马铃薯腐烂线虫不同群体同工酶表型与致病力研究

    对国内不同地理来源的10个马铃薯腐烂线虫群体进行同工酶表型研究,同时在2个中抗甘薯茎线虫病品种(苏薯9号、宁薯9-9)上测定马铃薯腐烂线虫群体致病力、繁殖力、雌雄比(性比)、甘薯薯块鲜重损失量.结果表明:①10个群体苹果酸脱氢酶(MDH)酶谱分为2个酶型, 酶型Ⅰ的相对迁移率(Rf值)约为0.21、0.26;酶型Ⅱ的Rf值约为0.21、0.26、0.31,而酯酶染色不成形;②在P=0.05水平上,各群体间的致病力、繁殖力、性比差异显著,其中致病力最高的群体来自河北廊坊DeHB,对苏薯9号的致病力为75%;③在苏薯9号和宁薯9-9上,各线虫群体致病力与线虫繁殖力呈正相关;④偏相关分析显示,在苏薯9号上不同线虫群体繁殖力与性比呈负相关,相关系数为-0.213,而在宁薯9-9上不同群体繁殖力与性比呈显著正相关,相关系数为0.901,说明寄主品种的改变对线虫群体性别分化影响显著;⑤在抗甘薯茎线虫病和保鲜力方面,宁薯9-9分别比苏薯9号高33.48%和19.86%.

Research on isozyme phenotypes and pathogenicity of Ditylenchus destructor in sweet potato

Two isozymes from 10 populations of sweet potato stem nematode, Ditylenchus destructor, were analyzed, as well as the weight loss of sweet potato, pathogenicity, fecundity and sex ratio of these 10 populations by inoculation test in two varieties of sweet potato. The results show that among the 10 populations, there were three main bands of malate dehydrogenase (MDH), which were corresponding to two different phenotypes. Rf was about 0.21, 0.26 and the other was 0.21, 0.26 and 0.31, but esterase (EST) was no band. The pathogenicity, fecundity and sex ratio of the 10 populations were significant at the P=0.05 level, the highest pathogenicity population was from DeHB. There were positive relationships between fecundity and pathogenicity on the Sushu No.9 and Ningshu 9-9. Partial correlation analysis showed that there was negative relationship between fecundity and sex ratio of the 10 populations on the Sushu No.9 and significant positive relationship on the Ningshu 9-9, and their coefficients were -0.213, 0.901, respectively, indicating that the sex differentiation of D. destructor was significantly affected by the different varieties of sweet potato. In addition, the Ningshu 9-9 was 33.48% higher than the Sushu No.9 in the resistant to D. destructor, and 19.86% higher in preservation.