Effect of mulches and transpiration suppressants on yield, water use efficiency and uptake of nitrogen and phosphorus by sorghum under dryland conditions of north-western India
SUMMARYField experiments consisting of three mulch treatments (no mulch, straw mulch and dust mulch) and six transpiration suppressants (no suppressant, kaolin, phenyl mercuric acetate, atrazine, mobileaf or alachlor and 2-chloro ethyl trimethyl ammonium chloride) were conducted under dryland conditions during the summer rainy seasons (July–November) of 1976, 1977 and 1978. Compared with no mulch, straw mulch increased yield in all 3 years, water use efficiency in 1977 and 1978, and uptake of N and of P in 1977 and 1978. Dust mulch had only a marginal advantage. Amongst transpiration suppressants, only kaolin and atrazine had a marked effect. Both these chemicals increased grain yield, water use efficiency and uptake of N and P, compared with no suppressant.