【作者】 李衍素；

【导师】 于贤昌；

【作者基本信息】 山东农业大学 ， 蔬菜学， 2006， 硕士

【摘要】 以我国北方地区常用的18个豇豆品种为试材,通过夏季田间品种比较、人工气候室及光照培养箱苗期试验,研究了高温胁迫下豇豆(Vigna unguiculata W.)生长和生理特性的变化,筛选出了耐热性存在明显差异的两个豇豆品种:早优一号和优选之豇28-2。然后以两者幼苗为试材,研究了高温胁迫对豇豆叶片膜伤害、保护酶类、非酶抗氧化系统和光合作用的影响,探讨了豇豆耐热的生理机制。具体研究结果如下:1.豇豆品种耐热性比较:先进行田间结果期试验,然后于人工气候室和光照培养箱进行苗期试验。结果表明,所有参比品种中,早优一号较耐热,而优选之豇28-2耐热性较差。2.对豇豆耐热生理机制的研究表明:2.1豇豆的光合适温范围为36℃～38℃,不同豇豆品种光合适温范围有所差异。2.2随高温胁迫时间的延长,豇豆叶片的热害指数上升,相对电导率和丙二醛含量增加,而叶绿素含量下降。但耐热品种的热害指数相对较小,相对电导率和丙二醛含量增加相对较少,叶绿素含量下降较慢。说明高温胁迫下,耐热性较强的豇豆品种其质膜和叶绿体受害程度较轻,2.3高温胁迫下,豇豆pro和可溶性糖含量均明显升高,但耐热品种pro和可溶性糖含量均明显高于不耐热品种,在高温胁迫下具有更高的渗透调节能力。高温胁迫下,豇豆叶片可溶性蛋白质含量下降,而游离氨基酸含量增加。但不同品种可溶性蛋白质和游离氨基酸含量无明显差异。说明高温胁迫下,可溶性蛋白质和游离氨基酸含量会随胁迫时间的变化而发生相应的变化,但二者含量均与豇豆的耐热性没有直接关系。2.4高温胁迫下,早优一号和优选之豇28-2二者SOD、POD和CAT活性均先增加后减少,Vc含量则持续增加,而早优一号SOD、POD和CAT活性和Vc含量则始终高于不耐热品种。说明在高温胁迫下,耐热性较强的豇豆品种具有较高的保护酶活性和非酶保护物质含量,其保护能力较强。2.5高温胁迫下,早优一号和优选之豇28-2叶片的Pn迅速下降,Ci更多还原

【Abstract】 The changes of growth and physiological characters of 18 cowpea (Vigna unguiculata W.) varieties commonly cultured in north China were studied. The fruit stage researches were actualized in farmland in summer and the seedling experiments were done in phytotron and light growth incubator. Two varieties which evidently different in their heat tolerance were selected, that is zaoyouNO.1 and youxuanzhijiang28-2. Seedlings of those two varieties were used to study the effects of heat stress on the membrane damage, changes of protective enzymes, non-enzyme antioxidants and photosynthesis. And the mechanism of high temperature endurance of cowpea was discussed. The main results were as follow:1. Heat-tolerance comparison of cowpea:Fruit stage experiment in farmland in summer was actualized first, and then the seedling experiments in phytotron and light growth incubator were done. The results showed that the heat-tolerance of zaoyouNo.1 was highest, but that of youxuanzhijiang28-2 was low relatively among the 18 varieties.2. Study on mechanism of cowpea heat-tolerance2.1 The suitable temperature range for photosynthesis of cowpea was 36℃～38℃, and different cowpea varieties behaved different.2.2 As time of heat-stress went by, heat index, relative conductivity and MDA content of cowpea increased, while the chlorophyll content decreased. But the heat index, relative conductivity and MDA content of zaoyouNo.1 were lower apparently than those of youxuanzhijiang28-2, while the chlorophyll content of zaoyouNo.1 was higher. It showed that under high temperature stress, the damages to plasma membrane and chloroplast of heat-tolerant cowpea variety were not more serious than to heat-sensitive variety.2.3 Under high temperature stress, the content of proline and soluble sugar of cowpea increased evidently, and those of zaoyouNo.1 were higher than those of youxuanzhijiang28-2, which showed that the ability of osmotic更多还原