Field trials were made in. the rainy seasons of 1970-4 at the Indian Agricultural Research Institute, New Delhi, to evaluate several systems of intercropping maize and sorghum with soya beans. Maize yields were not affected by intercropping with soya beans but sorghum yields were reduced. Though the yield of soya beans when intercropped was less than that of a sole crop, the combined grain yield of the two crops in an intercrop was more than the individual components. Land equivalent ratio (LER) increased to a maximum of about 48 and 31 % by intercropping maize and sorghum with soya beans compared with the cereal sole crops. Maize rows planted 120 cm apart and intercropped with two rows of soya beans or sorghum planted 90 cm apart intercropped with one row of soya beans proved to be the best intercropping pattern.

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In field trials made for two years in the dry period of a semi-arid tract under natural precipitation at the Indian Agricultural Research Institute, New Delhi, overnight seed-soaking of wheat in 0-5 % solution of 2-chloro-ethyl-trimethyl ammonium chloride (CCC) prior to sowing increased the grain yield. When treated with foliar application of the chemical in concentrations ranging between 40 and 1000 mg/1, wheat plots yielded better than did the untreated control, but no consistency was noted between the concentrations or stages of their application. The benefit from CCC was due to more root growth, increased stomatal resistance and higher leaf water potential. Treated plants extracted more water from deeper soil layers, increasing their water-use efficiency.

SUMMARYYields of pearl millet were significantly increased when grown after legume crops such as groundnut (22·6%), cowpea (24·2%) or pigeonpea (12·1%) instead of after pearl millet. A previous crop of short-duration mung did not affect the yield of pearl millet. Benefits from previous crops of groundnut and cowpea were equivalent to about 60 kg N/ha applied to a pearl millet crop following a previous crop of pearl millet.

SUMMARYAn experiment is desoribed which was conducted for 2 years under dryland conditions of north-west India to evaluate the optimum rate of application of N fertilizer and plant population density for a rapeseed crop. Stomata closing (phenyl mercuric acetate), film forming(Mobileaf) and reflective type (kaolinite) antitranspirants were used to examine their effectson conservation of stored moisture for a possible increased water use efficiency under drylandconditions.The rapeseed crop responded to N fertilizer and it was profitable to use 53 kg N/ha xinder these conditions. In a drier year a wider row spacing of 60 cm (1·1 x 106 plants/ ha) was significantly better than narrower spacing of 30 cm (2·2 xlO5 plants/ha). Plants grown in wider row spacings utilized less water during the vegetative and flowering stages than those grown in closer spacings.The relative water content of leaves sprayed with antitranspirants was greater than in the control plants. The leaf temperature of the kaolinite-treated canopy was 1·5 °C lower than the ambient air temperature. Averaged over 2 years, the film-forming antitranspirant Mobileaf increased the seed yield by 26% while spraying with phenyl mercuric acetate at 50 and 75 days and kaolin application at 50 days increased the rapeseed yield by 11, 18 and 17% over the no antitranspirant treatment.