الفهرس 
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Abstract
SUMMARY
·This investigation aimed at investigating the role of vascular
arbuscular Mycorrhizae in controlling damping-off and root-rot diseases of
faba bean plants (Vida faba L.) under sterilized and unsterilized soil in
the greenhouse. The effect of the two species of VA-Mycorrhizal fungi
and Rhizobium (Rhizobium leguntinosarunn was also studied. Seed
dressing with fungicides and fertilization with phosphate and their effects
on VA-Mycorrhizal fungi and its role in controlling damping-off and rootrot
diseases were studied.
The results could be summarized as follows:-
1- The fungi isolated from infected roots of plants collected from the r’ann
of Faculty of Agriculture at Moshtohor, were Fusarium solani (Mart.)
and Rhlzoctonia solani (Kuehn).
2- R. solani was the most virulent pathogen causmg pre-emergence
damping-off and root-rot followed by F. solani.
3- Infection by R. solani pathogen decreased the plant height and root
length of the Giza 2 and Ribaya 40 cultivars more than infection with
F. solani. Also, it reduced the fresh and dry weight of roots and shoots,
number of leaves and nodulation especially in the sterilized soil. This was
more evident in Rihaya 40 than Giza 2.
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4- Ribaya 40 cultivar grown in sterilized soil showed the lowest
percentages of healthy survival plants ill uninoculated or inoculated soil
with the pathogenic fungi and also in unsterilized or sterilized soil
compared with Giza 2 cultivar.
5- Addition of VA-Mycorrhizae increased the percentage of healthy
survival plants and decreased the percentage of root-rot disease of faba
bean plants with the presence of F. solanl or R. solani pathogen than
those inoculated with F. solani or R. solani only.
6- Addition of VA-Mycorrhizae increased plant height, root length, shoot
and root my matter in the presence or absence of infection with F. solaui
or R. solani.
7- Effect of Glomus australe all plant growth was higher than Glomus
macrocarpum especially in the presence of infection with F. solani or
R. solani.
8- Addition of VA-Mycorrbizae to soil-increased the root colonization ~ . -~
with VA-Mycorrhizae in case of the sterilized soil more than in the case of
the unsterilized soil. The number of VA-Mycorrhizae arbuscules,
vesicules and mycelium in the case of inoculation with G. macrocarpum
was higher than in the case of inoculation with G. australe.
9- Infection with R. solani reduced the number of VA-Mycorrhizae
colonization in root. Infection with F. solani increased the number of
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VA-Mycorrhizae 111 roots especially III case of soil inoculation with G.
australe.
10- The percentage of healthy survival plants in plants previously
inoculated with R. leguminosarum was lower than with uninoculated
plants especially in the sterilized soil. The percentage of root-rot was not
affected by R. leguminosarum inoculation.
11- Addition of VA-Mycorrhizae and inoculation with R. leguminosarum
increased the percentage of healthy survival plants and reduced the
percentage of root-rot infection in the presence or absence of F. solani or
R. solani.
12- Addition ofVA-Mycorrhizae and inoculation with R. leguminosarum
increased root length and the number of nodules / plant in case of Giza 2
cv., whereas they increased the root length, root dry matter, No. of leaves
and N. of nodules / plant in case ofRibaya 40 cv.
13- Dual inoculation with VA-Mycorrhizae (G. macrocarpum or G.
australes and Rhizobium leguminosarum increased root colonization
with VA-Mycorrhizae more than inoculation with VA-Mycorrhizae alone.
14- Dual inoculation with VA-Mycorrhizae and R. leguminosarum in the
presence of F. solani or R. solani increased the root colonization with
VA-Mycorrhizae and R. leguminosarum or F. solani or R. solani only.
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15- Fungicides increased the percentage of healthy survival plants and
reduced the percentage of root -rot disease especially Benlate 50 (at 1glkg
seed).
16- Fungicide (Benlate 50) reduced the plant height and root length,
whereas Mancoper was less affective on plant growth.
17- Seed dressing with fungicides and inoculation with VA-Mycorrhizae
reduced the root length and plant height compared with inoculation with
VA-Mycorrhizae alone.
18- Seed dressing with Benlate 50 and Mancoper decreased root
colonization with VA-Mycorrhizae for the two cultivars and also in
presence the pathogenic fungi (F. solani and R. solaniy. Percentage of
healthy survival plant increased in both VA-Mycorrhizae inoculation and
phosphate fertilization treatments compared with plants infected with F.
solani or R. solani in the two types of soil and for the two faba bean
cultivars, whereas) the percentage of root-rot infection was decreased in
this respect, the effect of G. macrocarpum resemble to G. australe.
19- VA-Mycorrhizal plants without phosphate had a high level of plant
height) root length and number of leaves more than non-Mycorrhizal
plants.
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20- Infection with F. solani or R. solani reduced plant height, root length,
number of leaves, root and shoot dry matter especially in case of absence
of phosphate, whereas VA-Myconhizal treatments increased them.
21- Soil inoculation with VA-Mycorrhizae (G. macrocarpum or G.
australe) without adding rock or super phosphate fertilizers increased faba
bean root colonization with VA-Mycorrhizal fungi compared with those
uninoculated ’with VA-Mycorrhizae. On the other hand, fertilization with
rock phosphate and inoculation with VA-Mycorrhizal fungi more than
super phosphate.