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1.
Larvae of the lesser date moth (Batrachedra amydraula Meyr.) cause damage to dates in Iraq. A formulation based on a mixture of equal parts of wheat flour and pollen grains and containing either chlorpyrifos, fenitrothion or pirimiphos-methyl (all at 5 mg kg?l) was dusted (5 g formulation bunch?1) onto female clusters of dates at the time of pollination. Numbers of larvae, yield of dates and insecticide residues were monitored over a three-month period. Results showed that, by this technique, all three insecticides were effective in controlling the pest but that fenitrothion and chlorpyrifos were better than pirimiphos-methyl.  相似文献   
2.
Anthelmintic resistance in nematode parasites of sheep and goats on a government farm in north Malaysia was monitored over a 3-year period (1997–2000). The faecal egg count reduction test (FECRT) was conducted on young sheep at the beginning and end of this period. Changes in management, designed to reduce the selection pressure for the development of anthelmintic resistance, were also implemented during this time. By far the most important parasite problem was Haemonchus contortus. In 1997, this nematode was found to be resistant to levamisole, with suspected resistance to closantel and moxidectin. However, when the FECRT was repeated 3 years later, its resistance status had become much more severe, with resistance to benzimidazole, levamisole and ivermectin, and suspected resistance to moxidectin. This rapid evolution to multiple anthelmintic resistance is a major concern that needs to be arrested. There is an urgent need to evaluate other control strategies that incorporate livestock management, the `smart' use of drugs and non-chemotherapeutic approaches, such as biological control agents.  相似文献   
3.
Field applications usingBacillus thuringiensis (Dipel 2 X) againstSpodoptera exigua infesting corn and sunflower cultivations were carried out in two different localities in Egypt. The percentage of infested corn plants decreased to 2.5%, seven days after treatment with Dipel 2x, (250 g/fed) and the yield was significantly increased compared with untreated plots. The carbamate insecticide (Lannate) at 300 g/fed caused complete kill to the larvae and the highest yield was obtained. Application of Lannate, Dipel (250 g) or a combination of both (150 g/each/fed) caused a high reduction of the larvae existing in sunflower after seven days from application, while Dipel at 200 g/fed gave a lower effect. Ten days after application, the number of larvae and infested plants increased significantly in plots treated with Lannate alone, while plots treated with either Dipel (250 g) or Dipel combined with Lannate (150 g/each) still maintained a lower infestation. The estimated yield showed the highest increase in plots treated with Lannate followed by Dipel (250 g) and then a combination of both.  相似文献   
4.
The effective threshold rate of application of Dipel 2X was 250g/f. Incorporation of some chemical additives such as calcium sulphate (CaSO4) or calcium oxide (CaO) significantly potentiated the effectiveness of Dipel 2X on larval population. The addition of calcium carbonate (CaCO3) and zinc sulphate (ZnSO4) to Dipel 2X greatly reduced the larval population and led to a significant increase in the yield of some vegetable crops. Dipel 2X baits at 250g/f were almost as effective as the chemical insecticide Hostathion when used at 1.5l/f in controllingA. ypsilon larvae attacking vegetable crops. Control of the greasy cutwormAgrotis ypsilon population was better achieved when the biological control agent Dipel 2X was used as baits.  相似文献   
5.
The fatty acid, sn-2 fatty acid, triacyglycerol (TAG), tocopherol, and phytosterol compositions of kernel oils obtained from nine apricot varieties grown in the Malatya region of Turkey were determined ( P<0.05). The names of the apricot varieties were Alyanak (ALY), Cataloglu (CAT), C?loglu (COL), Hacihaliloglu (HAC), Hacikiz (HKI), Hasanbey (HSB), Kabaasi (KAB), Soganci (SOG), and Tokaloglu (TOK). The total oil contents of apricot kernels ranged from 40.23 to 53.19%. Oleic acid contributed 70.83% to the total fatty acids, followed by linoleic (21.96%), palmitic (4.92%), and stearic (1.21%) acids. The s n-2 position is mainly occupied with oleic acid (63.54%), linoleic acid (35.0%), and palmitic acid (0.96%). Eight TAG species were identified: LLL, OLL, PLL, OOL+POL, OOO+POO, and SOO (where P, palmitoyl; S, stearoyl; O, oleoyl; and L, linoleoyl), among which mainly OOO+POO contributed to 48.64% of the total, followed by OOL+POL at 32.63% and OLL at 14.33%. Four tocopherol and six phytosterol isomers were identified and quantified; among these, gamma-tocopherol (475.11 mg/kg of oil) and beta-sitosterol (273.67 mg/100 g of oil) were predominant. Principal component analysis (PCA) was applied to the data from lipid components of apricot kernel oil in order to explore the distribution of the apricot variety according to their kernel's lipid components. PCA separated some varieties including ALY, COL, KAB, CAT, SOG, and HSB in one group and varieties TOK, HAC, and HKI in another group based on their lipid components of apricot kernel oil. So, in the present study, PCA was found to be a powerful tool for classification of the samples.  相似文献   
6.
