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Abstract
Plant roots play a significant role in plant growth by exploiting soil resources via the uptake of water and nutrients. Root traits such as fine root diameter, specific root length, specific root area, root angle, and root length density are considered useful traits for improving plant productivity under drought conditions. Therefore, understanding interactions between roots and their surrounding soil environment is important, which can be improved through root phenotyping. With the advancement in technologies, many tools have been developed for root phenotyping. Canopy temperature depression (CTD) has been considered a good technique for field phenotyping of crops under drought and is used to estimate crop yield as well as root traits in relation to drought tolerance. Both laboratory and field-based methods for phenotyping root traits have been developed including soil sampling, mini-rhizotron, rhizotrons, thermography and non-soil techniques. Recently, a non-invasive approach of X-ray computed tomography (CT) has provided a break-through to study the root architecture in three dimensions (3-D). This review summarizes methods for root phenotyping. On the basis of this review, it can be concluded that root traits are useful characters to be included in future breeding programs and for selecting better cultivars to increase crop yield under water-limited environments.
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52
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Tricker PJ, ElHabti A, Schmidt J, Fleury D. The physiological and genetic basis of combined drought and heat tolerance in wheat. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:3195-3210. [PMID: 29562265 DOI: 10.1093/jxb/ery081] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 03/14/2018] [Indexed: 05/03/2023]
Abstract
Drought and heat stress cause losses in wheat productivity in major growing regions worldwide, and both the occurrence and the severity of these events are likely to increase with global climate change. Water deficits and high temperatures frequently occur simultaneously at sensitive growth stages, reducing wheat yields by reducing grain number or weight. Although genetic variation and underlying quantitative trait loci for either individual stress are known, the combination of the two stresses has rarely been studied. Complex and often antagonistic physiology means that genetic loci underlying tolerance to the combined stress are likely to differ from those for drought or heat stress tolerance alone. Here, we review what is known of the physiological traits and genetic control of drought and heat tolerance in wheat and discuss potential physiological traits to study for combined tolerance. We further place this knowledge in the context of breeding for new, more tolerant varieties and discuss opportunities and constraints. We conclude that a fine control of water relations across the growing cycle will be beneficial for combined tolerance and might be achieved through fine management of spatial and temporal gas exchange.
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Affiliation(s)
- Penny J Tricker
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, Australia
| | - Abdeljalil ElHabti
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, Australia
| | - Jessica Schmidt
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, Australia
| | - Delphine Fleury
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, Australia
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Sita K, Sehgal A, HanumanthaRao B, Nair RM, Vara Prasad PV, Kumar S, Gaur PM, Farooq M, Siddique KHM, Varshney RK, Nayyar H. Food Legumes and Rising Temperatures: Effects, Adaptive Functional Mechanisms Specific to Reproductive Growth Stage and Strategies to Improve Heat Tolerance. FRONTIERS IN PLANT SCIENCE 2017; 8:1658. [PMID: 29123532 PMCID: PMC5662899 DOI: 10.3389/fpls.2017.01658] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 09/08/2017] [Indexed: 05/20/2023]
Abstract
Ambient temperatures are predicted to rise in the future owing to several reasons associated with global climate changes. These temperature increases can result in heat stress- a severe threat to crop production in most countries. Legumes are well-known for their impact on agricultural sustainability as well as their nutritional and health benefits. Heat stress imposes challenges for legume crops and has deleterious effects on the morphology, physiology, and reproductive growth of plants. High-temperature stress at the time of the reproductive stage is becoming a severe limitation for production of grain legumes as their cultivation expands to warmer environments and temperature variability increases due to climate change. The reproductive period is vital in the life cycle of all plants and is susceptible to high-temperature stress as various metabolic processes are adversely impacted during this phase, which reduces crop yield. Food legumes exposed to high-temperature stress during reproduction show flower abortion, pollen and ovule infertility, impaired fertilization, and reduced seed filling, leading to smaller seeds and poor yields. Through various breeding techniques, heat tolerance in major legumes can be enhanced to improve performance in the field. Omics approaches unravel different mechanisms underlying thermotolerance, which is imperative to understand the processes of molecular responses toward high-temperature stress.
