The government, in partnership with the Food and Agriculture Organisation, has launched a countrywide campaign to install traps which lure and catch moths behind fall armyworm (FAW) reproduction.

The intervention, under a project titled "Support to the Government of Rwanda in sustainable control and management of Fall Armyworm”, is worth $ 284,000 (about Rwf230 million).

The pheromone traps mostly target male moths because they are the ones responsible for reproduction through mating the female ones to produce larvae (or armyworm).

The traps reduce the male population and thus affect FAW reproduction.

"Because of the reduction in egg production, fewer caterpillars will be reproduced, thus a reduced effect on crops. The traps will also serve as an early warning system for the timely actions of FAW management,” Otto Vianney Muhinda, the assistant FAO Representative in Rwanda, told Saturday Times this week.

Pheromone is a chemical secreted by an animal that influences the behaviour or physiology of others of the same species by attracting members of the opposite sex or marking the route to a food source.

The rollout of the new technique started along with the beginning of the farming season B which commenced late last month.

On February 16, FAO warned that, if left unchecked, FAW could push more than 300 million people into hunger, and lead to annual economic losses of up to $4.8 billion from maize production alone, and said that the pest infested millions of hectares of maize in Africa.

FAW can feed on 80 crops, including maize, rice, sorghum, millet, sugarcane, vegetable crops and cotton; but it prefers maize.

"Maize is the most important food security crop and it is now also picking momentum to become a nutrition security crop,” FAO stated.

Up to 1,200 pheromone traps will be provided to farmers. The installation of the traps has already started in the districts of Nyagatare, Nyanza and Muhanga, and will be rolled out to other districts later.

Realising that the armyworms could cause about 30 per cent yield loss to his plantations, John Muvara, a farmer from Nyagatare District, Eastern Province, said he decided to intensively apply pesticides to avert the damage.

However, though it helped him contain the pest, the pesticide he applied on 12 hectares of his maize plantation, last season cost him over Rwf1 million.

"I lost only about 1 per cent of my maize yields because I started controlling the pest through picking and pesticide use. I sprayed the pesticides three times using between three and four litres per hectare. A litre of pesticide cost me Rwf10,000,” he told Saturday Times.

This year, Muvara is growing maize on 20 hectares. He said he had already set the traps in his field, thanks to the Ministry of Agriculture and FAO.

"The traps help reduce the population of the moths in the maize farm by preventing the production of the larvae (armyworm) which damage maize,” he said, adding that one trap attracts about 80 moths in less than a week.

Timing critical

Muhinda said timing is a key factor in the management of FAW. The pheromone traps are useful in detection of early pest infestations, defining areas of pest infestations, tracking the buildup of a pest population and help in decision making for pest management.

"Pheromone traps are safe, environmentally friendly, easy to use and are an inexpensive valuable tool for monitoring armyworm population,” he said.

According to Rwanda Agriculture Board (RAB), the new technique is making the fight against armyworms an integrated approach as it complements hand picking and application of pesticides.

The Ministry of Agriculture and Animal Resources projects that, in 2018, Rwanda expects 775,000 tonnes of maize from about 258,000 hectares of consolidated land.

The pest was first reported in Rwanda in February, 2017.

Last year, RAB projected a harvest amounting to about 220,000 tonnes of maize from an estimated 65,000 hectares of land countrywide in second season, but about 5 per cent of the produce, amounting to 10,000 tonnes, was destroyed by armyworms.

To expedite interventions to contain the pest, Rwandan Defence Forces used its aircraft to supply pesticides across the country.

editorial@newtimes.co.rw