scholarly journals The relationship between natural rain intensity and Ascochyta blight in chickpea development.

2021 ◽  
Author(s):  
Ihsanul Khaliq ◽  
Kevin Moore ◽  
Adam H. Sparks
Keyword(s):  
Wind Speed ◽  
Ascochyta Blight ◽  
Soil Surface ◽  
Rainfall Event ◽  
Rain Intensity ◽  
Plant Parts ◽  
Negative Effect ◽  
Trap Plants ◽  
Rain Events ◽  
The Relationship

Abstract Ascochyta blight is one of the most devastating diseases of chickpea worldwide. In Australia, Ascochyta blight management strategy in a standing crop is solely based on applying protective fungicides before a forecast rainfall event. Despite this, studies on the likely interaction between variable natural rain amount, rain duration, environmental factors and Ascochyta blight development are rare. We used generalised linear mixed models to investigate the relationship between rain intensity, wind speed and Ascochyta blight development. Briefly, 7 g of infested chickpea residue were placed at the soil surface in a 1 m2 plot, and three pots (3 trap plants per pot) of a susceptible chickpea cultivar were randomly placed on each side of the 1 m2 plot (total 12 pots), preceding a forecast rainfall event. Trap plants were transferred to a controlled temperature room (20°C) for 48 h (100% humidity) after rain events. After a 48 h incubation period, trap plants were transferred to a glasshouse (20°C) to allow lesion development. The number of lesions on all plant parts were counted after two weeks. Lesions developed in rain amounts as low as 1.4 mm and rain durations as short as 0.7 h. The number of lesions significantly increased with increasing rain amount. There was positive effect of increasing rain duration and a negative effect of increasing wind speed. This study suggests that small rain amounts, shorter duration rains or a limited amount of primary inoculum are not barriers to conidial dispersal or infection.

scholarly journals Wind Speed Effects on the Quantity of Xanthomonas citri subsp. citri Dispersed Downwind from Canopies of Grapefruit Trees Infected with Citrus Canker

Plant Disease ◽  
2010 ◽  
Vol 94 (6) ◽  
pp. 725-736 ◽  
Author(s):  
C. H. Bock ◽  
J. H. Graham ◽  
T. R. Gottwald ◽  
A. Z. Cook ◽  
P. E. Parker
Keyword(s):  
Wind Speed ◽  
Ground Level ◽  
Citrus Canker ◽  
Disease Spread ◽  
Xanthomonas Citri ◽  
Wind Speeds ◽  
Speed Up ◽  
The Mean ◽  
Rain Events ◽  
The Relationship

The epidemic of citrus canker (Xanthomonas citri subsp. citri) in Florida continues to expand since termination of the eradication program in 2006. Storms are known to be associated with disease spread, but little information exists on the interaction of fundamental physical and biological processes involved in dispersal of this bacterium. To investigate the role of wind speed in dispersal, wind/rain events were simulated using a fan to generate wind up to 19 m·s-1 and spray nozzles to simulate rain. Funnels at ground level and panels at 1.3 m height and distances up to 5 m downwind collected wind-driven splash. Greater wind speeds consistently dispersed more bacteria, measured by concentration (colony forming units [CFU] ml-1) or number sampled (bacteria flux density [BFD] = bacteria cm-2 min-1), from the canopy in the splash. The CFU ml-1 of X. citri subsp. citri collected by panels 1 m downwind at the highest wind speed was up to 41-fold greater than that collected at the lowest wind speed. BFD at the highest wind speed was up to 884-fold higher than that collected at the lowest wind speed. Both panels at distances >1 m and funnels at distances >0 m collected many-fold more X. citri subsp. citri at higher wind speeds compared to no wind (up to 1.4 × 103-fold greater CFU ml-1 and 1.8 × 105-fold the BFD). The resulting relationship between wind speed up to 19 m·s-1 and the mean CFU ml-1 collected by panel collectors downwind was linear and highly significant. Likewise, the mean CFU ml-1 collected from the funnel collectors had a linear relationship with wind speed. The relationship between wind speed and BFD collected by panels was generally similar to that described for CFU ml-1 of X. citri subsp. citri collected. However, BFD collected by funnels was too inconsistent to determine a meaningful relationship with increasing wind speed. The quantity of bacteria collected by panels declined with distance, and the relationship was described by an inverse power model (R2 = 0.94 to 1.00). At higher wind speeds, more bacteria were dispersed to all distances. Windborne inoculum in splash in subtropical wet environments is likely to be epidemiologically significant, as both rain intensity and high wind speed can interact to provide conditions conducive for dispersing large quantities of bacteria from canker-infected citrus trees. Disease and crop management aimed at reducing sources of inoculum and wind speeds in a grove should help minimize disease spread by windborne inoculum.

