Alfalfa leafcutting bee

Johansen, C., Jaycox, E.R. and Hutt, R. (1963). The Effect of Pesticides on the Alfalfa Leafcutting Bee Megachile rotundata. Stations Circular 418, Washington Agricultural Experiment Stations, Institute of Agricultural Sciences, Washington State University, p. 12. 

Torchio, P.F. (1973). Relative toxicity of insecticides, to the honey bee, alkali bee and alfalfa leafcutting bee (Hymenoptera Apidae, Halictidae, Megachilidae). I. Kansas Entomol. Soc. 46, 446-453. 

Johansen, C. and Eves, J. (1967). Toxicity of Insecticides to the Alkali Bee and the Alfalfa Leafcutting Bee. Washington Agricultural Experiment Station, College of Agriculture, Washington State University, Circular 475. 

Waller, G.D. (1969). Susceptibility of an alfalfa leafcutting bee to residues of insecticides on foliage. J. Econ. Entomol. 62,189-192. 

George, D.A. and Rincker, C.M. (1985). Results and conclusions of using pesticides with the alfalfa leafcutting bee in the production of alfalfa seed. J. Agric. Entomol. 2, 93-91. 

Rincker, C.M. and George, D.A. (1985). Effect of pesticide residues in alfalfa pollen and nectar on the foraging and reproduction activities of alfalfa leafcutting bees Megachile rotundata. J. Appl. Seed Prod. 3, 33-37. 

Guirguis, G.N. and Brindley, W.A. (1975). Carbaryl penetration into and metabolism by alfalfa leafcutting bees, Megachile pacifica. J. Agric. Food Chem. 23,274-279. 

Guirguis, G.G. and Brindley, W.A. (1976). Effect of chlorcyclizine, amino-pyrine, or phenobarbital on carbaryl metabolism in alfalfa leafcutting bees. Environ. Entomol. 5, 590-594. 

Tralomethrin was tested for bee hazard in alfalfa fields pollinated by leafcutting bees and treated by airplane or helicopter. In a first test, the authors observed the fate of females nesting in shelters placed in separate plots of a large field, which received applications at different rates in the evening. In a second test they preferred to use separate fields to compare the effects of treatments. Evaluation of hazards were done by preapplication and post-application records of the number of active females per 5-second scan per nesting unit. This count was replicated 10 times. The number of females in 13 nest tunnels was also assessed (25 replications) at night before the application and 2 days after the application [28]. 

Through tests on paper it was possible to classify several pesticides used on blooming alfalfa, according to their hazards to male leafcutting bees. In... 

Acidified residues of trichlorfon were more efficient against pest insects. They were tested on alfalfa-treated leaves kept in Petri dishes and proved to be no more hazardous to leafcutting bees than the non-acidified compound. Conversely, mortality in honey bees was twice as much as that with... 

Table 7.4 Residues of naled and oxydemeton methyl recovered in alfalfa leaves, pollen, nectar and pollen ball of leafcutting bees (after George and Rincker, 1985) [54]...

Pollen ball samples were extracted from nests 5,10, and 27 days following sprays, for residue analysis. No residues of the pyrethroid could be detected and phosalone concentration decreased from 1 to O.lmg/kg within the 3-week sampling period. Larval mortality was very stable in the four cell samples collected when the larval development was completed before treatment 3.5 and 4.8 percent of larvae died in alphamethrin and phosalone samples versus 3.5 and 4.8 percent after treatment, respectively. No residues were detected in live larvae, which means that both molecules were metabolized [36]. Residues of deltamethrin were determined in leafcutting bee provisions collected in a field shelter placed in an alfalfa crop sprayed at the recommended rate. The maximum concentration was... 

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