Transcriptome Analysis of Nitrate Enhanced Tobacco Resistance to Aphid Infestation

Abstract

Tobacco is an economic crop that primarily relies on nitrate as its nitrogen source, and tobacco aphid is one of the significant pests that harm its growth. However, the impact of nitrate supply on the resistance of tobacco to aphids remains unclear. Present study investigated the effects of different concentrations of nitrate supply on the reproductive capacity of tobacco aphids, impact of aphid infestation on tobacco growth, secondary metabolic and transcription changes. The results indicated that aphids preferred tobacco treated with higher concentration of nitrate, showing greater reproductive capacity under high nitrate supply. Inoculating tobacco with aphids under different nitrate concentration increased the levels of soluble sugars, free amino acids, jasmonic acid, and salicylic acid in shoot of tobacco. Additionally, it was observed that the cell wall development of leaves from low nitrate supply was incomplete, and the lignin content was lower than normal nitrate supply, regardless of aphid inoculation. RNA-seq analysis revealed several genes related to the pathway of aphid damage in tobacco, as well as some transcription factors associated with insect resistance (such as bHLH, MYB, WRKY, etc.). Collectively, our findings not only shed light on the physiological and biochemical responses of tobacco plants to nitrate treatment, but also offer novel perspectives for optimizing tobacco cultivation practices and enhancing insect resistance.

Keywords: NO3-, Secondary metabolic, RNA-seq, Myzus persicae, Nicotiana tabacum