No fitness cost associated with Asn-2041-Ile mutation in winter wild oat (Avena ludoviciana) seed germination under various environmental conditions

AbstractKnowledge about the fitness cost imposed by herbicide resistance in weeds is instrumental in devising integrated management methods. The present study investigated the germination response of ACCase-resistant (R) and susceptible (S) winter wild oat under different environmental conditions. The DNA of the plants was sequenced after being extracted and purified. The segregated F2 seeds were subjected to various temperatures, water potentials, NaCl concentrations, different pHs, darkness conditions, and burial depths. The results of the sequencing indicated that Ile-2041-Asn mutation is responsible for the evolution of resistance in the studied winter wild oat plants. The seeds were able to germinate over a wide range of temperatures, osmotic potentials, NaCl concentrations, and pHs. Germination percentage of R and S seeds under dark and light conditions was similar and ranged from 86.3 to 88.3%. The highest emergence percentage for both R and S plants was obtained in 0, 1, and 2 cm depths and ranged from 66.6 to 70.3%. In overall, no differences were observed in the germination response between the R and S winter wild oat plants under all studied conditions. No fitness cost at seed level indicates that control of R winter wild oats is more difficult, and it is essential to adopt crop and herbicide rotation to delay the further evolution of resistance.

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Fitness of Herbicide-Resistant Weeds: Current Knowledge and Implications for Management

Plants ◽

10.3390/plants8110469 ◽

2019 ◽

Vol 8 (11) ◽

pp. 469 ◽

Cited By ~ 5

Author(s):

Vila-Aiub

Keyword(s):

Life History ◽

Herbicide Resistance ◽

Management Practices ◽

Current Knowledge ◽

Resistance Management ◽

Fitness Cost ◽

Plant Fitness ◽

Resistance Mutations ◽

Fitness Costs ◽

Wide Range

Herbicide resistance is the ultimate evidence of the extraordinary capacity of weeds to evolve under stressful conditions. Despite the extraordinary plant fitness advantage endowed by herbicide resistance mutations in agroecosystems under herbicide selection, resistance mutations are predicted to exhibit an adaptation cost (i.e., fitness cost), relative to the susceptible wild-type, in herbicide untreated conditions. Fitness costs associated with herbicide resistance mutations are not universal and their expression depends on the particular mutation, genetic background, dominance of the fitness cost, and environmental conditions. The detrimental effects of herbicide resistance mutations on plant fitness may arise as a direct impact on fitness-related traits and/or coevolution with changes in other life history traits that ultimately may lead to fitness costs under particular ecological conditions. This brings the idea that a “lower adaptive value” of herbicide resistance mutations represents an opportunity for the design of resistance management practices that could minimize the evolution of herbicide resistance. It is evident that the challenge for weed management practices aiming to control, minimize, or even reverse the frequency of resistance mutations in the agricultural landscape is to “create” those agroecological conditions that could expose, exploit, and exacerbate those life history and/or fitness traits affecting the evolution of herbicide resistance mutations. Ideally, resistance management should implement a wide range of cultural practices leading to environmentally mediated fitness costs associated with herbicide resistance mutations.

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Variation of seed germination response to temperature in tomato landraces: An adaptation strategy to environmental conditions

Scientia Horticulturae ◽

10.1016/j.scienta.2021.109987 ◽

2021 ◽

Vol 281 ◽

pp. 109987

Author(s):

Naeimeh Sousaraei ◽

Benjamin Torabi ◽

Kambiz Mashaiekhi ◽

Elias Soltani ◽

Seyyed Javad Mousavizadeh

Keyword(s):

Seed Germination ◽

Environmental Conditions ◽

Adaptation Strategy ◽

Germination Response ◽

Response To Temperature

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Analysis of high yielding maize production - a study based on a commercial crop

Australian Journal of Experimental Agriculture ◽

10.1071/ea06103 ◽

2008 ◽

Vol 48 (3) ◽

pp. 296 ◽

Cited By ~ 5

Author(s):

C. J. Birch ◽

G. McLean ◽

A. Sawers

Keyword(s):

