Zaki, M.F., A.A.M. Abdelhafez and Camilia Y. El-Dewiny. Department of Vegetable Res., National Research Centre, Dokki, 2

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1 Australian Journal of Basic and Applied Sciences, 4(2): , 2010 ISSN Influence of Applying Phosphate Bio-fertilizers and Different Levels of Phosphorus Sources on the Productivity, Quality and Chemical Composition of Sweet Fennel (Foeniculum Vulgare Mill.) Zaki, M.F., A.A.M. Abdelhafez and Camilia Y. El-Dewiny 1 Department of Vegetable Res., National Research Centre, Dokki, 2 Department of Agricultural Microbiology, Fac. Agric. Ain Shams Univ., Department of Soils and Water Use, National Research Centre, Dokki, Cairo, Egypt. 3 Abstract: Attention has been focused on the use of organic natural substances and bio-fertilizers in farming due to the pollution factor and high costs of mineral fertilizers. Therefore, field trials were conducted in newly reclaimed soil during two successive winter seasons (2007/2008 and 2008/2009) at El-Nobaria region, Beheira Governorate, Egypt, to study the effect of different levels of two phosphorus sources and phosphate bio-fertilizers on vegetative growth, yield, quality and nutrients uptake by sweet fennel. Phosphate bio-fertilization included three treatments, (I) without bio-fertilizer (control); (II) VA arbuscular mycorrhizae and (III) Bacillus megaterium. Five combinations of the two P sources,.i.e. rock phosphate (20.8 % P2O 5) and calcium super phosphate (15.5 % P2O 5) each supplying 40 units of P2O 5 /Fed. were examined. These are (a) 100% super P; (b) 75% super P + 25% rock P; (c) 50% super P + 50% rock P; (d) 25% super P + 75% rock P and (e) 100 % rock P. Results show that sweet fennel plants inoculated with VA mycorrhizae showed higher [vegetative growth parameters namely plant length, leaves number; bulb dimensions (thickness, width and length), as well as fresh and dry weight of leaves, bulbs and total plant; total green yield; physical bulb quality (flatten, cylinder and elongated shape ratios); nutritional value i.e. TSS and uptake of N, P and K] than the untreated plants. Moreover, plants un-inoculated with phosphate bio-fertilizer had higher content of total phenolic compounds. Phosphate sources and rates differed statistically in their effect on the vegetative growth of sweet fennel plants. Treatments where all phosphorus was applied as rock phosphate showed significant effect on the vegetative growth, yield and quality of bulbs and reduced total phenols, with the highest total soluble solids. Lower values of plant growth were obtained by applying 100% super P fertilizer. The results indicated that combined effect of bio-fertilization and rock phosphate treatments caused significant increases in vegetative growth, green yield, bulb quality and chemical contents. The highest vegetative growth, yield and quality as well as chemical contents were obtained by applying VA mycorrhizae combined with the rate of 100 % rock phosphate. Such treatment is environmentally safe where concentrations of both Cd and F in the obtained plants are within the permissible levels. Key words: Sweet fennel; rock phosphate; P mineral fertilizer; Phosphate bio-fertilizers; VA mycorrhizael fungi ; Bacillus megaterium; green yield and quality; total soluble solids; total phenols; phosphorus; Cadmium; Fluorine. INTRODUCTION Untraditional vegetable crops became recently of important in Egypt for exportation and local consumption. Sweet fennel is one of the promising new crops in Egypt. It is an important aromatic plant mainly used in beverages, pharmaceutical purposes, food industry, human consumption, animal fodder and cosmetic products as well as in confectioneries. There is a need to know which cultivar and P fertilizer rate are the most appropriate for a good quality. Therefore, it is important to increase its productivity through adoption of the proper culture practices among which is optimized fertilization. Sweet fennel develops an edible bulb, a thickened base of leaves, which is becoming increasingly popular as a specialty vegetable in the United States (Simon, 1990). Marketed for many years in Europe, the bulbs are either consumed fresh, or prepared by baking, blanching, or boiling. In the United States, the bulbs are marketed as anise because of the high Corresponding Author: Zaki, M.F., Department of Vegetable Res., National Research Centre, Dokki, 334

