scholarly journals Evaluation of Bean Common Mosaic Disease and Associated Aphid Vector, Aphis fabae L., on Common Bean (Phaseolus vulgaris L.) Production in Lower Eastern Kenya

2021 ◽  
pp. 1-18
Author(s):  
Ngela A. Muute ◽  
Benjamin Muli ◽  
Orek Charles
Keyword(s):  
Common Bean ◽  
Management Strategies ◽  
Bean Common Mosaic Virus ◽  
Mosaic Disease ◽  
Aphis Fabae ◽  
Effective Control ◽  
Small Scale ◽  
Ecological Zones ◽  
Aphid Control ◽  
The Impact

Production of common bean in Kenya is constrained by pests and diseases and to improve bean yields amongst majority small-scale farmers, appropriate management strategies should be adopted. Bean common mosaic disease (BCMD) caused by bean common mosaic virus and vectored by bean aphids and infected seeds, substantially inhibit common bean production in Kenya. An extensive and diagnostic field survey was conducted in six agro ecological zones (AEZs) of lower eastern Kenya during the long and short rains of 2018 to determine BCMD incidence (BCMD-I), severity (BCMD-S), bean aphid abundance (BAA), bean aphid incidence (BAI) and the management strategies applied by farmers. Significant (P≤0.001) variations observed for these traits between bean varieties, rainy seasons and AEZs implied that farmers could select and grow a tolerant bean variety or grow a variety either in a season or an AEZ with low BCMD and bean aphid pressure. Such included AEZ-UMSA with least mean BCMD-I (42%), BCMD-S (1.9) and BAI (11%) compared to two AEZs (LHSH & LM4) that showed BCMD-I of >70%, BCMD-S >3.0 and BAI >50%. The AEZs differences could be attributed to variations in altitudes, temperature and humidity that influences vector (aphid) movement.  Of the nine  bean varieties identified during the survey, Selian 14 was the most preferred by farmers (at ~35%) with relatively lower BCMD-I (~49%) and BAI (~35%) compared to the least (<5%) farmer-preferred variety Wairimu that showed higher BCMD-I (56%) and BAI (~68%). Therefore variety Selian 14 was considered tolerant to BCMD and bean aphid. Significant (P≤0.001) and positive correlations (r = 0.67) between BAI and BCMD-I implied an effective control of bean aphids could reduce the impact of BCMD on bean production. On visual diagnostics, >75% of farmers could generally identify diseased or pest-infested bean crops and stage of growth of the crop most affected. None (0%) could however identify BCMD symptoms although ~40% identified the vector bean aphids with ~26% implementing some form of aphid or pest management strategy. On management, season-driven early planting and bean intercropping were the most applied strategies (>80%), crop rotation and weed control accounted for ~71%, certified seeds at 1% and non-chemical or pesticide applications (0%). Both low adoption of certified seeds and no chemical aphid control were attributed to high costs, despite the possibility the two factors could have contributed to higher incidences and severity of BCMD in the study area as the disease is both seed and vector-borne.  In summary, lack of knowledge and training among farmers on diagnosis and management of aphid-pests and BCMD, were cited as the main constraints for low bean cultivation. This study therefore recommends provision of adequate extension services and farmer training in lower eastern Kenya for improved bean yield and subsequent better family livelihoods and income.

scholarly journals Coping with abrupt environmental change: the impact of the coastal El Niño 2017 on artisanal fisheries and mariculture in North Peru

2018 ◽  
Vol 76 (4) ◽  
pp. 1122-1130 ◽  
Author(s):  
Lotta Clara Kluger ◽  
Sophia Kochalski ◽  
Arturo Aguirre-Velarde ◽  
Ivonne Vivar ◽  
Matthias Wolff
Keyword(s):  
El Niño ◽  
El Nino ◽  
Management Strategies ◽  
Small Scale ◽  
Artisanal Fisheries ◽  
Economic Activities ◽  
Economic Sectors ◽  
Wide Range ◽  
The Impact ◽  
Coastal El Niño

