The ecosystem is considerably affected due to the extensive use of chemical pesticides and fertilizers. As an alternative strategy, this study aimed to assess the biocontrol potential of the bioagents arbuscular mycorrhizal fungi and plant growth-promoting Trichoderma harzianum MZ025966 against tomato root-knot nematodes (Meloidogyne javanica). T. harzianum showed a great potentiality to produce indole acetic acid (IAA) (12.11 ± 2.12 μg/mL) and exhibited a noticeable activity of ammonification. Furthermore, T. harzianum revealed protease and lipase enzymatic activity of 28.36 ± 2.82 U/mL and 12.30 ± 0.31 U/mL, respectively, which may illustrate the control mechanism of nematode eggs and juveniles. As in mycorrhizal and/or T. harzianum inoculated tomato plants, the penetration rates of nematodes, as well as the number of juveniles, females, egg mass, and galls were significantly reduced. The lowest number of juveniles was observed in the case of either single mycorrhizal inoculation (45%) or in combination with T. harzianum (55%). The enzymatic activity of glutathione peroxidase and catalase was enhanced in tomato plants inoculated with the bioagents to overcome the negative impact of nematode parasitism. Our results proved that the application of biocontrol agents not only reduced the nematode population and penetration rate but also improved the plant growth, increased the nutritional elemental content and stimulated the plant’s systematic resistance.

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The effect of high hydrostatic pressure (HHP) treatments on chemical composition, proteolysis, rheological properties, total free amino acids and organoleptic properties for Cheddar cheese during ripening at 8-10 o C up to 120 days were evaluated. Application of HHP-treated Cheddar cheese at three levels (200, 400 and 600 MPa at 25 o C for 20 min.) was carried out as a methods for acceleration of Cheddar cheese ripening. Results showed that HHP-treated at 600 MPa for 20 min. at 25 o C was significantly higher in moisture, fat in dry matter and pH values, on the other hand total solids, was significantly lower throughout the ripening period followed by cheeses treated at 400, 200 MPa for 20 min. and control cheeses, respectively. All Cheddar cheeses treated with HHP showed significant (P≥0.05) higher increase in nitrogen fractions (WSN/TN% and NPN/TN%) than control cheese during ripening up to 120 days. Morover, total volatile fatty acids was significantly higher (P≥0.05) in cheese treated at 600 MPa than other cheeses during ripening. Rheological properties indicated that, HHP-treated Cheddar cheese at 600 MPa for 20 min. The significant lower (P≥0.05) values of hardness as compared to cheese treated at 200, 400 MPa and control cheeses. lowest values of chewiness and gumminess were observed in cheese treated at 200 and 400 MPa at the end of ripening. Also, HHP-treated Cheddar cheese at 600 MPa had a higher levels of total free amino acids than other cheeses treated at 200, 400 MPa and control cheeses,. HHP-treated Cheddar cheeses gained significantly higher flavour and texture scores compared to control cheese, but HHP-treated Cheddar chees at 600 MPa for 20 min. showed higher total scores than other cheese treatments.

This study aimed to investigate the impact of two isolates of Bacillus simplex (PHYB1 and PHYB9) for controlling the root rot disease of black cumin (Nigella sativa) caused by Fusarium camptoceras (PHYF1) under greenhouse and field conditions at Assiut Governorate, Egypt. The highest reduction percentage of infection (22.5%) was recorded by the treatment of PHYB1 as suspension than the control (60%). Both isolates of Bacillus spp. provided the root and foliar dry weight under greenhouse and seed production in the field. The results showed that the isolate PHYB1 as a formulation gave the highest impact in the root dry weight (0.28 g/plant), followed by PHYB9 (0.22 g/plant), with insignificant difference between them. PHYB9 suspension also provided the highest seed production (27.97 g/plant), whereas PHYB9 as a formulation gave the lowest (24.08 g/plant). Studies on the interaction between Bacillus spp. on F. camptoceras by scanning electron microscope (SEM) revealed that both caused a complete mycoparasitism on the fungal growth. The bacterial growth was seen to adhere and colonize the hyphae, resulting in hyphal tissue maceration. Therefore, the use of both isolates of Bacillus spp. to control root rot disease of black cumin under greenhouse and field conditions can be recommended.