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ARS Home » Southeast Area » Mayaguez, Puerto Rico » Tropical Crops and Germplasm Research » Research » Publications at this Location » Publication #295387

Title: Heat Tolerance

Author
item Porch, Timothy - Tim
item HALL,, A. - University Of California

Submitted to: Genomics and Breeding for Climate-Resilient Crops
Publication Type: Book / Chapter
Publication Acceptance Date: 3/15/2013
Publication Date: 6/15/2013
Citation: Porch Clay, T.G., Hall,, A.E. 2013. Heat Tolerance. In: Genomics and Breeding for Climate-Resilient Crops. Vol. 2:167-202.

Interpretive Summary: Predicted global warming would make it more difficult for farmers to achieve the increases in crop productivity (yield per unit area) needed to meet expected increases in demand for food and animal feed during this century. Due to projected increases in human population and the need for people who currently are poorly fed to receive more, higher quality food, farmers will need to produce twice as much food and feed crops on about the same area of cultivated land by the end of this century (World Bank 2010). It may be difficult to achieve this goal because the productivity of major crops has not increased in recent years. In this review, plant responses to high temperature during germination, vegetative growth and reproductive development to provide a physiological basis for choosing selection criteria in breeding for heat tolerance in annual crops. Those crops that produce grain and/or fruit are emphasized because most of the earlier research on heat tolerance has been conducted with these types of crops, and the cereals and grain legumes are major sources of food and feed. Studies of these types of crops provide an opportunity to determine whether heat stress is reducing reproductive yield through detrimental effects on the photosynthetic source of carbohydrate or through damage to reproductive development. Whether heat stress is mainly damaging the source or the sink or both processes will determine which heat tolerance selection strategies are most likely to enhance heat resistance. Methods for breeding for heat tolerance and those programs breeding for heat tolerance that have made significant progress are also reviewed.

Technical Abstract: Predicted global warming would make it more difficult for farmers to achieve the increases in crop productivity (yield per unit area) needed to meet expected increases in demand for food and animal feed during this century. Due to projected increases in human population and the need for people who currently are poorly fed to receive more, higher quality food, farmers will need to produce twice as much food and feed crops on about the same area of cultivated land by the end of this century (World Bank 2010). It may be difficult to achieve this goal because the productivity of major crops has not increased in recent years. In this review, plant responses to high temperature during germination, vegetative growth and reproductive development to provide a physiological basis for choosing selection criteria in breeding for heat tolerance in annual crops. Those crops that produce grain and/or fruit are emphasized because most of the earlier research on heat tolerance has been conducted with these types of crops, and the cereals and grain legumes are major sources of food and feed. Studies of these types of crops provide an opportunity to determine whether heat stress is reducing reproductive yield through detrimental effects on the photosynthetic source of carbohydrate or through damage to reproductive development. Whether heat stress is mainly damaging the source or the sink or both processes will determine which heat tolerance selection strategies are most likely to enhance heat resistance. Methods for breeding for heat tolerance and those programs breeding for heat tolerance that have made significant progress are also reviewed.