scholarly journals Directed evolution of Metarhizium fungus improves its biocontrol efficacy against Varroa mites in honey bee colonies

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jennifer O. Han ◽  
Nicholas L. Naeger ◽  
Brandon K. Hopkins ◽  
David Sumerlin ◽  
Paul E. Stamets ◽  
...  
Keyword(s):  
Directed Evolution ◽  
Honey Bee ◽  
Entomopathogenic Fungi ◽  
Management Practices ◽  
Abiotic Factors ◽  
Control Measures ◽  
Residual Effects ◽  
Effective Control ◽  
Great Promise ◽  
Bee Colonies

AbstractEntomopathogenic fungi show great promise as pesticides in terms of their relatively high target specificity, low non-target toxicity, and low residual effects in agricultural fields and the environment. However, they also frequently have characteristics that limit their use, especially concerning tolerances to temperature, ultraviolet radiation, or other abiotic factors. The devastating ectoparasite of honey bees, Varroa destructor, is susceptible to entomopathogenic fungi, but the relatively warm temperatures inside honey bee hives have prevented these fungi from becoming effective control measures. Using a combination of traditional selection and directed evolution techniques developed for this system, new strains of Metarhizium brunneum were created that survived, germinated, and grew better at bee hive temperatures (35 °C). Field tests with full-sized honey bee colonies confirmed that the new strain JH1078 is more virulent against Varroa mites and controls the pest comparable to current treatments. These results indicate that entomopathogenic fungi are evolutionarily labile and capable of playing a larger role in modern pest management practices.

scholarly journals Comparative proteomic analysis of Fusarium oxysporum f. sp. cubense strains (Foc R1 and Foc TR4) provides better insights into mechanisms of their virulence, habitat adaptation and pathogenesis

2021 ◽  
Author(s):  
Thangavelu Raman ◽  
Kalaiponmani Kalaimughilan ◽  
Edwinraj Esack
Keyword(s):  
Fusarium Oxysporum ◽  
Management Practices ◽  
Response Regulator ◽  
Control Measures ◽  
Effective Control ◽  
Ph Response ◽  
Molecular Approaches ◽  
Regulator Protein ◽  
Fructose 1,6 Bisphosphate ◽  
Related Proteins

Fusarium oxysporum f. sp. cubense (Foc), a devastative soil-borne fungal pathogen causing vascular wilt (i.e. Panama disease) which leads to severe crop losses in most of the banana-growing regions of the world. As there is no single source of effective management practices available so far, understand the pathogenicity of the organism may help in designing effective control measures through molecular approaches. The study aims to compare the proteome of the two pathogenic Foc virulent strains, Race 1 (Foc R1) and tropical race 4 (Foc TR4) that are capable of infecting the Cavendish group of bananas using 2-dimensional (2-D) gel electrophoresis, MALDI-TOF/MS and MS/MS analysis. The results of the study revealed that the proteins, peroxiredoxins, NAD-aldehyde dehydrogenase (NAD-ALDH), MAPK protein, pH-response regulator protein palA/rim-20 and isotrichodermin C15 hydroxylase have shared homology with the fungal proteins, which regulate the osmotic stress response, signal transduction, root colonization and toxin biosynthesis. These are the important functions for the pathogen survival in an unfavourable environment, and successful establishment and infection of the banana host. The present study also identified several putative pathogenicity related proteins in both Foc R1 and Foc TR4. Specifically, certain Foc TR4 specific putative pathogenicity related proteins, phytotoxins biosynthesis gene, fructose 1,6-bisphosphate aldolase class II, Synembryn-like proteins found to contribute strong virulence. Overexpression or knockout of the elective genes could help in devising better control measures for the devastative pathogens in the future. To the best of our knowledge, this is the first report on the proteomics of Foc R1 and Foc TR4 strains of Indian origin that infect Cavendish bananas.

scholarly journals Critical Appraisal of Management Practices in Nepalese Guava Orchards

2005 ◽  
Vol 26 ◽  
pp. 127-133 ◽  
Author(s):  
AK Shrestha
Keyword(s):  
Management Practices ◽  
Critical Appraisal ◽  
Psidium Guajava ◽  
Control Measures ◽  
Effective Control ◽  
Peak Period ◽  
Rainfed Condition ◽  
Guava Fruit ◽  
Production Constraints ◽  
June July

