Effect of hardening time and nutrient concentration of media by in-vitro on growth of oil palm (Elaeis guineensis Jacq.) plantlet at prenursery

English. The experiment was aimed at finding out the effective hardening time and nutrient concentration of media to support the optimal growth of oil palm plantlet at prenursery. The experiment was carried out in August 1996 to January 1997 at Tissue Culture Laboratory of Oilpalm Research Center, Marihat, Pematang Siantar. The experiment was arranged in split-split-plot design with three replications. The treatments were hardening time (one and two months), root quality (A, B, and C) and nutrient concentration (25 percent, 50 percent, and 75 percent MS). The results showed that two months hardening increased root and crown quality, but percent live of oilpalm plantlet were lower than in one month. Plantlet with A root quality showed better root and crown quality, and percent live than B and C root quality, crown quality, and percent live were better than those at 25 percent and 50 percent MS

Indonesian. Penelitian ini bertujuan untuk mengetahui waktu hardening dan konsentrasi hara media yang efektif untuk meningkatkan daya hidup planlet kelapa sawit di prenursery. Penelitian dilaksanakan pada Agustus 1996 sampai Januari 1997 di laboratorium Kultur Jaringan Pusat Penelitian Kelapa Sawit, Marihat, Pematang Siantar. Penelitian menggunakan rancangan petak terpisah-pisah dengan tiga ulangan. Perlakuan yang dicobakan terdiri dari: lama hardening (satu dan dua bulan); mutu akar (A, B, dan C), serta konsentrasi hara dalam media (25 persen, 50 persen, dan 75 persen MS). Hasil penelitian menunjukkan bahwa lama hardening dua bulan menghasilkan kualitas akar dan tajuk yang lebih baik daripada lama hardening satu bulan, tetapi persentase hidup planlet kelapa sawit lebih rendah. Mutu akar A menghasilkan kualitas akar dan tajuk yang lebih baik serta persentase hidup yang lebih tinggi daripada mutu akar B dan C. Konsentrasi hara 75 persen MS menghasilkan kualitas akar dan tajuk yang lebih baik serta persentase hidup lebih tinggi daripada konsentrasi hara 25 persen dan 50 persen MS