An assessment of variation in foothills rough fescue [Festuca campestris (Rydb.)] in southern Alberta

2003 ◽  
Vol 83 (3) ◽  
pp. 541-550 ◽  
Author(s):  
K. W. May ◽  
W. D. Willms ◽  
Z. Mengli ◽  
T. J. Lysyk
Keyword(s):  
Genetic Variability ◽  
Environmental Variability ◽  
Field Trials ◽  
Collection Site ◽  
South Central ◽  
Test Location ◽  
Southern Alberta ◽  
Selected Traits ◽  
And Performance ◽  
Rough Fescue

The genetic diversity of native plants is thought to be an important consideration in the selection of appropriate material for reclamation. Field trials were c onducted in southern Alberta to determine the genetic variability, expressed through phenotypic and performance attributes, of several populations of foothills rough fescue [ Festuca campestris (Rydb.)] found in southern Alberta and south-central British Co lumbia. The objectives of this study were to determine the extent of genetic variability among plants of foothills rough fescue. Sixty-four plants from four populations were sampled in 1992, propagated vegetatively to produce clones for replicated trials a nd planted in four locations in 1993. Eleven plant characteristics, including phenotypic and performance variables, were observed from 1994 to 1997. Since the plants were grown in common environments, variations among them were assumed to be caused by gen etic differences. All variables were affected ( P < 0.05) by collection site and, with a few exceptions, test location, year and their two and three-way interactions. The most important factors specific to our objectives were collection site and its interact ions with test location and year. The rough fescue plants expressed differences ( P < 0.05) among populations for all selected traits but displayed considerable overlap in the range of values for all variables both within and among test sites. Therefore, wh ile the populations may be different, individuals within populations have common attributes that suggest sufficient genetic variability to allow successful establishment over a greater range of environmental variability than present at their origins. Resu lts from a secondary test suggest that selection pressure, induced by grazing, resulted in genotypes that were more winter-hardy. However, this observation needs further validation with a more robust test. Key words:

An assessment of variation in Idaho fescue [Festuca idahoensis (Elmer)] in southern Alberta

2004 ◽  
Vol 84 (4) ◽  
pp. 1077-1084 ◽  
Author(s):  
K. W. May ◽  
W. D. Willms ◽  
Z. Mengli ◽  
T. J. Lysyk
Keyword(s):  
Genetic Variability ◽  
Environmental Variability ◽  
Large Range ◽  
Genetic Selection ◽  
Field Trials ◽  
Grazing Pressure ◽  
Grass Species ◽  
Test Location ◽  
Southern Alberta ◽  
Festuca Idahoensis

Idaho fescue (Festuca idahoensis Elmer) is a native grass species that has attracted interest for use in revegetation, reclamation and other applications. However, there is a serious shortage of commercially available seed and concern that germplasm used will not be adapted to the site. A component of adaptation is genetic variability that allows a species to occupy a greater range of environments. Field trials were conducted in southern Alberta to determine the genetic variability of phenotypic and performance characteristics among genotypes of Idaho fescue. Since grazing pressure may contribute to genetic selection and may therefore affect the variability within a population, we also compared genotypes taken from a heavily grazed paddock with those taken from a lightly grazed paddock. Forty-nine genotypes from three populations were randomly sampled in 1992, propagated vegetatively to produce plants for replicated trials and planted in four locations in 1993. Nine plant characteristics were observed from 1993 to 1997. Since the genotypes were grown in common environments, variation among them was assumed to be caused by genetic differences. All variables were affected (P < 0.05) by population, test location and year, while the effect of population was also influenced by test location and year for a few variables. While the Idaho fescue plants expressed differences (P < 0.05) among populations for all selected traits, they displayed considerable overlap in the range of values for all variables both within and among test locations. Therefore, while the populations may be different, individuals within populations exhibit common attributes over a large range. This suggests that sufficient genetic variability exists in all populations to allow successful establishment over a large range of environmental variability. Results from a secondary test suggest that selection pressure, induced by grazing, resulted in genotypes that were smaller in crown circumference, had less spring vigor, had shorter flowering tillers and produced less seed. However, this observation needs further validation with a more robust test. Key words: Morphology, genotypes, seed yield, winter kill, grazing response

scholarly journals Performance of Half-Sib Progenies Developed from an Early Maturing Maize (Zea mays L.) Population in a Rain-Forest Location

