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Wang M, Jiang N, Xu Y, Chen X, Wang C, Wang C, Wang S, Xu K, Chai S, Yu Q, Zhang Z, Zhang H. CmBr confers fruit bitterness under CPPU treatment in melon. PLANT BIOTECHNOLOGY JOURNAL 2024. [PMID: 38816932 DOI: 10.1111/pbi.14399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 04/06/2024] [Accepted: 05/13/2024] [Indexed: 06/01/2024]
Abstract
Many biotic or abiotic factors such as CPPU (N-(2-chloro-pyridin-4-yl)-N'-phenylurea), a growth regulator of numerous crops, can induce bitterness in cucurbits. In melon, cucurbitacin B is the major compound leading to bitterness. However, the molecular mechanism underlying CuB biosynthesis in response to different conditions remains unclear. Here, we identified a set of genes involved in CPPU-induced CuB biosynthesis in melon fruit and proposed CmBr gene as the major regulator. Using CRISPR/Cas9 gene editing, we confirmed CmBr's role in regulating CuB biosynthesis under CPPU treatment. We further discovered a CPPU-induced MYB-related transcription factor, CmRSM1, which specifically binds to the Myb motif within the CmBr promoter and activates its expression. Moreover, we developed an introgression line by introducing the mutated Cmbr gene into an elite variety and eliminated CPPU-induced bitterness, demonstrating its potential application in breeding. This study offers a valuable tool for breeding high-quality non-bitter melon varieties and provides new insights into the regulation of secondary metabolites under environmental stresses.
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Affiliation(s)
- Mingyan Wang
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Laboratory of Quality & Safety Risk Assessment for Fruit (Qingdao), Ministry of Agriculture and Rural Affairs, National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products (Qingdao), College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Naiyu Jiang
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Laboratory of Quality & Safety Risk Assessment for Fruit (Qingdao), Ministry of Agriculture and Rural Affairs, National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products (Qingdao), College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Yuanchao Xu
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Shenzhen Key Laboratory of Agricultural Synthetic Biology, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Xinxiu Chen
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Laboratory of Quality & Safety Risk Assessment for Fruit (Qingdao), Ministry of Agriculture and Rural Affairs, National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products (Qingdao), College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Cui Wang
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Laboratory of Quality & Safety Risk Assessment for Fruit (Qingdao), Ministry of Agriculture and Rural Affairs, National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products (Qingdao), College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Chuangjiang Wang
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Laboratory of Quality & Safety Risk Assessment for Fruit (Qingdao), Ministry of Agriculture and Rural Affairs, National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products (Qingdao), College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Shiqi Wang
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Laboratory of Quality & Safety Risk Assessment for Fruit (Qingdao), Ministry of Agriculture and Rural Affairs, National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products (Qingdao), College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Kuipeng Xu
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Laboratory of Quality & Safety Risk Assessment for Fruit (Qingdao), Ministry of Agriculture and Rural Affairs, National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products (Qingdao), College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Sen Chai
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Laboratory of Quality & Safety Risk Assessment for Fruit (Qingdao), Ministry of Agriculture and Rural Affairs, National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products (Qingdao), College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Qing Yu
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Laboratory of Quality & Safety Risk Assessment for Fruit (Qingdao), Ministry of Agriculture and Rural Affairs, National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products (Qingdao), College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Zhonghua Zhang
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Laboratory of Quality & Safety Risk Assessment for Fruit (Qingdao), Ministry of Agriculture and Rural Affairs, National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products (Qingdao), College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Huimin Zhang
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Laboratory of Quality & Safety Risk Assessment for Fruit (Qingdao), Ministry of Agriculture and Rural Affairs, National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products (Qingdao), College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
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Debnath P, Das B, Singha S, Kar A, Haldar PK, Sharma N, Mukherjee PK. Quantification of cucurbitacin E in different varieties of melon ( Cucumis melo L.) fruit through validated RP-HPLC method. Nat Prod Res 2024; 38:1273-1279. [PMID: 36278903 DOI: 10.1080/14786419.2022.2136656] [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: 09/22/2021] [Revised: 09/28/2022] [Accepted: 10/07/2022] [Indexed: 10/31/2022]
Abstract
The different varieties of melons (Cucumis melo L.) have been used in various traditional systems of medicine for decades to treat different ailments, including inflammation, cancer, cardiovascular, diabetes, edema, etc. The present study was designed for the quantification of cucurbitacin E in five different varieties of melon fruit through a validated RP-HPLC method. A solvent system is being optimized with a 70:30 (v/v) ratio of acetonitrile: water (1% glacial acetic acid) at a 1 mL/min flow rate and scanning spectrum (λmax) of 230 nm. A calibration curve for standard cucurbitacin E was generated and found to be linear (1-100 µg/mL). The variation of cucurbitacin E content among five different varieties of melon fruits is 0.0129% w/w- 0.231% w/w. This precise and reproducible method may be beneficial in addressing the quality-related aspects of medicinal food plants of Cucurbitaceae and its derived products or formulations.
