BIOEKOLOGI DAN PENGARUH SERANGAN Sanurus indecora TERHADAP KEHILANGAN HASIL JAMBU METE

Jambu mete (Anacardium occidentale L.) merupakan salah satu komoditas ekspor. Salah satu kendala dalam produksinya adalah serangan hama. Di Nusa Tcnggara Barat (NTB), Sanurus indecora telah menjadi isu utama dan dianggap sebagai salah satu hama yang scrius menyerang tanaman jambu mete. Untuk mengetahui bioekologi S. indecora dan pengaruh scrangannya terhadap kchilangan hasil jambu mete telah dilakukan penelitian di pertanaman jambu mete di Dusun Sambik Rindang, Desa Salut, Kecamatan Kayangan, Kabupaten Lombok Barat, NTB dan di laboratorium Entomologi, Balai Penelitian Tanaman Rempah dan Obat, Bogor dari April sampai Oktober 2003. Penelitian ini terdiri atas dua kegiatan penelitian yaitu di lapang dan di laboratorium. Kegiatan di lapang adalah untuk mengetahui pengaruh serangan S. indecora terhadap kchilangan hasil, ekobiologi, dan musuh alami, sedang kegiatan laboratorium ialah tingkat parasitasi Aphanomerus sp. pada telur S. indecora. Penelitian pengaruh serangan S. indecora terhadap kehilangan hasil jambu mete dilakukan dengan perlakuan pucuk jambu mete yang dikurung dengan kurungan kasa dan yang tidak dikurung. Perlakuan yang dikurung ialah 25 pucuk jambu mete yang tidak terserang (tanpa) S. indecora yang telah mempunyai 5-12 bunga hermaprodit. Sebagai perlakuan yang tidak dikurung ialah 13 pucuk belum terserang S. indecora dan 12 pucuk jambu mete dengan kisaran bunga hermaprodit seperti tersebut di atas yang telah terserang S. indecora. Pengamatan dilakukan terhadap perkembangan bunga mete, awal serangan pada pucuk dan berat gclondong. Untuk mengetahui sebaran 5. indecora dilakukan survei di tiga kapubaten di Propinsi NTB yaitu Lombok Barat, Lombok Timur dan Sumbawa dengan metode sampling. Penelitian biologi dilakukan terhadap 60 nimfa yang baru keluar secara individu dan diamati perkembangannya setiap hari. Penelitian untuk mengetahui musuh alami selain parasitoid telur, dilakukan pengamatan pada 10 pucuk jambu mete yang terserang 5. indecora. Pengamatan dilakukan tiap minggu. Tingkat parasitasi Aphanomerus sp. dihitung dengan mengamati parasitoid yang keluar dari 100 kelompok telur S. indecora setiap hari. Hasil penelitian di Dusun Sambik Rindang, Desa Salut, Kecamatan Kayangan, Kabupaten Lombok Barat, NTB menunjukkan bahwa serangan S. indecora menyebabkan kehilangan hasil jambu mete sebesar 57.83%. Hasil survei di tiga kabupaten yaitu Lombok Barat, Lombok Timur dan Sumbawa menunjukkan bahwa S. indecora ditemukan di tiga kabupaten tersebut. Dengan demikian 5. indecora merupakan salah satu hama utama jambu mete. Dari penelitian biologi, lama stadia telur S. indecora ialah 5-9 hari. Stadia nimfa terdiri dari 6 instar, total masa nimfa adalah 42 - 49 hari dan lama masa imago (serangga dewasa) ialah 5 -6 hai. Selain Aphanomerus sp. (Hymenoptera: Platygasteridae), beberapa musuh alami lainnya yang ditemukan di lapang yaitu laba-laba (Arachnida), kumbang Coccinellidae (Coleoptera), Braconidae, Chaleididae (Hymenoptera), belalang sembah (Orthoptera: Mantidae) dan Bocha amphilhoa (Diptera: Syrphidae). Persentase telur terparasit sebesar 9.78%. Persentase telur menjadi nimfa 8.32% dan telur yang tidak menetas 81.90%.Kata kunci : Jambu mete, bioekologi, Anacardium occidentale L , Sanurus indecora, hama, musuh alami, kehilangan hasil ABSTRACTBioecology of Sanurus indecora and the effect of its infestation on the loss of cashew yieldCashew (Anacardium occidentale L.) is an export commodity. One of the constraints in cashew production is pest attack. In West Nusa Tenggara (NTB), a latid, S. indecora had become a serious issue and was suspected as one of serious pests attacking cashew plant. Experiments to determine the bioecology of 5. indecora and the yield loss of cashew due to the insect infestation were carried out in Sambik Rindang, Salut Village. Kayangan, Lombok Barat District, West Nusa tenggara and in the laboratory of Entomology, die Indonesian Spice and Medicinal Crops Research Institute, Bogor from April to October 2003. Field activities were aimed to find out the effect of S. indecora infestation on yield loss of cashew, ecobiology, and natural enemies. Laboratory activity included parasitization stage of Aphanomerus sp. in 5. indicora. Study on the yield loss of cashew due to S. indecora was carried out by caging and uncaging shoots. Twenty two shoots with 5-12 hermaphrodite lowers were caged 13 shoots with 5-12 hermaphrodite lowers which imatially not attacked by S. indecora and 12 shoots with 5-12 hermaphrodite flowers already attacked by S. indecora. Observations were done on the development of cashew lowers, initial attack on shoots and weight of seeds. To determine the distribution of 5. indecora. a survey was conducted in three districts in West Nusa Tenggara Province namely West Lombok, East Lombok and Sumbawa, using sampling methods. Biology experiment was conducted by caging 60 newly nymphs individually on cashew seedlings and its development was observed every day. To determine natural enemies beside egg parasitoid, observation was conducted on 10 shoots attacked by S. indecora. Parasitization of Aphanomerus sp. was counted by observing natural enemies emerged from 100 egg clusters of 5. indecora. Observation was carried out once a week. Results of the experiment in Sambik Rindang, Salut Village, Kayangan, Lombok Barat District, West Nusa Tenggara showed that the latid caused 57.83% yield loss of cashew. Results of survey in three districts namely West Lombok, East Lombok and Sumbawa, showed that S. indecora was found in those three districts. Therefore, It can be concluded that 5. indecora was a serious pest of cashew plant. The biology experiment showed the duration of its eggs was 5-9 days, nymphs was 42 - 49 days, and adults was 5-6 days. The nymph consisted of six instars. Beside Aphanomerus sp. (Hymenoptera: Platygasteridae), the natural enemies found in the field were spiders (Arachnida), "lady beetle" (Coleoptera: Coccinellidae), Braco-nidae, Chaleididae (Hymenoptera), mantid (Orthoptera: Mantidae) and Bocha amphilhoa (Diptera: Syrphidae). The parasitization of Aphano-merus sp. was 9.78%. The eggs hatched to be nymphs were only 8.32% and the eggs did not hatch were 81.90%.Key words: Cashew, Anacardium occidentale L., bioecology. Sanurus indecora, pest, natural enemy, yield loss