Direct and indirect effects of plant litter on a seed–pathogen interaction inBromus tectorumseed banks

2011 ◽  
Vol 22 (2) ◽  
pp. 135-144 ◽  
Author(s):  
Julie Beckstead ◽  
Lauren E. Miller ◽  
Brian M. Connolly
Keyword(s):  
Seed Bank ◽  
Disease Transmission ◽  
Indirect Effects ◽  
Early Summer ◽  
Plant Litter ◽  
Arid Environments ◽  
Direct And Indirect Effects ◽  
Seed Mortality ◽  
Ecological Importance

AbstractThe naturally occurring fungal seed pathogen,Pyrenophora semeniperda, reduces the seed bank ofBromus tectorumbut the role of plant litter in this seed–pathogen interaction is unexplored. To investigate the direct and indirect effects of litter on this interaction, we first collected field seed-bank samples from low and highBromuslitter patches. From these data, we explored the relationship between litter depth, seed-bank density and seed mortality fromP. semeniperda. Second, we manipulated the fungal stages (conidial spores and mycelium) in/on the litter through sterilization techniques, to measure the direct effect of litter on seed death. Third, for indirect effects, we manipulated litter levels and held seed density and inoculum constant to determine whetherBromuslitter could modify the seed zone microsites to favour disease. We found that seed-bank samples from high-litter patches contained higher field-killed seed densities compared with low-litter patches, although the percent difference of disease between litter patch types varied among sites and years (e.g. 80% to 46%). In testing the direct effects of litter on the seed–pathogen interaction, we found that litter can act as a direct inoculum source for the pathogen in the early summer but decreases in disease transmission by the following spring when the litter naturally is in contact with seeds. Investigating indirect effects, we found four times as many pathogen-killed seeds in high-litter treatments as compared with low-litter treatments when inoculum loads and seed densities were held constant. In addition, we found that litter influences the seed–pathogen interaction through density-dependent disease transmission. Our findings demonstrate the ecological importance of litter in semi-arid environments as it influences disease levels of a seed pathogen by direct and indirect means.

The role of soil temperature and seed dormancy in the creation and maintenance of persistent seed banks of Nassella trichotoma (serrated tussock) on the Northern Tablelands of New South Wales

2020 ◽  
Vol 42 (2) ◽  
pp. 85
Author(s):  
Annemieke Ruttledge ◽  
Ralph D. B. Whalley ◽  
Gregory Falzon ◽  
David Backhouse ◽  
Brian M. Sindel
Keyword(s):  
Seed Bank ◽  
New South ◽  
Soil Seed Bank ◽  
Seed Banks ◽  
Early Summer ◽  
Secondary Dormancy ◽  
South Wales ◽  
The Creation ◽  
Persistent Soil Seed Bank

A large and persistent soil seed bank characterises many important grass weeds, including Nassella trichotoma (Nees) Hack. ex Arechav. (serrated tussock), a major weed in Australia and other countries. In the present study we examined the effects of constant and alternating temperatures in regulating primary and secondary dormancy and the creation and maintenance of its soil seed bank in northern NSW, Australia. One-month-old seeds were stored at 4, 25°C, 40/10°C and 40°C, in a laboratory, and germination tests were conducted every two weeks. Few seeds germinated following storage at 4°C, compared with seeds stored at 25°C, 40/10°C and 40°C. Nylon bags containing freshly harvested seeds were buried among N. trichotoma stands in early summer, and germination tests conducted following exhumation after each season over the next 12 months. Seeds buried over summer and summer plus autumn had higher germination than seeds buried over summer plus autumn plus winter, but germination increased again in the subsequent spring. Seeds stored for zero, three, six and 12 months at laboratory temperatures were placed on a thermogradient plate with 81 temperature combinations, followed by incubation at constant 25°C of un-germinated seeds. Constant high or low temperatures prolonged primary dormancy or induced secondary dormancy whereas alternating temperatures tended to break dormancy. Few temperature combinations resulted in more than 80% germination.

scholarly journals Antecedents and Implications of Innovation Capability: Empirical Study of Bakpia MSMEs in Yogyakarta

2021 ◽  
Vol 36 (2) ◽  
pp. 179-203
Author(s):  
Baroroh Nurhayati ◽  
Titik Kusmantini ◽  
Tri Wahyuningsih
Keyword(s):  
Indirect Effects ◽  
Innovation Performance ◽  
Direct And Indirect Effects ◽  
Innovation Capability ◽  
Tourist Attractions ◽  
Tourism Sector ◽  
Food And Beverage ◽  
Main Driver ◽  
Performance Research

