Biologists stem the fight of the perilous False Codling Moth (FCM)

Pest and diseases can sometimes be very depressing to farmers if unmonitored properly. In crop farming for instance, one has to equip themselves with formidable instruments and knowledge of preventing or fighting these vampires from draining life out of the crops or else the yields would leave the farmer in a state of despair with massive losses.

One such pest is the False Codling Moth (FCM) which is currently causing havoc in various chili farms in the country. Even though the pest also destroys other crops like avocados, pineapples, mangoes and citrus, their devastating effect is mostly felt in the chilies.

According to David Mwenje, who is the Technical marketing consultant for Nairobi and Mt. Kenya region for Kenya Biologics Ltd, the False Codling Moth is a relatively new pest in the chili farming as it had not been experienced in the local farms before 2014. “The pest has been around in other crops but was first experienced in the local chilly farms in the late 2014,” said Mwenje.

The pest undergoes through a full life cycle of an insect which begins from the egg→larva→ pupa→ adult. During the larva stage, the pest would attack the chilly fruit from where it will bore a hole into the fruit while feeding and dwelling in it till it pupates where it will gradually spiral down with to the ground.

Initially, the female moth lays eggs on young fruit surface where they hatch after six days. Once they have hatched they start feeding on the chili. “The female lays eggs where the chili fruit is so as to enable the larvae find food easily,” said Mwenje.

During its metamophorsis, the FCM larvae bore the fruit thus destroying it completely. The larvae are categorized into different instars according to their lenghts. According to Mr. Mwenje, the first four instars are white in color but this changes to pink with a distinctive black head capsule. The FCM is most destructive at the larval stage.

Surprisingly, the adult FCM are most active in mating and egg laying between 5pm and 11pm.With a lifespan of up to 21 days before they become adults, it is obvious that the period is long enough for the pests to create a massive loss to the farmer.

Likewise, FCM thrives more in the tropical climates as compared to temperate regions. This has enabled it to multiply faster locally and other tropical countries as compared to the European and other countries that experience cooler temperatures.

“In the tropics, the FCM is able to feed all year round leading to faster maturity and consequently a faster breeding rate,” explained Mwenje.

Since the pest is resistant to pesticides, Kenya Biologics have come up with environmentally friendly ways of cubing the menace it causes to farms. They have developed a pheromone trap called CRYTRACK used for Mass trapping of the male moths before they mate with the female moth hence the eggs layed will be unfertilized.

By carefully studying the behaviours of the moths, it was imminent that whenever the female moths wanted to mate it would release a hormone known as Pheromonewhich attracts the male moths to come and mate.

Similarly, Crytrack which contain a substancewhich mimics the female’s pheromone is used to lure the male moths out of which they get trapped thus cannot mate anymore. “Once you have obtained the traps you can erect it into your farm where the chilies are grown,” continued Mwenje, “this should be done once they have started flowering to help you have a timely monitoring of the FCM’s presence. The traps should be erected at crop height.”

The method has been found to be very effective as it transcends the spreading of the FCM but also reduce the various risks associated with synthetic chemicals which include resistance and residue levels.

Mr. Mwenje recommends that for an effective control one requires seven traps per acre,though prior monitoring should be done to establish FCM percentage presence; with low percentage fewer traps can be erected.

All the same, there are other ways in which the FCM pest can still be controlled. One of them is by Mating disruption. Unlike in the Mass trapping where you target the males by trapping, here you confuse the males. The strategy here is to use the same substance that mimics the pheromone by smearing it on different locations thus confusing the males. In the end they will not be able to mate.

Equally important is the fact that these methods do not ultimately do away with spraying, rather a farmer should integrate both methods. “Trapping the FCM will help you reduce the amount of sprays you use as we have found that it reduces the pests by over 70%,” concluded Mwenje.

For the biologist, it is important for people to reduce the use of harsh chemicals so as to guarantee the safety of food and embrace more sustainable means of tackling pests and diseases. Even the sprayers themselves are also exposed to health risks coupled with many other challenges.