Nutrient harvest and soil fertility as influenced by nutrient management in rice (Oryza sativa) forage crop sequences

Abstract

The field experiment was conducted at Ranchi to study the effect of integrated nutrient management on nutrient removal and soil fertility under rice (Oryza sativa L.) forage crop sequences during 1997 2000. The pooled results indicated that the rice as a succeeding crop to berseem (Trifolium alexandrinum) and higher yield when both the crops were grown at 75% recommended level of NPK 10 tonnes FYMJha. Application of 75% recommended level of NPK 10 tonnes FYMIha in both the seasons also recorded the maximum forage yield in oat (Avena sativa L.), followed by the oats forage harvested at 100% recommended level of NPWha (40 kg N 8 kg P 6 kg K for upland rice, 25 kg N 24 kg P 24 kg K for berseem and 100 kg N 16 kg P 24 kg K for oat) applied through fertilizers only. Alike oat forage, berseem also gave the maximum forage yield under the same fertility treatment. Rice harvested after berseem removed higher quantity of NPK them rice harvested after oat. Among forage components, berseem gave higher NPK yield than oat, while rice berseem sequence as a whole removed the maximum quantity of NPK. The balance sheet of nutrients further indicated maximum recovery of these nutrients under cereal cereal sequence compared to cereal legume. A definite enhance ment in N and P status of soil to its initial level was noticed but the trend was reversed in case of K build up which indicatedsome additional application of K in these crops. ,