Introduction/Main Objectives: This research examines the antecedents and implications of innovation capability, empirically. The outcomes aim at contributing to the knowledge and understanding about the main driver of innovation capability.  Background Problems: Yogyakarta is known for its many and varied charms, its tourist attractions, the availability of facilities and infrastructure to support tourism, such as souvenir sellers. But there is known that number of total foreign and domestic tourists has been a decrease in 2018 (Semester I by 11.51% and II by 3.33%), also in 2019 (Semester I by 11.23%). This is a challenge for MSMEs in the tourism sector and MSMEs in other sectors that support tourism, such a souvenir seller. Bakpia is one of the well-known products of the food and beverage sector in Yogyakarta often bought for souvenirs. The Bakpia MSMEs’ innovations were triggered by competition among the Bakpia producers in Yogyakarta. Therefore, every Bakpia MSME must be competitive to survive in the market. Thus, there is a need to improve their innovation capability, which will impact the innovation performance of the Bakpia MSMEs in Yogyakarta. There is a gap in the research regarding the influence of the factors that are predicted to build innovation capability. Novelty: Previous studies’ results indicate that the influence of knowledge donating and knowledge collecting about innovation performance is not yet conclusive. Therefore, this study aims to fill the gap in the previous research by examining the role of capability as a mediating between knowledge sharing process (knowledge donating and knowledge collecting) to innovation performance. Research Methods: Forty-eight items of data were obtained from Bakpia MSMEs in Yogyakarta through a survey conducted by distributing questionnaires directly to them. The data were analyzed using PLS-SEM via SmartPLS version 3.3.2. Findings/Results: This study shows that the direct and indirect effects of sharing knowledge (which includes donating and collecting knowledge) about innovation performance are found to be positive but not significant. The results also indicate that innovation capability does not significantly mediate knowledge donating and knowledge collecting about innovation performance. Meanwhile, the influence of innovation capability on innovation performance was found to be positive and significant. Conclusion: The antecedents are insignificant for innovation capability, but the antecedent’s constructs still act as a driver to build innovation capability.

scholarly journals Climate variability and international migration: an empirical analysis

2015 ◽  
Vol 20 (4) ◽  
pp. 434-468 ◽  
Author(s):  
Nicola D. Coniglio ◽  
Giovanni Pesce
Keyword(s):  
Developing Countries ◽  
International Migration ◽  
Indirect Effects ◽  
Adaptation Strategy ◽  
Seasonal Effects ◽  
Direct And Indirect Effects ◽  
Type Size ◽  
Migration Flows ◽  
Rich Countries

AbstractIs international migration an adaptation strategy to sudden or gradual climatic shocks? In this paper we investigate the direct and the indirect role of climatic shocks in developing countries as a determinant of out-migration flows toward rich OECD countries in the period 1990–2001. Contrarily to the bulk of existing studies, we use a macro approach and explicitly consider the heterogeneity of climatic shocks (type, size, sign of shocks and seasonal effects). Our results show that the occurrence of adverse climatic events in origin countries has significative direct and indirect effects on out-migration from poor to rich countries.

Direct and indirect effects of long-term fertilization on the stability of the persistent seed bank

2019 ◽  
Vol 438 (1-2) ◽  
pp. 239-250 ◽  
Author(s):  
Chunhui Zhang ◽  
Charles G. Willis ◽  
Zhen Ma ◽  
Miaojun Ma ◽  
Péter Csontos ◽  
...  
Keyword(s):  
Seed Bank ◽  
Indirect Effects ◽  
Direct And Indirect Effects ◽  
The Stability ◽  
Persistent Seed Bank

scholarly journals Role of Satisfaction in Mediating the Effect of Services Quality on the Customers’ Loyalty in the Village Credit Institutions of Pekraman, Indonesia

2018 ◽  
Vol 4 (2) ◽  
pp. 147-162 ◽  
Author(s):  
Anak Agung Ngurah Gede Sadiartha ◽  
Gusti Ayu Mirah Apsari
Keyword(s):  
Indirect Effects ◽  
Sampling Method ◽  
Services Quality ◽  
Problem Formulation ◽  
Reliability Test ◽  
Direct And Indirect Effects ◽  
Credit Institution ◽  
The Village ◽  
The Relationship

