الفهرس 
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Abstract
The present study was determined to investigate the effects of different types of fertilizer i.e. bio, mineral and organic and their interactions on vegetative growth, head yields, physical quality, mineral content, nutritional value, anti-oxidant materials and free radical scavenging activity of broccoli plants (Brassica oleracea var. italica Plenck).
The field experiment was conducted at the farm of National Research centre, at Nobaria, Alexandria Governorate, Egypt during two successive winter seasons 2012/2013 and 2013/2014. A split plot system with three replicates was followed. Five treatments of bio-fertilizers were allotted in the main plots using mixture of nitrogen fixing and phosphorus solubilizing microorganisms (Aztobacter chroococcum, Bacillus megaterium, Arbiscular mycorrhizea, Bacillus polymyxa). Four equations of mineral and organic fertilizers i.e. 100% mineral, 75% mineral+25% organic, 50% mineral+ 50% organic, 25% mineral+ 75% organic of the recommended fertilizers units were assigned in the sub-plots.
The obtained results can be summarized as follows:
І) Vegetative growth:
1- Bio-fertilization affected significantly the vegetative growth of broccoli plants expressed as plant height, leaves number, leaf area, stem length and diameter, fresh and dry weights of plants. These parameters recorded its highest values with application of Bio 2 (Azotobacter+ mycorrhizae) treatment compared with the other treatments in the two seasons.
2- Results indicated that mineral and organic fertilizers treatments varied significantly in their vegetative growth expressed as plant height, leaves number, stem length and diameter as well as fresh and dry weights. Treatment of 75% mineral+ 25% organic of the recommended fertilizer units gave the highest values of the abovementioned vegetative growth parameters compared with the other mineral and organic fertilizers.
3- The combined effect of bio, mineral and organic fertilization led to significant increase in vegetative growth characteristics of broccoli plants. Bio 2 in combination with 75% mineral+ 25% organic of the recommended fertilizer units recorded the highest values of plant length, leaves number, leaf area, stem diameter, fresh and dry weights of plants. While, the treatment of 25% mineral+ 75% organic of the recommended fertilizer units without adding biofertilizer recorded the lowest values of vegetative growth characteristics.
П) Mineral content in leaves:
1- Bio-fertilization influenced significantly N, P, K, Ca and Mg contents of broccoli leaves. Higher values of N, P, K, Ca and Mg percentages of leaves tissues were recorded by Bio 2 treatment. Lower N, P, K, Ca and Mg% were recorded by the non-inoculated plants.
2- Treatment of 75% mineral+ 25% organic of the recommended fertilizer units led to the highest values of nitrogen, phosphorus, potassium, calcium and magnesium percentages in leaves tissues followed by 100% mineral of the recommended fertilizer units without significant differences between them. While the lowest values of mineral content in leaves were detected by the treatment of 25% mineral+ 75% organic of the recommended fertilizer units in both seasons.
3- The highest values of N, P, K, Ca and Mg percentages of broccoli leaves were recorded by Bio 2 in combination with 75% mineral+ 25% organic of the recommended fertilizer units. On the other contrary, the lowest values were recorded by plants receiving 25% mineral+ 75% organic of the recommended fertilizer units (without biofertilizer addition).
Ш) Head yield and its components:
1- The highest main, secondary and total heads yield of broccoli plants per Feddan were produced by Bio 2 treatment in both seasons. Whereas, the non-inoculated plants produced the lowest main, secondary and total heads yield.
2- The treatment of 75% mineral+ 25% organic of the recommended fertilizer units produced the highest main, secondary and total heads yield per Feddan followed by application of 100% mineral of the recommended fertilizer units in the two seasons.
3- The combination of bio, mineral and organic fertilization led to significant increase in head yield of main, secondary and total heads yield of broccoli plant. Bio 2 with 75% mineral+ 25% organic of the recommended fertilizer units produced the highest significant main, secondary and total heads yields. While, the lowest values were recorded by plants receiving 25% mineral+ 75% organic of the recommended fertilizer units without adding biofertilizer in the two seasons.
