Effect of gibberellic acid and potassium nitrate spray on vegetative growth and reproductive characteristics of tomato

A study was carried out to investigate the effect of 2 levels of gibberellic acid (10-4 and 10-8 ) and 2 levels of potassium nitrate (6 and 8 mM) spray on the growth, leaf-NPK content, yield and quality parameters of tomato. The application of gibberellic acid and potassium alone or in combination increased plant height, number of branches, number flowers per cluster, number fruits per cluster and faster fruit growth in addition to increasing fruit number, fruit firmness, weight and yield. The chlorophyll content, leafNPK content, blossom end rot and nitrate reductase activity were not affected by application of GA3 alone or in combination, but K application alone significant decreased blossom end rot while increasing leaf-NPK content, chlorophyll content and nitrate reductase activity. With regard to fruit quality, the application of GA3 at 10-8 mM, 8 mM potassium nitrate and 10-8 mM GA3+ 8 mM potassium nitrate increased fruit lycopene content, total soluble solids, vitamin C and titratable acidity compared with the control treatment. From this study, it can be concluded that spraying with gibberellic acid and potassium alone or in combination increased vegetative growth and reproductive characteristics of tomato