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141.
The herbicidal potential of culture filtrates of four Trichoderma spp., namely Trichoderma harzianum Rifai, Trichoderma pseudokoningii Rifai, Trichoderma reesei Simmons and Trichoderma viride Pers., was evaluated against two problematic weeds of wheat, Phalaris minor L. and Rumex dentatus L. In laboratory bioassays, generally, metabolites of all four Trichoderma species significantly reduced various root and shoot growth parameters of the two target weed species. The original concentrations of the culture filtrates of all Trichoderma spp., except T. harzianum, significantly reduced various parameters of root and shoot growth of wheat seedlings. In a foliar spray bioassay, the culture filtrates of all four Trichoderma spp. significantly diminished root and shoot biomass of R. dentatus. The effect of these filtrates on the shoot growth of P. minor and wheat was not significant. Culture filtrates of the four Trichoderma species were successively extracted with butanol, n-hexane, chloroform and ethyl acetate. In detached leaf injection bioassays, n-hexane fractions (3 mg mL(-1)) of T. pseudokoningii, T. reesei and T. viride, and ethyl acetate fractions of T. horzianum and T. pseudokoningii were found to be toxic against R. dentatus. This study concludes that the culture filtrates of Trichoderma species have herbicidal potential in the control of R. dentatus. 相似文献
142.
Khalafi L Rafiee M Sedaghat S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,81(1):661-665
The kinetic of the nitrous acid reactions with quercetin and catechin has been studied using spectrophotometric method in aqueous solution. The results show that these antioxidants participate in oxidation reactions with nitrous acid which is derived from protonation of nitrite ion in mild acidic conditions. Corresponding o-quinones as relatively stable products were detected by spectrophotometric techniques. pH dependence of the reactions has been examined and the rate constants of reactions were obtained by non-linear fitting of kinetic profiles. The effect of β-cyclodextrin on the oxidation pathway was another object of this study. It is shown that β-cyclodextrin has an inhibitory effect on the oxidation reaction. The rate constants of oxidation reactions for complexed forms and their stability constants were obtained based on changes in the reaction rates as a function of β-cyclodextrin concentration. 相似文献
143.
Ahmad Shaabani Afshin Sarvary Sajjad Keshipour Ali Hossein Rezayan Rahim Ghadari 《Tetrahedron》2010,66(10):1911-1914
A new class of pyridinium, quinolinium, isoquinolinum, and N-methylimidazolium-3-(2,5-dihydro-5-oxofuran-3-yl)-4-hydroxyfuran-2(5H)-one salts have been prepared in high yields by reacting pyridine, quinoline, isoquinoline, N-methylimidazole, 1,4-diazabicyclo[2.2.2]octane, and their derivatives with tetronic acid in CH2Cl2. 相似文献
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Nonlinear Dynamics - In this article, we consider a predator–prey system with constant rate of harvesting, which exhibits Hopf and Bogdanov–Takens bifurcations under certain parametric... 相似文献
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Keshavarz Mohammad Hossein Abadi Yasin Hayat Esmaeilpour Karim Damiri Sajjad Oftadeh Mohsen 《Chemistry of Heterocyclic Compounds》2017,53(6-7):797-801
Chemistry of Heterocyclic Compounds - This work uses density functional theory and suitable predictive methods to assess the effect of N-oxide group in 1,2-bis(6-nitro-1,2,4,5-tetrazin-3-yl)diazene... 相似文献
150.