia. Yet, maize is deficient in certain essential amino acids, vitamins, and minerals. Biofortified maize cultivars enriched with essential minerals and vitamins could be particularly impactful in rural areas with limited access to diversified diet, dietary supplements, and fortified foods. Significant progress has been made in developing, testing, and deploying maize cultivars biofortified with quality protein maize (QPM), provitamin A, and kernel zinc. In this review, we outline the status and prospects of developing nutritionally enriched maize by successfully harnessing conventional and molecular marker-assisted breeding, highlighting the need for intensification of efforts to create greater impacts on malnutrition in maize-consuming populations, especially in the low- and middle-income countries. Molecular marker-assisted selection methods are particularly useful for improving nutritional traits since conventional breeding methods are relatively constrained by the cost and throughput of nutritional trait phenotyping.
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Affiliation(s)
| | | | - Firoz Hossain
- ICAR-Indian Agricultural Research Institute (IARI), New Delhi, India
| | - Vignesh Muthusamy
- ICAR-Indian Agricultural Research Institute (IARI), New Delhi, India
| | - Abebe Menkir
- International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria
| | | | | | | | | | | | | | - Mike Olsen
- International Maize and Wheat Improvement Center (CIMMYT), Nairobi, Kenya
| | - Xingming Fan
- Institute of Crop Sciences, Yunnan Academy of Agricultural Sciences (YAAS), Kunming, China
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Chandran S, Pukalenthy B, Adhimoolam K, Manickam D, Sampathrajan V, Chocklingam V, Eswaran K, Arunachalam K, Joikumar Meetei L, Rajasekaran R, Muthusamy V, Hossain F, Natesan S. Marker-Assisted Selection to Pyramid the Opaque-2 (O2) and β-Carotene (crtRB1) Genes in Maize. Front Genet 2019; 10:859. [PMID: 31611905 PMCID: PMC6775488 DOI: 10.3389/fgene.2019.00859] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Accepted: 08/16/2019] [Indexed: 11/13/2022] Open
Abstract
Maize is an excellent nutritional source and is consumed as a staple food in different parts of the world, including India. Developing a maize genotype with a combination of higher lysine and tryptophan, along with β-carotene, can help alleviate the problem of protein-energy malnutrition (PEM) and vitamin A deficiency (VAD). This study is aimed at improving lysine and tryptophan content by transferring opaque-2 (o2) gene from donor HKI163 to β-carotene-rich inbred lines viz., UMI1200β+ and UMI1230β+. For this purpose, F1, BC1F1, BC2F1, BC2F2, and BC2F3 plants were developed using an o2 line HKI163 and two β-carotene-rich inbred lines, UMI1200β+ and UMI1230β+, as the parents. Foreground selection using the associated marker umc1066 for the o2 gene and the marker crtRB1 3'TE for the crtRB1 gene was used to select the target genes. A total of 236 simple sequence repeat (SSR) markers distributed evenly across the maize genome were employed for the background selection. To fix the crtRB1 allele in the BC1F1 stage, individual plants homozygous at the crtRB1 locus and heterozygous at the o2 locus were selected and used for backcrossing to produce BC2F1 plants. Furthermore, the selected heterozygous BC2F1 plants from both crosses were selfed to obtain the BC2F2 plants, which were then selected for the target gene and selfed to generate the BC2F3 lines. From each cross, five improved lines with homozygous marker alleles for the crtRB1 and o2 genes with a recurrent parent genome (RPG) recovery ranging from 86.75 to 91.21% in UMI1200β+×HKI163 and 80.00 to 90.08% in UMI1230β+×HKI163 were identified. The improved lines had good agronomic performance and possessed high lysine (0.294-0.332%), tryptophan (0.073-0.081%), and β-carotene (6.12-7.38 µg/g) content. These improved lines can be used as genetic resources for maize improvement.
