【作者】 张萍；

【导师】 白学良； 钟秀丽；

【作者基本信息】 内蒙古大学 ， 植物学， 2004， 硕士

【摘要】 在我国的黄淮、江淮等冬小麦主产区，拔节期霜冻害已经成为制约生产的主要因素之一。然而拔节期抗霜性的鉴定工作在国内外的研究报导还很少。本研究选取15个起源地和春化特性不同的品种，采用人工模拟霜冻害的方法，在幼穗分化的不同时期鉴定其抗霜性，查明幼穗分化进程中的低温敏感期。在敏感期进行品种间的抗霜力比较、排序。同时，对这15个品种的越冬期间的抗冻性进行了鉴定，分析抗冻性与抗霜性的关系。最后，分析磷脂酶D（PLD）在低温胁迫下活性的变化与冬小麦抗霜性的关系，从膜磷脂水解的角度探讨冬小麦的抗霜机理。研究结果表明：1)幼穗分化进入雌雄蕊期，抗霜力急剧下降，以后下降缓慢，表明雌雄蕊—药隔期为低温敏感期；2)选择药隔前期对不同品种的抗霜力进行比较发现，品种之间有很大差异，由弱到强的排序为：燕大1817＜晋麦47＜CA9722＜石家庄8号＜碧玛4号＜豫麦18＜中品1561＜Mi29＜皖麦38＜京411＜extreme＜J6₉₈₄₆；3)品种间抗冻性由弱到强的排序为：豫麦18＜濮阳9175＜云麦42＜燕大1817＜晋麦47＜石家庄8号＜CA9722＜碧玛4号＜Extreme＜京411＜中品1561＜J69846＜冀麦38＜皖麦38＜Mi29；4)品种抗冻性与抗霜性的比较发现，抗冻性强的品种并不一定抗霜性就强，因此无法用抗冻性推测品种的抗霜性；5)冬小麦抗寒性与低温胁迫下PLD的活性变化有关，低温处理数分钟内PLD迅速激活，抗寒力强的品种PLD的变化幅度比抗寒力弱的品种大。更多还原

【Abstract】 Frost injury of winter wheat that occurs during elongation growth stage has become one of the factors that restricted the improvement of the agriculturalproduction in Huanghuai and Jianghuai regions, the main producing areas of winterwheat in China. But fewer studies on evaluation of frost resistance in elongation growth stage had been reported up to now.In this study, 15 winter wheat varieties were selected as research materials, which differ in bred and cultivated places and vernalization trail. Firstly, frost resistance at different phases of young spike differentiation were tested in order to find the frost sensitive phases during development of young spikes. Then the frost resistance at sensitive phase were compared and sequenced among these species. Freezing-tolerance of the same species in wintering stage were also evaluated. After that, the relationship between frost resistance and wintering tolerance of winter wheat varieties was analysed only to explore if a strong relevance exist between them. At last, frost resistant mechanisms in winter wheat were primarily studied in regarding to membrane phospholipid hydrolysis. Especially, varying of phospholipase D (PLD) activity for winter wheat varieties with different cold resistance were measured undercold treatments.The results indicated: 1) Young spikes developed into frost sensitive period after stamens and pistils began to differentiate; 2) Wheat varieties differed in frost resistance of young spikes, compared in the same frost sensitive differentiation phase. Frost resistance of the varieties tested were ranked in an ascending sequence as follows: yanda1817 < jin47 < CA9722 < shjiazhuang8 < bima4 < yu18 < zhongpin1516 < Mi29 < wan38 < jing411 < extreme<J69846; 3) The freezing tolerance in wintering were also listed in an ascending sequence as: yumailS < puyang9175 < yun42 <yanda1817 < jin47 <shijiazhuang8 < CA9722 <bima42 < Extreme < jing411 < zhongpin1516 < J69846< ji38 < wan38 < Mi29; 4) Comparing 2) and 3), we found that the relationship between freezing tolerance and frost resistance was weak. So the frost-resistance of young spikes could not be estimated by testing freezing tolerance of the varieties; 5) Activation of PLD under cold stress affected the cold resistance of winter wheat. Only in a few minutes, PLD activities rapidly and transiently increased when suddenly subjected to low-temperature, with a higher level in those cold resistant varieties than that of the sensitive varieties.更多还原