Examination was done at preliminary bracketing bioassay on one old 4th nymphal instar of desert locust. Results showed that two isolates, namely NDL1 and NDL2 were having highly potentiality as entomopathogenic bioagents. Thirty isolates were isolated from dead/ infected nymphs of desert locust occurred in raring cages at Department of Locust and Grasshoppers Research, Plant Protection Research Institute, Agricultural Research Center, Dokki, Giza, Egypt. Molecular identification of isolated bacteria was done using universal primers of 16s rRNA, followed by DNA sequencing. Nucleotides were blasted at (https://www.ncbi. nlm.nih.gov /genbank/) to recognize that NDL1 and NDL2 isolates were two different isolates of Bacillus cereus with a high similarity (100%).  Susceptibility of 4th nymphal instar of Schistocerca gregaria (Forskal) to the isolated B. cereus was determined using two bioassay procedures, Leaf-dip and per os. The insecticidal activity of both isolates against locust nymph in leaf dipping showed that NDL2 was more efficient than NDL1. However, the opposite trend was observed in using per os.  Both Isolates have the potential to be a successful biocidal agent to control desert locust.

Ninety nine yeast isolates were isolated from surface of apple, grape, orange and tomato fruits. The isolates were tested in vivo in preliminary study for biocontrol potential against green mould of navel orange fruit. According to primary screening, twenty two isolates were selected to continue the secondary screening (phase one) using different concentrations of the washed yeast cells in water suspension to evaluate their biocontrol efficacy at 21±1°C. Among twelve yeast isolates were passed to the secondary screening (phase two) at 7±1°C, washed cells of yeast isolates CT 503, CT 507, CT 508, CT 512 and CT 550 at 1x109, 2x108 and 1x108 CFU/ml produced complete protection for 21 days to wounded navel orange fruits inoculated with spore suspension of Penicillium degitatum  (1x104 conidia /ml).  Meantime, no lesions developed on the navel orange fruits treated with the yeast isolates CT 503, CT 507 (Debaryomyces hansenii var. hansenii strain C) and CT 512 (Endomycopsella vivi) at 6.6x107CFU/ml, while the percentage of rot reduction of the isolate CT 550 (Candida edax) was 99.81%. Culture filtrate of twenty two different yeast isolates used in secondary screening (phase one) did not prevent decay of wounded navel orange fruits but had an inhibitory effect on rot development. The relative abilities of the promising yeast isolates (CT 503, CT 507, CT 512 and CT 550) to induce disease resistance against P. digitatum on navel orange fruits were studied. Inoculation of promising yeast isolates significantly triggered induction of resistance in navel orange fruits. The lesion diameters of green mould 66 hours later after inoculation by spore suspension of P. digitatum  in a neighbouring wound that was made approximately 6 mm away from the initial woundwhich inoculated withthe isolates CT 512, CT 550, CT 507 and CT 503 were reduced by 25.5%, 20.5%, 16.7% and 14.1%, respectively. In this respect, there were no significant differences among the three different isolates CT 503, CT 507 and CT 550.

The evaluate some safety treatments including: mulching, tunnels, natural yeast extract, antioxidant and two rhizobacteria Serratia marcescens and Pseudomonas fluorescens towards root-knot nematode Meloidogyne spp. on strawberry plant grown in naturally infested soil and consequently their probable effects on growth parameters, chemical components and yield of strawberry compared to untreated control. Results of this study confirmed that all used treatments, significantly reduced all related nematode parameters i.e. number of galls/root system; number of egg masses/root system as well as number of juveniles/250 g soil (either after 2 or 4 months) when compared to plants grown in the naturally infested soil only. The highest percentage of reduction in all related nematode parameters were noticed after 4 months. Mulching, S. marcescens, P. fluorescens and tunnels, played an important role in reducing the percentage of nematode parameters. Mulching and S. marcescens reduced the percentage of gall numbers/root system by 77%, followed by tunnels by 75% and P. fluorescens by 70%. S. marcescens reduced the percentage of egg masses/root system by 80% followed by P. fluorescens by 78% and mulching by 76%. Results indicated that the soil treated with mulching, also significantly reduced the percent age of juvenile numbers/250 g soil by 79% followed by S. marcescens by 73%. . Results revealed that all previous treatments significantly increased the early and total yield. Our results confirmed that, the rhizobacterium S. marcescens came in the first rank as a promoter of all related plant growth characters, followed by tunnels and mulching treatments. Results confirmed that also the antioxidants, are considered the effective one in enhancing the activities of peroxidase and phenoloxidase as well as T:S.S% and V.C followed by the natural yeast extract.