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Affiliation(s)
- Sarankumar Chandran
- Department of Plant Breeding and Genetics, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India
| | - Bharathi Pukalenthy
- Department of Plant Breeding and Genetics, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India
| | - Karthikeyan Adhimoolam
- Department of Biotechnology, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India
| | - Dhasarathan Manickam
- Department of Biotechnology, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India
| | - Vellaikumar Sampathrajan
- Department of Biotechnology, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India
| | - Vanniarajan Chocklingam
- Department of Plant Breeding and Genetics, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India
| | - Kokiladevi Eswaran
- Department of Plant Biotechnology, Center for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, India
| | - Kavithapushpam Arunachalam
- Department of Soil Science and Agricultural Chemistry, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Killikulam, India
| | - Laishram Joikumar Meetei
- Department of Tree Improvement and Plant Breeding and Genetics, Central Agricultural University, Imphal, India
| | - Ravikesavan Rajasekaran
- Department of Millet, Center for Plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore, India
| | - Vignesh Muthusamy
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Firoz Hossain
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Senthil Natesan
- Department of Plant Molecular Biology and Bioinformatics, Center for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, India
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Wang W, Niu S, Dai Y, Wang M, Li Y, Yang W, Zhao D. The Zea mays mutants opaque2 and opaque16 disclose lysine change in waxy maize as revealed by RNA-Seq. Sci Rep 2019; 9:12265. [PMID: 31439855 PMCID: PMC6706447 DOI: 10.1038/s41598-019-48478-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 07/31/2019] [Indexed: 12/14/2022] Open
Abstract
In maize, opaque2 (o2) and opaque16 (o16) alleles can increase lysine content, while the waxy (wx) gene can enhance the amylopectin content of grains. In our study, o2 and o16 alleles were backcrossed into waxy maize line (wxwx). The o2o2o16o16wxwx lines had amylopectin contents similar to those of waxy line. Their nutritional value was better than waxy line, but the mechanism by which the o2 and o16 alleles increased the lysine content of waxy maize remained unclear. The o2o2o16o16wxwx lines and their parents on kernels (18th day after pollination) were subjected to RNA sequencing (RNA-Seq). The RNA-Seq analysis revealed 272 differentially expressed genes (DEGs). Functional analyses revealed that these DEGs were mainly related to biomass metabolism. Among them, in o2o2o16o16wxwx lines, 15 genes encoding α-zein were down-regulated, which resulted in the reduction of α-zein synthesis and increased lysine content; lkr/sdh1 and Zm00001d020984.1 genes involved in the lysine degradation pathway were down-regulated, thereby inhibited lysine degradation; sh2, bt2 and ae1 genes involved in starch metabolism were upregulated, leaded to wrinkling kernel and farinaceous endosperm. Our transcriptional-level identification of key genes responsible for increased grain lysine content and farinaceous endosperm formation following introgression of o2 and o16 alleles should promote molecular breeding for maize quality.
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Affiliation(s)
- Wei Wang
- The State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), Guizhou University, Guiyang, 550025, China.,Guizhou Institute of Upland Food Crops, Guiyang Station for DUS Testing Center of New Plant Varieties (MOA), Guizhou Academy of Agricultural Sciences, Guiyang, 550006, China
| | - Suzhen Niu
- The State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), Guizhou University, Guiyang, 550025, China
| | - Yi Dai
- The State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), Guizhou University, Guiyang, 550025, China
| | - Mingchun Wang
- Guizhou Institute of Upland Food Crops, Guiyang Station for DUS Testing Center of New Plant Varieties (MOA), Guizhou Academy of Agricultural Sciences, Guiyang, 550006, China
| | - Yan Li
- The State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), Guizhou University, Guiyang, 550025, China
| | - Wenpeng Yang
- Guizhou Institute of Upland Food Crops, Guiyang Station for DUS Testing Center of New Plant Varieties (MOA), Guizhou Academy of Agricultural Sciences, Guiyang, 550006, China.
| | - Degang Zhao
- The State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), Guizhou University, Guiyang, 550025, China. .,Guizhou Institute of Upland Food Crops, Guiyang Station for DUS Testing Center of New Plant Varieties (MOA), Guizhou Academy of Agricultural Sciences, Guiyang, 550006, China.
