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61.
Despite recreational fisheries serving as a prime example of a coupled social–ecological system, much of the research on such fisheries has been monothematic in orientation and focused either on fisheries ecology or human dimensions. An attempt was made to break down some of the barriers to more interdisciplinary research on recreational fisheries at the 6th World Recreational Fishing Conference. The overall conclusion was that future research and management efforts should increasingly focus on the feedbacks between the interacting human and ecological components of recreational fisheries. Doing so promises to improve understanding of how recreational fisheries respond to social–ecological change. In this context, the behaviour of both fishes and humans provides an important, yet often overlooked, integrator of the ecological and social components of recreational fisheries. A better understanding of the behavioural dynamics of recreational fishers as well as exploited fishes will help predict how recreational fisheries change, evolve, adapt and reorganise through time to maintain resilience and achieve sustainability on a global scale. 相似文献
62.
Steven J Cooke Cory D Suski Robert Arlinghaus Andy J Danylchuk 《Fish and Fisheries》2013,14(4):439-457
Traditional regulatory options (formal institutions) imposed by government agencies such as harvest and gear restrictions represent the standard in recreational fisheries management, at least in developed countries. However, there exist a number of alternatives including the use of angler education programmes that attempt to evoke voluntary changes in angler behaviour, resulting in the emergence of voluntarily motivated resource‐conserving informal institutions. These ‘softer’ approaches to aquatic stewardship and fisheries management can be developed in cooperation with stakeholders and in many cases are led by avid anglers and angling groups. Examples of such measures include voluntary sanctuaries, informally enforced seasonal closures, personal daily bag limits, self‐imposed constraints on gear, development of entirely live‐release fisheries, and adoption of fish and aquatic ecosystem conservation‐oriented gears and release practices. Education efforts that provide anglers with knowledge on best practices and empower them to modify their behaviour hold great promise to meet formal management goals and objectives, but seem to be underutilized relative to formal regulations. This article highlights the benefits and challenges of relying on informal institutions as alternatives to traditional regulatory options. Informal institutions that protect resources and help overfished stocks recover hold great promise in both developed and developing countries, particularly when there is a single stakeholder group or when the capacity to enforce traditional regulations or to invest in stock assessments is limited. Informal institutions may help make formal institutions more effective or can even be alternatives to costly institutions that depend on enforcement to be effective. 相似文献
63.
Within-field variability of Fusarium head blight pathogens and their associated mycotoxins 总被引:1,自引:0,他引:1
X.-M. Xu D. W. Parry P. Nicholson M. A. Thomsett D. Simpson S. G. Edwards B. M. Cooke F. M. Doohan S. Monaghan A. Moretti G. Tocco G. Mule L. Hornok E. Béki J. Tatnell A. Ritieni 《European journal of plant pathology / European Foundation for Plant Pathology》2008,120(1):21-34
Within-field variability in the Fusarium head blight (FHB) and its associated mycotoxins was studied in four European countries.
At each of 14 sites, each FHB pathogen and associated mycotoxins were quantified in 16 quadrat samples at harvest. Overall,
the incidence of quadrat samples with detectable and quantifiable pathogen DNA was significantly lower in the grain than in
the corresponding chaff. Deoxynivalenol (DON) was the most frequently detected toxin in the samples and its accumulation was
most strongly associated with the presence of Fusarium graminearum. Nivalenol (NIV) accumulation was significantly associated only with the presence of F. culmorum. Zearalenone (ZON) accumulation was strongly associated with the presence of all three pathogens (F. graminearum, F. culmorum and F. poae). The levels of both DON and ZON concentrations were positively related to the amount of F. graminearum DNA in the grain or in the chaff. The presence/absence of FHB pathogens within a single quadrat appeared to be independent
of each other. The presence of a particular FHB pathogen and the amount of its DNA, as well as the associated mycotoxin(s),
varied greatly among samples at each site. This study demonstrated the large extent of within-field variability of FHB and
its associated mycotoxins, and the importance of representative sampling in FHB studies. 相似文献
64.
65.
66.
I.J. Cooke 《The Journal of Horticultural Science and Biotechnology》2013,88(3):285-292
The influence of far-red light on the development of tomato seedlings was investigated. It was found that a deficiency of it in the incident spectrum retarded stem elongation. The quantity of far-red light in the flux did not affect the number of flowers forming on the first truss or the time of anthesis. 相似文献
67.
