PE0 31a: Tomato: Phase 2 of an investigation into poor pollination performance by the native bumblebee, Bombus terrestris audax
- In 2014, Natural England withdrew permission to use non-native bumblebees, Bombus terrestris terrestris (Btt), in unscreened glasshouses and tomato growers must now use the native sub-species, Bombus terrestris audax (Bta) to pollinate crops. As a consequence, many growers have suffered substantial financial losses due to poor fruit set (e.g. up to £50k per hectare reported).
- In 2017, the British Tomato Growers’ Association (TGA) conducted an AHDB-funded survey ([PE-031]) to determine the extent of the problem. The report highlighted several important areas for further investigation which triggered this study (Phase 2).
- Phase 2 investigated Bta colony activity in greenhouses and how environmental conditions, such as hive temperature, and pollen availability affect the foraging behaviour of Bta.
- The study found that of the 161 Bta colonies monitored across 12 production sites, 62% went into decline within 2 weeks of being placed in the tomato crop, increasing to 90% within 4 weeks. Manual recording showed that adult bees were active (exiting and entering the hive) over a 12 hour period with peak activity between 11:00 and 14:00 and the total activity (number of times bees exited and entered the hive) was considerably higher in hives kept outdoors compared to hives in greenhouses.
- The study also found that, although variable, peak pollen release occurred between 12:30 and 13:30 on average each day. High day temperatures (>29◦C) inhibit pollen production and pollen release and may affect pollen viability.
DownloadsPE 031a_G S Report_Final_2018 PE 031a_Report_Final_2018
About this project
Aim: To reduce financial losses resulting from production deficit, increased labour and excessive hive input caused by the enforced change to Bombus terrestris audax for pollination of UK tomato crops.
- To investigate Bta biology and behaviour under different environmental conditions with particular emphasis on synchrony between bumblebee foraging and optimum pollen flow.
- To investigate Bta colony life in commercial tomato crops and the impact this has on hive input schedules and frequency of hive deliveries.
- To investigate the influence of environmental conditions on flower quality and pollen flow in the small fruiting cultivars which now make up 76.9% of UK production.
- To transfer the results of these studies to the UK tomato industry.
- To determine the need for further studies to satisfy the overall aim of the project.