Changes of some growth factors in tobacco (Nicotiana tabacum) under drought stress using potassium nano-chelate

The use of nano-chelates, in lieu of conventional fertilizers, result in the controlled and gradual release of the nutrients throughout the growth seasons. Drought stress is one of the stresses that lead to reduced tobacco farming yields. Potassium-containing fertilisers play an important role in improving the quality of tobacco and under draught conditions, higher levels of potassium reduce the damaging effects of the draught stress. In this study, we initially subjected tobacco plants to a drought stress induced by 20% polyethylene glycol, 48 hours after which the plants were treated with three concentrations of potassium nano-chelate over 9 days. .The amounts of proline, total proteins, photosynthetic pigments, malondialdehyde, phenol and potassium in the leaf were determined and the results were statistically analyzed by SPSS software. The results showed that increase in the duration of treatments and higher concentrations of potassium nano-chelates decrease the drought-induced deleterious effects in tobacco leaves, as revealed by lower amounts of proline, malondialdehyde and phenol, whose concentrations are generally elevated in drought-stressed plants. Further biochemical analyses revealed that increase in the synthesis of proteins, chlorophylls and carotenoids. In conclusion, the results of this study suggest that, in a shorter time nano-chelates of potassium reduce the destructive effects of the draught stress