【摘要】 在水分胁迫条件下对两个粳型水稻披垂叶突变体品系及其与常规籼、粳品种的杂交后代(F1、F2)进行苗期耐旱性鉴定,并测定了旱种条件下突变体及其杂交后代不同生育期过氧化物酶(POD)、过氧化氢酶(CAT)活性的变化以及相关农艺性状的特征。结果表明:两个水稻披垂叶突变体MR304和MR312的苗期耐旱性均为中抗;MR312与7个品种的11个杂交后代(F1)中,仅有文稻2号/MR312组合的苗期耐旱性为高抗,MR312/滇香籼1号为中抗;在昆明旱种条件下,突变体及其杂交后代POD和CAT的活性分别在孕穗期和抽穗期最高,其中4个组合(银光/MR312、农安稻/MR312、文稻2号/MR312和MR312/滇香籼1号)F1孕穗期POD或抽穗期CAT的活性最强,株高、分蘖、穗长趋于正常。该研究揭示了利用水稻披垂叶突变体产生的F1杂种优势可增强杂交稻大田期的耐旱性;孕穗期的POD活性和抽穗期的CAT活性是鉴定杂交后代F1和F2植株大田期耐旱性的重要指标。更多还原

【Abstract】 This experiment investigated the drought tolerance at seedling stage in two japonica drooping leaf mutants and its crossing progenies (F1 and F2) under water stress, analyzed the variations in two enzyme activity (POD and CAT) at different growth stages in mutants and progenies, and measured the correlated agronomic traits. The study showed that the two drooping leaf mutants MR304 and MR312 were medium resistant to drought at seedling stage, and only Wendao 2/MR312 was high resistant and MR312/Dianxiangxian 1 was medium resistant to the drought among eleven progenies from the cross of MR312 and seven cultivars. The activity of POD and CAT were the highest in booting stage and heading stage, respectively, whereas the activity of POD at booting stage or CAT at heading stage in F1 of four combinations (Yinguang/MR312, Nongandao/MR312, Wendao 2/MR312 and MR312/Dianxiangxian 1) were the highest, and these combinations trended to be the normal with plant height, effective panicle, panicle length at Kunming under the dry-land cropping. This study revealed that we could utilize the F1 heterosis derived from the cross of drooping leaf mutants and conventional varieties and the activities of POD at booting stage and CAT at heading stage were the important index to evaluate the drought tolerance of crossing progenies F1 and F2 during growth period from tillering to harvesting in the field.更多还原