الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Tomato is one of the most important vegetable crops in agriculture due to its nutritional value. Studies have proven that tomatoes have the ability to fight some diseases, such as fighting cancer, controlling diabetes, promoting heart health, preventing osteoporosis...etc.. It also contains carotenoids and lycopene that help to lower cholesterol, improve immune function, reduce blood clots, and provide the body with vitamin C, which is important for healing wounds and building strong bones and teeth.
Tomatoes are attacked by many insect and animal pests. Nematodes are one of the most important pests that cause great losses if they are not controlled. Many species of parasitic nematodes infected tomato plants have been recorded in Egypt, the most common of which are:
Meliodogyne spp., Pratylenchus spp... Criconemella spp., Xiphinema spp., Helicotylenchus spp.
Meliodogyne spp is considered the most dangerous species that causes severe damage to the productivity of the tomato crop quantitatively and qualitatively. All previous research studies recorded a negative correlation between the number and the density of root-knot nematodes and the productivity of tomato crop.
Controlling nematodes are very difficult when compared to the control of other pests due to the nature of the living and behavior of nematodes in the soil, and their attack on the roots. Usually, nematode controlling programs depend on chemical control using traditional nematicides, which follow the Carbamate and organophosphorous groups, by treating the soil with traditional methods, or by smoking. Controlling nematodes with traditional pesticides has led to the emergence of resistant species to pesticides. Pollution of the environment especially groundwater and the bad side effects of these pesticides on human health and non-target organisms.
Many recent research studies have tended to search for alternatives to traditional nematicides that are safe to use on ecosystems, on human health and on non-target organisms.
The most important alternative method is the use of biological pesticides (natural origin of bacterial, fungal, or vegetable origin) which have been successful in combating many types of nematodes that are parasitic on plants. Organic acids and beneficial fungi, which is characterized by a non-toxic physical action mechanism to reduce the ability of nematodes to penetrate the roots of treated plants is considered also as alternative method.
Aim of the study:
1-Identify the most important nematodes that infect different varieties of
tomatoes under field conditions.
2-Study of the susceptibility of some commercial tomato varieties to the
genus root knot nematodes.
3- Evaluating the effectiveness of some commercial biocides (of bacterial,
fungal, or vegetable origin) as successful nematicides for root-knot
nematodes most present in the soil, and comparing their effect a
chemical pesticide.
4- Evaluation of the effectiveness of some safe materials in reducing the
numbers of root knot nematodes, as well as their effect on the vegetative
and root characteristics of tomatoes.
5- Evaluation of mixtures of biocides, chemicals and safe materials and
studying their efficiency in reducing root-knot nematodes.
This study was carried out at the research station attached to the Faculty of Agriculture, Menoufia University - Shebin El-Kom, Menoufia Governorate, and also at the Nematode Research Laboratory, Department of Economic Insects and Agricultural Animals, Faculty of Agriculture, Menoufia University.
Results:
Part One: (field study to find out the most important nematodes that attack the commonly used tomato varieties in Egypt).
A field experiment was conducted in the farm of the Faculty of Agriculture, Menoufia University. Four varieties of tomatoes which traded in the Egyptian agricultural market: (super sweet - super estrain B - zaina RS695 vacolta) were cultivated to know the most important genera of nematodes that infect these varieties.
1-Super sweet.
There were five genera of parasitic nematodes that attacked this species in different proportions (Meloidogyne spp., Pratylenchus spp., Criconemella spp., Xiphinema pp., Helicotylenchuss spp).
Meloidogyne spp recorded the highest presence compared to other genera with an average (69%) followed by the genus Pratylenchus spp (20.4%) while the genus Xiphinema pp had lowest percentage (0.1%).
2- Super strain B.
There were five genera of parasitic nematodes that attack this species in different proportions, and they are: Meloidogyne spp., Pratylenchus spp., Criconemella spp., Xiphinema pp., Helicotylenchuss spp.
The genus Meloidogyne spp recorded the highest presence compared to the other genera with an average of (67.1%), followed by the genus Pratylenchus spp with a rate of (17.4%), while the genus Xiphinema pp. The lowest percentage of presence with an average reached (0.1%).
3- Zaina RS695.
The highest incidence was for Meloidogyne spp with (60.0%), followed by Pratylenchus spp with (21.7%), and the lowest was for Helicotylenchus spp with (5.8%).
4- Vacolta38.
The highest percentage was for Meloidogyne spp with a prevalence of (60.8%), followed by Pratylenchus spp with (25.1%) and the lowest was for Xiphinema americanum (0.2%).
It is clear from the previous experience that the Meloidogyne genus represents the highest incidence and infection rate compared to other nematodes, and accordingly an experiment was conducted to assess the sensitivity of tomato varieties to the Meloidogyne genus.
Part Two: (Assessment of the sensitivity of some common tomato cultivars grown in Egypt to the genus Root-knot nematodes).
An experiment was conducted in pots under field conditions, and the infection occurred at three different times.
