不同基因型小麦品种倒春寒抗性分析及其评价

Analysis and Evaluation of Resistance to Late Spring Coldness in Different Genotypes of Wheat

倒春寒是限制我国黄淮和长江中下游冬麦区小麦高产稳产的重要因素。为了明确黄淮和长江中下游冬麦区24个主栽或近年来审定的小麦品种倒春寒抗性强弱,在拔节期利用人工气候室进行冷冻胁迫处理(两种强度:L1,-4℃/1 d;L2,-2℃/2 d),对这些品种叶片受冻指数、幼穗冻伤率、产量等指标进行调查,以鉴选抗倒春寒的小麦品种,同时对品种倒春寒抗性(叶片受冻指数和幼穗冻伤率)与品种冬春性、越冬期抗寒性(叶片受冻指数)和农艺性状(如茎长、茎粗、SPAD等)的关系进行了分析。结果表明,各品种叶片受冻指数、幼穗冻伤率及产量降幅在L1和L2下的表现有所不同。在L1和L2下,淮麦20、江麦816和济麦22的叶片受冻指数、幼穗冻伤率和主茎产量降幅整体上表现较低;而连麦8号、淮麦20、柳麦618和镇麦12的产量降幅表现较低。虽然小麦品种倒春寒抗性、冬春性和越冬期抗寒性间存在密切关系,但单个品种的三者之间并无必然关联。拔节期农艺指标难以反映小麦品种的倒春寒抗性。

Late spring coldness is an important factor limiting the high and stable yield of wheat in Huanghuai and middle and lower reaches of Yangtze River winter wheat regions.Planting varieties with resistance to spring coldness is an effective way to reduce the harm of spring coldness.In this study,24 wheat varieties were used as research materials and subjected to freezing stress(L1,-4℃/1 d;L2,-2℃/2 d).The leaf freezing index,young ear frostbite rate,yield,and other indicators were investigated in order to identify wheat varieties resistant to late spring coldness.In addition,the relationship between resistance to late spring coldness(leaf freezing index and young ear frostbite rate)and winter-spring characteristic,cold resistance at the overwintering(leaf freezing index)and agronomic characters(such as stem length,stem diameter,SPAD,etc.)were analyzed.The results showed that the leaf freezing index,the young ear frostbite rate,and yield decline of different varieties were different under L1 and L2 treatments.Huaimai 20,Jiangmai 816 and Jimai 22 showed lower leaf freezing index,young ear frostbite rate and main stem yield decline under both freezing treatments.However,the total yield of Lianmai 8,Huaimai 20,Liumai 618 and Zhenmai 12 showed relatively lower reduction under both freezing treatments.Although there was a close relationship among the resistance to late spring coldness,winter and spring habitat,and cold resistance at the overwintering of wheat varieties,there was no necessary correlation among the three as far as a single variety was concerned.Agronomic traits at jointing stage can not reflect the resistance of wheat varieties to late spring coldness.