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Potential the biological or chemical control of lettuce white rot and maintain productivity
2020
Samuel Allah | Ahmed Abou El-Yazeid | hany gamal | ahmed bondok
The experiments were executed on the autumn and the winter of (2016 /2017, 2017/2018) seasons at Qalyub area, EL-Qalyubia governorate, Egypt. The main objective for this study to find out the efficacy of several biological and the chemical controls on growth and productivity of lettuce crop and management on white rot disease caused on Sclerotinia sclerotiorum. Thus, four treatments were applied as follow 1- the control (water application),2- Trichoderma asperellum, 3-Salicylic acid and 4- Calcium Chloride, which were evaluated and compared for the three fungicide as follow : 1- Iprodione , 2- Tebuconazole with Fluopyram and 3-Tebuconazole at the doses (85 & 100 ; 200 &100 and 50 &100 g or ml / 100L-1 respect.) . Which they tested for their ability for increasing the lettuce crop productivity and suppress mycelial growth of S. sclerotiorum pathogen by treatments were sprayed on two times on plants at (15-19 BBCH) stages by using backpack sprayer by 250 L./Fed.). Results indicated that, Iprodione applications significantly gave the highest indications of total and the Marketable yield in compared with the other experimental treatments for both seasons. Moreover, the two times of sprayes by Iprodione and Salicylic acid treatments had significantly lowered the disease incidence and disease severity and increasing the control efficiency in the both seasons. Whereas, the other treatments, Tebuconazole with Fluopyram or Tebuconazole and Trichoderma asperellum had a moderate effecacy on the lettuce crop productivety or the disease severity and incidence of Sclerotinia sclerotiorum in compared to the control treatment. In the contrast, application by Calcium Chloride had a low effect on the average yield or final yield as a mass and marketable plant in the both seasons and had insignificant effect on the disease severity or incidence of S. sclerotiorum despite low to medium recovery following applications. Finally, the control treatment was the lowest.
显示更多 [+] 显示较少 [-]APPLICATION OF SOME STRAINS OF FLUORESCENT PSEUDOMONADS IN MANAGING ROOT-INFECTING PATHOGENS OF MAIZE
2018
O. Abdel Azeez | Enas Hassan | E. El-Assiuty | E. Ramadan
Possibility of manipulating some of the efficient strains of fluorescent pseudomonads to manage the root-infecting pathogens of maize was studied throughout this study. Out of 110 isolates 24 of Pseudomonas species, recovered from the plant rhizosphere showed to have inhibitory effect against two major root-infecting pathogens of maize, namely Cephalosporium maydis and Fusarium verticillioides in vitro. Pot experiment revealed that just 4 isolates could reduce infection with both pathogens and enhance the plant growth as well. Based on the genotypic identifications of these four isolates showed that they were: Pseudomonas putida strain Pau9, P. putida strainPau11, P. putida strain Psf3 and P. aeruginosa strain Psf9.
显示更多 [+] 显示较少 [-]PHYSIOLOGICAL RESPONSE OF STRAWBERRY GROWN IN ROOT- KNOT NEMATODE INFESTED SOIL UNDER DIFFERENT SAFETY CONTROL APPLICATIONS
2011
M.E Mahdy | Midan Sally A.
Two successive field experiments during two seasons of 2008 and 2009, were carried out to 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 percentage of juvenile numbers/250 g soil by 79% followed by S. marcescens by 73%. Results confirmed also that all used treatments significantly increased all related plant growth characters viz. leaves, stems, root fresh and dry weight; plant height, leaves number, root length as well as false stem length. Moreover, these treatments significantly increased the activity of some oxidative enzymes e.g. peroxidase and phenoloxidase as well as some other chemical components i.e. total soluble solids (T.S.S %) and vitamin C (V.C). 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
显示更多 [+] 显示较少 [-]Efficiency of Three Bacterial Strains Against Tetranychus urticae Koch (Acari: Tetranychidae) Under Laboratory Conditions
2021
Heba Emam
This study was conducted to evaluate the efficiency of three bacterial strains Pseudomonas aeruginosa, Bacillus subtilis and Lysinibacillus spaericus against adult females of Tetranychus urticae Koch using spraying and dipping techniques with concentrations (101, 103, 105, 107 cfu. ml-1). The mortality percentages were calculated and numbers of each stages resulting from the live treated females were recorded. The symptoms that appear on treated female's mites as a result of death under laboratory conditions were recorded and photographed. The results revealed that, P. aeruginosa caused the highest mortality percentage of adult females T. urticae 100% after 72h at concentration 107 cfu. ml-1 by spraying application. Whereas the mortality percentage which recorded by the dipping technique was 54.58±1.71. B. subtilis also, was recorded increased the