Effect of intercropping pepper with sugarcane on populations of Liriomyza huidobrensis (Diptera: Agromyzidae) and its parasitoids

The effect of intercropping pepper with sugarcane on populations of the leafminer Liriomyza huidobrensis Becker was investigated over two seasons (2007, 2008) in Yunnan, China. Populations of adults, the female:male sex ratios and the densities of larval mines were significantly higher in pepper monoculture than in intercropping in a 2:2 pattern (2 rows of pepper to 2 rows of sugarcane), which in turn were significantly higher than intercropping in a 1:2 pattern (1 row of pepper to 2 rows of sugarcane). The densities of the parasitoids of the leafminer were significantly higher in intercropping than in the pepper monoculture. The total parasitism rates were 71.6%, 22.5% and 5.9% in 2007, and 69.5%, 20.6% and 5.9% in 2008, in the 1:2, 2:2 and pepper monoculture, respectively. The lower densities of leafminer adults, the lower female:male sex ratio, and smaller numbers of larval mines in the intercropping systems were attributed to the intercropping pattern and the growth of pepper. These results indicate that intercropping is suitable for the control of L. huidobrensis on pepper plants. These results demonstrate the utility of intercropping of pepper with sugarcane in the management of L. huidobrensis.

Research highlights► Intercropping pepper with sugarcane increased the abundance and efficacy of natural enemies of the leafminer Liriomyza huidobrensis. ► The density of the parasitoids of the leafminers in intercropping was significantly higher than in pepper monoculture. ► The female:male sex ratio of the leafminer in pepper plants was significantly affected by intercropping pepper with sugarcane: It was significantly lower in intercropping than that in pepper monoculture. ► Intercropping pepper with sugarcane is a valuable approach for managing Liriomyza huidobrensis