New farm pests emerging as a food-security threat, maize yield hit
Global farm threats are knocking on India’s doors in the form of newer pests, some of them voracious crop-destroyers that can roil farm production and farmers’ incomes, prompting officials to call for stricter quarantine checks for biological imports.
Among a flood of new pests that has emerged over the past couple of years, one has been super-invasive and the most threatening: the fall armyworm. The worm, cited by the UN Food and Agricultural Organisation (FAO) as a “food security nightmare”, has cut maize yields by up to 30% in key producing states such as Karnataka, Andhra Pradesh, Bihar, Maharashtra and Telangana, experts said.
The pest has spread rapidly across states after being first spotted in July 2018 in three maize hubs of Karnataka: Hassan, Bellur and Shimoga. “It’s breaching new frontiers,” said AN Shylesha of the National Bureau of Agricultural Insect Resources.
The only region so far free from infestation – food bowl states in northwest India – is being fast raided by the worm, which can travel thousands of kilometers aided by winds alone.
On August 1, a pest sample from a Uttar Pradesh farm tested positive, an official said. “We confirmed it to be the fall armyworm. In one season alone it had destroyed 15-20% of India’s corn. It has a big potential for causing yield losses,” said Shylesha.
A molecular profiling of the pest by the Indian Council of Agricultural Research revealed its origins: a 100% match with populations in Costa Rica and Canada, although the pest was first identified in Africa in 2016.
The fall armyworm has a voracious appetite for crops. According to an FAO alert, it has spread to more than 30 countries since being discovered, potentially destroying $5 billion worth of corn, its favourite snack.
Shylesha said several new pests had appeared in India over the past couple of years, which he attributed to increasing trade in biological materials and global travel. These include the coconut-destroying spiraling white fly, the erlophyld mite, which attacks many crops, the woolly apple aphid, the berry borer beetle that drills into coffee, tuta absoluta, which eats tomato plants, and the papaya-munching mealy bug.
Shylesha and his team were in Kathmandu this week to help the country secure its farms since the pest has devoured maize crops in the Himalayan country too.
“Maize farmers who have reported incidence of infestation by this pest have cited yield losses of up to 30%. In Karnataka, the losses have been reported to be 30%, while in Andhra Pradesh, up to 27% losses,” said Bhagirath Choudhary, director of the South Asia Biotechnology Centre (SABC).
India produces over 20 million tonne of maize annually and the crop is a major source of farm income. SABC has launched a programme to popularise a special trap containing a chemical produced by female fall armyworms to ensnare male pests. “This is like a signalling device. If you have the pest in the trap, you know your farm has been infested.”
The organisation has launched a national website, fallarmyworm.org.in, to help mount a coordinated control programme.
The Indian Council of Agricultural Research has launched a national programme to rapidly breed pests that feed on the fall armyworm as the primary cost-effective defence. “Biocontrol multiplication units in each state have embarked on a programme to rapidly increase the population of these pests. But the worry is that it is now present in almost all states,” Shylesha said.