Sustainability of different crop sequences with special reference to nutrient utilization
2002
Pascua, S.R. | Valencia, D.A. (Mariano Marcos State Univ., Batac, Ilocos Norte (Philippines)) Padre, A.T. | Marcos, T.F. | Obien, S.R.
A long-term field trial was conducted to determine the effect of intensified cropping and fertilizer application on the nutrient status of the soil and crop yield and to find out the influence of crop residue addition to the yield of rice. There were 5 levels of N applied to rice (0, 30, 60, 90, 120 kg/ha) and 5 cropping systems such as rice-corn-mungbean, rice-mungbean-corn, rice-garlic-mungbean, rice-sweet pepper-corn, and rice-tomato-corn applied with and without the recommended rates of fertilizer for each main dry season (DS) crops. Relay crops were not fertilized. A 90 and 120 kg N/ha applied produced an average yield of 3.88 and 4.28 t/ha, respectively. Crop residue added increase rice grain yield from 0.4 to 0.6 t/ha specifically to fertilized DS crops. Fertilizer applied to the main DS crops has a residual effect increasing rice grain yield from 0.4 to 0.9 t/ha in a rice-sweetpepper-corn, rice-tomato-corn and rice-garlic-mungbean systems. Dry season crops applied with the recommended rate of fertilizer significantly produced higher yield except for mungbean. Furthermore, fertilized plots can still produce glutinous green corn ranging from 0.14 to 5.31 t/ha and 0.54 to 4.42 t/ha when planted as relay to sweet pepper and tomato, respectively. Rice-corn-mungbean system has a higher soil N, 0.113% than rice-mungbean-corn, 0.104%. In 1999, plots applied with the recommended rate of fertilizer shows a higher carbon content, 1.39% than the unfertilized plot, 1.35%. Rice-garlic-mungbean system contributed significantly with mean equivalent K value of 258 kg/ha/yr or 10 bags of KCI
显示更多 [+] 显示较少 [-]