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Wang W, Dai Y, Wang M, Yang W, Zhao D. Transcriptome Dynamics of Double Recessive Mutant, o2o2o16o16, Reveals the Transcriptional Mechanisms in the Increase of Its Lysine and Tryptophan Content in Maize. Genes (Basel) 2019; 10:genes10040316. [PMID: 31018625 PMCID: PMC6523931 DOI: 10.3390/genes10040316] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 04/12/2019] [Accepted: 04/16/2019] [Indexed: 11/16/2022] Open
Abstract
In maize, pyramiding of o2 and o16 alleles can greatly improve the nutritional quality of grains. To dissect its molecular mechanism, we created a double recessive mutant line, o2o2o16o16, by introgression of the o2 and o16 alleles into the wild-type maize inbred line, by molecular marker-assisted backcross selection. The kernels (18 day after pollination (DAP), 28 DAP, and 38 DAP) of the o2o2o16o16 mutant and its parent lines were subject to RNA sequencing (RNA-Seq). The RNA-Seq analysis revealed that 59 differentially expressed genes (DEGs) were involved in lysine metabolism and 43 DEGs were involved in tryptophan metabolism. Among them, the genes encoding AK, ASADH, and Dap-F in the lysine synthesis pathway were upregulated at different stages of endosperm development, promoting the synthesis of lysine. Meanwhile, the genes encoding LKR/SDH and L-PO in the lysine degradation pathway were downregulated, inhibiting the degradation of lysine. Moreover, the genes encoding TAA and YUC in the tryptophan metabolic pathway were downregulated, restraining the degradation of tryptophan. Thus, pyramiding o2 and o16 alleles could increase the lysine and tryptophan content in maize. These above results would help to uncover the molecular mechanisms involved in the increase in lysine and the tryptophan content, through the introgression of o2 and o16 alleles into the wild-type maize.
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Affiliation(s)
- Wei Wang
- The State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), Guizhou University, Guiyang 550025, China.
- Guizhou Institute of Upland Food Crops, Guiyang Station for DUS Testing Center of New Plant Varieties (MOA), Guizhou Academy of Agricultural Sciences, Guiyang 550006, China.
| | - Yi Dai
- The State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), Guizhou University, Guiyang 550025, China.
| | - Mingchun Wang
- Guizhou Institute of Upland Food Crops, Guiyang Station for DUS Testing Center of New Plant Varieties (MOA), Guizhou Academy of Agricultural Sciences, Guiyang 550006, China.
| | - Wenpeng Yang
- Guizhou Institute of Upland Food Crops, Guiyang Station for DUS Testing Center of New Plant Varieties (MOA), Guizhou Academy of Agricultural Sciences, Guiyang 550006, China.
| | - Degang Zhao
- The State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), Guizhou University, Guiyang 550025, China.
- Guizhou Institute of Upland Food Crops, Guiyang Station for DUS Testing Center of New Plant Varieties (MOA), Guizhou Academy of Agricultural Sciences, Guiyang 550006, China.
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Das AK, Muthusamy V, Zunjare RU, Chauhan HS, Sharma PK, Bhat JS, Guleria SK, Saha S, Hossain F. Genetic variability-, genotype × environment interactions- and combining ability-analyses of kernel tocopherols among maize genotypes possessing novel allele of γ-tocopherol methyl transferase (ZmVTE4). J Cereal Sci 2019. [DOI: 10.1016/j.jcs.2018.12.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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30
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Molecular analysis of mutant granule-bound starch synthase-I ( waxy1) gene in diverse waxy maize inbreds. 3 Biotech 2019; 9:3. [PMID: 30555769 DOI: 10.1007/s13205-018-1530-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 12/05/2018] [Indexed: 12/20/2022] Open
Abstract
Waxy corn is popular beacuse of its high amylopectin due to mutation in granule-bound starch synthase-I or Waxy1 (Wx1) gene. Here, we characterized the wx1 allele among 24 diverse waxy inbreds using gene-based markers. A total of 29 alleles with average of 1.81 alleles/locus were observed. Major allele frequency varied from 0.42 to 1.00, with mean of 0.74. The polymorphism information content ranged from 0.00 to 0.56 (average 0.24). Three simple sequence repeat markers, viz., phi027, phi022 and phi061 were more polymorphic in the study. The mean heterozygosity was 0.04, which indicated attainment of higher levels of homozygosity. Dissimilarity coefficient varied from 0.00 to 0.90 with average of 0.51. Seventeen diverse haplotypes of wx1 allele were observed that was consistent with the pedigree. Cluster analyses grouped 24 genotypes into two main clusters each having sub-clusters. The information generated here possesses great potential for improvement of high amylopectin in maize through marker-assisted selection. This is the first report of molecular dissection of wx1 gene among the novel waxy inbreds developed in India.
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