Plant Parasitic Nematode Species And Community Structure Under The Rhizosphere Of Fruit Trees In Shanxi Province

Nematodes samples were collected under the rhizosphere of 10 kinds of fruit trees in 14 Counties,Shanxi Province from September 2016 to July 2018 and extracted using Whitehead method.Plant parasitic nematodes was then identified base on the morphological and molecular characteristics if available.In addition,the dynamic changes of nematodes population structure and quantity was analysed in the present study.The results are as following:1.10 species in 9 genera of plant parasitic nematodes were isolated and identified from the rhizosphere soil of fruit trees in Shanxi Province.They are: Tylenchida: Criconemoides sp.,Filenchus sp.,Helicotylenchus pseudorobustus(Steiner 1914)Golden 1956,Helicotylenchus digitiformis Ivanova,1967,Paratylenchus sp.,Tylenchorhynchus claytoni Steiner 1937,Tylenchulus semipenetrans Cobb 1913;Aphelenchida: Aphelenchus avenae Bastian 1865 and Dorylaimda: Longidorus pinus Xu,Ye,Wang & Zhao 2018 and Xiphinema brevicolle Lordello & Da Costa 1961.2.The nematodes community quantities under the rhizosphere of fruit trees were obviously different in orchards collected from four districts of Shanxi Province.The order of nematodes total quantity were Jincheng > Datong > Qixian> Yuncheng.The quantity order for nematode trophic groups were bacteriophagous nematodes > plant parasitic nematode >fungivorous nematode > predatory nematode,and bacteriophagous nematodes were the most largest population but there is less or no predatory nematodes.The quantity order for the plant parasitic nematodes were Jincheng City > Yuncheng City > Datong City > Qixian county.3.There were differences in nematode trophic groups and quantity under rhizosphere soil of Chinese jujube at different altitude.For the nematode trophic populations,predatory nematodes were found only in 1200 m altitude,but they are not found in 400~1000 m.Moreover,plant parasitic nematodes,fungivorous nematode and bacteriophagous nematodesare found in altitude 400~1200 m.4.The nematodes numbers were different at different depths in different seasons.Generally,the nematode numbers in Spring and Summer are larger than in Autumn and Winter.The number of nematodes is the much greater in 5cm depth and the nematodes numbers are decreased with the increase of soil depth.Further research should be taken based on more samples in the future.