Wild bees key to boost quality blackcurrant yields
Trials by scientists at East Malling Research (EMR) have revealed that wild solitary bees and bumblebees are key to high yield blackcurrant harvests and larger more uniform berry size. This was found to be especially important in bad weather.
Honeybees, however, were not found pollinating flowers on the nine plantations surveyed, and so play little part in the contribution to blackcurrant pollination.
The results are clear, said Dr Fountain. With just our wild bees, we achieved maximum pollination in warm, sunny weather on our Ben Gairn trials.
In the year of the trial, Ben Hope flowered later, during a period of poor weather with low temperatures and between 10 and 15mm of rainfall. The fruit set of the blackcurrant was up to 40 per cent lower in the open pollinated bushes compared to those which were supplemented with bumblebee nest boxes.
This is because the poor weather made wild bees less active.
The study has so far identified 13 species of bee foraging for pollen and nectar on blackcurrant.
Dr Fountain is now keen to see guidelines drawn up to assist blackcurrant and other fruit growers to maximise pollination levels by developing good local habitats for previously underrated wild bees.
Good management of local biodiversity and the wider environment plus considered use of pesticides could make all the difference to pollination levels and the quality of harvests.
Good pollination leads to well-formed, high quality fruit which must be every growers aim, she said.
EMR advice includes careful use of insecticides, especially around the time of flowering when native wild bees may be foraging within the crop.
Other crop management techniques suggested include ensuring native bees have access to the different environments they need for nesting, raising their broods and overwintering; encouraging a wide range of wild flowers and plants on field margins; mowing flowering alleyways before applying insecticides to avoid spraying foraging bees; and nurturing sustainable hedgerows to encourage biodiversity.
The blackcurrant trials, funded by Defra, GlaxoSmithKline and other industrial partners, have told us a great deal about pollination. However, they have also opened up new areas of scientific challenge which we are keen to pursue to provide our fruit growers with even more information to ensure maximum pollination and quality of their crops, said Dr Fountain.
East Malling Research
EMR is the principal UK provider of top-class basic, strategic and applied horticultural research
EMR scientists integrate their knowledge of breeding, molecular genetics, genomics, pest and disease biology and management, crop and post harvest physiology, agronomy, environmental science, food product development and consumer research, to address current industry issues and deliver innovative solutions
EMR customers include: Department for Environment, Food and Rural Affairs, commercial companies, EU, retailers, growers, levy bodies and Research Councils (EMR is affiliated to the Biotechnology and Biological Sciences Research Council)
EMR is currently engaged in eight HORTLINK projects including integrated pest and disease management, optimising water use and using plants as soil biomfumigants
For further information about EMR visit www.eastmallingresearch.com