A survey was conducted to appraise the guava farming in Nepal with respect to the orchard management practices, cultivar status and major production constraints during July- December 2001. Guava plantation was extensively distributed throughout terai, inner terai and mid hill districts ranging in altitude from 115 masl to 1600 masl. Indian varieties dominated the guava plantation in Nepal although mix population of both improved and local cultivars was reported in majority of orchards. Preponderance of seedling origin guava plantation was noticed. The management practices were poor. Over 80% of the orchards received neither FYM nor chemical fertilizer. Similarly, more than 90% of the orchards were under rainfed condition. The peak period of flowering was reported during April/May followed by Feb/March that may extend up to June/July. As a consequence, the fruit availability period is mainly restricted to four months, i.e. July/ August to Oct/Nov. Most of the growers pointed out guava wilt as the main biotic constraint in guava production. The outcomes indicted the urgent need to adopt the effective control measures against the guava wilt malady to flourish guava enterprise in Nepal. Furthermore, off-season production of guava fruit has the great potential in Nepalese market. Key words: cultivar, guava wilt, orchard, Psidium guajava J. Inst. Agric. Anim. Sci. 26:127-133 (2005)

scholarly journals Monitoring of Honey Bee Colony Losses: A Special Issue

Diversity ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 403
Author(s):  
Aleš Gregorc
Keyword(s):  
Honey Bee ◽  
Abiotic Factors ◽  
Special Issue ◽  
Colony Losses ◽  
Colony Management ◽  
Bee Colony ◽  
Honey Bee Colony ◽  
The Impact ◽  
Bee Colonies ◽  
Honey Bee Colony Losses

In recent decades, independent national and international research programs have revealed possible reasons for the death of managed honey bee colonies worldwide. Such losses are not due to a single factor, but instead are due to highly complex interactions between various internal and external influences, including pests, pathogens, honey bee stock diversity, and environmental change. Reduced honey bee vitality and nutrition, exposure to agrochemicals, and quality of colony management contribute to reduced colony survival in beekeeping operations. Our Special Issue (SI) on ‘’Monitoring of Honey Bee Colony Losses’’ aims to address specific challenges facing honey bee researchers and beekeepers. This SI includes four reviews, with one being a meta-analysis that identifies gaps in the current and future directions for research into honey bee colonies mortalities. Other review articles include studies regarding the impact of numerous factors on honey bee mortality, including external abiotic factors (e.g., winter conditions and colony management) as well as biotic factors such as attacks by Vespa velutina and Varroa destructor.

scholarly journals The distribution and population dynamics of the honey bee pathogens Crithidia mellificae and Lotmaria passim in New Zealand

2021 ◽  
Author(s):  
◽  
Tammy Leigh Waters
Keyword(s):  
Population Dynamics ◽  
New Zealand ◽  
Honey Bee ◽  
Management Practices ◽  
Bumble Bee ◽  
Strong Positive Correlation ◽  
Colony Losses ◽  
Positive Correlation ◽  
Bee Colonies ◽  
Lotmaria Passim

