Effects of Soil Physical Factors on Egg Survival of the Bean Leaf Beetle, Cerotoma trifurcata (Forster) (Coleoptera: Chrysomelidae)1

Publisher Website
Google Scholar
Abstract
The effects of soil moisture, texture, and temperature on bean leaf beetle eggs of different stages were quantified. Hatch of bean leaf beetle eggs held in a loamy sand, a sandy clay loam, and an organic soil at a range of moistures decreased at both moisture extremes (very wet and very dry soil). The eggs were less sensitive after they had absorbed moisture, and hatch depended on critical moisture thresholds specific to each soil. Survival of newly laid and swollen eggs held in oven-dry soil at four temperatures (15, 20, 25, and 30°C) for different exposure durations decreased as exposure time increased. Egg development ceased while the eggs were held in the dry soil, so that there was a delay in egg developmental time corresponding to the exposure time. Egg survival also decreased as exposure duration in saturated soil increased. Survival was greatest and development was least inhibited in saturated, organic soil. Survival decreased with increasing soil temperature and depth. These differences suggest that aeration is a major factor affecting egg survival.

This publication has 0 references indexed in Scilit: