Periodic Reporting for period 1 - FAB (Functional Agricultural Biodiversity : Optimising ecosystem service provision via functional agricultural biodiversity)
Período documentado: 2019-09-01 hasta 2021-08-31
1. To determine the effect of floral cover on the provision of crops pest suppression (biological control).
2. To determine the effect of floral cover on the provision of pollination.
3. To determine potential synergistic or competitive relationships between key ecosystem service providing insects (biological control and pollination), resulting from specific floral mixes.
4. To propose composition matrices of Functional Agricultural Biodiversity and methods of management which can be applied in the field to maximise ecosystem service provision.
To further investigate potential competition between pollinators and biological control agents over floral resources, small-scale cage experiments were performed to investigate the effect of bee presence (Bombus terrestris) on the provision of biological control services of cereal aphid pests by Aphidius wasps. Cages were manipulated to vary the composition of winter flowering species available to the bees and parasitoids. Irrespective of floral mixture, the parasitism rate of aphids was lower in the presence of bees, suggesting the possibility of competitive interactions between parasitoids and bees over floral resources, although the result was not statistically significant. Furthermore, parasitism rate appeared higher in the presence of buckwheat (Fagopyrum esculentum), although the result was not statistically significant. Further work is thus required, although results hint at the potential for buckwheat to reduce competitive interactions between bees and parasitoids and, in doing so, enhance the natural biological control services provided by parasitoids.
Since many beneficial insects such as Aphidius parasitoids are becoming increasingly winter active as a consequence of warming winters, the project further investigated the potential for supplementary feeding of specific floral nectars to enhance the cold tolerance of parasitoid wasps. Preliminary results have suggested that supplementary feeding with faba bean (Vicia faba) nectar acts to increase the cold tolerance of Aphidius wasps. For this reason, the use of faba bean in winter flower strips and winter cover crops could aid the winter survival of this beneficial insect. Any measure to aid the winter survival of Aphidius wasps would act to boost the resultant spring population and thus contribute to enhancing the ecosystem service of biological control.