312 recombinant inbred lines （RILs） in F9 from a cross between a overwintering cold-tolerant germplasm resource Glutinous rice 89-1（Gr 89-1） and a cold-sensitive variety Shuhui 527 was used for quantitative trait ...312 recombinant inbred lines （RILs） in F9 from a cross between a overwintering cold-tolerant germplasm resource Glutinous rice 89-1（Gr 89-1） and a cold-sensitive variety Shuhui 527 was used for quantitative trait locus （QTL） analysis. The scores of percent ratooning germinability （PRG） and overwintering germinability （POG） were evaluated. The overwintering germination rate of axillary buds was scored to represent the overwintering germinability. Two significant QTLs （qPRG-4 and qPRG-7） on chromosomes 4 and 7 were detected and explained 8.3 and 7.2% of the total phenotypic variation, respectively. Three significant QTLs （qPOG-2, qPOG-3 and qPOG-7） were identified and mapped on chromosomes 2, 3, and 7, respectively. These QTLs contributed 9.6, 6.7, and 17.8% of phenotypic variations, respectively. A comparative analysis using SSR markers closely linked to the three QTLs for the overwintering revealed cold-tolerant individuals, which harbour the Glutinous rice 89-1 alleles at RM7110, RM250, RM418, and RM232, had a high percent overwintering germinability, while cold-sensitive individuals, which carry Shuhui 527 alleles at these loci, had a low percent overwintering germinability in the F2 population of Shuhui 527/Glutinous rice 89-1. This study demonstrated the utility of these SSR markers for selection of overwintering germinability genotypes.展开更多
Cold stress is a major environmental factor influencing crop yield,quality,and geographic distribution.With the increasing frequency of extreme weather events globally,the challenges to food security posed by cold are...Cold stress is a major environmental factor influencing crop yield,quality,and geographic distribution.With the increasing frequency of extreme weather events globally,the challenges to food security posed by cold are becoming more urgent(Lesk et al.,2016).A key strategy to mitigate cold damage is to deepen our understanding of the molecular mechanisms underlying plant responses to low temperatures,identify critical cold-tolerant genes,and then precisely breed coldtolerant varieties through molecular design.As the world’s most important staple crop,maize is native to tropical and subtropical regions and is highly sensitive to cold stress(Allen and Ort,2001).展开更多
Landscape changes are known to exacerbate the impacts of climate change. As such, understanding the combined effect of climate and landscape on agroecosystems is vital if we are to maintain the fimction of agroecosyst...Landscape changes are known to exacerbate the impacts of climate change. As such, understanding the combined effect of climate and landscape on agroecosystems is vital if we are to maintain the fimction of agroecosystems. This study aimed to elucidate the effects of agricultural landscape complexity on the microclimate and thermal tolerance of an aphid pest to better understand how landscape and climate may interact to affect the thermal tolerance of pest species within the context of global climate change. Meteo- rological data were measured at the landscape level, and cereal aphids （Sitobion avenae, Metopolophium dirhodum and Rhopalosiphum padi） sampled, from contrasting landscapes （simple and complex） in winter 2013/2014 and spring 2014 in cereal fields of Brittany, France. Aphids were returned to the laboratory and the effect of landscape of origin on aphid cold tolerance （as determined by CTmin） was investigated. Results revealed that local landscape complexity significantly affected microclimate, with simple homogenous landscapes being on average warmer, but with greater temperature variation. Landscape complexity was shown to impact aphid cold tolerance, with aphids from complex land- scapes being more cold tolerant than those from simple landscapes in both winter and spring, but with differences among species. This study highlights that future changes to land use could have implications for the thermal tolerance and adaptability of insects. Fur- thermore, not all insect species respond in a similar way to microhabitat and microclimate, which could disrupt important predator-prey relationships and the ecosystem service they provide.展开更多
基金supported by the Rice Key Project of Chongqing,China (CSTC2011AB1076)the Foundation Project of Chongqing Education Commission (KJ110623)+1 种基金the Doctor Foundation of Chongqing Normal University,China (10LR028)the Plants Breeding Project of Chongqing,China (CSTC2010AA1033)
文摘312 recombinant inbred lines （RILs） in F9 from a cross between a overwintering cold-tolerant germplasm resource Glutinous rice 89-1（Gr 89-1） and a cold-sensitive variety Shuhui 527 was used for quantitative trait locus （QTL） analysis. The scores of percent ratooning germinability （PRG） and overwintering germinability （POG） were evaluated. The overwintering germination rate of axillary buds was scored to represent the overwintering germinability. Two significant QTLs （qPRG-4 and qPRG-7） on chromosomes 4 and 7 were detected and explained 8.3 and 7.2% of the total phenotypic variation, respectively. Three significant QTLs （qPOG-2, qPOG-3 and qPOG-7） were identified and mapped on chromosomes 2, 3, and 7, respectively. These QTLs contributed 9.6, 6.7, and 17.8% of phenotypic variations, respectively. A comparative analysis using SSR markers closely linked to the three QTLs for the overwintering revealed cold-tolerant individuals, which harbour the Glutinous rice 89-1 alleles at RM7110, RM250, RM418, and RM232, had a high percent overwintering germinability, while cold-sensitive individuals, which carry Shuhui 527 alleles at these loci, had a low percent overwintering germinability in the F2 population of Shuhui 527/Glutinous rice 89-1. This study demonstrated the utility of these SSR markers for selection of overwintering germinability genotypes.
基金supported by the National Natural Science Foundation of China(32170620).
文摘Cold stress is a major environmental factor influencing crop yield,quality,and geographic distribution.With the increasing frequency of extreme weather events globally,the challenges to food security posed by cold are becoming more urgent(Lesk et al.,2016).A key strategy to mitigate cold damage is to deepen our understanding of the molecular mechanisms underlying plant responses to low temperatures,identify critical cold-tolerant genes,and then precisely breed coldtolerant varieties through molecular design.As the world’s most important staple crop,maize is native to tropical and subtropical regions and is highly sensitive to cold stress(Allen and Ort,2001).
文摘Landscape changes are known to exacerbate the impacts of climate change. As such, understanding the combined effect of climate and landscape on agroecosystems is vital if we are to maintain the fimction of agroecosystems. This study aimed to elucidate the effects of agricultural landscape complexity on the microclimate and thermal tolerance of an aphid pest to better understand how landscape and climate may interact to affect the thermal tolerance of pest species within the context of global climate change. Meteo- rological data were measured at the landscape level, and cereal aphids （Sitobion avenae, Metopolophium dirhodum and Rhopalosiphum padi） sampled, from contrasting landscapes （simple and complex） in winter 2013/2014 and spring 2014 in cereal fields of Brittany, France. Aphids were returned to the laboratory and the effect of landscape of origin on aphid cold tolerance （as determined by CTmin） was investigated. Results revealed that local landscape complexity significantly affected microclimate, with simple homogenous landscapes being on average warmer, but with greater temperature variation. Landscape complexity was shown to impact aphid cold tolerance, with aphids from complex land- scapes being more cold tolerant than those from simple landscapes in both winter and spring, but with differences among species. This study highlights that future changes to land use could have implications for the thermal tolerance and adaptability of insects. Fur- thermore, not all insect species respond in a similar way to microhabitat and microclimate, which could disrupt important predator-prey relationships and the ecosystem service they provide.
