Quantification of consumption of corn pollen by the predator Coleomegilla maculata (Coleoptera: Coccinellidae) during anthesis in an Illinois cornfield
نویسندگان
چکیده
1 Coleomegilla maculata DeGeer feeds on corn pollen in the field, but the degree to which this predator relies on corn pollen as part of its diet is not well understood. We quantified the amount of pollen consumed by C. maculata second, third and fourth instars and adults in the field. 2 Laboratory experiments were conducted to determine the digestion rate and duration of different stadia or stages using temperature regimens that reflected field conditions during anthesis. Coleomegilla maculata larvae and adults were collected from the field and the amount of pollen in their digestive tracts was determined gravimetrically. The rate of digestion, duration of each life stage and the field observations were used to estimate the amount of pollen consumed by second, third and fourth instars and adults. 3 Our models estimate that larvae consume 0.66, 1.67 and 3.30mg of pollen during the second, third and fourth stadia, respectively. Adults consumed an estimated 13.15mg during anthesis. 4 The relevance of our results to ecological risk assessment of transgenic insecticidal corn and predator life history strategies is discussed. The results presented here are a first attempt to quantify pollen consumption by a predator, and future areas of research are suggested.
منابع مشابه
Abundance of Coleomegilla maculata (Coleoptera: Coccinellidae) in corn rootworm-resistant Cry3Bb1 maize.
Lady beetles (Coleoptera: Coccinellidae) are important polyphagous predators in maize, Zea mays L., fields. Transgenic Cry3Bb1 maize hybrids express a coleopteran-specific insecticidal protein derived from Bacillus thuringiensis (Berliner) subsp. kumamotoensis that is targeted at corn rootworm larvae. This study evaluated impacts of Cry3Bb1 protein-expressing maize, tefluthrin-treated maize, an...
متن کاملLarval feeding on Bt hybrid and non-Bt corn seedlings by Harmonia axyridis (Coleoptera: Coccinellidae) and Coleomegilla maculata (Coleoptera: Coccinellidae).
Zoophytophagy is an omnivorous activity that occurs when a primarily carnivorous species feeds on plant material. Plant feeding by beneficial predators may have negative consequences if the plant material has been chemically treated, contains toxins, or was transgenically altered. Although common in predaceous Hemiptera, zoophytophagy has been rarely studied in aphidophagous coccinellids. This ...
متن کاملBIOLOGICAL CONTROL Effects of Systemic Imidacloprid on Coleomegilla maculata (Coleoptera: Coccinellidae)
The coccinellid predator Coleomegilla maculata (DeGeer) is found throughout the central and eastern United States and is a potential biological control agent for interiorscapes. Currently, the systemic insecticide imidacloprid is widely used in interiorscape and landscape integrated pest management. Effects of imidacloprid on the Þtness and behavior of C. maculata were examined by conÞning grou...
متن کامل