Abstract In February and March 2017, a coastal El Niño caused extraordinary heavy rains and a rise in water temperatures along the coast of northern Peru. In this work, we document the impacts of this phenomenon on the artisanal fisheries and the scallop aquaculture sector, both of which represent important socio-economic activities for the province of Sechura. Despite the perceived absence of effective disaster management and rehabilitation policies, resource users opted for a wide range of different adaptation strategies and are currently striving towards recovery. One year after the event, the artisanal fisheries fleet has returned to operating almost on a normal scale, while the aquaculture sector is still drastically impacted, with many people continuing to work in different economic sectors and even in other regions of the country. Recovery of the social-ecological system of Sechura likely depends on the occurrence of scallop seed and the financial capacity of small-scale producers to reinitiate scallop cultures. Long-term consequences of this coastal El Niño are yet to be studied, though the need to develop trans-local and trans-sectoral management strategies for coping with disturbance events of this scale is emphasized.

scholarly journals Verticillium Wilt of Olive and Its Control: What Did We Learn during the Last Decade?

Plants ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 735 ◽  
Author(s):  
Nuria Montes-Osuna ◽  
Jesús Mercado-Blanco
Keyword(s):  
Integrated Management ◽  
Management Strategies ◽  
Control Measures ◽  
Effective Control ◽  
Soil Biology ◽  
Pests And Diseases ◽  
Sensing Technology ◽  
Olive Cultivation ◽  
Underlying Mechanisms ◽  
The Impact

Verticillium (Verticillium dahliae Kleb.) wilt is one of the most devastating diseases affecting olive (Olea europaea L. subsp. europaea var. europaea) cultivation. Its effective control strongly relies on integrated management strategies. Olive cultivation systems are experiencing important changes (e.g., high-density orchards, etc.) aiming at improving productivity. The impact of these changes on soil biology and the incidence/severity of olive pests and diseases has not yet been sufficiently evaluated. A comprehensive understanding of the biology of the pathogen and its populations, the epidemiological factors contributing to exacerbating the disease, the underlying mechanisms of tolerance/resistance, and the involvement of the olive-associated microbiota in the tree’s health is needed. This knowledge will be instrumental to developing more effective control measures to confront the disease in regions where the pathogen is present, or to exclude it from V. dahliae-free areas. This review compiles the most recent advances achieved to understand the olive–V. dahliae interaction as well as measures to control the disease. Aspects such as the molecular basis of the host–pathogen interaction, the identification of new biocontrol agents, the implementation of “-omics” approaches to unravel the basis of disease tolerance, and the utilization of remote sensing technology for the early detection of pathogen attacks are highlighted.

scholarly journals Three Aphid-Transmitted Viruses Encourage Vector Migration From Infected Common Bean (Phaseolus vulgaris) Plants Through a Combination of Volatile and Surface Cues

2020 ◽  
Vol 11 ◽  
Author(s):  
Francis O. Wamonje ◽  
Trisna D. Tungadi ◽  
Alex M. Murphy ◽  
Adrienne E. Pate ◽  
Christine Woodcock ◽  
...  
Keyword(s):  
Phaseolus Vulgaris ◽  
Common Bean ◽  
Mosaic Virus ◽  
Bean Common Mosaic Virus ◽  
Sub Saharan Africa ◽  
Aphis Fabae ◽  
Choice Test ◽  
Generalist Species ◽  
Sub Saharan ◽  
Specialist Species

Bean common mosaic virus (BCMV), bean common mosaic necrosis virus (BCMNV), and cucumber mosaic virus (CMV) are important pathogens of common bean (Phaseolus vulgaris), a crop vital for food security in sub-Saharan Africa. These viruses are vectored by aphids non-persistently, with virions bound loosely to stylet receptors. These viruses also manipulate aphid-mediated transmission by altering host properties. Virus-induced effects on host-aphid interactions were investigated using choice test (migration) assays, olfactometry, and analysis of insect-perceivable volatile organic compounds (VOCs) using gas chromatography (GC)-coupled mass spectrometry, and GC-coupled electroantennography. When allowed to choose freely between infected and uninfected plants, aphids of the legume specialist species Aphis fabae, and of the generalist species Myzus persicae, were repelled by plants infected with BCMV, BCMNV, or CMV. However, in olfactometer experiments with A. fabae, only the VOCs emitted by BCMNV-infected plants repelled aphids. Although BCMV, BCMNV, and CMV each induced distinctive changes in emission of aphid-perceivable volatiles, all three suppressed emission of an attractant sesquiterpene, α-copaene, suggesting these three different viruses promote migration of virus-bearing aphids in a similar fashion.

