Helping Coconut farmers with a Long Distance Air Spray to Eliminate Pests that feed on Coconut

The long distance air spray to eliminate pests was designed by Mr. Pongnipat Kaowun, Mr. Suriya Tamek, and Mr. Boonyarit Boonyawet, fourth year students in the Department of Agricultural Engineering, Faculty of Engineer at RMUTT, with consultation from Dr. Kriengkrai Samsimuang.

            Mr. Pongnipat Kaowun, the representative of the air spray said that coconuts are vital to the Thai economy. Asian countries are also important coconut exporters with Thailand being the 7th largest exporter of coconuts in the world, and the 5th largest exporter in Asia. However, there are problems with coconuts grown in Thailand due to numerous pest infestations such as Brontispa Longissima Gestro, a thin dark brown insect that gnaws on young coconut shoots, halting its growth. Additionally, Coconut Black-headed Caterpillars gnaw on coconut leaves until the leaves are dry while Rhinoceros Beetles penetrate the cone of the coconut through the coconut leaves, making the leaves break, and the coconut will rot and eventually die.

            Field research about methods to eliminate pests that feed on coconut, held in Photharam district, Ratchaburi province, reveal that farmers sprayed chemicals on coconut shoots. Farmers also attached a spray nozzle on coconut shoots, let out insects such as parasitoids, and sprayed chemicals themselves, but it lacked accuracy in eliminating pests and was highly dangerous as farmers were unprotected with inefficient equipment.

            Thus, the Board decided to design a prototype of a long distance air spray that could eliminate pests that feed on coconut, which may also decrease labor, minimize damage caused to those that have to use the spray, and increase the efficiency of eliminating pests. The prototype, which uses a 10 engine horsepower, includes the structure of the air spray, power system, storage tanks, pump, crane, spray nozzle complete with a remote system, and crane control system.

            To operate the machine, one has move and control the spray to the designated area, near the coconuts, and control the crane and control motor. Then, store the sling until it reaches the top of the coconut by using a remote camera mounted to the crane. When the spray area has been defined, adjust the spray nozzle to the area where pests are present, and control the pump so it sprays the appropriate amount of chemicals required for each tree.

            Results from testing the spray and duration of moving it revealed that the ideal distance between the spray nozzle and the target is one meter for a coconut tree that is five to nine meters high, using a pressure of 1.5 bar. It can spray 2,712 Liters (L)/sec, with the fastest movement of 1.5 Km/hour. The rate of fuel consumption is 0.58 L/hour and covers an area of 0.353 acres/hour.

            This air spray can be used with coconuts that are 10 meters high and has been designed and developed to help farmers solve their problems. The price of the design and development is 28,000 baht per machine. Those that are interested and would like to ask for more details can contact the Agricultural Engineering department at 02-549-3581.