1- The time of planting seedlings
2- One week after planting
3- Two weeks after planting.
The most important results obtained were as follows
1- super sweet:
1- Juvenile count.
The highest numbers of root-knot nematodes were recorded when the infection was carried out at the time of planting with an average of (1892.4), followed by two weeks after infection with an average of (1749.0), and the lowest number of juvenile after planting was one week with an average of (1771.6).
2- vegetative and root traits.
It recorded the vegetative and root characteristics of plants infected with root knot nematode that infects super sweet variety, and the highest plant height was after treatment two weeks (53 cm) followed by a week after treatment (51 cm), and the lowest plant height during cultivation was (49.5 cm). Then the weight of the vegetative mass was recorded, and it was the highest weight after the treatment in a week (70 g), followed by two weeks after treatment (68 g), and the lowest weight was during the cultivation procedure (67 g). As for the weight of the roots, the highest weight of the roots was recorded after treatment two weeks (21 g) and after planting a week (18 g), and the lowest weight of the roots during the experiment was (16.5 g). Then the root gall index was recorded, and it was the highest percentage of root knots during planting and it was (4) and the root gall percentage is equal after the treatment one week and two weeks by (3).
2- Super estrain B.
1- Juvenile count.
where the highest numbers of root-knot nematodes were recorded when the infection was carried out at the time of planting with an average of (2555.3), followed by two weeks after infection with an average of (2226.6), and the lowest number of larvae after planting was one week with an average of (2064.0).
2- Vegetative and root traits.
It recorded the vegetative and root characteristics of plants infected with root knot nematode that infects super estrain B class. The highest plant height after treatment was two weeks (45.5 cm), followed by a week after treatment (43.5 cm), and the lowest plant height during the cultivation procedure was (39.0 cm). Then the weight of the vegetative mass was recorded, and it was the highest weight after treatment in two weeks (63.5 g), followed by a week after treatment (62.0 g), and the lowest weight was during the cultivation procedure (59 g). As for the weight of the roots, the highest weight of the roots was recorded after treatment two weeks (12.0 g) and a week after planting (10.0 g), and the lowest weight of the roots during the experiment was (8.0 g). Then the root gall index was recorded, and it was the highest percentage of root nodules equal during cultivation and one week after the treatment and it was (5.0), and then it was two weeks after planting with a percentage of (4.0).
3- Zaina RS695:
1- Juvenile count.
where the highest numbers of root-knot nematodes were recorded when the infection was carried out at the time of planting with an average of (1693.0), followed by an average of (0.1642) one week after infection, and the lowest number of larvae after planting was two weeks with an average of (1633.6).
2- vegetative and root traits,
It recorded the vegetative and root characteristics of plants infected with the root knot nematode that infects Zaina RS695. The highest plant height after treatment two weeks (58.5 cm) followed during the experiment was (55 cm), and the lowest plant height was (45 cm) a week after treatment. Then the weight of the vegetative mass was recorded, and it was the highest weight after treatment in a week (78 g), followed by two weeks after treatment (77 g), and the lowest weight was during the cultivation procedure (74 g). As for the weight of the roots, the highest weight of the roots was recorded after the treatment two weeks (22.5 g) and the second during the experiment was (20.5 g), and the lowest weight after the treatment was (17.0 g). Then the root gall index was recorded, and it was the highest percentage of root nodules two weeks after conducting the treatment, and it was (3).
4- Vacolta38:
1- Juvenile count
where the highest numbers of root knot nematodes were recorded two weeks after infection with an average of (1641.6), followed by during infection with an average of (1567.3), and the lowest number of larvae after planting was in a week with an average of (1527.0).
2-vegetative and root traits.
It recorded the vegetative and root characteristics of plants infected with the root knot nematode that infected Vacolta38 variety. The highest plant height after treatment was two weeks (59 cm), followed by a week after treatment (56 cm), and the lowest plant height during cultivation was (55.5 cm). Then the weight of the vegetative mass was recorded, and the highest weight was after treatment in two weeks (75.5 g), followed by a week after treatment (72 g), and the lowest weight was during the cultivation procedure (68 g). As for the weight of the roots, the highest weight of the roots was recorded after two weeks of treatment (19 g) and followed by it during the procedure experiment (17 g) and the lowest weight of the roots after planting one week (16 g). Then the root gall index was recorded, and it was the highest percentage of root knots after planting a week (3), and the root gall percentage was equal during the experiment and two weeks after the treatment.
And it becomes clear at the end of the experiment that the super estrain B class is the most sensitive class and accordingly control experiments were conducted.
Part three: (Evaluation of the effectiveness of some commercial preparations of biocides as successful nematicides against the genus of root-knot nematodes most present in the soil and comparing their effect with the effect of a chemical pesticide on root-knot nematodes).
As Vydate, Nemafree, Bio-zeid, and Nemastop were used. Whereas, the Vydate caused the highest reduction percentage in root-knot nematode juvenile of 88.2% and led to an increase in plant height by 49.1% and an increase in the shoot weight to 25.04%, an increase in the weight of roots to 112.9% and a decrease root gall index by 80% compared to the control.
