Effects of Methanol on Sugar Beet (Beta Vulgaris)‪.‬

Introduction Production of biomass by plants depends to great extent on environmental factors such as water supply, air temperature and carbon dioxide concentration in the canopy (Zbiec et al., 2003). Numerous experiment have shown that by increasing the dioxide carbon content in air, the crops yield increased and plants accumulated more carbohydrates because almost 90% of plant dry weight is resulted from C[O.sub.2] assimilation during photosynthesis (Abdel-Latif et al., 1996). Methanol spry is a method which increases crop C[O.sub.2] fixation in unit area. Recent investigation showed that [C.sub.3] crops yield and growth increased via methanol spray and methanol may act as C source for these crops (Makhdum et al., 2002). Abundant dioxide carbon supply from methanol causes the photorespiration to be shifted from catabolism to anabolism (Zbiec et al., 1999). Photo respiration can be minimized with methanol spray, since 25% of carbon wastes during photorespiration (Desclaux et al., 2000). That is because methanol is absorbed in plant and rapidly metabolized to C[O.sub.2] in plant tissue due to smaller size of methanol rather than C[O.sub.2] (Gout et al., 2000). The major source of methanol production in plant is cellular pectin demethylation . Such volatile organic compound i.e., methanol exist leaves via stomata and it is obvious that plant tissues metabolize methanol (Galbally et al., 2002). A small proportion of this endogenous methanol reaches leaf surfaces, where it is volatilized or consumed by methylotrophic bacteria. These bacteria are capable to grow on methanol and generate plant growth regulators such as auxin and cytokinin (Lee et al., 2006). Also these bacteria are associated with nitrogen metabolism in plants through production of bacterial urea (Fall et al., 1996). Glycine has effective roll in drought stress and other stress induced physiological response (Zbiec et al., 2003). Only [C.sub.3] plants which produce ribolose 1,5-diphosphate and then 3phosphoglyceric acid during their photosynthetic carboxylation respond to methanol by increased biomass production, since carbon dioxide resulting from rapid oxidation of methanol can successfully compete with oxygen for RuBisco (Ramirez et al., 2006). Foliar application of methanol can increase the activity of nitrate reductase and alkaline phosphatase in leaves (Zbiec et al., 1999). Andres et al. (1990) studied the effects of alcohols (methanol, ethanol, propanol, butanol) on the association of the thylakoid membrane with fructose-1,6-bisphosphatase (FBPase), one of the principal enzymes controlling the activity of the photosynthetic carbon reduction cycle. They found that moderately concentrated (2-20%) alcohols stabilized the hydrophobic binding between FBPase and other membrane bound proteins, probably due to the hydrophobic character of the alcohols, and increased FBPase activity. Alcohols have been shown to delay senescence of oat (Avena fatua) via inhibition of the ethylene production (Satler et al., 1980). Hemming et al. (1995) measured metabolic heat rate, carbon dioxide production and oxygen uptake rates of bell pepper (Capsicum annuum L.) after exposing leaf tissues to methanol. They reported a strict increase in carbon conversion efficiency which lasted several weeks. Frequent methanol applications reduce the requirement for fungicide application to mildew (Sphacrotheca panosa) (Rajala et al., 1998). Methanol enhanced the growth of oilseed rape, soybeans, small beans, cabbage and sugar beet (Zbiec et al., 2003). It has been reported that foliar application of methanol caused increase in seed cotton yield and it had positive effect on physiological processes, water relation and plant structure (Makhdum et al., 2002). Also in another experiment on sunflower (Helianthus annuus L.) methanol increased stem length, leaf area index, stem dry weight, number of floret primordial and accelerated completion of floral development by 5 day (Hernandez et al., 2000). As f