The main goal of this study was enhancing the biocontrol activity of Trichoderma spp. (T. harzianum, T. koningii, T. viride, and T. virens) against Cephalosporium maydis, the cause of late wilt disease in maize. Five isolates of C. maydis were isolated from diseased maize plants, showing late wilt symptoms, and were collected from infected maize fields in Gharbia Governorate, Egypt. Pathogenicity test revealed that all C. maydis isolates were able to attack maize plants (cv. Baladi), which cause late wilt disease. Isolate 3 (Cm3) was the most virulent of them. In in vitro experiments, vegetative growth of the mycelium of C. maydis was highly inhibited after opposite sides' treatment by Trichoderma species on Potato Dextrose Agar plates amended with Chlorella vulgaris extracts (cool and hot extracts) than unamended one. Formulation of C. vulgaris extracts and Trichoderma spp. were prepared. The formulations maintained the capacity of Trichoderma spp. to inhibit growth of the pathogen for up to 1 year when stored at both room temperature or at 7°C. These formulations (3-day-old) were examined for biological control activities against late wilt disease of maize. Under greenhouse and field conditions, all treatments reduced late wilt incidence compared to the untreated control. Treatments involved Trichoderma spp., and C. vulgaris extracts were more effective than that used individually. Both of the C. vulgaris extracts, with each of T. virens and T. koningii, were the most effective treatments in this respect. Under greenhouse conditions, formulation treatments (C. vulgaris extracts and Trichoderma spp.) significantly increase the plant growth of maize plants, i.e., plant height and plant dry weight as compared to the non-treated control either in infested or in un-infested soil with C. maydis. Under field conditions, these formulations increased the grain yield as well as ear parameters as compared with either C. vulgaris extracts or Trichoderma spp. alone as well as non-treated control. This study suggests that the efficacy of Trichoderma spp. was enhanced with C. vulgaris extracts and these formulations can be developed as bio-fungicides for minimizing the late wilt disease caused by C. maydis in maize.

Background: Damping-off and root rot/wilt diseases caused by the soil-borne fungi Fusarium solani and F. oxysporum are a serious problem of dry bean productions in Egypt. This study examines the potential of controlling these diseases biologically by using three Trichoderma isolates, compatible with the fungicide thiophanatemethyl, i.e., T. harzianum, T. viride, and T. virens. Soil application with inoculants containing these isolates employed either alone or in combination with seed coating with thiophanate-methyl was applied. Results: Under greenhouse and field conditions, all treatments significantly reduced the incidence of damping-off and root rot/wilt diseases and increased the percentage of survival plants. These treatments increased vegetative growth parameters and yield components of the survival dry bean plants compared with untreated control. Soil application with Trichoderma isolates combined with thiophanate-methyl seed treatments was more effective than using both of them individually. Meanwhile, T. virens + thiophanate-methyl was the most effective treatment. The tested treatments stimulated systemic defense responses in dry bean plants by activating defense enzymes including peroxidase, polyphenoloxidase, and chitinase. Conclusions: Based on the obtained results, compatible isolates of Trichoderma spp. as soil treatment combined with thiophanate-methyl as seed treatment may have potential to develop a new biofungicide for integrated management of damping-off and root rot/wilt diseases in dry bean.

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Dracaena sanderiana, of the family Liliaceae, is among the ornamental plants most frequently imported into Egypt. Typical anthracnose symptoms were observed on the stems of imported D. sanderiana samples. The pathogen was isolated, demonstrated to be pathogenic based on Koch's rule and identified as Colletotrichum dracaenophilum. The optimum temperature for its growth ranges from 25 to 30 °C, maintained for 8 days. Kemazed 50% wettable powder (WP) was the most effective fungicide against the pathogen, as no fungal growth was observed over 100 ppm. The biocontrol agents Trichoderma harzianum and Trichoderma viride followed by Bacillus subtilis and Bacillus pumilus caused the highest reduction in fungal growth. To the best of our knowledge, this report describes the first time that this pathogen was observed on D. sanderiana in Egypt.

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Background: Strawberry (Fragaria ananassa Duch.) is an economically important crop in Egypt. Yet complex black root rot disease of strawberry caused by Fusarium solani, Rhizoctonia solani, and Pythium sp. can cause considerable yield losses. Therefore, this study aimed at evaluating different aspects of soil solarization against this disease. Such an evaluation would better be viewed in the context of other beneficial effects of soil solarization on nematodes and weeds. Materials/methods: Growth agar disks, growth suspension, and resting stages of strawberry black root rot fungi were evaluated at different temperatures and exposure times using digital hot water bath. Cloth bags artificially infested with single fungal species were buried into the soil before soil solarization at soil depths of 1-10, 11-20, and 21-30 cm at three spots of each plot for each of the abovementioned fungi for 3, 6, or 9 weeks. The disease incidence and severity in solarized and un-solarized soil was compared with the application of the fungicide Actamyl. Effects of soil solarization on nematodes and weeds were also consulted. Results: The lethal temperature to F. solani, Pythium sp., and R. solani was 58, 58, and 56°C, respectively when exposure time was 1 min. Chlamydospores were killed at 62°C while sclerotia were killed at 58°C in hot water for 1 min. Maximum soil temperature in solarized soil was raised by 15, 14, and 12°C at depths of 1-10, 11-20, and 21-30 cm as compared with non-solarized soil. Solarization for 3, 6, and 9 weeks significantly reduced the disease incidence and severity and increased the strawberry yield. Complete reduction in total count of all tested fungi was obtained after 9 weeks at all tested depths. A review of collective soil pest and pathogen control via solarization documented its beneficial application. Conclusion: The study may exploit hot months in Egypt for soil solarization against the serious root rot disease either singly or in an integrated pest management program.