الفهرس 
INTRODUCTION
The causal pathogen of tomato wilt diseaseOnly 14 pages are availabe for public view
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Abstract
SUMMARY
Tomato (Lycopersicon esculenVtum Mill.) is one of the most popular and important commercial vegetable crops grown throughout the world. Fusarium wilt is considered to be one of the most deleterious diseases which attack tomato seedlings eithe) Isolation of the causal pathogens from different varieties and locations in Assiut governorates (II) Identification the causal pathogens was r in the nurseries or in the field after transplanting. This disease cause great losses is spread in many parts of the world. Many Fusarium species causes wilt disease such as F. oxysporum f. sp. lycopersici, F. solani, F. nygamai, F. circinatum and F. proliferatum. The present study aimed to (I carried out by using morphological characteristics then confirmed by Assiut University Mycological center (AUMC) (III) Genetic diversity among some Fusarium species and the reaction of certain cultivars by genetic differenation between it (IV) Control the disease by humic acid , L-methionine and phosphoric acid in vitro and a soil application and their effect on protein profiling and activity of defense enzymes. (V) Using two biocides such as Bio Zeid and Bio Arc and their effect on protein profiling and activity of defense enzymes. (VI) Using some salts for controlling the disease.
Results of the study can be summarized as follows:
1- Fourteen isolates of Fusarium spp. (9 isolates of F. oxysporum f. sp. lycopersici, 2 isolates ofF. solani and one isolate from each F. nygamai, F. circinatum and F. proliferatum) were isolated from infected roots of tomato plants which collected from various locations in Assiut Governorates showing wilt symptoms.
2- The tested isolates of Fusarium spp. were able to infect Super Jakal and 745 tomato cultivars and produced typical symptoms wilt disease. The highest percentage of disease severity was caused by F. oxysporum f. sp. lycopersici isolate No. 1 and 4 on super Jakal cultivar (78.10%). Meanwhile, F. oxysporum f. sp. lycopersici isolate No. 5 and F. nygamai No. 8 caused the lowest percentage of infection on 745 cultivar (25). While other isolates gave a moderate percentages of infection.
3- Genetic diversity among some Fusarium species was studied by(a) Inter-simple sequence repeats (ISSR) (b) Sequence related amplified polymorphism (SRAP) and genetic similarity among them.
4- Molecular markers differentiating between Fusarium spp. based on diseases severity. Five DNA bands at molecular weights, 380 bp (ISSR-814), 401 bp (ISSR-844), 315 bp (SRAP-1), 144 bp (SRAP-2) and 564 bp (SRAP-3) were detected only in four F. oxysporum f. sp. lycopersici isolates No. (1, 2, 4 and 10) which had the highest number of DNA bands (101, 94, 97 and 97 respectively) these isolates gave the high mean percentage (51.94%) for diseases severity across the two tomato genotypes, while the other isolates gave the low mean percentage (34.65%) for diseases severity across the two tomato genotypes. These isolates had DNA band ranged in number from 76 bands for F. oxysporum f. sp. lycopersici isolate No. (9) to 91 bands for F. oxysporum f. sp. lycopersici isolate No. (7).
5- Reaction of four tomato cultivars (Super Jakal, 745, Super Strain-B and Super-Marmande) to infection with Fusarium wilt caused by F. oxysporum f. sp. lycopersici and F. solani was tested under greenhouse conditions and also genetic differenation between them was studied. The highest percentage of Fusarium wilt occurred in Super Strain-B followed by Super-Marmande, then Super Jakal. While745 cultivar showed the lowest percentage of Fusarium wilt disease.
5.1. Comparison of protein gel electrophoresis in the discrimination of eight Fusarium species isolates was carried out. The protein profile of different isolates showed eleven bands. Six bands at molecular weight 36.1, 34.5, 29.2, 23.4 and 20.1KD were common protein band in all isolates. Protein band at molecular weight 56.8KD was appeared only in all isolates of F. oxysporum f. sp. lycopersici but not appeared in the two isolates of F. solani. On the other hand protein band at molecular weight 38.4KD was presented in the two isolates of Fusarium solani but not appeared in all isolate of F. oxysporum f. sp. lycopersici. These two bands 56.8KD and 38.4KD could be used to differentiation between the two species. Two protein bands at molecular weight 49.3 and 18.2 KD were detected in four isolates of F. oxysporum f. sp. lycopersici No. (1, 2, 4 and 10). Protein band at molecular weight was found in two isolates of F. oxysporum f. sp. lycopersici No. (1 and10) only.
