Effect of spraying thiamin and salicylic acid on growth and flowering of Zinnia elegans L

This study was conducted during spring and summer seasons of 2011 to study the effect of foliar spraying of thiamin at 0, 60 and 120 mg L-1 and/or salicylic acid at 0, 25 and 50 mg L-1 on growth and flowering of Zinnia plant in a factorial experiment designed with R.C.B.D. Means were compared according to R.L.S.D test at probability 0.05. Results showed a significant increase in plant height, number of leaves plant-1 , leaf area, (dry matter, total chlorophyll, protein, phosphorus and potassium content in leaves), number of roots plant-1 , root dry weight, number of flowers plant-1 , flower diameter, dry weight of flowers and vase life when spraying with thiamin at 120 mg L-1 or salicylic acid at 50 mg L-1 .The interaction between the two factors increased significantly the number of leaves plant-1 to 32.00 when spraying with 120 mg L-1 thiamin + 25 mg L-1 salicylic acid, whereas spraying with thiamin at 120 mg L-1 + salicylic acid at 50 mg L -1 increased significantly number of roots plant-1 , root dry weight, number of flowers plant-1 and flower diameter to (10.20 root plant-1 , 0.499 g, 16.00 flower plant-1 and 8.68 cm, respectively) as compared to distilled water treatment which gave (6.30 root plant-1 , 0.31 g, 11.30 flower plant-1 and 5.85 cm, respectively).