Effect of irrigation and antitranspirant on biometric components, seed yield and plant water-use of spring sunflower (Helianthus annuus)

A field experiment was conducted during the spring seasons of 1999 and 2000 to study the effect of 5 irrigation levels and 4 antitranspirant treatments on sunflower (Helianthus annuus L.) at Hisar, Haryana. Scheduling of 4 irrigations (l₄), one each at seedling, button, flowering and seed-developing stage recorded significantly higher growth and yield attributes, and seed yield (pooled 19.71 q/ha) of sunflower. Cumulative water use, water-use efficiency, leaf water potential and transpiration rate as plant water-use parameters and average net return (Rs 8,031/ha) were also maximum with l₄ treatment. Effect of antitranspirants, as an irrigation saving technique in semi-arid situation, however, was not satisfactory. Interaction between irrigation levels and antitranspirants on any of the parameters was observed non-significant.