EFFECTS OF IRRIGATION HALT ON YIELD AND YIELD COMPONENTS OF THREE SUNFLOWERS (Helianthus annuus L.) CULTIVARS IN IRANIAN SEMI-ARID ENVIRONMENT
Published in AgroLife Scientific Journal, Volume 3, Number 1
Written by Hamid MADANI, Amir SHARIFI
In order to study the growth and development of three irrigated sunflower hybrids (Helianthus annuus L. CVs. Zaria, Alestar and Azargol) in different irrigation halts, a field experiment was conducted at Zahedan Islamic Azad University field experiments Zahedan, Iran, in 2005. The experiment was laid out in split plot arrangement at randomized complete block design (RCBD) in 4 replications. Main plots were arranged for irrigation halt according to plant phonological stages in four levels normal irrigation or control, halt irrigation at pre anthesis, full flowering and post anthesis stages, sub plots were included three sunflower Zaria, Alestar and Azargol cultivars. The results showed halt irrigation had significant effect on all measured characters. The study of treatments interactions showed halt irrigation could reduce sunflower yield quality and quantity immediately. Azargol hybrid under flowering stage halt irrigation had the heist seed yield by 4.29 t/ha. However, Azagol cultivar was able to maintain its yield by 4.3 t/ha after halt irrigation at seed development stage. Alestar cultivar was more sensitive to halt irrigation at reproductive stages; its decreased was 48% and 45% in yield and oil yield, respectively. Zaria cultivar showed higher resistance to halt irrigation, comparing to Alestar and Azargol.