The cotton crop in Maharashtra is facing whiteflies attacks and if enough attention is not provided by the State Government then the problem could aggravate and cause significant economic damage, senior Maharashtra Government officials told BusinessLine.
Changes in weather and higher moisture content in the air coupled with the use of synthetic Pyrethroids for killing pink bollworms has lead to the ingress of whiteflies, such pesticides act as a booster for the flies. The cotton shrubs also become vulnerable to attacks by whiteflies if farmers mix different pesticides and spray the cocktail on the shrubs,
The problem could soon reach an economic threshold (ET), defined as the insects' population-level at which the value of the crop destroyed exceeds the cost of controlling the pest. ET is an indicator for initiating preventive measures. In Punjab, whiteflies have already destroyed large areas of cotton crop in the last four years, the officials said.
When whiteflies attack a cotton shrub, it leads to the curling of leaves, reduces plant vigour by affecting photosynthesis and lint gets contaminated with secretions from the flies. It also makes the shrub vulnerable to fungal attacks and leaf curl virus disease. The flies suck the sap from the cotton shrub's phloem or living tissue that transports food made in the leaves through photosynthesis to other parts.
The officials said that the attacks have been detected in all major cotton grown areas of Vidarbha including Pandharkawda in the Yavatmal district. The extent of damage is still being assessed. The whiteflies attacks have been detected in Maharashtra in the last five years but this time it is more virulent, which could cross ET.
In areas where an excess amount of insecticides have been used, whiteflies attacks have been stronger,
At the local level, farmers are being sensitized to avoid spraying of synthetic Pyrethroids, use of less harmful methods such as sticky traps, which are hard paper consisting of a sticky glue layer mounted on a piece of cardboard. These cardboards are tied to the shrubs on which the flies get attracted due to its yellow colour and their wings get immobilised, which eventually kills them, the officials said.