scholarly journals Population Fluctuation of Rice Leaffolder, (Cnaphalocrocis medinalis) in Two Consecutive Rice Seasons

2021 ◽  
Vol 12 (1) ◽  
pp. 10-22
Author(s):  
Marina Roseli ◽  
Nur Azura Adam ◽  
Lau Wei Hong ◽  
Salmah Yaakop
Keyword(s):  
Management Practices ◽  
Abiotic Factors ◽  
Pearson Correlation ◽  
Weather Condition ◽  
Population Fluctuation ◽  
Future Research ◽  
Cnaphalocrocis Medinalis ◽  
Significant Interaction Effect ◽  
Plant Stage ◽  
Rice Leaffolder

Larvae of rice leaffolder, Cnaphalocrocis medinalis attack rice crop at all three phases (from tillering until maturity stages). Their population throughout season was influenced by abiotic and biotic factors. Study on population fluctuation is important to understand the population dynamic and its factors in natural field condition. Thus, a study of population fluctuation of C. medinalis was conducted at rice field in Semanggol, Perak. Larvae were collected from 10 rice hills per plot in three 15 m x 4 m plots started on April 5, 2015 until June 7, 2015 (off season) and from October 25, 2015 until December 27, 2015 (main season). Abiotic data namely temperature, relative humidity (RH) and rainfall were obtained from Department of Meteorology Malaysia. Comparison of C. medinalis population between two seasons at different weeks was analysed using two-way ANOVA. The relationship of C. medinalis population with abiotic factors was analysed using Pearson correlation and stepwise regression. There was a significant interaction effect between season and week (F9,40=2.19; p<0.05). The highest population was recorded at week 55 day after transplanting (DAT) in main season comprised of 17% of total collection, followed by week 62 in off season (14%), week 48-main season (13%) and week 55-off season (13%). There was a positive correlation between C. medinalis population and RH in main and off season with RH was the key factor in regulating population in both seasons. Our results revealed that population of C. medinalis at different weeks was influenced by season. It is due to differences of weather condition between seasons, management practices and plant stages. The highest population recorded during reproductive phase is due to the morphology of rice plant that offers great suitability for larvae feeding and development. The abiotic factors also influenced C. medinalis population. Therefore, the abiotic factors should be considered in management of C. medinalis besides the plant stage and fertilizer effect. Future research on effect of natural enemies on C. medinalis population in field is needed in order to gain a better understanding of the factors that influence the population.

scholarly journals Water Management for Improving Pearl Millet Production under Irrigated Environment: A Review

2021 ◽  
Author(s):  
Parveen Kumar ◽  
Amit Kumar
Keyword(s):  
Water Management ◽  
Pearl Millet ◽  
Management Practices ◽  
Abiotic Factors ◽  
Research Work ◽  
Nutrient Status ◽  
Crop Productivity ◽  
Irrigation Scheduling ◽  
Future Research ◽  
Dry Land

Pearl millet also called “poor man food” is known for its drought resistance, well adaptation to harsh conditions like soils with poor water holding capacity, low nutrient status, problematic soils, etc. Irrigation has been recognized as a basic necessity for sustaining high productivity of various crops. Moreover, it affects the crop yield directly as well as indirectly by increasing their response to other inputs including fertilizers and various management practices. It is well known that water deficit is one of the major abiotic factors limiting crop productivity in the semi-arid tropics. Out of the various production constraints; low productivity of pearl millet is mainly attributed to its cultivation under dry land conditions and improper water management under irrigated conditions. So application of irrigation water offers the scope for improving the quality as well as productivity of pearl millet. Therefore, to augment the productivity of the poor’s man crop, review of the research work related to irrigation scheduling and moisture conservation practices of pearl millet has been presented here for directing the future research.

