STIMULATIVE EFFECTS OF SEAWEED AND ACTIVE YEAST EXTRACTS AS FOLIAR TREATMENTS ON GROWTH AND PRODUCTIVITY OF GLADIOLUS GRANDIFLORUS ANDREWS ‘WHITE PROSPERITY’

In view of the availability, safety and beneficial effects of both yeast at 0, 3, 5 and 7 g/l and seaweed extract at 0, 50, 100 and 150 ppm, the current experiment aimed at studying the ability of different concentrations of both substances to enhance growth, flowering and corm production of gladiolus ‘White Prosperity’ plants. The results showed that both dry yeast extract and seaweed extract are promising growth stimulants for gladiolus plants. It is obvious that the heaviest and longest spikes and rachis were obtained in gladiolus plants subjected to the foliar application of 5 g/l yeast alone. When yeast at 5 g/l was combined with seaweed extract at 100 or 150 ppm, the longest flowering duration was recorded. Increasing yeast concentration to 7 g/l in combination with seaweed extract at 100 ppm showed the best characteristics of the new corm including corm FW, DW and diameter. However, the combination of yeast at 5 g/l and seaweed extract at 50 ppm produced the highest number of cormels/corm. Accordingly, it could be recommended to spray gladiolus plants cultivated for the production of cut flowers with yeast extract at 5 g/l combined with seaweed extract at 100 ppm. Meanwhile, for the purpose of cormels production, it is recommended to use 7 g/l yeast with 100 ppm seaweed extract.