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Affiliation(s)
- Pradip Debnath
- Department of Pharmaceutical Technology, School of Natural Product Studies, Jadavpur University, Kolkata, India
- Department of Pharmacy, Comilla University, Shalmanpur, Bangladesh
| | - Bhaskar Das
- Department of Pharmaceutical Technology, School of Natural Product Studies, Jadavpur University, Kolkata, India
| | - Seha Singha
- Department of Pharmaceutical Technology, School of Natural Product Studies, Jadavpur University, Kolkata, India
| | - Amit Kar
- Institute of Bioresources and Sustainable Development (An autonomous Institute under Department of Biotechnology), Ministry of Science & Technology, Govt. of India), Imphal, India
| | - Pallab Kanti Haldar
- Department of Pharmaceutical Technology, School of Natural Product Studies, Jadavpur University, Kolkata, India
| | - Nanaocha Sharma
- Institute of Bioresources and Sustainable Development (An autonomous Institute under Department of Biotechnology), Ministry of Science & Technology, Govt. of India), Imphal, India
| | - Pulok K Mukherjee
- Department of Pharmaceutical Technology, School of Natural Product Studies, Jadavpur University, Kolkata, India
- Institute of Bioresources and Sustainable Development (An autonomous Institute under Department of Biotechnology), Ministry of Science & Technology, Govt. of India), Imphal, India
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Lee NR, Kim YX, Lee Y, Lee C, Song Y, Park H, Lee CH, Lee Y. Metabolomics Reveals the Effects of Nitrogen/Phosphorus/Potassium (NPK) Fertilizer Levels on Cucumber Fruit Raised in Different Nutrient Soils. Metabolites 2024; 14:102. [PMID: 38392994 PMCID: PMC10891504 DOI: 10.3390/metabo14020102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/15/2024] [Accepted: 01/28/2024] [Indexed: 02/25/2024] Open
Abstract
Fertilizers are widely used to improve the quality of fruits and vegetables. However, the overuse of fertilizers has become an issue because it causes environmental problems and negatively affects productivity and fruit quality. In this study, we examined the effects of nitrogen, phosphorus, and potassium (NPK) fertilizer levels on the metabolism of cucumber fruit in low- and high-nutrient soils using mass-spectrometry-based metabolomics approaches. Cucumber metabolite content was notably different depending on the initial soil nutrient status. Most amino acids and phenylpropanoids were abundant in the cucumbers raised in low-nutrient soil, whereas organic acids, some amino acids (aspartate, glutamate, and ornithine), and carbohydrates were comparatively higher in fruits from high-nutrient soil. The fertilizer supply resulted in an alteration in the metabolite profile, while no change in fruit yield was observed in either low- or high-nutrient soils. Fertilizer treatment perturbed the metabolite contents in cucumbers from low-nutrient soil. In contrast, treatment with higher concentrations of fertilizer in high-nutrient soil increased phenylpropanoid content in the cucumbers, while most metabolites decreased. In conclusion, fertilization levels should be carefully determined, considering culture conditions such as the original soil status, to increase product yield and fruit quality and avoid environmental problems.
