Journal of Plant Process and Function

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In order to study the effects of cycocle and plant growth promoting rhizobacteria (PGPR) on yield, Chlorophyll fluorescence parameters and some physiological traits of wheat under water limitation condition, a factorial experiment based on randomized complete block design with three replications was conducted at the research farm of faculty of agricultural sciences, University of Mohaghegh Ardabili, during 2015-2016 cropping season. Factors were water limitation at three levels (full irrigation, irrigation to 50% of heading and booting stages, according with 45 and 59 Zadoks code respectively), seed inoculation with bio fertilizers at four levels (without inoculation as control, seed inoculation with Azotobacter chrocoocum strain 5, Pseudomonas putida strain 186 and inoculation with Azotobacter+ Pseudomonas) and foliar application of cycocle at four levels (0, 400, 800 and 1200 mg.lit-1). Means comparison showed that under water limitation condition, maximum photochemical efficiency of photosystem II ( ), chlorophyll content, relative water content, grain yield increased due to seed inoculation with PGPR and foliar application of cycocle compared to control treatment. In all of treatment compounds, leaf area index increased rapidly to 65 days after emergence, but from 65 days after emergence till harvest time, it decreased slowly. The highest grain yield was belonged to inoculation seed with Azotobacter and Pseudomonas, the high cycocle rates under full irrigation condition. Irrigation withholding in boot stage was caused the highest decline in chlorophyll fluorescence parameters and physiological traits of wheat. Foliar application of 1200 mg.lit-1 cycocle and seed inoculation with Azotobacter and Pseudomonas increased grain yield 63.41, 52.90 and 62.46% respectively at full irrigation, irrigation to 50% of heading and booting stages