Current Status of Viral and Phytoplasma Diseases Affecting Gerbera Cultivation and Their Management

2021 ◽  
Vol 55 (2) ◽  
pp. 133-150
Author(s):  
K. K. Gautam ◽  
S. Kumar ◽  
S. K. Raj

Gerbera (Gerbera jamesonii) is a popular ornamental plant cultivated all over the world. It is grown in beds, pots and used as cut-flower in making bouquets and for decoration in ceremonial functions. Gerbera has been commercially cultivated by a large number of growers in India as a primary source of income, therefore, has high socioeconomic impact in floriculture industry. The gerbera cultivation areas in India are increasing day by day due to its uses and the market demands. Its cultivation has been hampered by a variety of diseases that affect its flower quality and quantity. Of them, the viral and phytoplasma diseases cause considerable losses in gerbera cultivation. In this review, we have described about the disease symptoms, detection methods and identification of causal virus and phytoplasma pathogens affecting gerbera production worldwide and their disease management strategies opted by the researchers for production of pathogen-free plants.

2020 ◽  
Vol 15 (1) ◽  
pp. 93-96
Author(s):  
Aswath C ◽  
Rajiv Kumar

The present study was carried out to evaluate the performance of two gerbera hybrids IIHR15-7 and IIHR16-8 along with their parents and a commercial check, for flower quality traits under polyhouse condition in completely randomized block design, during 2016-17 to 2018-19. The hybrids IIHR15-7 and IIHR16-8 had been developed through the half-sib method of breeding with IIHR9 and Arka Ashwa, respectively, as parents. Data for three years were pooled and analyzed statistically. In both hybrids IIHR15-7 and IIHR16-8, all the quantitative traits were found to be on par with the respective commercial checks. They had novel flower colour (as per RHS Colour Chart) i.e. NN155A, White Group for IIHR 15-7 and 65A Red Purple Group for IIHR16-8, with semi-double and double forms of flowers, respectively. These hybrids are suitable for cut-flower and flower arrangement purposes. Further, these hybrids will be useful for developing new gerbera hybrids with novel traits.


Mousaion ◽  
2019 ◽  
Vol 36 (2) ◽  
Author(s):  
Ncamsile Nombulelo Dlamini ◽  
Maritha Snyman

The purpose of this paper is to assess the current status of institutional repositories (IRs) in Swaziland’s academic institutions. The factors under discussion are the number of IRs in Swaziland, their usage, the level of awareness of these IRs, and the challenges that prevent the implementation of IRs in Swaziland’s academic institutions. A webometric approach, interviews and semi-structured questionnaires completed by IR managers or librarians working for the Swaziland’s academic institutions were used to collect data for this study. Responses were received from 11 respondents. The findings indicated that there is one IR in Swaziland that is accessible to the institution’s community via the intranet. This IR was, at the time when this study took place, not registered in any of the international registries of repositories, such as the Registry of Open Access Repositories (ROAR) and the Directory of Open Access Repositories (OpenDOAR). Currently, this IR faces problems of insufficient content, a low level of IR awareness, limited knowledge of effective and appropriate IR advocacy strategies and limited knowledge of effective IR implementation and management strategies. Based on the findings and information gained from a literature review of IRs, the paper recommends strategies to academic institutions in Swaziland that may enable them to increase their number of IRs, the awareness level of IRs and consequently the use of IRs. The findings and recommendations may also benefit other African countries in similar situations.  


1993 ◽  
Vol 27 (7-8) ◽  
pp. 127-133 ◽  
Author(s):  
H. Dizer ◽  
J. Dürkop ◽  
A. Grohmann ◽  
H. Kopecka ◽  
J. M. López-Pila

Secondary effluent of wastewater treatment plants contains a high number of viruses and other pathogens, which pose a health risk to the population, (especially when receiv ng waters are used for bathing and swimming, or for growing shellfish. In areas with a high density of population, where drinking water supply is dependent on surface waters and contaminated rivers are the primary source of drinking water, failure of the filtration or of the disinfection step, or of any other “barriers” supposed to warrant safe potable water, will increase the risk of health hazard for the consumer. We have compared the efficiency of viral elimination in secondary effluent by flocculation, uv rradiation and membrane filtration taking naturally occurring, or additionally seeded f2 phages, as indicator for viruses. Flocculation decreased the number of phages present in secondary effluent by more than two logs. If combined with uv irradiation, the elimination reached five additional logs. Membrane filtration eliminated essentially all naturally occurring phages. Improvement of the quality of surface waters calls for a refinement of detection methods for viruses. We have found that the polymerase chain reaction (PCR) might be used for detecting viruses in surface waters.


Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 320
Author(s):  
Alexander Nilon ◽  
Karl Robinson ◽  
Hanu R. Pappu ◽  
Neena Mitter

Tomato spotted wilt virus (TSWV) is the type member of the genus Orthotospovirus in the family Tospoviridae and order Bunyavirales. TSWV, transmitted by several species of thrips, causes significant disease losses to agronomic and horticultural crops worldwide, impacting both the yield and quality of the produce. Management strategies include growing virus-resistant cultivars, cultural practices, and managing thrips vectors through pesticide application. However, numerous studies have reported that TSWV isolates can overcome host-plant resistance, while thrips are developing resistance to pesticides that were once effective. RNA interference (RNAi) offers a means of host defence by using double-stranded (ds) RNA to initiate gene silencing against invading viruses. However, adoption of this approach requires production and use of transgenic plants and thus limits the practical application of RNAi against TSWV and other viruses. To fully utilize the potential of RNAi for virus management at the field level, new and novel approaches are needed. In this review, we summarize RNAi and highlight the potential of topical or exogenous application of RNAi triggers for managing TSWV and thrips vectors.


