I have cultivated coconut in 2 acres about 6 years back near Ankola on the karnataka coast. The trees have started to bear nuts now.
I have a problem with the red palm weevil. This weevil has completely destroyed about 30-35 trees till date. Not only coconut but also Cashew. The female bores a hole in the tree trunk near or slightly above the root region and lays eggs inside the tree. When the eggs hatch the young feed on the core of the tree and destroy the plant. I have tried spraying Monocrotophos at regular intervals but it is not helping. I have also put lures to attract the males but that does not stop the females. But every year four to five trees succumb.
Is there any organic/natural way to stop these critters? Its gut wrenching to see the palms die. Thanks for your help.
Developed IPM package for red palm weevil that includes cleaning of palm crown periodically to avoid decaying of organic debris, proper cutting, splitting and burning of red palm weevil infested palms, treating of any wounds on the palm with coal tar and stem injection with 1% carbaryl.
Prophylactic leaf axil filling with 250 g marotti oil cake (Hydnocarpus sp.) + 200 g of fine sand in leaf axils around spindle during May, September and December has been found to be effective.
A red palm weevil lure ferrugineol was formulated at CPCRI. Unlike the sachets used in commercial lure the CPCRI lure was made of glass capillary of 6 cm in length and id. of 1.5 mm. Each glass capillary had 100 µl ie 78.5 mg of ferrugineol with the density of 0.76g/cc. CPCRI lure was cost effective as compared to the imported lures.
The role of kairamones in attracting the red palm weevils was established. Pheromone lure when placed in isolation did not yield desirable results; hence they had to be associated with food baits. Among the various phagostimulants that were evaluated to be used in tandem with pheromone lure, it was observed that macerated plantain (200gm) or sugarcane bits attracted more weevils (an average of 8 weevils/trap/week), whilst the pheromone trap without food bait had a lowest weevil catch of 1 weevil/trap / week.
As Sri mentioned. "200 g of fine sand in leaf axils around spindle during May, September and December has been found to be effective.
"
Here in kerala this technique was used on almost all small palms. now its difficult to even find a traditional nut harvester here.
Salt and SAND combination is the best. Sand actually gets stuck in between the joints of all the beetle, this is really effective.
(sea salt and not the powdered one, idea is it should be there inside the crown for a longer time and spread gradually to all parts of crown, keeps all sorts of pest away)
Problem is not every one can climb the crown of palm, however only smaller palms seem to get this problem not the really tall ones.
First clean the crown and then fill the above combination and use a iron rod or hard stick to fill the crown area with this mixture. some will immediately come out.
Alternately there is a device like a fish hook which is used to pierce the beetle and pull it out. Because of first hand experience I can make out if the palm is being damaged by any beetle and treat immediately in the initial stages.
I have been away and travelling since last few weeks. Interested people can send me PM if in-need of help, I should be able to assist.