New technique developed to fight white grub infestation in sugarcane

By Umashankar Mishra

New Delhi: OOver the years, sugarcane farmers have been fighting a losing battle against white grub infestation. Now Indian researchers have developed a new technique to deal with the problem.

Scientists at the Indian Agricultural Research Institute (IARI) have used a biological mixture of cadavers of an insect called Galleria malonella infected with a set of parasites called entomopathogenic nematode (EPN) to kill white grub.

Generally, synthetic pesticides such as organophosphate and carbamate are used to deal with this problem. But, the pest was developing resistance to them. A search was conducted for an alternative strategy. Studies across the world have shown that the EPNs are parasites of white grub and could be considered as an agent to control them.

"So far this technology has not been commercialized. New jobs can be created especially in rural India, if young farmers come forward to produce these bio-control agents by learning the techniques. Farmers can get training free of cost from Division of Nematology, IARI," he added.

While white grub is a parasite dependent on sugarcane, EPN is its parasite. Two major species of EPN - heterorhabditis and Steinernema, have generated much interest as potential bio-control agents as they carry lethal symbiotic bacteria in their guts, which is toxic to white grub.

As part of their study, the researchers multiplied EPN in vivo, on a small scale, on the larvae of a pest called Greater Wax Moth (Galleria melonella). Galleria is the conventional host for in vivo multiplication of EPNs due to its several attributes, not the least of which is the ease with which it can be reared in plastic boxes or wooden trays on a diet of wheat/corn flour, wheat/rice bran, wax, yeast, honey and glycerol.

Galleria pests were infected with fresh cultures of EPN. The infection process involved the release of Galleria onto large plastic trays moistened with the nematode suspension. Galleria died within 24 hours and were ready for release in the fields.

Dr. Sharad Mohan, who led the project, told India Science Wire that several farmers have been trained and they are successfully producing EPN-infected Galleria at their homes. So far this technology has not been commercialized. New jobs can be created especially in rural India, if young farmers come forward to produce these bio-control agents by learning the techniques. Farmers can get training free of cost from Division of Nematology, IARI, he added.

Field trials were conducted in seven different districts of West Uttar Pradesh- Ghaziabad, Meerut, Amroha, Saharanpur, Gajraula, Bulandshahar and Hapur between 2008 and 2014. The results have proved very positive. White grub population decreased by 69 percent per acre and sugarcane yield increased by 60 percent.

For implantation in one acre farm, 3,000 EPN-infected Galleria cadaver are required. This costs around Rs. 1,500. During field trials implantation was done around sugarcane clumps in the month of June. In cases of acute infestation, reapplication after one month is recommended.

A report on the study is published in the latest issue of journal Current Science. The research team also included Akanksha Upadhyay, Aarohi Srivastava and K. Sreedevi. (India Science Wire)

Latest Tweets @Indiasciencewiret