Transcriptome Analysis to Identify Resistance Genes Associated With Tomato Varieties in Response to MED Bemisia tabaci (Hemiptera: Aleyrodidae)

Abstract

Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a serious insect pest of tomato crops. Our previous study revealed that the tomato varieties JinLingHongYu and ShiTouDaFen are resistant and susceptible to MED B. tabaci, respectively. In this study, we focused on determining the transcriptional response of these two tomato varieties before and after infestation with B. tabaci using Illumina sequencing. A total of 629, 859, 512 clear reads were mapped to the tomato reference genome. According to the filtering threshold (log2 ratio ≥ 2, false discovery rate (FDR) ≤ 0.05), 727 differentially expressed genes (379 upregulated and 348 downregulated) were identified in the susceptible tomato variety before and after infestation, respectively, while 1060 (537 upregulated and 523 downregulated) were identified in the resistant tomato variety. The Unigenes might be involved in the tomato variety resistance genes to B. tabaci, such as receptor-like kinase, the cell-wall-modifying enzymes of the xyloglucan endotransglucosylase/hydrolase family, expansin, tryptophan-arginine tyrosine transcription factor, cytochrome P450, GDSL esterase/lipase, Nucleotide-binding adaptor shared by Apaf1, R proteins and CED-4 (NB-ARC) and F-box. To verify the results of the transcriptome analysis, 18 genes were randomly chosen and subjected to RT–qPCR. The RT–qPCR results were the same as those of the transcriptome analysis. The present results provide important information on B. tabaci resistance mechanisms in tomato varieties that will be useful for further studies of the molecular mechanisms of this resistance and for breeding new pest-resistant varieties.