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Affiliation(s)
- Kumari Sita
- Department of Botany, Panjab University, Chandigarh, India
| | | | | | | | - P. V. Vara Prasad
- Sustainable Intensification Innovation Lab, Kansas State University, Manhattan, KS, United States
| | - Shiv Kumar
- International Center for Agricultural Research in the Dry Areas, Rabat, Morocco
| | - Pooran M. Gaur
- International Crops Research Institute for the Semi-Arid Tropics, Hyderabad, India
| | - Muhammad Farooq
- Department of Agronomy, University of Agriculture Faisalabad, Faisalabad, Pakistan
| | | | - Rajeev K. Varshney
- International Crops Research Institute for the Semi-Arid Tropics, Hyderabad, India
- The UWA Institute of Agriculture, University of Western Australia, Perth, WA, Australia
| | - Harsh Nayyar
- Department of Botany, Panjab University, Chandigarh, India
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54
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Xie Q, Fernando KMC, Mayes S, Sparkes DL. Identifying seedling root architectural traits associated with yield and yield components in wheat. ANNALS OF BOTANY 2017; 119:1115-1129. [PMID: 28200109 PMCID: PMC5604548 DOI: 10.1093/aob/mcx001] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 01/10/2017] [Indexed: 05/22/2023]
Abstract
Background and Aims Plant roots growing underground are critical for soil resource acquisition, anchorage and plant-environment interactions. In wheat ( Triticum aestivum ), however, the target root traits to improve yield potential still remain largely unknown. This study aimed to identify traits of seedling root system architecture (RSA) associated with yield and yield components in 226 recombinant inbred lines (RILs) derived from a cross between the bread wheat Triticum aestivum 'Forno' (small, wide root system) and spelt Triticum spelta 'Oberkulmer' (large, narrow root system). Methods A 'pouch and wick' high-throughput phenotyping pipeline was used to determine the RSA traits of 13-day-old RIL seedlings. Two field experiments and one glasshouse experiment were carried out to investigate the yield, yield components and phenology, followed by identification of quantitative trait loci (QTLs). Key Results There was substantial variation in RSA traits between genotypes. Seminal root number and total root length were both positively associated with grains m -2 , grains per spike, above-ground biomass m -2 and grain yield. More seminal roots and longer total root length were also associated with delayed maturity and extended grain filling, likely to be a consequence of more grains being defined before anthesis. Additionally, the maximum width of the root system displayed positive relationships with spikes m -2 , grains m -2 and grain yield. Ten RILs selected for the longest total roots exhibited the same effects on yield and phenology as described above, compared with the ten lines with the shortest total roots. Genetic analysis revealed 38 QTLs for the RSA, and QTL coincidence between the root and yield traits was frequently observed, indicating tightly linked genes or pleiotropy, which concurs with the results of phenotypic correlation analysis. Conclusions Based on the results from the Forno × Oberkulmer population, it is proposed that vigorous early root growth, particularly more seminal roots and longer total root length, is important to improve yield potential, and should be incorporated into wheat ideotypes in breeding.
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Affiliation(s)
- Quan Xie
- Division of Plant and Crop Sciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire LE12 5RD, UK
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Agricultural Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210 095, China
| | - Kurukulasuriya M. C. Fernando
- Division of Plant and Crop Sciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire LE12 5RD, UK
- Department of Crop Science, Faculty of Agriculture, University of Ruhuna, Mapalana, Kamburupitiya 81100, Sri Lanka
| | - Sean Mayes
- Division of Plant and Crop Sciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire LE12 5RD, UK
| | - Debbie L. Sparkes
- Division of Plant and Crop Sciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire LE12 5RD, UK
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55
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Pandey P, Irulappan V, Bagavathiannan MV, Senthil-Kumar M. Impact of Combined Abiotic and Biotic Stresses on Plant Growth and Avenues for Crop Improvement by Exploiting Physio-morphological Traits. FRONTIERS IN PLANT SCIENCE 2017; 8:537. [PMID: 28458674 PMCID: PMC5394115 DOI: 10.3389/fpls.2017.00537] [Citation(s) in RCA: 312] [Impact Index Per Article: 44.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 03/27/2017] [Indexed: 05/18/2023]
Abstract
Global warming leads to the concurrence of a number of abiotic and biotic stresses, thus affecting agricultural productivity. Occurrence of abiotic stresses can alter plant-pest interactions by enhancing host plant susceptibility to pathogenic organisms, insects, and by reducing competitive ability with weeds. On the contrary, some pests may alter plant response to abiotic stress factors. Therefore, systematic studies are pivotal to understand the effect of concurrent abiotic and biotic stress conditions on crop productivity. However, to date, a collective database on the occurrence of various stress combinations in agriculturally prominent areas is not available. This review attempts to assemble published information on this topic, with a particular focus on the impact of combined drought and pathogen stresses on crop productivity. In doing so, this review highlights some agriculturally important morpho-physiological traits that can be utilized to identify genotypes with combined stress tolerance. In addition, this review outlines potential role of recent genomic tools in deciphering combined stress tolerance in plants. This review will, therefore, be helpful for agronomists and field pathologists in assessing the impact of the interactions between drought and plant-pathogens on crop performance. Further, the review will be helpful for physiologists and molecular biologists to design agronomically relevant strategies for the development of broad spectrum stress tolerant crops.
