PENGARUH BAHAN ORGANIK DAN PUPUK NPK TERHADAP HASIL SERAT ROSELA DI LAHAN PODSOLIK MERAH KUNING KALIMANTAN SELATAN

Abstract

ABSTRAK Lahan podsolik merah kuning (PMK) berpotensi untuk pengem- bangan tanaman rosela. Kendala utama dalam lahan PMK adalah miskin unsur hara makro dan mikro, kandungan Al dan Fe tinggi, pH tanah rendah dan sering terjadi fiksasi P. Daya dukung lahan ini dapat diperbaiki dengan memberikan bahan amelioran seperti kapur atau bahan organik. Penelitian dilaksanakan di Desa Sabuhur II, Kecamatan Jorong, Kabupaten Tanah Laut, Kalimantan Selatan pada bulan Januari sampai dengan Desember 2001. Perlakuan disusun dalam rancangan petak terbagi yang diulang tiga kali. Sebagai petak utama terdiri atas lima jenis bahan organik, yakni (1) pupuk kandang kotoran ternak sapi, (2) pupuk kandang dari kotoran unggas, (3) kompos dari jerami, (4) kompos dari alang-alang, dan (5) kompos dari serpihan kayu rosela, masing-masing dosisnya 5 t/ha. Anak petak terdiri atas tiga dosis pupuk anorganik yaitu (A) Tanpa pupuk anorganik, (B) (45 kg N + 80 kg P 2 O 5  + 60 kg K 2 O) /ha, dan (C) (90 kg N + 80 kg P 2 O 5  (fosfat alam) + 60 kg K 2 O) /ha. Bahan tanaman yang digunakan galur rosela CPI 115357. Ukuran petak 4 m x 6 m dengan jarak tanam 20 cm x 20 cm. Tujuan dari penelitian ini adalah untuk mendapatkan jenis bahan organik dan dosis pupuk anorganik (NPK) yang dapat mendukung hasil serat rosela yang tinggi di lahan PMK Kalimantan Selatan. Hasil penelitian menunjukkan, bahwa kombinasi perlakuan pemberian (5 t pupuk kotoran unggas + 45 kg N + 80 kg P 2 O 5  (fosfat alam) + 60 kg K 2 O) /ha memberikan pertumbuhan tinggi tanaman, diameter batang, hasil brangkasan dan hasil serat kering tertinggi rosela masing- masing 262,33 mm; 17,65 mm; 47,78 t dan 2,83 t/ha. Kata kunci : Rosela, Hibiscus sabdarifa L., podsolik merah kuning, bahan organik, pupuk organik, hasil, Kalimantan Selatan ABSTRACT Effect of NPK fertilizer and organic materials on rosella fiber yield in red yellow podzolic soil of South Kalimantan Red yellow podzolic soil is potential for rosella development. The major problem of red yellow podzolic soil is low fertility of soil, especially macro and micro elements, high content of Al and Fe and P fixation often happened. The soil capacity can be improved by application of ameliorant materials such as lime or organic materials. The experiment was conducted in Sabuhur II Village, Jorong Sub District, Tanah Laut District in South Kalimantan during growing season of January to December 2001. The experiment was designed in split-plot with three replications. The main plots were source of organic materials (1) cows manures, (2) chicken manures, (3) compost of rice hays, (4) compost of alang-alang, and (5) compost of rosella stems with dose 5 t/ha respectively. The sub plots were the dosage of NPK fertilizer (A) zero fertilizer, (B) 45 kg N + 80 kg P 2 O 5  + 60 kg K 2 O /ha, and (C) 90 kg N + 80 kg K 2 O 5  + 60 kg K 2 O/ ha. The rosella clone was CPI 115357 line, plot size 4 m x 6 m, and plant spacing 20 cm x 20 cm. The purpose of this experiment was to find out the kind of organic materials and dosage of unorganic fertilizer which can support rosella fiber yield in red yellow podzolic soil of South Kalimantan. The result showed that the application of 5 tons chicken manures + 45 kg N + 80 kg P 2 O 5 (rock phosphate) + 60 kg K 2 O/ha gave the best plant height, stem diameter, fresh and dry fiber yield of rosella which were 262,33 cm; 17,65 mm; 47,76 tons and 2,83 tons respectively. Key words : Rosella, Hibiscus sabdarifa L., red yellow podzolic, organic materials, unorganic fertilizer, yield, South Kalimantan