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Extensive studies were carried out from 2015 to 2020 across the country to understand the patterns of occurrence, the intensity of the infestation and their natural enemies.

Research

• The team visited at least 5 to 10 locations in each district and 5 to 12 districts in each state including the islands of Lakshadweep.
• They extracted genomic DNA from individual adult whiteflies and explained in detail about eight invasive species found in India.

Finding

• Most of these species are native to the Caribbean islands or Central America [or both].
• It is difficult to pinpoint how they entered our country. Most probably a nymph or baby insect may have come along with imported plants. 
• The first reported invasive spiralling whitefly Aleurodicus dispersus is now distributed throughout India except Jammu & Kashmir.
• The host range of all of the invasive whiteflies was increasing due to their polyphagous nature (ability to feed on various kinds of food) and prolific breeding.
• Invasive whiteflies Other invasive whiteflies were also found to expand their host range on valuable plants species, especially coconut, banana, mango, sapota, guava, cashew, oil palm, and ornamental plants such as bottle palm, false bird of paradise, butterfly palm and important medicinal plants.

What is whitefly?

• It is a small (1-2 mm) white-coloured insect affecting cotton, and also occurring on vegetables and other crops in tropical and sub-tropical regions.
• The whitefly sucks sap from the phloem or living tissue carrying organic nutrients, causes yellowing and upward curling of the leaves.
• The insect also deposits sticky honey dew excretion, which promotes sooty mould fungi that interfere with photosynthesis.
• Sticky cotton makes ginning and milling difficult. In north India, whitefly is present throughout the year, due the wide range of crops grown, shifting from one crop to the other.
• But more damage is caused by the cotton leaf curl virus that is transmitted by the same insect. 

Source: The Hindu