How soil abiotic factors affect the population fluctuation of Leitneria pugio (Acari: Mesostigmata: Halolaelapidae)

2021 ◽  
Author(s):  
Sahebeh Ghasemi-Moghadam ◽  
Ali Ahadiyat ◽  
Yaghoub Fathipour ◽  
Alireza Saboori
Keyword(s):  
Spatial Distribution ◽  
Population Density ◽  
Distribution Pattern ◽  
Abiotic Factors ◽  
Pearson Correlation ◽  
Negative Relationship ◽  
Predatory Mite ◽  
Spatial Distribution Pattern ◽  
Population Fluctuation ◽  
And Control

Abiotic factors, such as temperature, humidity, soil elements, along with biotic factors affect terrestrial arthropod communities. Since the application of agricultural fertilizers with the entrance of different elements causes changes in the soil physicochemical conditions, fertilizers may cause fluctuation in the population density of edaphic arthropods. Given this opinion, in this research, the effect of common fertilizers on the population fluctuation and distribution pattern of the predatory mite Leitneria pugio (Karg) was investigated. The experimental treatments were granular urea fertilizer with two doses (200 and 400 kg per ha), poultry manure, zinc sludge (to simulate the accumulation of zinc sulfate fertilizer in the soil), and control in five blocks. Humidity, pH, temperature, NO3– and NO2–, and elements (organic Carbon, K, Na, P, Fe, Cu, Pb, Cr, Cd, Ni, Zn, and As) of soil were measured, and their relationship with the predatory mite population was determined by Pearson correlation coefficient. Iwao's patchiness, Taylor's power law, and Morisita's coefficient of dispersion were used for determining the spatial distribution pattern of L. pugio. The spatial pattern of L. pugio was aggregated, and the highest population density of the predator was observed in December in zinc sludge and control treatments, and in May, in zinc sludge treatment, on the average 60, 35, and 110 per m2, respectively. The relationship between mite's population and Cu and Pb was significantly positive, and L. pugio had a significantly negative relationship with P, NO3– and soil temperature. Nevertheless, the application of different fertilizers did not affect the spatial distribution pattern of the predator.

Determination of factors involved in the rejection of bananas (Musa acuminata) intended for international commercialization

2020 ◽  
Keyword(s):  
Management Practices ◽  
Abiotic Factors ◽  
Quality Standards ◽  
Musa Acuminata ◽  
P Value ◽  
Biotic Factors ◽  
Significance Level ◽  
Export Sector ◽  
Export System

The banana agro-export sector in Ecuador provides millions of dollars in income for this concept, but with this development, a series of quality standards have been established that must be met to enter the export system. This has contributed to establishing good post-harvest production and management practices that guarantee the optimal production of bananas and plantains. The objective of this study was to determine the factors involved in the rejection of bananas (Musa acuminata) destined for international commercialization. The methodology considered the design modality of non-experimental transactional research, with a quantitative approach. The methodological design was developed in three phases at Finca 6 Hermanas located in the Barraganete sector of the San Juan parish in the Puebloviejo canton of the Los Ríos Province, Ecuador. The results highlight that the main causes for which banana rejection is generated are due to abiotic factors (damage, dry latex, scar, insect damage, broken neck, overgrowth) in a higher percentage of 79.55 % and biotic factors ( twins, diseases, short finger) by 20.45 %. The average rejection was 6 361 fingers and1 269 Kilograms (K) over the 6-week study duration. The analysis of variance turned out to be significant for variable 1 (biotic and abiotic). Ho is rejected; with the criterion of p-value < 0.0001 and F (9; 45) = 2.10., F = 13.17> F critic. In the case of variable (2) “work weeks”, Ho is accepted with the criteria obtained of p-value of 0.7694 and F (5; 45) = 2.4., As F = 0.51 < F critic, it is concludes, that with a significance level of 5% the null hypothesis is accepted. It is concluded that these figures lead to the elaboration of strategies that systemically mitigate the damages, by correcting each one of the causes that cause the deterioration of the banana and increasing the economic gains of the commercialization process.

scholarly journals Advantages and potential challenges of data management in e-maintenance

2019 ◽  
Vol 25 (3) ◽  
pp. 378-396 ◽  
Author(s):  
Arian Razmi-Farooji ◽  
Hanna Kropsu-Vehkaperä ◽  
Janne Härkönen ◽  
Harri Haapasalo
Keyword(s):  
Data Management ◽  
Design Methodology ◽  
Management Practices ◽  
Future Research ◽  
Conceptual Approach ◽  
Content Type ◽  
Different Types ◽  
Maintenance Systems ◽  
Industry Leader ◽  
Practical Implications