Pistachio (Pistacia vera L.) is a strategic nut tree species in the Middle East which holds comparative advantage over other fruit trees in view of its hardiness, income generation opportunities and benefits for the ecosystem. Yet pistachio cultivation depends on a very narrow genetic base, in spite of the existence of many varieties still marginally exploited. Syria is an important center of diversity for pistachio. A country wide ecogeographic survey in this country was carried out to determine the extent of pistachio genetic diversity and its use. As a whole, 114 accessions were collected from 37 farms to assess diversity at morphological and molecular level. Molecular evaluation was carried out using Amplified Fragment Length Polymorphism (AFLP) technique and performed using seven primer pair combinations. Results from the studies allowed the identification of 25 pistachio female varieties in Syria, some of which unique and described for the first time. Three groups of pistachio diversity were identified by cluster analysis which provides useful information about the distribution of genetic diversity in Syria for enhanced use and sustainable conservation.  相似文献   
7.
Milled wood and milled wood lignin (MWL) samples were subjected to DFRC and thioacidolysis. Despite the fact that both methods selectively cleave aryl ether bonds, substantial differences in results were obtained. Lignin thioacidolysis gave total molar yields of degradation monomer products in the range of 3.5-7 mol % higher than DFRC. GPC analysis showed that the thioacidolysis-treated lignin was degraded to a lower average molecular weight than that treated by DFRC. Contrary to results reported for lignin model compounds, these results indicate that the DFRC method does not completely or efficiently degrade the lignin polymer. In fact, the DFRC-degraded lignin retained much of the characteristics of the original MWL. Elemental analysis revealed the presence of bromine in the DFRC-treated lignin, and two-dimensional (1)H-(13)C HMQC NMR spectroscopy showed the presence of beta-O-4 linkages in the DFRC-treated lignin. No beta-O-4 interunit linkages were detected in the thioacidolysis-treated lignin. These results are consistent with the lower monomer yields and the higher average molecular weight of the DFRC-treated lignin and indicate inefficiency in the chemistry of the method, probably due to steric constraints of the polymeric nature of lignin.  相似文献   
8.
9.
Fusidic acid known to has antibacterial, antifungal, and antimalarial activities. Fusidic acid blocks translation elongation factor G gene in Plasmodium falciparum. In the present study, the inhibitory effects of fusidic acid on the in vitro growth of bovine and equine Babesia parasites were evaluated. The inhibitory effect of fusidic acid on the in vivo growth of Babesia microti was also assessed. The in vitro growth of four Babesia species that were tested was significantly inhibited (P < 0.05) by micromolar concentrations of fusidic acid (IC50 values = 144.8, 17.3, 33.3, and 56.25 μM for Babesia bovis, Babesia bigemina, Babesia caballi, and Theileria equi, respectively). Combinations of fusidic acid with diminazene aceturate synergistically potentiated its inhibitory effects in vitro on B. bovis and B. caballi. In B. microti-infected mice, fusidic acid caused significant (P < 0.05) inhibition of the growth of B. microti at the dose of 500 mg/kg BW relative to control group. These results indicate that fusidic acid might be incorporated in treatment of babesiosis.  相似文献   
10.
Plant production in potting substrates provides maximum profit on the applied inputs, and hence, directly improving the socio-economic condition of the grower/nurserymen. The main challenge in this industry is sourcing of materials for their potting substrates. Peat and perlite have been widely preferred materials. However, recently higher prices, more restrictive legislation of many countries and wetland ecosystem destruction through its extraction has limited peat use. Nowadays, producers focus towards peat alternatives that provide good performance, are readily available, inexpensive and environment friendly to attain sustainability in potted plant production. In an effort to grasp sustainability during the last few decades, many industrial and agricultural waste materials were reviewed for their use in potting substrates. In these studies, the major focus remained on material characterization, neglecting their economics, technical aspects and environmental impacts. Thus, switching from peat and perlite to alternatives requires material exploration. In the present review, we summarize a clearer and practical approach for substituting different materials especially biochar to fulfill the need of modern potting substrate industry. Biochar has the potential to sustain the substrate production on a long-term basis.  相似文献   
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