Responses Of Rice To The Interactions Between Heterodera Elachista And Meloidogyne Graminicola

Heterodera elachista and Meloidogyne graminicola are important pathogenic nematodes in rice production.In recent years,these two nematode diseases have occurred frequently in rice production areas in southern my country,seriously threatening the safety of rice production.Because the two nematodes have similar niche,interspecies interaction and rice response to nematode interaction may be important factors affecting their outbreak.By comparing the effects of the interaction between two nematodes on population development and host selectivity,the paper initially clarified the interaction mechanism between two nematodes;by detecting Heterodera elachista,Meloidogyne graminicola and their mixed infections,the roots and leaves of wood The changes of the content of selenium,soluble phenol,hydrogen peroxide and malondialdehyde explored the effect of the interaction of the two nematodes on the physiological and biochemical characteristics of rice;using fluorescence quantitative PCR to analyze the genes related to defense response of Heterodera elachista,Meloidogyne graminicola and their mixed infections in rice Differential expression explores the molecular response mechanism of rice to two nematode species.Effects of Heterodera elachista and Meloidogyne graminicola on nematode-infected and non-infected rice host selection and nematode growth and development: At a certain population density,Meloidogyne graminicola infects rice for 2 days,which will interfere with Heterodera elachista’s selection of host rice plants,and Meloidogyne graminicola on host rice plants The choice is not affected by Heterodera elachista;meanwhile,the parasitism of Meloidogyne graminicola can delay the growth and development of Heterodera elachista,but the two nematodes can coexist in the rice root system.Effects of interspecific interactions between Heterodera elachista and Meloidogyne graminicola on the physiological and biochemical properties of host rice plants: The content of related secondary metabolites in rice was determined.The results showed that compared with the control,Heterodera elachista and Meloidogyne graminicola infected rice woody The accumulation of element,soluble phenol,hydrogen peroxide and malondialdehyde all increased to varying degrees.After 30 days of infection with Heterodera elachista,the content of lignin and malondialdehyde in rice roots increased significantly;the content of lignin,soluble phenol,hydrogen peroxide and malondialdehyde in rice tissues infected with Meloidogyne graminicola increased significantly;The accumulation of lignin in rice tissues increased significantly,while the content of soluble phenols increased significantly in rice leaves.The remaining substances did not change significantly.The harm of Meloidogyne graminicola induced the changes of more secondary metabolites in rice,such as the significant increase of soluble phenol and hydrogen peroxide,which may be an important factor that Meloidogyne graminicola interferes with Heterodera elachista.Interaction between Heterodera elachista and Meloidogyne graminicola on the expression of host defense-related genes: Fluorescence quantitative PCR analysis of related defense genes in rice roots and leaves revealed that rice was produced after mixed infection by Heterodera elachista,Meloidogyne graminicola and two nematodes The defensive molecular mechanism is similar.After 4 days of nematode infection,the expression of genes related to salicylic acid and jasmonic acid signaling molecules(Os NPR1,Os PR1 b,Os Ja MYB)in rice roots was down-regulated,while common defense-related genes(Os C4 H,Os CAD,Os GSL1,Os GSL5,PR-1a,PR-10,Os WRKY53,Os MAPK6)up-regulated expression;10 days after inoculation,the expression of most common defense-related genes was down-regulated.The gene response in rice leaves and roots is quite different,such as Os Rboh B,Os MAPK6,Os C4 H,Os GSL1,Os PR1 b,etc.,the expression of in rice roots and leaves showed a reverse trend.