الفهرس 
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Abstract
In Egypt, tomato is important for national income. Tomato infects with many phytopathogenic diseases such as fungi, virus, nematode and bacteria. Fusarium wilt disease caused by F. oxysporum f. sp. lycopersici (FOL) causes a serious problem in tomato production. The main objectives of this research are to collecting samples of wilted tomato plants and isolation, purification, identification, and verification of FOL isolates. Testing the pathogenicity of FOL isolates and studying the varietal responses of different tomato cultivars to infection with Fusarium wilt. Studying nucleotide sequence analysis of the obtained FOL isolates and determination of their similarity with the isolates submitted to the Gene Bank. Culturing, purification and verification of Trichoderma, Ulicladium and Verticillum isolates. Testing the effect of bio-control agents on the radial growth of FOL (In vitro). Determination the efficacy of selected bio-agents on the induction of SIR in both resistant and susceptible tomato cultivars (In vivo). Determination the activity of enzymes like Peroxidase, Polyphenol oxidase and β-1,3 glucanase using RT-PCR for detection of gene expression.
The main results were:
6.1. Morphological culture differences of pathogen isolates
1- For morphological culture differences of FOL the highest colony diameter (80 mm) was of isolate FOL 1 after ten days of incubation at 27 ± 2 °C temperature However, the lowest colony diameter (45 mm) was of FOL 6 isolate.
2- There were differences in cultural characteristics of ten isolates, all isolates produced slight to profuse fluffy in mycelium Colony characters and dull yellow, light pink, purple, dark pink, pink white with yellowish pigmentation, as isolates FOL 1 & FOL 5 produced profuse fluffy mycelium with light pink and purple pigmentation. While the isolate FOL 3 & FOL 4 produced moderate fluffy mycelium with pink and white pigmentation followed by isolate FOL 2. However, FOL 6, FOL 7 and FOL 8 produced thin flat mycelium with yellowish white and light pink pigmentation. Finally, both of isolate FOL 9 & FOL 10 produced profuse fluffy mycelium with pink & white and dark pink pigmentation.
6.2. RAPD-PCR and ITS markers for variability of FOL isolates
3- Four different RAPD primers and ten isolates of FOL were used in current studies to identify the differentiation among isolates. The total amplification fragments were detected for the tested isolates in a total 300 fragments and separated among isolates as follow: (FOL 1) 39, (FOL 2) 32, (FOL 3) 29, (FOL 4) 30 (FOL 5) 31, (FOL 6) 24, (FOL 7) 32, (FOL 8) 27, (FOL 9) 26 and (FOL 10) 30 bands. The highest amplification fragments were recorded in isolate FOL 1. While, the isolate FOL 6 showed the lowest fragment size.
4- The genetic similarity among the ten FOL isolates was detected, a high similarity was observed among the ten FOL isolates (FOL 3 and FOL 4), (FOL 9 and FOL 10). However, low similarity was observed between (FOL 3 & FOL 9), (FOL 3 &FOL 10), (FOL 4& FOL 9) & (FOL 4 & FOL 10) in respective manner.
5- The phylogenetic tree constructed based on the obtained results by the RAPD revealed that, ten FOL isolates were grouped into two main clusters (Cluster I and Cluster II). Cluster I was split into two sub-clusters: Sub-cluster1 contains two isolates FOL 4 and FOL 3. Sub- cluster 2 contains one isolate FOL 2. In case of Cluster II was divided into two sub-clusters: Sub-cluster 1 contains two isolates, FOL 10 and FOL 9. While sub-cluster 2 was split into three groups: group 1 contains one isolate FOL8, group 2 included two isolates, FOL 7 and FOL 6, whereas group 3 included two isolates, FOL 5 and FOL1.
6- The results for specific primer ITS (ITS1- ITS4) showed that FOL isolates FOL 1, FOL 2, FOL 3, FOL 8 and FOL 10 were identified as F. oxysporum f. sp. lycopersici and produced the same fragments at 500 bp. Then, the DNA sequences were submitted to NCBI databases.