棉花品种抗黄萎病性与体内生化成分相关分析

STUDIES ON THE BIOCHEMICAL COMPONENTS IN COTTON RELATED TO THE RESISTANCE TO VERTICILLIUM DAHLIAE

对棉花不同抗感黄萎病性品种生化成分分析结果表明:棉花品种在无菌土中体内可溶性还原糖含量相应地高于接菌土中的含量。蕾期抗耐品种平均含量为2.276％,高于感性品种的1.417％,而铃期趋势相反。叶片单宁含量高于根部。在无菌土中,抗耐品种叶片单宁含量平均为3.58％,高于感病品种的3.28％;而在接菌条件下趋势相反。根部棉酚含量显著高于叶部,但两者极显著相关。在无菌土和接菌土中,抗性品种棉酚含量均高于耐性品种,而耐性品种又高于感性品种。棉株体内棉酚含量与棉花品种抗黄萎病性显著正相关。同工酶谱测定显示,过氧化物酶在抗感品种的无病症叶片中,酶带特征基本一致,叶片显症后表现主酶带区加宽,主酶带数增多,变化趋势与症状严重度正相关。在显症条件下,抗性品种酯酶同工酶活性略强于感性品种;与无症叶相比,显症叶的SOD酶带数由原来的4—6条减少至3—4条,抗性品种的酶带数少于感性品种1—2条。

More than fifteen different resistant varieties of cotton were studied at squaring and boll stages. The concentrations of soluble reducing sugar in cotton grown on non-inoculated soil were higher than that on the inoculated soil. At squaring stage, the average concentrations of soluble reducing sugar in resistant and tolerant varieties was 2. 276% , higher than that in susceptible varieties, 1. 417%; but at the boll stage, the trend was reversed. The contents of tannin in roots were lower than that in leaves. Under the non-inoculated condition, the resistant and tolerant varieties showed higher tannin contents than susceptible varieties; under inoculated condition, however, the trend was opposite. Comparing with leaves, roots had higher gossypol level. Under both soil conditions , resistant, tolerant and susceptible varieties were ranked respectively according to the gossypol concentrations. There was a significant positive correlation between the gossypol concentrations and resistance level of varieties to Verticillium dahliae.The resistant level and susceptible varieties showed the same pattern of peroxidese isozyme. When the symptom occured, the leaves turned to higher peroxidese activities, and the change was positively related to the symptom severities. In the leaves with symptom, resistant varieties showed slightly higher activities of esterase isozyme than that in susceptible ones. The number of bands of superoxide dismutase in resistant varieties was 1 - 2 bands less than that of susceptible varieties.