False coddling moth (FCM) – it certainly doesn’t roll easily off the tongue and probably leaves most laymen stone cold. But this small insect, originally from sub-Saharan Africa, warrants the rigorous preventative measures that the South African citrus team has been driving for the last 25 years.
FCM is a citrus fruit pest that loves macadamias, avocadoes, stone fruit, peppers and various other crops. Though unsightly, it has no impact on human health but, if left undetected, infestation shortly before a harvest can cause decay of citrus and other fruit, once it has
been packed and shipped to export markets. And this could certainly wreak untold havoc on revenue. But why are we even talking about FCM, and why now?
When it comes to risk mitigation in the citrus industry, citrus black spot (CBS) has certainly dominated in the press. But due to the EU’s recent proposed regulatory measures around FCM, mention of the pest is likely to become more frequent as the South African citrus narrative unfolds.
FCM established itself in Citrusdal in 1976, this being South Africa’s oldest citrus exporting region. Some growers suffered substantial losses of up to 50-60% of their crops.
The FCM adult female lays single eggs on fruit and after hatching, larvae penetrate the fruit almost instantly. Being an internal feeder, FCM larvae display few symptoms to betray their presence. When larvae exit the fruit to enter the pupa stage, the rind around the point of
infestation turns yellowish-brown, indicating decay and collapse of the tissue. Infestation will cause fruit to drop off the plant, resulting in considerable crop losses. FCM requires consistent host availability to keep propagating. As such, populations of FCM drop significantly when citrus or other crops are out of season and can even disappear completely.
However, viability of FCM is subject to various contributory factors, such as the ability to
complete its life cycle, the climate, and other region-specific factors.
XSIT is one of the most effective ways in which our citrus growers combat FCM. It was introduced as an initiative of Citrus Research International (CRI) to market the Sterile Insect Technique (SIT). It contains the spread of FCM effectively by reducing its population. Through XSIT more than 5 million sterile moths are produced daily, which outnumber wild moths in the treated areas by at least 10 to 1. Mating between the two stunts reproduction, resulting in
an annual drop in FCM population.
Sterile moths are spread by being dropped by fixed-wing aircraft, helicopter or dispersed from four wheelers on contracted orchards. The institution uses a computerised statistical/mathematical program, as well as GPS to ensure efficiency. In South Africa this does have a significant cost implication for growers, because Government doesn’t subsidise the process.
For the last two decades CRI has continued to focus its efforts preventing FCM.
With 92% of South Africa’s R17.6bn citrus industry turnover coming from export, we’re under no illusion about the importance of nurturing trade relations, especially with the EU (our biggest citrus export destination). Therefore, we will continue to enhance our risk mitigation efforts as we seek to comply with trade regulations. And with more than 70 000 on-farm jobs at stake, meeting these requirements remains firmly on our radar.
So, the next time you hear false coddling moth mentioned, may it not only roll better off your tongue, but we hope it reminds you of the tireless efforts of our citrus growers to keep this small but destructive insect at bay.