Followed by the pesticide of Bio-zeid origin, which caused a reduction percentage of 77.7%, which led to an increase in the length of the plant to 52.9% and an increase shoot weight to 23.1% and an increase in the weight of the roots to 107.8 and a decrease root gall index by 80% compared to the control.
Nemafree is an exterminator of bacterial origin, which causes a death rate of 71.4, which leads to an increase in plant height by 36.8%, an increase shoot weight to 17.7%, an increase in the weight of roots to 89.6%, and a decrease root gall index by 60%, while the lowest percentage was for the pesticide of plant origin
Nemastop caused a death rate of 70.2%, which led to an increase in plant height by 16.6%, an increase shoot weight by 13.9%, an increase in the weight of the roots by 59.7%, and a decrease in root gall index by 40%.
Fourth Part: (Evaluation of the effectiveness of some safe materials in reducing the population density of root-knot nematodes, as well as their effect on the vegetative and root characteristics of tomatoes).
where we used some safe materials, including mycorrhiza, humic acid, salicylic acid, and Novatrin foliar fertilization.
G. mosseae caused the highest death rate in root-knot nematode juvenile by 60.4%, which led to an increase in plant height by 63.7% and an increase in the shoot weight to 68.6% and an increase in the weight of roots to 18.5% and a decrease root gall index by 3% compared to the control.
Followed by Humic acid, which caused a death rate of 59.7%, which led to an increase in plant height by 68.8%, an increase shoot weight to 74.1%, an increase in the weight of roots to 17.2%, and a decrease root gall index by 2.0%,
while the lowest percentage was for Salicylic acid, which caused a death rate by 68.4 % led to an increase in plant height by 73.9%, an increase in the shoot weight by 16.8%, and a decrease root gall index to 3.0%.
Part Five: (Evaluation of mixtures of biocides, chemicals and safe materials and a study of their efficiency in reducing root-knot nematodes and improving vegetative and root characteristics of tomatoes).
The triple treatment (Humic acid + G. mosseae +Vydate (half dose)) gave the highest mortality rate in the second stage juvenile of root-knot nematodes with a percentage of (90.0%), followed by the triple treatment (Humic acid + G. mosseae + Bio-zeid (half dose)) which caused the death rate of root-knot nematodes J2 by (88.0%).
As for the two treatments that had the highest effect on root-knot nematodes J2, double treatment (G. mosseae + Vydate (half dose)), which gave a death rate of root-knot nematodes J2 reaching (81.6%), followed by the dual treatment (G. mosseae + Bio-zeid (half dose)), which gave a death rate of (79.8%), while the lowest bilateral treatment was (Humic acid + G. mosseae), which gave a death rate of (63.8%), compared to the chemical nematicide (Vydate (full dose)), which gave a death rate by (87.1%).
Triple treatment (Humic acid + G. mosseae +Vydate (half dose)) improved the vegetative and root characteristics of tomato plants, as it led to an increase in plant height, shoot weight and root weight in percentages (+50.6% & +28.1% & 143.2%) respectively compared to the control . It also led to a decrease in root gall index by (-80.0%) compared to the control.
As for the triple treatment (Humic acid + G. mosseae + Bio-zeid (half dose)), it improved the vegetative and root characteristics of tomato plants, as it led to an increase in plant height, shoot weight and root weight in percentages (+53.0% & +29.0% & 148.1%). respectively compared to the control. It also led to a decrease root gall index by (-80.0%) compared to the control.
Dual treatment (G. mosseae + Vydate (half dose)) improved the vegetative and root characteristics of tomato plants, as it led to an increase in plant height, shoot weight and root weight in percentages (+45.9% & +20.7% & 133.3%), respectively, compared to the control. It also led to a decrease root gall index by (-60.0%) compared to the control.
Conclusion:
1- Meloidogyne is one of the most numerous and dangerous parasitic nematodes that attack tomato plants.
2- Super estrain B cultivar is considered one of the most sensitive tomato cultivars to Meloidogyne javanica compared to the rest of the studied cultivars.
3- The chemical nematicide Vydate 24% L is more effective on root-knot nematodes that infect tomatoes, followed by the bio-zeid, then Nemafree, and finally Nemastop.
4- The study concluded that there are safe and effective alternatives against root-knot nematodes that give better results than the effect of the chemical pesticide, as the triple treatment (Humic acid + G. mosseae + Bio-zeid (half dose)) gave a higher death rate than the chemical nematicide, as well as the use of treatments safe with half the dose of the chemical nematicide, it had a greater effect than the chemical nematicide Vydate on root-knot nematodes.
Therefore, this study recommends the use of environmentally safe methods for humans, animals and plants, as well as effective on root-knot nematodes, as an alternative to the excessive use of chemical nematicide, which cause significant damage to the public health of humans and animals.