2 concentration of anethole and methyl chavicol (estragole), components in the essential oil responsible for the anise aroma. Phosphorus has an important role in producing energy in various metabolic processes. Phosphorus deficiency causes important nutritional problems in new reclaimed soils Abd El-Salam et al. (2005). Phosphorus availability in the soil depends considerably on its concentration in the soil solution. The concentration of P in the soil solution is very low and can differ widely depending on the soil properties. The low availability of phosphorus to growing plants in arid and semi-arid regions is a general problem. In addition, the efficiency of phosphate fertilizers was found to be low and was generally attributed to phosphate retention phenomenon by soil components. This reaction is generally affected by many soil factors such as ph, clay minerals, reactive surface containing some components as iron and aluminum oxides, calcium carbonate and surface area of calcium carbonate particles, through its effect on soil reaction (ph), its reactive surface and as a source of the common ion, exerts a dominant effect on the nature and properties of phosphate in calcareous soils (Wahba et al., 2004). Most of the areas that have been put under reclamation and planned to be cultivated in Egypt are sandy and calcareous soils with alkaline ph. Under such conditions, considerable amounts of the available forms of phosphorus are usually subjected to rapid transformation to less available or unavailable forms. Therefore, the heavy application of phosphate fertilizers is a routine work necessary to supply the plant with the required amount of phosphorus (Mehana and Abdul Wahid, 2000). Rock phosphate is the main source of phosphate fertilizers. Residual effect of phosphorus plays an important role on growth, yield and quality of many crops. In this concern, Abd El-Salam (1999) in his study on sweet fennel plants found that, increasing phosphorus rates caused an increase in plant height, number of branches/plant, dry weight of different plant organs and the mineral (N, P and K) uptake. Wani and Konde (1998) found that, applying rock phosphate for garlic enhanced plant height, plant dry weight and the uptake of N and P. Abou El-Salehein and Ahmed (1998) stated that, applying rock phosphate at the rate of 100 Kg P2O 5/fed. enhanced the development of the vegetative growth (plant height and dry matter accumulation) and chemical contents of N, P and K elements of snap bean plants. Abou Zeid et al. (2005) found that, volatile oil yield and seed yield of fennel were increased by using calcium super phosphate (15.5% P2O 5) at a rate of 100 Kg/fed. The use of phosphate bio-fertilizers has been recommended by several researchers to partially compensate, chemical fertilizer in order to achieve clean agriculture with minimum pollution. Therefore, many investigators have successfully used phosphate bio-fertilizers of bacterial and fungal origin to increase the availability of immobilized phosphate and thus, minimize the use of mineral fertilizers. Several published studies showed the importance of certain soil microorganisms in increasing the availability of phosphorus in soils. Vesiculararbuscular mycorrhizae (VAM) are type of fungi that interact with numerous plant species and produce vesicles and arbuscules in root tissue along with extraordinary hyphae in the soil. These structures improve the ability of the roots for nutrients and water uptake and increase the attainment of ions which are slow diffusing ions through the soil (Barea, 1991). More importantly, VA mycorrhizal fungi are capable of dissolving weakly soluble soil minerals, especially phosphate, by releasing acids (Leyval and Berthelin, 1989) or increasing CO 2 partial pressure (Knight et al., 1989). Therefore, they have the ability to enhance host plant uptake of relatively immobile nutrients particularly P and Zn (Thompson, 1987). In addition, mycorrhizal hyphae can provide access to insoluble nutrient sources through enzyme activity or some physical or chemical modification of the rhizosphere (Hetrick, 1989).In other study Abdou et al. (2004) recommended supplying fennel plants with NPK at rate of 200, 300 and 100 kg/feddan, respectively, plus high level of phosphorein, a microbial phosphate solubilizer to maximize the vegetative growth and reduce rates of mineral fertilizers. Moreover, Darzi et al. (2006) found that the interactions of two factors of mycorrhizal inoculation (phosphate solubilizer fungi) and phosphate bio-fertilizing bacteria on 1000 seed weight and mycorrhizal inoculation and vermicompost on harvest index were significant. Also, Badran and Safwat (2004) reported that all biofertilizer treatments produced higher essential oil yields over the control treatment in both seasons. However, the Azotobacter + B. megaterium treatment was superior to other treatments and produced the highest yield (33.1 and 35.1 litres vs and 29.0 litres for the control plants in the two seasons) Mahfouz and Shamf-Eldin (2007) found that application of a mixture of Azotobacter chroococcum, Azospirillum liboferum, and Bacillus megatherium combined with chemical fertilizers (50% of the recommended NPK dosage) increased vegetative growth (plant height, number of branches, and herb fresh and dry weight per plant) of fennel plants compared to chemical fertilizer treatments only. Also, addition of biofertilizer with the chemical fertilizer increased these characters more than the half dose of chemical fertilizer alone. 335

