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Journal of Plant Diseases and Protection - Citrus tatter leaf virus (CTLV), a strain of apple stem grooving virus, is a virus of citrus that is of commercial importance for trifoliate orange...  相似文献   
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The flame retardant behavior of cotton fabric treated with phosphorus-nitrogen containing triazine compound was evaluated. It was found that cyanuric chloride (2,4,6-trichloro-1,3,5-triazine) is an excellent starting material for the preparation of phosphonate flame retardants that interact well with cotton to improve flame resistance (FR) performance. Tetraethyl 6-chloro-1,3,5-triazine-2,4-diyldiphosphonate (TECTDP) has been prepared by a simple one-step reaction in high yield (98.0 %). Cotton fabrics treated with TECTDP result in covalent bond formation between TECTDP and hydroxyl groups in cotton fabrics. This FR system provides an efficient flame retardant for cotton textiles at low cost to meet government mandates. In this study, the FR material was synthesized and characterized by 1H and 13C nuclear magnetic resonance (NMR), and LC-MS spectroscopy. The chemical structure of cotton twill fabric treated with TECTDP by pad-dry-cure method was analyzed by FT-MIR and SEM. Furthermore, the thermal and flammability properties were evaluated by thermogravimetric analysis (TGA), limiting oxygen index (LOI, ASTM D-2863-09), and a vertical flame test (ASTM D-6413-08).  相似文献   
3.
Species/variety mixtures of Salix are used as a disease control strategy for rust (Melampsora epitea Thum. var. epitea) in short rotation coppice (SRC). Six LET (larici-epitea typica) pathotypes and two LR (larici-retusae) pathotypes of M. epitea var. epitea and also M. caprearum were detected in Northern Ireland plantations in 1994 and 1995. Three of these, LET7, LET8 and NI5 were detected in plantations for the first time. The predominant pathotype on most varieties was LET1. Logistic analysis showed that this pathotype was less prevalent on Salix X dasyclados Wimm. and more prevalent on S. viminalis L. 'Bowles Hybrid' than on S. viminalis '683'. The Shannon-Weaver Index of diversity indicated that there was greater pathotype diversity in mixtures than on the constituent varieties in monoculture. There was also a general trend of increasing diversity as the season progressed. The lowest pathotype diversity was recorded on S. viminalis 'Bowles Hybrid'. Pathotype predominance and diversity have an impact on the sustainability of the crop.  相似文献   
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While a large-scale soil amendment of biochars continues to receive interest for enhancing crop yields and to remediate contaminated sites, systematic study is lacking in how biochar properties translate into purported functions such as heavy metal sequestration. In this study, cottonseed hulls were pyrolyzed at five temperatures (200, 350, 500, 650, and 800 °C) and characterized for the yield, moisture, ash, volatile matter, and fixed carbon contents, elemental composition (CHNSO), BET surface area, pH, pHpzc, and by ATR-FTIR. The characterization results were compared with the literature values for additional source materials: grass, wood, pine needle, and broiler litter-derived biochars with and without post-treatments. At respective pyrolysis temperatures, cottonseed hull chars had ash content in between grass and wood chars, and significantly lower BET surface area in comparison to other plant source materials considered. The N:C ratio reached a maximum between 300 and 400 °C for all biomass sources considered, while the following trend in N:C ratio was maintained at each pyrolysis temperature: wood?cottonseed hull≈grass≈pine needle?broiler litter. To examine how biochar properties translate into its function as a heavy metal (NiII, CuII, PbII, and CdII) sorbent, a soil amendment study was conducted for acidic sandy loam Norfolk soil previously shown to have low heavy metal retention capacity. The results suggest that the properties attributable to the surface functional groups of biochars (volatile matter and oxygen contents and pHpzc) control the heavy metal sequestration ability in Norfolk soil, and biochar selection for soil amendment must be made case-by-case based on the biochar characteristics, soil property, and the target function.  相似文献   
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Although scores of experiments have examined the ecological consequences of transgenic Bacillus thuringiensis (Bt) crops, debates continue regarding the nontarget impacts of this technology. Quantitative reviews of existing studies are crucial for better gauging risks and improving future risk assessments. To encourage evidence-based risk analyses, we constructed a searchable database for nontarget effects of Bt crops. A meta-analysis of 42 field experiments indicates that nontarget invertebrates are generally more abundant in Bt cotton and Bt maize fields than in nontransgenic fields managed with insecticides. However, in comparison with insecticide-free control fields, certain nontarget taxa are less abundant in Bt fields.  相似文献   
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