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Affiliation(s)
- Prachi Pandey
- National Institute of Plant Genome ResearchNew Delhi, India
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56
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Valliyodan B, Ye H, Song L, Murphy M, Shannon JG, Nguyen HT. Genetic diversity and genomic strategies for improving drought and waterlogging tolerance in soybeans. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:1835-1849. [PMID: 27927997 DOI: 10.1093/jxb/erw433] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Drought and its interaction with high temperature are the major abiotic stress factors affecting soybean yield and production stability. Ongoing climate changes are anticipated to intensify drought events, which will further impact crop production and food security. However, excessive water also limits soybean production. The success of soybean breeding programmes for crop improvement is dependent on the extent of genetic variation present in the germplasm base. Screening for natural genetic variation in drought- and flooding tolerance-related traits, including root system architecture, water and nitrogen-fixation efficiency, and yield performance indices, has helped to identify the best resources for genetic studies in soybean. Genomic resources, including whole-genome sequences of diverse germplasms, millions of single-nucleotide polymorphisms, and high-throughput marker genotyping platforms, have expedited gene and marker discovery for translational genomics in soybean. This review highlights the current knowledge of the genetic diversity and quantitative trait loci associated with root system architecture, canopy wilting, nitrogen-fixation ability, and flooding tolerance that contributes to the understanding of drought- and flooding-tolerance mechanisms in soybean. Next-generation mapping approaches and high-throughput phenotyping will facilitate a better understanding of phenotype-genotype associations and help to formulate genomic-assisted breeding strategies, including genomic selection, in soybean for tolerance to drought and flooding stress.
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Affiliation(s)
- Babu Valliyodan
- Division of Plant Sciences and National Center for Soybean Biotechnology, University of Missouri, Columbia, MO 65211, USA
| | - Heng Ye
- Division of Plant Sciences and National Center for Soybean Biotechnology, University of Missouri, Columbia, MO 65211, USA
| | - Li Song
- Division of Plant Sciences and National Center for Soybean Biotechnology, University of Missouri, Columbia, MO 65211, USA
| | - MacKensie Murphy
- Division of Plant Sciences and National Center for Soybean Biotechnology, University of Missouri, Columbia, MO 65211, USA
| | - J Grover Shannon
- Division of Plant Sciences, University of Missouri-Fisher Delta Research Center, Portageville, MO 63873, USA
| | - Henry T Nguyen
- Division of Plant Sciences and National Center for Soybean Biotechnology, University of Missouri, Columbia, MO 65211, USA
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57
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Pandey P, Irulappan V, Bagavathiannan MV, Senthil-Kumar M. Impact of Combined Abiotic and Biotic Stresses on Plant Growth and Avenues for Crop Improvement by Exploiting Physio-morphological Traits. FRONTIERS IN PLANT SCIENCE 2017. [PMID: 28458674 DOI: 10.3389/flps.2017.00537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Global warming leads to the concurrence of a number of abiotic and biotic stresses, thus affecting agricultural productivity. Occurrence of abiotic stresses can alter plant-pest interactions by enhancing host plant susceptibility to pathogenic organisms, insects, and by reducing competitive ability with weeds. On the contrary, some pests may alter plant response to abiotic stress factors. Therefore, systematic studies are pivotal to understand the effect of concurrent abiotic and biotic stress conditions on crop productivity. However, to date, a collective database on the occurrence of various stress combinations in agriculturally prominent areas is not available. This review attempts to assemble published information on this topic, with a particular focus on the impact of combined drought and pathogen stresses on crop productivity. In doing so, this review highlights some agriculturally important morpho-physiological traits that can be utilized to identify genotypes with combined stress tolerance. In addition, this review outlines potential role of recent genomic tools in deciphering combined stress tolerance in plants. This review will, therefore, be helpful for agronomists and field pathologists in assessing the impact of the interactions between drought and plant-pathogens on crop performance. Further, the review will be helpful for physiologists and molecular biologists to design agronomically relevant strategies for the development of broad spectrum stress tolerant crops.
