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91.
The aim of this study was to determine the efficacy of several alternative postharvest treatments to sulfur dioxide (SO2) in maintaining quality and reducing fungal decay during cold storage of ‘Red Globe’ table grapes. Grapes were packaged in perforated polyethylene (PPE) or modified atmosphere packaging (MAP) bags (ZOEpac or Antimicrobial) with or without different grades of ethanol vapor-generating sachets (Antimold®30, Antimold®60 or Antimold®80) or a SO2-generating pad, and the grapes were kept at 0 °C and 90-95% relative humidity for 4 months. Packaging of grapes with a SO2 pad in PPE or ZOEpac bags provided better control of fungal decay and stem browning than PPE or ZOEpac bags alone, PPE or ZOEpac bags with Antimold sachets or Antimicrobial bags alone. The PPE bag containing the Antimold®80 sachet was as effective as the SO2 treatments in reducing the incidence of fungal decay in naturally infected and artificially inoculated grapes for 1 month. Ethanol vapor released by the Antimold sachets enhanced berry color, but caused stem browning depending on ethanol vapor concentrations in the headspace of the bags. The ZOEpac-210 bags alone resulted in significantly lower weight loss and incidence of stem browning, compared to other treatments; however, they did not reduce fungal decay or develop an appreciable level of modified atmosphere.  相似文献   
92.
Disease incidence and severity was studied for winter wheat variety Bezostaya 1 and susceptible checks based on data from international nurseries from 1969 to 2010 and from 51 countries across major winter wheat production regions totalling 1,047 reports. The frequency of leaf rust and stripe rust occurrence was stable over time with marked increases in severity in 2001–2010 especially in Europe and Central and West Asia. Substantial global reductions in stem rust occurrence were recorded and attributed primarily to use of resistance genes although the recent emergence of race Ug99 makes wheat more vulnerable. The occurrence of powdery mildew remained globally stable over time. It was the most important foliar disease in Western and Southern Europe, where the frequency was very high for all time periods coupled with slight increases in severity during 2001–2010. The durable resistance of variety Bezostaya 1 to all four diseases was demonstrated in the study using comparisons of disease severities of Bezostaya 1 and the most susceptible entries. The Lr34/Yr18/Pm38 pleiotrophic set possessed by Bezostaya 1 is currently an important target for selection because it is now amenable to molecular selection. Increased use of genes like Lr34 combined with strategies to minimize cultivation of extremely susceptible varieties will contribute to long term maintenance of low and non-damaging disease levels. The durable disease resistance of Bezostaya 1, combined with its adaptability and good end-use quality, was a significant reason for its huge impact in agriculture over the last 50?years.  相似文献   
93.
94.
Kinesin is a processive motor that takes 8.3-nm center-of-mass steps along microtubules for each adenosine triphosphate hydrolyzed. Whether kinesin moves by a "hand-over-hand" or an "inchworm" model has been controversial. We have labeled a single head of the kinesin dimer with a Cy3 fluorophore and localized the position of the dye to within 2 nm before and after a step. We observed that single kinesin heads take steps of 17.3 +/- 3.3 nm. A kinetic analysis of the dwell times between steps shows that the 17-nm steps alternate with 0-nm steps. These results strongly support a hand-over-hand mechanism, and not an inchworm mechanism. In addition, our results suggest that kinesin is bound by both heads to the microtubule while it waits for adenosine triphosphate in between steps.  相似文献   
95.

The objective of this study was to evaluate several selected Cucurbita genotypes for their salt resistance in a rootstock breeding program for grafted watermelon seedling production. Specifically, changes in the relative water content (RWC), leaf area (LA), total chlorophyll content (TCC) and proline concentration (PC) of a commercial cultivar (G32 code), two promising winter squash (G12 and G13 of Cucurbita maxima Duch.) lines, six pumpkin (G3, G27, G28, G29, G30 and G31 of Cucurbita moschata Duch.) lines, and four C. maxima?×?C. mochata hybrids (G14, G15, G40 and G42), were investigated with a control treatment and four levels of salt stress (4, 8, 12 and 16?dS/m). In this study, Cucurbita cultivars which showed significant differences according to RWC, LA, TCC and PC at least significant difference (LSD) tests (P?<?0.05) and had salinity sensitivity index (SSI) value lower than 20%, were assessed as salt tolerant genotypes. The salt tolerant genotypes were grouped with principal component analysis (PCA) in each salt level. At the end of the study, all genotypes for all characteristics were generally tolerant at 4?dS/m salinity level. The G3, G12, G13, G14, G29 and G42 genotypes were resistant at 8?dS/m salinity, while the G15, G31, G32 and G40 were the most resistant genotypes at 12 and 16?dS/m. In conclusion, the selection of more salt resistant cultivars in rootstock breeding programs should be a priority to maintain growth performance in saline environments.

  相似文献   
96.
