الفهرس 
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Abstract
Faba bean (Vicia faba L.) is considered as an old legume food grows on large areas in the world. The crop has great nutritional value for both human and animal. Root rot and wilt diseases are the most important diseases affecting faba bean plants in Egypt causing considerable reduction in seed yield and quality.The Present work aimed to evaluate the biotic and abiotic inducers as well as efficiency magnetized water and seeds on incidence of root rot and wilt diseases of faba bean and investigate the effect of some factors which affect the efficiency of PGPR strains for suppressing the diseases.Results of the study can be summarized as follows: 1. Thirty-eight isolates of different soil-borne fungi (14 of R. solani, 4 of F. solani, 7 of F. oxysporum, 3 of M. phaseolina and 10 of Fusarium spp.) were isolated from wilted and rotten roots of faba bean plants collected from different locations in New Valley governorate.2. The isolated fungi proved to be pathogenic to Masr 1 faba bean cv. under greenhouse conditions. F. oxysporum isolates caused wilt disease, however, isolates of R. solani, M. phaseolina and other Fusarium species caused root rot. Virulence of isolates on the tested faba bean cv. Misr 1 was different. The highly pathogenic fungal isolates R. solani (isolate No. 8), F. solani (isolate No. 1), M. phaseolina (isolate No. 1), the incitant of root rot and isolate No. 1 of F. oxysporum, the incitant of wilt.3. Thirteen faba bean cultivars were tested for their susceptibility to infection root rot and wilt diseases. All tested cultivars were varied in susceptibility to infection with the tested pathogenic fungi. All tested cultivars were highly susceptible to infection with R. solani. Giza 3, Giza 40, Giza 429, Giza 716, Giza 843 Misr 1 and Nubria 2 were highly susceptible to infection with F. solani but Nubria 3 only was resistance. Giza 40, Giza 429, Misr 1, Misr 3, Sakha 1 and Nubria 3 were highly susceptible, while, Wadi 1 and Nubria 1 were resistance. All tested cultivars were highly susceptible to infection by F. oxysporum except Giza3, Nubria 3 and Giza 716 were susceptible.
4. All the tested chemical inducers have no effect or little effect on linear growth of all tested pathogenic fungal isolates. 5. All tested chemical inducers at different concentrations especially at high concentration were decreased the root rot and wilt severity. Salicylic acid at 400 and Bion at 1000 ppm recorded the lowest root rot and wilt severity.
6. All chemical inducers individually or in combination with R. leguminosarum significantly decreased root rot and wilt diseases under greenhouse and field conditions as well as increased total yield /feddan under field conditions. The combination between chemical inducers and R. leguminosarum more effective for controlling root rot and wilt diseases and increased seed yield/feddan than individually treatment. Application of SA and Bion + R. leguminosarum recorded the lowest percentage of root rot and wilt severity and the highest plant growth and yield parameter during both growing seasons.7 All tested abiotic inducers either individually or combined with R. leguminosarum were increased the enzymes activities viz. peroxidase (POX), polyphenoloxidase (PPO), phenylalanine ammonia lyase (PAL), catalase (CAT), superoxide dismutase (SOD) and PR proteins (ß -1, 3- glucanase and chitinase) as well as total phenols, total flavonoids and lignin contents in faba bean plants. The combination between chemical inducers and R. leguminosarum increased the activities of all tested enzymes, total phenols, flavonoids and lignin contents. The highest activities were recorded when faba bean seeds treated with the SA or Bion combined with R. leguminosarum. 8. Cell cultures, extracellular metabolites, volatile metabolites of all tested PGPR strains were suppressed the linear growth of all tested pathogenic fungi in vitro. Ps. fluorescens followed by B. megaterium were more active than B. subtilis and B. cereus in reduction of the tested fungi redial growth.
9. All PGPR stains were able to produce IAA, HCN, siderophore, Ammonia in media growth. Ps. fluorescens produced the highest levels of cyanide hydrogen and ammonia followed by B. subtilis, while the higher level of IAA was produced by B. subtilis followed by Ps. fluorescens. Also, B. megaterium was the most PGPR strain produced siderophore followed by Ps. fluorescens. All the tested PGPR strains successfully solubilized inorganic phosphate on Pikovskya’s agar medium. Also, all plant growth promoting rhizobacteria strains (PGPR) were able to produce mycolytic enzymes viz. cellulase, chitinase β-1,3-glucanase, amylase and protease except B. cereus and B. megaterium not able to produce protease and amylase. B. megaterium recorded the highest activities of chitinase, β-1,3-glucanase, while, B. cereus produced the lowest levels of all tested enzymes. 10.Application of PGPR gave a great reduction in root rot and wilt severity under greenhouse and field conditions as well as significantly increase in plant growth parameters and yield components in faba bean plants under field conditions during two growing seasons. The combinations between any PGPR strains and R. leguminosarum more effective for controlling the diseases and increased seed yield than individually application. Treatment B. cereus + R. leguminosarum and Ps. fluorescens + R. leguminosarum recorded the lowest root rot and wilt severity and the highest total seed yield/feddan) under greenhouse and field conditions. 11.All PGPR strains formulated on DPLC gave the highest effect in decreasing root rot and wilt severity and increased seed yield/feddan than formulated on other carriers under greenhouse and field conditions. Ps. fluorescens formulated on any tested carriers especially DLPC formulation gave the best results in this respect. 12. The initial populations of all 4 PGPR strains were higher in irradiated DPLC powder formulations than the other formulations. The population densities declined over time in four formulations during the ten months storage at 4°C. All tested PGPR strains grown on DPLC formulation were stayed viable even up nine months except B. subtilis was remained valid until the seventh month. 13. All tested PGPR strains (biotic inducers) either individually or combined with R. leguminosarum were increased the oxidative enzymes viz. PO, PPO, PAL, CA, SOD and PR proteins (ß -1, 3- glucanase and chitinase) as well as total phenols, total flavonoids and lignin contents in faba bean plants. The combination between PGPR strains and R. leguminosarum were increased the activities of all tested enzymes, PR-protein, total phenols, flavonoids and lignin contents. The highest activities were recorded in combination of Ps. fluorescens + R. leguminosarum followed by Ps. fluorescens individually.14.Magnetized faba bean seeds grown in pots under artificial soil infestation and in field under natural infection with back history of infestation with the tested fungi and irrigated with magnetized tap water or agricultural drainage water were decreased root rot and wilt severity under saline soil and water conditions at newly reclaimed land in New Valley govenorate. The combination of magnetized faba bean seeds and irrigated with magnetized tap water recorded the lowest disease severity. While under soil and water conditions in Assuit governorate, magnetized tap water or magnetized seed give no effect on reduction of root rot and wilt severity. 15.Under field conditions, faba bean grown from magnetized seeds and irrigated with magnetized tap water recorded the highestseed yield during both growing seasons.
16. The enzymes viz. peroxidase, polyphenoloxidase, phenylalanine ammonia lyase, catalase, superoxide dismutase and PR- protein (chitinase and β-1,3 glucanase) were increased in faba bean plants grown from magnetized seeds and irrigated with magnetized water.