2021 ◽  
Vol 27 (Supplement_1) ◽  
pp. S58-S59
Author(s):  
Megan Zangara ◽  
Natalie Bhesania ◽  
Wei Liu ◽  
Gail Cresci ◽  
Jacob Kurowski ◽  
...  

Abstract Background Dietary modification shows promise as therapy in inflammatory bowel disease (IBD); however, it is unknown whether adolescents are interested in a dietary approach. Methods Cross-sectional survey of adolescents with IBD ages 14–21 on disease knowledge, dietary habits, and perceptions of diet therapy. Results A total of 132 subjects (48.5% female), mean age of 17.8 years and median disease length of 5 years (range 0, 16), completed the survey. Diet was perceived as a symptom trigger by 59.8% of subjects, and 45.4% had tried using diet as a treatment for symptom resolution, often without physician supervision and with limited success. Overall, subjects reported following a diet significantly more often than documented in the electronic medical record (EMR) by the physician (25.0% vs. 15.0%, p=0.033), with 72% agreement between subject response and EMR documentation on current status of diet modification (AC1=0.59, CI=0.45, 0.73). Subjects experiencing active disease symptoms as determined by Manitoba IBD Index were more likely to be currently modifying their diet compared to subjects without active disease symptoms (OR = 4.11, CI=1.58, 10.73, p=0.003). The subjects reporting unsuccessful dietary modification compliancy (25.7%, n=34) most commonly cited perceived lack of improvement in their IBD symptoms as the primary reason for stopping the diet (48.4%, n=15). Conclusions Adolescents with IBD perceive a relationship between diet and disease symptoms and are interested in dietary modification as a symptom management option. Our study suggests that a large proportion of adolescent IBD patients may already be attempting dietary modification, and therefore would be receptive to a modified dietary plan under the guidance of their gastroenterologist and dietitian. Much is still unknown about how dietary modification will fit in with current treatment regimens, but patient interest informs us that it is necessary to continue development and research of this promising therapeutic option.


Parasitology ◽  
1999 ◽  
Vol 117 (7) ◽  
pp. 205-212 ◽  
Author(s):  
C. J. GIBSON ◽  
C. N. HAAS ◽  
J. B. ROSE

Throughout the past decade much research has been directed towards identifying the occurrence, epidemiology, and risks associated with waterborne protozoa. While outbreaks are continually documented, sporadic cases of disease associated with exposure to low levels of waterborne protozoa are of increasing concern. Current methodologies may not be sensitive enough to define these low levels of disease. However, risk assessment methods may be utilised to address these low level contamination events. The purpose of this article is to provide an introduction to microbial risk assessment for waterborne protozoa. Risk assessment is a useful tool for evaluating relative risks and can be used for development of policies to decrease risks. Numerous studies have been published on risk assessment methods for pathogenic protozoa including Cryptosporidium and Giardia. One common notion prevails: microbial risk assessment presents interesting complications to the traditional chemical risk assessment paradigm. Single microbial exposures (non-threshold) are capable of causing symptomatic illness unlike traditional chemical exposures, which require a threshold to be reached. Due to the lack of efficient recovery and detection methods for protozoa, we may be underestimating the occurrence, concentration and distribution of these pathogenic micro-organisms. To better utilize the tool of microbial risk assessment for risk management practices, future research should focus in the area of exposure assessment.


2018 ◽  
Vol 26 (2) ◽  
pp. 267-285 ◽  
Author(s):  
C. van Zyl ◽  
P. Addison ◽  
R. Veldtman

2017 ◽  
Vol 68 (5) ◽  
pp. 831 ◽  
Author(s):  
S. Valladares ◽  
D. X. Soto ◽  
M. Planas

The lack of integrated measures for assessing the feeding ecology of seahorses may restrict the effectiveness of conservation actions on wild populations of worldwide threatened seahorse species. Identifying dietary sources will allow researchers to determine their degree of vulnerability to environmental changes, redefine their conservation status and apply appropriate management strategies. The resource use of the seahorse Hippocampus guttulatus inhabiting coastal waters of Galicia (north-western Iberian Peninsula) was assessed for three populations and 2 years using stable isotope mixing models. The Bayesian mixing model (MixSIAR) estimated the relative contributions of the dietary sources to the seahorse diet and revealed that Caprellidea were the primary source, followed by Gammaridea and Caridea. Mysidae and Annelida represented the less dominant prey. This prey preference can be explained by the foraging behaviour of seahorses. Different contributions of Gammaridea and Caridea to the diet were found among sites, indicating different habitat characteristics and hence different habitat use by seahorses within each site. In addition, differences were encountered among sexes. Caprellidea was the dominant prey for females, whereas Gammaridea was the dominant prey for males. The findings of the present study will contribute to the knowledge of feeding patterns of H. guttulatus, providing relevant data for conservation of this endangered species.


2021 ◽  
Author(s):  
Divyesh Kumar

World over life was going at its normal pace when an outbreak occurred in Hubei province of China in the later part of the year 2019. This outbreak was soon found to be caused by a virus named coronavirus (COVID-19). Rapidly the virus spread globally leading to a pandemic. The mortality rate was increasing day by day and helplessly everyone was wondering what actually could be done to prevent the spread. Lessons from the past epidemic made it possible to think that maintaining social distancing and adequate hygiene might help to combat the ailment. In India, majorly affected were the people from poor strata and the businessmen who were earning their daily bread by selling things of daily need. The health sector too witnessed an alarming ratio of patients suffering from COVID-19. The second wave, which soon followd the first wave, caused much more havoc. Overall, the COVID-19 pandemic, exposed and challanged the health security system of every country. As the danger of pandemic still prevails, steps to curtail the spread of disease and future management strategies should be formulated from the lessons learnt through the COVID-19 phase.


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