Will genetically-engineered (GE) mustard, awaiting approval for mass cultivation, affect bee population and impact the production of honey? “I have seen the report,” replies R K Thakur, guardedly. “It says there is no reduction in nectaries or pollen content.” Thakur is coordinator for the national research project of the Indian Council of Agricultural Research on honey bees and pollinators.
“I have to protect the pollinators. That’s why I am here,” Thakur asserts. He will make an evaluation of GE mustard’s impact on pollinators once it is approved for commercial use. His position differs from the stand of the activists who want a ban on a presumption of adverse impact. Thakur does not want to extrapolate the experience of Canada, where GE rapeseed, a related species, was approved for cultivation in 1996 and no harm to honey bees has been reported. Canadian species and environmental conditions may not be comparable, he says.
The report which Thakur is referring to is a summary of the 3,285 page bio-safety dossier on GE mustard. A subcommittee of the Genetic Engineering Appraisal Committee (GEAC), the regulator for GE crops, had prepared it so the public could make informed comments. It says “…[E]xposure of honey bee to barnase and barstar proteins is highly unlikely and therefore risk to honey bee population due to cultivation of DMH 11 hybrid is considered negligible.”
Thakur has told honey exporters to “respect” the Delhi University scientists who have been working on improving Indian mustard for the past three decades. “We cannot say, ‘No, no it cannot happen’ by shouting slogans and politicking. We should respect the science. We must definitely have trials once the seeds are available to check if the concerns are are genuine or unfounded.”
Cotton is the only GE crop that is being cultivated in India. It contains the Bt protein derived from a soil bacterium. It is toxic to bollworms. The transgenes, barnase and barstar, used in GE mustard are different. They are not for crop protection but to create versatile hybrids of high purity for yield improvement.
Trials at Tamil Nadu Agriculture University (TNAU) in the winter of 2014 showed that bees thrived in Bt cotton fields. Insects play a vital role in the pollination of cotton. It was observed that honey bee colonies built up considerably during the flowering period. Populous colonies, of about 60,000 bees, are required for viable honey production. The life of a flower is up to 72 hours. Of this, the first 48 are the most productive for nectar secretion. A large foraging force will result in higher nectar collection. Broods will grow faster if there is enough nectar to provide energy and pollen for protein.
TNAU researchers observed that the brood area of honey bees was bigger in non-Bt fields in October but the situation reversed in the subsequent two months. Overall, during a three-month period, it was found that brood area in Bt fields was 948 square cm. This was 114 square cm more than in non-Bt fields, indicating that the pesticide-free environment of Bt cotton was conducive for honeybee growth.
Seed production of Bt cotton was higher in both open pollinated and bee- pollinated conditions. When pollination was prevented Bt cotton fields produced 1,379 kg of seed per hectare, compared to 1,190 kg in non-Bt fields. When only bees did the pollination, the output increased. It was 1,620 kg and 1,257 kg respectively. With open pollination, seed production rose to 1,904 kg in Bt cotton fields and 1,314 kg in non-Bt cotton fields.
Both cotton and mustard are good sources of nectar for bees. For commercial production of honey—40-60 kg per colony per year—the hives have to be migrated from place to place in quest of bee flowers. This is a seasonal exercise and is done by moving them around in trucks. Like nomadic cattle herders and shepherds, the bee-keepers live in tents next to their colonies.
By this time of the year, bee-keepers would have already colonies from Himachal Pradesh or from the plains to the mustard- growing regions to build up bee population. The summer heat would have made the colonies weak. In Himachal, they would have been under attack from predatory wasps. As the cold intensifies and mustard blooms, honey extraction will commence in Haryana and Rajasthan. The bee-keepers will then go on to Punjab, where they will extract honey from berseem fodder plants and eucalyptus, though highway expansion has reduced the number of trees bees can forage on.
Bee-keeping can profitably engage a large number of people. Besides creating income, pollination is very essential for yield improvement and quality enhancement. Apple-growers have been persuaded about the benefits of bee pollination, says Thakur. Through managed pollination—the use of pollen diffusers or devices with hand-collected pollen though which bees are made to pass—fruit quality improves. All the five apple lobes get fully developed. The fruit is well-formed and acquires a nice color. Growers pay more than R1,000 per colony, per season, says Thakur.
It has been estimated that bee pollination can increase the production of almond, guava, litchi, and amla by 20%, that of apples by 24-40%, of peaches and pears by 50%, bananas by 63% and mangoes by 68%. The number of bee colonies recommended per hectare ranges from four for apple and pear, to five for watermelons and eight for strawberries. Oilseeds sunflower, safflower, rapeseed and niger depend entirely on honey bees for pollination. Ninety percent of the crops are cross-pollinated, and most of them depend on insects for the purpose. The loss of bee habitat and increased use of pesticides is detrimental to the long-term sustainability of agriculture. Globally, pollination is estimated to be worth $224 billion a year, says Thakur.
Vegetable cultivation in climate-controlled conditions is on the rise, but greenhouses deter pollination because honeybees shy away from confined spaces. Bumble bees are an alternative. Thakur has done pioneering work in the area. Unlike honeybees, they are buzz pollinators. Their vibrations cause anthesis or the opening of anthers for pollen release in crops like tomato and capsicum. The rearing of stingless bees is another promising area. This activity is prevalent in Kerala and the North-east. Their honey sells for as much at R3,000 a kg at the farm gate for medicinal reasons.
In the US, president Barack Obama has made the survival and health of pollinators his concern. In June, he announced a Pollinator Partnership Action Plan. “Pollinators are responsible for one in every three bites of food we take, with honey bees alone increasing our nation’s crop values by more than $15 billion each year,” the White House website says. Since many pollinators are in decline in the US and worldwide, president Obama issued a presidential memorandum establishing the Pollinator Health Task Force in June 2014. Much good can come out of the anti-GE mustard protests if the protection of pollinators becomes a national priority in India as well.
The author is editor of www.smartindianagricuture.in, a website devoted to promoting modern practices in agriculture, including use of genetically-engineered seeds.