绿豆种质资源苗期抗旱性鉴定

摘要

It is significant to identify and screen drought resistant mungbean germplasm resources at seedling stage for mungbean cultivars improvement and production in China, at the same time, which could provide some reference methods and basic infor-mation for developing “the technical specification of identification and evaluation for drought resistance in mungbean”. The indi-ces including survival rate of seedlings, wilt index, plant height, weight of fresh and dry leaf, relative water content, biomass weight and stress index were measured with the method of repeat drought stress in 70 accessions of mungbean resources. The survival rate of seedlings had significantly positive correlation between the first and the second drought stress, both wilt index and plant height had significantly negative correlation with survival rate. The survival rate of seedling under the first drought stress, wilt index and plant height were selected as suitable indices for drought resistance identification and evaluation based on correla-tion analysis. The various resistant accessions of mungbean germplasm resources screened by subordinative function analysis included 16 highly resistant, 20 resistant, 23 moderately resistant, eight susceptible and three highly susceptible. The drought re-sistance was evaluated based on the survival rate of seedling under the first drought stress, wilt index and plant height with the concordance rate of 70.0%, 58.6%, and 51.4% respectively as compared to the comprehensive evaluation. The survival rate of seedling under the first drought stress was recommended as a drought resistance index in screening a large number of germplasm resources ofmungbean.%鉴定筛选苗期抗旱绿豆种质，对改良绿豆品种抗旱性、促进绿豆产业发展具有重要意义，同时，也为“绿豆抗旱性鉴定评价技术规范”的制定提供方法和信息支撑。本研究以70份绿豆种质为材料，采用苗期反复干旱法，测定幼苗存活率、萎蔫指数、株高、叶片鲜重、叶片干重、叶片含水量、生物量和胁迫指数等指标，分析各指标间的相关性，结果显示第1次旱胁迫后的幼苗存活率与第2次旱胁迫后的幼苗存活率呈极显著正相关；萎蔫指数、株高与幼苗存活率呈极显著负相关，故遴选出第1次旱胁迫幼苗存活率、萎蔫指数和株高为绿豆苗期抗旱性评价的适宜指标。采用隶属函数法，综合分析划级，获得高抗旱种质16份、抗旱种质20份，中抗种质23份、敏感种质8份和极敏感种质3份。以第1次旱胁迫幼苗存活率、萎蔫指数和胁迫株高分别评价绿豆的抗旱性并与综合评价结果相比较，一致率分别为70.0%、58.6%和51.4%。认为第1次旱胁迫幼苗存活率可以作为大规模绿豆种质苗期抗旱筛选的鉴定指标。