3 To successfully grow sweet fennel in the newly reclaimed soils, many factors have to be considered, such as using the right cultivars, fertilization, compensating for the low amounts of available nutrients and low organic matter content as well as poor hydro-physical, chemical and biological properties of such soils. The best means of maintaining soil fertility and productivity could be done through periodic addition of the phosphorus natural sources such as rock phosphate and phosphate biofertilizer. Thus the aim of the present investigation was to study the possibility of using some bio-fertilizers combined with rates of rock phosphate and /or mineral phosphorus fertilizers (super phosphate 15.5% P2O 5) for satisfying the P requirements of sweet fennel crop and reducing environmental pollution caused by excessive use of chemical fertilizers. MATERIAL AND METHODS Two drip irrigated field experiments were carried out on sweet fennel (Foeniculum vulgare Mill, Family: Apiaceae) in a newly reclaimed soil at El-Noberia, Beheira Governorate, Egypt, during the two successive winter seasons of 2007/2008 and 2008/2009. The main analytical data of the soil are presented in Table (1), Page et al, 1982 and Klute, Table 1: Physical and chemical properties of the experimental soil during the two seasons of 2007/2008 and 2008/2009. A. Physical properties Season Sand % Silt % Clay % Soil texture 2007/ Sandy clay loam 2008/ Sandy clay loam B. Chemical properties Season E.C.(dS/m) ph OM(%) CaCO 3(%) Cations ( meq./l ) Anions ( meq./l ) Ca Mg Na K CO3 HCO3 Cl SO / Nil / Nil Seeds of sweet fennel (cv. Zefa Fino) were imported from Holland. Seeds were sown in foam trays filled st with a mixture of peat moss and vermiculite (1:1 volume) and grown in nursery on the 1 week of September. Seedlings were transplanted in the open field at 45 days age. Microbial Cultures and Biofertilizers Inoculation: Biofertilizer consists of one of the following two cultures (VA Mycorrhiza and Bacillus megaterium).vam inoculums consisted of 3 VA mycorrhizal strains; Glomus etunicatum, Glomus intraradices and Glomus monosporum. Mycorrhiza was applied alone at soil subsurface near the plant roots after two weeks from 0 transplantation. Bacillus megaterium was grown in batch cultures for 6 days period at C to reach late 4 exponential phase and achieve a cell suspension of 4 x 10 and added alone at a rate of 50 ml/seedling to the soil surface beside plants after two weeks from transplantation. Control plants were grown without biofertilizer. All biofertilizer cultures were kindly provided by the Unit of Bio-fertilizers, Faculty of Agriculture, Ain Shams University. Experimental Treatments and Design: Experimental Treatments were as follow: 1- Biofertilizer Treatments: Included three treatments. a) Without bio-fertilization. b) Inoculation with bio-fertilizer (VA Mycorrhiza fungi).and c) Inoculation with bio-fertilizer (Bacillus megaterium). 2- Phosphorus Sources Treatments: Phosphorus was applied at a rate of 40 units P2O 5 per feddan in five different combinations:- a) 100 % super phosphate (15.5% P2O 5), b) 75 % super phosphate + 25 % rock P, c) 50 % super phosphate + 50 % rock P, d) 25 % super phosphate+75 % rock P and e) 100 % rock P (20.5% P O )

4 Experimental Design: A split plots design with four replicates was followed. Biofertilizer treatments were located in the main plots, whereas the phosphatic sources rates were assigned in the sub-plots. The data of the experiment was tabulated and were subjected to statistical analysis according to Snedecor and Cochran (1980). The area of the 2 experimental plot was 15.0 m consisted of three rows, each row was 5.0 m length and 1m width and the planting distance was 50 cm apart. Seedlings were transplanted on two sides of each row. Fertilization: Nitrogen was added at a rate of 100 N units/fed. (50% poultry manure + 50% mineral fertilizer as ammonium nitrate 33.5% N) chemical analysis of applied manure is shown in Table 2. Potassium sulphate (48 % K2O) as a source of potassium at the rate of 40 K2O units/fed. was also applied. Taking into consideration that both phosphorus fertilizers and poultry manure were added as a basal dose to the soil, the other chemical fertilizers were splinted into three equal doses (30, 60 and 90 days after transplanting) beside the plants. Table 2: Chemical analysis of poultry manure in 2007/2008 and 2008/2009*. Mineral content (2007/2008) (2008/2009) N % P % K % C/N ratio D.M % O.C % Cd ppm F ppm Humidity% * Determined after Page, et al., (1982). Measurements: Microbial Counts: Soil samples were taken every 30 days, up to 120 days, to record the total microbial counts by plating on Nutrient agar (Difco Manual, 1977). B. megaterium was done by plate count on modified Alexzandrof medium (Zahra et al., 1984) and Bunt and Riviera medium (Zahra, 1969), respectively. The VA Mycorrhiza spore count and the percentages of root infection were estimated by the method described by Philips and Hayman (1970). Mycorrhizal spores were extracted by wet-sieving and decanting technique as described by Gerdemann and Nicolson (1963). Root Infection and Spore Numbers of Vesicular Arbuscular Mycorrhizae (VAM): The percentages of root infection with VAM in sweet fennel were estimated by the method described by Phillips and Hayman (1970). Mycorrhizal spores were extracted by wet-sieving and decanting technique as described Gerdemann and Nicolson (1963). Vegetative Growth Characters: A random sample of five plants was taken from each experimental treatment at 120 days after transplanting and the following data were recorded during the two seasons. 1) Plant height (cm). 2) Leaves number per plant. 3) Bulb dimensions (Length, width and thickness). 4) Leaves fresh weight (g/plant). 5) Bulbs fresh weight (g/plant). 6) Total plant fresh weight (g/plant). 7) Leaves dry weight (g/plant). 8) Bulbs dry weight (g/plant)and 9) Total plant dry weight. Iv) Yield, Quality and Components: I) Total Green Yield: All sweet fennel plants of each plot were harvested at maturing stage to record total green yield (Mg/ fed.). 2) Physical Bulb Quality: Flatten shape, cylinder shape and elongated shape ratios were calculated as follows: - Flatten shape ratio = W / T 337

5 - Cylinder shape ratio = L / (WT) Elongated shape ratio = L / W Aust. J. Basic & Appl. Sci., 4(2): , 2010 Where: W, width (cm); T, thickness (cm) and L, length (cm) (Pascale and Barbieri, 1995). 3) Nutritional Value: The following determinations were done in the bulbs at maturing stage. a- Total soluble solids (T.S.S.) was determined by a hand refractmeter, according to the method described by A.O.A.C (1980). b- Total phenols were determined by the Folin Ciocalteu reagent (Stratil et al., 2006). c- Nitrogen, phosphorus and potassium as plant nutrients and Cd and F as contamination were determined. 0 The dried plant samples (leaves and bulbs) at 70 C were digested with H2SO 4 and HClO 4 and analyzed for N, P, K and Cd as referred by Cottenie et al. (1982). Nitrogen was determined by the modified micro Kjeldah method. Phosphorous was determined colorimetrically by NH4-Metavanidate method. Potassium was estimated Flame-Photometrically and Cd was determined using Atomic-absorption. Fluorine was determined colorimetrically (Camilia El-Dewiny, 1992). RESULTS AND DISCUSSION I. Microbiological Determinations: A- Effect of bio-fertilization: The effect of bio-fertilizers on total microbial count during sweet fennel growth is shown in Table (3). It is clear from the data that bio-fertilizer has a profound effect on total microbial count under sandy soil conditions. The highest figures were generally in the treatments which received VA mycorrhizae. Addition of bio-fertilizer resulted in significant increase in total microbial flora in nearly all treatments. It is also clear that total microbial flora increased with plant growth reaching their highest figures at 120 days from transplantation. The highest figure was in the treatment receiving VA mycorrhizal inoculation. Figures of the second season showed the same trend of those observed in the first season. These figures are in accordance with those observed by Abdelhafez and Abdel-Monsief (2006), who reported that total microbial counts in the rhizosphere of cantaloupe and cucumber were significantly higher in the inoculated plants with VA mycorrhizal fungi than in the un-inoculated ones. Another study also showed that total mycorrhizal fungi count increased in the rhizosphere of Foeniculum vulgare Mill. when plants were inoculated with two arbuscular Table 3: Effect of bio-fertilization on total bacterial count, B. megaterium count, Mycorrhizal spore count and Mycorrhizal infection percentage during the two successive seasons (2007/2008 and 2008/2009). Bio-fertilizer Bacterial total count B. megaterium count Mycorrhizal spore count Mycorrhizal infection level ^ (x 10 6/g soil) ^ (x 10 5/g soil) /100 g soil of plants (%) Days of plantation Days of plantation Days of plantation Days of plantation First season ( ) Without bio-fertilizer Mycorrhizae B. megaterium L.S.D. at Second season ( ) Without bio-fertilizer Mycorrhizae B. megaterium L.S.D. at Moreover, the data in Table (3) show that B. megaterium counts followed the same trend of the total microbial flora where