خيارات البحث
النتائج 1 - 4 من 4
EVALUATING EFFECT OF PEPPER MINT OIL (Mentha pipreta) AND ITS NANO-FORMULATIONS ON SOME ENZYMATIC ACTIVITIES AND BIONOMICS OF COTTON LEAF WORM Spodoptera littoralis (BOISD.) [
2018
Dalia A. Yousef | A.E. Bayoumi | Nadia Z. Dimetry | A.H. Amin | E.M. Hoballah
Different formulations of pepper mint oil, i.e. bulk, nano-emulsion and nano-encapsulation were evaluated against 2nd and 4th instar larvae of the cotton leafworm Spodoptera littoralis (Boisd.). Their effects on enzymatic activities and bionomics were also investigated. Transmission Electron Microscopy (TEM) showed that the mean particle size of the prepared nano-emulsion ranged between 20-90nm. The encapsulation efficiency and loaded capacity percentages exhibited that distilled H2O was more suitable than ethanol in preparation of nano-encapsulation particles. Bioassay treatments showed LC50's on 2nd instars larvae were 70.59, 12.23 and 21.72 ppm for pepper mint oil, pepper mint nano-emulsion and loaded nanoemulsion, respectively. While on 4th instars these values were 80.47, 26.14 and 67.69 ppm, respectively. LC90's on 2nd instars were 104.75, 33.97 and 30.14 for pepper mint oil, pepper mint nanoemulsion and loaded nano-emulsion, respectively. While on 4th instars these values were 177.66, 71.37 and 102.29 ppm. Toxicity index and relative potency proved that nano-emulsion was more effective than loaded nano-emulsion, while the bulk preparation was the least effective one. Results of enzymatic activities showed marked effects of the three formulations of mint oil, significant inhibitions were recorded for amylase, invertase, trehalase, protease and alkaline phosphatase, while significant increase in activities of cuticle phenoloxidase and chitinase. Effects of adding the three formulations to artificial diet of 2nd instar showed significant effects of the insect bionomics. Larvae durations, percentage mortalities, were increased as well as larval malformations. Also, pupal duration, percentage pupal mortality and pupal malformation were increased, while pupal weight was decreased. Adults longevity showed insignificant effects, while female fecundity and egg % fertility showed significant responce.
اظهر المزيد [+] اقل [-]Wheat yield and antioxidant enzymes relationship under different soil water content
2010
Abdel-Kader, M.A. | Nour El-Din, N.A. | Fawzy, M.H. | Bechini, L.
The objectives of this study were to examine the relationship between wheat yield cultivars (Sakha 93 and Giza 168) and antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX) and phenylalanine ammonia-lyase (PAL) activities under different soil water content i.e. low, moderate and high content by Irrination at 806/6 ETo (1280m'/fed.), by, 100% ETo (1600m'/fed.) and120% ETo (1920m'/fed.), respectively. Two lysimeter experiments were carried out in two successive seasons i.e. 2006/2007 and 2007/2008 to estimate wheat yield and one experiment in plastic bags carried out of the greenhouse to determine the antioxidant enzymes of 28 days wheat plant under three different soil water content i.e. providIng wheat seedlings with aforementioned treatment. Exposing wheat cuitivars i.e. Giza 186 or Sakha 93 to water stress by Irrigation at 80% ETo (1280 m3/fad.) exerted an increase in CAT, SOD, POD, APX and PAL over those irrigated at 100% ETo (1600 m'/fad.) or at 120% ETo (1920 m'/fad.), but the previous enzyme activities in the tissue of Saka.93 surpassed of that of Giza 168 cuitivar. spike weight and weight of 100 grain/plant of Sakha 93 cuitivar overcome that of Giza 168 at low soil moisture content (80% ETo), whereas opposite results were obtained at high and moderate water content (120% and 100% ETo) in the first growing season (2006/2007) and spike weight/plant in second growing season (2007/2008). There was a proportional relationship between increasing soil moisture content and grain yield/plant but the difference between moderate water content 100% ETo (1600 m'/fed.) and high water content 120% ETo (1920 m3/fed.) was not significant. Providing 28 days wheat plant with low water content, decreased wheat yield/plant and its attributes comparing with moderate water content for the two studied cuitivars. The current study indicates that Sakha 93 cultivar was the most tolerant cuitivar compared with Giza 168.
اظهر المزيد [+] اقل [-]MOLLUSCICIDAL EFFICACY AND TOXICITY OF SOME PESTICIDES UNDER LABORATORY AND FIELD CONDITIONS
2006
Abdel-Halim K.Y. | A.A. Hussein | R.K. Abou-El Khear
Laboratory and field trials were carried out at Koom Hamada district and Etay El-baroud research station during 2004/ 2005 season to clarify the molluscicidal ac-tivities of the following: indoxacarb, lufenuron, Bacillus thurringiensis, kurestaci (Bt.) and methomyl against glassy clover snails Monacha cartusiana (Müler). Re-sults indicated that all tested pesticides decreased snails population compared with control. Under the field conditions, the efficiency of the tested compounds were 98.0, 93.4, 93 and 71.58% for methomyl, lufenuron, indoxacarb and Bt. after 5, 6, 13, and 28 days of treatment, respectively. Moreover the effect of LC50 and 0.5 LC50 of these compounds were investigated on some biochemical parameters in vivo. The activities of acetylcholinestrase (AChE), alanine aminotransferases (ALT) , as-partate aminotransferases (AST) and protein contents at different time intervals were evaluated. The specific activity of AChE reached 0.009, 0.002, 0.006 and 0.001 mole/ mg protein/ min for indoxacarb, lufenuron, Bt. and methomyl, respectively, after one day of treatment with (LC50 for each compound). In general, Bt. and in-doxacarb caused slight inhibition on AChE enzyme. All treatments decreased ALT and AST enzyme activity in the tested animals. However, Bt. Showed slight effect on the activity of aminotransferases enzymes.
اظهر المزيد [+] اقل [-]nzymes produced by some white-rot fungi on banana fruit stalk waste and its application
2001
Helmy, S.M. | Abdel-Nasser, N.H. (National Research Center, Cairo (Egypt). Microbial Chemistry Dept.)