Species Identification And Community Diversity Analysis Of Plant Parasitic Nematodes In Rhizospheres Of Pyrus Sinkiangensi And Ficus Carica In Xinjiang

As an important class of plant pathogenic organisms,plant parasitic nematodes can infest the roots of fruit trees,causing dwarf plants,greenish mottled leaves,gradual decline in growth and even plant death in severe cases,which is an important factor affecting fruit quality and yield.From 2020 to 2021,62 inter-root soil samples of Pyrus sinkiangensi and 63 inter-root soil samples of Ficus carica were collected from different regions of Xinjiang,and nematodes were isolated from them,and the species identification of plant-parasitic nematodes in the soil samples was carried out based on the morphological and molecular characteristics of nematodes,and the population structure and diversity of nematodes were analyzed.The following results were obtained:(1)10 species of plant parasitic nematodes were isolated and identified from the inter-root soil samples of Xinjiang Pyrus sinkiangensi,belonging to 2 orders and 8 families and 9 genera,among which,Order Rhabditida has 7 families and 8 genera and 9 species,namely: Criconematidae,Criconemoides,Criconemoides informis;Hoplolaimidae,Helicotylenchus,Helicotylenchus digonicus 、 Helicotylenchus dihystera;Hoplolaimidae,Rotylenchus,Rotylenchus rhomboides;Pratylenchidae,Pratylenchus,Pratylenchus neglectus;Tylenchinae,Filenchus,Filenchus vulgaris;Aphelenchidae,Aphelenchus,Aphelenchus avenae;Aphelenchoididae,Robustodorus,Robustodorus subtenuis(homotypic synonym:Aphelenchoides subtenuis);Meloidogyninae,Meloidogyne,Meloidogyne incognita;Order Dorylaimida has one family,one genus and one species: Longidoridae,Xiphidorus,Xiphinema brevicollum.(2)8 species of plant parasitic nematodes were identified from inter-root soil samples of Ficus carica in Xinjiang,all belonging to Rhabditida,in five families and five genera,as follows: Rhabditida,Hoplolaimidae,Helicotylenchus,Helicotylenchus dihystera;Belonolainidae,Geocenamus,Meloidogyne brevidens;Tylenchinae,Filenchus,Filenchus vulgaris;Aphelenchidae,Aphelenchus,Aphelenchus avenae;Meloidogyninae,Meloidogyne,Meloidogyne incognita 、 Meloidogyne hapla、 Meloidogyne javanica、Meloidogyne floridensis.(3)The diversity of soil plant parasitic nematodes communities among Pyrus sinkiangensi roots varied in different regions of Xinjiang.In Pyrus sinkiangensi roots,Aphelenchus sp.was the dominant genus,Aphelenchus avenae was the dominant species;Filenchus sp.,Helicotylenchus sp.and Robustodorus sp.are common genera,and Pratylenchus sp.,Meloidogyne sp.,Rotylenchus sp.,Criconemoides sp.and Xiphidorus sp.are rare genera.The results of nematode community diversity analysis of inter-root soil of Pyrus sinkiangensi in different regions of Xinjiang showed that both H’ and J’were the highest in the inter-root soil of Pyrus sinkiangensi in Kulle city,with 3.11 and 1.93;SR was relatively high in the inter-root soil of Pyrus sinkiangensi in Luntai and Wensu counties,with 0.72,0.71;the inter-root PPI of Pyrus sinkiangensi in Rotai County was the highest at 0.96.(4)The diversity of soil plant parasitic nematodes communities in the inter-rhizosphere of Ficus carica also varies in different regions of Xinjiang,with Aphelenchus sp.being the dominant genus,Aphelenchus avenae being the dominant species,Filenchus sp.,Helicotylenchus sp.and the rare genus Geocenamus sp..The results of nematode community diversity analysis of Ficus carica inter-root soil in different regions of Xinjiang showed that J’ was the highest in the inter-root soil of Ficus carica in Shule County with 1.90;SR was relatively high in the inter-root soil of Ficus carica in Wensu County and Luopu County with 0.73 and 0.60;the inter-root soil of Ficus carica in Atushi City and Kuche County with H’ and PPI were relatively high,2.39,2.38 and 0.79,0.78,respectively.The results of the study clarify the species and distribution of inter-root plant parasitic nematodes of Pyrus sinkiangensi and Ficus carica,which provide a theoretical basis for studying the damage and risk assessment of two fruit tree nematode diseases and their disease control.