Crosstalk between Nutrient Signalling Pathways and Immune Responses in Rice

Rice is a staple food for more than half of the global population. Rice production is, however, severely affected by biotic and abiotic stresses. Fertilisers and pesticides are widely used in rice farming to maintain optimal yield and to prevent losses caused by environmental stress. However, the indiscriminate use of agrochemicals has adverse effects on the environment and human health. Stress caused by nutrient excess or deficiency has an impact on plant disease resistance. The interference of plant responses induced by nutrient stress can result in a positive or negative impact on resistance to pathogen infection. In this review, we explore the effects of combined stresses in rice, focusing on nutrient stress, such as nitrogen and phosphorous supply, and infection by fungal pathogen Magnaporthe oryzae, the causal agent of rice blast disease. Crosstalk between nutrient stress-induced and pathogen-induced signalling pathways in rice is discussed, as well, with particular emphasis on regulatory microRNAs. Understanding the interconnected regulations between nutrient stress and disease resistance will lay a foundation for rationally optimising fertiliser and pesticide use in rice production.