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1.
A 2-year study was conducted to evaluate the relationship of plant yield responses to artificial infestations of the false
chinch bug (FCB)Nysius raphanus (Howard) on spring canola in Colorado, USA. Yield losses were greater when infestation occurred at the early flowering stage
(EFS) than at the early pod stage (EPS), in both 2001 and 2002. In the first trial in 2001, with infestations of 10, 20 and
40 FCB/head, the respective average yield losses over all cultivars were 43%, 68% and 69%, respectively, compared with the
non-infested control at the EFS, but 11%, 26% and 23% at the EPS. In the second trial in 2001, with infestations of 10, 20
and 40 FCB/head, the respective average yield losses over all cultivars were 26%, 58% and 55% at the early EFS, but 35%, 20%
and 35% at the EPS. Yield reductions from FCB infestation were lower in 2002 than in 2001. In the first trial in 2002, with
infestations of 10, 20 and 40 FCB/head, the respective average yield losses of all cultivars combined were 31%, 51% and 68%
at the EFS, and 13%, 32% and 18% at the EPS. However, in the second trial in 2002, with the same numbers of FCB per head,
no yield reductions were observed at either EFS or EPS. The number of FCB causing 10% yield loss in the four trials ranged
from 6.1 to 39.4 FCB/head (avg. 14.8) following infestation at the EFS and 15.4–109.8 (avg. 41.8) following infestation at
the EPS. Cultivar responses to FCB may also influence FCB yield reductions. However, in these studies all eight tested cultivars
sustained yield loss in at least one trial at some FCB infestation level. Variation between trials was substantial but a significant
level of resistance to FCB injury did not occur among the tested cultivars.
http://www.phytoparasitica.org posting Sept. 18, 2006. 相似文献
2.
Two trials were conducted in 2002 with 14-day-old spring canola (Brassica napus L.) seedlings to evaluate the effects of previous leaf injuries of different cultivars on subsequent injury by western black
flea beetle (WBFB),Phyllotreta pusilla Horn (Coleoptera: Chrysomelidae), under greenhouse conditions in Colorado (USA). Previous leaf cutting was found to have
only minor effects on subsequent infestation and injury by WBFB, and such effects may be cultivar-specific. Only IMC205 showed
significant differences by more than one parameter during these studies; cultivars Excel and 46A65 showed no responses in
injury or infestation between previously cut and uncut plants.
http://www.phytoparasitica.org posting Nov. 14, 2005. 相似文献
3.
Genotype,production system and sex effects on fatty acid composition of meat from goat kids 
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下载免费PDF全文 Mustafa Özcan Gulcan Demirel Akın Yakan Bülent Ekiz Cemil Tölü Türker Savaş 《Animal Science Journal》2015,86(2):200-206
Two trials were performed to assess the meat fatty acid profile of goat kids from different genotypes, production systems and sex. In the first trial, genotype effect was determined in 24 suckling male kids from Turkish Saanen, Maltese and Gokceada breeds. In the second trial, male and female Gokceada Goat kids were used to compare the effect of extensive and semi‐intensive production systems on fatty acid composition of meat. Significant genotype effect was observed in the percentages of myristic acid (C14:0), palmitic acid (C16:0), oleic acid (C18:1 n‐9), linolenic acid (C18:3 n‐3), arachidonic acid (C20:4 n‐6) and docosahexaenoic acid (C22:6 n‐3), despite no differences on the ratios of polyunsaturated fatty acids to saturated fatty acids (PUFA/SFA) and n‐6/n‐3 (P > 0.05). The effect of production system had also significant effects on fatty acids, but sex only influenced significantly stearic acid (C18:0), C18:1 n‐9 and C18:3 n‐3 fatty acids and total PUFA level and PUFA/SFA ratio. This study confirms that dairy breeds are prone to produce higher levels of unsaturated fatty acids in their muscle. Meanwhile, meat from Gokceada goat kids, which is one of the indigenous breeds in Turkey, had similar PUFA/SFA and n‐6/n‐3 ratios to Turkish Saanen and Maltase. 相似文献
4.