Loyalty is a deep commitment to repurchase a product or service that becomes a preference consistently in the future by repurchasing the same product. The problem formulation in this study is how are the direct and indirect effects of services quality through satisfaction on the consumers’ loyalty.  This study aims to know the direct and indirect effect of services quality through satisfaction on the consumers’ loyalty. The study was conducted by the village credit institution of Pekraman, Tabanan located in Gajah Mada street 107, Tabanan. The number of samples is 94 customers with slovin’s formula and accidental sampling method. The techniques of data collection used were interviews, documentation, literature review and questionnaire. The research instruments used were validity test and reliability test. The technique of data analysis used was path analysis with sobel test. Based on the result of calculation, it showed that the services quality had a positive and significant effect on the customers’ satisfaction in the village credit institution of Pekraman, Tabanan as many as  0,000 < 0,05. Thus, H0 was rejected and H1 was accepted. The customers’ satisfaction had a positive and significant effect on the customers’ loyalty in the village credit institution of Pekraman, Tabanan as many as 0,000 < 0,05. The services quality had a positive and significant effect of the customers’ loyalty in the village credit institution of Pekraman, Tabanan as many as 0,000 < 0,05. Thus, H0 was rejected and H3 was accepted. Based on the result of calculation, it showed that Zcount (5,323)> Z table (1,96). Thus, the customers’ loyalty can mediate the relationship between customers’ services quality and loyalty on the village credit institution of Pekraman, Tabanan. For the services quality, it is needed to improve the services given to the customers. For instance, it is provided the more exciting interest adjusted to the type of savings chosen by the customers so they will feel more satisfied and can develop their loyalty

scholarly journals The Role of Satisfaction in Mediating the Effect of Services Quality on the Customers’ Loyalty in the Village Credit Institution of Pekraman, Tabanan

2019 ◽  
Vol 8 (1) ◽  
pp. 73-89
Author(s):  
Anak Agung Ngurah Gede Sadiartha ◽  
Gusti Ayu Mirah Apsari
Keyword(s):  
Indirect Effects ◽  
Sampling Method ◽  
Services Quality ◽  
Problem Formulation ◽  
Reliability Test ◽  
Direct And Indirect Effects ◽  
Credit Institution ◽  
The Village ◽  
The Relationship

Loyalty is a deep commitment to repurchase a product or service that becomes a preference consistently in the future by repurchasing the same product. The problem formulation in this study is how are the direct and indirect effects of services quality through satisfaction on the consumers’ loyalty.  This study aims to know the direct and indirect effect of services quality through satisfaction on the consumers’ loyalty. The study was conducted by the village credit institution of Pekraman, Tabanan located in Gajah Mada street 107, Tabanan. The number of samples is 94 customers with slovin’s formula and accidental sampling method. The techniques of data collection used were interviews, documentation, literature review and questionnaire. The research instruments used were validity test and reliability test. The technique of data analysis used was path analysis with sobel test. Based on the result of calculation, it showed that the services quality had a positive and significant effect on the customers’ satisfaction in the village credit institution of Pekraman, Tabanan as many as  0,000 < 0,05. Thus, H0 was rejected and H1 was accepted. The customers’ satisfaction had a positive and significant effect on the customers’ loyalty in the village credit institution of Pekraman, Tabanan as many as 0,000 < 0,05. The services quality had a positive and significant effect of the customers’ loyalty in the village credit institution of Pekraman, Tabanan as many as 0,000 < 0,05. Thus, H0 was rejected and H3 was accepted. Based on the result of calculation, it showed that Zcount (5,323)> Z table (1,96). Thus, the customers’ loyalty can mediate the relationship between customers’ services quality and loyalty on the village credit institution of Pekraman, Tabanan. For the services quality, it is needed to improve the services given to the customers. For instance, it is provided the more exciting interest adjusted to the type of savings chosen by the customers so they will feel more satisfied and can develop their loyalty

scholarly journals Hierarchical path analysis of deer responses to direct and indirect effects of climate in northern forest

2007 ◽  
Vol 363 (1501) ◽  
pp. 2357-2366 ◽  
Author(s):  
Atle Mysterud ◽  
Nigel G Yoccoz ◽  
Rolf Langvatn ◽  
Nathalie Pettorelli ◽  
Nils Chr Stenseth
Keyword(s):  
Boreal Forest ◽  
Body Mass ◽  
Indirect Effects ◽  
Red Deer ◽  
Early Summer ◽  
Hierarchical Bayes ◽  
Direct And Indirect Effects ◽  
Direct Effects ◽  
Spring Temperature ◽  
Large Herbivores

A problem in climate studies has been on how to treat causal chains of explanations and both direct and indirect effects. Mammals in strongly seasonal environments of the boreal forest typically lose condition during winter and gain mass (and reproduce) during the summer season when biomass and plant quality peak. Mass decay of large herbivores during winter is due to direct effects of winter weather, such as increased costs of movement, thermoregulation and reduced access to food when snow is deep. Deer condition during summer is thought to be affected mainly indirectly by weather through plants. High spring temperature speeds up plant development, and deep snow can delay phenology in early summer. Current statistical modelling does not take into account these mechanistic pathways. We used hierarchical Bayes modelling to more mechanistically link global climate, local weather and plant phenology to autumn body mass of red deer in Norway. Red deer were much more affected indirectly through trophic interactions. No solid evidence of direct effects of snow depth was found on autumn body mass. We discuss the implications of our results relative to our ability to predict effects of global change on large mammalian herbivores in the boreal forest.

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