Abstract:

In order to explore the impact of regional rice cropping structure changes on the occurrence of the population of Chilo suppressalis, the population of Chilo suppressalis under the lamp and rice crop data from 2013 to 2022 in Linhai City were analyzed. The results showed that with the decrease of the proportion of single-season rice planting area in the annual rice cropping structure, and the increase of the proportion of early rice and continuous late rice area, the rice cropping pattern was transitioned from single-season main planting mode to obvious single-double mixed planting mode, which led to the increase of the cumulative moth population of Chilo suppressalis throughout the year, and the main generation of adult insect pests moved from overwintering generation to second generation. The proportion of the overwintering generation of the moth in the annual moth volume was significantly negatively correlated with the proportion of the annual early rice area and the proportion of the annual continuous cropping late rice area, and was significantly positively correlated with the proportion of the annual single-cropping rice area. The proportion of the second-generation moth in the annual moth volume was significantly positively correlated with the proportion of early rice area and the proportion of late rice area under continuous cropping, and negatively correlated with the proportion of single-cropping rice area in the whole year. Rational adjustment of rice cropping structure in the region is an effective means to control the population of Chilo suppressalis and reduce its occurrence and damage.

Key words: rice, rice cropping structure, Chilo suppressalis, population