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Affiliation(s)
- Prachi Pandey
- National Institute of Plant Genome ResearchNew Delhi, India
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58
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Sita K, Sehgal A, HanumanthaRao B, Nair RM, Vara Prasad PV, Kumar S, Gaur PM, Farooq M, Siddique KHM, Varshney RK, Nayyar H. Food Legumes and Rising Temperatures: Effects, Adaptive Functional Mechanisms Specific to Reproductive Growth Stage and Strategies to Improve Heat Tolerance. FRONTIERS IN PLANT SCIENCE 2017. [PMID: 29123532 DOI: 10.3389/flps.2017.01658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Ambient temperatures are predicted to rise in the future owing to several reasons associated with global climate changes. These temperature increases can result in heat stress- a severe threat to crop production in most countries. Legumes are well-known for their impact on agricultural sustainability as well as their nutritional and health benefits. Heat stress imposes challenges for legume crops and has deleterious effects on the morphology, physiology, and reproductive growth of plants. High-temperature stress at the time of the reproductive stage is becoming a severe limitation for production of grain legumes as their cultivation expands to warmer environments and temperature variability increases due to climate change. The reproductive period is vital in the life cycle of all plants and is susceptible to high-temperature stress as various metabolic processes are adversely impacted during this phase, which reduces crop yield. Food legumes exposed to high-temperature stress during reproduction show flower abortion, pollen and ovule infertility, impaired fertilization, and reduced seed filling, leading to smaller seeds and poor yields. Through various breeding techniques, heat tolerance in major legumes can be enhanced to improve performance in the field. Omics approaches unravel different mechanisms underlying thermotolerance, which is imperative to understand the processes of molecular responses toward high-temperature stress.
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Affiliation(s)
- Kumari Sita
- Department of Botany, Panjab University, Chandigarh, India
| | | | | | | | - P V Vara Prasad
- Sustainable Intensification Innovation Lab, Kansas State University, Manhattan, KS, United States
| | - Shiv Kumar
- International Center for Agricultural Research in the Dry Areas, Rabat, Morocco
| | - Pooran M Gaur
- International Crops Research Institute for the Semi-Arid Tropics, Hyderabad, India
| | - Muhammad Farooq
- Department of Agronomy, University of Agriculture Faisalabad, Faisalabad, Pakistan
| | - Kadambot H M Siddique
- The UWA Institute of Agriculture, University of Western Australia, Perth, WA, Australia
| | - Rajeev K Varshney
- International Crops Research Institute for the Semi-Arid Tropics, Hyderabad, India
- The UWA Institute of Agriculture, University of Western Australia, Perth, WA, Australia
| | - Harsh Nayyar
- Department of Botany, Panjab University, Chandigarh, India
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59
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Fu G, Feng B, Zhang C, Yang Y, Yang X, Chen T, Zhao X, Zhang X, Jin Q, Tao L. Heat Stress Is More Damaging to Superior Spikelets than Inferiors of Rice ( Oryza sativa L.) due to Their Different Organ Temperatures. FRONTIERS IN PLANT SCIENCE 2016; 7:1637. [PMID: 27877180 PMCID: PMC5099171 DOI: 10.3389/fpls.2016.01637] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 10/17/2016] [Indexed: 05/05/2023]
Abstract
In general, the fertility and kernel weight of inferior spikelets of rice (Oryza Sativa L.) are obviously lower than those of superior spikelets, especially under abiotic stress. However, different responses to heat stress are seemed to show between the superior and inferior spikelet, and this response is scarcely documented that the intrinsic factors remain elusive. In order to reveal the mechanism underlying, two rice plants with different heat tolerance were subjected to heat stress of 40°C at anthesis. The results indicated that a greater decrease in fertility and kernel weight was observed in superior spikelets compared to inferior spikelets. This decrease was primarily ascribed to their different organ temperatures, in which the temperature of the superior spikelets was significantly higher than that of inferior spikelets. We inferred the differences in canopy temperature, light intensity and panicle types, were the primary reasons for the temperature difference between superior and inferior spikelets. Under heat stress, the fertility and kernel weight of superior and inferior spikelets decreased as the panicle numbers per plant were reduced, which was accompanied by significantly increasing the canopy temperatures. Thus, it was suggested that the rice plant with characteristic features of an upright growth habit and loose panicles might be more susceptible to heat stress resulting from their higher canopy and spikelets temperatures.
