Technical and economical assessment of the effect of micro and furrow irrigation methods on grain yield and water use efficiency in four rapeseed cultivars

To select the suitable irrigation metod and oil rapeseed cultivar with high seed yield and oil content, a field experiment was carried out using a split plot arrangement in randomized block design with three replications in Hamedan in 2005-2006 grwoing seasons. Irrigation methods, tape and furrow irrigation, were assigned to mainplots cultivars, Opera, Licord, SLM046 and Okapi, were randomized in sub-plots. Results showed no significant differences in the grain yield of cultivars. Irrigation×cultivar intraction was significant (P 0.05). The highest seed yield (3961 Kg.ha-1) was obtained from cv. Opera with tape irrigation method and cv. SLM046 produced the least seed yield of 3710 Kg.ha-1 in furrow irrigation method. The average water use efficiency in tape and furrow irrigation was 1.34 kg.m3 and 0.74 kg.m3, respectively. The average of water use in furrow and tape irrigation methods was 2617 m3.ha-1 and 4870 m3.ha-1, respectively. Tape and furrow irrigation methods had similar seed yield, but water use in tape irrigation method was reduced by about 46%. However, despite of reduction water use in tape irrigation method, the cost of irrigation increased and net revenue decreased by about 1,329,480 Iranian Rails. Benefit:cost ratio indicated that tape irrigation method was not economical for oil rapeseed production.