scholarly journals Impact of climate and governments measures on COVID-19 spread : Evidence from data

2021 ◽  
Author(s):  
Kassimou Abdoul Haki Maoude ◽  
Chaffa Odjouwoni Lucien Chaffa ◽  
Idossou Marius Adom
Keyword(s):  
Wind Speed ◽  
Threshold Effect ◽  
Sir Model ◽  
Effect Of Temperature ◽  
Lower Growth ◽  
Average Temperature ◽  
Negative Effect ◽  
The One ◽  
The Relationship ◽  
Positive Effect

Abstract This paper investigates the effects of climate and governments responses on the spread of the COVID-19. Our strategy is empirical. Our model is based on an accounting equation derived from the SIR model, and estimates the relationship between the growth of the daily COVID-19 confirmed cases on the one hand, and climatic variables (such as the daily average temperature and the wind speed) and governments responses to COVID-19 on the other hand. We also develop a theoretical approach to test the presence of a threshold in the effect of the temperature on the COVID-19 spread. Using a panel data on a sample of 294 territories overs 106 days (from 22 January, 2020 to 06 May, 2020), we find significant negative effect of temperature and temperature variability and significant positive effect of wind speed and precipitation on the growth of the COVID-19 confirmed cases. We also find that governments responses are associated to a lower growth of confirmed cases. But we do not find any universally applicable threshold effect in the relationship between the average temperature and the confirmed cases growth.JEL Classification: C12, C15, C23, C60

scholarly journals The impact of weather on COVID-19 pandemic

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Michael Ganslmeier ◽  
Davide Furceri ◽  
Jonathan D. Ostry
Keyword(s):  
Wind Speed ◽  
Herd Immunity ◽  
High Mobility ◽  
Confounding Factors ◽  
Virus Spread ◽  
Containment Measures ◽  
Negative Effect ◽  
Temperature Levels ◽  
The Impact ◽  
The Relationship

AbstractRising temperature levels during spring and summer are often argued to enable lifting of strict containment measures even in the absence of herd immunity. Despite broad scholarly interest in the relationship between weather and coronavirus spread, previous studies come to very mixed results. To contribute to this puzzle, the paper examines the impact of weather on the COVID-19 pandemic using a unique granular dataset of over 1.2 million daily observations covering over 3700 counties in nine countries for all seasons of 2020. Our results show that temperature and wind speed have a robust negative effect on virus spread after controlling for a range of potential confounding factors. These effects, however, are substantially larger during mealtimes, as well as in periods of high mobility and low containment, suggesting an important role for social behaviour.

The relationship of number and position of seeds to fruit size and curvature in Capsicum annuum L.

1984 ◽  
Vol 102 (2) ◽  
pp. 509-510
Author(s):  
R. N. McArdle
Keyword(s):  
Capsicum Annuum ◽  
Fruit Size ◽  
Soil Surface ◽  
Fruit Growth ◽  
Plant Parts ◽  
Capsicum Annuum L ◽  
Physical Barriers ◽  
Relationship Of ◽  
The Relationship

Fruit curvature is a trait which has been little investigated by botanists and horticulturists. The degree to which a fruit is curved can be accounted for intuitively in cases where there are no physical barriers to normal fruit growth, such as obstruction by plant parts or the soil surface. The curvature of pendant, unobstructed fruit, as in the Solanaceae, has received limited discussion in the literature.

The Impact of Competitive Quasi-Market on Service Delivery in Benue State University, Makurdi Nigeria

GIS Business ◽  
2019 ◽  
Vol 14 (4) ◽  
pp. 85-98
Author(s):  
Idoko Peter
Keyword(s):  
Service Delivery ◽  
A Priori ◽  
Least Square ◽  
Secondary Source ◽  
State University ◽  
Ordinary Least Square ◽  
Negative Effect ◽  
The Impact ◽  
The Relationship