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Affiliation(s)
- Na-Rae Lee
- Research Institute for Bioactive-Metabolome Network, Konkuk University, Seoul 05029, Republic of Korea;
| | - Yangmin X. Kim
- Soil and Fertilizer Division, National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Republic of Korea; (Y.X.K.); (C.L.); (Y.S.); (H.P.)
- Highland Agriculture Research Institute, National Institute of Crop Science, Rural Development Administration, Pyeongchang 25342, Republic of Korea
| | - Yerim Lee
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea;
| | - Chanwook Lee
- Soil and Fertilizer Division, National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Republic of Korea; (Y.X.K.); (C.L.); (Y.S.); (H.P.)
| | - Yosung Song
- Soil and Fertilizer Division, National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Republic of Korea; (Y.X.K.); (C.L.); (Y.S.); (H.P.)
| | - Hyejin Park
- Soil and Fertilizer Division, National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Republic of Korea; (Y.X.K.); (C.L.); (Y.S.); (H.P.)
| | - Choong Hwan Lee
- Research Institute for Bioactive-Metabolome Network, Konkuk University, Seoul 05029, Republic of Korea;
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea;
| | - Yejin Lee
- Soil and Fertilizer Division, National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Republic of Korea; (Y.X.K.); (C.L.); (Y.S.); (H.P.)
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Guo K, Zhao J, Fang S, Zhang Q, Nie L, Zhao W. The effects of different rootstocks on aroma components, activities and genes expression of aroma-related enzymes in oriental melon fruit. PeerJ 2024; 12:e16704. [PMID: 38192601 PMCID: PMC10773451 DOI: 10.7717/peerj.16704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 11/30/2023] [Indexed: 01/10/2024] Open
Abstract
Grafting is widely applied in the cultivation of melon. In this study, 'Qinmi No.1' (Cucumis melo L.(QG)) and 'Ribenxuesong' (Cucurbita maxima Duch. (RG)) were used as rootstocks for 'Qingxin Yangjiaocui' (Cucumis melo L.). The results showed that grafting with muskmelon rootstocks had no significant effect on fruit aroma, but grafting with pumpkin rootstocks significantly reduced the odor intensity and odor preference scores of melon fruits. Compared with the fruits from self-grafted plants (SG), four new aromatic volatiles with a sweet smell were detected, the alcohol dehydrogenase (ADH) activity was significantly decreased at 30 DAP, but unaffected at 42 DAP in QG fruits. There was no difference for alcohol acetyltransferase (AAT) activity between QG and SG fruits. The expression level of CmADH2 was significantly higher at 30 DAP and 42 DAP, but CmAAT2 was significantly lower at 42 DAP in QG fruits compared with SG fruits. In RG fruits, the main aroma compounds including butanoic acid ethyl ester, 2-methyl-2-butene-1-al, and 2-methylheptan-1-al were absent, while the volatile compounds with unpleasant odor characteristics including trans, cis-2,6-nonadien-1-ol, (E,E)-2,4-heptadienal, octanoic acid, and styrene were detected. Compared with SG fruits, 1-nonanol and 1-heptanol with green odor characteristics were significantly increased, but eucalyptol and farnesene with fruity aroma characteristics were significantly decreased in RG fruits. The ADH activity of RG fruits was significantly lower than that of SG fruits at 30 DAP and the AAT activity was significantly lower than that of SG fruits at 42 DAP. In addition, the expression levels of CmADH and CmAAT homologs in RG fruits were significantly lower than those in SG or QG fruits. These results show that grafting with pumpkin rootstocks affected the main aroma components, reduced ADH and AAT activities, and down-regulated the expression levels of CmADHs and CmAATs in the melon fruits. This study reveals the mechanism of different rootstocks on melon fruit aroma quality, and lays a theoretical foundation for the selection of rootstocks in melon production. Future studies using overexpression or CRISPR/CAS system to obtain stable transgenic lines of genes encoding key aromatic volatiles, would be promising to effectively improve the flavor quality of melon.
