Effect of irrigation interval, humic acid and plant growth promoting rhizobacteria on physiological characteristics of Kavir cultivar wheat in Shahr Rey

In order to investigate the effect of irrigation interval, humic acid and plant growth promoting rhizobacteria on relative humidity content, the resistance amount of cell membrane, chlorophyll content and amount of wheat leaf proline this experiment was done during 2010-2011 cropping year, as split factorial in the basis of completely randomized blocks design in four replications in Fashafuyeh Shahr-e-Rey. Main factor (irrigation) in 3 levels (irrigation after 80, 120 and 160 millimeter evaporation from evaporation pan surface class A) and humic acid and a mixture of Plant Growth Promoting Rhizobacteria (PGPR) each in 2 levels application and non-application as factorial considered as sub-factor. The results of the analysis of variance showed that the effect of irrigation interval on all traits was significant, excepting content of chlorophyll a at possibility level of one percent. While effect of humic acid demonstrated significant difference in all traits except for content of relative humidity content at the possibility level of one percent and effect of growth stimulus bacteria showed such significant difference only for content of chlorophyll a at the level of five percent and the leakage of cytoplasmic materials and proline amount at the possibility level of one percent. In humic acid applying treatment, the highest amount of chlorophyll a at two levels of irrigation after 80 and 120 millimeter evaporation was at the rate of 0.0212 and 0.0206 mg/cm and maximum leakage of cytoplasmic membrane due to the absence of applying humic acid, in severe moisture tension (after 160 mm evaporation) at the rate of 663.06 ms/cm. The rate of leaf proline in all irrigation levels increased after using humic acid and with increasing the tension intensity equals 171.9250, 152.4875 and 107.6875 microgram on leaf fresh weight unit, respectively.