the highest counts were observed in the treatment which received B. megaterium. Also, the total count of B.megaterim increased with plant growth reaching their maximum at 90 days from transplanting. Furthermore, data presented in Table (3) indicate higher mycorrhizal spore counts and mycorrhizal infection percentage in the treatment which received mycorrhizal inoculation after 90 days from transplanting compare with other treatments. B) - Effect of Phosphatic Sources and Rates: Data in Table (4) showed that, their counts for both seasons increased with the increase of plant growth reaching their maximum after 120 days from transplanting. It is clear also that the treatment of 100 % rock 6 phosphate gave the highest figure reaching 10.2 x 10 /g dry soil for this treatment. Similar trends were recorded in the second season in different stages of plant growth. 338

6 Table 4: Effect of phosphate sources and rates on total microbial count, B. megaterium count, Mycorrhizal spore count and Mycorrhizal infection percentage during the two successive seasons (2007/2008 and 2008/2009). Phosphatic Bacterial total count B. megaterium count Mycorrhizal spore count Mycorrhizal infection level sources and rates ^ (x 10 6/g soil) ^ (x 10 5/g soil) /100 g soil of plants (%) Days of plantation Days of plantation Days of plantation Days of plantation First season ( ) 100% S.P.* %S.P.+25%R.P.** % S.P. + 50%R.P % S.P. + 75%R.P % R.P L.S.D. at % S.P % S.P. + 25%R.P % S.P. + 50%R.P % S.P. + 75%R.P % R.P L.S.D. at * S.P = Super phosphate ** R.P. =Rock Phosphate C) - Effect of Interaction: Data in Table (5) showed that the treatment receiving 100 % rock phosphate with Mycorrhizae inoculation gave significant differences in VA mycorrhizal spore count compared with other treatments. Bio-fertilization with mycorrhizae gave significantly higher microbial densities compared with similar treatment without biofertilization. The highest figures of micorrizal were observed after 90 days of transplantation in the treatment receiving 100 % rock phosphate. Figures obtained in the second season are in harmony with those of the first season with respect to bio and Rock P fertilization treatment and also for stages of plant growth. Table 5: Effect of the interaction between bio-fertilizers and phosphatic sources and rates on total microbial count, B.megaterium count, Mycorrhizal spore count and Mycorrhizal infection percentage during the two successive seasons (2007/2008 and 2008/2009). Bio- fertilizers Phosphatic Bacterial total count B. megaterium count Mycorrhizal spore count Mycorrhizal infection level sources and rates ^ (x 10 6/g soil) ^ (x 10 5/g soil) /100 g soil of plants (%) Days of plantation Days of plantation Days of plantation Days of plantation First season ( ) Without 100% S.P bio-ertilizer 75% S.P. + 25% R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P Mycorrhizae 100% S.P % S.P. + 25% R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P B. megaterium 100% S.P % S.P. + 25% R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P L.S.D. at N.S 0.29 N.S Second season Without 100% S.P bio-rtilizer 75% S.P. + 25% R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P Mycorrhizae 100% S.P % S.P. + 25% R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P B. megaterium 100% S.P % S.P. + 25% R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P L.S.D. at 0.05 N.S N.S * S.P = Super phosphate ** R.P=Rock Phosphate Table (5) also showed the effect of phosphate bio-fertilizers and phosphatic sources and rates treatments on the densities of bacterial total microbial count, B. megaterium, mycorrhizal spore count and mycorrhizal infection percentage in sweet fennel rhizosphere. It is clear from the data that B. megaterium follow the same trend as total microbial count with respect to both phosphate sources, rates and bio-fertilization treatments. Inoculation with B. megaterium resulted in a significant increase in their densities in both seasons and under different fertilization treatments. It is also clear that the densities of B. megaterium increased in the rhizosphere with the increase in plant growth reaching the highest figure after 90 days in all treatments for both seasons. The progressive increase in the densities of B. megaterium with plant growth indicates that the inoculated organism was able to establish itself in the rhizosphere of sweet fennel. 339