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Affiliation(s)
- Guanfu Fu
- State Key Laboratory of Rice Biology, China National Rice Research InstituteHangzhou, China
| | - Baohua Feng
- State Key Laboratory of Rice Biology, China National Rice Research InstituteHangzhou, China
| | | | | | | | | | | | | | - Qianyu Jin
- State Key Laboratory of Rice Biology, China National Rice Research InstituteHangzhou, China
| | - Longxing Tao
- State Key Laboratory of Rice Biology, China National Rice Research InstituteHangzhou, China
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60
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Reynolds M, Langridge P. Physiological breeding. CURRENT OPINION IN PLANT BIOLOGY 2016; 31:162-71. [PMID: 27161822 DOI: 10.1016/j.pbi.2016.04.005] [Citation(s) in RCA: 110] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 04/08/2016] [Accepted: 04/14/2016] [Indexed: 05/18/2023]
Abstract
Physiological breeding crosses parents with different complex but complementary traits to achieve cumulative gene action for yield, while selecting progeny using remote sensing, possibly in combination with genomic selection. Physiological approaches have already demonstrated significant genetic gains in Australia and several developing countries of the International Wheat Improvement Network. The techniques involved (see Graphical Abstract) also provide platforms for research and refinement of breeding methodologies. Recent examples of these include screening genetic resources for novel expression of Calvin cycle enzymes, identification of common genetic bases for heat and drought adaptation, and genetic dissection of trade-offs among yield components. Such information, combined with results from physiological crosses designed to test novel trait combinations, lead to more precise breeding strategies, and feed models of genotype-by-environment interaction to help build new plant types and experimental environments for future climates.
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Affiliation(s)
- Matthew Reynolds
- Global Wheat Program, International Maize and Wheat Improvement Center (CIMMYT), Mexico, D.F., Mexico.
| | - Peter Langridge
- School of Agriculture, Food and Wine, University of Adelaide, Adelaide, Australia
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61
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Driedonks N, Rieu I, Vriezen WH. Breeding for plant heat tolerance at vegetative and reproductive stages. PLANT REPRODUCTION 2016; 29:67-79. [PMID: 26874710 PMCID: PMC4909801 DOI: 10.1007/s00497-016-0275-9] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/21/2016] [Indexed: 05/19/2023]
Abstract
KEY MESSAGE Thermotolerant crop research. Global warming has become a serious worldwide threat. High temperature is a major environmental factor limiting crop productivity. Current adaptations to high temperature via alterations to technical and management systems are insufficient to sustain yield. For this reason, breeding for heat-tolerant crops is in high demand. This review provides an overview of the effects of high temperature on plant physiology, fertility and crop yield and discusses the strategies for breeding heat-tolerant cultivars. Generating thermotolerant crops seems to be a challenging task as heat sensitivity is highly variable across developmental stages and processes. In response to heat, plants trigger a cascade of events, switching on numerous genes. Although breeding has made substantial advances in developing heat-tolerant lines, the genetic basis and diversity of heat tolerance in plants remain largely unknown. The development of new varieties is expensive and time-consuming, and knowledge of heat tolerance mechanisms would aid the design of strategies to screen germplasm for heat tolerance traits. However, gains in heat tolerance are limited by the often narrow genetic diversity. Exploration and use of wild relatives and landraces in breeding can increase useful genetic diversity in current crops. Due to the complex nature of plant heat tolerance and its immediate global concern, it is essential to face this breeding challenge in a multidisciplinary holistic approach involving governmental agencies, private companies and academic institutions.
