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Abstract Tomato ( Lycopersicon esulentum ) are considered one of the most important economic vegetable crops for export as well as its importances in food processing . These are grown in Egypt at different seasons through out the year in opened field and greenhouse especially in newly reclaimed desert land. They are subjected to the attack by several fungal, bacterial, viral and nematode diseases . Plant parasitic nematodes are one of the most important pests world wide especially root-knot nematodes (Meloidogyne spp. ) on tomato which considered one of the most economically important that cause great harmful effect on plants and losses in quality and quantity of yield . This study was carried out under laboratory and greenhouse conditions at the Faculty of Agriculture , Menoufia University Shebin El-kom, during the period 2015-2020 obtained results could be summarised as following : 1- Different bacterial isolates i.e. ( Bacillus megaterium and Bacillus subtilis ) and fungal isolates i.e. ( Trichoderma harzianum and Trichoderma spp.) were isolated from rhizosphere soil of healthy tomato plant roots and evaluated against root-knot nematode in vitro . 2- The effect of bacterial and fungal culture filtrates on egg hatching of Meloidogyne spp. was carried out in vitro .Results showed that using culture filtrates of both bacterial and fungal isolates reduced egg hatching percentage in vitro and the greatest egg hatching inhibition was recorded with Bacillus megaterium followed by Trichoderma harzianum , while the least one was Trichoderma spp. Isolate (2). 3- The effect of bacterial and fungal culture filtrates on larvae mortality of Meloidogyne spp. was carried out in vitro. Result showed that culture filtrates of all bacterial and fungal isolates significantly increased larvae mortality of Meloidogyne spp. in vitro. The greatest larvae mortality recorded with Bacillus megaterium followed by Trichoderma harzianum, while the least one was Bacillus sutilis isolate (4) and Trichoderma spp. isolate(2) . 4-The different biocontrol agents i.e. (Bacillus megaterium, Trichoderma harzianum , Bacillus subtilis and Trichoderma spp. ) were evaluated against Meloidogyne spp. on tomato plants . Results showed that application of bacterial and fungal culture filtrates were effective in reducing the nematode parameters i.e. number of galls , egg masses, females / root system and J2s /250g soil compared to the control on tomato plants occurred with Bacillus megaterium , followed by Trichoderma harzianum . Culture filtrate of B. megaterium was the best effective one in reducing significantly all related nematode parameters by 90 , 92 , 92 and 89% , respectively followed by T. harzianum isolates by 89, 91, 91 and 94%, respectively compared to nematode alone ( C+). The least effect noticed with Bacillus subtilies isolate (1) and Trichoderma spp. Isolate(1). 5-Application of bacterial and fungal culture filtrates were effective in enhancing tomato plant growth parameters i.e. fresh shoot and root weights (g) ,dry shoot weight (g), shoot and root lengths (cm) compared to treated plants with nematode alone . The greatest significant enhancement was recorded with B .megaterium by 180 ,144 , 114 , 180 and 225% , respectively and T. harzianum by 160 , 133 , 100 , 169 and 104% , respectively , whereas the lowest one was recorded with Trichoderma spp. Isolate (1) by 35, 44, 28.6, 21 and 93 73% ,respectively. 6- Arbuscular mycorrhizal fungi at different doses i.e. (0.5 , 1 ,2 or 4%) and different application times ( one week before , at the same time and one week after nematode inoculation ) were evaluated on nematode parameters of tomato plants infected with Meloidogyne spp. Results showed that all different doses of arbuscular mycorrhizal fungi significantly reduced all the nematode parameters i.e. number of galls, egg masses,. females / root system and number of J2 /250g soil compared to the plants treated with nematode alone. Application of AMF at 4% one week before nematode inoculation reduced the nematode parameters by 84 , 88 , 87 and 89 %, respectively ,followed by mycorrhizae at the same time by 82, 85, 84 and 84% and one week after nematode inoculation by 80, 84, 84 and 83% . The least one was achieved by mycorrhizal fungi at (0,5% ) when applied at one week after nematode inoculation by 24 , 25 , 28 and 5% respectively compared to nematode alone. 