半野生棉抗黄萎病筛选及根系分泌物对黄萎病菌的影响

摘要

对陆地棉7个野生种系的220份材料进行黄萎病菌的抗性筛选,用8份不同抗性材料进行了根系分泌物分析.从220份材料中筛选出18份抗黄萎病材料.根系分泌物研究表明,抗病品种根系分泌物对黄萎病菌菌丝生长及孢子萌发均具有抑制作用,而感病品种根系分泌物对其则有促进作用.另外通过对根系分泌物中氨基酸和可溶性糖的分析发现,抗病品种根系分泌物中氨基酸种类少于感病品种,并且抗病品种根系分泌物中氨基酸总量和可溶性糖含量显著少于感病品种.同时发现,精氨酸为抗病品种特有氨基酸.%In present study, 18 accessions which were resistant or tolerant to Verticillium wilt were screened out from 220 acces-sions of all seven races of Gossypium hirsutum. Eight accessions were chosen to analyze the effects of their root exudates on the wilt pathogen, from which four are resistant and four are susceptible, respectively. Higher resistant accessions and resistant ones which are valuable should be found. The resistance mechanism of Gossypium hirsutum can be known partly. Screening on Verti-cillium wilt resistance used 5 classification criteria, Which included amino acid and saccharide contents, hypha growth and spore germination setting-out in resistance mechanism shading. Results showed the root exudates from resistant accessions restrained the hypha growth and spore germination but the exudates from susceptible ones reversed. The amino acid and saccharide con-tents in root exudates from resistant accessions were obviously less than those from susceptible accessions. The kinds of amino acid in root exudates from resistant accessions were clearly less than those from susceptible ones, and very interestingly, arginine existed peculiarly in resistant semiwild accessions.