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PHYSIOLOGICAL RESPONSE OF STRAWBERRY GROWN IN ROOT- KNOT NEMATODE INFESTED SOIL UNDER DIFFERENT SAFETY CONTROL APPLICATIONS Texte intégral
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
Afficher plus [+] Moins [-]EFFECT OF NEEM AND WILLOW AQUEOUS EXTRACTS ON FUSARIUM WILT DISEASE IN TOMATO SEEDLINGS: 1-INDUCTION OF ANTIOXIDANT DEFENSIVE ENZYMES Texte intégral
2011
, R.M Farag Hanaa | Abdou Zeinab A. | Salama Dawlat A. | Ibrahim Mervat A.R. | Sror H.A.M.
Fusarium wilt disease is one of the major plant diseases that affect tomato production. The effects of neem (Azadirachta indica) and willow (Salix babylonica) aqueous extracts on fusarium wilt disease in tomato seedlings were investigated. Four weeks old tomato seedlings were treated with 10% of either neem and willow aqueous extracts and then infected with Fusarium oxysporum after 4 days of treatment. The results showed that the percentage of disease incidence was increased in non treated tomato seedlings in time dependent manner and reached the maximum level (65%) after 6 weeks of infection. Treatments of tomato plants with neem and willow aqueous extracts reduced the percentage of disease incidence to the level of 25.5% and 27.8% after 6 weeks of infection respectively. The results show that infection of tomato seedling with Fusarium oxysporum led to many morphological and biochemical changes including, reducing the growth of tomato shoot and root, increasing the level of lipid peroxidation and marked increase in the activities of antioxidant defensive enzyme i.e. POX, CAT, and SOD. Treatment with neem and willow aqueous extracts significantly exhibited a growth promotion of tomato shoot and root in infected or non infected seedling. Moreover, application of neem and willow aqueous extracts with fusarium, significantly reduce the level of lipid peroxidation and induce high activities of antioxidant defensive enzymes after 3 and 7 days of infection. Electrophoretic pattern of POX demonstrated that Fusarium oxysporum caused up regulation of several POX isoenzymes. It could be concluded that neem and willow aqueous extracts reduced the disease incidence of fusarium wilt in tomato seedlings by increasing the activities of antioxidant defensive enzymes and decreasing the level of lipid peroxidation.
Afficher plus [+] Moins [-]MICROBIAL PRODUCTION OF THERMOALKALIPHILIC ENZYMES FROM EL-KHORMA GOVERNORATE FOR APPLICATION IN BIODETERGENT TECHNOLOGY Texte intégral
2011
Detergents are an undetectable source of pollution, which hidden in most of our daily activities. Detergents could cause harmful effects before they are completely degraded. It is wise to reduce the amount of detergents that usually used by invention new bio-friendly formula contains efficient enzymes such as protease. Screening studies were carried out for one hundred and fifty bacterial isolates with respect to their ability to produce protease(s), after growing on slaughter house wastes (SHW) isolated from El-Khorma governorate,Taif, Kingdom of Saudi Arabia (KSA) at 55ºC, and pH 9. The most potent thermophilic bacterial isolate concerning of alkaline thermostable protease(s) production was identified as Bacillus licheniformis EGT50. Alkaline thermostable proteases productivity by the most potent bacterial isolate was affected by substrate concentrations (solid substrate), carbon source, nitrogen source, amino acid supplements, incubation temperature, incubation period, and inoculum size. Maximum both enzymes production by B. licheniformis EGT50 was obtained on SHW concentrations, 7.5 %; galactose; diammonium hydrogen phosphate; arginine at 55°C for 72 h. when inoculated by 0.5 ml. The protease production under all optimal conditions was increased many folds from 563.68 to 17825 U/ml (31 fold). The purification fold of B. licheniformis EGT50 alkaline thermostable protease increased to 394.7 after applying Sephadex G200 column chromatography techniques. The enzyme productivity of protease has been determined and the result proved the possibility to use the crude and purified enzymes in biodetergent technology
Afficher plus [+] Moins [-]ANTI-TUMOR ACTIVITIES AND OIL CONSTITUENTS OF ZINGIBER OFFICINALE (ZINGIBERACEAE Texte intégral
2011
El-Swaify Zeinab A. | Abd AL-Kawy Aisha M.
The phytochemical studies on Zingiber officinale rhizomes revealed that it contains traces of flavonoid, carbohydrates, tannins, steroles or terpenoids and it is free from alkaloids.Assay of essential oil of Zingiber officinale rhizome was also carried out. The alcoholic extract of the plant rhizome, was examined against five tumor cell lines, BHK-2, HEPG-2, MCF-7, HCT-2 and HEP-2, using SRB. assay. All cell lines were growth inhibited in a dose dependent manner after exposure to the plant extract. The antitumor activity of the plant extract using E.A.C. method, showed a high activity against mice tumor.
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