scholarly journals Exploring the Impact and Management Strategies for Hailstorm Associated Loss and Damage among Smallholder Farmers in Poverty Prone Northern Bangladesh

2021 ◽  
Author(s):  
Mohammad Mahbubur Rahman ◽  
Mizanur Rahman Bijoy
Keyword(s):  
Climate Change ◽  
Smallholder Farmers ◽  
Human Life ◽  
Management Strategies ◽  
Sudden Onset ◽  
Primary Data ◽  
Small Scale ◽  
Weather Extremes ◽  
Loss And Damage ◽  
The Impact

Climate change causes weather extremes to rise in frequency and severity, which could have detrimental effects on human life, property and livelihood activity. There is significant uncertainty about the influences of anthropogenic climate change on the occurrence and severity of small-scale, sudden onset weather phenomena such as hailstorms and subsequent loss and damage. Yet, several studies indicate that there is an apparent stable connection between hailstorm activity and hailstorm damage. Severe hailstorm events are observed in Bangladesh in recent years, which are, in fact, rapid-onset disasters but low exposure in terms of giving government response and media consideration. Hence this study examines potential impacts and management strategies for loss and damage resulting from hailstorm events among smallholder farmers in Kurigram District's Phulbari Upazila of Bangladesh. Firstly, the direct and long term economic and non-economic loss and damage caused by the hailstorm on human well-beings and livelihoods were assessed. Then, the study evaluated the current adaptation, coping, management and response strategies at the institutional and community level in the context of such extreme events. Finally, a regulatory framework and implementation approaches had suggested achieving the country's resilience against disaster and climate change-induced loss and damage. Participatory Vulnerability Analysis, Key Informant Interviews and Sample Surveys accumulated the primary data for the study. In addition, secondary data were collected through analysis of literature, published and unpublished scientific articles and media reports, etc. This research outcome will help countries develop a guideline to address climate change and disaster-related loss and damage.

Effect of herbicide and application of superphosphate and subterranean clover seed on regeneration of vulpia in pastures

1997 ◽  
Vol 37 (4) ◽  
pp. 431 ◽  
Author(s):  
P. M. Dowling ◽  
A. R. Leys ◽  
B. Plater
Keyword(s):  
New South ◽  
Management Strategies ◽  
Subterranean Clover ◽  
Effective Control ◽  
Wagga Wagga ◽  
Permanent Pasture ◽  
South Wales ◽  
Clover Seed ◽  
High Level ◽  
The Impact

Summary. The annual grass vulpia has become one of the main weed problems in permanent pasture and cropping areas across southern Australia. The effect of herbicides and management (application of superphosphate and subterranean clover seed) on regeneration of vulpia in pasture was evaluated over a 2 year period at 6 sites in central and southern New South Wales (Beckom, Wagga Wagga, Eugowra, Bathurst, Holbrook and Millthorpe) during 1989–91. Four herbicide strategies (nil, spraytopping with paraquat in spring 1989, winter cleaning with simazine in winter 1990, and spraytopping with paraquat in spring 1989 followed by winter cleaning with simazine in 1990) were evaluated at a low (no added superphosphate or subterranean clover seed) and high level (250 kg/ha additional superphosphate applied in autumn 1989 and again in autumn 1990, plus 10 kg/ha subterranean clover seed broadcast in 1989) of management. Herbicides decreased the incidence of vulpia (as assessed from seedling density and pasture composition measurements) at low and high levels of management, with simazine and the combined paraquat plus simazine treatment providing more effective control than paraquat. The population of vulpia, however, increased rapidly on both the simazine and paraquat treatments with time. On the paraquat plots, this resulted in a similar or greater vulpia density as the unsprayed control within 2 years of application. The higher level of management encouraged greater density of subterranean clover and nitrophilous species (e.g. barley grass where present), resulting in greater competition against vulpia, and extending the period of control conferred initially by the herbicides. Control of vulpia over the longer term will require integration of herbicides with other management strategies (e.g. superphosphate, additional seed, careful grazing management). Such an approach needs to be implemented on a more regular basis than is currently practised if the impact of vulpia in pastures is to be minimised.