2020 ◽  
pp. 58-68
Author(s):  
A. O. Fadahunsi ◽  
A. Oluwaranti ◽  
M. A. B. Fakorede
Keyword(s):  
Crop Production ◽  
Block Design ◽  
Field Trials ◽  
Maize Breeding ◽  
Late Planting ◽  
Maize Population ◽  
Significant Difference ◽  
Early Maturing ◽  
Selected Traits ◽  
And Performance

Problem: Half-sib progenies were developed in a maize breeding program of the Department of Crop Production and Protection of Obafemi Awolowo University Ile-Ife, Nigeria but have not been evaluated for further improvements. Aims: Therefore, this study was undertaken to evaluate the performances of the half-sib progenies, as well as estimate and determine the association among selected traits. Study Design: 160 half-sib progenies each developed in the late planting seasons of 2013 and 2014 from an early maturing maize population were used for this study. Each of the field trials were laid out in a 16 x 10 incomplete block design and replicated twice. Place and Duration of Study: The study was conducted during the early and late planting seasons of 2015 at the Teaching and Research Farm, Obafemi Awolowo University, Ile-Ife (7º28’N 4º33’E and 244 m above sea level). Methodology: All data collected were subjected to Analysis of Variance (ANOVA) and means were separated using Least Significant Difference (LSD) at 0.05 probability level. Genotypic and phenotypic variances were generated to calculate heritability estimates for all traits taken. Results: The results observed showed highly significant differences (P < 0.01) between seasons and among half-sib progenies from both years of development for all traits. Half-sib progenies developed in 2014 were also observed to perform better than those developed in 2013 for all traits studied. Heritability was high (72%) for ear height for the 2013 developed half-sib progenies and moderate at 45% for the 2014 half-sib progenies and this trait had highly significant and positive correlations with yield. Conclusion: It was concluded that sufficient genetic variability existed among the progenies that could be exploited to improve the population. However, it was recommended that these progenies could also be evaluated in multiple locations to ascertain their adaptability and performance.

scholarly journals Modified Humic Substances as Soil Conditioners: Laboratory and Field Trials

Agronomy ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 150
Author(s):  
Natalia A. Kulikova ◽  
Alexander B. Volikov ◽  
Olga I. Filippova ◽  
Vladimir A. Kholodov ◽  
Nadezhda V. Yaroslavtseva ◽  
...  
Keyword(s):  
Humic Substances ◽  
Soil Aggregates ◽  
Field Tests ◽  
Performance Testing ◽  
Field Trials ◽  
Soil Conditioner ◽  
Model Soil ◽  
Substrate Induced Respiration ◽  
And Performance ◽  
Survival Of Seedlings

The paper is devoted to the development and performance testing of a soil conditioner based on leonardite humic substances (LHS) modified with 3-aminopropyltriethoxysilane (APTES). The modified HS were obtained by adding APTES to LHS solution at different mass ratios of LHS and APTES, followed by the investigation of siloxane structures using 31Si NMR spectroscopy. The Urbic Technosol was used as a model soil. The size and amount of water-stable soil aggregates were estimated using wet sieving and laser diffraction, respectively. Toxicity was evaluated by monitoring microbial substrate-induced respiration (SIR) and seedling bioassay. Laboratory column experiments demonstrated an increase in water-stability of the 3–5 mm soil aggregates after LHS-APTES application. Field tests showed an increase in the average weighted diameter of micro aggregates (from 59 to 73 μm) and water-stable macroaggregates (from 1.6 to 2.9 mm) due to the LHS-APTES amendment. A substantial increase in SIR from 5 to 9 mg CO2 (kg h)−1 was detected. Better survival of seedlings was observed. The obtained beneficial results indicate that APTES-modified HS can be successfully used as a soil conditioner. The formation of extended siloxane networks was suggested as the main mechanism of the observed improvement in the structure of the amended soils.