average mortality percentage of female T. urticae as it reached 73.33±2.67 in spraying technique compared 41.25±2.08 in dipping technique. While in L. spaericus recorded 62.08±3.41 mortality (%) in spraying technique but at dipping technique the mortality was 27.50±1.61. A sharp decrease was shown in number of stages resulting from lived treated females of T. urticae with P. aeruginosa by four concentrations 101, 103, 105 and 107 by using spraying technique and the life cycle was stopped at the larval stage only at concentration 101 and were not changed into the nymphal stage. While with dipping technique a slight increase in the average number of stages resulting from the adult living females treated with the previously aforementioned concentrations of bacteria P. aeruginosa. The present study cleared that application of bacteria strains on T. urticae adult females either by spraying or dipping techniques lead to some deformations such as, swelling of the body, then fluids exit followed by complete dryness of the body and forward protrusion of the podosoma region and finally death of the adult females
显示更多 [+] 显示较少 [-]Greenhouse and Laboratory Evaluation of The Efficiency of Green Silicon Dioxide Nanoparticles Against Tetranychus urticae (Koch)
2021
Heba Emam | Manal Ibrahim | Mervat Ibrahim | Salwa El-Sayed
Nanotechnology takes a significant position in controlling pests. Silicon dioxide nanoparticles (SiO2-NPs) is considered one of the best alter-natives to chemical pesticides for plant crop protection from harmful arthro-pods such as phytophagous mites, Tetranychus urticae. Therefore, this study aims to evaluate the effect of (SiO2-NPs) to control T. urticae. Under green-house conditions, the results revealed, in the larval stage, a high mortality percentage (99.05±0.83%) followed by eggs (98.74±1.22%). Besides, the nymph stage recorded high mortality (94.66±1.81%) at a high concentration of 1500 ppm. While the adult females of T. urticae recorded mortality of 91.92±1.02% after 72h. Eventually, the immature stages of T. urticae were susceptible to (SiO2-NPs). Meanwhile, at laboratory evaluation on immature stages of T. urticae which resulted from live treated females during 96h showed a sharp decrease in average numbers of eggs through 96h, at 1000 and 1500 ppm. No numbers of the larval stage were recorded at 1500 ppm. No number of nymph stage were recorded at all concentrations and periods. Moreover, activity of AChE was significantly inhibited at 1500 ppm, while activity of glutathione-S-transferase was significantly increased after 72 h. Finally, (SiO2-NPs) are effective against immature stages of T. urticae under greenhouse and laboratory conditions.
显示更多 [+] 显示较少 [-]BIOLOGICAL CONTROL OF SOIL -BORNE FUNGAL PATHOGENS
2019
Magdy Madkour | M. Afifi | E. Metry | I. Ismail
Seventeen bacterial isolates have been successfully isolated and purified from soil rhizosphere samples collected from different agricultural areas Buhayra, Sharqia and Alqilyubia of Egypt, and screened for production of chitinase enzymes had the highest chitinolytic activities amongst those investigated. Isolate S3-C and S1-C were Identified by biochemical, physiological tests and 16s rRNA gene primer as Bacillus cereus S3C, Gene Bank NCBI accession MK185696 and Bacillus cereus S1C accession MK185697. The production of chitinase by B.cereus S3C and Bacillus cereus S1C was optimized using colloidal chitin medium amended with 1% colloidal chitin at 30°C after five days of incubation. B.cereus S3C had potential for cell wall lysis of many phytopathogenic fungi tested such as Fusarium oxysporum and Rhizoctonia solani Potato phytopathogenic fungi by in vitro antagonistic test. The addition of B. cereus S3C chitinase was more effective than that of B.cereus S1C in increasing the resistance of Potato plants infected with various Soil- borne phytopathogenic fungi.
显示更多 [+] 显示较少 [-]THE SEASONAL ABUNDANCE OF SUNN PEST EGG PARASITOIDS Eurygaster integriceps Put. IN THE NORTH EAST OF SYRIA
2018
S. Sheikhmoos | M. Nehal | M. Al-Sltil | Randa Tara
The study of distribution and field efficacy of egg parasitoids was conducted in several wheat fields in north east of Syria (Amoda, Al-Qamishly, Al- Qehtanya, Al-Jwadya and Al-Malikya) in the 2011 field season. The results of surveys and taxonomy showed that fives parasitoid species belonging to Scelionidae family and order of Hymenoptera are: Trissolcus grandis Thomson, Trissolcus simoni Mayr, Trissolcus semistriatus Ness, Trissolcus vassiilievi Mayr and Gryon fasciatus Priener. The abundant species were T. grand which occurred in all sites and rate parasitism reached to 37.74% to all eggs, and T. vassilievi which occurred in all sites except Amoda and parasitism reached to 32.10%. T. semistriatus recovered in Al-Qamishly, Al- Qehtanya and Al-Malikya and parasitism reached to 16.98%. T. simoni was recovered only from Amoda, Gryon faciatus only from Al-Malikya. Overall parasitism rates reached 44.17% throughout the season.