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Affiliation(s)
- Kedong Guo
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei, China
- Hebei Key Laboratory of Vegetable Germplasm Innovation and Utilization, BaoDing, Hebei, China
| | - Jiateng Zhao
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei, China
- Hebei Key Laboratory of Vegetable Germplasm Innovation and Utilization, BaoDing, Hebei, China
| | - Siyu Fang
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei, China
- Hebei Key Laboratory of Vegetable Germplasm Innovation and Utilization, BaoDing, Hebei, China
| | - Qian Zhang
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei, China
- Hebei Key Laboratory of Vegetable Germplasm Innovation and Utilization, BaoDing, Hebei, China
| | - Lanchun Nie
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei, China
- Hebei Key Laboratory of Vegetable Germplasm Innovation and Utilization, BaoDing, Hebei, China
- Collaborative Innovation Center of Vegetative Industry of Hebei Province, BaoDing, Hebei, China
| | - Wensheng Zhao
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei, China
- Hebei Key Laboratory of Vegetable Germplasm Innovation and Utilization, BaoDing, Hebei, China
- Collaborative Innovation Center of Vegetative Industry of Hebei Province, BaoDing, Hebei, China
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Camalle MD, Pivonia S, Zurgil U, Fait A, Tel-Zur N. Rootstock identity in melon-pumpkin graft combinations determines fruit metabolite profile. FRONTIERS IN PLANT SCIENCE 2023; 13:1024588. [PMID: 36762178 PMCID: PMC9907459 DOI: 10.3389/fpls.2022.1024588] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Accepted: 12/28/2022] [Indexed: 06/18/2023]
Abstract
Grafting has the potential to improve melon fruit yield and quality, but it is currently held that a lack of compatibility between the rootstock and scion compromises such an effect. To throw light on this subject, we studied melon-pumpkin graft combinations with different levels of compatibility to assess to the effect of the rootstock identity on melon fruit yield and quality, including total fruit ortho-diphenols, total flavonoids, and primary fruit metabolites. Melon cv. 'Kiran' (Ki) was grafted onto three pumpkin rootstocks, 'TZ-148' (TZ), 'Shimshon' (Sh), and '53006' (r53), characterized by high, moderate, and low compatibility, respectively. The non-grafted melon cultivar Ki was used as the control. The incompatible combination Ki/r53 gave the lowest fruit yield and the lowest average fruit weight. In that combination, the content of total ortho-diphenols increased vs. Ki and Ki/TZ and that of total flavonoids decreased vs. Ki/Sh. In addition, concentrations of the amino acids, glutamate, methionine, valine, alanine, glycine, and serine, increased in the pulp of the two compatible combinations, i.e., Ki/TZ and Ki/Sh, suggesting that rootstock identity and compatibility with melon Ki scion modulated amino acid synthesis. Our results show an association between rootstock identity (and level of compatibility with the scion) and an enhancement of fruit nutritional values, i.e., high concentrations of organic acids (determined as citrate, malate, fumarate, and succinate) and soluble carbohydrates (sucrose) were recorded in the pulp of the two compatible combinations, i.e., Ki/TZ and Ki/Sh.
