Physiological studies on the effect of kinetin and salicylic acid on growth and yield of wheat plant

Abstract

Field experiments were carried out during 2002-2003 and 2003-2004 seasons to investigate the effect of kinetin (Kin) at 25 and 50 ppm and salicylic acid (SA) at 10 and 20 ppm on growth and yield of wheat, Triticum vulgare L. cv. Sakha 69. Kin and SA were applied during vegetative growth stage (21 days from sowing). Three samples were taken at 31, 105 and 155 days from sowing. Application of Kin at 25 and 50 ppm showed an increase in plant dry weight, soluble protein, chlorophyll concentrations in the fifth leaf (L5) and flag leaf, 1000 grains weight, grains yield (ardab/fed), total soluble carbohydrates and soluble proteins in grains comparing with control. Application of SA enhanced flag leaf area, soluble protein and chlorophyll concentrations in the leaves of the 1st sample. No significant effects were obtained by SA on grains yield. Application of Kin and SA showed an increase in zeatin and IAA concentrations in flag leaf. SA at 10 and 20 ppm showed an increase in zeatin while the low concentration reduced IAA concentration. In respect to growth regulator combinations, double applications of Kin with SA showed promoting effects on soluble protein and chlorophyll concentrations, 1000 grains weight, grains weight/plant and grains yield ardab /fed. The combination of Kin at 50 ppm with SA 20 ppm gave the best results comparing with control and other treatments. Finally, changes in growth parameters, chlorophyll, total soluble carbohydrates, soluble proteins and phytohormones in flag leaf in relation to yield capacity were discussed