PATOGENISITAS Achaea janata GRANULOSIS VIRUS (AjGV) TERHADAP ULAT PEMAKAN DAUN TANAMAN JARAK KEPYAR
Authors: INDRAYANI IGAA. , PRABOWO HERI , YULIANTI TITIEK 
Published: June 2020

<p>ABSTRAK<br />Achaea janata L. adalah hama penting tanaman jarak kepyar<br />(Ricinus communis) yang hingga kini pengendaliannya masih<br />menggunakan insektisida kimia secara intensif. Selain tidak efisien,<br />insektisida kimia juga menimbulkan pencemaran lingkungan. Untuk<br />mengatasi masalah tersebut, maka perlu cara pengendalian alternatif yang<br />selain efektif dan efisien, juga ramah lingkungan, seperti virus yang<br />diisolasi dari ulat A. janata (A. janata Granulosis Virus/AjGV). Penelitian<br />patogenisitas AjGV pada A. janata dilakukan di Laboratorium Patologi<br />Serangga Balai Penelitian Tanaman Pemanis dan Serat (Balittas) mulai<br />Januari - Desember 2012. Perlakuan terdiri atas enam konsentrasi AjGV,<br />yaitu 10 3 , 10 4 , 10 5 , 10 6 , 10 7 , 10 8 occlusion bodies (OB), dan satu kontrol.<br />Perlakuan disusun dalam Rancangan Acak Kelompok dengan empat kali<br />ulangan. Ulat A. janata yang digunakan adalah instar II, III, IV, dan V<br />masing-masing 90 ekor/perlakuan. Parameter yang diamati adalah<br />mortalitas dan bobot ulat, konsentrasi untuk membunuh 50% ulat (LC 50 ),<br />dan waktu untuk membunuh 50% ulat (LT 50 ). Hasil penelitian<br />menunjukkan bahwa AjGV patogenik terhadap A. janata, terutama ulat<br />instar II dan III dengan mortalitas berturut-turut 90 dan 86,7%. LC 50 AjGV<br />pada ulat instar II dan III masing-masing mencapai 1,0 x 10 3 dan 1,2 x 10 3<br />OB/ml, dengan LT 50 kedua instar sekitar 3,4-4,2 hari. Pengaruh infeksi<br />AjGV pada ulat A. janata efektif menurunkan bobot ulat hidup 57,9 dan<br />57,4% masing-masing pada ulat instar II dan III. Hasil penelitian ini<br />mengindikasikan bahwa sasaran yang tepat untuk pengendalian ulat A.<br />janata dengan AjGV di lapangan adalah pada saat instar II dan III.<br />Kata kunci: Achaea janata L, patogenisitas, instar, mortalitas</p><p>ABSTRACT<br />Achaea janata L. is an important insect pest of castor plant (Ricinus<br />communis L.) that was intensively controlled by chemical insecticide<br />caused inefficiency and an environmental polution. To solve the problems<br />it needs an effective, efficient and environmental friendly of alternative<br />control, especially using Granulosis Virus isolated from A. janata larvae<br />(AjGV). Study on pathogenicity of A. janata virus isolate against castor<br />leaf-eater, A. janata L. was conducted at Insect Pathology Laboratory of<br />Indonesia Sweetener and Fibre Crops Research Institute in Malang from<br />January to December 2012. The objective of study is to test the<br />pathogenicity of AjGV against A. janata larvae. Treatment consists of six<br />concentrations of AjGV, viz. 10 3 , 10 4 , 10 5 , 10 6 , 10 7 , 10 8 OBs/ml and one<br />control. Four instars of larvae, e.g. second, third, fourth, and fifth were<br />used in this study. Each treatments was arranged in Randomized Block<br />Design with four replications. Parameter recorded were mortality and<br />weight of larvae, LC 50 , and LT 50 . Result showed that AjGV was pathogenic<br />to A. janata larvae, mainly on second and third instar in resulting of 90%<br />and 86.7% of mortality, respectively. The LC 50 of AjGV on the second and<br />third instar was 1.0 x 10 3 and 1.2 x 10 3 OB/ml, respectively and the LT 50<br />was 3.4 and 4.2 days, respectively. Infection of A. janata virus reduced<br />the weight of both instar up to 57.9% and 57.4%, respectively. This result<br />indicated that the second and third was the suitable instars of A. janata<br />larvae for better control of AjGV in field.<br />Key word: Achaea janata L, pathogenicity, instar, mortality</p>