determining the water productivity components under planting single irrigation management for rainfed wheat varieties

the main purpose of rainfed farming is increasing the water productivity by applying suitable agricultural management including single irrigation (si) and panting time for wheat varieties. in order to study the si optimization and determination its optimal program, a field experiment was conducted as split-split plot based on a randomized complete block design with three replications for different wheat varieties at main station of dryland agricultural research institute (dari), maragheh, iran, during two crop seasons of 2000-2004. the treatments included three panting time, three si and five wheat varieties (v1=72yrrgp, v2=fenkang 15/sefid (seed white), v3=turkey, 13//f9.10/maya”s”, v4=azar2, v5=double cross shahi). on based of water productivity indices, rain water productivity (rwp), irrigation water productivity (iwp), and total water productivity (twp) optimal program of single irrigation scenarios was 100mm at early, 75mm at normal and 50mm at late sowing date. v3 wheat variety was better than other varieties. at this single irrigation program, maximum single irrigation water productivity (11.3 – 21.3 kg.mm-1) in producing grain yield and stabilized wheat production were obtained