STABILITY ANALYSIS OF RICE (ORYZA SATIVA): WHEAT (TRITICUM AESTIVUM) CROPPING SYSTEM IN INTEGRATED NUTRIENT MANAGEMENT

An experiment was conducted on integrated nutrient supply system.in rice (Oryza sativa L.)-wheat (Triticum aestivuw L.emend, Fiori & Paol.) cropping sequence at 5 centres since 1983-91 showed that 50% recommended NPk+ 50% through crop residue in rice followep. by 100% NPK in wheat could stabilize yields of rice and wheat at Kanpur. whereas 50% N need of rice can be substituted by farmyard manure, followed by 100% NPK in wheat at Ludhiana, At Jabalpur the 50% recommended NPK + 50% through green-manuring could stabilize yields of both the crops, whereas at Masodha, yields of rice and wheat were stabilized when 50% recommended NPK was used in conjunction with 50% recommended crop residues, At Kalyani, 75% recommended NPK + 25% by green-manuring in rainy (kharif) season followed by 75% recommended NPK in winter (rabi) season could stabilize yields of rice and wheat and save 25% N fertilizer in winter season. The continuous rice-wheat cropping increased the organic carbon status at Masodha and Kanpur increased whereas it remained same at Jablapur, It also increased available P and K at Masodha and Kanpur However, at Jabalpur decreasted in available P and increase in K was observed. Integrated nutrient supply had favourable effect on' organic carbon status and available P and K at all the centres except P at Jablapur.