This research the impact of competitive quasi market on service delivery in Benue State University, Makurdi Nigeria. Both primary and secondary source of data and information were used for the study and questionnaire was used to extract information from the purposively selected respondents. The population for this study is one hundred and seventy three (173) administrative staff of Benue State University selected at random. The statistical tools employed was the classical ordinary least square (OLS) and the probability value of the estimates was used to tests hypotheses of the study. The result of the study indicates that a positive relationship exist between Competitive quasi marketing in Benue State University, Makurdi Nigeria (CQM) and Transparency in the service delivery (TRSP) and the relationship is statistically significant (p<0.05). Competitive quasi marketing (CQM) has a negative effect on Observe Competence in Benue State University, Makurdi Nigeria (OBCP) and the relationship is not statistically significant (p>0.05). Competitive quasi marketing (CQM) has a positive effect on Innovation in Benue State University, Makurdi Nigeria (INVO) and the relationship is statistically significant (p<0.05) and in line with a priori expectation. This means that a unit increases in Competitive quasi marketing (CQM) will result to a corresponding increase in innovation in Benue State University, Makurdi Nigeria (INVO) by a margin of 22.5%. It was concluded that government monopoly in the provision of certain types of services has greatly affected the quality of service experience in the institution. It was recommended among others that the stakeholders in the market has to be transparent so that the system will be productive to serve the society effectively

Adolescent smoking behavior and communication with parents: Depression as a mediator and gender as a moderator

2019 ◽  
Vol 47 (10) ◽  
pp. 1-9 ◽  
Author(s):  
Xieping Chen ◽  
Qian Xie ◽  
Yuting Yang
Keyword(s):  
Smoking Behavior ◽  
Depression Scale ◽  
Epidemiological Studies ◽  
Adolescent Smoking ◽  
Junior High Schools ◽  
Test Results ◽  
Negative Effect ◽  
And Gender ◽  
The Relationship ◽  
Communication Scale

Parent–adolescent communication is assumed to be an important factor affecting adolescent smoking behavior. However, the inner mechanism accounting for this association has still not been clarified in research. Our purpose in this study was to examine the relationships between parent–adolescent communication, adolescent smoking behavior, and depression, as well as gender differences in the relationship between depression and adolescent smoking behavior. Participants were 1,134 students at 6 junior high schools in China who completed the Parent-Adolescent Communication Scale, the Epidemiological Studies Depression Scale, and the Smoking Behavior Test. Results showed that parent-adolescent communication had a significant negative effect on adolescent smoking behavior and depression partially mediated the relationship between parent–adolescent communication and adolescent smoking behavior. In addition, gender moderated the relationship between depression and adolescent smoking behavior. Overall, these findings may help to promote better understanding of the relationship between parent–adolescent communication and adolescent smoking behavior.

scholarly journals Coal Fly Ash and Polyacrylamide Influence Transport and Redistribution of Soil Nitrogen in a Sandy Sloping Land

Agriculture ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 47
Author(s):  
Kai Yang ◽  
Zejun Tang ◽  
Jianzhang Feng
Keyword(s):  
Fly Ash ◽  
Sandy Soil ◽  
Coal Fly Ash ◽  
Soil Layer ◽  
Nutrient Retention ◽  
Soil Surface ◽  
Rainfall Event ◽  
N Losses ◽  
N Concentration ◽  
Application Rates

Sandy soils are prone to nutrient losses, and consequently do not have as much as agricultural productivity as other soils. In this study, coal fly ash (CFA) and anionic polyacrylamide (PAM) granules were used as a sandy soil amendment. The two additives were incorporated to the sandy soil layer (depth of 0.2 m, slope gradient of 10°) at three CFA dosages and two PAM dosages. Urea was applied uniformly onto the low-nitrogen (N) soil surface prior to the simulated rainfall experiment (rainfall intensity of 1.5 mm/min). The results showed that compared with no addition of CFA and PAM, the addition of CFA and/or PAM caused some increases in the cumulative NO3−-N and NH4+-N losses with surface runoff; when the rainfall event ended, 15% CFA alone treatment and 0.01–0.02% PAM alone treatment resulted in small but significant increases in the cumulative runoff-associated NO3−-N concentration (p < 0.05), meanwhile 10% CFA + 0.01% PAM treatment and 15% CFA alone treatment resulted in nonsignificant small increases in the cumulative runoff-associated NH4+-N concentration (p > 0.05). After the rainfall event, both CFA and PAM alone treatments increased the concentrations of NO3−-N and NH4+-N retained in the sandy soil layer compared with the unamended soil. As the CFA and PAM co-application rates increased, the additive effect of CFA and PAM on improving the nutrient retention of sandy soil increased.

