scholarly journals Citrus leprosis virus C (leprosis of citrus).

Author(s):  
John S. Hartung ◽  
M. Guillermo León

Abstract CiLV-C is a quarantine pest which causes an economically important disease, reported only on the American continent. During the past 15 years, it has caused economic losses in Brazil, Argentina, Paraguay, Uruguay, Venezuela, Costa Rica, Panamá and Honduras. The disease was recently reported in Guatemala, Bolivia, México, Colombia and Belize. It is a threat to citrus-producing countries where the disease has not been reported. The disease can cause 100% yield loss (Rodrigues et al., 2000).

2021 ◽  
Author(s):  
John S. Hartung ◽  
M. Guillermo León

Abstract CiLV-C is a quarantine pest which causes an economically important disease, reported only on the American continent. During the past 15 years, it has caused economic losses in Brazil, Argentina, Paraguay, Uruguay, Venezuela, Costa Rica, Panamá and Honduras. The disease was recently reported in Guatemala, Bolivia, México, Colombia and Belize. It is a threat to citrus-producing countries where the disease has not been reported. The disease can cause 100% yield loss (Rodrigues et al., 2000). CiLV does not appear to move systemically in the host plant but can move short distances from a grafted shoot tip to the adjacent scion tissue. Accordingly, movement in latently infected planting material is not likely to be a major pathway for CiLV-C because of its non-systemic infection, CiLV-C can only be important where attacks by its vector mites are significant. The main means of movement and dispersal of the virus is via the vector mites of the genus Brevipalpus, which colonize most species of Citrus and many other plant species.


1962 ◽  
Vol 60 (1) ◽  
pp. 1-20 ◽  
Author(s):  
Margaret D. Beech ◽  
A. E. Duxbury ◽  
Peter Warner

This paper consists of an epidemiological study of 52 cases of Q fever occurring in metropolitan Adelaide in 1957 and also a description of the results of a survey of 516 sera obtained from abattoir workers.The only case occurring outside the abattoirs was a dairy farmer who probably became infected while visiting the abattoirs. If this were so the incubation period (35 days) of his disease would have been exceptionally long.The general features of the outbreak, which lasted several months, differed from those on the North American continent in that the latter occurred explosively within a few days with very high attack rates. The situation in the Adelaide abattoirs is similar to that in Brisbane, where the disease appears to be endemic. However, unlike in Adelaide, cases are commonly recognized outside the abattoirs in Brisbane.In the abattoirs the disease affected mainly inspectors, those working on killing beef, and those working on offal. Mutton workers were not so severely affected. However, all these groups had similar incidences of low titre antibodies suggesting that in the past Q fever spread equally in all killing departments. In departments not directly associated with slaughtering the incidence both of cases in 1957 and low titre antibodies was relatively small.It was suggested that the epidemiological features of Q fever in Adelaide could be explained by the irregular appearance of animals from infected herds situated perhaps in Queensland—a known endemic area. Perhaps the appearance of such animals in the Adelaide abattoirs might be governed by meteorological conditions such that they were prevented from going to the ordinarily most convenient slaughterhouse.


2017 ◽  
Vol 2017 ◽  
pp. 1-5 ◽  
Author(s):  
Getachew Gari ◽  
Biressaw Serda ◽  
Dejene Negesa ◽  
Fethu Lemma ◽  
Hagos Asgedom

Peste des petits ruminant (PPR) is an economically important disease of small ruminants with a rapidly expanding geographical distribution. There are fragmented reports to the occurrence and distribution of the disease in Ethiopia. A total of 700 serum samples were collected from goats and sheep to detect the presence of antibody against PPR virus using Competitive Enzyme-Linked Immunosorbent Assay (C-ELISA). An overall PPR seropositivity was reported to be 48.43% in the area. There is no statistically significant difference in the seroprevalence of the disease between sheep and goats (50.85% and 46.68%), respectively. However, there was statistically significant variation (P<0.05) in the seroprevalence of the disease in young (33.9%) and adult (55.8%) age categories. The seroprevalence in male and female was 42.07% and 50.09%, respectively, where the variation was statistically not significant (P>0.05). High seroprevalence of Peste des petites ruminants in the study area indicated the virus circulation and endemicity of the disease. The disease causes substantial economic losses by affecting the livelihood of the farmers. Therefore, control measures should be put in place to minimize the loss associated with the disease.