Purpose The purpose of this paper is twofold: first, to understand data management challenges in e-maintenance systems from a holistically viewpoint through summarizing the earlier scattered research in the field, and second, to present a conceptual approach for addressing these challenges in practice. Design/methodology/approach The study is realized as a combination of a literature review and by the means of analyzing the practices on an industry leader in manufacturing and maintenance services. Findings This research provides a general understanding over data management challenges in e-maintenance and summarizes their associated proposed solutions. In addition, this paper lists and exemplifies different types and sources of data which can be collected in e-maintenance, across different organizational levels. Analyzing the data management practices of an e-maintenance industry leader provides a conceptual approach to address identified challenges in practice. Research limitations/implications Since this paper is based on studying the practices of a single company, it might be limited to generalize the results. Future research topics can focus on each of mentioned data management challenges and also validate the applicability of presented model in other companies and industries. Practical implications Understanding the e-maintenance-related challenges helps maintenance managers and other involved stakeholders in e-maintenance systems to better solve the challenges. Originality/value The so-far literature on e-maintenance has been studied with narrow focus to data and data management in e-maintenance appears as one of the less studied topics in the literature. This research paper contributes to e-maintenance by highlighting the deficiencies of the discussion surrounding the perspectives of data management in e-maintenance by studying all common data management challenges and listing different types of data which need to be acquired in e-maintenance systems.

scholarly journals Organizational Commitment and Lean Sustainability: Literature Review and Directions for Future Research

2021 ◽  
Vol 13 (6) ◽  
pp. 3357 ◽  
Author(s):  
Amal Benkarim ◽  
Daniel Imbeau
Keyword(s):  
Organizational Commitment ◽  
Literature Review ◽  
Lean Manufacturing ◽  
Affective Commitment ◽  
Management Practices ◽  
Employee Commitment ◽  
Future Research ◽  
Comprehensive Overview ◽  
Narrative Literature Review ◽  
Key Aspects

The vast majority of works published on Lean focus on the evaluation of tools and/or the strategies needed for its implementation. Although many authors highlight the degree of employee commitment as one of the key aspects of Lean, what has gone largely unnoticed in the literature, is that few studies have examined in-depth the concept of organizational commitment in connection with Lean. With this narrative literature review article, our main objective is (1) to identify and analyze an extensive body of literature that addresses the Lean Manufacturing approach and how it relates to employee commitment, emphasizing affective commitment as the main type of organizational commitment positively associated with Lean, and (2) to highlight the management practices required to encourage this kind of commitment and promote the success and sustainability of Lean. This paper aims to provide a comprehensive overview that can help researchers and practitioners interested in Lean better understand the importance of employee commitment in this type of approach, and as well, to identify related research questions.

Earnings management and equity incentives: evidence from the European banking industry

2019 ◽  
Vol 27 (2) ◽  
pp. 244-261 ◽  
Author(s):  
Mohammad Alhadab ◽  
Bassam Al-Own
Keyword(s):  
Earnings Management ◽  
Management Practices ◽  
Banking Industry ◽  
Future Research ◽  
Loan Loss ◽  
Content Type ◽  
Loan Loss Provisions ◽  
Equity Incentives ◽  
European Banking ◽  
European Banks

Purpose This study aims to examine the effect of equity incentives on earnings management that occurs via the use of loan loss provisions by using a sample of 204 bank-year observations over the period 2006-2011. Design/methodology/approach The authors use the data of 39 European banks to test the main hypothesis. Several valuation models and regressions are used to measure the main proxies for executives’ compensation and the determinant factors of loan loss provisions. Findings The empirical results reveal that earnings management that occurs via discretionary loan loss provisions is associated with equity incentives in the banking industry. In particular, European banks’ executives with high equity incentives are found to manage reported earnings upwards by reducing loan loss provisions. The results therefore show that income-increasing earnings management via discretionary loan loss provisions is widely practised by the executives of European banks and that this is partly motivated by executives’ compensation. Practical implications The findings of this paper present important implications for regulators in the European Union, who should take further steps to reform the regulatory environment to monitor and mitigate the earnings management practices that occur via the manipulation of loan loss provisions. Earnings management practices do not just negatively affect subsequent performance but are also found to lead to firms’ failure. Thus, regulators should take the necessary reforms to protect the wealth of stakeholders (investors, creditors, etc.). Originality/value This study provides the first evidence on the relationship between equity incentives and earnings management in the European banking industry. The study sheds more light on an issue of great interest to a broad audience that does not receive much attention in the prior research, thus opening new avenues for future research.