Detection of genetic diversity in rough fescue (Festuca campestris Rydb) populations of southern Alberta and British Columbia, Canada, using RAPD markers

2008 ◽  
Vol 88 (2) ◽  
pp. 307-312
Author(s):  
Zhao Mengli ◽  
Han Bing ◽  
Walter D Willms
Keyword(s):  
Genetic Diversity ◽  
British Columbia ◽  
Genetic Distance ◽  
Random Amplified Polymorphic Dna ◽  
Geographic Distance ◽  
Genetic Distances ◽  
Gene Frequencies ◽  
Southern Alberta ◽  
Potential Adaptation ◽  
Rough Fescue

Mountain rough fescue (Festuca campestris Rydb.) is a tufted native grass in southern Alberta and British Columbia, Canada, and has attracted interest for use in reclamation. However, its seed is often available from only a few localized sources and may not be adapted for areas removed from the collection site. We conducted a study to determine the genetic variability among rough fescue populations to assess its potential adaptation. Thirty plants were collected from each of six populations and analyzed using Random Amplified Polymorphic DNA (RAPD). One population (Kamloops, BC) was separated by several mountain ranges from the five easterly Alberta populations.The Kamloops population was also separated from the Alberta populations by genetic distance in two clusters. Of the total genetic variation present in the data, 21% was found among populations while the remaining (79%) was found within populations. Nei’s genetic distances among populations were related to their geographical distances. Genetic differences among populations appeared to be caused primarily by differences in gene frequencies rather than rare genes. Also, genetic diversity appeared to increase from west to east suggesting that the more easterly populations had greater adaptation potential. We speculate that the more easterly populations are less likely to share genes since the prevailing winds are from the west. Germplasm from the more easterly populations may be used with suitable precautions within Alberta and possibly around Kamloops. Key words: Genetic distance, geographic distance, reclamation, potential adaptation

scholarly journals DUNE STABILIZATION WITH A SAND/GEL COMPOSITE SYSTEM

1988 ◽  
Vol 1 (21) ◽  
pp. 118
Author(s):  
M.H. Auerbach ◽  
G.W. Borden ◽  
B.L. Edge
Keyword(s):  
Composite System ◽  
Coastal Dunes ◽  
Field Testing ◽  
Field Trials ◽  
Beach Sand ◽  
Front Face ◽  
Initial Development ◽  
Wave Research ◽  
And Performance ◽  
Temporary Stabilization

The effectiveness of a novel sand/gel composite system for the temporary stabilization of coastal dunes was demonstrated in wavetank and field testing. The composite consists of 97% beach sand and water, with a few percent of a biodegradable aqueous polymeric gel made from nontoxic ingredients. The gel binds the sand into a firm but resilient composite that is natural in appearance and resists erosion from waves and tides. The composite is applied by pneumatic gun to the front face of a dune to a few feet below the berm level for toe protection. This paper describes the initial development and performance of the composite system in wavetank tests at the Oregon State University Wave Research Facility and field trials at Anastasia State Park, St. Augustine, Florida; Chuck's Steak House, Melbourne Beach, Florida; and Ocean Dunes Condominiums, Fort Fisher, North Carolina.