B. Cenkkut Gültekin Nergis Demirel Gültekin Onur Atak Ramazan Şimşek 《Fibers and Polymers》2018,19(2):313-320
Electromagnetic shielding has a very emerging role in the textile applications. Screen-printing is a well-known, easy and cost effective process for textile printing. In this study, carbon black and graphite particles were used to impart electromagnetic shielding property to polyester fabric by screen printing technique. To this aim, printing pastes containing carbon materials were prepared with different binder concentrations. The electrical resistance, surface morphology, color coordinates and washing fastness properties of screen printed polyester fabrics were investigated. The washing durability of electromagnetic shielding effectiveness of carbon based printed fabrics as a function of binder concentration have also been studied. Electromagnetic shielding effectiveness was evaluated in the frequency ranges between 15-3000 MHz. The results showed that the electromagnetic shielding properties of fabric were affected by increased binder concentration. The most durable electromagnetic shielding effectiveness after washing process was obtained at highest binder concentration. The surface morphologies and color difference values of printed fabrics after washing process also provided a positive contribution. 相似文献
5.
The appropriateness of three official fisheries management reference points used in the north‐east Atlantic was investigated: (i) the smallest stock size that is still within safe biological limits (SSBpa), (ii) the maximum sustainable rate of exploitation (Fmsy) and (iii) the age at first capture. As for (i), in 45% of the examined stocks, the official value for SSBpa was below the consensus estimates determined from three different methods. With respect to (ii), the official estimates of Fmsy exceeded natural mortality M in 76% of the stocks, although M is widely regarded as natural upper limit for Fmsy. And regarding (iii), the age at first capture was below the age at maturity in 74% of the stocks. No official estimates of the stock size (SSBmsy) that can produce the maximum sustainable yield (MSY) are available for the north‐east Atlantic. An analysis of stocks from other areas confirmed that twice SSBpa provides a reasonable preliminary estimate. Comparing stock sizes in 2013 against this proxy showed that 88% were below the level that can produce MSY. Also, 52% of the stocks were outside of safe biological limits, and 12% were severely depleted. Fishing mortality in 2013 exceeded natural mortality in 73% of the stocks, including those that were severely depleted. These results point to the urgent need to re‐assess fisheries reference points in the north‐east Atlantic and to implement the regulations of the new European Common Fisheries Policy regarding sustainable fishing pressure, healthy stock sizes and adult age/size at first capture. 相似文献
6.
The false chinch bug (FCB),Nysius raphanus (Howard) (Hemiptera: Lygaeidae), is one of the most significant pests on Brassicaceae plants. Different colored traps and
cups with plant extracts were tested to study attraction to FCB and its tachinid parasitoid,Phasia occidentis (Walker) (Diptera: Tachinidae). The yellow trap was the most attractive color to FCB, and the blue trap was the second. The
blue trap was also the most attractive color to the tachinid parasitoid of FCB. Both species also showed attraction to crude
extracts of canola and mustard oilseed. 相似文献
7.
A 3-year study was conducted in Colorado (USA) to evaluate the response of the western black flea beetle (WBFB),Phyllotreta pusilla Horn (Coleoptera: Chrysomelidae), to different colored mulches and to determine if there were diurnal differences in the
effect of mulch on their colonization on plants. The plants surrounded by aluminum mulch had the highest number of WBFB compared
with the rest of the treatments in 1999 and 2000, but not in 2002; the black mulch had the lowest number of WBFB in 3 years
of sampling. The highest number of WBFB were observed in the late day (4 p.m.) counting in 1999, whereas none of the treatments
resulted in significant differences among early, mid, and late day counts in 2000 and in 2002.
http://www.phytoparasitica.org posting May 20, 2005. 相似文献
8.
