Benefits of bees in cropping has grains industry abuzz
Author: Sharon Watt | Date: 23 Mar 2016
Insect pollinators such as bees increase the yield of canola and many pulse crops, underlining the importance of encouraging and protecting these pollinators within Australian farming systems.
That’s according to CSIRO researcher Saul Cunningham who says the true value of insect pollinators in terms of crop production is now starting to be fully appreciated.
Speaking at Grains Research and Development Corporation (GRDC) Grains Research Updates in the southern cropping region, Dr Cunningham said research around the world and in Australia is demonstrating the important role pollinators play in achieving maximum yield in many crops.
“Experiments commonly show that even self-fertile crops such as many brassica species, including canola, yield more when insects increase the rate of pollination,” Dr Cunningham said.
“There is certainly a yield and economic benefit to be gained from the use of bees. And studies show that it is best to have a combination of native bees and managed honey bees.”
Dr Cunningham said knowledge around how to manage pollination for greatest yield benefit had not kept pace with other advances in agronomy.
“As a result, we typically pay great attention to inputs such as water, fertiliser and pesticides, but usually have an ad hoc approach to pollination, even when growing crops known to benefit from insect pollination.”
Critical to supporting insect pollinators in agricultural landscapes is the cautious use of insecticides, according to Dr Cunningham.
“The risk of exposure to insecticides is one of the challenges for pollinators in agricultural environments,” Dr Cunningham said.
“Protecting pollinators in Australian agriculture begins with careful use of insecticides that stays within the registered uses determined by the regulators.
“Considering all pesticide use through an integrated pest management approach will help minimise the need for pesticides in many situations.”
Dr Cunningham said good communication between growers and local beekeepers could reduce the risk of harm to bees during periods of insecticide use, however, wild pollinators were more vulnerable because they live in the same area for their whole life cycle.
Public concern regarding the impact of neonicotinoid pesticides on bees has led to restrictions on their use in Europe, and other jurisdictions have debated similar actions.
Dr Cunningham said the Australian Pesticides and Veterinary Medicines Authority conducted a review of bee health in Australia in 2014 and concluded that there was no need to follow the European example by further restricting allowable uses of neonicotinoids.
“But we do need to learn more about field exposure of pollinators to insecticides to ensure that we can reduce conflicts and keep crop pollinators doing their good work.”
Dr Cunningham said that while neonicotinoids were known to be toxic to bees (like most insecticides), they could be applied in ways – such as seed treatments rather than foliar applications – that greatly reduced field exposure.
“Protecting pollinators is in the best interests of growers, but is also important because insect pollinators matter to neighbouring growers, to beekeepers and to the health of other vegetation in the landscape.”
To further encourage insect pollinators in the agricultural landscape, the retention and establishment of patches of non-cropped land is advised.
“Wild pollinators also need flowering resources to feed on and locations in which to nest, and so benefit when little patches of habitat are preserved throughout the farmed landscape, such as scattered trees, roadsides and fence lines,” Dr Cunningham said.
GRDC Southern Regional Panel member, Bill Long, concurred with Dr Cunningham’s viewpoints on the need to protect pollinators in cropping systems.
“We need to think more carefully about insecticide use and its impact on all insects which improve pollination in pulse and oilseed crops,” Mr Long said.
Mr Long, who is also a farmer and an agricultural consultant based at Ardrossan in South Australia, is particularly interested in the role of native honey bees in agricultural systems.
This interest won him a Churchill Fellowship in 2009, and he travelled to the United Kingdom, Europe and the United States to gain a better understanding of the impact of Varroa mite on honey bee numbers and its subsequent effects on crop pollination.
Varroa mite is an exotic deadly parasite of the European honey bee which has spread to all inhabited continents except Australia. The Varroa mite is considered the greatest challenge facing world beekeeping.
Saul Cunningham, CSIRO
0427 515 283
Sharon Watt, Porter Novelli
0409 675 100