A survey of plant parasitic nematodes associated with the rhizosphere of cotton cvs. Giza 86 and 45 grown in fourteen locations of Dakahlia and Damaita governorates was carriedout during the cotton growing seasons of 2005 and 2006, , in addition, a pot experiment was conducted to determine host suitability of three cotton cultivars i.e. Giza 86, 89 and Giza 45 to Meloidogyne incognita infection under greenhouse condition at 30±5ºC . Twelve nematode genera were recorded in cotton fields surveyed in Dakahlia governorate, whereas nine nematode genera only for those of Damaita governorate. Based on their frequency of occurrence these genera can be arranged in descending order as follows: Tylenchus (46.3%), Tylenchorhynchus (39.7%), Xiphinema(23.9%), Meloidogyne (19.0%), Rotylenchus (10.7), Hirschmanniella (9.1%), Trichodorus (8.25%) ,Hoplolaimus(7.49%), Rotylenchulus (7.4%), Helicotylenchus (4.9%) , Psilenchus (1.6%) and Pratylenchus (0.82%),for Dakahlia , whereas Meloidogyne (68.0%) , Tylenchus (64.0%), Tylenchorhynchus (60.0%), Heterodera (38.0%), Dorylaimus (14.0%), Hirschmanniella (10.0%), Helicotylenchus (8.0%) ,Aphelenchus ( 8.0%0) and Psilenchus (2.0%) for Damiata. cotton cv. Giza 86 appeared to encounter the highest number of nematode genera (10) while Giza 45 gained (5) only. Screening of the selected cotton cultivars against M. incognita infection revealed that plant growth parameters tested were obviously affected to a certain extent, where cotton cv. Giza 89 showed the least percentage reduction for shoot and root lengths, and total plant fresh and shoot dry weights with values of 4.9, 7.5, 2.5 and 0.44%, respectively, On the other hand, cotton cv. Giza 86 and 45 recorded the highest percentage reduction values for the same growth parameters. Based on root-gall index and R factor of M. incognita infecting cotton cultivars tested, Giza 89 was scored as resistant while Giza 45 as well as Giza 86 were scored as susceptible hosts since their root gall indices were 2, 5 and 4 with R factor values of 0.4, 2.31 and1.11, respectively.

The host suitability of ten medicinal plant species i.e. carnation, celery, coriander, dill, geranium, peppermint, periwinkle, rose geranium, thorn apple and thyme to Meloidogyne incognita infection indicated that none of the tested plant species was immune and the incidence varied from plant species to another. Their host category was determined through the relationship between host plant growth response (% reduction of total plant fresh weight) or gall index and nematode reproduction factor (RF). Carnation and thyme were rated as highly susceptible (HS) or susceptible (S) hosts, since their plant growth parameters were highly affected along with reproduction factor >1. Rose geranium was rated as moderately intolerant (IT) or moderately resistant (MR), since its plant growth character was moderately affected along with reproduction factor <1. Geranium was rated as fairly resistant (FR) or (MR), since its plant growth criterion was moderately affected with reproduction factor >1. Dill, celery, coriander, thorn apple and periwinkle were classified as resistant (R) or moderately resistant (MR)hosts, since their plant growth were not affected with reproduction factors <1, depending upon the host suitability designations used.

A greenhouse experiment was conducted to determined the impact of three organic materials i.e. sesame grounded seeds and pigeon manure as pre-planting applications as well as salicylic acid as foliar spraying either alone or mixed with oxamyl at their half doses each on M. incognita infecting tomato plant cv. Alisa comparing with oxamyl at the recommended dose under greenhouse conditions (27±3 o C). Pigeon manure alone or mixed with oxamyl at half doses overwhelmed other treatments in the increment values for total plant growth parameters and accomplished the highest percentage reduction of final nematode population, (95.4%), number of galls (93.7%), and egg-masses (94.4%), respectively. It is interesting to note that no significant deference between the three double treatments tested in plant length values that were amounted to 57.29, 57.29 and 54.16% for pigeon, salicylic acid and sesame plus oxamyl each at their half doses comparing to nematode alone. Nematode reproduction factors under the stress of sesame grounded seeds, pigeon manure and salicylic acid solely or mixed with oxamyl at their half doses each in comparing with oxamyl were adversely affected. Such rates ranged between 0.07-0.14 vs 2.41 for nematode alone. It was evident that N, P, K and OM concentrations were obviously reduced by nematode infection. All tested components specially pigeon manure plus oxamyl as pre-planting application showed remarkable increase in N, P, K, and OM concentrations exceeding those of nematode alone.

