Evaluting the Nutrient Uptake and Tomato Growth by Pseudomonads Isolates and Mineral Potassium levels

Potassium is an essential macronutrient for plants that plays many important roles in the plant growth and development as well as in the quality of crops. In this study the effect of five bacterial strains belong to Pseudomonas genus including S6-6, S10-3, S14-3, S19-1 and S21-1 were assessed on the growth and K uptake by tomato plant in the non-sterile soil with low available potassium (less than 200 mg.kg-1). The experiment was conducted factorial based on CRD with three replications. The first factor consisted of bacterial inoculum (5 strains and control) and the second factor consisted of three levels of potassium fertilizer, 0 kg.ha-1, 50% (150 kg.ha-1) and 100% of the recommended amount (300 kg.ha-1), respectively. The results showed that maximum amount of wet and dry weight was gained at 50% of K fertilizer, while with application of K (300 kg.ha-1) fertilizer it was decreased. The main effects of bacteria were significant on yield, chlorophyll index, content of K, the concentration of P, Fe, Zn, Mg and Ca. The highest amount of wet and dry weight of shoot was obtained with S6-6 (54.76 g.pot-1 and 7.76 g.pot-1). The highest amount of root dry weight was measured with S14-3 (1.2 g.pot-1), S19-1 (1.17 g.pot-1) and S21-1 (1.16 g.pot-1). From the nutritional view of point two isolates, S21-1 and S14-3 were better than the other isolates. The highest concentration of shoot P, Fe and concentration of root Mg and P belonged to the S21-1. The highest concentration of shoot Mg and P was by the S14-3. All the bacterial strains at 50% level of K fertilizer (150 kg.ha-1) had better yield and maximum wet and dry weight of shoot was measured with strain S6-6 (62.066 g.pot-1 and 9.203 g.pot-1) at 150 kg.ha-1 level of K fertilizer.