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Affiliation(s)
- Maria Dolores Camalle
- The Albert Katz International School for Desert Studies, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, Israel
| | - Shimon Pivonia
- Arava Research and Development Center, Yair Experimental Station, Central and Northern Arava, Hazeva, Israel
| | - Udi Zurgil
- French Associates Institute for Agriculture and Biotechnology of Drylands, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, Israel
| | - Aaron Fait
- French Associates Institute for Agriculture and Biotechnology of Drylands, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, Israel
| | - Noemi Tel-Zur
- French Associates Institute for Agriculture and Biotechnology of Drylands, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer, Israel
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Hazrati H, Kudsk P, Ding L, Uthe H, Fomsgaard IS. Integrated LC-MS and GC-MS-Based Metabolomics Reveal the Effects of Plant Competition on the Rye Metabolome. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:3056-3066. [PMID: 35227064 DOI: 10.1021/acs.jafc.1c06306] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Plants compete with their neighbors about the limited resources available to them. Plants under induced stress resulting from competition may alter their metabolome to increase their resilience or enhance their defense mechanisms. In the present study, rye (Secale cereale) plants were cocultivated with different densities (3, 12, and 18 plants per pot) of Austrian pea (Pisum sativum subsp. arvense), hairy vetch (Vicia villosa), and Alexandrian clover (Trifolium alexandrinum L.) to elucidate the changes in the rye metabolome in response to the different levels of competition. Global metabolic profiling by liquid chromatography triple quadrupole tandem mass spectrometry (LC-QqQ-MS), liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS), and gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) was performed on rye plants, and the acquired data were analyzed using uni- and multivariate statistics. Targeted analysis showed that a high level of competition reduced the concentration of aglycone benzoxazinoids (BXs) and increased glycoside BXs in rye roots. Untargeted metabolomics analysis indicated an increase in the rye root content of the allelopathic compounds 4-hydroxybenzoic acid and uracil in response to competition. Untargeted analysis of rye shoots revealed that the plant competition increased the d-pyroglutamic acid, which is an elicitor of reactive oxygen species (ROS). Our results have enhanced the knowledge of the biochemical response of plant species to cocultivation.
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Affiliation(s)
- Hossein Hazrati
- Department of Agroecology, Aarhus University, Forsøgsvej 1, 4200 Slagelse, Denmark
- Department of Biomedicine, Aarhus University, 8200 Aarhus, Denmark
| | - Per Kudsk
- Department of Agroecology, Aarhus University, Forsøgsvej 1, 4200 Slagelse, Denmark
| | - Ling Ding
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 221, 2800 Kgs. Lyngby, Denmark
| | - Henriette Uthe
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Puschstrasse 4, 04103 Leipzig, Germany
| | - Inge S Fomsgaard
- Department of Agroecology, Aarhus University, Forsøgsvej 1, 4200 Slagelse, Denmark
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Brzozowski LJ, Gore MA, Agrawal AA, Mazourek M. Divergence of defensive cucurbitacins in independent Cucurbita pepo domestication events leads to differences in specialist herbivore preference. PLANT, CELL & ENVIRONMENT 2020; 43:2812-2825. [PMID: 32666553 DOI: 10.1111/pce.13844] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 06/23/2020] [Indexed: 05/19/2023]
Abstract
Crop domestication and improvement often concurrently affect plant resistance to pests and production of secondary metabolites, creating challenges for isolating the ecological implications of selection for specific metabolites. Cucurbitacins are bitter triterpenoids with extreme phenotypic differences between Cucurbitaceae lineages, yet we lack integrated models of herbivore preference, cucurbitacin accumulation, and underlying genetic mechanisms. In Cucurbita pepo, we dissected the effect of cotyledon cucurbitacins on preference of a specialist insect pest (Acalymma vittatum) for multiple tissues, assessed genetic loci underlying cucurbitacin accumulation in diverse germplasm and a biparental F2 population (from a cross between two independent domesticates), and characterized quantitative associations between gene expression and metabolites during seedling development. Acalymma vittatum affinity for cotyledons is mediated by cucurbitacins, but other traits contribute to whole-plant resistance. Cotyledon cucurbitacin accumulation was associated with population structure, and our genetic mapping identified a single locus, Bi-4, containing genes relevant to transport and regulation - not biosynthesis - that diverged between lineages. These candidate genes were expressed during seedling development, most prominently a putative secondary metabolite transporter. Taken together, these findings support the testable hypothesis that breeding for plant resistance to insects involves targeting genes for regulation and transport of defensive metabolites, in addition to core biosynthesis genes.
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Affiliation(s)
- Lauren J Brzozowski
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, New York, USA
| | - Michael A Gore
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, New York, USA
| | - Anurag A Agrawal
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, USA
| | - Michael Mazourek
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, New York, USA
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