2021 ◽  
Vol 25 (1) ◽  
pp. 1-22
Author(s):  
MP Ali ◽  
B Nessa ◽  
MT Khatun ◽  
MU Salam ◽  
MS Kabir

The damage caused by insect pest is the continual factor for the reduction of rice production. To date, 232 rice insect pest species are identified in Bangladesh and more than 100 species of insects are considered pests in rice production systems globally, but only about 20 - 33 species can cause significant economic loss. The major goal of this study is to explore all the possible ways of developed and proposed technologies for rice insect pests management and minimize economic losses. Insect pests cause 20% average yield loss in Asia where more than 90% of the world's rice is produced. In Bangladesh, outbreak of several insects such as rice hispa, leafroller, gallmidge, stem borers and brown planthopper (BPH) occurs as severe forms. Based on previous reports, yield loss can reach upto 62% in an outbreak situation due to hispa infestation. However, BPH can cause 44% yield loss in severe infestested field. To overcome the outbreaks in odd years and to keep the loss upto 5%, it is necessary to take some preventive measures such as planting of resistant or tolerant variety, stop insecticide spraying at early establishment of rice, establish early warning and forecasting system, avoid cultivation of susceptible variety and following crop rotation. Subsequent quick management options such as insecticidal treatment for specific insect pest should also be broadcasted through variety of information systems. Advanced genomic tool can be used to develop genetically modified insect and plants for sustainable pest management. In addition, to stipulate farmers not use insecticides at early crop stgae and minimize general annualized loss, some interventions including training rice farmers, regular field monitoring, digitalization in correct insect pests identification and their management (example; BRRI rice doctor mobile app), and demonstration in farmers field. Each technology itself solely or combination of two or more or all the packages can combat the insect pests, save natural enemies, harvest expected yield and contribute to safe food production in Bangladesh. Bangladesh Rice J. 25 (1) : 1-22, 2021


2011 ◽  
Vol 8 (3) ◽  
pp. 694-698
Author(s):  
Baghdad Science Journal

Newcastle Disease is one of the most important disease world wide distributions which invade the flock in different age resulting in large economic losses. This study aimed to evaluate the effect of treatment with 4 different concentrations (0.25, 0.5, 1.0 and 2.0 %) of Sodium deoxycholate (SDC) on the vaccinal virus (La Sota) using inoculation in the fragments of Chorioallantoic membrane. The treatment with each of the above 4 concentrations of SDC resulted in an increase in the Hemagglutination titer (HA) of the virus (28, 29.6, 211.6, 214.6) respectively as compared to the HA titer value for the untreated virus (26.6). No significant differences were noticed among all concentrations with regard to their effect on the HA titer, except the concentrations of 1.0 and 2.0 % where significant differences were recorded (P > 0.05). The results of this study suggest that SDC has an important activity in enhancement of the replication of NDV through increasing the Hemagglutination titer, which has a great importance in vaccine production.


Author(s):  
Fernando Cid Lucas
Keyword(s):  

En el presente artículo se analiza la presencia de americanismos insertos en las letras de algunas de las guajiras flamencas más conocidas en el repertorio pasado y actual del flamenco. Por otra parte, se comentarán algunos errores de pronunciación de dichos vocablos venidos desde el continente americano en los que han caído cantaores y cantaoras flamencos. In this article we will analyze the presence of several Americanisms inserted in the lyrics of some of the best known flamenco guajiras in the past and current repertoire of flamenco. In the same way, some solutions will be given to some errors of pronunciation of those words coming from the American continent made by flamenco singers.


2018 ◽  
Vol 69 (1) ◽  
pp. 711 ◽  
Author(s):  
I. SYMEONIDOU ◽  
E. BONOS ◽  
K. MOUSTAKIDIS ◽  
P. FLOROU-PANERI ◽  
E. CHRISTAKI ◽  
...  