Retrospective Analysis ◽

Environmental Conditions ◽

Sowing Date ◽

Plant Population ◽

Higher Plant ◽

Maize Crop ◽

Wide Range ◽

Commercial Crop ◽

Reduced Temperature

This paper reports on the use of APSIM – Maize for retrospective analysis of performance of a high input, high yielding maize crop and analysis of predicted performance of maize grown with high inputs over the long-term (>100 years) for specified scenarios of environmental conditions (temperature and radiation) and agronomic inputs (sowing date, plant population, nitrogen fertiliser and irrigation) at Boort, Victoria, Australia. It uses a high yielding (17 400 kg/ha dry grain, 20 500 kg/ha at 15% water) commercial crop grown in 2004–05 as the basis of the study. Yield for the agronomic and environmental conditions of 2004–05 was predicted accurately, giving confidence that the model could be used for the detailed analyses undertaken. The analysis showed that the yield achieved was close to that possible with the conditions and agronomic inputs of 2004–05. Sowing dates during 21 September to 26 October had little effect on predicted yield, except when combined with reduced temperature. Single year and long-term analyses concluded that a higher plant population (11 plants/m2) is needed to optimise yield, but that slightly lower N and irrigation inputs are appropriate for the plant population used commercially (8.4 plants/m2). Also, compared with changes in agronomic inputs increases in temperature and/or radiation had relatively minor effects, except that reduced temperature reduces predicted yield substantially. This study provides an approach for the use of models for both retrospective analysis of crop performance and assessment of long-term variability of crop yield under a wide range of agronomic and environmental conditions.

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ASSESSING ENVIRONMENTAL IMPACTS DURING NATURAL DISASTER: THE DEVELOPMENT OF A RAPID ENVIRONMENTAL ASSESSMENT METHODOLOGY

Journal of Environmental Assessment Policy and Management ◽

10.1142/s1464333202001157 ◽

2002 ◽

Vol 04 (04) ◽

pp. 475-492 ◽

Cited By ~ 3

Author(s):

CHARLES KELLY

Keyword(s):

Environmental Impact ◽

Impact Assessment ◽

Environmental Impact Assessment ◽

Environmental Conditions ◽

Environmental Damage ◽

Assessment Procedure ◽

Disaster Victims ◽

Wide Range ◽

Negative Impacts ◽

The Impact

The linkages between disaster and environmental damage are recognized as important to predicting, preventing and mitigating the impact of disasters. Environmental Impact Assessment (EIA) procedures are well developed for non-ndisaster situations. However, they are conceptually and operationally inappropriate for use in disaster conditions, particularly in the first 120 days after the disaster has begun. The paper provides a conceptual overview of the requirements for an environmental impact assessment procedure appropriate for disaster conditions. These requirements are captured in guidelines for a Rapid Environmental Impact Assessment (REA) for use in disasters. The REA guides the collection and assessment of a wide range of factors which can indicate: (1) the negative impacts of a disaster on the environment, (2) the impacts of environmental conditions on the magnitude of a disaster and, (3) the positive or negative impacts of relief efforts on environmental conditions. The REA also provides a foundation for recovery program EIAs, thus improving the overall post disaster recovery process. The REA is designed primarily for relief cadres, but is also expected to be usable as an assessment tool with disaster victims. The paper discusses the field testing of the REA under actual disaster conditions.

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Factors affecting red-osier dogwood seed germination

Canadian Journal of Botany ◽

10.1139/b92-125 ◽

1992 ◽

Vol 70 (5) ◽

pp. 1012-1016 ◽

Cited By ~ 4

Author(s):

S. N. Acharya ◽

C. B. Chu ◽

R. Hermesh ◽

G. B. Schaalje

Keyword(s):

Seed Germination ◽

Germination Percentage ◽

Collection Site ◽

Moisture Condition ◽

Seed Formation ◽

Factors Affecting ◽

Year Effect ◽

Wide Range ◽

Cornus Stolonifera ◽

Moisture Conditions

Seeds from 55 populations of native Alberta red-osier dogwood (Cornus stolonifera Michx.) were collected over 2 years (1984 and 1985) to determine the range of variability for seed germination and the effect of ecoregion and moisture conditions in the collection sites on this trait. Each year the unscarified seeds were stored at 3 °C for 30 days, stratified at 3 °C for an additional 30 days and then incubated on an 8 h light: 16 h dark cycle at a temperature of 25:10 °C (light:dark) for germination. A wide range of germination percentages was observed among populations collected in any 1 year. However, the variability was not due to the ecoregion or moisture condition of the collection site. Germination percentage of populations collected in 1984 and 1985 formed five and seven groups, respectively. A study involving eight sites that were common to 1984, 1985, and 1986 revealed a significant effect of population on seed germination. This population effect was not obscured by the combined effects of year, precipitation, temperature, and seed size. The year effect was significant only when population was used as a covariate. Precipitation during seed formation significantly influenced germination performance even after adjustments were made for population and year. Seed germination in red-osier dogwood appears to be influenced by the population from which the seeds are collected and by yearly environmental fluctuations. Therefore, germination studies in this species must include seeds from diverse populations collected over several years. Key words: red-osier dogwood, Cornus stolonifera Michx., germination, population, environment.

