RNA-Seq revealed that infection with white tip nematodes could downregulate rice photosynthetic genes.

Abstract

White-tip nematode, Aphelenchoides besseyi is a kind of widely distributed migratory parasitic nematode that can infect plant shoots. Transcriptome sequencing of plant parasitic nematodes and their host plants is helpful for understanding their interaction relationship. This study first reported expression patterns of defense-related genes in rice, and rice transcriptomes at different periods after infection with A. besseyi. The result showed that the defense response pathways of rice changed obviously in the early stage of A. besseyi infection, including upregulated salicylic acid and jasmonate pathways and a downregulated ethylene pathway. Transcriptome analysis results suggested that A. besseyi infection was associated with the downregulation of multiple genes related to photosynthesis with possible suppression of the photosynthetic activity. It suggested that the photosynthesis system of rice could be suppressed by infections of migratory nematodes, including A. besseyi and Hirschmanniella oryzae, but was stimulated by that of a sedentary nematode, Meloidogyne graminicola, by comparing our study with the reported transcriptome. OS09G0417800 (OsWRKY62) might play an important role in the interaction of migratory nematodes and rice. It also indicated that the infection strategy of both A. besseyi and the reported migratory nematode H. oryzae was similar to that of the fungal pathogen Magnaporthe grisea. These results provided an interesting starting point to elucidate the mechanism of the interaction between rice and A. besseyi, as well as the host and migratory plant nematodes.