This study aimed to estimate the virulence of an indigenous Beauveria bassiana on all developmental stages of two indigenous coccinellids; Coccinella undecimpunctata and Hippodamia variegata through three application methods; direct spray, contact method, and feeding on aphids treated with the fungus (ingestion). Also, indirect effect on all developmental stages resulted from 1st larval instar treated with these application methods. All treatments were done with a concentration of 1 × 105 which was recommended in previous studies for different aphid species with a control of 0.02% Tween 80 (v/v). The mortality of 1st larval instar of both H. variegata and C. undecimpunctata and pupal stage of C. undecimpunctata were significantly increased with spray method only. Also, contact method achieved significantly higher mortality on 1st larval instar of C. undecimpunctata only. Regard to indirect effect, except of mortality of 1st larval instar of both predators and 2nd larval instar of H. variegata, other developmental instars/stages of both predators were not affected by B. bassiana through the three tested application methods in the mortality, duration, survival, cumulative survival male and female longevity, and fecundity. Therefore, both tested predatory coccinellids could be compatible with this indigenous isolate of B. bassiana where, in general, there are no negative effects of the fungus on both predators.

The endophytic fungus, Beauveria bassiana has been found to occur endophytically in hundreds of plant species tissues and has been inoculated for establishment in different plants. It has negative effect on piercing-sucking insects in grapevine plants. Thus, the present study aimed to detect the endophytic fungus, B. bassiana throughout ITS genes analysis in the grapevine plant, Vitis venifera cv. Taify and assess its potential for controlling the grapevine aphid, Aphis illinoisensis Shimer (Hemiptera: Aphididae). The obtained 5 isolates were DNA sequenced for ITS region. Data analysis showed that there were 2 different isolates (accession number: MN900613 for isolate Bb-Taif1 and MN900614 for isolate Bb-Taif2). The values of LC 50 were 6.041 × 10 4 , 3.199 × 10 5 spores/ml while those of LC 90 were 6.13 × 10 6 and 7.474 × 10 7 spores/ml after 3 days of treatment by Bb-Taif1 and Bb-Taif2, respectively. These values showed that the virulence of Bb-Taif1 isolate was higher in its efficacy than the Bb-Taif2 isolate. Further investigations are needed to evaluate its efficacy on other piercing sucking or chewing insect pests throughout conidia spraying, soil inoculation, and/or root immersion for grapevine plants.

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Aim: The current study aimed to characterize the composition of endophytic fungal communities related to Taify grapevine leaves. Methodology: Taify grapevine leaves were collected from three different locations at Taif region. Total DNA was extracted and the endophytic fungal communities were investigated using next generation sequencing in a metagenomics approach. Results: The obtained data detected 26 fungal operational taxonomic units (OTUs) in all locations with variation in most taxa among three locations. The phylum Ascomycota dominated relative sequence abundance (90.83%), followed by Basidiomycota at 1.82%. Other unidentified fungi at phylum level dominated 7.35% abundance level. At genus level, Alternaria and Cladosporium genera were present at all locations, while Filobasidium and Didymella were detected in two locations. Most genera, Penicillium, Hanseniaspora, Fusarium, Chrysocorona and Quambalaria were detected in one location only. Interpretation: The present study confirmed the diversity of endophytic fungi in Taify grapevine, including pathogenic and non-pathogenic species. The detected species have potential to be used as biocontrol species against economically important pathogens such as Alternaria and Hanseniaspora. This will contribute to our understanding of grapevine-endophytic fungi interaction and their utilization to enhance grapevine production and quality. Key words: Endophytes, Fungi, Grapevine, Metagenomic, Next generation sequencing

In an attempt to develop a cost-effective process for bioinsecticide production by B. thuringiensis, the feeding regime during aerobic cultivation of the bacterium was investigated and optimized. The process was designed as a two-stage process; a first stage of active growth, where glucose and other nutrients were adequately supplied to the growing cells over 12 h, followed by a second stage of 2 h for spore formation and toxin release. In order to maximize spore and toxin yield and productivity, different quantities of glucose and nutrients were fed separately to the growing cells in four different fermentation runs. In all runs, glucose was converted to bacterial biomass during the first stage and subsequently to spores and crystal protein during the second phase. The best results were obtained with a fermentation run supplied with 190 g glucose in 1500 ml. Up to 20.1 g of bacterial insecticides/l were recovered from fermentation broth with a glucose to toxin conversion yield of 0.159 g/g. Also, a markedly high spore concentration of 2.31 9 10 12 c.f.u./ml was obtained. The spore-crystal protein mixture obtained was tested for its insecticidal activity against three of the most agronomically important pests. Among the bioinsecticide-treated insect pests, Egyptian cotton leafworm, Spodoptera littoralis was the most susceptible pest with the lowest LC 50 of the bioinsecticides against its larval instar and the highest virulence against adults emerged later on from the surviving larvae.