【作者】 刘艳阳；

【导师】 崔党群；

【作者基本信息】 河南农业大学 ， 作物遗传育种， 2005， 硕士

【摘要】 作物的抗寒研究是抗逆研究的主要内容,寒害是影响小麦产量最重要的非生物因素之一,小麦抗寒性的机理非常复杂,不同时期表现不同的抗寒性。小麦抗寒性涉及到形态、生理、生化及遗传等多方面的因素,是一个复杂的数量性状。 本研究选用郑州8761×川育35050的F₁代花药培养的133个系的DH群体为材料,对小麦抗寒性鉴定指标进行筛选,并对抗寒相关性状进行QTL分析。结果表明: 1.幼苗习性与冻害程度呈显著正相关,幼苗越匍匐,抗寒性越强,幼苗习性可以作为小麦抗寒性鉴定的直观指标。 2.小麦叶片电解质外渗率随处理温度的降低呈现慢-快-慢的增加趋势,半致死低温Lt50具有特殊生理意义,可以用于抗寒性评价。不同低温处理下的小麦叶片电解质外渗率与冻害程度都呈极显著正相关,均可以作为小麦抗寒性鉴定的指标。 3.25℃下生长的小麦幼苗叶片经0℃低温处理2d后的SOD酶活性与冻害程度呈显著负相关,可以作为小麦抗寒性鉴定的指标;POD酶活性与冻害程度的相关性不大,只能作为抗寒鉴定的辅助指标。 4.25℃下生长的小麦幼苗叶片经0℃低温处理2d后的MDA含量与冻害程度呈显著正相关,可以作为小麦抗寒性鉴定的指标。 5.11个抗寒相关指标的隶属函数加权值与冻害程度呈极显著负相关,隶属函数法可以作为抗寒性综合评价的有效方法。 6.利用QTL Cartographer 2.0分析软件,运用复合区间作图法对DH群体抗寒相关性状进行OTL定位。幼苗习性、-9℃电解质外渗率和-12℃电解质外渗率均定位到1个QTL,都位于2A染色体,定位区间为Xgwm372～Xgwm249,贡献率分别为10.45%、15.61%和17.14%。-15℃电解质外渗率定位到1个QTL,位于4B染色体,定位区间为Xwmc48～DuPw043,贡献率为16.97%。-21℃电解质外渗率定位到1个QTL,位于2A染色体,定位区间为BARC208～Xgwm95,贡献率为19.8%。Lt50定位到2个QTL,分别位于1A染色体和4B染色体,定位区间分别为BARC158～BARC213和Xwmc48～DuPw043,贡献率分别为7.03%和14.55%;SOD酶活性定位到2个QTL,都位于5A染色体,定位区间分别为Xgwm304～Xgwm415和BARC241～BARC180,贡献率分别为8.54%和10.15%。更多还原

【Abstract】 Cold resistance is one of the most important no-biological factors diminishing wheat product. The cold resistance is various in different period. Wheat cold resistance is a complicated quantitative trait which involves morphological、 physiological 、 biological and hereditary elements, etc.In this study, a doubled haploid population, derived from anther culture of F₁ hybrid between Zhengzhou 8761 and Chuanyu 35050 was used as genetic material. The experiment aimed to study on appraisal indices of cold resistance, cold-resistance-index screening and the QTL mapping of the cold resistance related traits. The main experimental results were as follows:1. Growth habit was positively significant related with cold injury degree. The more decumbent the wheat was, the better the wheat cold resistance was. Growth habit could be used as an intuitionistic index for cold resistance.2. Electrolytic leakage of wheat leaves possessed a low-fast-low change in response to stable decrease of low temperature. This process was simulated by Logistic equation. Lt50 was approved to have special physical importance and could be used in cold evaluation. The electrolytic leakage of -6℃、 -9℃、 -12℃、 -15℃、 -18℃ and -21℃ were positively significant related with cold injury degree. Electrolytic leakage of each temperature were useful indices to appraise the cold resistance of wheat.3. SOD activity of wheat leaves cultivated at 25℃ temperature treated at 0℃ low temperature for 2 days was negatively significant related with cold injury degree. SOD activity was a useful index to appraise the cold resistance ability of wheat varieties.POD activity was insignificantly related with cold injury degree.POD activity was not suitable as evaluation index, but it might be a subordinate index.4. MDA content of wheat leaves cultivated at 25℃ temperature treated at 0℃ low temperature for 2 days was significant positively related with cold injury degree. MDA content could be used as a useful index to appraise cold resistance of wheat.5. A comprehensive evaluation on cold resistance of the DH population was given based on subordinate function value analysis. It showed that the weighed of subordinate function values of eleven indexes and cold injury degree coefficient was更多还原