7 II. Vegetative Growth Characters: A- Effect of Bio-fertilization: Vegetative growth of sweet fennel plants expressed as plant height; leaves number/plant and bulb dimensions (thickness, width and length) as well as fresh and dry weight of leaves, bulbs and total plant were increased by applying VA mycorrhizal spore (Table, 6). Mycorrhizal treatment increased these characteristics as compared with the untreated plants or with the treated plants by B. megaterium. These increases were statistically significant and similar in the two seasons. These increases in vegetative growth might be due to the increases in the soil microbial flora which happened by bio-fertilization as it is shown in Table (3). Many investigators reported that bio-fertilization increased growth of sweet fennel plants (Abdou et al., 2004; Badran and Safwat, 2004; Rupam et al., 2004; Darzi et al., 2006; Mahfouz and Shamf-Eldin, 2007). Rupam et al. (2004) found that two arbuscular mycorrhizal (AM) fungi Glomus macrocarpum and Glomus fasciculatum significantly improved growth of Foeniculum vulgare Mill. Darzi et al. (2006) on fennel reported that the highest values of vegetative growth were obtained through mycorrhization. Table 6: Effect of Bio-fertilizers on vegetative growth of sweet fennel after 60 days from transplantation during the two successive seasons (2007/2008 and 2008/2009). Bio-fertilizers Plant Leaf No. Bulb dimensions(cm ) Fresh weight (gm/ plant) Dry weight ( gm/ plant) height (cm) Thick- Width Length Leaves Bulbs Total Leaves Bulbs Total ness First season Without bio Mycorrhizae B.megaterium LSD at N.S Second season Without bio Mycorrhizae B..megaterium LSD at N.S B- Effect of Phosphatic Sources and Rates: The highest vegetative growth of sweet fennel plants expressed as plant height, leaves number and bulb dimensions (thickness, width and length) as well as fresh and dry weight of leaves, bulbs and total plant was obtained by the application of 100 % rock P treatment followed by plants which received 25 % super P +75 % Rock P (Table, 7). In contrast, low values of plant growth were obtained by 50% super P + 50% Rock P, 75% super P + 25% Rock P or 100super P in a descending order. These results were true and similar in the two seasons of study. These increases in the vegetative growth might be due to the increase in the soil microbial count (Tables 3 and 4). Data also, indicated that rock phosphate fertilizer had a profound effect on total microbial count under sandy soil conditions. Tables (4 and 7) show that the highest microbial count and the highest vegetative growth were correlated with 100% rock P treatment. Many investigators reported Table 7: Effect of phosphorus sources and rates on vegetative growth of sweet fennel after 60 days of transplantation during the two successive seasons (2007/2008 and 2008/2009). Phosphatic Plant Leaf No. Bulb dimensions(cm ) Fresh weight (gm/ plant) Dry weight ( gm/ plant) sources and height rates (cm) Thick- Width Length Leaves Bulbs Total Leaves Bulbs Total ness First season % S.P %S.P. +25%R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P LSD at Second season ( ) 100% S.P %S.P. +25%R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P LSD at * S.P = Super phosphate ** R.P = Rock Phosphate 340

8 generally that, rock phosphate fertilizer increase vegetative growth of vegetable crops (Abou El-Salehein and Ahmed, 1998 on snap bean; Wani and Konde, 1998 on garlic; Kandil, 2002 on fennel and Abdelhafez and Abdel-Monsief, 2006 on cantaloupe and cucumber). Wani and Konde (1998) found that, applying rock phosphate of garlic enhanced plant height and plant dry weight. Abou El-Salehein and Ahmed (1998) stated that, the treatment of rock phosphate at the rate of 100 Kg P2O 5/fed enhanced the development of the vegetative growth (plant height and dry matter accumulation) of snap bean plants. C- Effect of Interaction: The obtained data revealed that the interaction treatments (Table, 8) significantly affected all growth parameters. These results were true and nearly similar in both seasons of the experiment. Generally, it could be summarized that, the highest plant height and bulb dimensions (thickness width and lenght) as well as fresh and dry weight of leaves, bulbs and total plant of sweet fennel were recorded with bio-fertilization combined with 100 % rock P treatment in the two seasons of study. In general, the highest values of vegetative growth of sweet fennel were obtained by the combined effect of phosphate bio-fertilizer (VA mycorrhizal) and 100 % rock-p fertilizer. These results were the reflection of the high microbial flora in the soil of the treatment receiving this treatment as it is shown in Tables (5). On the contrary, the lowest vegetative growth was obtained by treatment receiving 100% mineral phosphorus fertilizer without bio-fertilization in the first and second season. These results are in agreement with those obtained by Rupam et al. (2004) on fennel found that two arbuscular mycorrhizal (AM) fungi Glomus macrocarpum and Glomus fasciculatum significantly improved growth of Foeniculum vulgare Mill. However, AM inoculation of plants along with phosphorus fertilization significantly enhanced growth of plants