الفهرس 
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Abstract
Strawberry (Fragaria ananassa Duch) belongs to the family of
Rosaceae. In the last few years, it was considered as an important
vegetable crop in Egypt. It has been considered one of the most
important export crops in Egypt in 2014. Egypt ranked 4th globally in
exporting strawberry in terms of quantity and quality. Fresh strawberry
are grown in three main governorates of Egypt: Beheira, Qalioubia and
Ismailia. In 2016, the area of planted strawberry reached 9985 hectares,
according to FAO statistics in 2016.
Strawberry attacked by many diseases that cause great economic losses,
many of which may destroy the entire crop. Some diseases that affects
on the crown and causes rot such as fungal disease caused by fungus
Macrophomina phaseolina. It is one of the most important diseases
affecting the strawberry crop and causes economic losses for
strawberries in Egypt.
M. phaseolina is a common fungus in the soil that attacks strawberry
plants either in the nursery or in the production land and causes the
rotary mold disease, which in turn leads to the collapse of the plants and
their death, even if the plants do not collapse and die, productivity
decreases.
This study was carried out at the Plant Pathology laboratory at the
Modern Agriculture Company PICO in the Badr Center in Beheira
governorate and the plant diseases laboratory at the Faculty of
Agriculture in Shebin El Koum Monofia University under the
conditions of the greenhouse in the Modern Agriculture Company
PICO in Badr governorate of the governorate of Beheira during the
period from 2016 to 2018.
The work plan was designed to study the following points:
1- Survey of the disease in different locations in Beheira
Governorate.
2- Isolation, purification and Identification of the causal
organism.
3- Pathogenicity test of the isolated fungal isolates.
4- Biological control of charcoal rot on strawberry plants.
5- Chemical control of charcoal rot on strawberry plants.
Pathogenicity tests were conducted using all isolates of the fungus
causing the pure disease at the same time to using determine the
strongest isolates of the isolated fungal pathogen, as well as to know the
most sensitive strawberry cvs. to charcoal rot disease. A number of
laboratory studies were conducted on the isolates to differentiate
between them. Also, an evaluation test was conducted on the
commercial strawberry cultivars cultivated in Egypt using the strongest
isolates of the fungus causing the disease to determine the sensitivity of
the varieties to infection.
Methods of control to this disease have been followed under this study
belonging reduce environmental pollution and reduce the use of
pesticides. It attempts to control the disease using biocontrol agent that
have been isolated from the environment surrounding the infected
plants. These experiments were carried out under the conditions of the
greenhouse.
Attempts were also made to control the disease using some recomented
pesticides the Egypt and compare them with biological control.
The obtained results can be summarized as follows:
1-The disease was screened 69 of the most strawberry growing areas,
namely the Beheira governorate (Badr Center and Kom Hamada
center) the disease was found in 37 of these areas according to the
morphological disease and the distribution of the disease in the crown
area.
2-Seven isolates of M. phaseolina were selected from infected plant
samples showing symptoms of the disease obtained from seven
different regions.
3-Eight isolates of the Trichoderma spp. were isolated from soil
samples and from the rhizosphere of strawberry plants isolated from
the same sampling areas. The isolates were three isolates of T. viride,
three isolates of T. hamatum, on isolate of T. harzianum and one
isolate of T. koningii.
4-Pathogenicity tests of seven isolates of M .phaseolina was
determined using Festival of c.v strawberry, which is the most
sensitive commercial categories. The tested isolates showed varying
capacities to infect the plants.
5-Pathogenicity tests reveal of that there were significant differences
between the isolates used in the infection in terms of its ability to
cause the disease. The strongest isolates was No. (3), which isolated
from the area of Abdelmajid Morsy at Badr location from (Festival)
cv. This isolate was selected to complete the study (Varietal
sensitivity, chemical control, and biological control).
6-In the tests of the susceptibility of four commercial varieties i.e.,
(Festival, Winter Star, Fortuna, 029) which the most grown in
Beheira governorate, 029 cv. showed the lowest degree of
susceptibility to the disease, while Festival was the most susceptible
cv. under greenhouse conditions.
7-When testing the effect of fungicides under the conditions of the
greenhouse in the control of charcoal rot on strawberries, Rhizolex-T
and Sendo were more effective, where the proportion of survival
plants treated with Rhizolex-T 80%, and Sendo 60%, while the
pesticide Ridomil Gold Plus was the least effective one, since where
the proportion of survival plants were 10%.
8-When testing the effect of fungicides in inhibiting the growth of the
fungus M. phaseolina under laboratory conditions and in petri dishes,
the pesticides showed a decrease in the growth of M. phaseolina in
varying degrees at the highest concentration of 200 ppm. The highest
percentage of inhibition of pathogen growth was obtained by the
pesticide Rhizolex -T gave a 96.67% inhibition followed by Sendo,
which gave 95.56% inhibition. Ridomil Gold Plus was the least
pesticide, giving an inhibition ratio of 43.06%.
9-Under laboratory conditions and in petri dishes, biocontrol agent
showed a positive effect against four isolates of M. phaseolina,
reduced the growth of pathogenic fungal isolates. The highest
inhibitory rate was obtained in the growth of pathogen isolates (1) by
T. hamatum (1), while T. harzianum was the least inhibitory rate
against this isolate from the pathogen. In Isolate, (3) of the pathogen
also T. hamatum (1) gave the highest inhibitory factor while T.
harzianum was the least inhibitory rate against this isolate of the
pathogen. In isolate, 6 of the pathogen T. hamatum (3) was the highest
inhibitory factor while T. harzianum was the least inhibitory rate
against this isolate of the pathogen. Isolation of the pathogen (7) was
holily inhibited by T. viride (1) while T. harzianum gave the least
inhibition rate against this isolate from the pathogen.
10- Results of biological control under greenhouse conditions,
showed that biocontrol agent gave positive results against four
isolates of the fungus M. phaseolina, T. hamatum (1,2) showed the
highest percentage of survival plants against isolation (1) from the
pathogen. T. harzianum showed the lowest percentage of survival
plants. When isolate (3) from the pathogen was used T. hamatum (1)
and T. koningii isolates showed the highest survival plants, whereas
T. harzianum isolates recorded the lowest percentage of survival
plants. T. hamatum (1) and T. koningii (1) recorded the highest
percentage of survival plants against isolate No 6 of M. phaseolina,
while T. harzianum had the lowest percentage in this respect. T.
hamatum(2) was used as abioagent to word isolation .7 of the latest of
pathogen the highest percentage survival plants, while the T.
harzianum had the lowest percentage of survival plants.