The influence of six essential oils i.e. garlic, sesame, neem, castor, chamomile, and linseed added to aseptic culture (MS medium) used for growth of tomato seedlings cv Strain-B before transplanting in pots with sterilized sandy loam soil on Meloidogyne incognita infection was studied under greenhouse conditions 30±5°C. Results indicated that all of the tested essential oils introduced into growth media protected and improved tomato plant growth of either the infected or uninfected with nematodes to a certain extent. Among all tested materials, castor oil gave the highest increment in fresh weight of the whole plant either infected or uninfected with values of 135.42% and 217.59%, respectively. The same trend was observed with castor oil in respect to increasing shoot dry weight of the healthy tomato plants (37.14%) whereas recorded the second to linseed oil treatment with the infected plants with values of 32.56% and 35.2%, respectively. Moreover, sesame oil application achieved the second values to castor oil treatment in increase percentage of both fresh weight of whole plant (132%) as well as shoot dry weight (29.24%), respectively. The highest reduction percentage in nematode population was obtained with castor oil treatment which amounted to 93.53% followed by linseed oil application with value of 92.71%. Among all tested essential oils, sesame oil significantly decreased number of galls on tomato roots with reduction percentage of 90%, followed by those treated with either chamomile or linseed oils with value of 87.5% each. M. incognita did not produce egg-masses on plants treated with all of the tested materials and considered as highly resistant due to egg-masses indices (zero each) whereas those received linseed oil as very resistant with egg-masses index value of 3 and reduction percentage value of 97.4%.

The role of spray application of three inorganic fertilizers MnSO4, ZnSO4 and CaCl2 at three concentration each viz: 50, 100 and 150 mg/l of the first two elements and 100, 200 and 300 mg/l for the latter fertilizer three times at one week interval in comparison with oxamyl at the recommended dose (0.39/plant) on development and reproduction of M. incognita infecting tomato plants cv. Castle Rock and plant growth was studied under greenhouse conditions (29±7ºC). Obviously all tested nutrient minerals with their concs. significantly improved plant growth parameters and reduced nematode criteria, respectively as well to great extent. Among the tested inorganic fertilizers, CaCl2 at 200 mg/l/plant overwhelmed other treatments, followed by that of MnSO4 at 150 mg/l in the increments values of plant growth parameters such as shoot dry weights (30 and 21.1%). whereas, ZnSO4 at 100 mg/l application had the lowest value (9.6%) in this respect, respectively. Similar trend was noticed regarding reduction of nematode criteria such as population density (90.8, 90.7 and 90.2%) respectively. Likewise, nematode multiplication was also affected by the tested nutrient elements performing the above trend, where CaCl2 at 200 mg/l and ZnSO4 at 50 mg/l/plant represented of minimum and maximum values that averaged 0.13 and 0.16 vs 1.39 for nematode alone respectively. N, P, K concs., chlorophyll and total phenol contents in leaves of tomato either infected with M. incognita or not as influenced by foliar spraying of the tested inorganic fertilizers were reported and discussed.

A pot trial was carried out to verify the impact of four grounded seeds i.e. caster, garlic, maize and sesame separately added as pre or post planting applications to tomato plants under the stress of Meloidogyne incognita infection in comparison with oxamyl in the greenhouse. Noticeably, data indicated that all tested organic materials as grounded seeds improved plant growth criteria and reduced nematode parameters as well. Using sesame grounded seeds as pre or post applications showed the maximum values of plant length (82.4 and 70.8%),total plant fresh weight (104.0 and 80.2%),shoot dry weight(65.5 and 65.5%),respectively. In the meantime, sesame grounded seeds accomplished the highest reduction percentage in numbers of eggmasses and galls / root system in this study. Caster application ranked second in this respect, whereas plant receiving the maize grounded seeds as pre-planting application gave the lowest amount values in enhancing plant growth parameters. It is evident that N, P, K, OM and O.C concentrations were obviously reduced by nematode infection with various degrees. All tested components showed remarkable increase in N, P, K, OM and O.C concentrations exceeding those of nematode alone.

