Biological Control of coconut Hispine Beetle (BrontispalongissinaGestro)
Research Title : Biological Control of coconut Hispine Beetle (BrontispalongissinaGestro)
Researcher : Krissana Ruang-Rit
Office :
Research Grants : Research and Innovation for Transfer technology to Rural Community Project
Year : 2007
Biological Control of coconut Hispine Beetle (BrontispalongissinaGestro)
Abstract
Surveys of Brontispalongissima distribution on coconut palms, betel nut palms and oil palms in PrachaubKirichan and Chumphon provinces were carried out during two consecutive seasons. The first survey was done on the late rainy season. The results showed that coconut palms were attacked the most by the beetle, followed by some betel nut palms neighboring the coconut outbreak areas. But oil palms were not affected. The severely outbreak area in PrachaubKirichan was 20.1% and the total outbreak area was 58.6%, while in Chumphon the severely outbreak area and total outbreak area were 3.1% and 23%, respectively. The second survey was done on the dry season. The rate of outbreak was lower than the rainy season. In PrachaubKirichan the severely outbreak area was 10.7% while the total outbreak area was 48.06%. In Chumphon, the severely outbreak area and total outbreak area were 1.5% and 17.5%, respectively. Before the second survey was carried out the DOA released a great number of parasitoids all over the outbreak area and the parasite could establish and control the beetles. The rearing of B. longissima by culturing the beetles using detached leaves of coconut palms, betel nut palms and oil palms were carried out. It was shown that the beetles could complete their life cycles using leaves from coconut palms. But the beetles could not complete their life cycle on oil palms.
Study was carried out on growth and survival rate of Coconut Hispine Beetle by substituting young coconut leaflets by old coconut leaflet and three species of aquatic plants. The results revealed that the old coconut leaves and cattail leaves could be used to substitute for young coconut leaves. But the survival rate was lower than fed by young coconut leaflets. However, umbrella plant leaves and bulrush leaves could not be used to substitute for the young coconut leaflets. This was because the larvae could not survive during the process of inducing mummies using A. hispinarum. The coconut hispine beetle rearing with young coconut leaflets, old coconut leaves and cattail leaves could be transfermed to mummies at the rate of 100%, 100%, and 58.02%, respectively. Parasitoids emerged from the mummies were 43.94, 38.13, and 15.17 parasitoids per mummy, respectively. The experiment was also aimed at studying the influence of relative humidity on the emergence of A. hispinarum from the mummies of coconut hispine beetles. The result showed that relative humidity of 86-90% yielded the highest average number of parasitoids that emerged from the mummies. The parasitoids emerged from the mummies of control treatment, which was kept at 81-85% relative humidity, was significantly lower than the treatment at 86-90% and 91-95% relative humidity (p<0.05). However, there is no statistically difference between treatment at 86-90% and 91-95% relative humidity.
Test of earwig to coconut hispine beetle control. The result showed that earwig highest killed pupa stage and 6:30 of earwig and beetle is proper ratio. Parts of Metarhiziumanisopliae and Beauveriabassiana to control beetle. The both of fungi higher control than B. bassiana and M. anisopliae at 2×106 conidia/milliliter.