Assam Farmers Learn Organic Lessons From a Lab

By Samudra Gupta Kashyap

Farmers in Assam, especially those in districts close to the state capital, have found a new and safer method of pest control. The State Bio-Control Laboratory (SBCL) of the state agriculture department has isolated two exotic species of farmer-friendly insect bio-agents and have begun sharing these with farmers.

The two species of insect bio-agents — Trichogramma japonicum and Trichogramma chillonis — have earned considerable popularity among farmers, with the authorities claiming that they have not been able to meet the increasing demand.

“Our focus has been on paddy, brinjal, tomato, potato, chilli and sugarcane, and farmers have already started accruing a lot of benefit from these bio-agents,” said G C Borthakur, senior agricultural development officer at the SBCL.

“Farmers have realized that prolonged use of chemical fertilizers and pesticides have not only lowered soil quality but have also contributed towards pollution of both air and water. Thus, finding an alternative, more farmers are using our bio-agents.”

In Assam, a common pest affecting paddy is Scirpophaga incertulas, popularly known as stem-borer or moja-khowa in Assamese. “Over 70 per cent of paddy area in Assam must be infested by stem-borer,” said B K Sarma, a former ICAR scientist, who is also the author of the widely-acclaimed book ‘Rice Diversity of Northeast India’.

While farmers across the state have been using chemical pesticides, research has shown that their prolonged use has led to residual effect in rice. Trichogramma japonicum, is made to lay eggs in corcera, a host insect, after which the larvae are released in paddy plants affected by stem-borer. The larvae feed on stem-borer eggs, in the process saving the paddy stalks from dying due to damage to the stems.

Similarly, eggs of Trichogramma chillonis are also becoming popular among farmers facing the menace of a common pest called fruit-borer (Leucinodes arbonallis). The larvae of Trichogramma chillonis also feed on eggs of fruit-borer, in the process protecting brinjals from being affected. Farmers collect eggs pasted on cards, which are then released on the plants within 24 hours. The eggs hatch within 24 hours and the larvae start feeding voraciously on eggs of stem-borer and fruit-borer. There has been a three-pronged impact of this: while pest control has become safer, use of pesticides is going down, and the farm produce is definitely going to be organic.

“Set up in 2001, this laboratory does not intend to supply bio-agents to the farmers on a commercial scale. While we are looking at registration of our bio-agents from the Faridabad-based Central Insecticide Board, we also want to give the know-how to entrepreneurs for supply to the farmers,” said Bhaben Kalita, another scientist at the SBCL.

The laboratory produced 3.33 million Trichogramma japonicum and 2.5 million Trichogramma chillonis during 2009-10, with the demonstration programme itself benefiting about 500 paddy farmers and 2,000 brinjal growers. In case of brinjal, Trichogramma chillonis has also benefited the consumer in a significant way.

“Farmers are known to apply chemical pesticides on brinjals to make them shine more. But with Trichogramma chillonis, farmers do not need to do so as the bio-agent is also proved to have added some physiological benefits in size, colour and glaze of the brinjals,” Borthakur claimed.

“The efficacy of bio-agents identified and propagated by the SBCL has come as a major boon to farmers. The laboratory has worked wonders, especially when the whole world is talking organic. The state government has decided to strengthen the lab by providing more funds,” said state agriculture minister Pramila Rani Brahma.