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SUSTAINABILITY I Jesus College Annual Report 2022
Improving pollinating plants to feed the world Hamish Symington A PhD student in Plant Sciences explains how research into insect pollination can improve food production
Six years ago, I gave up my job as a software developer, with the aim of returning to science and researching something that might leave the world a slightly better place for my daughter. Five years’ experience in beekeeping had given me a deep interest in bees and flowers, and I was fortunate to gain a PhD place funded by Biotechnology and Biological Sciences Research Council (BBSRC) looking at improving pollination of crops in the Department of Plant Sciences. A rising global population will need more food, and about a third of our crops by volume depend on insect pollination to some extent – but, around the world, insects are generally in decline. How do we reconcile that conflict? Alongside options such as reversing insect decline or breeding crop varieties which rely less on pollination, might it be possible to make it easier for insects to find flowers (meaning the same number of insects could visit more flowers per day), or to improve the nectar and pollen reward that those
flowers offer (giving insects more energy to take back to their nests)? Selection for improvement in these traits could then be included in breeding programmes, without any need for GM techniques. I set out to tackle these approaches in strawberry plants, for which fruit quality is improved by insect pollination. To see if I could make it easier for insects to find flowers, I focussed on petal shape, which is known to be involved in how insects perceive flowers. The approach I took was to characterise variation which already exists between different varieties, then use that information to test bee responses to the extremes of variation. A friendly strawberry farmer in Norfolk gave me access to a field where he grows 20 different varieties, and I spent several months photographing flowers and measuring them on a computer. This enabled me to make plastic flower models with which I could ask bees questions. Testing how fast bees can find flowers involves training laboratory-reared bees (who’ve never seen a flower) to visit the plastic flowers and giving them a small sugar-water reward each time. With plastic flowers at known distances apart, I can then time individual bees’ flights between them; if one flower shape is easier to find than another, then the bees will fly between them faster. Similarly, we can test if bees have an innate preference for flower shape by releasing a bee in a flight arena in which are flowers of both shapes, each containing a sugar-water reward, and watching which
