الفهرس 
ACKNOWLEDGEMENT
Susceptibility of certain pomegranate cultivars to root-knot nematodesOnly 14 pages are availabe for public view
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Abstract
The present work was conducted to study the following main points: Survey studies on root-knot nematodes associated with pomegranate orchards of certain areas of Assiut Governorate, under field conditions. Identification of root-knot nematodes by perineal patterns and species specific markers (SCAR)
3. Host reaction of certain pomegranate cultivars; H116, Manfalouty, Assiuty and Wonderful to infection by M. javanica under greenhouse conditions.
4. Isolation and identification of some bioagent, that effects on M. javanica under laboratory and greenhouse conditions.
5. Effect of certain plant extracts on M. javanica under laboratory and greenhouse conditions. Effects of certain nanoparticles on M. javanica under laboratory and greenhouse conditions. Results of our study can be summarized in the following: 1- A total of 500 soil and root samples were collected from five counties; Sahel-Selim, El-Badary, Manfalout, Sedfa and El- Fath cultivated with Manalouty cultivar. Results showed that, the root-knot nematode is found with different population density in all the collected samples.
2- Perineral patterns and the PCR based marker (SCAR) observed that, Meloidogyne javanica is dominant in all pomegranate orchards.
3- Studying the susceptibility of certain pomegranate cultivars to the M. javanica, showed that, the pomegranate cultivars differed in their susceptibility to the M. javanica. Where, H116 and Wonderful cultivars were resistant while, Manfalouty cultivar was susceptible. Twenty nine isolates of fungi, 12 isolates of bacteria, 4 isolates of yeast and one actinomycetes isolate were isolated from rhizosphere of pomegranate healthy plant.
5- In vitroassay of fungal culture filtrate, yeast, bacteria and actinomycetes against percentage of J2 mortality were done.
- Fungal culture filtrate of isolates no. 3, 10 and 2 gave the highest percentage of J2 mortality.
- Bacteria isolates no. (10, 8, 9 and 15), yeast no. (16) and actinomyces no. (11) showed high mortality of J2 percentage.
- In this experiment, the J2 mortality percentage affected with exposure period time to fungal culture filtrate or antagonistic isolates.
6- The best antagonistic isolates and fungal culture filtrate taken from it’s against M. javanica were identified. Fungal isolate (no. 3) identified as Fusarium verticilliodes, bacteria isolates (no. 10 and 12) were Xenorhabdus beddingii and Pantoea agglomerans, yeast isolate (no. 16) was Pichia guilliermondii and actinomycetes isolate (no. 11) was Streptomyces halstedii.
7- Plant extracts at different concentration (25, 50, 75 and 100%) were tested to controll M. javanica in vitro. All treatments were significantly decrease J2 viability and garlic clove extract was the highest percentage of mortality followed by neem, while caster bean was the lowest. There was a significant difference between concentrations of the extracts and percentage of mortality the best concentration of each extract was at 100%. Moreover, the exposure period affected on percent of mortality. The highest J2 mortality percentage was after 48 hrs.
8- Effect of iron and silver nanoparticles against M. javanica at different concentration (1, 5, 10, 15 and 20 ppm) was tested in vitro. The best concentration of each nanoparticle gave high percentage of J2 mortality was at 20 ppm. There was no significant between iron and silver nanoparticles against J2 mortality percent.
9- Under greenhouse conditions, F. verticilliodes, P. agglomerans, X. beddingii, P. guilliermondii, S. halstidii, garlic extract, iron nanoparticles and nematex were significantly affected on M. javanica populations.
10- P. agglomerans, iron nanoparticles and Nemateax gave a significant increase in redusing the number of M. javanica J2. Iron nanoparticles was decreased the number of root galls followed by X. beddingii and P. agglomerans under greenhouse conditions. Iron nanoparticles, X. beddingii, P. agglomerans and Nemateax were decreased the number of egg masses.