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Affiliation(s)
- Nicky Driedonks
- Department of Molecular Plant Physiology, Institute for Water and Wetland Research, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Ivo Rieu
- Department of Molecular Plant Physiology, Institute for Water and Wetland Research, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands.
| | - Wim H Vriezen
- Bayer CropScience Vegetable Seeds, PO Box 4005, 6080 AA, Haelen, The Netherlands
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62
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Rebetzke GJ, Bonnett DG, Reynolds MP. Awns reduce grain number to increase grain size and harvestable yield in irrigated and rainfed spring wheat. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:2573-86. [PMID: 26976817 PMCID: PMC4861010 DOI: 10.1093/jxb/erw081] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Genotypic variation in ear morphology is linked to differences in photosynthetic potential to influence grain yield in winter cereals. Awns contribute to photosynthesis, particularly under water-limited conditions when canopy assimilation is restricted. We assessed performance of up to 45 backcross-derived, awned-awnletted NILs representing four diverse genetic backgrounds in 25 irrigated or rainfed, and droughted environments in Australia and Mexico. Mean environment grain yields were wide-ranging (1.38-7.93 t ha(-1)) with vegetative and maturity biomass, plant height, anthesis date, spike number, and harvest index all similar (P >0.05) for awned and awnletted NILs. Overall, grain yields of awned-awnletted sister-NILs were equivalent, irrespective of yield potential and genetic background. Awnletted wheats produced significantly more grains per unit area (+4%) and per spike (+5%) reflecting more fertile spikelets and grains in tertiary florets. Increases in grain number were compensated for by significant reductions in grain size (-5%) and increased frequency (+0.8%) of small, shrivelled grains ('screenings') to reduce seed-lot quality of awnletted NILs. Post-anthesis canopies of awnletted NILs were marginally warmer over all environments (+0.27 °C) but were not different and were sometimes cooler than awned NILs at cooler air temperatures. Awns develop early and represented up to 40% of total spikelet biomass prior to ear emergence. We hypothesize that the allocation of assimilate to large and rapidly developing awns decreases spikelet number and floret fertility to reduce grain number, particularly in distal florets. Individual grain size is increased to reduce screenings and to increase test weight and milling quality, particularly in droughted environments. Despite the average reduction in grain size, awnless lines could be identified that combined higher grain yield with larger grain size, increased grain protein concentration, and reduced screenings.
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Affiliation(s)
- G J Rebetzke
- CSIRO Agriculture, PO Box 1600, Canberra, ACT 2601, Australia
| | - D G Bonnett
- CSIRO Agriculture, PO Box 1600, Canberra, ACT 2601, Australia Bayer Crop Science, 6693 90th St Sabin, MN 56580 USA CIMMYT Int. Apdo. Postal 6-641, 06600 México, DF, Mexico
| | - M P Reynolds
- CIMMYT Int. Apdo. Postal 6-641, 06600 México, DF, Mexico
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63
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Reynolds MP, Quilligan E, Aggarwal PK, Bansal KC, Cavalieri AJ, Chapman SC, Chapotin SM, Datta SK, Duveiller E, Gill KS, Jagadish KS, Joshi AK, Koehler AK, Kosina P, Krishnan S, Lafitte R, Mahala RS, Muthurajan R, Paterson AH, Prasanna BM, Rakshit S, Rosegrant MW, Sharma I, Singh RP, Sivasankar S, Vadez V, Valluru R, Vara Prasad P, Yadav OP. An integrated approach to maintaining cereal productivity under climate change. GLOBAL FOOD SECURITY-AGRICULTURE POLICY ECONOMICS AND ENVIRONMENT 2016. [DOI: 10.1016/j.gfs.2016.02.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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64
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Maccaferri M, El-Feki W, Nazemi G, Salvi S, Canè MA, Colalongo MC, Stefanelli S, Tuberosa R. Prioritizing quantitative trait loci for root system architecture in tetraploid wheat. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:1161-78. [PMID: 26880749 PMCID: PMC4753857 DOI: 10.1093/jxb/erw039] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Optimization of root system architecture (RSA) traits is an important objective for modern wheat breeding. Linkage and association mapping for RSA in two recombinant inbred line populations and one association mapping panel of 183 elite durum wheat (Triticum turgidum L. var. durum Desf.) accessions evaluated as seedlings grown on filter paper/polycarbonate screening plates revealed 20 clusters of quantitative trait loci (QTLs) for root length and number, as well as 30 QTLs for root growth angle (RGA). Divergent RGA phenotypes observed by seminal root screening were validated by root phenotyping of field-grown adult plants. QTLs were mapped on a high-density tetraploid consensus map based on transcript-associated Illumina 90K single nucleotide polymorphisms (SNPs) developed for bread and durum wheat, thus allowing for an accurate cross-referencing of RSA QTLs between durum and bread wheat. Among the main QTL clusters for root length and number highlighted in this study, 15 overlapped with QTLs for multiple RSA traits reported in bread wheat, while out of 30 QTLs for RGA, only six showed co-location with previously reported QTLs in wheat. Based on their relative additive effects/significance, allelic distribution in the association mapping panel, and co-location with QTLs for grain weight and grain yield, the RSA QTLs have been prioritized in terms of breeding value. Three major QTL clusters for root length and number (RSA_QTL_cluster_5#, RSA_QTL_cluster_6#, and RSA_QTL_cluster_12#) and nine RGA QTL clusters (QRGA.ubo-2A.1, QRGA.ubo-2A.3, QRGA.ubo-2B.2/2B.3, QRGA.ubo-4B.4, QRGA.ubo-6A.1, QRGA.ubo-6A.2, QRGA.ubo-7A.1, QRGA.ubo-7A.2, and QRGA.ubo-7B) appear particularly valuable for further characterization towards a possible implementation of breeding applications in marker-assisted selection and/or cloning of the causal genes underlying the QTLs.
