The evolution of plant pathogens in response to host resistance: Factors affecting the gain from deployment of qualitative and quantitative resistance

2012 ◽  
Vol 304 ◽  
pp. 152-163 ◽  
Author(s):  
Giovanni Lo Iacono ◽  
Frank van den Bosch ◽  
Neil Paveley
Keyword(s):  
Host Resistance ◽  
Plant Pathogens ◽  
Quantitative Resistance ◽  
Factors Affecting ◽  
Resistance Factors ◽  
Qualitative And Quantitative

Mixed qualitative–quantitative approach for bidding decisions in construction

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Emad Mohamed ◽  
Parinaz Jafari ◽  
Ahmed Hammad
Keyword(s):  
Expert System ◽  
Expert Knowledge ◽  
The Body ◽  
Decision Makers ◽  
Quantitative Approach ◽  
Rule Based ◽  
Content Type ◽  
Factors Affecting ◽  
Qualitative And Quantitative ◽  
Mixed Approach

PurposeThe bid/no-bid decision is critical to the success of construction contractors. The factors affecting the bid/no-bid decision are either qualitative or quantitative. Previous studies on modeling the bidding decision have not extensively focused on distinguishing qualitative and quantitative factors. Thus, the purpose of this paper is to improve the bidding decision in construction projects by developing tools that consider both qualitative and quantitative factors affecting the bidding decision.Design/methodology/approachThis study proposes a mixed qualitative-quantitative approach to deal with both qualitative and quantitative factors. The mixed qualitative-quantitative approach is developed by combining a rule-based expert system and fuzzy-based expert system. The rule-based expert system is used to evaluate the project based on qualitative factors and the fuzzy expert system is used to evaluate the project based on the quantitative factors in order to reach the comprehensive bid/no-bid decision.FindingsThree real bidding projects are used to investigate the applicability and functionality of the proposed mixed approach and are tested with experts of a construction company in Alberta, Canada. The results demonstrate that the mixed approach provides a more reliable, accurate and practical tool that can assist decision-makers involved in the bid/no-bid decision.Originality/valueThis study contributes theoretically to the body of knowledge by (1) proposing a novel approach capable of modeling all types of factors (either qualitative or quantitative) affecting the bidding decision, and (2) providing means to acquire, store and reuse expert knowledge. Practical contribution of this paper is to provide decision-makers with a comprehensive model that mimics the decision-making process and stores experts' knowledge in the form of rules. Therefore, the model reduces the administrative burden on the decision-makers, saves time and effort and reduces bias and human errors during the bidding process.

scholarly journals Identifikasi Pseudomonas aeruginosa dan tes sensitivitas siprofloksasin pada abses periodontal Identification of Pseudomonas aeruginosa and sensitivity test of ciprofloxacin on periodontal abcess

2011 ◽  
Vol 10 (3) ◽  
pp. 151 ◽  
Author(s):  
Irene E. Rieuwpassa ◽  
Muliaty Yunus ◽  
I Wayan Suka Arsana
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Observational Study ◽  
Broad Spectrum ◽  
Host Resistance ◽  
Dna Gyrase ◽  
Common Type ◽  
Sensitivity Test ◽  
Bacterial Dna ◽  
Resistance Factors ◽  
Synthetic Drug

Periodontitis is a common type of periodontal disease caused by expansion of the early stages of gingivalinflammation. Expansion of inflammation to the tissue structures supporting the teeth can be modified by thepathogenic ability of plaque or host resistance factors. A total of 200 different bacteria have been identified on theplaque. Resistance to antimicrobials can be natural because the microbes develop mechanisms to defendthemselves. Ciprofloxacin is a synthetic drug of the second generation quinolones derivatives. Mechanism of itsaction is to inhibit the activity of bacterial DNA gyrase, which is bactericidal with a broad spectrum against Grampositiveor negative. This observational study identified P. aeruginosa and sensitivity test was performed tociprofloxacin in periodontal abscesses. Study conducted in 23 patients with periodontal abscess. Of those,Pseudomonas was acquired for 8 samples and 4 of them was resistant to ciprofloxacin.

scholarly journals Vermicomposting—Facts, Benefits and Knowledge Gaps

Agronomy ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1952
Author(s):  
Ana Vuković ◽  
Mirna Velki ◽  
Sandra Ečimović ◽  
Rosemary Vuković ◽  
Ivna Štolfa Čamagajevac ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Metal Content ◽  
Organic Waste ◽  
Plant Pathogens ◽  
Product Information ◽  
Knowledge Gaps ◽  
Factors Affecting ◽  
Quality Product ◽  
Waste Accumulation ◽  
High Quality Product

