Submitted to: Journal of Insect Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/10/2008
Publication Date: 7/17/2009
Citation: Blanco, C.A., Portilla, M., Abel, C.A., Winters, H.E., Ford, R.L., Streett, D.A. 2009. Soybean Flour and Wheat Germ Proportions in Insect Artificial Diet and Their Effect on the Growth Rates of Heliothis virescens (F.) (Lepidoptera: Noctuidae). Journal of Insect Science. 9:52 Interpretive Summary: Insect artificial diets are an essential part of numerous research protocols. The original purpose of these diets was to optimally produce insects for research. These diets usually surpassed the insect’s minimum nutritional requirements. Such diets might not be adequate to evaluate subtle effects of certain treatments. A diet with a borderline nutritional profile might be more useful for this purpose Soybean (nutrisoy) flour and wheat germ are the two most important protein components of wheat germ-based insect artificial diets. The effect of the proportion of these two ingredients in a Noctuidae-specific diet was investigated utilizing Heliothis virescens (F.) to develop a suboptimal diet that would not affect insect growth and reproduction while allowing us to evaluate subtle negative treatment affects.
Technical Abstract: Soybean (nutrisoy) flour and wheat germ are the two most important protein components of wheat germ-based insect artificial diets. The effect of the proportion of these two ingredients in a Noctuidae-specific diet was investigated utilizing Heliothis virescens (F.) to develop a suboptimal diet that, without drastically affecting this insect’s growth and reproductive rates, might help us finding subtle negative when these moths mate. First generation net reproductive rate values per female (females/female) was significantly lower on diet containing 25% nutrisoy flour : 175% wheat germ proportion from the original diet formula. Second generation net reproductive rate, development time, percent female survivorship, fertility, intrinsic rate of increase (?), finite rate of increase and female longevity were significantly lower in the 25% nutrisoy flour : 175% and in the 50% nutrisoy : 150% wheat germ diet. Survival rate of immature to adult stage was 1% on 0% nutrisoy : 200% wheat germ diet in the initial, first generation. Interestingly, those females exposed to these suboptimal diets produced a significantly higher number of eggs but the survivorship of their larvae was significantly reduced. Modifications to the protein content ratio of the original wheat germ-based insect artificial formula can produce certain negative effects on the growth of tobacco budworm.