Leaf rot and fruit loss in areca nut tree causes worry among farmers in Kasaragod

Neeleshwaram: Areca nut farmers in the district are worried as fruit rot (mahali) is widely spread in the plantations in the hilly areas of Kasargod – Kannur districts. Experts say that fruit rot became severe due to the heavy rains this year and also because the usual preventive measures against the fungal disease wasn’t effectively done before the rains. 

Symptoms
Fruit rot disease in areca catechu trees is a common fungal disease mainly caused by phytophthora species. Growth of stark white patches on the fruits and flowers is the main symptom of this disease. The fruits and flowers affected by this disease rot away gradually. Besides, the fungus spreads to the stems where the leaves are attached, during the end of rainy season, leading to rotting. This disease has been spreading swiftly among the trees in the same plantation as well as multiple plantations in the same area. 

Preventive measures
One percent Bordeaux mixture could be sprayed as a preventive measure. The first spray should ideally be done before the onset of monsoon and the rest could be done at 25 – 30 days intervals. Ensure good drainage in plantations as waterlogging favours fungal growth. Sanitation is also key in protecting the trees from fungal diseases and fruit rot. Besides, fallen infected nuts and plant debris should be collected and destroyed regularly to prevent the spread of spores. 

The fungicide should be sprayed only when the skies are clear and sunny. Potassium phosphonate 50 SC (5 ml in one litre of water) or metalaxyl and mancozeb 80 WP (two grams in one litre water) could be mixed and sprayed in the plantations. You could repeat the same process 15 days later if the fungal infection gets severe. After two weeks, mancozeb 80 WP (two grams in one litre water) or mandipropamid 23.4 SC (one milligram in one litre water) could be sprayed. Besides, Dr P K Sajeesh, assistant professor of plant pathology at the College of Agriculture, Padannakkad recommends adding lime or dolomite to reduce the soil’s alkaline nature and also to enrich it with potash-based manure to boost the plant’s immunity. 

Meanwhile, College of Agriculture dean Dr T Sajitha Rani said that the farmers could contact the college under the Kerala Agriculture University for clearing doubts.