Keefektifan Nematoda Patogen Serangga Steinernema sp. Terhadap Achaea janata L., Serangga Pemakan Daun Jarak Kepyar (Ricinus communis) - Heri Prabowo; I.G.A.A. Indrayani (Buletin Tanaman Tembakau, Serat & Minyak Industri, 2013)
Penggunaan pestisida kimia yang cukup tinggi pada akhir-akhir ini telah menimbulkan dampak negatif ter-hadap lingkungan, sehingga pengendalian hama yang ramah lingkungan sangat diperlukan. Saat ini, peng-gunaan nematoda entomopatogen terutama Steinernema sp., membuka peluang untuk digunakan sebagai pengendalian Achaea janata. Tujuan dari penelitian ini untuk mengetahui keefektifan Steinernema sp. ter-hadap A. Janata , dilaksanakan di laboratorium patologi serangga Balai Penelitan Tanaman Pemanis dan Serat pada bulan Maret sampai dengan Agustus 2011. Penelitian menggunakan rancanagan acak lengkap (RAL) dengan empat ulangan. Setiap ulangan menggunakan 25 larva A. janata instar 2. Larva diekspose de-ngan berbagai variasi konsentrasi Steinernema sp. dan kematian larva diamati setiap hari sampai 120 jam setelah infeksi. Konsentrasi Steinernema sp. yang digunakan adalah 0, 50, 100, 200, 300, dan 400 JI/larva. Hasil penelitian pemberian Steinernema sp. pada konsentrasi 200, 300, dan 400 JI/larva cukup efektif untuk membunuh A. janata dengan persentase berkisar antara 80–94% mulai 48–120 jam setelah perlakuan. Se-makin tinggi konsentrasi nematoda, semakin tinggi mortalitas A. janata. Steinernema sp. dengan konsen-trasi 400 JI/larva paling efektif membunuh larva, menurunkan bobot larva, bobot pupa, jumlah telur yang dihasilkan, dan fertilitas telur. High intensity of chemical pesticide application has become a serious concern of environmentalists in recent years, because of various negative impacts of it. Therefore, environmentally friendly techniques of controlling insect pest are needed. Recently, the use of entomopathogenic nematodes, especially Steinernema sp., has created new possibilities of promising control techniques against insect pests. The aim of this study was to evaluate the effectiveness of Steinernema sp. to A. janata larvae in laboratory. This research was conducted at the Laboratory of Insect Pathology Laboratory of Indonesian Sweetener and Fiber Crops Research Insti-tute from March to August 2011. Tests used the 2nd stage larvae of Achaea janata, the leaf eater of castor (Ricinus communis). Treatment arranged in a completely randomized design (CRD) with 4 replicates. For each test used 25 larvae which were exposed to various concentrations of Steinernema sp. Concentration of Steinernema sp. used was 0, 50, 100, 200, 300, and 400 infective juvenile/larvae. Daily mortality A. janata larvae, larval and pupal weight, the number of eggs laid, and number of hatch eggs were recorded. Steinernema sp. on concentration of 200; 300; and 400 IJ/larvae was effective to cause mortality of A. janata larvae (80–94% mortality after 48–120 hours). The higher the concentration of the nematode the higher larval mortality. Steinernema sp. with concentration of 400 IJ/ larvae was effective decreasing larval and pupal weight, the number of eggs laid, and fertility of the eggs produced.