Mehmet E. Göre Nedim Altın Kevin Myers David E. L. Cooke William E. Fry Göksel Özer 《Plant pathology》2021,70(4):898-911
Late blight, caused by the oomycete Phytophthora infestans, is considered the most important and destructive disease of potato in Turkey. In this study, characterization of 367 isolates of P. infestans obtained from the potato-growing areas of the country was carried out to evaluate the pathogen population structure over the 2017–2019 production seasons. The isolates were characterized by numerous features including mating type, in vitro mefenoxam sensitivity, simple-sequence repeat (SSR) markers, and virulence against a set of potato differential lines. Most isolates were A2 mating type (353 isolates). Also, 68% of isolates were resistant to mefenoxam; the remainder were intermediate in their sensitivity and there were no sensitive isolates. SSR-based genotypic analysis of P. infestans populations showed a low genetic diversity. The 13_A2 clonal lineage predominated with a frequency of 92.1%, followed by 34_A1 (3.3%) and 37_A2 (2.7%). Genotypes 34_A1 and 37_A2 were detected only in 2019. This is the first report of 34_A1 and 37_A2 clonal lineages causing late blight disease of potato in Turkey. The most abundant virulence type was one overcoming resistance genes R1, R2, R3, R4, R6, R7, R10, and R11. These results emphasized that the migration of individuals and the asexual generation of subclonal differences were the main factors driving the population structure of P. infestans in Turkey. 相似文献
68.
S. Nolan B.M. Cooke 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(2):203-207
A field study is described which explored the possibility of controlling Stagonospora nodorum and Septoria tritici on wheat using a barley pathogen, Drechslera teres. Pre-treatment of wheat cv. Hussar flag leaves with D. teres resulted in a significant reduction in disease caused by S. nodorum and S. tritici, resulting in a significant increase in grain yield. When cv. Brigadier leaves were treated with D. teres prior to inoculation with S. nodorum there was an initial increase in disease expression whilst D. teres had no effect on symptoms produced by S. tritici on cv. Brigadier. There was significantly less disease on leaves of cvs. Hussar and Brigadier pre-treated with D. teres prior to inoculation with an equal mixture of S. nodorum and S. tritici compared to plants pre-treated with water. It is concluded that D. teres and other non-host pathogens show potential as biological control agents for S. nodorum and S. tritici. 相似文献
69.
Evidence for selection pressure from resistant potato genotypes but not from fungicide application within a clonal Phytophthora infestans population 下载免费PDF全文
J. S. Stellingwerf S. Phelan F. M. Doohan V. Ortiz D. Griffin A. Bourke R. C. B. Hutten D. E. L. Cooke S. Kildea E. Mullins 《Plant pathology》2018,67(7):1528-1538
Insight into pathogen population dynamics provides a key input for effective disease management of the potato late blight pathogen Phytophthora infestans. Phytophthora infestans populations vary from genetically complex to more simple with a few clonal lineages. The presence or absence of certain strains of P. infestans may impact the efficacy of fungicides or host resistance. Current evidence indicates that genetically, the Irish populations of P. infestans are relatively simple with a few clonal lineages. In this study, P. infestans populations were genetically characterized based on samples collected at the national centre for potato breeding during the period 2012–16. The dominance of clonal lineages within this P. infestans population was confirmed and the potential selection pressure of fungicide treatment (2013–15) and host resistance (2016) on this clonal P. infestans population was then investigated. It was found that fungicide products did not notably affect the genetic structure of sampled populations relative to samples from untreated control plants. In contrast, samples taken from several resistant potato genotypes were found to be more often of the EU_13_A2 lineage than those taken from control King Edward plants or potato genotypes with low resistance ratings. Resistant potato varieties Sarpo Mira and Bionica, containing characterized R genes, were found to strongly select for EU_13_A2 strains. 相似文献
70.
Vermunt JJ West DM Cooke MM Alley MR Collins-Emerson J 《New Zealand veterinary journal》1994,42(4):133-136
Sickness and deaths associated with leptospirosis were reported in three lamb flocks in the Manawatu region. The clinical, pathological and serological features of Leptospiru interrogans serovar pomona infection are described. The mucous membranes of affected animals were pale and jaundiced. Haemoglobinuria, haemoglobinaemia and centrilobular hepatocellular necrosis were also consistent findings. All clinically sick lambs had very high titres in the microscopic agglutination test for L. pomona. Circumstantial evidence of pigs being the source of infection was found in one of the three cases. 相似文献