Statistical modeling of insect behavioral response to changes in weather conditions in Brassica napus L

Understanding specific meteorological factors that affect the foraging activity of pollinator insects can provide valuable information to ensure appropriate levels of pollination of crops. This research was carried out to verify the spectrum of pollinating insects and their foraging behavior in relation to specific meteorological variables in the Brassica napus (rapeseed) crop. Data collected consisted of the following observations: number of visits by each pollinator, floral resources collected by Africanized honeybee Apis mellifera L., number of flowers visited by Africanized honeybees in 1 min, number of flowers visited by Africanized honeybees in one specific plant during the timed observation of 1 min, and the time taken by the honeybees to visit each flower. In this study the analyses were made through different generalized linear models. The Africanized honeybees were the most abundant pollinating insects (88%) and most visitors were observed collecting nectar (90%). The Africanized honeybees visited a total of 12.9 ± 1.40 flowers in 1 min and 2.96 ± 1.09 flowers of a single plant in 1 min. The time the honeybees spent on the rapeseed flowers was 4.2 ± 1.6 s. The number of floral visitors correlated closely to the variation of abiotic factors, especially temperature, relative humidity, wind speed, and solar radiation. Africanized honeybees were more active at different times of the day as compared to the other floral visitors and they foraged more intensely on the Hyola 433 hybrid than on the Hyola 61 hybrid. The Hyola 61 hybrid was more attractive to Diabrotica speciosa and Lepidoptera.