Productivity and water use efficiency of niger (Guizotia abyssinica) genotypes under different dates of sowing

A field experiment was conducted for 3 consecutive years from 1989 to 1991 to find out the effect of sowing time on productivity and water use efficie ncy of niger (Guizotia abyssinica Coss.) genotypes. 'GA 10' produced the hi ghest seed yield of 497.4 kg/ha which was 3.8 and 21.3% more over 'IGP 76' and 'UN 4', respectively The crop sown on 20 August recorded higher yield ( 571.9 kg seed/ha) than earlier or later sown crops. The moisture use effici ency was maximum for 'GA 10' (16.08 kg seed/ha/mm and 98.5 kg total yield/h a/mm. Sowing of the crop on 20 August proved efficient in utilizing soil mo isture towards seed yield (19.78 kg/ha/mm) while 21 July sown crop resulted in the highest water use proved efficiency for total biomass yield (117.27 kg/ha/mm). 'GA 10' showed the maximum moisture use efficiency for its seed yield when sown on 20 August.