The agriculture department’s rather slow action on reports of the black headed caterpillar and its inaction against unregistered coconut sapling growers is the likely reason why the scientifically known Opisina arenosella or Nephantis serinopa has managed to make inroads into coconut plantations. This pest attacks coconut leaves and makes galleries within its leaflets during summer months and makes the crown of leaves appear that it has been burnt.
According to experts it is the larval stage of the black headed caterpillar pest that causes serious damage to the plant, while the adult moth have a short life span and are harmless.
History shows that the first record of this pest in India was in 1907 and in Coimbatore on Palmyra plants, and first reports on on coconut palms came from Bapatala, Andhra Pradesh in 1909. Insects were found to occur in alarming numbers along the coastal belts.
Experts feel that the insect most probably entered Goa again through the coconut seedlings being sold by unregistered vendors from Andhra Pradesh. They do a roaring business by moving door to door and booking orders for delivery.
during the monsoon season. The caterpillar multiply rapidly during the summer months when these traders are no longer to be seen.
The Government has enacted the Goa Fruit and Flower Nurseries [Regulation] Act, 1995, that mandates that all nurseries doing business in Goa should be registered. However no action is seen to be taken on roadside vendors of ornamental and fruit plants as well as coconut seedlings seen moving with push carts all over Goa.
The Directorate of Agriculture is the enforcing authority under this act and the Zonal Agriculture Officers in each taluka [except Mormugao that continues to be served by Z.A.O. Margao when even the new taluka of Dharbandora has a Z.A.O. of its own] is the one to enforce it.
There is a Biological Control Laboratory at Ela Farm, Old Goa, in the Directorate of Agriculture. Sources say that it multiplies Trichogramma sp. wasps that do not have demand from the farmers but has not multiplied Bracon sp that the Director of Agriculture Satish Tendulkar himself has reportedly recommended as a solution to this pest even as he reportedly told media that this problem usually starts during the summer months and that they have “ascertained the actual cause,” and agriculture inspectors are to give him the report shortly.
.Mr. P.K. Desai, Director of Agriculture from 1993 to 95 and an expert in pest management, and who manages the Ashish Agro Associates in St. Inez dispensing advice and inputs to farmers, says:
“The best control for this insect pest is to have a Paddeli to harvest the coconuts and tender coconuts, cut off the severely affected coconut fronds and then spray a systemic insecticide like Monocrotophos on the crown of coconut leaves during the remaining part of the summer. Once the monsoon rains start, the insect will recede as it multiplies mostly during hot and dry summer months.”
According to a research paper in Bangalore the coconut black-headed caterpillar (bhc) Opisina arenosella is one of the major pests of coconut palms causing considerable damage to coconut industry. It argues that though effective control has so far been elusive, the discovery of a successful method of control of this pest by systemic application of ‘Soluneem’, the first water soluble, non-toxic neem pesticide is reported. A single dose of systemic administration of the formulation containing 3000 ppm of azadirachtin A in aqueous solution at the base of the trunk translocated the biopesticide to the crown within 24 h. A highly significant reduction in the larval population, moult inhibition, reduction in adult emergence and malformation in the emerged adults was recorded in Soluneem-treated trees. The protection lasted for more than 120 days with no phytotoxic symptoms to the treated palms and Soluneem was safe for natural enemies.
Anotehr controlling factor or cure is Trichogramma which is despatched in the form of parasitised moth eggs. The eggs are distributed in capsules and are sold by the sheet. One sheet comprises 60 capsules, each containing 1000 parasitised moth eggs.
Each capsule should be stapled through one corner to a leaf or post (tomatoes) or dropped into a whorl (sweet corn). In hot weather, a shady spot should be selected. The wasps will gradually move downwind, so place any extra capsules along the windward boundary of the crop. [H]