Comparisons of pollinator efficacy using pollen received on stigmas can be refined by incorporating experimental dose-response relationships for pollen deposition and fruiting responses. A range of discrete pollen doses applied to cranberry stigmas resulted in decelerating curvilinear responses for fruiting, berry size, and seed set. Minimum thresholds and maximum asymptotes bounded reproductive responses to incremental stigmatic pollen loads. Four bee species were compared for their pollination efficacies on commercial cranberries, using counts of pollen received by stigmas during single bee visits to previously virgin flowers. Differences between these bee species were found to be exaggerated when raw pollen counts were used for comparison because foragers of some species often delivered pollen in excess of that needed to maximize fruit and seed production. Sixfold differences between species in mean pollen deposition translated into 1.5-2-fold differences in predicted cranberry fruit set and size. Implications for pollen tube competition and agricultural production are discussed.

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The pecan aphid predators, Chrysoperla rufilabris (Burmeister) (egg, larva, and adult); adult Hippodamia convergens (Guerin-Meneville); Cycloneda sanguinea (L.); OUa v-nigrum (Say); and pupae of the parasite, Aphelinus perpaUidus Gahan, were tested in the laboratory for mortality to registered commercial pesticides. Concentration-response lines were estimated for C. rufilabris larvae and adults. Only the half and full concentrations (recommended on label for pecan) were tested on the other species.Fungicides and acaricides caused <50% mortality to all the species, indicating compatibility of the predators and the parasite with chemicals used for disease and mite control. Endosulfan and phosalone were least toxic, but none of the insecticideswas safe for all of the speciestested. Pyrethroids were not toxic to larvae and adult C. rufilabris but or~anophosphates and carbamates were. We observed differences in response by the egg, larva, and adult C. rufilabris to fenvalerate, cypermethrin, phosalone, endosulfan, lindane and dicofol. Pyrethroids were toxic to O. v-nigrum but phosalone, methidathion, ethion, lindane, and malathion were not. Only lindane was not toxic to adult H. convergens. All chemicals tested caused >70% mortality to C. sanguinea. Phosalone, lindane, fIuvalinate, endosulfan, and azinphos-methyl were not toxic to A. perpaUidus. Results from this study provide information about the selectivity of pesticides for integration of biological and chemical controls for pecan aphids.