显示更多 [+] 显示较少 [-]BIOLOGICAL CONTROL OF LASIODIPLODIA ROT OF MANGO FRUITS BY YEASTS
2014
S.T. Shehata
Ninety nine yeast isolates were isolated from surface of mango fruits and were tested in vivo in preliminary study for biocontrol potential of Lasiodiplodia rot of mango fruits. According to primary screening, nine isolates were selected to continue the secondary screening using different concentrations of the washed yeast cells in water suspension to study their biocontrol efficacy at 16±1°C. It was found that using washed cells of yeast isolate Mg 147 (Candida multisgemmis) at 1x109, 5x108 and 2x108 CFU/ml produced complete protection for 14 days to wounds of mango fruit inoculated with spore suspension of the fungusLasiodiplodia theobromae 1x105 conidia/ml. Meantime, no lesion developed on the mango fruit treated with the isolates Mg 39 (Pichia guilliermondii strainA) at the highest tested colony forming unit (CFU) levels, i.e. 1x109 and 5x108 CFU/ml. Supernatant of the yeast cultures, tested in secondary screening, did not prevent spore germination of L. theobromae or decay of wounded mango fruit but had inhibitory effect. However, 1-Methylcyclopropene (1-MCP) treatment significantly reduced the infected area mm2 on mango fruit inoculated with L. theobromae (1x105 conidia/ml) during the 14 days of storage at 16±1°C and improved efficacy of isolates Mg147 and Mg39. When applied as combined treatments between 1-MCP and biocontrol agents, no lesion developed on the fruit treated with the isolate Mg 147 at 1x 108 CFU/ml or higher. Meanwhile, no lesion developed on the fruit treated with the isolate Mg 39 at 2x 108 CFU/ml or higher while, the percentages of rot reduction were ranged between 94.1% - 81.3% for concentrations 1x108 and 6.6x107 CFU/ml respectively.
显示更多 [+] 显示较少 [-]BIOLOGICAL CONTROL OF TICKS IN SMALL SCALE DAIRY FARMS IN THE SUDAN
2008
Hassabo A A
Twenty dairy cows belonged to four small holder were put under study, to investigate the efficiency of using scavenger chicken (baladi) as biological control of ticks and their borne diseases. The cows were divided to two groups first and second, they were infested with ticks, Laboratory diagnosis for babesia was carried out. All samples showed positive reaction.Cloxon 2.5 gm/kg/ body weight (BW) was used to treat the cows of the two groups with the presence of ticks, and all cases were recovered. Gamatox was used to control the ticks on the cows in the first group, while scavenger chicken (5 baladi chicken in each farm), were used to control ticks in the second two farms. After seven days no tick was observed on the cows in the second group. It also showed negative result for babesia test. On the other hand, nymphs were noticed on the cows of the first group. The research recom-mended to use scavenger chicken to terminate the life cycle of ticks and to get rid of its pathogenic diseases in small scale dairy farms.
显示更多 [+] 显示较少 [-]ACTIVITY OF PEACH TWIG BORER Anarsia lineatella Zeller AND ITS ASSOCIATED BIO AGENTS ON PEACH TREES
2006
Salwa S.M. Abdel-Samad
The seasonal activity of the peach twig borer, Anarsia lineatella Zeller was in-vestigated during 2004 and 2005 seasons. The data revealed that the infested twigs empty from larvae (15%) were higher than that with larvae (1.25%) in February. The situation was reverse in April which recorded 8% and 14.75% for both, respec-tively. In fruits, infestation began to appear in the third week of March which rec-orded 2% whereas the maximum rate was recorded in May (16.75%). Three species of hymenopterous parasitoids were found; Apanteles ruficrus Haliday (Fam. Braco-nidae), Diplazon laetatorus Fab. (Fam. Ichneumonidae) and Microgaster tiro Rein-hard (Fam. Braconidae). These parasitoids reached its maximum during April (13.5%) that seems to be more active. Their numbers were positively correlated with the rate of infestation (r = + 0.799). In spite of presence of four predatory species (Coccinella undecimpunctata L., Rodalia cardinalis Mulsant, and Scymnus syriacus Marseul (Coleoptera: Coccinellidae) and Syrphus sp. (Diptera: Syrphidae)), it seems to be less active. Their numbers recorded very slight positive correlation with the rate of infestation (r =+0.423)
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