IV) Quality of heads:
A. Physical quality:
1- Physical quality of broccoli heads was affected by bio-fertilization. The highest values of fresh weight, height and diameter of heads as well as number of stalks per head were recorded by Bio 2 treatment as compared with the other treatments.
2- Main heads of broccoli plants receiving 75% mineral+ 25% organic of the recommended fertilizer units recorded higher values of fresh weight, height, diameter and number of stalks per head. On the other hand, lower values of physical quality parameters were obtained by 25% mineral+ 75% organic of the recommended fertilizer units in the two seasons.
3- Interaction of bio, mineral and organic fertilization increased significantly physical quality of main heads. The highest values of fresh weight, height, diameter and number of stalks per head were recorded with the combined application of Bio 2 with 75% mineral+ 25% organic of the recommended fertilizer units. However, the lowest interaction was recorded by 25% mineral+ 75% organic of the recommended fertilizer units without any bio-fertilizer addition in both seasons.
B) Chemical quality:
1. Nutritional values of main head:
1-Bio-fertilization significantly affected nutritional values of broccoli heads. The main heads of the Bio 2 treatment recorded the highest values of dry weight, crude protein, phosphorus, potassium, calcium and magnesium percentages. These values followed in a descending order by Bio 4 and Bio 1 in both seasons. However, main heads of the non-inoculated plants recorded the lowest values in the two seasons.
2- The treatment of 75% mineral+ 25% organic of the recommended fertilizer units recorded the highest values of dry weight, crude protein, phosphorus, potassium, calcium and magnesium. The treatment of 25% mineral+ 75% organic of the recommended fertilizer units gave the lowest values in the two seasons.
3- The combined effect of bio, mineral and organic fertilization enhanced significantly nutritional values of broccoli heads. Bio 2 in combination with 75% mineral+ 25% organic of the recommended fertilizer units recorded the highest percentage of dry weight, crude protein, P, K, Ca and Mg.
2. Anti-oxidant materials content:
1- Bio fertilization led to negative effects on antioxidant materials such as vitamin C, total phenols and total flavonoids. The non-inoculated plants (without bio-fertilizer addition) recorded higher values of vitamin C, total phenols and total flavonoids. However, the previous treatment recorded lower head contents of total chlorophyll and carotenoids.
2- Results indicated that mineral and organic fertilizers treatments varied significantly in their anti-oxidant materials content expressed as vitamin C, total phenols, total flavonoids, total chlorophyll and total carotenoids. Treatment of 25% mineral+ 75% organic of the recommended fertilizer units was superior in the above mentioned parameters except with total chlorophyll and total carotenoids compared with the other treatments.
3- The non-inoculated plants with 25% mineral+ 75% organic of the recommended fertilizer units recorded the highest values of vitamin C, total phenols, total flavonoids except with total chlorophyll and total carotenoids content of broccoli heads. While Bio 2 in combination with 75% mineral+ 25% organic of the recommended fertilizer units recorded the lowest values of vitamin C, total phenol and total flavonoids. In addition, the pervious treatment recorded the highest values of total chlorophyll and total carotenoids content of broccoli heads in the two seasons.
3. Free radical scavenging activity:
1- The non-inoculated plants (without bio-fertilizer addition) recorded higher activity of scavenging DPPH free radical compared to the other treatments. However, Bio 2 treatment recorded lower activity of scavenging DPPH free radical.
2- Results indicated that mineral and organic fertilizers treatments varied significantly in their activity of scavenging DPPH free radical. Treatment of 25% mineral+ 75% organic of the recommended fertilizer units was superior in the above mentioned parameter compared with the other treatments.
3- The non-inoculated plants with 25% mineral+ 75% organic of the recommended fertilizer units recorded the highest activity of scavenging DPPH free radical compared to the other treatments. While Bio 2 in combination with 100% mineral of the recommended fertilizer units recorded the lowest activity of scavenging DPPH free radical.