الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Eggplant plants (Solanum melongena L.) are vital important vegetable crop all over the world. It is one of the top ten vegetables grown in the world. Nowadays it is widely grown in different seasons throughout the year in the open field as well as in greenhouses. It contains 92.7% water, 1.4% protein vitamin A in small quantities.
Eggplant plants are known to be extremely susceptible to root-knot nematode infection.
Nematodes are considered one of limiting factors affecting vegetable production all over the world, causing severe damage that leads to yield losses. Plant-parasitic nematodes are estimated to cause global annual losses of more than US $100 billion. Nematode damage in crops is non-specific and causes a range of symptoms from mild to severe. Root-knot nematodes (Meloidogyne spp.) are an important group of plant parasitic nematodes that have worldwide distributions, wide host range, short generation times, high reproductive rates and endo-parasitic nature that make the control difficult. The four Meloidogyne spp. (M. incognita,
M. javanica, M. arenaria and M. hapla) are the major obligate parasites on many crops worldwide especially vegetables.
Results obtained from this present investigation can be summarized as follows:
1- In this study four liquid bacterial strains i.e., Pseudomonas fluorescens, Bacillus megaterium, Paenibacillus polymexa and Azospirillum brasilense as well as Trichoderma harzianum as a fungal bio agent were used at different incubation periods i.e., 24, 48,
72 and 168 hrs. to study their influnces on egg hatching and juvenile’s mortality of Meloidogyne spp. under laboratory condition.
The results showed that B. megaterium recorded the highest inhibition percentage of egg hatching and increased juvenile mortality, followed by T. harzianum while the least effective obtained with P. polymexa compared to the control.
2- Six eggplant cultivars i.e., SNO-8-1, 108-3-1, BPCL-1, SCR-2, CLA- 11-2 and SWD-13-1 were evaluated for their susceptibility to Meloidogyne spp. under greenhouse condition. Results revealed that the cultivar (108-3-1) was the most susceptible one with the highest number of galls, egg masses, females/root system and No. of J2/250 g soil while BPCL-1 cultivar was considered the most tolerant cultivar tested.
3- Results revealed that also the cultivar (BPCL-1) was the best one in all plant growth parameters i.e., stem and root length, fresh shoot and root weights, whereas the lowest parameters were achieved with the (108-3-1) cultivar.
4- Results revealed that the most susceptible cultivar (108-3-1) appeared high membrane leakage and low values in chemical constituents i.e., antioxidant enzyme activities peroxidase and polyphenoloxidase, whereas the cultivar (BPCL-1) appeared low membrane leakage and high values in antioxidant enzyme activities.
5- Results of HPLC analysis to study the differences between tolerant and susceptible eggplant cultivars to Meloidogyne spp. in aspect to accumulation of total phenol with root oxidates showed that the highest accumulation of total phenol compounds is detected with (BPCL-1) cultivar, whereas the lowest concentrations recorded in (108-3-1) cultivar.
6- The genetic variation among the six eggplant cultivars was studied by
using 10 primers for the SSR region, and the results indicated the presence of genetic diversity among the tested cultivars, especially within EEMS15 and EEMS16 primers.
7- Adding different bioagents (Bacillus megaterium, Pseudomonas fluorescens, Azospirillum brasilense, Paenibacillus polymexa and Trichoderma harzianum) at three different application times (one week before, at the same time and one week after nematode inoculation), as well as bioproduct (nemaless) compared with chemical control (fenamiphos) against root-knot nematodes, Meloidogyne spp., under greenhouse conditions. Fenamiphos showed the highest reduction in numbers of galls, egg masses, females/root system, and numbers of J2/250 g soil, and among all treatment within biocontrol agent B. megaterium showed the highest reduction of nematodes parameters when inoculated one week before nematode inoculation and the lowest one is P. polymexa one week after nematode inoculation compared to plants treated with nematode alone.
8- Adding different bioagents (Bacillus megaterium, Pseudomonas fluorescens, Azospirillum brasilense, Paenibacillus polymexa and Trichoderma harzianum) at three different application times (one week before, at the same time and one week after nematode inoculation), as well as bioproduct (nemaless) compared with chemical control (fenamiphos) against root-knot nematodes, Meloidogyne spp. increased plant growth parameters. The highest efficacy in stem and root lengths, fresh shoot and root weights is recorded with eggplant plants treated with fenamiphos, among all treatments within biocontrol agent B. megaterium one week before nematode inoculation compared to plants treated with nematode
alone.
9- Fenamiphos is the most effective in increasing the activity of antioxidant enzymes i.e., peroxidase and polyphenoloxidase, followed by B. megaterium before nematode inoculation. In contrarily the lowest effect was recorded with P. polymexa after nematode inoculation compared to plants treated with nematode alone.
10- Fenamiphos gave a higher reduction of membrane leakage.
Moreover, adding Bacillus megaterium before nematode inoculation gives a higher reduction of Ml compared with other treatments.
11- All the tested colors of polyethylene sheets i.e., (transparent, Black, Blue and Red) were effective in reducing the number of nematode galling index, No. of galls, egg masses, females/root system, reproduction factor and No. of J2 / soil. The transparent color sheet was the best one in reducing the nematode parameters, while the lowest value was recorded with the black color sheet.
12- All the tested colors of polyethylene sheets were effective in increasing plant growth parameters and the activity of antioxidant enzymes i.e., peroxidase and polyphenoloxidase. The best one was transparent color sheet, while the lowest value was recorded with the black color sheet.
13- The highest reduction in membrane leakage was obtained with transparent sheets, whereas the lowest one was recorded with black sheets compared with non-covered plants.
14- Covering pots with transparent color sheets increased soil temperature compared with non-covered pots.
15- The best combination of integrated biological and physical and
chemical methods was used to control Meloidogyne spp. by using transparent sheets as (physical method) + Bacillus megaterium applied before nematode inoculum as (biological methods) + fenamiphos as (chemical methods) along with tolerant eggplant variety reduced nematode parameters i.e., the number of galls, egg masses, females/root system and J2/250 g soil and reproduction factor in eggplant plants under greenhouse conditions.
16- Integration using transparent sheets as (physical method) + Bacillus megaterium applied before nematode inoculum as (biological methods) + fenamiphos as (chemical methods) along with tolerant eggplant variety was more effective in increasing plant growth parameters i.e., stem and root lengths, fresh shoot and root weights in eggplant plants under greenhouse condition.
17- Integration using transparent sheets as (physical method) + B. megaterium applied before nematode inoculum as (biological methods) + fenamiphos as (chemical methods) along with tolerant eggplant variety was more effective in increasing the activity of antioxidant enzymes i.e., peroxidase and polyphenoloxidase and recorded the highest reduction of membrane leakage.