Compost of dtherent rates was applied to artificial field plots of a low humic andosol at National Agriculture Research Center (NARC) of Japan for 15 or 28 years, and their effects on the chemical properties of wheat ...Compost of dtherent rates was applied to artificial field plots of a low humic andosol at National Agriculture Research Center (NARC) of Japan for 15 or 28 years, and their effects on the chemical properties of wheat rhisosphere soil and nonrhizosphere soil were measured.Continuous application of compost for 28 years resulted in raise of soil C, N, P, pH and exchangeable bases. The building up of organic matter in the soil occurred slowly A residual effect of the compost on soil chemical properties was still present after 13 years of no application, but this effect was weaker in comparison with that of the continuous application treatments. In the rhizosphere soil, NaHCO3-extracted P and exchangeable Ca were higher than those in the bulk soil. The removal of free organic acid slightly affected the soil pH, especially, the rhizosphere soil pH. The raise of soil pH may result from the increase of exchangeable base by the application of compost.展开更多
Application of inorganic fertilizers improves crop yields but costs and adverse health effects often discourage their applications. This study therefore aims at evaluating the combined effects of cassava peel compost ...Application of inorganic fertilizers improves crop yields but costs and adverse health effects often discourage their applications. This study therefore aims at evaluating the combined effects of cassava peel compost with poultry manure and mineral fertilizer on growth and yields of Corchorus olitorius. Pots （factorial laid out in a randomized complete block design） and field （split-plot with fertilizer being the main effect and the varieties the sub plot effect） experiments were carried out during rainy season at Ibadan, Nigeria. Treatments consisted of 0, 5, l0 and 20 t/ha composts prepared from cassava peel and poultry manure in ratio 3：1 and mineral fertilizer （NPK 15：15：15） at the rate of 250 kg/ha, using two varieties of C. olitorius. Five and six weeks after planting （WAP）, plants were assessed for growth and yields in pot and field experiments respectively, and also in residual studies. Application of compost significantly improved growth （heights） （36.50-41.56 cm）, while morphological and dry weight values increased with increase in compost. Marketable yield increase of 13.2%, 22.3%, 32.1% and 29.3% were recorded using 5, 10, 20 t/ha compost and NPK fertilizer respectively in the field. Corresponding increase when ratooned were 40.0%, 42.9%, 57.1% and 52.0%, respectively. Application of compost at the rate of 20 t/ha performed better in the main and residual effect experiments compared to NPK fertilizer and other compost rates. Application of cassavas peels compost at the rate of 20 t/ha proved to be adequate for optimum growth and yield performance of C. olitorius.展开更多
文摘Compost of dtherent rates was applied to artificial field plots of a low humic andosol at National Agriculture Research Center (NARC) of Japan for 15 or 28 years, and their effects on the chemical properties of wheat rhisosphere soil and nonrhizosphere soil were measured.Continuous application of compost for 28 years resulted in raise of soil C, N, P, pH and exchangeable bases. The building up of organic matter in the soil occurred slowly A residual effect of the compost on soil chemical properties was still present after 13 years of no application, but this effect was weaker in comparison with that of the continuous application treatments. In the rhizosphere soil, NaHCO3-extracted P and exchangeable Ca were higher than those in the bulk soil. The removal of free organic acid slightly affected the soil pH, especially, the rhizosphere soil pH. The raise of soil pH may result from the increase of exchangeable base by the application of compost.
文摘Application of inorganic fertilizers improves crop yields but costs and adverse health effects often discourage their applications. This study therefore aims at evaluating the combined effects of cassava peel compost with poultry manure and mineral fertilizer on growth and yields of Corchorus olitorius. Pots （factorial laid out in a randomized complete block design） and field （split-plot with fertilizer being the main effect and the varieties the sub plot effect） experiments were carried out during rainy season at Ibadan, Nigeria. Treatments consisted of 0, 5, l0 and 20 t/ha composts prepared from cassava peel and poultry manure in ratio 3：1 and mineral fertilizer （NPK 15：15：15） at the rate of 250 kg/ha, using two varieties of C. olitorius. Five and six weeks after planting （WAP）, plants were assessed for growth and yields in pot and field experiments respectively, and also in residual studies. Application of compost significantly improved growth （heights） （36.50-41.56 cm）, while morphological and dry weight values increased with increase in compost. Marketable yield increase of 13.2%, 22.3%, 32.1% and 29.3% were recorded using 5, 10, 20 t/ha compost and NPK fertilizer respectively in the field. Corresponding increase when ratooned were 40.0%, 42.9%, 57.1% and 52.0%, respectively. Application of compost at the rate of 20 t/ha performed better in the main and residual effect experiments compared to NPK fertilizer and other compost rates. Application of cassavas peels compost at the rate of 20 t/ha proved to be adequate for optimum growth and yield performance of C. olitorius.