7-using mycorrhizal fungi at different doses i.e. (0.5 , 1 ,2 or 4%) and different application times ( one week before , at the same time and one week after ) on plant growth parameters i.e. fresh shoot and root weights (g) ,dry shoot weight (g), shoot and root lengths (cm) of tomato plants infected with nematode . Results showed that all different doses of arbuscular mycorrhizal fungi were effective in increasing all vegetative plant growth parameters . The greatest effect recorded with the highest application concentration 4% and the application time of one week before nematode inoculation by 210 , 134, 203, 121 and 86% , respectively, followed by at the same time of nematode inoculation by 145, 108, 173, 117 and 79 % respectively, followed by the application time of one week after nematode inoculation by 133 , 103, 142, 116 and 63 % , respectively. The lowest effect recorded with mycorrhizal fungi at (0.5%) when applied one week after nematode inoculation 6 , 15, 30, 65 and 5 % , respectively. 8-Results also revealed that all mentioned obvious doses of arbuscular mycorrhizal fungi were effective in increasing the activities of antioxidant enzymes i.e. phenoloxidase and peroxidase in tomato plants infected with Meloidogyne spp. compared to untreated plants. 9-Effect of mycorrhizal fungi at different doses and different application times combined with Meloidogyne spp. on mycorrhizal infection % in tomato roots No. of spores / 100g soil were studied. results showed that inoculation of the plants with Meloidogyne spp. enhanced the root infection with mycorrhizal fungi after 60 days from nematode inoculation compared to the plants treated with nematode alone . The highest enhancement of mycorrhizal infection (100%) was observed after 60 days from nematode inoculation at 4% of soil weight at all application times . 10-The integration control of Meloidogyne spp. on tomato plants by using direct and indirect effect of the effective treatments were evaluated. Results of direct effect showed significant reduction in all nematode parameters i .e . galls , egg masses and females / root system , as well as number of nematode juveniles . The greatest reduction in nematode parameters was recorded with the treatment of B. megaterium +T.harzianum + AMF 4% + Nematode by 97, 97, 97 and 95% respectively, followed by the treatment of B. megaterium + AMF 4% + Nematode by 95, 96 , 95 and 93% ,respectively and (T.harzianum + AMF 4% + Nematode ) by 94 , 94 , 94 and 90 % ,respectively . 11-The integration control of Meloidogyne spp. on tomato plants by using indirect effect (split- root system) showed that the treatment of ( B. megaterium + T. harzianum + AMF4% ) was the best treatment in controlling root- knot nematodes . The greatest reduction in galls, egg masses , females/ root system and J2 s / 250 g soil were recorded with the treatment of B. megaterium +T. harzianum + AMF 4% + Nematode by 93, 94, 93 and 95% , respectively , followed by B. megaterium + AMF 4% + Nematode by 92, 92 , 92 and 92% respectively and T .harzianum + AMF 4% + Nematode by 90 , 91 , 90 and 90 % respectively , whereas the lowest one recoreded with (T. harzianum + Nematode) by 77, 78,78 and 69%, respectively. 12-The treatment of ( B. megaterium + T.harzianum + AMF4%+Nematode) was the most effective one in enhancing fresh shoot and root weights , dry shoot weight , root and shoot length compared to untreated control plants . The greatest encourgement was recorded with the treatment of B. megaterium + T.harzianum + AMF 4% + Nematode by 163 , 160, 150, 66 and 117%, respectively, followed by the treatment of B. megaterium + AMF 4% + Nematode by 138 , 140 , 117, 55 and 92% , respectively. The lowest effect recorded with the treatment of T.harzianum + Nematode by 50 , 40, 33, 20 and 25% respectively, compared to the plants treated with nematode alone . |