The essential oil isolated from Turkish tarragon (Artemisia dracunculus) by hydrodistillation was analyzed by GC-MS. Thirty compounds representing 99.5% of total oil were identified. The predominant components in the oil were (Z)-anethole (81.0%), (Z)-beta-ocimene (6.5%), (E)-beta-ocimene (3.1%), limonene (3.1%), and methyleugenol (1.8%). The antibacterial and antifungal activities of the essential oils isolated from A. dracunculus, Artemisia absinthium, Artemisia santonicum, and Artemisia spicigera oils were also evaluated. In general, the oils exhibited potent antifungal activity at a wide spectrum on the growth of agricultural pathogenic fungi. Among the oils, the weakest antifungal activity was shown by the oil of A. dracunculus. In many cases, the oils of A. absinthium, A. santonicum, and A. spicigera completely inhibited the growth of some fungal species. As compared with antibacterial activities of all of tested oils, A. santonicum and A. spicigera oils showed antibacterial activities over a very wide spectrum. However, the essential oils tested showed lower inhibition zones than the inhibition zones of penicillin. In addition, antioxidant and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities of tarragon oil were determined, and weak antioxidant and DPPH radical scavenging activities were found in comparison to butylated hydroxytoluene.  相似文献   
97.
The main objective of this investigation was to evaluate the response of red pepper grown in a subhumid climate to different irrigation and nitrogen levels. Open-field trials were conducted in the Marmara Region, Turkey. Plants were subjected to three water levels [full irrigation (FI) = 100% crop evapotranspiration (ETc) and two deficit irrigations (DIs)= 66 and 33% ETc restoration] and four levels of N (0, 80, 160, and 240 kg N ha?1) during the 2012, 2013, and 2014 growing seasons. A split-plot experimental design was used. The highest values of biomass and marketable yield (MY) were observed under FI. DI significantly increased the fruit soluble solids content. The biomass yield, MY, and fruit weight significantly improved with increasing nitrogen levels. The 240 kg N ha?1 treatment under FI provided the maximum net income. Increasing N supply under DI conditions enhanced the water-use efficiency based on both biomass yield and MY. These results indicate that with respect to the yield, the net income, and the water productivity of red pepper, the FI with a nitrogen supply of 160–240 kg ha?1 is recommended for drip irrigated and N-fertigated red pepper under subhumid climate conditions.  相似文献   
98.
Outdoor performances of a polyurethane varnish and an alkyd-based synthetic varnish coated over chromium-copper-boron (CCB)-impregnated Scots pine (Pinus sylvestris L.) and chestnut (Castanea sativa Mill.) [10 (R) × 100 (T) × 150 (L) mm] were investigated. These varnishes were also applied to the wood surface as sole coatings or impregnated into wood as water-repellent (WR) solutions. Outdoor exposure was performed in the Black Sea region of northern Turkey (41°N, 39.43°E) where humid weather predominates throughout the year and accelerates decomposition of coated wood surfaces. The wood panels were exposed at 45° south on their tangential surfaces. After 9 months of exposure to summer, autumn, and the following winter season, the color and glossiness changes of the exposed surface, adhesion of the coating layer to the wood surface, water absorption through the coating layers, mass loss, and the hardness of the board surface were studied. CCB impregnation greatly stabilized the surface color of varnish-coated panels of both wood species. Gradual decreases of adhesion between varnished layers and preimpregnated surfaces were attributed to probable weakening of interactions at the interface of the treated wood and the film layer. A superficial cleaning process of treated wood is suggested to improve glossiness and adhesion. The coated wood surface became harder with time on outdoor exposure until a maximum hardness occurred followed by softening, whereas the uncoated surface softened steadily. Polyurethane varnish yielded a harder surface than synthetic varnish. Mass losses of wood panels after 9 months of exposure were negligible for all treatments compared with the untreated controls, which were totally discolored and eroded on the surface. It is concluded that long-term exterior wood protection has been achieved by a successful combination of an appropriate preservative treatment followed by a compatible surface-coating process.  相似文献   
99.
100.
This study was conducted to determine the effects of the use of farmed salmon oil (FSO) as a substitute for anchovy oil (AO) on growth and nutrient utilization performance, and proximate and fatty acid compositions of turbot, Psetta maxima. Two fish oil sources, AO and FSO, were incorporated into the diet at a level of 6.77% and fed to turbot with an initial average weight of 266.25 ± 0.53 g in brackish water for 9 wks. Each diet was tested in four replicates and fed to apparent satiation twice a day. At the end of the experiment, data of growth and nutrient utilization performances (feed conversion ratio, nitrogen, lipid and energy intakes, gains, and retentions), and organo‐somatic indices were similar between the dietary oil sources. Likewise, there were no significant differences in final whole body proximate compositions between two treatments. However, AO and FSO diets significantly affected whole body fatty acids and fatty acids classes. Briefly, FSO fish was characterized with higher n‐6 poly unsaturated fatty acids (PUFA) mainly 18:2n‐6 whereas AO fish with higher n‐3 PUFA and highly unsaturated fatty acids mainly 22:6n‐3. The whole body fatty acid profile reflected that of the diets. It is concluded that incorporation of FSO instead of AO in turbot diets supports similar growth and nutrient utilization performances but change whole body fatty acid profile.  相似文献   
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