Diversification of existing rice (Oryza sativa)-based cropping system for sustain- able productivity under irrigated conditions

A field experiment was conducted during 1998-99 and 1999-2000 at Palampur, to diversify existing rice (Oryza sativa L.)-wheat (Triticum aestivum L. emend. Fiori & Paol.) cropping system. Wheat in rice-wheat sequence was replaced with 1 or 2 crops of oilseeds or vegetables crops, viz. gobhi sarson (Brassica napus ssp oleifera DC var. annua L.), linseed (Linum usitatissimum L.), toria [Brassica campestris L. ssp. oleifera (Metzger) Sinsk. var. toria] potato (Solanum tuberosum L.), pea (Pisum sativum L.) and Frenchbean (Phaseolus vulgaris L.). Rice-pea-po- tat0 sequence recorded significantly highest rice-equivalent yield with production efficiency as high as 58.38 kg/ hdday. However, rice-pea-Frenchbean gave an additional net returns of Rs 7,1101ha over rice-pea-potato, which were also highest than that of rice-wheat. Land-use efficiency as well as benefit : cost ratio were also highest in rice-pea-Frenchbean. Thus in rice-wheat system, wheat crop can be safely replaced by pea, which can be fol- lowed either by potato or Frenchbean.