Impacts of Food Diversity on some Reproductive Attributes in the Gray Field Slug <i>Deroceras reticulatum</i> (Müller)

Abstract

Using a food choice design consisting of a single, double and multiple diets, impacts of three common vegetables viz. cabbage (CAB), lettuce (LET) and potato (POT) on some important reproductive attributes of the gray field slug Deroceras reticulatum (Müller) have been assessed. Although adult body weight was not affected by the diets, brood size was maximum in a double diet (CAB+POT), but multiple diets (CAB+LET+POT) did not enhance egg productivity. Both LET and POT had induced significantly greater number of eggs per day in comparison with CAB. Multiple diets resulted in significantly heavier eggs than the eggs from single or double diet regimes. Eggs laid on LET had the lowest and that on CAB+LET+POT had the highest developmental time but the hatch rate across the diet regimes did not differ significantly. Hatchlings from the single diet treatment were heavier than the double diet regime, but those between single vs. multiple or double vs. multiple diets did not vary statistically. The heaviest hatchlings were from LET and the lightest ones were from the CAB+LET treatments. The present results would help researchers in selecting a convenient culture medium for rearing experimental slugs in the laboratory. In addition, the data suggest that polyculture of vegetables might reduce slug damage, especially by reducing the brood size, egg production and hatchling size of D. reticulatum in the fields.

Key words: Deroceras, field slug, food diversity, reproductive attributes, alternative food source  

doi: 10.3329/jbs.v15i0.2198

J. bio-sci. 15: 15-21, 2007