大豆生理指标与抗旱性关系的研究

为探讨大豆生理指标与抗旱性的关系,并筛选出最适合的大豆抗旱鉴定生理指标,选用同一大豆杂交组合产生的4个品系为试验材料73-1(尖叶白花)、73-2(圆叶紫花)、73-3(圆叶白花)、73-4(尖叶紫花)],于营养生长期干旱胁迫条件下,测定其叶片相对含水量、脯氨酸含量、叶绿素含量、相对电导率、渗透势等生理指标;收获后测定株高、百粒重、分枝数、结荚数、单株粒重等农艺性状,并利用抗旱隶属函数值的分析方法,对各品系的抗旱级别进行了划分;进而分析了各品系生理指标与其抗旱性的关系。结果表明:4个品系抗旱性从强到弱的次序为:73-2(圆叶紫花)、73-1(尖叶白花)、73-3(圆叶白花)、73-4(尖叶紫花)。大豆叶片相对含水量、叶绿素含量、脯氨酸含量与抗旱性呈正相关;而相对电导率、渗透势与抗旱性呈负相关。对各指标综合比较发现,叶绿素含量、叶片相对含水量和渗透势与抗旱性的关系更为密切,可以作为大豆抗旱鉴定的最佳生理指标。

Research on Relationship between Physiological Indexes and Drought Resistance of Soybeans

The objective of present study was to probe the relationship between physiological in-dexes and drought resistance of different soybean strains and select the most appropriate drought-resistant physiological indexes according to reality of strains.Four strains from the same cross were selected,namely 73-1(sharp leaves and white flowers),73-2(round leaves and purple flowers),73-3(round leaves and white flowers),73-4(sharp leaves and purple flowers).In the condition of drought stress in the nutritional growth period,physiological indexes such as relative water content,contents of proline and chlorophyll,relative electric conductivity and osmotic potential were determined.After harvesting,data of agronomic characters such as plant height,hundred-seed weight,branch quantity,total pods and seed weight of per plant were evaluated.Drought-resistant classes of strains were divided by subordinate function values.Also,relationship between physiological indexes and drought resistance of different strains was analyzed and analysis of correlation and regression was applied.The results were summarized as follows:The order of drought-resistance of the four strains was as following:73-2(round leaf and purple flower),73-1(sharp leaf and white flower),73-3(round leaf and white flower),73-4(sharp leaf and purple flower).Relative water content,contents of chlorophyll and proline were positively correlated with drought resistance,whereas relative electric conductivity,osmotic potential were negatively correlated with drought resistance.By comprehensive comparison of various indexes,it was found that relative water content,chlorophyll content and osmotic potential showed closer relationship with drought resistance,which indicated that they could be used as the best physiological indexes for drought-resistant evaluation.