West Indian Canefly (Hemiptera: Delphacidae): An Emerging Pest of Louisiana Sugarcane

2019 ◽  
Vol 113 (1) ◽  
pp. 263-272 ◽  
Author(s):  
B E Wilson ◽  
J M Beuzelin ◽  
R T Richard ◽  
R M Johnson ◽  
K A Gravois ◽  
...  
Keyword(s):  
Management Strategies ◽  
Ecological Factors ◽  
West Indian ◽  
Effective Control ◽  
Future Research ◽  
Yield Data ◽  
Grid Sampling ◽  
Economic Thresholds ◽  
Small Plot ◽  
The Impact

Abstract The West Indian canefly, Saccharosydne saccharivora (Westwood) (Hemiptera: Delphacidae), is a sporadic pest of sugarcane in Louisiana which has recently emerged as a more consistent threat with outbreaks occurring in 2012, 2016, 2017, and 2019. Surveys of commercial fields in 2016 revealed that S. saccharivora infestations were present throughout Louisiana sugarcane and populations peaked in mid-June before declining. High minimum winter temperatures are generally associated with S. saccharivora outbreaks. Six insecticide evaluations demonstrated effective control with several insecticides including λ-cyhalothrin, flupyradifurone, acetamiprid, and imidacloprid. In five of the six insecticide trials, S. saccharivora infestations had substantially declined by 21 d after treatment. Effects of insecticidal control of S. saccharivora on sugar yields were detected in one of four small plot trials in which yield data were collected. Linear regression revealed S. saccharivora cumulative insect days in a grid sampling study were inversely associated with sugar yields. Results from these collective experiments suggest impacts on sugar yields are influenced by pest density and infestation duration. Differences were detected in numbers of S. saccharivora nymphs and adults as well as sooty mold coverage among commercial sugarcane cultivars with more than twofold increases in the most susceptible compared to resistant cultivars. The research presented herein documents the impact of S. saccharivora to Louisiana sugarcane and provides important ground work for developing effective pest management strategies. Future research efforts should aim to identify ecological factors influencing population dynamics, varietal preferences, and economic thresholds.

scholarly journals Molecular Detection and Quantification of the Striga Seedbank in Ethiopian Sorghum Field Soils

2021 ◽  
Author(s):  
Jos Raaijmakers ◽  
Getahun Mitiku ◽  
Desalegn Etalo ◽  
Paulien KleinGunnewiek ◽  
Dominika Rybka ◽  
...  
Keyword(s):  
Agricultural Soils ◽  
Quantitative Polymerase Chain Reaction ◽  
Management Strategies ◽  
Sub Saharan Africa ◽  
Ecological Zones ◽  
Diverse Field ◽  
Field Soils ◽  
Size Based Separation ◽  
The Impact ◽  
Detection And Quantification

Abstract Aims Striga hermonthica is a devastating parasitic weed in Sub-Saharan Africa (SSA) and its persistent soil seedbank is the major contributing factor for its prevalence and persistence. So far, there is little to no information on the Striga seedbank density in agricultural fields in SSA due to the lack of reliable detection and quantification methods. Methods We developed a high-throughput method that combines density- and size-based separation techniques with quantitative polymerase chain reaction (qPCR)-based detection of Striga seeds in soil. The method was optimized and validated on two physicochemically different Striga-free Dutch agricultural soils by introducing increasing numbers of Striga seeds (0, 1, 3, 9, 27, 81 and 243 seeds). Results The results showed that as little as one seed of S. hermonthica per 150 g of soil can be detected. This technique was subsequently tested on soil samples of 48 sorghum fields from different agro-ecological zones in Ethiopia to map the geospatial distribution of the Striga seedbank along a trajectory of more than 1500 km. Considerable variation in Striga seed densities was observed for these soils: in 75% of the field soils, Striga seeds were detectable up to 86 seeds per 150 g of soil. Correlation analyses further revealed a significant non-linear relationship between the seed density and Striga incidence assessed in the same sorghum field soils at the time of soil sampling. Conclusions The method developed allows for high-through-put and accurate mapping of the Striga seedbank in physicochemically diverse field soils and can be used to predict Striga incidence and to assess the impact of management strategies on Striga seedbank dynamics.

Can Values of Honesty, Hard Work, Loyalty and Discipline Predict Entrepreneurial Orientation of Muslim Owner Managers?

