Greenhouse experiment was conducted to evaluate the pathogenicity of root rot fungi on faba bean plant. Lab. experiment was also conducted to study the effect of organic compounds and fungicide Rizolex-T50 on the linear growth of the tested pathogenic fungi. Two field experiments were also carried out to study the effect of organic compounds with different concentrations and fungicide Rizolex-T50 on reduction of root rot and enhancing some morphological, physiological characteristics and productivity of faba bean under saline affected soil conditions during 2013/2014 and 2014/2015 seasons. The results under greenhouse conditions indicated that all tested pathogenic fungi caused emergence damping-off. Rhizoctonia solani was the most effective in pre-emergence damping-off while, Fusarium solani gave the highest percentage of post-emergence damping-off. The pathogenic fungi caused anatomically deformation in root structure. Infected root with F. solani caused complete destruction of epidermal cells followed by degradation of cell wall in the cells of cortex. In vitro, Rizolex-T50 completely inhibited the growth of the tested pathogenic fungi. On the other hand, chitosan at 8 g/L was the most effective in reducing fungal growth followed by proline at 200 ppm. In vivo, the application of organic compounds counteracted the harmful effects of salinity. Humic acid highly reduced pre-and post-emergence damping-off and subsequently increased field emergence %. The high level of proline (200 ppm) was more effective in increasing morphological measurements (plant height, No. of branches and leaves/plant) and photosynthetic pigments i.e. chlorophyll a, b and carotenoids. While, the high concentration of HA (2000 ppm) significantly increased No. of pods/plant, seed yield/plant and 100-seed weight. Chitosan gave the highest phenols content followed by proline treatment. The high increase in carbohydrate content occurred under low level of HA (1000 ppm), followed by high level of proline (200 ppm). The efficacy of the tested organic compounds in control of root rot disease was reflected on the plant causing increase in yield components. It is suggested that pre-sowing seed soaking with HA (2000 ppm) or chitosan (8 g/L) or proline (200 ppm) could be considered as alternative fungicide for controlling root rot disease and increasing productivity of faba bean under salinity and natural infection conditions in the field.

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Laboratory and filed experiments were conducted in 2005/2006 and 2006/2007 winter seasons to study the effect of some nutritional elements (ferrous, zinc, manganese and calcium) at 2, 4, 6 and 8 g/L on chocolate spot and rust diseases of faba bean. The laboratory results, declared that zinc and manganese at 6 g/L completely inhibited the linear growth and sporulation as well as mycelial dry weight of Botrytis fabae. However, ferrous at 2 g/L or calcium at 8 g/l has no effect on neither linear growth nor mycelial dry weight.The results of field experiment show that calcium at 6 g/L led to maximum reduction of chocolate spot and rust diseases severity followed by manganese at 4 g/L then zinc at 4 g/L. The highest value of plant height occurred under zinc at 4 g/L followed by 6 g/L calcium which increased significantly number of branches/plant. There was positive relationship between number of pods/plant and calcium levels treatment from 2-6 g/L. Calcium at 6 g/L and 4 g/L gave the highest values of 100seed weight followed by manganese 4 g/L.Total phenol contents reached their maximum when faba bean sprayed with 2 or 4 g/L calcium followed by ferrous (6 g/L) then manganese (6 g/L). Also, the highest concentrates of chlorophyll a, b and caroteinoids occurred under the application of calcium at 2 g/L.It is clear from this study that there is no significant differences between the efficacy of calcium at 4 or 6 g/L and Diathine M-45 also between manganese (4 g/L) or calcium (6 g/L) and Plantvax 20% EC effects in reducing faba bean chocolate spot and rust diseases, respectively.In general, some of nutritional elements are promising trend in controlling of chocolate spot and rust diseases of faba bean, where it decreased the infection, environmental friendly and coast effective compared with the ordinary fungicides.

Detection of cowpea rust disease was carried out in 13 distracts of Dakahlia governorate. The high disease incidence was in Sherbin distract followed by Tmai Elamdid distract. While, the low disease incidence was in Aga distract. On the other side, the high value of disease severity occurred under Tmai Elamdid, Mit Salsyl and Bilqas distracts. While, Minit Elnasr distract was came late.Foliar application of microelements at all tested concentrations and also fungicide (Plantvax 20% EC 1m/l) significantly decreased the infection with Uromyces vignae. The best results were obtained from boron at 0.05 g/l followed by manganese 3 g/l then ferrous 3 g/l.All tested microelements caused significant increase in plant height and number of branches, leaves and pods/plant. The low concentration was more effective than the higher one except ferrous which gave the reverse. While there was no significant effect due to fungicide treatment on these parameters. The highest values of 100-seeds weight occurred under boron application at 0.05 g/l followed by manganese at 3 g/l then boron 0.025 g/l.The high total phenol content in cowpea leaves were obtained from the application of boron at 0.05 g/l followed by manganese at 3 g/l then manganese 2 g/l. In all tested microelements treatment a significant increase in chlorophyll a, b and caroteinoids content was achieved compared with fungicide and check treatments. This study indicates that, there is a correlation between induced resistance for rust disease and accumulation of phenols.

Lupine is cultivated in Egypt for food, medical and industrial purposes. Root rot diseases caused by several soil-borne fungal pathogens are among the most destructive diseases attacking lupine plants. Greenhouse and field experiments were conducted to study the effect of hydrogen peroxide (H2O2) and acetylsalicylic acid (ASA) in addition to Rhizolex-T50 on lupine root rot disease, growth, certain physiological activities and productivity of lupine. Lupine seeds (cvs. Giza 1 and Giza 2) were examined. The data indicated that isolation of pathogenic fungi from both cultivars of diseased lupine was carried out in five locations of Dakahlia governorate. The high frequency isolated fungi presented in Temi El-Amdeed followed by Bani-Ebeed location. Fusarium solani and F. oxysporum proved to be the most dominate isolated followed by Rhizoctonia solani. In greenhouse, Giza 1 was high susceptible cultivar for infected with root rot pathogenic fungi. Sclerotium rolfsii followed by R. solani whereas F. solani was the most aggressive damping-off disease. In the field experiment, Giza 2 cultivar was the best in germination% and more tolerant of damping-off than Giza 1. The application of Rhizolex-T50 followed by H2O2 at low concentrate (0.50 mM) showed a highest percentage of germination within lowest percentage of damping-off. No significant differences between Rhizolex-T50 and H2O2 at 0.50 mM were detected. The high photosynthetic pigments and phenolic content were obtained from the application of ASA at moderate concentrate (15 mM) in both cultivars. Giza 2 gave the highest values in these parameters. Soaking in both tested materials increased significantly growth parameter examined, yield components and seed quality. The moderate concentration of ASA (15 mM) was the most effective followed by the low concentration of H2O2 (0.50 mM). Could be concluded that the application of H2O2 at 0.50 mM and ASA at 15 mM as seed soaking could be considered as fungicide alternatives for controlling lupine root rot disease as well as improve growth and productivity.