scholarly journals Biotic and Abiotic Factors Influencing Arsenic Biogeochemistry and Toxicity in Fluvial Ecosystems: A Review

2020 ◽  
Vol 17 (7) ◽  
pp. 2331
Author(s):  
Laura Barral-Fraga ◽  
María Teresa Barral ◽  
Keeley L. MacNeill ◽  
Diego Martiñá-Prieto ◽  
Soizic Morin ◽  
...  
Keyword(s):  
Abiotic Factors ◽  
Arsenic Exposure ◽  
Inorganic Arsenic ◽  
Future Research ◽  
Strong Impact ◽  
Trophic Relations ◽  
Fluvial Systems ◽  
Pampean Streams ◽  
Micro Organisms ◽  
Different Origins

This review is focused on the biogeochemistry of arsenic in freshwaters and, especially, on the key role that benthic microalgae and prokaryotic communities from biofilms play together in through speciation, distribution, and cycling. These microorganisms incorporate the dominant iAs (inorganic arsenic) form and may transform it to other arsenic forms through metabolic or detoxifying processes. These transformations have a big impact on the environmental behavior of arsenic because different chemical forms exhibit differences in mobility and toxicity. Moreover, exposure to toxicants may alter the physiology and structure of biofilms, leading to changes in ecosystem function and trophic relations. In this review we also explain how microorganisms (i.e., biofilms) can influence the effects of arsenic exposure on other key constituents of aquatic ecosystems such as fish. At the end, we present two real cases of fluvial systems with different origins of arsenic exposure (natural vs. anthropogenic) that have improved our comprehension of arsenic biogeochemistry and toxicity in freshwaters, the Pampean streams (Argentina) and the Anllóns River (Galicia, Spain). We finish with a briefly discussion of what we consider as future research needs on this topic. This work especially contributes to the general understanding of biofilms influencing arsenic biogeochemistry and highlights the strong impact of nutrient availability on arsenic toxicity for freshwater (micro) organisms.

Risk assessment of waterborne protozoa: current status and future trends

Parasitology ◽  
1999 ◽  
Vol 117 (7) ◽  
pp. 205-212 ◽  
Author(s):  
C. J. GIBSON ◽  
C. N. HAAS ◽  
J. B. ROSE
Keyword(s):  
Risk Assessment ◽  
Management Practices ◽  
Assessment Methods ◽  
Detection Methods ◽  
Current Status ◽  
Future Research ◽  
Microbial Risk Assessment ◽  
Microbial Risk ◽  
Chemical Risk Assessment ◽  
Low Levels

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.

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 Quinoa’s Potential to Enhance Dietary Management of Obesity and Type-2 Diabetes: A Review of the Current Evidence

Diabetology ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 77-94
Author(s):  
Alexander Little ◽  
Kevin Murphy ◽  
Patrick Solverson
Keyword(s):  
Type 2 Diabetes ◽  
Best Management Practices ◽  
Management Practices ◽  
The United States ◽  
Lipid Absorption ◽  
Current Evidence ◽  
Future Research ◽  
Dietary Management ◽  
Obesity And Diabetes

The prevalence of diet-induced obesity and type-2 diabetes remains a growing concern in the United States. As best management practices still include improved diet and physical activity, bioactive food components, contained within functional foods, show promise in curbing the cardiometabolic complications associated with excess weight and diabetes. Quinoa is an emerging candidate crop for its versatility in wide-ranging growing conditions as one approach to address food security, but it also contains several components that may serve as a dietary tool for post-industrial countries struggling with the health complications of caloric excess. Preliminary rodent feeding studies demonstrate that components within quinoa, namely, phytosteroids, phenolics, polysaccharides, and peptides, can prevent adiposity, dyslipidemia, and hyperglycemia. Mechanistic activity may involve reduced lipid absorption and adipogenesis, increased energy expenditure and glucose oxidation and corrected gut microbiota. Other intestinal actions may include blocked carbohydrate digestion with enhanced incretin signaling. Evidence in clinical trials is lacking and future research spanning cells to the clinic is needed to further elucidate the interesting preliminary reports reviewed here. Quinoa offers several unique attributes that could be harnessed to improve the dietary management of obesity and diabetes.

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