The aim of this work was to evaluate the potential of certain soil organic matters i.e. poultry or horse manures or dried-leaf powders of periwinkle (Chatharanthus roseus) or castor (Ricinus communis) in comparison with oxamyl against Meloidogyne incognita on Egyptian cotton cv. Giza 45 in vivo. Five grams of each soil organic amendments were separately added to cotton seedlings cultivated in pots, as well as oxamyl at the recommended dose, one day before nematode inoculation process. Results revealed that all tested materials significantly improved plant growth parameters and reduced nematode population density, number of galls, females and egg-masses on roots of cotton plants. Of the tested organic matters, poultry manure achieved the highest percentage increase in plant length, shoot dry weight and fresh weight of whole plant with values of 54.4, 74.7and 37.2%, respectively, followed by perwinkle powder for the first two parameters with values of 51.0 and 65.9%, respectively, whereas, castor powder for the later parameter with value of 44.7% as compared with nematode alone. Moreover, oxamyl treatment ranked first in percentage increase values of shoot dry weight (87.9%) and fresh weight of whole plant (62.5%), respectively, and second to poultry manure treatment with value of plant length (58.0%) comparing to nematode alone. In addition, nonsignificant differences between all tested organic matters regarding nematode parameters were noticed. However, oxamyl application surpassed them in suppressing nematode population density (68.9%), number of galls (67.6%) and eggmasses (65.8%), respectively, as compared with nematode alone. Meanwhile, among the organic matters tested, pots received poultry manure showed the highest percentage reduction in nematode population density (53.3%), followed by horse manure (51.3%), then periwinkle powder (50.4%), and castor powder (49.4%), as compared with nematode alone. These results demonstrated the potential of such organic matters to protect cotton plant against M. incognita under greenhouse conditions.

The impact of nine medicinal and aromatic plant products as ground-oilseeds i.e. fenugreek, arugula, coriander, celery and dill; and dried leaf powders i.e. peppermint, rosella, periwinkle and throne apple separately in comparison with oxamyl on M. incognita infecting eggplant cv. Black Long under greenhouse conditions, indicated that all tested materials obviously improved plant growth parameters of eggplant plants and significantly diminished nematode development and reproduction. Fenugreek as ground-oil-seeds application represented the maximum percentage increase values of plant length (54.3%), total plant fresh weight (177%), shoot dry weight (142.7%) and number of leaves/ plant (117.4%) whereas ground-oil-seeds of dill gave the least percentage increase values in this respect. However, peppermint as powder also represented the maximum increase values of ameliorating plant length (53.6%) , total plant fresh weight (158.4%), shoot dry weight (138.8%) and number of leaves / plant (108.7%), respectively, followed by that of rosella and throne apple whereas periwinkle showed the least values of the same plant growth criteria. Oxamyl ranked first and surpassed other tested applications in percentage increase values of the same plant growth criteria, respectively, and in diminishing nematode criteria with the lowest reproduction factor (RF) value of 0.37 vs 4.6 for nematode alone. Fenugreek treatment overwhelmed other tested ground-oilseeds in suppressing nematode population density (81.1%), root galling (92.8%) and eggmasses number (92.0%), followed by arugula application. However, the least values of the same nematode parameters was achieved by dill ground-oil-seeds treatment. Moreover, peppermint treatment also surpassed other tested dried leaf powders of medicinal and aromatic plants in diminishing final nematode population (80.5%), number of galls (84.0%) and eggmasses (86.7%), followed by rosella powder (78.1, 84 and 84.4%) for the same nematode parameters, respectively. However, periwinkle powder gave the relatively low value of final nematode population density (60.5%) but with high % reduction values of number of galls (80.0%) and eggmasses (82.2%) than of throne apple in the latter two nematode criteria, respectively. Treatments of fenugreek and peppermint products represented the lowest values of RF that amounted to 0.86 and 0.89 vs 4.6 for nematode alone, respectively.