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Ozone damage, detoxification and the role of isoprenoids – new impetus for integrated models

Functional Plant Biology ◽

10.1071/fp15302 ◽

2016 ◽

Vol 43 (4) ◽

pp. 324 ◽

Cited By ~ 15

Author(s):

Supriya Tiwari ◽

Rüdiger Grote ◽

Galina Churkina ◽

Tim Butler

Keyword(s):

Stomatal Conductance ◽

Environmental Conditions ◽

Economic Losses ◽

Plant Responses ◽

Damage Scenarios ◽

Biochemical Processes ◽

Wide Range ◽

Defence Responses ◽

High Concentrations ◽

The Impact

High concentrations of ozone (O3) can have significant impacts on the health and productivity of agricultural and forest ecosystems, leading to significant economic losses. In order to estimate this impact under a wide range of environmental conditions, the mechanisms of O3 impacts on physiological and biochemical processes have been intensively investigated. This includes the impact on stomatal conductance, the formation of reactive oxygen species and their effects on enzymes and membranes, as well as several induced and constitutive defence responses. This review summarises these processes, discusses their importance for O3 damage scenarios and assesses to which degree this knowledge is currently used in ecosystem models which are applied for impact analyses. We found that even in highly sophisticated models, feedbacks affecting regulation, detoxification capacity and vulnerability are generally not considered. This implies that O3 inflicted alterations in carbon and water balances cannot be sufficiently well described to cover immediate plant responses under changing environmental conditions. Therefore, we suggest conceptual models that link the depicted feedbacks to available process-based descriptions of stomatal conductance, photosynthesis and isoprenoid formation, particularly the linkage to isoprenoid models opens up new options for describing biosphere-atmosphere interactions.

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Distribution, feeding behaviour, and condition of Cape horse mackerel early life stages, Trachurus capensis, under different environmental conditions in the northern Benguela upwelling ecosystem

ICES Journal of Marine Science ◽

10.1093/icesjms/fsu087 ◽

2014 ◽

Vol 72 (2) ◽

pp. 543-557 ◽

Cited By ~ 3

Author(s):

S. J. Geist ◽

A. Kunzmann ◽

H. M. Verheye ◽

A. Eggert ◽

A. Schukat ◽

...

Keyword(s):

Dissolved Oxygen ◽

Feeding Ecology ◽

Environmental Conditions ◽

Early Life ◽

Early Life History ◽

Horse Mackerel ◽

Larval Phase ◽

Recruitment Success ◽

Wide Range ◽

Variable Recruitment

Abstract Early life history (ELH) traits are key to understand variable recruitment success and hence the stock size of marine fish. One of the currently most puzzling ecosystems in this regard is the northern part of the Benguela Current upwelling system off Namibia. Here, populations of the formerly dominant pelagic species, sardine and anchovy, failed to recover during the last three decades after a dramatic decline. In contrast, Cape horse mackerel, Trachurus capensis, maintained a constant population size. Warming of the system and shoaling of hypoxic zones together with feedback loops within an altered foodweb are discussed to be responsible for this regime shift. In this study, we address the role of larval traits for the successful performance of the T. capensis population under the present environmental conditions with the focus on feeding ecology. We investigated seasonal variations of the geographical distribution, growth rate, feeding ecology, and nutritional condition of their ELH stages and examined relationships with water temperature, dissolved oxygen concentration, and micro-zooplankton composition. T. capensis' ELH stages showed a wide spatial and seasonal distribution, a preference for higher water temperatures (18–21°C) and presence over a wide range of dissolved oxygen concentrations (0.13–6.35 ml O2 l−1). Feeding success was high and mainly different groups of Copepoda were targeted, which were strongly size selected. The high dietary importance of micro-copepods during large parts of the larval phase indicates successful exploitation of this food source, which has increased in abundance during the last decade. It also explains observed best nutritional conditions at temperatures between 18 and 21°C, since these small copepods are commonly associated with warmer temperatures. Altogether, these traits enhance the species' probability to encounter suitable environments for the survival of their ELH stages, which is likely to lead to their high recruitment success in the northern Benguela ecosystem.

