乳熟期淹涝胁迫对水稻形态特性及产量的影响

摘要

In order to explore the change of m orphologicalcharacteristics and yield of tw o-line hybrid rice under subm ergence stress at m ilky stage,w e chose the com m only used rice variety X iang Fengyou 103 asthe testm aterial,designed a series oftreatm ents w ith different w aterdepth and subm ergence duration,and analyzed the sensitivity ofm orphologicalcharacteristicsand yield featuresofrice atm ilky stage through m easuring changesin the num berofgreen leaves,aerialrootsstatus,lodging situation and yield structure statusbefore and afterthe inundation.The results show ed that① in the sam e depth of subm ergence,subm ergence duration tim e and the num ber of changed green leaves w ere negatively related. ② The ratio of aerial roots to stem w as negatively correlated w ith subm ergence depth and positively correlated w ith the flooding tim e.M oreover,the low er the internode w as,the phenom enon of aerialroots w as m ore obvious.③ U nder differentsubm ergence stress backgrounds,lodging occurred atm ilky stage w as rootlodging.The deeperthe w aterw as and the longerthe subm ergence lasted,lodging phenom enon w as m ore obvious.④ In term s ofthe yield structure,the deeperthe w aterw as and the longerthe subm ergence lasted,the im pacton the yield w as larger,w hich w ere m ainly show ed up as increased rates ofem pty grain and blighted grain as w ellas decreased 1000-grain w eight.Fora 9-day com plete inundation,blighted grain rate w as as high as 23.8% ,17.7% higherthan that ofthe control;1000-grain w eightw asonly 19.0g,4.2g lighterthan thatofthe control.%为探讨乳熟期不同淹涝胁迫环境下两系杂交稻形态特征、产量结构的变化，以晚稻常规品种湘丰优103为供试品种，设计不同淹水深度、不同淹水时间的淹水胁迫处理，通过测定淹水前后绿叶数的变化、气生根情况、倒伏情况、产量结构情况，分析乳熟期形态特征的敏感性及产量特点。结果表明，相同的淹涝深度，淹涝持续时间与绿叶数变化呈极显著负相关；气生根茎数的比率与淹水深度呈负相关，与淹水时间呈极显著正相关；且稻株茎节越低，气生根现象越明显；乳熟期的倒伏为根倒伏，深度越深、持续时间越长，倒伏现象越明显；产量结构方面，淹水深度越深、淹水时间越长，对产量的影响越大，主要表现为空壳率、秕粒率升高，千粒重下降，全淹9 d，秕粒率高达23.8%，比对照高17.7个百分点，千粒重仅有19.0 g，比对照低4.2 g。