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United States Department of Agriculture

Agricultural Research Service

Research Project: BIOLOGICAL CONTROL OF INVASIVE AND EXOTIC PESTS Title: Supplemental diets containing yeast, sucrose, and soy powder enhance the survivorship, growth, and development of prey-limited cursorial spiders

Authors
item Patt, Joseph
item Pfannenstiel, Robert
item Meikle, William
item Adamczyk, John

Submitted to: Biological Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 30, 2011
Publication Date: N/A

Interpretive Summary: We examined the effects of a food spray mixture called ‘wheast’) and its individual ingredients (sucrose, yeast, and toasted soy flour) on the survivorship, growth, and development of a cursorial spider, Hibana futilis Banks (Anyphaenidae). Some treatments included eggs of Helicoverpa zea, a favored prey, in limited quantities to mimic prey limitation in a field setting and highlight the relative nutritional contributions of the non-prey ingredients. Using prey-limited spiders was also useful for determining whether these spiders could be reared on a diet of minimal prey augmented with non-prey food. Spiders fed either 5 or 15 eggs became prey limited after their first and second molts, respectively. Spiders fed either only sucrose or only wheast lived as first instar nymphs for weeks, but while sugar-fed nymphs never molted; those fed wheast typically molted two to three times. When wheast was added to the diet, spiders that had fed on as few as 50 eggs could reproduce successfully. Binary mixtures of sucrose plus either baker’s yeast (Saccharomyces cerevisiae Meyen ex E.C. Hansen) or toasted soy flour were more effective in promoting growth and development in prey limited spiders than any of the three ingredients alone. Active baker’s yeast was more effective than dried powdered brewer’s yeast. These results demonstrate that the concept of using food sprays to promote cursorial spider conservation in cropping systems is feasible. They also suggest the possibility of devising mass rearing diets comprised of minimal amounts of prey combined with two or three inexpensive, non-prey food ingredients.

Technical Abstract: We examined the effects of a food spray mixture (‘wheast’) and its individual ingredients (sucrose, yeast, and toasted soy flour) on the survivorship, growth, and development of a cursorial spider, Hibana futilis Banks (Anyphaenidae). Some treatments included eggs of Helicoverpa zea, a favored prey, in limited quantities to mimic prey limitation in a field setting and highlight the relative nutritional contributions of the non-prey ingredients. Using prey-limited spiders was also useful for determining whether these spiders could be reared on a diet of minimal prey augmented with non-prey food. Spiders fed either 5 or 15 eggs became prey limited after their first and second molts, respectively. Spiders fed either only sucrose or only wheast lived as first instar nymphs for weeks, but while sugar-fed nymphs never molted; those fed wheast typically molted two to three times. When wheast was added to the diet, spiders that had fed on as few as 50 eggs could reproduce successfully. Binary mixtures of sucrose plus either baker’s yeast (Saccharomyces cerevisiae Meyen ex E.C. Hansen) or toasted soy flour were more effective in promoting growth and development in prey limited spiders than any of the three ingredients alone. Active baker’s yeast was more effective than dried powdered brewer’s yeast. These results demonstrate that the concept of using food sprays to promote cursorial spider conservation in cropping systems is feasible. They also suggest the possibility of devising mass rearing diets comprised of minimal amounts of prey combined with two or three inexpensive, non-prey food ingredients.

Last Modified: 10/20/2014