中晚熟玉米杂交组合耐旱性鉴定与评价

Identification and Evaluation of Drought Resistance of Middle-late Mature Maize of Cross Combination

【目的】鉴定评价56个中晚熟玉米杂交组合的耐旱性。【方法】采用NCⅡ不完全双列杂交设计,以9个自选育中晚熟骨干玉米自交系为母本,6个不同遗传背景的中晚熟骨干自交系为父本,配制54个杂交组合,以郑单958和先玉335为对照品种,通过田间直接鉴定法,研究中晚熟玉米不同基因型材料在正常灌溉和干旱胁迫条件下与耐旱性有关的生育、形态、产量等性状差异,鉴定评价不同杂交组合的耐旱性,筛选对玉米耐旱性贡献较大的耐旱性鉴定指标。【结果】干旱敏感型杂交组合的具体表现为植株株高、穗位高降低,穗位叶叶绿素含量下降,雌雄花期间隔增大,雄穗减小,果穗短小,秃尖增大,穗行数和行粒数减少,千粒重和穗粒重降低,最终造成产量下降。参试杂交组合中耐旱性极强的组合为新自8549×ZPL717、新自8717×吉853、新自7425×吉853、先玉335、新自618×郑58、新自7425×PH4CV,耐旱指数分别为1.44、1.44、1.28、1.08、1.08、1.00。【结论】单穗粒重、穗粗、穗位叶叶绿素含量、行粒数、穗长、穗行数、千粒重和品种耐旱性关系密切,可作为耐旱性评价的一级筛选指标。筛选出3个组合的耐旱性优于先玉335,分别是新自8549×ZPL717、新自8717×吉853、新自7425×吉853。

[Objective] The study aims to identify and analyze the drought resistance of 56 varieties of maize of cross combination.[Method] In this study the inbred lines if maize consisting of 9 external （♀）maize and middle-late mature maize（♂） were tested in the NC Ⅱ incomplete parallel cross design,54 hybrid combination were bred,Zhengdan 958 and Xianyu 335 were control variety,the method of the direct identification in field was used under normal irrigation condition and drought stress to compare and evaluate growth period traits,morphological traits,yield traits,etc.related to drought resistance in order to evaluate and identify drought resistance in the hope of screening effective evaluation index to make great contributions to drought resistance.[Result] It was showed that maize of cross combination was sensitive：plant height,ear height,chlorophyll content decreased and anthesis-silking interval was prolonged.Tassel became shorter,ear became shorter and smaller,bare top became longer,kernels number and ear rows became less,1000-kernels weight and ear grain weight was reduced,which led to yield decline.By using the method of production index of drought tolerance,the results showed that the fortissimo of drought tolerance of the maize of cross combination were Xinzi8549 × ZPL717,Xinzi8717 × Ji853,Xinzi7425 × Ji853,Xianyu335,Xinzi618 ×Zheng58,Xinzi7425 × PH4CV,and their drought tolerance indexes were 1.44,1.44,1.28,1.08,1.08,1.00,respectively.[Conclusion] The results showed that grain yield per plant,ear diameter,chlorophyll content,kernels per row,ear length,rows per ear,1 000-kernels weight were closely related,which can be used as first-rank indexes for evaluation of drought tolerance of maize varieties.The fortissimo drought tolerance of 3 cross combinations screened out was Xinzi8549 × ZPL717,Xinzi8717 × Ji853,Xinzi7425 × Ji853,their drought tolerance was stronger than Sianyu335.