Two field experiments were conducted to investigate the effect of plant compost (0, 2.5, 5.0 and 7.5 ton/fed) and six natural stimulants (green tea extract at 5 g/l, moringa leaves extract at 300 mg/l, garlic extract at 300 mg/l, licorice roots extract at 5 g/l, active dry yeast at 5 g/l and seaweeds extract at 3 cm³/l) on corms production and chemical constituents of Gladiolus grandiflorus cv. Peter Pears.
The obtained results indicated that corm diameter, number of cormels/plant, dry weight of cormels, as well as, chemical constituents including chlorophyll a, b, carotenoids and percentages of N, P and K in the corms were gradually increased by increasing the level of compost. Significant differences were detected among the four used treatments. So, the high level of compost resulted the highest values.
All six treatments of natural stimulants significantly increased corm and cormels production and their content of chemical constituents in comparison of the control plants. The highest values were obtained due to the treatments of seaweeds extract at 3 cm³/l. or active dry yeast at 5 g/l.
The interaction between compost and natural stimulants was significant for all previous characters, except chlorophyll a in the first season.