Different applications [various potato cultivars, chemical fertilizers, bioagents and chemical in-ducers] were used for controlling brown rot dis-ease of potato. Potato cultivars namely Diamant, Desiree, Herms, Lady Joy, Lady Rossetta, Nicola, Spunta and Valor were variably susceptible to Ralstonia solanacearum, the causal pathogen of brown rot disease. Herms cultivar was the least susceptible. Application of ammonium sulfate, potassium sulfate, Urea, and calcium superphos-phate to infested soil as a single amendment re-duced disease incidence. Application of calcium superphosphate was the most effective treatment. The bioagents Pseudomonas fluorescens, Pseu-domonas putida and Bacillus subtilis were effec-tive in controlling disease when were used sepa-rately and Pseudomonas putida was the most effi-cient. Foliar spraying with different inducers sin-gly [salicylic acid, di-potassium hydrogen phos-phate and tri-potassium phosphate] reduced the disease incidence. Tri-potassium phosphate was the most effective against the disease. Therefore, a management programme was suggested including cultivar Herms, calcium superphosphate, Pseudo-monas putida and tri-potassium phosphate, as in-tegrated treatment. Rotation of these agents showed high effectiveness to disease control as well on the yield increase.

Several nurseries of olives in Fayoum and Giza were surveyed for root rot incidence during early summer of 2003. In Fayoum, root rot incidence reached 53% while in Giza, disease incidence was 44%. Disease symptoms consist of partial wilting, leaves browning and twig dieback, which was associated with severe root rot and basal stem cankers and followed, in most cases, by plant decline and death. The most frequently isolated fungi from rotted roots were Fusarium oxysporum, F. solani, F. moniliforme, Rhizoctonia solani, Sclerotium rolfsii, Cylindrocarpon sp.  and Alternaria alternata. Isolation frequency of different fungi varied among olive cultivars. Generally, Fusarium spp. were the most frequently isolated  pathogens and Fusarium oxysporum was the most frequent (35.5%) on all cultivars followed by F. solani (19.3%) R. solani (16.1%). Meanwhile, S. rolfsii, F. moniliforme, Cylindrocarpon sp. and A. alternata occurred at lowfrequencies. Pathogenicity tests showed that all tested isolates caused varied degrees of root rot symptoms on olive transplants, cvs. Manzanillo and Picual. Fusarium oxysporum, F. solani and R. solani caused the highest root rot incidence and severity on both cultivars. There was a positive correlation between disease severity on roots and severity of foliar symptoms. All evaluated olive cultivars were susceptible or extremely susceptible to fungal pathogens. All cultivars showed high disease severity with root rots, especially in response to infection by F. solani, F. oxysporum and S.  rolfsii. However, the least foliar symptoms were recorded on cultivar Coratina. Application of two commercial biological control products (Rhizo-Plus and Trichoderma 2000) to soil, 24h before planting olive cuttings in the nursery, significantly reduced incidence of root rot on transplants of cultivars Manzanillo and Picual, up to 28 weeks after planting

Preparationof either Bacillus thuringiensis or Trichoderma harzianum  were used as seed coating or soil application for management of root-knot and root rot disease complex caused by the root-knot nematode, Meloidogyne javanica and the fungus Rhizoctonia solani on soybean plants. Number of galls, root galling, egg masses and disease severity were reduced sharply on plants treated with both biocontrol agents, either as seed or soil application compared with non-treated plants. Soil application with both biocontrol agents was the best method in reducing nematode and fungus disease severity. Plant growth parameters i.e. fresh shoot and root weight, dry weight and number of pods and bacterial nodules were markedly increased with all treatments of biocontrol agent either with seed or soil treatment compared to plants grown in infested soil with either pathogens alone or combined. Results show that plant survival was more affected when R. solani was alone or combined with M. javanica. Seed coating was considered the effective method in increasing survival plants. The biochemical analysis of treated plants with both biocontrol agents were affected compared to non-treated plants grown in pathogen infested soil. The biochemical parameters i.e. chlorophyll A and B, carotein, phenols and amino acids were enhanced in bioagent treated plants compared to non-treated plants