Meeting Abstract
P2-142 - The effect of macronutrient consumption on reproductive performance in locusts Millerwise, SM*; Talal, S; Harrison, JF; Eapen, C; Cease, AJ; Arizona State Univeristy, Tempe, AZ; Arizona State Univeristy, Tempe, AZ; Arizona State Univeristy, Tempe, AZ; Arizona State Univeristy, Tempe, AZ; Arizona State Univeristy, Tempe, AZ smillerw@asu.edu
Understanding the ecological and evolutionary significance of nutritional variation depends on assessing the effects on fitness. A technical challenge to developing such understanding is that for many insects, including locusts, reproduction is currently not possible on artificial diets. We overcame this challenge by supplementing artificial diets with fresh romaine lettuce ( Lactuca sativa L.) that had had a minimal effect on the amount of macronutrients consumed. We reared groups of migratory locusts (Locusta migratoria) from 5th instar through adulthood on one of three artificial diets varying in protein (p):carbohydrate (c) ratios (14p:28c; 21p:21c; 35p:7c). In week-old adult females, we found no effect of diet on the number of developed ovarioles, suggesting that dietary macronutrient content at this stage does not affect the maximal capacity for reproduction. However, in the first two weeks of adulthood, the number of egg pods, as well as eggs within each egg pod, increased with dietary p:c. Locusts fed the higher carbohydrate (low p:c) diets also delayed oviposition by two days. Thus, at least for lab-reared L. migratoria, high protein:carbohydrate diets during the late juvenile/early adult stage enhanced reproduction. These findings contrast with field studies of several locusts species that have indicated preference and performance benefits to carbohydrate-biased diets. Possibly these lab vs. field differences are due to higher energy costs in the field, tradeoffs between reproduction and migration, changes in diet effects during ontogeny, or the specific fitness measures used in different studies. This work was supported by NSF # 1942054.