EFFECT OF COMPOST, SALICYLIC AND ASCORBIC ACIDS TREATMENTS ON VEGETATIVE GROWTH AND FLOWERING OF GLADIOLUS GRANDIFLORUS CV. WHITE PROSPERITY

A field experiment was carried out during the two successive seasons of 2012/2013 and 2013/2014. The aim of this study was to investigate the effect of compost at four levels (0, 7.5, 10.0 and 12.5 ton/fed) in combination with salicylic and/or ascorbic acids, each at 100 and 200 ppm, in addition to the control on growth and flowering of Gladiolus grandiflorus cv. White Prosperity. Results showed that leaf length, leaf area, number of leaves/plant, leaves dry weight/plant, length of spike, rachis length, spike diameter, number of florets/spike, lower floret diameter and single floret fresh weight were gradually increased by increasing the levels of compost with significant differences were detected between successive treatments. Also, all salicylic and/or ascorbic acid treatments significantly increased all vegetative growth and flowering parameters in comparison with the control. Salicylic plus ascorbic one at 100 ppm  for each, followed by ascorbic acid alone at 200 ppm were more effective in this concern. It was found also that the use of compost (12.5 ton/fed) in combination with salicylic acid + ascorbic acid, each at 100 ppm or with ascorbic acid at 200 ppm noticeably improved the different vegetative growth characters and flowering parameters of gladiolus plants.