Populations of honeybees pollinating sunflower crops on the central Darling Downs, Queensland

Abstract

Populations of honeybees pollinating flowering sunflower heads in 42 fields on the central Darling Downs were recorded. Mean populations ranged from 21.9 to 171.2 bees per 100 flowering heads. A calculated maximum requirement for the region during fine weather amounted to 24 bees per 100 flowering heads. Populations were positively correlated with number of hives within 3 km of fields. In 18 fields with no hives within 3 km, mean populations (apparently from feral colonies) ranged from 21.9 to 130.9 bees per 100 flowering heads. These populations showed no significant correlation with area of crop in the range 2-95 ha. In another study on the central Darling Downs, seed set was not significantly correlated with number of hives within 3 km, indicating that feral bee populations were adequate for sunflower pollination.

Diversity, abundance and behaviour of diurnal insects on flowering capitula of commercial sunflower in the Transvaal

“…The conventional strip count method was followed, as described by Free (1964); Benedek et al (1972); Langridge & Goodman (1974); Radford et al (1979) and Parker (1981). Species diversity and abundance were determined for randomly-selected plant rows.…”

“…Although modem hybrid sunflower cultivars are bred to have a self-pollination efficiency of up to 50%, insects are internationally reported to be the primary cross-pollinators of sunflower: in the United States (McGregor, 1976;Hurd et al, 1980), eastern Europe (Benedek, Manninger & Nagy, 1972), India (Goyal & Atwal, 1973), Argentina (De Diez, 1979) and Australia (Langridge & Goodman, 1974;Radford, Rhodes & Nielsen, 1979). Pollinators listed by .these authors included not only beneficial insects such as honeybees and solitary bees, but also agricultural pests such as American bollworm (larvae and moths) and spotted maize beetles.…”

Pollination activity and behaviour of honeybees (Apis melliferaL.) in commercial sunflower in the Transvaal

“…Several accounts of honeybee activity in sunflower fields exist (Free, 1964;Langridge & Goodman, 1974;Radford, Rhodes & Nielson, 1979;Krause & Wilson, 1981;Parker, 1981). these authors found that honeybee activity revealed a pattern on a daily basis and with the ageing of the sunflower field.…”