Status Teknologi dan Prospek Beauveria bassiana Untuk Pengendalian Serangga Hama Tanaman Perkebunan - SOETOPO, DECIYANTO; INDRAYANI, INDRAYANI (Puslitbang Perkebunan, 2007)
ABSTRAKPengendalian hama dengan insektisida kimia telah menimbulkan banyak masalah lingkungan, terutama rendahnya kepekaan serangga terhadap insektisida kimia, munculnya hama sekunder yang lebih berbahaya, tercemarnya tanah dan air, dan bahaya keracunan pada manusia yang melakukan kontak langsung dengan insektisida kimia. Salah satu alternatif pengendalian yang cukup potensial adalah penggunaan patogen serangga, khususnya cendawan B. bassiana. Mekanisme infeksinya yang secara kontak melalui kutikula dan tidak perlu tertelan oleh serangga menyebabkan B. bassiana menjadi kandidat utama untuk digunakan sebagai agen pengendalian berbagai spesies serangga hama, baik yang hidup pada kanopi tanaman maupun yang di dalam tanah. Rata-rata patogenisitasnya terhadap hama sasaran cukup tinggi, sehingga pemanfaatannya dalam pengendalian serangga hama perkebunan, seperti kapas, kelapa sawit, lada, kelapa dan teh memiliki prospek sangat baik. Untuk pengendalian ulat penggerek buah kapas, Helicoverpa armigera telah ditemukan dua strain isolat, yaitu Bb4a dan BbEd10 yang efektif membunuh 80-87,5% ulat H. armigera hasil uji di laboratorium, dengan masing-masing LT50 mencapai 8,96-9,62 hari dan 19,69-22,27 hari dibanding strain B. bassiana yang lain (19-48 hari). B. bassiana juga efektif untukm pengendalian serangga hama kelapa sawit(Darna catenata), penggerek batang lada (Lophobaris piperis), dan ulat pemakan tanaman teh (Ectropis bhurmitra). Konidia B. bassiana dapat diaplikasikan dengan cara disemprotkan pada kanopi tanaman, ditaburkan pada permukaan tanah, atau dicampur dengan tanah atau kompos. Temperatur dan kelembaban adalah faktor abiotik yang sangat berpengaruh terhadap pertumbuhan konidia B. bassiana, tetapi cahaya melalui panjang gelombang sinar ultraviolet juga berpotensi merusak konidia sehingga aplikasi pada pagi (< pkl. 08.00) atau sore hari (> pkl. 15.00) dapat menghindari kerusakan. B. bassiana aman bagi serangga bukan sasaran, terutama serangga berguna dan musuh alami. Temperatur dan kelembapan yang lebih stabil pada ekosistem tanaman perkebunan akan sangat mendukung peran B. bassiana dalam pengendalian hama utama tanaman perkebunan sehingga prospek pengembangannya sangat baik.Kata kunci: Beauveria bassiana, status teknologi, prospek, hama perkebunan. ABSTRACTStatus, technology and prospect of ecofriendly entomopathogenic fungus B. bassiana against insect pests of estate cropsChemical insecticides for pests control are causing environmental problems, such as reducing susceptibility of insect pests to a number of chemical insecticides, outbreaks of secondary pest, air and soil pollution, and human poisoned due to directly contact with the pesticides. Insect pathogen, a pest control bioagent, can be used as an alternative component control for reducing of chemical insecticide usage. The entomopathogenic fungi, B. bassiana (Bals.) Vuill. is currently being developed as a potential of alternative bioinsecticide. Mode of action of the fungi is initially started by adhesion and penetrating of the spore through insect cuticule, and its mycelium then develop inside the insect body prior the insect death. Its conidia will grow soon after the insect die. High pathogenicity will show when B. bassiana expose to appropriate target pests. Several Indonesian strains and isolates of B. bassiana have been proven to be pathogenic against several major insect pests of cotton, oil palm, pepper, coconut and tea. Two B. bassiana isolates, viz. Bb4a and BbEd10 were found to be effective against cotton bollworm, H. armigera with the average percentage of mortality by 80-87.5% based on laboratory study. Both the LT50 and LT90 of the two isolates were 8.96-9.62 days and 19.69-22.27 days, respectively and these LT were shorter than that of other isolate, Fb4 (19-48 days). B. bassiana was also effective for control of the oil palm larvae (D. catenata), pepper stem borer (L. piperis), and tea leaf caterpillar (E. bhurmitra). B. Status, Teknologi, dan Prospek B. Bassiana Untuk Pengendalian Serangga Hama (D.Soetopo dan IGAA Indrayani) bassiana can be applied by spraying method over the plant canopy, applied as soil treatment, or by mixing the conidia with compost. Temperature and humidity are the abiotic factors that able to influence the growth of conidia. B. bassiana spore is less active or even inactive when directly exposed to ultraviolet, therefore spraying conidia in the early morning (< 08.00 a.m) or in the evening (> 15.00 p.m) may avoid the reduction of conidia activity. B. bassiana is also safe to non-target insect including beneficial insect and natural enemies. Temperature and humidity are more stabil within estate plantation ecosystem and both will support the fungus epizootic development. Therefore using B. bassiana seems to hold great promise in controlling the major insect pests of estate crops.Key words: Beauveria bassiana, status of technology, prospect, insect pest, estate crops.