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Seed germination response of a noxious agricultural weed Echium plantagineum to temperature, light, pH, drought stress, salinity, heat and smoke

Crop and Pasture Science ◽

10.1071/cp17308 ◽

2018 ◽

Vol 69 (3) ◽

pp. 326 ◽

Cited By ~ 4

Author(s):

Singarayer Florentine ◽

Sandra Weller ◽

Alannah King ◽

Arunthathy Florentine ◽

Kim Dowling ◽

...

Keyword(s):

Soil Moisture ◽

Drought Stress ◽

Invasive Weed ◽

Germination Response ◽

Elevated Salinity ◽

Wide Range ◽

Agricultural Weed ◽

Soil Seedbank ◽

Response To Temperature ◽

Salinity Management

Echium plantagineum is a significant pasture weed in the Mediterranean climatic zone of several countries, including Australia. This invasive weed, introduced as an ornamental into Australia (where it is known as Paterson’s curse), quickly became established and is now a significant weed of agriculture. Although E. plantagineum is a well-established, highly competitive weed that thrives under disturbance and is tolerant of a wide variety of conditions, including varying soil moisture and drought, and some aspects of its ecology remain unknown. This study investigated germination response to temperature and light, pH, soil moisture, salinity, and pre-germination exposure of seed to heat and smoke. Temperature was found to be more influential on germination than light and the species is tolerant to a wide range of pH. However, available moisture may limit germination, as may elevated salinity. Management of this weed requires approaches that minimise soil seedbank input or prevent germination of soil seedbanks.

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Urochloa platyphylla (broadleaf signalgrass).

10.1079/cpc.9669.20210099877 ◽

2021 ◽

Author(s):

Julissa Rojas-Sandoval ◽

Pedro Acevedo-Rodríguez

Keyword(s):

Environmental Conditions ◽

Crop Residue ◽

Soil Surface ◽

Grass Species ◽

Crop Fields ◽

Wide Range ◽

Germinating Seeds

Abstract U. platyphylla is a weedy grass species commonly found in disturbed, open and sandy sites such as crop fields, ditches and roadsides. It is considered a troublesome weed because of its tolerance to some herbicides principally in maize plantations (Chamblee et al., 1982; Gallaher et al.,1999). U. platyphylla is highly adaptable and it is able to germinate and grow throughout a wide range of soil and environmental conditions (Burke et al., 2003). Additionally, its seeds may remain on the crop residue until pre-emergence herbicides are no longer effective in controlling the germinating seeds, at which time the seeds fall to the soil surface and germinate (Alford et al., 2005).

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Germination Ecology of Catchfly (Silene conoidea) Seeds of Different Colors

Planta Daninha ◽

10.1590/s0100-83582017350100030 ◽

2017 ◽

Vol 35 (0) ◽

Cited By ~ 2

Author(s):

A. TANVEER ◽

M.M. JAVAID ◽

R.N. ABBAS ◽

H.H. ALI ◽

M.Q. NAZIR ◽

...

Keyword(s):

Osmotic Stress ◽

Environmental Conditions ◽

Climatic Conditions ◽

Burial Depth ◽

Weed Species ◽

Successful Management ◽

Nacl Concentration ◽

Seed Polymorphism ◽

Emergence Percentage ◽

Annual Herb

ABSTRACT Catchfly (Silene conoidea), an annual herb, is usually recognized as an emerging weed species in Eurasia and North America. The presence of somatic seed polymorphism might aid in the adaptation of this weed in different climatic conditions. We conducted laboratory and greenhouse experiments to study the seed polymorphism and influence of various environmental factors like temperature, salt stress, osmotic stress and burial depth on the germination and emergence characteristics of catchfly. Optimum germination of seeds of all colors was recorded at a temperature of 15 oC. Germination of catchfly seeds of all colors followed decreasing trend as NaCl concentration increased from 50 mM to 200 mM. Seed germination was maximum (87-96%) at 0 MPa but gradually decreased to 40% as osmotic stress increases up to -0.4 MPa and completely inhibited at 0.6 MPa of all seed colors. A slight increase (from 60 to 95%) in the germination of seeds of black and dark brown colors was observed when seeding depth increased from 0 to 2 cm but decreased when seeding depth increased from 2 to 4 cm in seeds of all colors. There was no emergence of catchfly at seeding depth of 6 cm or greater. Our results concluded that catchfly seeds have the potential to germinate and emerge in various environmental conditions, but germination/emergence percentage of seeds of all colors will be different in different environmental conditions. Soil amendments including deep ploughing may aid for the successful management of this weed in cultivated areas.

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