2015 ◽  
Vol 3 (1) ◽  
pp. 31 ◽  
Author(s):  
Rohani Mohd ◽  
Badrul Hisham Kamaruddin ◽  
Khulida Kirana Yahya ◽  
Elias Sanidas
Keyword(s):  
Entrepreneurial Orientation ◽  
Two Dimensions ◽  
Hard Work ◽  
Small Scale ◽  
Sampling Frame ◽  
Policy Makers ◽  
Learning Institutions ◽  
Innovative Orientation ◽  
The Impact ◽  
True Values

The purpose of the present study is twofold: first, to investigate the true values of Muslim owner managers; second, to examine the impact of these values on entrepreneurial orientations of Muslim small-scale entrepreneurs. 850 Muslim owner managers were selected randomly using the sampling frame provided by MajlisAmanah Rakyat Malaysia (MARA). 162 completed questionnaires were collected and analyzed. For this paper only two dimensions of entrepreneurial orientations were analyzed: proactive orientation and innovative orientation. Interestingly, the findings revealed that Muslim businessmen/women are honest, loyal, disciplined and hard working. Loyalty and honesty are positively related to proactive orientation, while discipline and hard-work are positively related to innovative orientation. The findings provide implications for existing relevant theories, policy makers, practitioners and learning institutions. 

Characterizing the effectiveness of COVID-19 mitigation measures: A data-centric approach (Preprint)

2020 ◽  
Author(s):  
Lukman Olagoke ◽  
Ahmet E. Topcu
Keyword(s):  
Control Measure ◽  
Control Measures ◽  
World Health ◽  
Mitigation Measures ◽  
Effective Control ◽  
The World ◽  
Decision Making Processes ◽  
And Performance ◽  
Health Organization ◽  
The Impact

BACKGROUND COVID-19 represents a serious threat to both national health and economic systems. To curb this pandemic, the World Health Organization (WHO) issued a series of COVID-19 public safety guidelines. Different countries around the world initiated different measures in line with the WHO guidelines to mitigate and investigate the spread of COVID-19 in their territories. OBJECTIVE The aim of this paper is to quantitatively evaluate the effectiveness of these control measures using a data-centric approach. METHODS We begin with a simple text analysis of coronavirus-related articles and show that reports on similar outbreaks in the past strongly proposed similar control measures. This reaffirms the fact that these control measures are in order. Subsequently, we propose a simple performance statistic that quantifies general performance and performance under the different measures that were initiated. A density based clustering of based on performance statistic was carried out to group countries based on performance. RESULTS The performance statistic helps evaluate quantitatively the impact of COVID-19 control measures. Countries tend show variability in performance under different control measures. The performance statistic has negative correlation with cases of death which is a useful characteristics for COVID-19 control measure performance analysis. A web-based time-line visualization that enables comparison of performances and cases across continents and subregions is presented. CONCLUSIONS The performance metric is relevant for the analysis of the impact of COVID-19 control measures. This can help caregivers and policymakers identify effective control measures and reduce cases of death due to COVID-19. The interactive web visualizer provides easily digested and quick feedback to augment decision-making processes in the COVID-19 response measures evaluation. CLINICALTRIAL Not Applicable

scholarly journals Land Subsidence Estimation for Aquifer Drainage Induced by Underground Mining

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4658
Author(s):  
Artur Guzy ◽  
Wojciech T. Witkowski
Keyword(s):  
Environmental Impact ◽  
Land Subsidence ◽  
Field Data ◽  
Underground Mining ◽  
Small Scale ◽  
Aquifer System ◽  
Maximum Value ◽  
The Impact ◽  
Method Model ◽  
Impact Of Mining

Land subsidence caused by groundwater withdrawal induced by mining is a relatively unknown phenomenon. This is primarily due to the small scale of such movements compared to the land subsidence caused by deposit extraction. Nonetheless, the environmental impact of drainage-related land subsidence remains underestimated. The research was carried out in the “Bogdanka” coal mine in Poland. First, the historical impact of mining on land subsidence and groundwater head changes was investigated. The outcomes of these studies were used to construct the influence method model. With field data, our model was successfully calibrated and validated. Finally, it was used for land subsidence estimation for 2030. As per the findings, the field of mining exploitation has the greatest land subsidence. In 2014, the maximum value of the phenomenon was 0.313 cm. However, this value will reach 0.364 m by 2030. The spatial extent of land subsidence caused by mining-induced drainage extends up to 20 km beyond the mining area’s boundaries. The presented model provided land subsidence patterns without the need for a complex numerical subsidence model. As a result, the method presented can be effectively used for land subsidence regulation plans considering the impact of mining on the aquifer system.

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