<p>The honey bee Apis mellifera is experiencing colony losses across the world, this is not the first time in history colony losses have been reported. New molecular detection methods such as real-time PCR allow the detection and analysis of pathogens present in colonies, quickly and reliably.  Of the pathogens that the honey bee is host to, trypanosomes are one of the least understood and trypanosome interactions within the honey bee host remain largely unknown. Using the bumble bee as a model for this host-parasite relationship. The trypanosome C. bombi is known to cause a reduced ability to gain nutrients from food and an overall decrease in efficiency of queens in founding colonies in spring. These negative correlations are significant enough in the bumble bee to warrant investigation into trypanosomes in the honey bee.  The trypanosome C. mellificae was first described in the honey bee in 1967. A screening study in 2009 included a test for and detected the trypanosome in modern honey bee samples. In 2013 C. mellificae was identified as a contributory factor to overwintering colony losses when co-infected with N. ceranae. Following studies detected trypanosomes and led to the characterisation of a new species, L. passim in 2013. Lotmaria passim was first detected in New Zealand in 2014 however no subsequent studies had been undertaken to identify the distribution and dynamics of trypanosomes in New Zealand honey bee colonies.  My goal in this study was to identify the presence of trypanosomes in New Zealand. In an overview study of 47 honey bee colonies from across New Zealand, 46 were positive for the L. passim species. Identified by sequencing of the GAPDH gene. A yearlong study of 15 colonies revealed that the infection rate of L. passim was consistent throughout the year and very low genetic variation was detected. Lotmaria passim was detected in all parts of New Zealand sampled in this study and often in high levels. A positive correlation was detected when L. passim was present in addition to N. apis. There was no detection of C. mellificae in my study. The lack of detection of C. mellificae may suggest that the species is not present, or that it is in such low levels it cannot yet be detected.  In parallel to this trypanosome study two Nosema spp. and DWV were also examined. Nosema apis was found to be more prevalent than N. ceranae, which was not present in any South Island samples. A strong positive correlation was detected between the two Nosema spp. DWV showed a high level of variation likely a reflection of differing Varroa management practices in apiaries in this study.  This study of trypanosomes is the first of its kind in New Zealand identifying the presence and population dynamics of L. passim. This in conjunction with data on Nosema spp. and DWV will be of value to the New Zealand apiculture industry and contribute to global honey bee health studies.</p>

scholarly journals A Regional, Honey Bee-Centered Approach Is Needed to Incentivize Grower Adoption of Bee-Friendly Practices in the Almond Industry

2021 ◽  
Vol 5 ◽  
Author(s):  
Jennie L. Durant ◽  
Lauren C. Ponisio
Keyword(s):  
Honey Bee ◽  
Cover Crops ◽  
Best Management Practices ◽  
Management Practices ◽  
Conservation Strategy ◽  
Pollination Services ◽  
Related Factors ◽  
Practice Adoption ◽  
Selection Framework ◽  
Bee Colonies

Managed and wild bee populations contribute over $15 billion in pollination services to US agriculture, yet both are declining or becoming increasingly vulnerable to parasites and disease. The loss of healthy and diverse forage is a key driver in bee declines, so incentivizing land managers to adopt diversified bee-friendly management practices such as forage plantings and reduced pesticide use can directly increase food security, pollinator health, and farmer adaptive capacity. To better understand what might incentivize growers to adopt bee-friendly practices, we conducted a survey of California almond growers, whose orchards are entirely dependent on bee pollination and draw nearly 88% of US bee colonies each February to pollinate almond bloom. We asked 329 respondents across all major almond growing regions of CA about their adoption rate and incentives for planting cover crops, pollinator habitat, and practicing the recommended and legally required bee-friendly best management practices, as well as their interest in bee-friendly certification programs. Using a model selection framework, we evaluated which geographic, social, operational, and pollination-service related factors were predictive of bee-friendly practice adoption. We found that no single factor was a statistically significant predictor of adoption across all models, suggesting there is no silver bullet determining bee-friendly practice adoption. However, we discovered that region and concerns about future pollination services consistently emerged as important factors related to all the practices we investigated, except the adoption of legally required BMPs. These findings suggest that a regionally flexible pollinator conservation strategy focused on supporting honey bee colonies might have the highest likelihood of grower participation and adoption.

scholarly journals Entomopathogenic fungi of the genus Beauveria and their pathogenicity to Ips typographus (Coleoptera: Curculionidae) in the Vitosha National Park, Bulgaria

2020 ◽  
Vol 66 (No. 10) ◽  
pp. 420-435
Author(s):  
Marek Barta ◽  
Danail Takov ◽  
Daniela Pilarska ◽  
Danail Doychev ◽  
Miriam Kádasi Horáková
Keyword(s):  
Entomopathogenic Fungi ◽  
Bark Beetles ◽  
National Park ◽  
Ips Typographus ◽  
Control Measures ◽  
Effective Control ◽  
Promising Alternative ◽  
The Difference ◽  
Highly Virulent

