Yoyo Soelaeman and Umi Haryati
Acid upland soil in Indonesia has a great potential for agricultural development but the soil physical properties have been degraded. The use of manure and direct application of Gresik phosphate rock (PR) was an alternative to improve land productivity and crop yields. The objective of the study was to evaluate the effects of manure and P sources on soil physical properties and yield of food crops, which was arranged on intensive cropping systems of upland rice + maize -/- cassava- mungbean. The experiment was carried out in Tamanbogo Research Farm, East Lampung from 2007 to 2009 using randomized complete block design with 3 replications. The treatments were (1). 10 t ha-1 manures+1 ton per ha of PR, (2). Without manure + 1 ton per ha of PR, (3). 10 ton per ha manures+100 kg per ha of SP 36, and (4). Without manure+100 kg per ha of SP 36. The results showed that the application of manure along with PR improved soil physical characteristics of ultisol soil and gave the highest yield of food crops with B/C in year 3th was 3.60.
Keywords: soil physical property, manure, P fertilezation, upland ultisol, Lampung