Bees Boost Canola Yields

SYDNEY - Mar 2/06 - SNS -- Australian researchers say using bees to pollinate canola fields can increase seed yields and oil content 20%.

Research officer Rob Manning said research at a site near Wongan Hills examined the benefits of placing hives of honeybees in canola at a density of about one hive per hectare. For the project, they placed three 100-hive apiaries in a crop of Karoo canola for a period of 51 days, or about 90% of the flowering period.

Using sample plots, plants were harvested, measured for height, number of branches, number of pods and total seed yield and oil content.

He said the research confirmed the use of honeybees increased seed yield and the benefits of honeybee pollination declined the further plants were from an apiary.

Further work confirmed that poorly pollinated plants channelled more resources into larger seeds, while plants benefiting from insect pollination produced more but smaller seeds.

"The benefits to growers of insect pollination come from higher yields through more pods per plant, more seeds per pod and higher rates of germinability of resultant seed," Manning said.

"In this experiment, yields of seed and oil increased by more than 20% or by 400 kilograms more seed and 150 kilograms more oil per hectare.

"There are several explanations for the increased yield including an enhanced production of fertile pods and thus more seed, particularly small seed."

Manning said the distance of plants from the apiary influenced the yield of pods with yield declining in plots located more than 200 meters from the apiary.

"In all cases there was no difference in yield between the 100 and 200 meter plots but yield dropped sharply at 300 meters before recovering somewhat at 400 meters," he said.