Industrialization and urbanization have led to an increased accumulation of waste materials that are transformed into a nutrient-rich and high-quality product called vermicompost by the vermicomposting process. Vermicomposting is an ecofriendly and economically favorable biotechnological process that involves the interaction of earthworms and microorganisms. Due to the importance of this process and its great potential in dealing with the consequences of waste accumulation, this review aims to provide key insights as well as highlight knowledge gaps. It is emphasized that there is a great challenge in understanding and clarifying the mechanisms involved in the vermicomposting process. The optimization of the factors affecting the possible application of vermicompost is crucial for obtaining the final product. Information on the composition of bacterial communities, amount of vermicompost, effect on heavy metal content, plant pathogens, diseases and organic waste selection is here recognized as currently the most important issues to be addressed. By answering these knowledge gaps, it is possible to enable wider utilization of vermicompost products.

scholarly journals Assessing the effects of quantitative host resistance on the life-history traits of sporulating parasites with growing lesions

2019 ◽  
Vol 286 (1912) ◽  
pp. 20191244 ◽  
Author(s):  
Melen Leclerc ◽  
Julie A. J. Clément ◽  
Didier Andrivon ◽  
Frédéric M. Hamelin
Keyword(s):  
Life History ◽  
Host Resistance ◽  
Life History Traits ◽  
Quantitative Resistance ◽  
Resistance Management ◽  
Latency Period ◽  
Scale Model ◽  
Infectious Period ◽  
Resistance Level ◽  
Phenotypic Data

Assessing life-history traits of parasites on resistant hosts is crucial in evolutionary ecology. In the particular case of sporulating pathogens with growing lesions, phenotyping is difficult because one needs to disentangle properly pathogen spread from sporulation. By considering Phytophthora infestans on potato, we use mathematical modelling to tackle this issue and refine the assessment of pathogen response to quantitative host resistance. We elaborate a parsimonious leaf-scale model by convolving a lesion growth model and a sporulation function, after a latency period. This model is fitted to data obtained on two isolates inoculated on three cultivars with contrasted resistance level. Our results confirm a significant host–pathogen interaction on the various estimated traits, and a reduction of both pathogen spread and spore production, induced by host resistance. Most interestingly, we highlight that quantitative resistance also changes the sporulation function, the mode of which is significantly time-lagged. This alteration of the infectious period distribution on resistant hosts may have strong impacts on the dynamics of parasite populations, and should be considered when assessing the durability of disease control tactics based on plant resistance management. This inter-disciplinary work also supports the relevance of mechanistic models for analysing phenotypic data of plant–pathogen interactions.

scholarly journals Specific Resistance of Barley to Powdery Mildew, Its Use and Beyond: A Concise Critical Review

Genes ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 971 ◽  
Author(s):  
Antonín Dreiseitl
Keyword(s):  
Powdery Mildew ◽  
Resistance Genes ◽  
Plant Pathogens ◽  
Specific Resistance ◽  
Wide Spectrum ◽  
Quantitative Resistance ◽  
Spring Barley ◽  
Durable Resistance ◽  
Genetic Resistance ◽  
Barley Cultivars

Powdery mildew caused by the airborne ascomycete fungus Blumeria graminis f. sp. hordei (Bgh) is one of most common diseases of barley (Hordeum vulgare). This, as with many other plant pathogens, can be efficiently controlled by inexpensive and environmentally-friendly genetic resistance. General requirements for resistance to the pathogens are effectiveness and durability. Resistance of barley to Bgh has been studied intensively, and this review describes recent research and summarizes the specific resistance genes found in barley varieties since the last conspectus. Bgh is extraordinarily adaptable, and some commonly recommended strategies for using genetic resistance, including pyramiding of specific genes, may not be effective because they can only contribute to a limited extent to obtain sufficient resistance durability of widely-grown cultivars. In spring barley, breeding the nonspecific mlo gene is a valuable source of durable resistance. Pyramiding of nonspecific quantitative resistance genes or using introgressions derived from bulbous barley (Hordeum bulbosum) are promising ways for breeding future winter barley cultivars. The utilization of a wide spectrum of nonhost resistances can also be adopted once practical methods have been developed.

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