الفهرس 
EFFECT OF LEVELS AND APPLICATION METHODS OF IRON AND ZINC ON GROWTH AND FLOWERING OF HYBRID ROSEOnly 14 pages are availabe for public view
 |  | from | 116 |  |  |
| | | from | 116 | | |
Abstract
The present study was carried out during two successive seasons of 2012 / 2013 and
2013 / 2014 at a commercial nursery for flower and ornamental plants in suburb of Alexandria city to investigate the effect of different concentrations and application methods of iron and
zinc as chelated fertilizers on vegetative growth, flowering characteristics and some chemical analysis of Rosa hybrida cv. ”Dallas” for its importance in flower trade.
The chelated iron (Fe-EDDHA) was used with four concentrations i.e. zero (control),
30, 60 and 120 ppm, while the chelated zinc (Zn-EDTA) was used with three concentrations i.e. zero (control), 75 and 150 ppm. The chelated fertilizers were used on the plants singly and with all possible combinations between them as a foliar spraying and / or to the pot-medium
dissolving in irrigation water (soil drench or with irrigation water or with irrigation water).
The fertilizer treatments were started for the first time after three weeks from the final transplanting date, then they were repeated weekly for three other times. The plants were left for 6 months from the last treatment for the evaluation.
The experiment lay-out was designed to provide a split-split plot design, where the application method was the main plot, iron concentration was the sub plot, while zinc concentration was the sub-sub plot. The experiment contained three replicates and each replicate had 24 treatments and 4 plants were used for each treatment in the replicate as a plot
unit.
The main results of the two experimental seasons can be summarized in the following
points:
1- Using the two elements (iron and / or zinc) singly or in combination as a foliar
spraying on Rosa hybrida cv. ”Dallas” led to positive significant effect on all the
studied parameters, compared with adding them as a soil drench or with irrigation
water.
2- Spraying iron alone at 30 ppm on the foliage of the used cultivar gave the highest
earliness of flowering and the highest increases of flower diameter, flower
duration on plant, flower stalk length, flower fresh weight and leaves fresh weight
of flower stalk, compared with the other treatments.
3- Spraying iron alone at 60 ppm on the plant foliage gave the highest significant
increases of plant height, weight of the blind shoots (dry) per plant, leaf
chlorophyll index and total carbohydrates (%), compared with the other
treatments.
4- While spraying zinc alone at 75 ppm on the foliage of the used cultivar ”Dallas”
gave the highest significant increase of the dry weight of stalk leaves only,
compared with the other treatments.
5- Adding iron at 30 ppm combined with zinc at 75 ppm gave the highest significant
increases of number of the blind shoots per plant, number of the cut flowers per
plant, stalk diameter, flower dry weight and leaf total zinc content, compared with
the other treatments.
6- While adding iron at 60 ppm combined with zinc at 75 ppm gave the highest
significant increases of leaf area of the blind shoots, leaves dry weight of the blind shoots and leaf total iron content, compared with the other treatments.
7- Adding the two used elements at their highest concentrations (120 ppm iron or 150 ppm zinc) alone or in combinations led to decrease most of the studied parameters
of Rosa hybrida cv. ”Dallas”, compared with their lower concentrations.
104 from the previous results it can be recommended to spray Rosa hybrida cv. ”Dallas”
four times during the vegetative growth period with chelated iron (Fe-EDDHA) alone
at 30 ppm or combined with chelated zinc (Zn-EDTA) at 75 ppm to activate the
vegetative growth of the plants and produced early flowering with a high quantity and quality.