Heat stress seriously affects wheat production in many regions of the world. At present, heat tolerance research remains one of the least understood fields in wheat genetics and breeding and there is a lack of effecti...Heat stress seriously affects wheat production in many regions of the world. At present, heat tolerance research remains one of the least understood fields in wheat genetics and breeding and there is a lack of effective methods to quantify heat stress and heat tolerance in different wheat cultivars. The objective of this study was to use various wheat cultivars to evaluate stress intensity(δ) and a new method for quantification of heat tolerance and compare this technique with three other currently utilized methods. This new parameter for heat tolerance quantification is referred to as the heat tolerance index(HTI) and is an indicator of both yield potential and yield stability. Heat treatments were applied in a controlled setting when anthesis had been reached for 80% of the wheat. The stress intensity evaluation indicated heat shock was the main factor associated with kernel weight reduction while grain yield reduction was mainly associated with chronic high temperature. The methods evaluation showed that a temperature difference of 5°C from natural temperatures was a suitable heat treatment to compare to the untreated controls. HTI was positively correlated with yield under heat stress(r=0.8657, δ=0.15, in 2009–2010; r=0.8418, δ=0.20, in 2010–2011; P<0.01), and negatively correlated with yield reduction rate(r=–0.8344, in 2009–2010; r=–0.7158, in 2010–2011; P<0.01). The results of this study validated the use of HTI and temperature difference control for quantifying wheat heat tolerance that included the yield potential and the stability of different wheat cultivars under heat stress. Additionally, 10 wheat cultivars showed high HTI and should be further tested for their heat confirming characteristics for use in wheat heat tolerance breeding.展开更多
Heat stress negatively affects wheat production in many regions of the world.At present,sensitivity to heat stress remains one of the least understood aspects of wheat genetics and breeding,and measures for preventing...Heat stress negatively affects wheat production in many regions of the world.At present,sensitivity to heat stress remains one of the least understood aspects of wheat genetics and breeding,and measures for preventing heat stress are understudied.In this study,we used three cultivars of winter wheat(GY2018,SL02-1 and SY20)to evaluate the effect of heat stress at different days after anthesis(DAA)on yield and quality.Heat stability of the cultivars were analyzed and evaluated for the effects of two kinds of regulators on wheat under heat stress conditions.Heat treatment at 7 DAA led to the most substantial reduction in yield while GY2018 had the best heat stability with respect to yield,and demonstrated the most positive effects on several quality traits including protein content,sedimentation volume and glutenin and gliadin contents.Heat treatment at 14 DAA had the least reduction in yield,while SY20 had the best heat stability with respect to yield and heat treatment had minimal effects on quality.Heat treatment at 21 DAA had only a limited effect on yield,while SL02-1 had the best heat stability with respect to yield,but it showed the most negative effects on quality.Stable time at 14 DAA and protein content at 21 DAA can be used as indicators for detecting the stability of quality under heat stress.Among the three studied cultivars,SY20 was the most sensitive to heat stress with the stable time decreasing from 26.4 to 9.1 min,a higher sedimentation volume at 7 DAA,and a lowerγ-gliadin content which increased 2.4-fold under high-temperature treatment.The addition of various regulators had different effects:potassium dihydrogen phosphate(KDP)was more protective of yield with heat stress at 7 DAA,while Duntianbao(DTB)had better effects on quality with heat stress at 21 DAA.展开更多
基金partially supported by the Generation Challenge Program,CIMMYT(International Maize and Wheat Improvement Center)(GCP,G7010.02.01)the earmarked fund for China Agriculture Research System(CARS-3-2-3)the National Key Technology R&D Program of China(2016YFD0100502,2016YFD0300407)
文摘Heat stress seriously affects wheat production in many regions of the world. At present, heat tolerance research remains one of the least understood fields in wheat genetics and breeding and there is a lack of effective methods to quantify heat stress and heat tolerance in different wheat cultivars. The objective of this study was to use various wheat cultivars to evaluate stress intensity(δ) and a new method for quantification of heat tolerance and compare this technique with three other currently utilized methods. This new parameter for heat tolerance quantification is referred to as the heat tolerance index(HTI) and is an indicator of both yield potential and yield stability. Heat treatments were applied in a controlled setting when anthesis had been reached for 80% of the wheat. The stress intensity evaluation indicated heat shock was the main factor associated with kernel weight reduction while grain yield reduction was mainly associated with chronic high temperature. The methods evaluation showed that a temperature difference of 5°C from natural temperatures was a suitable heat treatment to compare to the untreated controls. HTI was positively correlated with yield under heat stress(r=0.8657, δ=0.15, in 2009–2010; r=0.8418, δ=0.20, in 2010–2011; P<0.01), and negatively correlated with yield reduction rate(r=–0.8344, in 2009–2010; r=–0.7158, in 2010–2011; P<0.01). The results of this study validated the use of HTI and temperature difference control for quantifying wheat heat tolerance that included the yield potential and the stability of different wheat cultivars under heat stress. Additionally, 10 wheat cultivars showed high HTI and should be further tested for their heat confirming characteristics for use in wheat heat tolerance breeding.
基金partially supported by the National Key R&D Program of China(2016YFD0300407 and 2016YFD0100502)the earmarked fund for China Agriculture Research System(CARS-03-2-1)+1 种基金the Science and Technology Innovation Project of Hebei Academy of Agriculture and Forestry Sciences,China(4-01-03)the Hebei Science and Technology Support Plan,China(16226320D)。
文摘Heat stress negatively affects wheat production in many regions of the world.At present,sensitivity to heat stress remains one of the least understood aspects of wheat genetics and breeding,and measures for preventing heat stress are understudied.In this study,we used three cultivars of winter wheat(GY2018,SL02-1 and SY20)to evaluate the effect of heat stress at different days after anthesis(DAA)on yield and quality.Heat stability of the cultivars were analyzed and evaluated for the effects of two kinds of regulators on wheat under heat stress conditions.Heat treatment at 7 DAA led to the most substantial reduction in yield while GY2018 had the best heat stability with respect to yield,and demonstrated the most positive effects on several quality traits including protein content,sedimentation volume and glutenin and gliadin contents.Heat treatment at 14 DAA had the least reduction in yield,while SY20 had the best heat stability with respect to yield and heat treatment had minimal effects on quality.Heat treatment at 21 DAA had only a limited effect on yield,while SL02-1 had the best heat stability with respect to yield,but it showed the most negative effects on quality.Stable time at 14 DAA and protein content at 21 DAA can be used as indicators for detecting the stability of quality under heat stress.Among the three studied cultivars,SY20 was the most sensitive to heat stress with the stable time decreasing from 26.4 to 9.1 min,a higher sedimentation volume at 7 DAA,and a lowerγ-gliadin content which increased 2.4-fold under high-temperature treatment.The addition of various regulators had different effects:potassium dihydrogen phosphate(KDP)was more protective of yield with heat stress at 7 DAA,while Duntianbao(DTB)had better effects on quality with heat stress at 21 DAA.