5.2.Protein analysis of four tomato genotypes Super Strain-B, Super Marmande, Super Jakal and Hybrid 745 was determined by electrophoretic protein patterns. The four healthy tomato genotypes exhibited different protein patterns. Eleven out of twenty protein bands were conserved in four tomato genotypes. The genotype Hybrid-745 had the highest number of protein bands (20 bands) followed by the genotype Super Jacal (19 bands) while the two genotypes Super Marmand and Super Strain-B had the lowest number of protein bands (15 bands) for each.
6- Studying the effect of some compounds (Phosphoric acid, humic acid and L-methionine) against Fusarium isolates in vitro and under greenhouse conditions showed:
6.1- In vitro, phosphoric acid gave thehighest effect of the linear growth of the pathogens followed by L-methionine and humic acid with all tested isolates of pathogens.
6.2- Under greenhouse conditions, soil amended with phosphoric acid, L-methionine and humic acid after sowing.Result show all testedcompounds were effective in reducing the disease severityof tomatowiltdisease. Phosphoric acid caused the highesteffect inreducing the disease severity percentageat both seasons followed by L-methionine. While, humic acid gavethe lowest effect on disease severity.
Treated tomato plants (Super strain B cv.) with these compounds showed differences in protein and isozymes banding patterns compared to untreated plants. In general, control plants exhibit 20 protein bands these common in all treatments except protein bands at molecular weight protein 11 which disappeared in all infected plants with F. oxysporum f. sp. lycopersici No. 1. Protein bands at molecular weight 47.2, 38.2, 16.3 and 15.6 KD appeared only in treated plants with these compounds. New esterase, peroxidase, chitinase and Superoxide Dismutase isozyme bands were detected in all treatments while not appear in the control. The results indicate that all tomato treated with these compounds, showing variability in number, relative mobility and density of esterase, chitinase, peroxidase and Super Oxide Dismutase isozymes compared with control plants. The SDS-PAGE protein profile of total soluble protein from infected plants treated with all treatments showed differences in band pattern when compared with control plant. These results revealed that all treatments were able to induce new protein banding patterns which increases resistance in tomato plants to Fusarium wilt disease, but treatment with L-methionine was the best because it induced three new protein bands.
7- Studying the effect of Bio Zeid and Bio Arc against Fusarium isolates under greenhouse conditions.Bio Zeid and Bio Arc were effectivein reducing the disease severity of tomatowiltdisease.Bio Arc was showed the more effective in reducing the disease severity of tomato wilt disease severity at both seasons.
Treated tomato plants (Super strain B cv.) showed differences in protein and isozymes banding patterns compared to untreated plants. Two new protein bands at molecular weight 47.2 and 16.3 KD were appeared in all infected plants treated with Bio-Zeid and Bio-Arc while, not appeared in control plant. This indicates that these treatments were able to induced new protein bands which increase resistance in tomato plants to Fusarium wilt infection. All treatments were able to induced new protein bands patterns which increasing resistance to Fusarium wilt, but treatment with Bio-Arc was the best because it induced the higher numbers of new protein bands. At the same time, new esterase band (EST-5a), peroxidase (PRX-4a), chitinase (Chit-5b) and Superoxide Dismutase isozyme (SOD-1a) bands were detected in all treatments while not appeared in the control.
8.1- In vitro, evaluated the effect of sodium citrate, sodium carbonateand potassium carbonate on linear growth of Fusariumisolates atdifferent concentrations (50, 100, 150 and 200 mM)onPDAmedium. All tested chemicals inhibitedthe lineargrowth of the pathogen isolates with different degree according tosubstance and concentrations. The highestreduction of the linear growth of the pathogen caused by sodium carbonate with all tested isolates of pathogen followed by potassium carbonate, while sodium citrate caused the lowest inhibition of pathogen growth.
8.2- Tomato seedlings were dipped in solution of sodium citrate, sodium carbonateand potassium carbonate at concentration 200mM for10 minutes before planting was effective in decreasing Fusarium wilt disease. Generally, all tested chemicals exhibited high control for Fusarium wilt disease. Data also indicate that sodium carbonate was the best in controlling the disease, followed by potassium carbonate, sodium citrate showed the lowest effect on the disease.