I think this study has significance beyond telling us something we already know... or more to point, telling something people farming canola think they know. There has been a significant shift in canola cropping systems since a lot of the canola pollination work was last done. The canola industry still operates under the paradigm of these studies - ie Brassica napus does not benefit from supplemental honey bee pollination. This study suggests there may be need to revise this paradigm now that they largely farm GM. The paper describes a significant pollination deficit in Round-Up Ready fields arising from fewer pollinators (~1.5 times greater yield compared to a coventional field and ~6 times greater compared to an organic field). What does a ‘pollination deficit’ mean in the context of this study? It means a difference in the average number of seeds per fruit between supplementally pollinated (what would happen if you had unlimited pollinators) and open-pollinated flowers. Overall GM seedpods had around 6 fewer seeds per seedpod when open-pollinated compared to being supplementally pollinated, whereas in organic fields the difference was just 1 seed per seedpod. Clearly the GM fields would benefit from having more pollinators. I am not sure GM canola, as a rule, run pollination deficits compared to conventionally grown canola... this requires additional study. If it turned out to be true, might it not offer beekeepers an opportunity to revaluate their relationships with their canola-growing neighbours? Currently Canadian beekeepers are not paid to put bees on production canola fields, only in the fields used to produce hybrid seed for planting. A persistent pollination deficit in GM fields would no doubt be a potential boon for beekeeping. Rather than write the study off as being common sense, I think it should be repeated. I think this was a nicely-done study. It was conscice, well executed and conducted one of Canada's most significant crops (argueably the most imporant honey bee forage). I agree with Peter and Allen that it was a shame that it got yanked out of context and used to make the case for GM crops repelling bees from fields. This careless arguement distracted from the very carefully laid and supportable case that the yield increases from Round-Up Ready canola cropping systems may be subverted by their inability to sustain large populations of pollinators. For anyone who is still interested (and I doubt there are many) I have attached a summary of the state of knowledge on this issue as of 2001 from a Bee World review by Don Nelson and Lynn Westcott (sorry for the spaces). In the Morandin study, the organic field was B. rapa (ie the self-sterile cultivar) whereas the conventional and GM fields were B. napus (ie self-pollinating). Regards, Adony The need for insect pollinators in canola and rapeseed crops. It is generally considered that cultivars of B. rapa are self-sterile and require insect crosspollination to set seed11,19,28,42,92, but there are conflicting views on the need for insect pollination in B. napus. Brassica napus is considered self-fertile and produces good seed yields without insect pollination19,23,92. Despite their assertions that insect pollinators are not necessary for good seed yield in B. napus, Free & Nuttall reported a 13% seed yield increase in B. napus plots with bees compared to those without bees23. They did not feel that this was a large enough increase to justify the use of bees for pollination23. Downey et al. reported that B. napus is 70% self-pollinated, but this presumably leaves the remainder in need of insect- or wind-mediated cross-pollination19. Canola and rapeseed have sticky pollen typical of plants requiring insect pollination20, which suggests that wind activity is not the only means of B. napus pollination. Windpollinated species usually have smooth, dry pollen grains that are readily dispersed through the air. Eisikowitch found that B. napus cv. Maris Haplona pollen adhered to the flowers’ anthers under wind velocities as high as 5.0 m/sec20. He suggested that selfpollination must be the result of direct contact between the long anthers and the stigma with little pollen transfer through the air20. He concluded that insect pollination is important in setting seeds in this particular B. napus cultivar. Many researchers have concluded that insect pollination of B. rapa and B. napus is necessary to provide high seed-meal lipid concentration78, higher seed set and yield43,45,58,78, higher numbers of seeds per pod and higher numbers of pods41,92, earlier pod formation21,96, earlier cessation of flowering 58,96, faster and more uniform seed maturation 46, and increased germination of seeds39. All of these factors may contribute to a higher-quality crop that ripens more evenly and is easier to harvest95. Most of the canola hybrids and open-pollinated cultivars currently produced and sold to Canadian growers are B. napus. Farmers who purchase and grow these hybrids may be interested to understand the pollination requirements of their crop, especially if B. rapa hybrids are developed and become commercially available within the first decade of the 21st century50. Canola growers may find it beneficial to work co-operatively with beekeepers to maximize their seed yield. ****************************************************** * Full guidelines for BEE-L posting are at: * * http://www.honeybeeworld.com/bee-l/guidelines.htm * ******************************************************