The nematicidal effect of three marine algal, Ulva fasciata Delile (UF) (green algae), Corallina mediterranea, Corallina officinalis (red algae), extracts on egg hatching and second-stage juveniles (J 2 ) mortality of root-knot nematode (Meloidogyne incognita) in vitro compared to the nematicide activity of Oxamyl 24% SL (5 ml/l) was investigated. Results revealed that all treatments at the applied concentrations suppressed the egg hatching in 3 days. In details, the algal strain Ulva fasciata Delile extract showed the highest activity in decreasing the eggs hatchability after 3 days with 87%. Consequently, all treatments significantly increased the mortality of J 2 larvae after 12, 24, and 48 h compared to the control treated with distilled water. Under greenhouse conditions, all treatments in inoculated soils cultivated with tomato plants had reduced numbers of galls, egg-masses/plant, and the number of J 2 /250 g than the non-inoculated soil. The algal extract and the Oxamyl 24% SL (5 ml/l) increased the length and fresh weight of plant shoots and roots than the untreated. However, there were no differences in shoots and roots fresh weights and their lengths in the plant treated with Oxamyl 24% SL (5 ml/l) or the extracts of U. fasciata and Corallina officinalis. These results were closely similar to control. Both of peroxidase and polyphenol enzymes activity for the control plants remained relatively stable, while the activity of the two enzymes in the plant inoculated with the nematode decreased during 2 to 18 day post inoculation (dpi). These activities increased in inoculated plants treated with C. officinalis, C. mediterranea, and U. fasciata extracts and the other plants treated with Oxamyl 24% SL (5 ml/l). The maximum activity of the three enzymes was recorded at 5 dpi after treatment with U. fasciata.

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The present study was carried out in order to investigate the efficiency of various formulations of silver-botanical nanoparticles, i.e. cloves, lantana camara and conyza dioscoridis as nematicide substitutes against the tomato rootknot nematode (M. incognita), in both laboratory and under greenhouse conditions. Results clarified that the tested normal and NE-extracts, significantly and drastically, increased (J2) mortality % and reduced egg-hatching and the effect increased with increasing compound concentration and exposure time. However, nanoparticles forms of all tested compounds consistently showed higher effect than normal extracts forms. Meanwhile, NP-L. camara showed the highest J2 mortality % and egg-hatching inhibition at all exposure times. The nanoparticles, dramatically reduced root galls, egg masses, eggs and final population of M. incognita infecting tomato plants at the application rate of 100 μg/ml. Meanwhile, the NP-L. camara treatment was the most efficient in reducing root galls, egg masses, eggs and population of J2 in soil, followed by NP-Cloves and NP-C. dioscoridis. Moreover, the different extracts treatments improved and increased the mean values of tomato growth parameters in the inoculated treated plants. NP-L. camara showed the highest growth parameters. However, most mean values of growth parameters for NP-Cloves treatment not significantly different from the NP-L. camara. Consequently, these nanoparticles extracts could be effective potentially and environmentally safe to control tomato knot-root nematode.

The aim of this work is to study the effect of Paecilomyces, Bacillus and Trichoderma as a biocontrol against M. javanica and treatment times of biological control application on pepper under greenhouse conditions. A total of 75 plastic pots were divided into seven experimental groups. The first group was kept without infection as healthy control. Two weeks later, the pots of the other groups were inoculated with roughly 5000 eggs and j2 / pot. The second group, which acted as an infected control, was kept without treatment The third to sixth groups were treated with bioagents (Paecilomyces (P.), Bacillus (B.), Trichoderma (T.) and Paecilomyces + Bacillus+ Trichoderma (P.B.T.), respectively. The 7 th group received Vydate (nematicide). The 3 rd to 6 th groups were divided into three subgroups which received biological treatments at three phases (Before-With-After) infection. These four biological control treatments induced a significant decrease in disease parameter compared with control. The highest re-duction% in galls, egg masses and number of J2/250 cm3 of soil was obtained with Vydate application followed by those obtained with P.B.T when applicated before-, with-and after-infection then Paecilomyces when applicated before-and with-infection than the other treatments. All of the tested biological controls caused significant increases in the growth parameter of pepper (GPP). Highest GPP was obtained with biological control application before-and with-infection.