云南省澜沧县林下三七根结线虫病害调查与侵染来源分析

Investigation and Infection Source Analysis of Root Knot Nematode Disease of Panax notoginseng in Lancang County,Yunnan Province

【目的】明确云南省澜沧县林下有机三七种植基地及育苗基地三七根结线虫病病原种类及来源,为该地区三七根结线虫病的防治奠定基础。【方法】采用系统调查法对澜沧县林下三七种植基地、育苗基地的三七及其周边相同生境下的杂草进行根结线虫病害发生情况调查和病原线虫种类鉴定。【结果】3个基地中大塘子三七育苗基地的根结线虫危害最严重,发病率高达66.82%;其次是林下基地,而哈果马育苗基地危害相对较轻。经收集鉴定,危害林下和育苗基地三七和杂草的病原根结线虫为北方根结线虫(Meloidogyne hapla);在思茅松林下分布杂草97种,其中发生根结线虫病的杂草有紫茎泽兰和积雪草2种,根据杂草的分布丰度和根结线虫寄生的程度可以判断紫茎泽兰是林下三七根结线虫病的主要中间寄主。两育苗基地的杂草类型基本一致,分布杂草124种,其中发生根结线虫病的杂草有溪黄草、紫茎泽兰、鬼针草、六棱菊、豆茶决明、野茼蒿、香薷、一点红、积雪草、草玉梅和豨莶等11种,根据杂草的分布丰度和根结线虫寄生的程度可以判断鬼针草、野茼蒿和紫茎泽兰是三七育苗基地三七根结线虫病的主要中间寄主。【结论】云南省澜沧县林下及育苗基地危害三七及杂草的病原线虫均为北方根结线虫(M.hapla),种苗带病是林下三七根结线虫病发生的主要原因,而苗圃地土壤中的病原线虫来自易感病杂草的富集作用。因此,三七育苗地的选择、育苗和移栽过程中杂草的清除是病害防控的关键。

[Purpose]In order to provide reference for comprehensive prevention of root-knot nematodes disease,the present study investigated and identified the pathogen species and sources of rootknot nematodes in the understory plantation and nursery in Lancang County of Yunnan Province.[Method]The systematic investigation method was used to investigate the occurrence of Panax notoginseng and weeds root-knot nematodes disease and identify the pathogenic nematodes of the P.notoginseng and the weeds which under the same habitats in the understory plantation and nursery in Lancang County.[Result]Among the three bases,the root-knot nematode of Datangzi nursery base was the most harmful,with an incidence rate as high as 66.82%;followed by the forest base,while the Haguoma nursery base was relatively light.After collection and identification,the pathogenic rootknot nematodes that endangered P.notoginseng and weeds in the forest base and nursery bases were Meloidogyne hapla.There are 97 species of weeds distributed under the Pinus kesiya var.langbianensis forest,among which two weeds with root-knot nematode disease include Ageratina adenophora and Centella asiatica.According to the distribution abundance of weeds and the parasitic degree of root knot nematode,A.adenophora is the main intermediate host of root knot nematode of P.notoginseng.The types of weeds in the two nursery bases are basically the same,with 124 species of weeds distributed,among which 11 weeds with root-knot nematode disease include Rabdosia serra,A.adenophora,Bidens pilosa,Laggera alata,Cassia nomame,Crassocephalum crepidioides,Elsholtzia ciliata,Emilia sonchifolia,Anemone rivularis and Siegesbeckia orientalis.According to the distribution abundance of weeds and the parasitic degree of root knot nematode,B.pilosa,C.crepidioides and A.adenophora are the main intermediate host of root knot nematode of P.notoginseng.[Conclusion]The pathogenic nematodes which infected P.notoginseng and weeds in the understory plantation and nursery in Lancang County were confirmed as M.hapla.The disease of seedlings is the main reason for the occurrence of root knot nematode of P.notoginseng in the forest,and the pathogenic nematode in the soil of nursery comes from the enrichment of susceptible weeds.Therefore,the selection of Sanqi nursery grounds,the removal of weeds during nursery and transplanting are the key to disease prevention and control.