compared to either of the components applied separately. Darzi et al. (2006) found that the interactions of two factors of mycorrhizal inoculation and phosphate biofertilizer on vegetative growth of fennel were significant. Table 8: Effect of interaction between bio-fertilizers and phosphorus sources and rates on vegetative growth of sweet fennel at harvest during the two successive seasons (2007/2008 and 2008/2009). Bio-fertilizers Phosphatic Plant Leaf No. Bulb dimensions(cm ) Fresh weight (gm/ plant) Dry weight ( gm/ plant) sources and height rates (cm) Thick- Width Length Leaves Bulbs Total Leaves Bulbs Total ness First season Without bio- 100% S.P %S.P. +25%R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P Mycorrhizae 100% S.P %S.P. +25%R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P B. megaterium 100% S.P %S.P. +25%R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P LSD at N.S N.S Second season Without bio- 100% S.P %S.P. +25%R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P Mycorrhizae 100% S.P %S.P. +25%R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P B. megaterium 100% S.P %S.P. +25%R.P %S.P. + 50% R.P % S.P.+ 75% R.P % R.P LSD at N.S N.S * S.P = Super phosphate ** R.P. Rock Phosphate III. Total Green Yield, Quality and Components: A- Effect of Bio-fertilization: Results in Table (9) Showed that there were significant differences in the total green yield of sweet fennel plants between phosphate bio-fertilizers treatments in the two seasons of study. Total green yield of the phosphate bio-fertilizer (VA mycorrhizal) treatment recorded higher values compared with other treatments. Bio-fertilization resulted in statistical increases in the total green yield of sweet fennel. Increase in the total green yield due to bio-fertilization might be due to its positive effect on the vegetative growth and chemical content of sweet fennel plants (Tables 6 and 9) Treatment of VA mycorrhizal resulted in statistical increases 341

9 Table 9: Effect of bio-fertilizers on total green yield, physical bulb quality, nutritional value, macro-nutrients uptake and contaminants content in leaves and bulbs of sweet fennel at harvest during the two successive seasons (2007/2008 and 2008/2009). Bio- Total Physical bulb quality Nutritional value Macro-nutrients uptake (g/plant -1 Contamination content (ug g ) fertilizers green yield Flatten Cylinder Elongated T.S.S Phenols N P K Cd F (Mg/fed.) shape shape shape (%) (mg/g) ratio ratio ratio L B L B L B L B L B First season ( ) Without bio Mycorrhizae B.megaterium LSD at N.S N.S. N.S N.S. Second season ( ) Without bio Mycorrhizae B.megaterium LSD at N.S N.S. N.S N.S. * L= Leaves ** B = Bulbs in the total green yield of sweet fennel. This increase in the total green yield due to inoculation with VA mycorrhizal amounted to and ton/fed which equals and % of the control (noninoculation) in the two seasons, respectively. These findings were similar and true in both seasons of study. These results were in agreement with those obtained by Rupam et al. (2004) on fennel; Abdelhafez and Abdel- Monsief (2006) on cantaloupe and cucumber and Darzi et al. (2006) on fennel. B- Effect of Phosphatic Sources and Rates: Data presented in Table (10) indicated that application of 100 % rock P treatment increased the total green yield of sweet fennel. On the contrary, the lowest values of total green yield were obtained by application 100% mineral P fertilizer (Control). The rate of 100 % rock P resulted in statistical increases in the total green yield of sweet fennel amounted to and Mg/fed which equals and % of the rate 100 % super P fertilizer in the first and second seasons, respectively. These results might be due to the increases in vegetative growth and mineral content of the plants of this treatment. Increases also, might be due to the increases in the soil flora which happened by bio-fertilization as it is shown in Table (4). These results were completely similar in both seasons. These results were in agreement with those obtained by Abd El-Salam (1999) and Abou Zeid et al. (2005) on fennel. Table 10: Effect of phosphorus sources and rates on total green yield, physical bulb quality, nutritional value, macro-nutrients uptake and contamination content in leaves and bulbs of sweet fennel at harvest during the two successive seasons (2007/2008and 2008/2009). Phosphatic Total Physical bulb quality Nutritional value Macro-nutrients uptake (g/plant -1 Contamination content (ug g ) sources green and rates yield Flatten Cylinder Elongated T.S.S Phenols N P K Cd F (Mg/fed.) shape shape shape (%) (mg/g) ratio ratio ratio L B L B L B L B L B First season ( ) 100% S.P %S.P.+25%R.P %S.P.+50%R.P %S.P.+75%R.P % R.P LSD at Second season ( ) 100% S.P %S.P.+25%R.P %S.P.+50%R.P %S.P.