Adisu Tadese*, Lema Teklu
Alternate furrow irrigation with proper irrigation intervals could save irrigation water and result in high yield with minimum irrigation water and costs during dry season. Field experiment was conducted at two locations for two consecutive years to investigate the effect of alternate furrow irrigation with irrigation intervals (AFI with normal, reduced and extended irrigation intervals) on yield, water productivity and economic return of maize as compared with every-furrow irrigation (EFI, conventional method with normal irrigation interval). Normal irrigation interval is irrigation interval produced by CROPWAT model. Results indicated that highest green cob yield 10733/ha and 10822/ha at Diga and 10044/ha and 10200/ha were obtained from AFI with normal irrigation interval treatment during two consecutive seasons whereas, low number are collected from Farmer practice (FP) treatments. However, highest water productivity (WP) values (3.42 kg/m3, 3.45 kg/m3,3.55 kg/m3 and 3.30 kg/m3) were observed from AFI with extended irrigation interval at both locations during consecutive growing seasons. Irrigation water saved at Wayu Tuka under AFInorm and AFIextended treatments were approximately 50% and 60% respectively, as compared to the CFI treatment and 43.6 and 55.7% AFInorm and AFIextended treatments respectively at Diga site. However, under AFIextended yield reduction was observed as compared with AFInorm. It could be concluded that Alternate-furrow irrigation with normal irrigation interval can improve crop water productivity without the risk of yield reduction. Therefore, if low cost water is available and excess water delivery to the field does not require any additional expense, then the AFI normal irrigation interval treatment will essentially be the best choice under the study area conditions [1].