Respond of yield, yield components and water use efficiency of some fennel (Foeniculum vulgare L.) ecotypes in irrigation regimes and folia application of humic acid

The study was carried out to assess the effects of humic acid and irrigation cut on yield, yield component and water use efficiency of three fennel ecotypes (Foeniculum vulgare L.) at the reproductive stages. The study was carried out in Agriculture and Natural Resources Science University of Khuzestan in a factorial split plot based on randomized complete block design with three replications during 2016-2017. Irrigation regimes (complete irrigation, irrigation cut from flowering stage, irrigation cut from grain filling stage) and foliar application of humic acid (no application and foliar application of 400 mg.l-1) were placed in main plots by a factorial arrangement, and three ecotypes (Isfahan, Hamadan, Bushehr) were placed in sub plots. The results showed that the highest plant height (157.86 cm) was obtained from complete irrigation and Esfahan ecotype (153.6 cm). The highest number of sub branches (10.14) was obtained by foliar application of humic acid and Esfahan ecotype (10.16). The irrigation cut from flowering stage caused reduced thousand grain weight. The highest umbel per umbrella (24.52), grain yield (1876.95 kg.ha-1) and irrigation efficiency (531.99 grams per cubic meter) were obtained under complete irrigation with foliar application of humic acid. The highest number of umbrella was obtained from Bushehr ectype under complete irrigation conditions. Generally, Bushehr ecotype with complete irrigation and foliar application of humic acid is recommended in terms of higher grain yield, yield components and irrigation efficiency.