KETAHANAN BEBERAPA AKSESI KAPAS TERHADAP HAMA PENGISAP DAUN Amrasca biguttula (ISHIDA)

ABSTRAK Amrasca biguttula (Ishida) adalah serangga hama pengisap daun yang sangat potensial menurunkan produktivitas kapas. Pengendaliannya secara kimiawi menimbulkan banyak masalah lingkungan, seperti pencemaran dan peningkatan resistensi hama terhadap insektisida kimia sintetis. Salah satu solusi dalam masalah tersebut adalah penggunaan varietas tahan (resisten) yang juga merupakan bagian dari pengendalian hama terpadu (PHT) pada kapas. Penelitian ketahanan beberapa aksesi kapas terhadap A. biguttula (Ishida) dilakukan di Kebun Percobaan Balai Penelitian Tanaman Tembakau dan Serat di Asembagus, Situbondo, mulai Januari hingga Desember 2006. Tujuannya adalah untuk mengetahui ketahanan beberapa aksesi kapas terhadap serangan hama pengisap daun, A. biguttula. Sebagai perlakuan adalah 30 aksesi kapas yang ditanam dalam plot berukuran 10 m x 3 m, dengan jarak tanam 100 cm x 25 cm, satu tanaman per lobang. Setiap aksesi disusun dalam rancangan acak kelompok dengan tiga kali ulangan. Parameter yang diamati adalah jumlah nimfa A. biguttula per daun, jumlah bulu daun per cm 2 luas daun, dan posisi bulu terhadap lamina (tegak/rebah), serta skor kerusakan tanaman. Hasil penelitian menunjukkan bahwa setiap aksesi kapas berpotensi terserang A. biguttula, meskipun tingkat populasi hama ini tidak menunjukkan perbedaan nyata antar aksesi. Terjadi korelasi negatif (R 2 = 0,2425) antara jumlah bulu daun dan populasi nimfa A. biguttula dan antara jumlah bulu daun dan skor kerusakan tanaman (R 2 = 0,2027). Berdasarkan jumlah bulu daun, aksesi kapas yang termasuk kategori sedikit berbulu dengan kriteria ketahanan sedikit tahan adalah: AC 134, Stoneville 7, Fai Nai, SHR, CRDI-1, Kanesia 5, Kanesia 8, dan Kanesia 9. Sedangkan aksesi lainnya termasuk kategori tidak berbulu dan peka terhadap serangan A. biguttula. Kata kunci : Kapas, Gossypium hirsutum, aksesi, hama, Amrasca biguttula (Ishida), toleran, peka, kerusakan, Jawa Timur ABSTRACT Resistance of several cotton accessions to sucking insect pest, Amrasca biguttula (Ishida) Amrasca biguttula (Ishida) is a sucking insect pest which potentially reduces cotton productivity. Its chemical control often cause environ- mental problems mainly air pollution and increase of pest resistance to certain chemical insecticides. One solution can be used to solve these problems is by using resistant variety that is also an integral part of the integrated pest management (IPM). Study on the resistance of several cotton accessions to sucking insect pest, Amrasca biguttula (Ishida) was conducted at the Experimental Station of the Indonesian Tobacco and Fiber Crops Research Institute (IToFCRI) in Asembagus, Situbondo, East Java, from January to December 2006. The objective of the study was to find out the resistance of cotton accessions to sucking insect pest. Thirty accessions of cotton were used as treatment and were planted in plots 10 m x 3 m with plant spacing 100 cm x 25 cm, one plant per hole. Each accession was arranged in a randomized block design with three replications. Parameters observed were number of nymph of A. biguttula, number of leaf hair, leaf hairs position (erect or lie down), and score of damage. The result showed that every accession of cotton can be attacked by A. biguttula although the insect population was not significantly different among accessions. There is negative correlation (R 2 = 0.2425) between number of leaf hair and population of A. biguttula and between number of leaf hair and score of plant damage (R 2 = 0.2027). Accessions that categorized as lightly hairy and moderately resistant to A. biguttula were AC 134, Stoneville 7, Fai Nai, SHR, CRDI-1, Kanesia 5, Kanesia 8, and Kanesia 9, while the others were categorized as glabrous and susceptible to the sucking pest. Key words: Cotton, Gossypium hirsutum, accession, insect pest, Amrasca biguttula (Ishida), tolerant, sensitive, damage, East Jav