Feza Can Nihat Demirel Erkan Isa Sağıroğlu Teodora Toshova Mitko Subchev 《Phytoparasitica》2010,38(3):217-222
The vine bud moth, Theresimima ampellophaga (Bayle-Barelle 1808) (Lepidoptera: Zygaenidae; Procridinae), is a pest on grape vine, Vitis vinifera (L.), and on the ornamental vine Parthenocissus quinquefolia (L.) and other Parthenocissus species. Its recent distribution in Europe is relatively well known, but there is a paucity of locality data for Turkey. As a consequence, we began a large-scale investigation into its distribution and seasonal activity in this country in 2008. The main tools for these investigations were pheromone traps that were baited with the synthetic pheromone of the species, viz. (2R)-butyl (Z7)-tetradecenoate. As a result of field work carried out in the eastern Mediterranean region of Turkey in 2008 and 2009, Th. ampellophaga was recorded in five provinces, viz. Adana, Mersin, Hatay, Kahramanmara? and Kilis. The only province where the pest was not found was Gaziantep. Theresimima ampellophaga produces one or two generations per year, depending on the local conditions and other unknown factors. The moths of the first generation fly in June, while those of the second generation occur in August. To the best of our knowledge the present paper provides the first well-documented evidence of the occurrence of a second generation of the vine bud moth in Turkey. 相似文献
9.
Rainer Froese Nazli Demirel Gianpaolo Coro Kristin M Kleisner Henning Winker 《Fish and Fisheries》2017,18(3):506-526
This study presents a Monte Carlo method (CMSY) for estimating fisheries reference points from catch, resilience and qualitative stock status information on data‐limited stocks. It also presents a Bayesian state‐space implementation of the Schaefer production model (BSM), fitted to catch and biomass or catch‐per‐unit‐of‐effort (CPUE) data. Special emphasis was given to derive informative priors for productivity, unexploited stock size, catchability and biomass from population dynamics theory. Both models gave good predictions of the maximum intrinsic rate of population increase r, unexploited stock size k and maximum sustainable yield MSY when validated against simulated data with known parameter values. CMSY provided, in addition, reasonable predictions of relative biomass and exploitation rate. Both models were evaluated against 128 real stocks, where estimates of biomass were available from full stock assessments. BSM estimates of r, k and MSY were used as benchmarks for the respective CMSY estimates and were not significantly different in 76% of the stocks. A similar test against 28 data‐limited stocks, where CPUE instead of biomass was available, showed that BSM and CMSY estimates of r, k and MSY were not significantly different in 89% of the stocks. Both CMSY and BSM combine the production model with a simple stock–recruitment model, accounting for reduced recruitment at severely depleted stock sizes. 相似文献
10.
Although proline is one of the major computable organic solutes that accumulate in many plant species in abiotic stresses, a hot debate continues about whether proline accumulation is a reaction to abiotic stress, or a plant's response is associated with stress tolerance. The effects of proline on antioxidative system in grape leaves of Vitis vinifera L. cv., ‘Öküzgözü’ exposed to oxidative stress by H2O2 was investigated. Endogenous proline, hydrogen peroxide (H2O2), malondialdehyde (MDA) concentrations, percentage of electrolyte leakage (EL), and some of the antioxidant enzyme activities; such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and guaiacol peroxidase (POD) were measured spectrophotometrically. Inhibitory effect of H2O2 on antioxidant enzyme activities, MDA, and EL was found. In the presence of proline, SOD and CAT activities decreased, while POD and APX activities increased. Proline pre-treatment resulted in a decrease in cellular H2O2 content, MDA, and EL, while cellular concentration of proline increased. Based on the finding, it was suggested that proline and H2O2 could play an important role in oxidative stress injury of grapevine leaves grown in vitro culture. Also, proline might have a direct positive effect on antioxidant enzyme system, membrane phase change, MDA, and EL. 相似文献