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Affiliation(s)
- Marco Maccaferri
- Department of Agricultural Sciences (DipSA), University of Bologna, 40127 Bologna, Italy
| | - Walid El-Feki
- Department of Agricultural Sciences (DipSA), University of Bologna, 40127 Bologna, Italy Department of Crop Sciences, Faculty of Agriculture, Alexandria University, 23714 Alexandria, Egypt
| | - Ghasemali Nazemi
- Department of Agricultural Sciences (DipSA), University of Bologna, 40127 Bologna, Italy Department of Agriculture, Hajiabad Branch, Islamic Azad University, 21100 Hajiabad, Iran
| | - Silvio Salvi
- Department of Agricultural Sciences (DipSA), University of Bologna, 40127 Bologna, Italy
| | - Maria Angela Canè
- Department of Agricultural Sciences (DipSA), University of Bologna, 40127 Bologna, Italy
| | - Maria Chiara Colalongo
- Department of Agricultural Sciences (DipSA), University of Bologna, 40127 Bologna, Italy
| | - Sandra Stefanelli
- Department of Agricultural Sciences (DipSA), University of Bologna, 40127 Bologna, Italy
| | - Roberto Tuberosa
- Department of Agricultural Sciences (DipSA), University of Bologna, 40127 Bologna, Italy
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Valluru R, Reynolds MP, Lafarge T. Food security through translational biology between wheat and rice. Food Energy Secur 2015. [DOI: 10.1002/fes3.71] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Ravi Valluru
- Global Wheat Program International Maize and Wheat Improvement Center (CIMMYT) El Batan Mexico
| | - Matthew P. Reynolds
- Global Wheat Program International Maize and Wheat Improvement Center (CIMMYT) El Batan Mexico
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Gao F, Wen W, Liu J, Rasheed A, Yin G, Xia X, Wu X, He Z. Genome-Wide Linkage Mapping of QTL for Yield Components, Plant Height and Yield-Related Physiological Traits in the Chinese Wheat Cross Zhou 8425B/Chinese Spring. FRONTIERS IN PLANT SCIENCE 2015; 6:1099. [PMID: 26734019 PMCID: PMC4683206 DOI: 10.3389/fpls.2015.01099] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 11/22/2015] [Indexed: 05/18/2023]
Abstract
Identification of genes for yield components, plant height (PH), and yield-related physiological traits and tightly linked molecular markers is of great importance in marker-assisted selection (MAS) in wheat breeding. In the present study, 246 F8 RILs derived from the cross of Zhou 8425B/Chinese Spring were genotyped using the high-density Illumina iSelect 90K single nucleotide polymorphism (SNP) assay. Field trials were conducted at Zhengzhou and Zhoukou of Henan Province, during the 2012-2013 and 2013-2014 cropping season under irrigated conditions, providing data for four environments. Analysis of variance (ANOVA) of agronomic and physiological traits revealed significant differences (P < 0.01) among RILs, environments, and RILs × environments interactions. Broad-sense heritabilities of all traits including thousand kernel weight (TKW), PH, spike length (SL), kernel number per spike (KNS), spike number/m(2) (SN), normalized difference in vegetation index at anthesis (NDVI-A) and at 10 days post-anthesis (NDVI-10), SPAD value of chlorophyll content at anthesis (Chl-A) and at 10 days post-anthesis (Chl-10) ranged between 0.65 and 0.94. A linkage map spanning 3609.4 cM was constructed using 5636 polymorphic SNP markers, with an average chromosome length of 171.9 cM and marker density of 0.64 cM/marker. A total of 866 SNP markers were newly mapped to the hexaploid wheat linkage map. Eighty-six QTL for yield components, PH, and yield-related physiological traits were detected on 18 chromosomes except 1D, 5D, and 6D, explaining 2.3-33.2% of the phenotypic variance. Ten stable QTL