+75%R.P % R.P LSD at * L= Leaves ** B = Bulbs C- Effect of Interaction: Interaction of bio-fertilization with phosphatic sources rates statistically affected on total green yield of sweet fennel is shown in Tables (11). These results held well in the two experimental seasons. Generally, it could be concluded that, the highest total green yield of sweet fennel plants was recorded by the combined effect of phosphate bio-fertilizer (VA mycorrhizal) treatment and the rate of 100 % rock P in the two seasons of study. On the contrary, the lowest total green yield of sweet fennel plants was recorded by the combined effect of non-inoculation plants with bio-fertilizer and 100% super P fertilizer treatment in the two seasons of study. These results held well in the two seasons of study. These results were in agreement with those obtained by Rupam et al. (2004) on fennel found that VAM inoculation of plants along with phosphorus fertilization significantly enhanced yield compared to either of the components applied separately. Darzi et al. (2006) found that the interactions of two factors of mycorrhizal inoculation and phosphate biofertilizer on yield of fennel were significant. 342

10 Table 11: Effect of interaction between bio-fertilizers and phosphorus sources and rates on total green yield, physical bulb quality, nutritional value, macro-nutrients uptake and contamination content in leaves and bulbs of sweet fennel at harvest during the two successive seasons (2007/2008and 2008/2009). Bio- Phosphatic Total Physical bulb quality Nutritional value Macro-nutrients uptake (g/plant -1 Contamination content (ug g ) fertilizers sources green and rates yield Flatten Cylinder Elongated T.S.S Phenols N P K Cd F (Mg/fed.) shape shape shape (%) (mg/g) ratio ratio ratio L B L B L B L B L B First season ( ) Without bio- 100% S.P %S.P.+25%R.P %S.P.+50%R.P %S.P.+75%R.P % R.P Mycorrhizae 100% S.P %S.P.+25%R.P %S.P.+50%R.P %S.P.+75%R.P % R.P B. megaterium 100% S.P %S.P.+25%R.P %S.P.+50%R.P %S.P.+75%R.P % R.P LSD at N.S Second season Without bio- 100% S.P %S.P.+25%R.P %S.P.+50%R.P %S.P.+75%R.P % R.P Mycorrhizae 100% S.P %S.P.+25%R.P %S.P.+50%R.P %S.P.+75%R.P % R.P B. megaterium 100% S.P %S.P.+25%R.P %S.P.+50%R.P %S.P.+75%R.P % R.P LSD at N.S. N.S. N.S IV - Physical Bulb Quality and Nutritional Value: A. Effect of Bio-fertilization: Data in Table (9) show that there were significant differences in flatten and elongated shape ratios; total soluble solids (TSS) and total phenols by using different phosphate bio-fertilizers treatments in the two seasons of study. Bio-fertilization with VA mycorrhizal caused significant decreases in flatten shape ratio and increases in cylinder and elongated shape ratios of sweet fennel bulbs, but this increase in cylinder shape was not statistically significant in the two seasons. The depression in the flatten shape bulbs means that bio-fertilized bulbs tended to be round in shape more than flattening, the decrease in cylinder shape ratio and increase in elongated shape bulbs means increases in the round bulbs, this is considered an improvement in quality of fennel bulbs. These results indicated that bio-fertilization increased the exportable yield of sweet fennel crop (El-Shakry, 2005). Higher values of flatten shape ratio and lower values of elongated shape were recorded by non-inoculated plants followed by B. megaterium treatment. These results were similar in the two seasons. These results were in accordance with those reported by Fawzy, et al. (2006). VA mycorrhizal increased total soluble solids and decreased total phenolic-compounds (glycosides) content of sweet fennel bulbs. The higher values of total phenols content were obtained by B. megaterium treatment followed by non-inoculated plants, compared with VA mycorrhizae treatment. Similar results were obtained by Khalil et al. (2007). B. Effect of Phosphatic Sources and Rates: Data in Table (10) indicated that application of 100 % rock P treatment improved the physical bulb quality; total soluble solids TSS and total phenols of sweet fennel bulbs because it decreases in flatten and cylinder shape ratios and increase in elongated shape bulbs, increases in TSS and total phenols, this is considered an improvement in quality of fennel bulbs. On the contrary, the lowest values of physical bulb quality; total soluble solids TSS and total phenols of sweet fennel bulbs were recorded by 100 % mineral P treatment. These findings were similar and true in both seasons of study. C. Effect of Interaction: Interaction among phosphate bio-fertilization with phosphatic sources and rates statistically affected on physical bulb quality and total phenols of the bulbs (Table 11). TSS in the two seasons and cylinder and elongated shape ratios of sweet fennel bulbs in the second season did not statistically affect by this interaction. 343