Two field experiments were carried out to investigate effects of spraying organic acids and amino acids and combinations between organic acid and potassium citrate or amino acid and potassium citrate under drought stress. The objectives of these studies were aimed to investigate the effect of organic and amino acids application and potassium citrate on plant growth characters, yield and yield components, leaf chemical constituents, enzyme activity as well as seed quality and fiber properties of Giza 86 cotton cultivar. The experiments were conducted at Sakha Agricultural Research station, during 2009 and 2010 seasons.Plant irrigation was carried out regularly at plant needs using tap water up to the start of flowering stage then, some of plants subjected to drought conditions by preventing water supply till the appearance of sign of wilting and spraying with organic acids or amino acids and potassium citrate, leaving the control plants without treatments.Drought conditions significantly decreased plant height, number of fruiting branches, chloroplast pigments i.e., chlorophyll a, b, a + b, carotein and catalase activity in cotton leaves, while the contrary was obtained in proline content in leaf and peroxidase activity in comparison with the control. Also, reduction in yield and yield components was observed as results of water stress.The results clearly showed that spraying cotton plants with organic acid, amino acid and combinations between them and potassium citrate under drought conditions tended to increase growth parameters i.e., plant height, number of fruiting branches, number of open bolls per plant, seed index, boll weight, lint percentage, seed cotton yield per feddan and some chemical content in cotton leaves i.e., chlorophyll a, b, total chlorophyll and carotein, proline and antioxidant enzyme activities.On the other hand, no significant effects with application of organic and amino acids on fiber properties.
