六个丝瓜品种对南方根结线虫的抗性

根结线虫病是我国瓜类蔬菜的主要病害,选育抗病品种是有效防控该病的主要措施。结合田间调查与室内检测重复验证,采用病情指数、繁殖系数等多种抗根结线虫评价方法对丝瓜抗性进行分析,以便为瓜类蔬菜根结线虫多指标抗性评价提供科学参考和借鉴,为丝瓜与其他瓜类蔬菜抗根结线虫的材料创新与新品种(含砧木)培育奠定基础。综合评价供试丝瓜品种对南方根结线虫的抗性水平,经形态学特征鉴定,重庆地区丝瓜的病原线虫为南方根结线虫(Meloidogyne incognita);6个丝瓜品种1、2、5、6、32、33号的田间病情指数分别为65.3、12.5、55.3、18.9、32.0、34.3,根际线虫繁殖系数分别为1.28、0.46、1.12、0.57、0.73、0.78,每5 mm根段组织线虫数量分别为34、4、18、7、9、10 条,每100 mm幼嫩根段上早期平均检出根结数分别为12.2、2.1、14.8、0、0、0。2020年田间和温室试验结果与2019年抗性评价结果基本一致;以上4项指标相互印证,趋于一致,能够作为抗南方根结线虫的评价指标;4项指标数据综合评价,判定2号、6号材料为高抗(HR),32号、33号材料为抗性(R),1号、5号材料为感病(S)。

Resistance evaluation of six towel gourd varieties to Meloidogyne incognita

Root-knot nematode disease is one of important diseases on melon crops production in China, utilization of resistant materials is regarded as one successful way for the disease control. The purpose of this study was to provide scientific reference for more convincing resistance evaluation of towel gourd varieties even other crops varieties based on multiple indicators, and it will lay a foundation for breeding new root-knot nematode resistant varieties (including rootstocks) of luffa and melon vegetables. The resistance of six towel gourd materials were evaluated based on three indicators from field incidence investigation and laboratory tests from 2019—2020. The main results of the study were as follows: the pathogen identification of morphological characteristics showed the parasitic nematode was Meloidogyne incognita. The disease index (DI)of six towel gourd materials (No.1, No.2, No.5, No.6, No.32, No.33) were 65.3, 12.5, 55.3, 18.9, 32.0 and 34.3, respectively. The reproduction coefficient of M. incognita in the rhizosphere of six materials were correspondingly calculated as 1.28, 0.46, 1.12, 0.57, 0.73 and 0.78. While, the pathogenic nematode numbers in root tissues per 5 mm of six kinds of host were found to be 34, 4, 18, 7, 9 and 10 individuals.The average number of root nodules per 100 mm detected in the young root segments of six kinds of host were 12.2,2.1,14.8,0,0 and 0 individuals.The main results of field tests and artificial inoculation in greenhouse conducted in 2020, were consistent with those of field tests in 2019. The above results could be summarized that the materials No.2 and No.6 were high resistant (HR) to M. incognita, while No.32 and No.33 were resistant materials (R), the materials No.1 and No.5 were susceptible (S) to root-knot nematodes (M. incognita).