Rice Mediated Interactions Between Rice Blast Fungus And Brown Plant Hopper

Rice blast fungus (Magnaport heoryzae, RBF) is a major rice disease and rice brown plant hopper (Nilaparvata lugens, BPH) is a major rice insect pest in China. Rice-mediated interaction between BPH and RBF was explored in this study using five varieties of rice (TeYou627, Jiahe B, Jinliangyou33, JinYou9 and T55You627) with different resistance characteristics. First, the rice-mediated effects of BPH on the number of lesions caused by RBF were studied. Then, the rice-mediated effects of RBF on the fecundity, egg hatching and feeding selectivity of BPH were examined.The experiments of rice-mediated effects of BPH on rice blast fungus showed that there were less blast lesions in 5 rice varieties treated with BPH compared with their control groups. Mechanical damage of rice punctured by the needle also caused less blast lesions, but with more blast lesions than BPH treatment. Thus, this suggested that the induced resistance by BPH feeding was not only caused by simple physical damage. In addition, the induced resistances by penetration were related to rice resistance against RBF.The experiments of rice-mediated effects of RBF on BPH showed that BPH feeding on plants with RBF infection produced less eggs and less eggs hatched compared with BPH feeding on control plants. Among 5 varieties, JinYou9 had the most dramatic declining effects on eggs produced and eggs hatched. As to the hatchability of eggs, infected rice of Jinliangyou33 had a remarkably decreased effect on BPH. It was concluded that BPH fecundity and hatchability in different varieties had no significant correlation with the plant resistance against BPH and RBF.In the study of BPH feeding selectivity on the rice with RBF infection and healthy rice, BPHs preferred healthy plants of Jinliangyou33 and JinYou9 and there were no significant differences observed for the other 3 varieties. It indicated that the presence of RBF had a certain impact on BHP feeding selectivity.