How whiteflies came, saw and conquered India’s crops

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How whiteflies came, saw and conquered India’s crops


The first reported invasive spiralling whitefly is now distributed all through India besides Jammu & Kashmir

It was early summer time in 2016 when Selvaraj Krishnan and his crew from ICAR- National Bureau of Agricultural Insect Resources got down to examine a coconut discipline in Tamil Nadu. They had been surveying the world for the whitefly, which was lowering the yield and wreaking havoc: the whitefly.The first invasive whitefly reported from Kerala in 1995 has now unfold throughout the nation, and a examine has now detailed the injury attributable to the pest.

Patterns of incidence

Extensive research had been carried out from 2015 to 2020 throughout the nation to know the patterns of incidence, the depth of the infestation and their pure enemies. The crew visited a minimum of 5 to 10 areas in every district and 5 to 12 districts in every state together with the islands of Lakshadweep. They extracted genomic DNA from particular person grownup whiteflies and defined intimately about eight invasive species present in India.

“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. Also nowadays with globalisation, it is also possible that tourists may have brought the insect along with plants. Out of curiosity, people randomly pluck and bring tiny plants which lead to the accidental introduction of invasive species. We need to create awareness among the travellers,” explains R. Sundararaj from the Forest Protection Division at ICFRE-Institute of Wood Science and Technology. He is the primary writer of the paper revealed in Phytoparasitica.

The crew notice that the primary reported invasive spiralling whitefly Aleurodicus dispersus is now distributed all through India besides Jammu & Kashmir.

Similarly, the rugose spiralling whitefly which was reported in Pollachi, Tamil Nadu in 2016 has now unfold all through the nation together with the islands of Andaman Nicobar and Lakshadweep. Recent experiences have indicated that roughly 1.35 lakh hectares of coconut and oil palm in India are affected by the rugose spiralling whitefly.

The crew discovered that the host vary of all the invasive whiteflies was rising resulting from their polyphagous nature (potential to feed on numerous sorts of meals) and prolific breeding.

Aleurodicus dispersus and Aleurodicus rugioperculatus have been reported on over 320 and 40 plant species, respectively.

Invasive whiteflies

Other invasive whiteflies had been additionally discovered to develop their host vary on helpful vegetation species, particularly coconut, banana, mango, sapota, guava, cashew, oil palm, and decorative vegetation comparable to bottle palm, false fowl of paradise, butterfly palm and essential medicinal vegetation.

The crew additionally carried out explorative surveys to search out novel organic management of those invasive pests. “The whiteflies are difficult to control by using synthetic insecticides, and hence currently naturally occurring insect predators, parasitoids and entomopathogenic fungi (fungi that can kill insets) are being used. They are not just environmentally friendly but also economically feasible,” explains Selvaraj Krishnan, corresponding writer of the paper.

“Entomopathogenic fungi specific to whiteflies are isolated, purified, grown in the lab or mass-produced and applied into the whitefly infested field in combination with the release of lab-reared potential predators and parasitoids,” he says.

He provides that steady monitoring of the incidence of invasive species, their host vegetation and geographical enlargement is required, and if required, import of potential pure enemies for bio-control programmes may also be carried out.



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