It is that resistance time of the year again

Published on: 15:32PM Sep 10, 2009
You could see some humor in the matter if it did not cause so much distress to farmers. It can get bad enough for children to make candy money by picking the critters by hand. These caterpillars have seemingly limitless appetites, and leave just veins of leaves intact, to say nothing about fruit damage.

It is easy to find faults with farmers. They are accustomed to fix doses in terms of concentrations, so if a sprayer leaks pressure then the active ingredient per acre is just right for tolerance in the next generation. The latter hatch and eat hungrily even before their elders have pupated. Then there are new swarms of moths each dusk.

How do you distinguish adulteration from resistance? No individual farmer has the infrastructure for digging so deep, so it is natural to vent anger on the pesticide industry and trade. People feel duped because brands behave differently than when first launched. Each synthetic pyrethroid and neonicotinoid sells under some 100 trade-marks, and most of these are in English. You can meet scores of farmers who spray the same molecule over and again, albeit unwittingly.

The setting is just right for Endosulfan. The mode of action is refreshing from an efficacy perspective. The long duration of action brings welcome relief to farmers weary of spraying nearly every day. Aphids, brought in by interim rain, are kept under control as well. Endosulfan is affordable, which is a big plus for farmers burdened by debts and interest. However, the best aspect of Endosulfan is that it blends with P3-pollinators, predators, and parasites. You can see a surge in Chrysoperla adults and parasitized eggs in a field under Endosulfan cover.

You can have too much of a good thing when it comes to your favorite pesticide. Tolerance data changes every fortnight in the heat and humidity of an Indian September. It is important to switch back and forth between OPs, carbamates, and the rest of the armory. Many tracts do not have resistance-tracking laboratories. It is a kingdom-for-a-nail thing considering the mountains of cotton bolls and fruits of assorted crops lost to greedy lepidopterans.