Influence of Foliar Applied Nitrogen on Reproductive Growth of Sunflower (<i>Helianthus annuus</i> L.) under Water Stress

Abstract

Nitrogen is a major nutrient involved in plant growth and yield. Plants cannot get the nutrients from the soil medium under water stress condition to testify foliar application in stress condition to fulfil plant need for better performance. In this regard, a field study was conducted to evaluate the effect of foliar-applied nitrogen (0, water and 1% urea) on sunflower (cv. Hysun-33) under normal and water stress at reproductive stage. Two soil applied nitrogen levels control (0 kg · ha -1 ) and recommended dose (115 kg · ha -1 ). Supplemental foliar application of nitrogen in the form of urea significantly increased the growth, yield and yield components of sunflower under water stress. The increase in yield with 1% urea spray was recorded up to 1.37 t · ha -1 in comparison to water spray (1.07 t · ha -1 ) and no spray (1.00 t · ha -1 ). While maximum values of all factors were obtained where 1% urea spray with soil applied nitrogen was used in both stresses as well as in non-stress condition. Therefore, reasonable yield can be achieved by applying foliar application of urea (1%) as a supplemental source to soil applied nitrogen under water stress.