Ips typographus is a serious pest for forestry in Eurasia. Effective control is difficult due to its cryptic habits and insect pathogenic microorganisms, including entomopathogenic fungi that are believed to be a promising alternative to the traditional control measures of this pest. In 2018, diversity of entomopathogenic fungi of the genus Beauveria was studied in populations of I. typographus in the Vitosha National Park, Bulgaria. Two species, B. bassiana and B. caledonica, were identified and 33 in vitro strains were obtained. Phylogenetic positions of the strains were evaluated according to phylogenetic inferences based on ITS and TEF-1α. Pathogenicity of the strains against bark beetles was tested in laboratory. All strains were pathogenic, although there was some variability in the efficacy of B. bassiana strains. Virulence of the five most pathogenic strains (four B. bassiana strains and one B. caledonica strain) was compared with the commercial mycoinsecticide Boverol<sup>®</sup> and highly-virulent B. bassiana strain ARSEF 12957 isolated from I. typographus in Slovakia. The strain from Boverol<sup>®</sup> was least virulent and the Slovak strain ARSEF 12957 was more efficient than the Bulgarian strains, but the difference was not significant. The laboratory experiments suggest that the Bulgarian strains have a potential for the control of bark beetle adults.

scholarly journals Six decades of infectious bursal disease in poultry: The journey so far and challenges ahead

2021 ◽  
Vol 19 (3) ◽  
pp. 150-173
Author(s):  
N. Lawal ◽  
M.B. Bello
Keyword(s):  
Viral Vectors ◽  
Management Practices ◽  
Protein Structures ◽  
Control Measures ◽  
Infectious Bursal Disease ◽  
Effective Control ◽  
Poultry Production ◽  
Genetic Characteristics ◽  
Bursal Disease ◽  
Serotype 1

Despite six decades of concerted efforts, Infectious bursal disease (IBD) still remains a major threat to the poultry industry worldwide. Most importantly, the emergence of variant and very virulent strains of infectious bursal disease virus (IBDV) has dramatically changed the epidemiology of the disease, thus resulting in the renewed efforts in the search for effective control measures. Currently, live attenuated, inactivated, and immune-complex vaccines are among the immune-therapeutic approaches employed for the control of IBD in the field alongside adequate biosecurity, albeit with various degrees of success and limitations. Progress in genetic engineering has allowed the generation of reverse genetic IBDV mutants, recombinant live viral vectors expressing the IBDV VP2 immunodominant protein, intra-serotypic recombinant IBDV viral-like particle co-expressing the outer capsid protein structures derived from 2 or more serotype 1 strains or the incorporation of either VP2 or VP2-4-3 polyprotein sequences alongside molecular adjuvants that can be used as IBD vaccine candidates to elicit an immune response. However, despite these advances, outbreaks are still reported even in flocks that have up to date vaccination records and somewhat excellent management practices. This paper reviews aspect of genetic characteristics of IBDV and reflects on the progress and future challenges in providing effective IBD vaccine to achieve effective control of both classical and very-virulent IBDV serotypes that constitute a major devastation to poultry production and health.

scholarly journals The distribution and population dynamics of the honey bee pathogens Crithidia mellificae and Lotmaria passim in New Zealand

2021 ◽  
Author(s):  
◽  
Tammy Leigh Waters
Keyword(s):  
Population Dynamics ◽  
New Zealand ◽  
Honey Bee ◽  
Management Practices ◽  
Bumble Bee ◽  
Strong Positive Correlation ◽  
Colony Losses ◽  
Positive Correlation ◽  
Bee Colonies ◽  
Lotmaria Passim

