الفهرس 
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Abstract
The present investigation was executed as a field experiment during two successive seasons of 2003 / 2004 and 2004 / 2005 to explore the effect of foliar fertilization in form of Kristalon (N 19 : P 19 : K 19 : Mg 1.5) and two antioxidants namely, salicylic and ascorbic acids and their interaction on the vegetative growth traits, flowering aspects, yield of alkaloids and chemical composition of borage, Borago officinalis plants Kristalon was foliar sprayed at 2, 4 and 6 g / l and both two antioxidants were also foliar sprayed each at 100, 200 and 300 ppm.
The most important results of this study could be summarized as follows :
I- Effect of foliar fertilization :
Vegetative growth traits :
All foliar fertilizer (Kristalon) treatments (2, 4 and 6 g / l) gave significant increment of vegetative growth traits including plant height, stem diameter, branch number / plant, as well as, herb fresh and dry weights of Borago officinalis plants in comparison with check treatment. The most effective foliar fertilization treatment which resulted in the tallest plants, thickest stems, heiher number of branches / plant, as well as, the heaviest fresh and dry weights of borage plants was Kristalon at 2 g / l.
Flowering aspects :
Flowering aspects of borage plants i.e. total number of flowers / plant, and flower fresh and dry weights / plant were significantly augmented due to application of foliar fertilizer treatments in comparison with untreated plants. Kristalon at 2 g / l gave the highest values of the aforementioned flowering aspects.
Total alkaloids content :
Total alkaloids content calculated as mg / g D.W of the herb of borage plants was promoted due to foliar fertilization treatments compared with control and Kristalon at 4 g / l (medium concentration) resulted in the highest content.
Total alkaloids content (yield) / plant was significantly stimulated by application of foliar fertilizer at 2, 4 and 6 g / l compared with untreated plants. The highest yield / plant of total alkaloids in the herb was obtained as a result of Kristalon at 2 g / l.
Chemical composition :
Supplying borage plants with foliar fertilizer i.e. Kristalon at 2, 4 and 6 g / l enhanced significantly the content of three photosynthetic pigments (chlorophyll a, b and carotenoids) in the fresh leaves compared with zero g / l. The highest content of these three pigments was obtained from plants received Kristalon at 2 g / l.
Treating borage plants with Kristalon at different concentrations (2, 4 and 6 g / l) led to increase of the percentages of nitrogen, phosphorus and potassium in the dried herb compared with unfertilized plants. The highest percent of each element was found in the herb of plants treated with Kristalon at 2 g / l.
II- Effect of antioxidants :
Vegetative growth traits :
Spraying Borago officinalis plants with salicylic acid or ascorbic acid each applied at three concentrations i.e. 100, 200 and 300 ppm resulted in taller plants, thicker stems, more branches / plant, as well as, heavier fresh and dry weight of herb / plant than those of untreated plants (control). The most effective treatments which gave the highest values regarding the vegetative growth traits were, in most cases, ascorbic acid at 300 ppm and salicylic acid at 300 ppm.
Flowering aspects :
Using of salicylic acid or ascorbic acid each at 100, 200 and 300 ppm as foliar spray on borage plants significantly improved total number of flowers / plant and fresh and dry weights of flowers / plant in comparison with untreated plants. In most cases, the highest concentration (300 ppm) of each antioxidant was the most beneficial treatment which resulted in the maximum values.
Total alkaloids content :
Salicylic acid and ascorbic acid each sprayed on borage plants at 100, 200 and 300 ppm increased the content of total alkaloids in the herb calculated either as mg / g D.W. or as mg / plant (yield / plant). The high concentration (300 ppm) of both two examined antioxidants was the most positive concentration.
Chemical composition :
The content of chlorophyll a, b and carotenoids in the fresh leaves of borage plants was higher due to antioxidant treatments than those of control treatment. The highest content of the photosynthetic pigments was resulted from application of ascorbic acid or salicylic acid each at 300 ppm.
The percentage of N, P and K in the dry herb of borage plants was augmented by spraying the plants with salicylic acid or ascorbic acid at the three tested concentrations, 100, 200 and 300 ppm compared with untreated plants. The high concentration of each antioxidant (300 ppm) gave higher N, P and K % than those of other treatments.
III- Effect of the interaction :
Vegetative growth traits :
Generally, the interaction between foliar fertilization and antioxidants had significant influence on vegetative growth traits of Borago officinalis plants including plant height, stem diameter, branch number / plant, as well as, fresh and dry weight. The most effective interaction treatments which gave the maximum values were application of Kristalon at 2 g / l + ascorbic acid at 300 ppm and Kristalon at 2 g / l + salicylic acid at 300 ppm.
Flowering aspects :
The interaction between foliar fertilization and antioxidants had significant and stimulative effect on total number of flowers / plant and fresh and dry weights of flowers / plant. The highest number of flowers / plant and the heaviest fresh and dry weight of flowers / plants were obtained due to application of Kristalon at 2 g / l in combination with ascorbic acid or with salicylic acid each at the high concentration (300 ppm).
Total alkaloids content :
The content of total alkaloids in the herb of Borago officinalis plants either as mg / g D.W. or as mg / plant (yield / plant) was affected significantly by interaction treatments. The highest content (yield / plant) was obtained from plants sprayed with Kristalon at 2 g / l + ascorbic acid at 300 ppm.
Chemical composition :
Interaction treatments enhanced the content of chlorophyll a and carotenoids in the fresh leaves of Borago officinalis plants.
The percentage of nitrogen and potassium in the dry herb of borage plants was influenced significantly by interaction treatments.
Recommendation :
From the obtained results concerning the effect of foliar fertilization, antioxidants and their interaction, it could be recommended to spray borage, Borago officinalis plants with a foliar fertilizer (19 % N, 19 % P, 19 % K, 1.5 % Mg) at 2 g / l and treating the plants with ascorbic acid or salicylic acid each at 300 ppm to improve the vegetative growth, flowering aspects, and total alkaloids yield / plant, as well as, chemical composition of borage plants under the conditions of Upper Egypt Governorates.