Evaluation and genetic analysis of common bean genotypes (Phaseolus vulgaris L.) at Dibatie and Mandura, Northwestern Ethiopia

2021 ◽  
Vol 7 (5) ◽  
pp. 82-90
Author(s):  
Gezahegn Tefera ◽  
Keyword(s):  
Genetic Variability ◽  
Common Bean ◽  
Coefficient Of Variation ◽  
Environmental Variability ◽  
Genetic Constitution ◽  
Genetic Advance ◽  
Breeding Programs ◽  
Days To Flowering ◽  
Lattice Design ◽  
Component Traits

Assessing and understanding the variations existing in crops due to genetic composition and environmental variability is very important in order to exploit the genetic constitution of crop plants. To this aim, variability measures such as phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) are commonly used. Heritability and genetic advance are major concerns for common bean to identify important traits for common bean genetic improvement. The field experiment was conducted at Mandura and Dibatie research substations working with sixteen genotypes of the common bean during 2017/2018 in lattice design with three replications to evaluate the performance of common bean genotypes and estimate the genetic variability. Heritability and genetic advance were estimated in relation to yield and its component traits for future breeding programs. Combined analysis of variance across locations revealed highly significant variations among genotypes for all traits under study. The PCV ranged from 3.36% for days to flowering to 15.91% for a number of pods per plant while the GCV value ranged from 0.75% for days to flowering to 13.74% for the number of pods per plant. Broad sense heritability values ranged from 5.00% for days to flowering to 84.61% for a hundred seed weight. Generally, the result of the study showed that significant genetic variability among tested genotypes and a simple selection for effective improvement of these traits. Keywords: common bean, genetic variability, genetic advance, heritability

Amisom

2019 ◽  
pp. 167-176
Author(s):  
Najum Mushtaq
Keyword(s):  
Federal Government ◽  
International Security ◽  
Conflict Transformation ◽  
Contextual Analysis ◽  
Peace Building ◽  
Analysis Approach ◽  
African Union ◽  
Security Cooperation ◽  
South Central ◽  
And Performance

This chapter presents a brief review of the African Union Mission in Somalia's (AMISOM) origins, growth, and performance from a Somali peace-building and conflict transformation perspective. It also draws lessons for future international security cooperation as spelt out in the May 2017 New Partnership for Somalia. Employing a comparative contextual analysis approach, the chapter takes stock of AMISOM's intervention against some key objectives listed in its mandate and seeks to answer the question of how the conflict landscape in south-central Somalia has changed since the deployment of AMISOM. It asks whether AMISOM's multi-pronged strategy of complementing the dominant military approaches with support to the Federal Government of Somalia in reconciliation, dialogue, and peace-building has been successful. The chapter also examines AMISOM's military and non-military measures to catalyse progress towards the objective for which this mission was set in motion in 2007.

scholarly journals Closing the Phenotyping Gap: High Resolution UAV Time Series for Soybean Growth Analysis Provides Objective Data from Field Trials

2020 ◽  
Vol 12 (10) ◽  
pp. 1644 ◽  
Author(s):  
Irene Borra-Serrano ◽  
Tom De Swaef ◽  
Paul Quataert ◽  
Jonas Aper ◽  
Aamir Saleem ◽  
...  
Keyword(s):  
Growth Curves ◽  
Canopy Cover ◽  
Field Trials ◽  
Biological Research ◽  
Integrative Approach ◽  
Maximum Height ◽  
Soybean Genotypes ◽  
Multi Temporal ◽  
Field Phenotyping ◽  
And Performance

Close remote sensing approaches can be used for high throughput on-field phenotyping in the context of plant breeding and biological research. Data on canopy cover (CC) and canopy height (CH) and their temporal changes throughout the growing season can yield information about crop growth and performance. In the present study, sigmoid models were fitted to multi-temporal CC and CH data obtained using RGB imagery captured with a drone for a broad set of soybean genotypes. The Gompertz and Beta functions were used to fit CC and CH data, respectively. Overall, 90.4% fits for CC and 99.4% fits for CH reached an adjusted R2 > 0.70, demonstrating good performance of the models chosen. Using these growth curves, parameters including maximum absolute growth rate, early vigor, maximum height, and senescence were calculated for a collection of soybean genotypes. This information was also used to estimate seed yield and maturity (R8 stage) (adjusted R2 = 0.51 and 0.82). Combinations of parameter values were tested to identify genotypes with interesting traits. An integrative approach of fitting a curve to a multi-temporal dataset resulted in biologically interpretable parameters that were informative for relevant traits.

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