Dry And Wet Seasons Do Not Affect The Mortality Caused By Ants To Larvae Of Ascia Monuste Orseis (Lepidoptera: Pieridae)

Predatory ants are crucial biological control agents in agroecosystems, but such activity may vary during dry and wet seasons. In this study, we investigated whether the mortality caused by predatory ants to the larvae of Ascia monuste orseis (Godart) varies due to the effects of dry and wet seasons. We performed a field experiment repeated eight times for two years. In each period, we established a cabbage plot containing 40 plants and inserted another ten plants containing 45 +/- 13 (mean +/- standard deviation) larvae to estimate the mortality rates. We monitored ant predation by direct observations performed twice a day (08:00-10:00 and 15:00-17:00). During the experiment, the average daily temperature varied significantly (from 13 degrees C to 27 degrees C) with higher values during wet seasons, while for precipitation and relative humidity, we found significant variation only in the second year. Despite this, the mortality caused by ants did not vary between seasons in the same year. Mortalities (mean) were estimated at 13.81% (dry season, year 1), 10.45% (wet season, year 1), 23.47% (dry season, year 2), and 23.29% (wet season, year 2). Ants were found to belong to the genus Ectatomma, Camponotus, Pheidole, Pseudomyrmex, Solenopsis, and Tetramorium. Thus, our study indicates that predatory ants may be present year-round on Brassica crops, contributing to the biological control of A. monuste orseis.