Indian Journal of Fundamental and Applied Life Sciences ISSN: 2231-6345 (Online) An Open Access, Online International Journal Available at http://www.cibtech.org/jls.htm 2014 Vol. 4 (3) July-September, pp. 50-54/Khalilvand and Herischi. Research Article © Copyright 2014 | Centre for Info Bio Technology (CIBTech) 50 EFFECT OF METHANOL FOLIAR APPLICATION ON SUNFLOWER (HELIANTHUS ANNUUS L.) PERFORMANCE UNDER DIFFERENT REGIMES OF IRRIGATION *Ebrahim Khalilvand Behrouzyar and Mojhgan Herischi Department of Agronomy and Plant Breeding, College of Agriculture and Natural resources, Tabriz Branch, Islamic Azad University, Tabriz, Iran *Author for Correspondence ABSTRACT In order to evaluate the effect of methanol foliar application on sunflower (Helianthus annuus L.) performance under different regimes of irrigation, an experiment was conducted in the split plot form based on Completely Randomized Block Design with three replications during growing seasons of 2011- 2012. Treatments were water deficit stress in four levels: a 1 : severe stress (25% FC irrigation), a 2 : mild stress (50% FC irrigation), a 3 : fair stress (75% FC irrigation) and a 4 : normal irrigation (100% FC irrigation) and the foliar application of methanol in six levels [b 1 :0, b 2 :7, b 3 :14, b 4 :21, b 5 :28 and b 6 :35 (v/v)]. The analysis of variance showed significant effect of interaction between water deficit stress and methanol foliar application on oil yield per plant, dry weight per unit area, Full and empty seeds percentage (p<0.01). 21% (v/v) Methanol foliar application and normal irrigation produced 69% more oil yield per plant, 2/4 times more dry weight. Besides, the results also proved that 21% (v/v) methanol foliar application in 100% FC had the lowest empty seeds percentage (4/07%). Furthermore, the highest full seeds percentage (95/92) was observed for 7% (v/v) methanol and normal irrigation. Keywords: Methanol, Sunflower, Water Deficit Stress INTRODUCTION Water deficit is a major environmental factor restricting plant growth, development and productivity, particularly in arid regions more than any other single environmental factor (Huai-Fu et al., 2014). Water stress reduces photosynthesis via reduction in leaf area, closing stomata and reduction of carbon fixation efficiency (Abbasi et al., 2014). Photosynthesis is the substantial process for the production of organic matter in plants (Andres et al., 1989). Usually, the amount of the produced dry matter has a direct relationship with the photosynthesis efficiency of the plant and also the way in which CO2 fixation occurs in crops. Today, in order to achieve this goal, compounds such as methanol, ethanol, propanol, butanol and amino acids like glycine, glutamate and asparate are used. Recent investigation showed that C 3 crops yield and growth increased via methanol spray and methanol may act as C source for these crops. Therefore, Methanol spray is a method which increases crop CO 2 fixation in unit area (Hemming and Criddle, 1995). Sadeghi-Shoae et al., (2014) reported that methanol foliar application enhanced total dry matter (TDM), root yield (RY), sugar yield (SY) and white yield sugar. Thus, methanol spraying results in increased production and reduces plants' water requirement in warm and dry conditions (Aslani et al., 2011). Spraying with 25% volume level significantly increased in plant height, number of lateral root, root dry weight, tap root length, root area, root area to leaf area ratio, total root length, root to shoot ratio and leaf area compared with control (Hossinzadeh et al., 2012). Positive effects of methanol foliar application on growth of other plant have been confirmed in previous studies. Thus, the objectives of this study were to investigate the effects of methanol foliar application on sunflower performance under different regimes of irrigation.