Ojeda-Avila T, Woods H Arthur, Raguso R A
Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA.
J Insect Physiol. 2003 Apr;49(4):293-306. doi: 10.1016/s0022-1910(03)00003-9.
Most studies linking dietary variation with insect fitness focus on a single dietary component and late larval growth. We examined the effects of variation in multiple dietary factors over most life stages of the sphingid moth, Manduca sexta. Larvae received artificial diets in which protein, sucrose, and water content were varied. The relationship between larval size, growth and consumption rates differed significantly across diets. Larvae on control and low-sucrose diets grew most rapidly and attained the largest pupal and adult sizes. Conversely, larvae on low-water and low-protein diets initially grew slowly, but accelerated in the fifth instar and became pupae and adults comparable to control animals in size. There were no fundamental differences in protein:carbohydrate consumption patterns or strategies among experimental diets and larval instars. However, inadequate dietary water appeared to be more important for early than late instar larvae. Larvae on all artificial diets showed increasing fat content throughout all stages, including wandering and metamorphosis. Compensatory feeding among low-water and low-protein larvae was correlated with significantly higher fat content in larvae, pupae and adults, whereas low-sucrose animals were substantially leaner than those on the control diet. These differences may have strong effects on adult physiology, reproduction, and foraging patterns.
大多数将饮食变化与昆虫健康状况联系起来的研究都集中在单一饮食成分和幼虫后期生长上。我们研究了多种饮食因素的变化对天蛾科昆虫烟草天蛾大部分生命阶段的影响。幼虫食用蛋白质、蔗糖和水分含量不同的人工饲料。不同饲料下幼虫大小、生长速度和摄食率之间的关系存在显著差异。对照组和低蔗糖饲料组的幼虫生长最快，化蛹和羽化后的体型最大。相反，低水分和低蛋白饲料组的幼虫最初生长缓慢，但在五龄期加速生长，化蛹和羽化后的体型与对照组相当。不同实验饲料和幼虫龄期之间，蛋白质与碳水化合物的消耗模式或策略没有根本差异。然而，对于低龄幼虫来说，饮食水分不足似乎比高龄幼虫更为重要。所有人工饲料喂养的幼虫在包括预蛹期和变态期在内的所有阶段脂肪含量都在增加。低水分和低蛋白饲料组的幼虫进行补偿性摄食，其幼虫、蛹和成虫的脂肪含量显著更高，而低蔗糖饲料组的动物比对照组的动物瘦得多。这些差异可能对成虫的生理、繁殖和觅食模式产生重大影响。
