The effect of different levels of Fe-EDTA on growth and physiological traits of cucumber in different pH of nutrient solution

Iron (Fe) absorption control by pH of substrate or nutrient solution that during growth and nutrient absorbtion of nutrient solution its pH will change and will affect Fe absorbtion. In order to study of different pH levels and different iron concentration on vegetative and photosynthesis traits of cucumber cv. N3 this experiment was designed. Experiment was conducted as a factorial experiment based on CRD with 3 level of pH included 5(acidic), 7(natural) and 8 (alkaline) and Fe concentration with 25, 50 and 100 % of Fe concentration of Johnson nutrient solution with 3 replications in greenhouse of Isfahan University of technology. The result of this experiment showed that transpiration and stomatal conductance decreased with acidification compared to natural and alkaline conditions. Photosynthesis and phenol content of shoot and root increased in acidity condition compared to other conditions. The highest stomata conductance, transpiration and photosynthesis were observed with 25 and 100% Fe, respectively. The result of interaction between Fe and pH showed that alkaline condition caused a reduction of shoot phenol and photosynthesis and by using high Fe concentration it was improved. In general, with acidification of nutrient solution or using high iron concentration the deleterious effect of gradual alkaline nutrient solution was improved in cucumber.