were identified across four environments, viz. QTKW.caas-6A.1, QTKW.caas-7AL, QKNS.caas-4AL, QSN.caas-1AL.1, QPH.caas-4BS.2, QPH.caas-4DS.1, QSL.caas-4AS, QSL.caas-4AL.1, QChl-A.caas-5AL, and QChl-10.caas-5BL. Meanwhile, 10 QTL-rich regions were found on chromosome 1BS, 2AL (2), 3AL, 4AL (2), 4BS, 4DS, 5BL, and 7AL exhibiting pleiotropic effects. These QTL or QTL clusters are tightly linked to SNP markers, with genetic distances to the closest SNPs ranging from 0 to 1.5 cM, and could serve as target regions for fine mapping, candidate gene discovery, and MAS in wheat breeding.
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Affiliation(s)
- Fengmei Gao
- Key Laboratory of Soybean Biology, Soybean Research Institute, Ministry of Education, Northeast Agricultural UniversityHarbin, China
- National Wheat Improvement Center, Institute of Crop Science, Chinese Academy of Agricultural SciencesBeijing, China
- Keshan Sub-Academy, Heilongjiang Academy of Agricultural SciencesKeshan, China
| | - Weie Wen
- National Wheat Improvement Center, Institute of Crop Science, Chinese Academy of Agricultural SciencesBeijing, China
| | - Jindong Liu
- National Wheat Improvement Center, Institute of Crop Science, Chinese Academy of Agricultural SciencesBeijing, China
| | - Awais Rasheed
- National Wheat Improvement Center, Institute of Crop Science, Chinese Academy of Agricultural SciencesBeijing, China
- International Maize and Wheat Improvement Center (CIMMYT) China Office, c/o Chinese Academy of Agricultural SciencesBeijing, China
| | - Guihong Yin
- Zhoukou Academy of Agricultural SciencesZhoukou, China
| | - Xianchun Xia
- National Wheat Improvement Center, Institute of Crop Science, Chinese Academy of Agricultural SciencesBeijing, China
| | - Xiaoxia Wu
- Key Laboratory of Soybean Biology, Soybean Research Institute, Ministry of Education, Northeast Agricultural UniversityHarbin, China
- *Correspondence: Xiaoxia Wu
| | - Zhonghu He
- National Wheat Improvement Center, Institute of Crop Science, Chinese Academy of Agricultural SciencesBeijing, China
- International Maize and Wheat Improvement Center (CIMMYT) China Office, c/o Chinese Academy of Agricultural SciencesBeijing, China
- Zhonghu He
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67
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Langridge P, Reynolds MP. Genomic tools to assist breeding for drought tolerance. Curr Opin Biotechnol 2014; 32:130-135. [PMID: 25531270 DOI: 10.1016/j.copbio.2014.11.027] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 11/28/2014] [Indexed: 11/30/2022]
Abstract
Water deficit or drought stress is a major limitation to crop production globally. Plant breeders have used a wide range of technologies to successfully breed varieties that perform well under the growth conditions for their target environments but they are always seeking new opportunities to enhance rates of genetic gain. Under drought, yield is determined by the integration of variable levels of water deficit across the developmental life of the crop. Genomics technologies were seen as a path to understand the genetic and environmental complexity of drought stress. To be relevant to breeding programs, genomic studies must consider the nature of drought stress in the target environment and use plant material and phenotyping techniques that relate to field conditions.
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Affiliation(s)
- Peter Langridge
- Australian Centre for Plant Functional Genomics, University of Adelaide, Urrbrae SA 5064, Australia.
| | - Matthew P Reynolds
- International Maize and Wheat Improvement Centre, CIMMYT, El Batan 56130, Texcoco, Mexico
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