الفهرس 
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Abstract
The present study was conducted in split plot design at Nursery and Laboratory of Floriculture, Faculty of Agriculture, Minia University during two successive seasons of 2014/2015 and 2015/2016 in order to explore the response of Gladiolus grandiflorus cv. Peter Pears in terms of vegetative growth, flowering aspects, corm production and some chemical constituents to four levels of compost (0, 2.5, 5.0 and 7.5 ton/fed.) in the main plots. While, seven treatments of 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 5g/l., active dry yeast at 5 g/l. and seaweeds extract at 3 cm3/l. and the control). Occupied the sub-plots, in addition to the interaction between the two factors.
The obtained results of the two growing seasons could be summarized as follows:
1- Effect of compost treatments:
1-1- Vegetative growth parameters:
• All of the vegetative growth traits (leaf length, leaf area, number of leaves/plant, fresh and dry weights of leaves/plant) were considerably increased as a result of fertilizing gladiolus with the three levels of compost (2.5, 5.0 and 7.5 ton/fed.) in comparison with control treatment. The high level of compost (7.5 ton/fed.) gave the highest values in both seasons.
1-2- Flowering parameters:
• Flowering parameters including spike length, rachis length, spike diameter, spike fresh and dry weights, number of florets/spike, lower floret diameter and fresh and dry weights of single floret were remarkably increased due to different compost fertilization treatments comparing with control treatment. The highest values for all flower parameters were resulted from compost at high level (7.5 ton/fed.).
1-3- Corms and cormels production:
• Various corm and cormels parameters including corm diameter, fresh and dry weights of corm, cormels number, as well as, fresh and dry weights of cormelets were significantly increased due to fertilizing gladiolus with all used levels of compost comparing with control treatment. The increase in these characters was gradual a parallel to the gradual rise in compost level from zero to 7.5 ton/fed.
1-4- Chemical constituents:
• Chemical constituents of gladiolus plants including the content of three photosynthetic pigments (chlorophyll a, b and carotenoids), auxin – like substances in the fresh leaves, total carbohydrates content in corms and N, P and K percentages in the leaves and corms were greatly promoted due to the three levels of compost. The maximum values were recorded at the highest level of compost (7.5 ton/fed.).
2- Effect of natural stimulants treatments:
2-1- Vegetative growth parameters:
• All vegetative growth parameters (leaf length and area, number of leaves/plant and fresh and dry weights of leaves/plant) were significantly increased due to use all 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 5g/l., active dry yeast at 5 g/l. and seaweeds extract at 3 cm3/l.) treatments comparing with control treatment. Among the six tested treatments, the treatment of seaweeds extract at 3 cm3/l. resulted the highest values.
2-2- Flowering parameters:
• Using all treatments of natural stimulants led to significantly increase in the spike length, spike diameter, rachis length, fresh and dry weights of spike, as well as, number of florets, lower floret diameter and lower floret fresh and dry weights in comparison with control treatment. Active dry yeast at 5 g/l. followed by seaweeds extract at 3 cm3/l. gave the highest values during both seasons.
2-3-Corms and cormels production:
• All corms and cormels parameters, namely corm diameter, fresh and dry weights of corm, cormels number and fresh and dry weights of cormels/plant were significantly increased by used all treatments of natural stimulants in comparison with control treatment. The highest values were obtained due to the treatments of seaweeds extract at 3cm3/l. followed by active dry yeast at 5 g/l. then licorice roots extract at 5 g/l. in both seasons.
2-4- Chemical constituents:
• Chlorophyll a, b and carotenoids contents in the fresh leaves of gladiolus plants were significantly increased in comparison with control. The highest values were obtained with plants sprayed seaweeds extract at 3 cm3/l. followed by active dry yeast at 5 g/l. without significant differences between such two superior treatments, except chlorophyll a during the first season.
• Auxin – like substances contents in fresh leaves of gladiolus significantly increased due to all natural stimulants comparing with control. The most effective treatment which gave the highest value was seaweeds extract at 3 cm3/l.
• All six used treatments significantly promoting the percentages of N, P and K in both dry leaves and corms of plants in comparison of control. The best results were obtained due to the use of seaweeds extract at 3 cm3/l. followed by active dry yeast at 5 g/l. without significant differences between them.
• Data showed that all of six natural stimulants treatments positively and significantly enhanced total carbohydrates contents in corms. The best treatment were given by the application of seaweeds extract at 3 cm3/l. followed by active dry yeast at 5 g/l.
3- Effect of the interaction treatments:
3-1- Vegetative growth parameters:
• The interaction between compost and natural stimulants treatments had significant influence on all vegetative growth parameters (leaf length, leaf area, number of leaves/plant and fresh and dry weights of leaves/plant). The highest values were resulted from fertilization gladiolus with compost at 7.5 ton/fed. and spraying with seaweeds extract at 3 cm3/l. followed by active dry yeast at 5 g/l.
3-2- Flowering parameters:
• The interaction between compost and natural stimulants treatments was significant for all studied flowering parameters in both seasons. The highest values were obtained with compost at 7.5 ton/fed. in combination with active dry yeast at 5 g/l. or seaweeds extract at 3 cm3/l. or licorice roots extract at 5 g/l. in some cases.
3-3- Corms and cormels production:
• The interaction between compost and natural stimulants treatments was significant for all studied parameters of corm and cormels production in both seasons. The highest values were obtained with compost (7.5 ton/fed.) in combination with seaweeds extract (3 cm3/l.) followed by active dry yeast (5 g/l.) without significant differences in some cases.
3-4- Chemical constituents:
• The interaction treatments were significant for the three photosynthetic pigments contents (chl. a, b and carotenoids, except, chl. a in the first season), auxin like substances in fresh leaves, total carbohydrates in corms, as well as, the percentages of nitrogen, phosphorus and potassium in dry leaves and corms.
• The most effective interaction treatment which resulted in the highest content of photosynthetic pigments, total carbohydrates in the corms and NPK percentages in the dry leaves of gladiolus was application of high level of compost (7.5 ton/fed.) plus seaweeds extract at 3 cm3/l.
• The highest auxin – like substances content was obtained due to adding compost (7.5 ton/fed.) in combination with seaweeds at 3 cm3/l. followed by compost (7.5 ton/fed.) in combination with active dry yeast extract at 5 g/l. then compost (7.5 ton/fed.) in combination with licorice roots extract at 5 g/l. without significant differences among the three treatments in the two growing seasons.
• The highest values for N, P and K% in corms were obtained due to fertilizing plants with high level of compost (7.5 ton/fed.) plus treating plants with seaweeds extract followed by active dry yeast without significant differences between them except in K% in the two growing seasons.
RECOMMENDATIONS
In order to obtain better vegetative growth along with high quality and quantity of flowering production and good corm and cormels formation of Gladiolus grandiflorus cv. Peter Pears, it preferable to fertilize such plants with compost at 7.5 ton/fed. and spraying plants with seaweeds extract at 3 cm3/l. or active dry yeast at 5 g/l.