GALUR-GALUR HARAPAN KAPAS DI LAHAN TADAH HUJAN
Authors: SUMARTINI SIWI , ABDURRAKHMAN ABDURRAKHMAN , SULISTYOWATI EMY 
Published: June 2020

ABSTRAK<br />Areal pertanaman kapas di Indonesia tersebar di enam propinsi yaitu<br />Jawa Tengah, Jawa Timur, Bali, Nusa Tenggara Barat, Nusa Tenggara<br />Timur, dan Sulawesi Selatan. Pengembangan kapas 70% berada di lahan<br />tadah hujan dan 30% di lahan sawah sesudah tanaman padi. Di lahan tadah<br />hujan biasanya kapas ditanam setelah jagung, kedelai atau kacang hijau<br />dan selalu mengalami kendala kekurangan air selama pertumbuhannya.<br />Karena kendala tersebut, produksi kapas berbiji ditingkat petani umumnya<br />hanya mencapai 200 – 500 kg per hektar. Penelitian uji multilokasi<br />dilaksanakan di Asembagus dan Wongsorejo (Jawa Timur), Bayan (Nusa<br />Tenggara Barat), dan Bantaeng serta Bulukumba (Sulawesi Selatan), di<br />lahan tadah hujan pada tahun 2004 – 2006. Sebanyak 9 galur dan varietas<br />Kanesia 8 disusun dalam rancangan acak kelompok yang diulang 4 kali<br />(tiga ulangan tidak mendapatkan tambahan pengairan setelah tanaman<br />berumur 42 hari atau setelah pemupukan kedua), satu ulangan diberi<br />pengairan optimal sampai panen, yang digunakan untuk menghitung<br />Indeks Kepekaan Terhadap Kekeringan. Kapas ditanam secara monokultur<br />pada petak percobaan berukuran 50m 2 dengan jarak tanam 100 cm x 25<br />cm, satu tanaman per lubang. Pengamatan yang dilakukan adalah : hasil<br />kapas berbiji pada kondisi keterbatasan air, hasil kapas berbiji pada<br />kondisi pengairan optimal, indeks kerentanan terhadap kekeringan, skor<br />kerusakan daun akibat serangan Amrasca biguttula, dan mutu serat. Pada<br />kondisi tidak mendapatkan tambahan pengairan, rata-rata potensi hasil<br />galur-galur yang diuji tidak berbeda nyata dengan varietas Kanesia 8 serta<br />toleran terhadap A biguttula dan mutu seratnya memenuhi syarat untuk<br />industri tekstil di Indonesia. Galur-galur yang produktivitasnya mencapai<br />lebih dari 1.500 kg kapas berbiji/ha adalah (135x182)(351x268)9,<br />(135x182)(351x268)10, dan (135x182)10. Dilihat dari produktivitas, keta-<br />hanan terhadap A. biguttula, ketahanan terhadap kekeringan dan mutu<br />serat, terdapat dua galur harapan yang dapat dilepas sebagai varietas baru<br />yang sesuai untuk dikembangkan di lahan tadah hujan pada kondisi keter-<br />batasan air yaitu galur {(135x182)(351x268)}9 dan galur (339x448)2.<br />Keunggulan galur {(135x182)(351x268)}9 adalah lebih toleran terhadap<br />kondisi dengan ketersediaan air terbatas dibandingkan dengan Kanesia 8,<br />sedangkan produktivitas, ketahanannya terhadap A biguttula, serta mutu<br />seratnya tidak berbeda. Keunggulan galur (339x448)2 dibandingkan<br />dengan Kanesia 8 adalah mutu seratnya lebih tinggi, sedangkan produk-<br />tivitas serta ketahanannya terhadap keterbatasan air dan A. biguttula tidak<br />berbeda.<br />Kata kunci : Kapas, produktivitas, mutu serat, tahan terhadap kekeringan<br />ABSTRACT<br />New cotton lines adaptive to rain-fed<br />Cotton growing area in Indonesia extended in six provinces i.e.<br />East Java, Middle Java, Bali, West Nusa Tenggara, East Nusa Tenggara<br />and South Sulawesi. Cotton area in Indonesia is mostly (70%) in rain-<br />fed, and the rest is on rice-field after paddy (30%). On rain-fed areas,<br />cotton is commonly grown after maize, soybean, or greenbean, that it<br />suffers from drought. This condition has resulted low yield ranging 200 –<br />500 kg seed cotton per hectare. As a result, farmers income and farmers<br />interest in cotton cultivation are low . Multilocations trial were conducted<br />in Asembagus and Wongsorejo (East Java), Bayan (West Nusa Tenggara),<br />and Bantaeng as well as Bulukumba (South Sulawesi), on rain-fed area in<br />2004 to 2006. 9 lines of cotton and Kanesia 8 were arranged in randomized<br />block design with four replications three replications without irrigation 42<br />days after planting and one replication with optimal irrigation for the<br />estimation of drought susceptibility index. Monoculture cotton was grown<br />in plots sized 50 m 2 with 100 cm x 25 cm plant spacing, one plant per<br />hole. Parameters observed were seed cotton yield on water limited<br />condition, seed cotton yield on full irrigation, drought susceptibility index,<br />score of leaf damage caused by Amrasca biguttula, and fibre quality.<br />Means of productivity level of the cotton lines on water limited condition<br />were not significantly different to Kanesia 8, all of them were tolerant to<br />A biguttula with fiber quality was suitable for textile industries in<br />Indonesia. There were three lines reached productivity more than 1,500<br />kg/ha i.e. (135x182)(351x268)9, (135x182) (351x268)10, and (135x<br />182)10. From the trials, there were two promising lines i.e. lines<br />(135x182) (351x268) 9 and (339x448) 2 which can be released as new<br />varieties tolerant to water limited condition. Lines (135x182)(351x268) 9<br />was more tolerant to water limited condition than Kanesia 8, and it was not<br />significantly different in productivity, tolerancy to A biguttula, and fibre<br />quality. Lines (339x448)2 was superior on its fiber quality than Kanesia 8<br />and its productivity as well as its tolerancy to water limited condition and<br />A biguttula were not significantly different.