Will rivals enter or wait outside when faced with litigation risk? Patent litigation in complex product industries and international market entry

2021 ◽  
pp. 147612702199825
Author(s):  
Ergun Onoz ◽  
Claudio Giachetti
Keyword(s):  
Market Entry ◽  
International Market ◽  
Joint Effect ◽  
Litigation Risk ◽  
Patent Litigation ◽  
Complex Product ◽  
Patent Strategy ◽  
Negative Effect ◽  
Rival Firms ◽  
The Relationship

A spiral of patent infringement litigation among rival firms is a phenomenon often observed in complex product industries, where products comprise numerous separately patentable elements. Theoretically grounded in the awareness–motivation–capability framework of competitive dynamics, this article contributes to the literature on patent strategy and international market entry by looking at how, in a complex product industry, the intensity of patent litigation in a country affects a firm’s decision to enter that country. Our results show that the intensity of patent litigation in a country is a deterrent for potential entrants and has a negative effect on a firm’s likelihood of entering that country. We also show that a firm’s previous experience with patent litigation ( awareness component), the share of a firm’s current patent applications in a target country ( motivation component), and the size of a firm’s patent stock ( capability component) moderate the relationship between a country’s patent litigation intensity and a firm’s likelihood of entering that country. We thus shed light on the joint effect of macro- and micro-level patent-related variables on a firm’s market entry decisions. We test our hypotheses with a comprehensive panel of patenting and entry strategies of 84 mobile phone vendors and their patent litigation battles in 45 countries, from 2003 to 2015.

scholarly journals Relationships Among the Feeding Behaviors of a Mirid Bug on Cotton Leaves of Different Ages and Plant Biochemical Substances

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Haiyan Song ◽  
Zhaoke Dong ◽  
Lili Li ◽  
Zengbin Lu ◽  
Chao Li ◽  
...  
Keyword(s):  
Negative Impact ◽  
Leaf Age ◽  
Leaf Traits ◽  
Cotton Leaf ◽  
Young Plant ◽  
Feeding Behaviors ◽  
Probing Behavior ◽  
Negative Effect ◽  
Mirid Bug ◽  
The Relationship

Abstract Apolygus lucorum (Meyer-Dür) (Hemiptera: Miridae) tends to feed on young plant tissues. To explore the relationship between stylet probing behaviors of adult A. lucorum and conditions of cotton leaves, we conducted an experiment using electropenetrography (EPG). Behaviors were recorded on four cotton varieties, in relation to thickness and biochemical traits of differently-aged leaves. Cotton leaf age had a significant effect on the probing behavior of A. lucorum but cotton variety did not. One-day-old leaves of A. lucorum received the highest mean number of stylet probes (penetrations) per insect, and longest mean durations per insect of combined stylet probing or its components, cell rupture and ingestion behaviors. All of the leaf traits (thickness and biochemical substances) were similar among these four cotton varieties. Leaf thickness had a significantly negative effect on the same four variables above. Gossypol and tannin also had a negative impact on combined probing duration. Redundancy analysis showed that the four EPG variables were closely related to nutrient substances (amino acids, sugar, and water) while they had the opposite relationship with plant defense substances (gossypol and tannin). On cotton in the seedling stages, A. lucorum fed more readily on the youngest, thinnest leaves in our no-choice EPG experiments. Nutrients and chemical resistance substances determined the probing duration of A. lucorum. Our findings can contribute to better understanding of patterns of feeding and host consumption by A. lucorum, ultimately improving cotton resistance to A. lucorum.

A Preliminary Test of the Impact of De-Globalization on MNC Performance

2021 ◽  
Vol 17 (2) ◽  
pp. 412-428
Author(s):  
Hilla Peretz ◽  
Michael J. Morley
Keyword(s):  
Organizational Context ◽  
Preliminary Test ◽  
Organizational Level ◽  
Institutional Fit ◽  
Preliminary Examination ◽  
Negative Effect ◽  
Key Dimensions ◽  
Using Data ◽  
The Impact ◽  
The Relationship

ABSTRACTWe offer a preliminary examination of whether national and organizational level contexts amplify or reduce the effects of de-globalization on the performance of MNCs. Theoretically, we borrow ideas from both event system theory and institutional fit to propose a model explicating key dimensions of the relationship between de-globalization, national and organizational context, and MNC performance. We then test our ideas using data assembled from 283 MNCs in 20 countries. We find that while de-globalization has a negative effect on MNC performance, national and organizational level contextual endowments do moderate this relationship. We discuss some implications of our findings and highlight attendant limitations.

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