<p>The honey bee Apis mellifera is experiencing colony losses across the world, this is not the first time in history colony losses have been reported. New molecular detection methods such as real-time PCR allow the detection and analysis of pathogens present in colonies, quickly and reliably.  Of the pathogens that the honey bee is host to, trypanosomes are one of the least understood and trypanosome interactions within the honey bee host remain largely unknown. Using the bumble bee as a model for this host-parasite relationship. The trypanosome C. bombi is known to cause a reduced ability to gain nutrients from food and an overall decrease in efficiency of queens in founding colonies in spring. These negative correlations are significant enough in the bumble bee to warrant investigation into trypanosomes in the honey bee.  The trypanosome C. mellificae was first described in the honey bee in 1967. A screening study in 2009 included a test for and detected the trypanosome in modern honey bee samples. In 2013 C. mellificae was identified as a contributory factor to overwintering colony losses when co-infected with N. ceranae. Following studies detected trypanosomes and led to the characterisation of a new species, L. passim in 2013. Lotmaria passim was first detected in New Zealand in 2014 however no subsequent studies had been undertaken to identify the distribution and dynamics of trypanosomes in New Zealand honey bee colonies.  My goal in this study was to identify the presence of trypanosomes in New Zealand. In an overview study of 47 honey bee colonies from across New Zealand, 46 were positive for the L. passim species. Identified by sequencing of the GAPDH gene. A yearlong study of 15 colonies revealed that the infection rate of L. passim was consistent throughout the year and very low genetic variation was detected. Lotmaria passim was detected in all parts of New Zealand sampled in this study and often in high levels. A positive correlation was detected when L. passim was present in addition to N. apis. There was no detection of C. mellificae in my study. The lack of detection of C. mellificae may suggest that the species is not present, or that it is in such low levels it cannot yet be detected.  In parallel to this trypanosome study two Nosema spp. and DWV were also examined. Nosema apis was found to be more prevalent than N. ceranae, which was not present in any South Island samples. A strong positive correlation was detected between the two Nosema spp. DWV showed a high level of variation likely a reflection of differing Varroa management practices in apiaries in this study.  This study of trypanosomes is the first of its kind in New Zealand identifying the presence and population dynamics of L. passim. This in conjunction with data on Nosema spp. and DWV will be of value to the New Zealand apiculture industry and contribute to global honey bee health studies.</p>

Key management practices to prevent high infestation levels of Varroa destructor in honey bee colonies at the beginning of the honey yield season

2016 ◽  
Vol 131 ◽  
pp. 95-102 ◽  
Author(s):  
Agostina Giacobino ◽  
Ana Molineri ◽  
Natalia Bulacio Cagnolo ◽  
Julieta Merke ◽  
Emanuel Orellano ◽  
...  
Keyword(s):  
Honey Bee ◽  
Varroa Destructor ◽  
Key Management ◽  
Management Practices ◽  
Bee Colonies ◽  
Honey Yield

scholarly journals Community knowledge and awareness of aflatoxin in dietary staples in rural Busia county, Kenya: A mixed methods study

2021 ◽  
Vol 21 (103) ◽  
pp. 18414-18434
Author(s):  
Abigael Obura Awuor ◽  
◽  
SD Okoth ◽  
FM Thuita
Keyword(s):  
Public Health ◽  
Management Practices ◽  
Health Workers ◽  
Animal Feed ◽  
Aflatoxin Contamination ◽  
Control Measures ◽  
Effective Control ◽  
Systematic Sampling ◽  
Surveillance Systems ◽  
Mitigation Options

Aflatoxins are an important food safety challenge globally and in Kenya. Understanding a community’s knowledge, perception and practices is instrumental to improvement of aflatoxin control measures. Creating awareness on the causes of contamination and mitigation options could improve aflatoxin mitigation. This study aimed to map out dietary staples, establish drivers of food choices, describe knowledge and perceptions on aflatoxin and post-harvest grain management practices and use among the communities in Busia County in order to guide future evidence-based aflatoxin prevention and public health interventions. A household survey was conducted in 40 villages, and participants were selected using stratified systematic sampling in three sub-counties in rural Busia County. The survey was complemented and triangulated with a qualitative study component. Focus Group Discussions with sixty women and sixteen semi- structured interviews with nine men and seven women were conducted. Both descriptive and statistical analysis of data were performed. The results showed variability in household diversity scores and maize was observed as the community staple. While both younger and older participants were able to identify spoilt grains, they demonstrated limited knowledge and awareness of aflatoxin. Participants were not aware that seemingly clean grains could be colonized by aflatoxin as they only associated spoilage with discoloration and bitter taste of flour. Study participants were also not aware of the aflatoxin pathways to exposure as they used the spoilt grains in feeding chicken, making animal feed and local brew. Appropriate disposal methods of aflatoxin contaminated food were not known. The knowledge gap was attributed to lack of awareness creation and sensitization by the relevant government ministries. For effective control and prevention of aflatoxin contamination, farmers and traders need to be aware of the causes of aflatoxin contamination of grains, available mitigation options and health risks attributable to aflatoxin exposure in order to self-regulate. Ministries of health and agriculture, through their public health officers, community health workers and agricultural extension officers respectively need to collaborate and spearhead awareness creation among communities and institute food surveillance systems in Busia County.

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