Parasites (protozoa, helminthes, arthropods) represent a main threat for poultry worldwide. Among helminthes, nematodes constitute the most important group of parasites of poultry. The nematode Ascaridia galli, the cause of ascaridiosis in poultry, is one of the most important and prevalent parasites, resulting in serious economic losses, associated with the treatment cost, the decreased feed efficiency, and the poor egg and meat production. During the past few decades the indiscriminate use of anthelmintic drugs has generated several cases of resistance in helminthes in poultry, situation which is coupled with the severity of residues in poultry products. For this reason, nowadays attention has been drawn to the use of botanicals in poultry diet, due to their anthelmintic properties. Furthermore, the dietary use eco-friend ly of these plant derived substances compared to conventional synthetic anthelmintic drugs is considered as a natural and ecofriendly approach by the consumers. The focus of the present review is to recapitulate the studies, both in vivo and in vitro, that have demonstrated the anthelmintic efficacy of various dietary botanicals in controlling poultry ascaridiosis.


2015 ◽  
Vol 5 (4) ◽  
pp. 76 ◽  
Author(s):  
Yu-Shou Su

<p>Taiwan has performed well economically during the past four decades. However, economic development can be profoundly hampered by natural disasters. Sustainable economic development requires environmental resilience. With 23 million people occupying only 13,974 square miles of land, Taiwan is both densely populated and highly exposed to natural disasters: 73.1% of the total population lives in vulnerable areas, and Taiwan is ranked as the country most exposed to multiple hazards (The World Bank, 2005). Storms and floods damage Taiwan frequently, with an average of six typhoons hitting Taiwan annually for the past four decades. Taiwan had the highest occurrence and highest death toll on the natural disaster density indicator (NDDI) in comparison with China, Japan, U.S.A, U.K., France, and the Netherlands from 1985 to 2014. Also, Taiwan’s economic losses during the past thirty years are estimated at $650, 000 per km². This is approximately 5 times that of the Netherlands’ $134,362 and the U.K.’s $135,292, 8 times that of the U.S.A.’s $78,186 losses, and 9 times that of France’s $70,599. Research finds that every dollar invested into disaster preparedness would save $4 to $7 dollars in post-disaster damages (Multihazard Mitigation Council, 2005; The National Academy of Sciences, 2012). Hence, promoting urban resilience policies for disaster risk reduction should become a priority in Taiwan and other Asian nations in the future. Most important is the need of a strong political commitment and leadership to initiate and implement spatial policies toward resilience.</p>


2020 ◽  
Vol 11 ◽  
Author(s):  
Mikhail Oliveira Leastro ◽  
Deibis Yorlenis Ortega Castro ◽  
Juliana Freitas-Astúa ◽  
Elliot Watanabe Kitajima ◽  
Vicente Pallás ◽  
...  

Electronics ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 539 ◽  
Author(s):  
Chia-Ling Huang ◽  
Sin-Yuan Huang ◽  
Wei-Chang Yeh ◽  
Jinhai Wang

The transportation network promotes key human development links such as social production, population movement and resource exchange. As cities continue to expand, transportation networks become increasingly complex. A bad traffic network design will affect the quality of urban development and cause regional economic losses. How to plan transportation routes and allocate transportation resources is an important issue in today’s society. This study uses the network reliability method to solve traffic network problems. Network reliability refers to the probability of a successful connection between the source and sink nodes in the network. There are many systems in the world that use network architecture; therefore, network reliability is widely used in various practical problems and cases. In the past, some scholars have used network reliability to solve traffic service network problems. However, the processing of time is not detailed enough to fully express the real user’s time requirements and does not consider that the route traffic will affect the reliability of the entire network. This study improves on past network reliability methods by using a fuzzy system and a time window to construct a network model. Using the concept of fuzzy systems, according to past experience, data or expert predictions to define the degree of flow, time and reliability, can also determine the relationship between these factors. The time window can be adjusted according to the time limit in reality, reaching the limit of the complete expression time. In addition, the network reliability algorithm used in this study is a direct algorithm. Compared with the past indirect algorithms, the computation time is greatly reduced and complex problems can be solved more efficiently.


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