Pengaruh Waktu Pemberian dan Dosis Amelioran Abu Janjang Kelapa Sawit terhadap Pertumbuhan dan Hasil Kedelai (Glycine max (L). Merrill ) di Tanah Gambut Palangka Raya
Soybean is the most important food commodity besides rice and maize. Besides from being a source of vegetable protein, soybean is used as animal feed and raw material for processing industrial of soy sauce and soymilk. Land in Palangka Raya is peat soil that mostly high level of acidity. This constraint for agriculture development because of low availability of plant nutrients. One attempt to overcome this obstacle is the application of oil palm bunch ash (OPBA).The aim of this study was to analyse the interaction between the time application and doses of OPBA on the growth and yield of soybean in peat soil. The research was conducted on peat soil in the Bereng Bengkel village, Sebangau subDistrict, Palangka Raya using randomised block design (RBD) with two factorialtreatments. The first factor is the timing of OPBA application which consists of two levels i.e., two weeks before planting (WBP) and tree WBP planting. The second factor is the OPBA dosage which consists of four levels i.e., without OPBA, 250 kg/ha, 500 kg/ha and 750 kg/ha. Each treatment was repeated three times so that there were 24 experimental units. The experimental results showed the interaction time of timing and OPBA dosage on peat soil was highly significant; the number ofeffective root nodules on five weeks after planting (WAP) observation. The single factor of OPBA application time has very significant effect on a number of effective root nodules age five WAP, days to flowering and number of pods per plant. While single-dosage factor OPBA has very significant effect on the number of root nodules on five WAP observation, broad leaf age nine WAP, days to flowering and number of pods per plant