WorldWideScience

Sample records for california perennial crop

  1. Impacts of Future Climate Change on California Perennial Crop Yields: Model Projections with Climate and Crop Uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Lobell, D; Field, C; Cahill, K; Bonfils, C

    2006-01-10

    Most research on the agricultural impacts of climate change has focused on the major annual crops, yet perennial cropping systems are less adaptable and thus potentially more susceptible to damage. Improved assessments of yield responses to future climate are needed to prioritize adaptation strategies in the many regions where perennial crops are economically and culturally important. These impact assessments, in turn, must rely on climate and crop models that contain often poorly defined uncertainties. We evaluated the impact of climate change on six major perennial crops in California: wine grapes, almonds, table grapes, oranges, walnuts, and avocados. Outputs from multiple climate models were used to evaluate climate uncertainty, while multiple statistical crop models, derived by resampling historical databases, were used to address crop response uncertainties. We find that, despite these uncertainties, climate change in California is very likely to put downward pressure on yields of almonds, walnuts, avocados, and table grapes by 2050. Without CO{sub 2} fertilization or adaptation measures, projected losses range from 0 to >40% depending on the crop and the trajectory of climate change. Climate change uncertainty generally had a larger impact on projections than crop model uncertainty, although the latter was substantial for several crops. Opportunities for expansion into cooler regions are identified, but this adaptation would require substantial investments and may be limited by non-climatic constraints. Given the long time scales for growth and production of orchards and vineyards ({approx}30 years), climate change should be an important factor in selecting perennial varieties and deciding whether and where perennials should be planted.

  2. Perennial Grain and Oilseed Crops.

    Science.gov (United States)

    Kantar, Michael B; Tyl, Catrin E; Dorn, Kevin M; Zhang, Xiaofei; Jungers, Jacob M; Kaser, Joe M; Schendel, Rachel R; Eckberg, James O; Runck, Bryan C; Bunzel, Mirko; Jordan, Nick R; Stupar, Robert M; Marks, M David; Anderson, James A; Johnson, Gregg A; Sheaffer, Craig C; Schoenfuss, Tonya C; Ismail, Baraem; Heimpel, George E; Wyse, Donald L

    2016-04-29

    Historically, agroecosystems have been designed to produce food. Modern societies now demand more from food systems-not only food, fuel, and fiber, but also a variety of ecosystem services. And although today's farming practices are producing unprecedented yields, they are also contributing to ecosystem problems such as soil erosion, greenhouse gas emissions, and water pollution. This review highlights the potential benefits of perennial grains and oilseeds and discusses recent progress in their development. Because of perennials' extended growing season and deep root systems, they may require less fertilizer, help prevent runoff, and be more drought tolerant than annuals. Their production is expected to reduce tillage, which could positively affect biodiversity. End-use possibilities involve food, feed, fuel, and nonfood bioproducts. Fostering multidisciplinary collaborations will be essential for the successful integration of perennials into commercial cropping and food-processing systems. PMID:26789233

  3. Agroecology of Novel Annual and Perennial Crops for Biomass Production

    DEFF Research Database (Denmark)

    Manevski, Kiril; Jørgensen, Uffe; Lærke, Poul Erik

    The agroecological potential of many crops under sustainable intensification has not been investigated. This study investigates such potential for novel annual and perennial crops grown for biomass production.......The agroecological potential of many crops under sustainable intensification has not been investigated. This study investigates such potential for novel annual and perennial crops grown for biomass production....

  4. Ratooning and perennial staple crops in Malawi. A review

    NARCIS (Netherlands)

    Rogé, Paul; Snapp, Sieglinde; Kakwera, Mayamiko Nathaniel; Mungai, Leah; Jambo, Isaac; Peter, Brad

    2016-01-01

    The management of staple crops as perennials is a historic legacy and a present-day strategy in some regions of Sub-Saharan Africa, yet perenniality is rarely an agronomic subject. Farmers in Malawi cut annual crops, such as pigeonpea and sorghum, to extend production for more than one growing se

  5. Closing the Carbon Budget in Perennial Biofuel Crops

    Science.gov (United States)

    Kantola, I. B.; Anderson-Teixeira, K. J.; Bernacchi, C.; Hudiburg, T. W.; Masters, M. D.; DeLucia, E. H.

    2013-12-01

    At present, some 40% of corn grown in the United States, accounting for more than 26 million acres of farmland, is processed for bioethanol. Interest has arisen in converting biofuel production from corn grain ethanol to cellulosic ethanol, derived primarily from cellulose from dedicated energy crops. As many cellulosic biofuel feedstocks are perennial grasses, conversion from annual corn cropping to perennials represents a substantial change in farming practices with the potential to alter the plant-soil relationship in the Midwestern United States. Elimination of annual tillage preserves soils structure, conserving soil carbon and maintaining plant root systems. Five years of perennial grass establishment in former agricultural land in Illinois has shown a significant change in soil carbon pools and fluxes. Atmospheric carbon exchange monitoring combined with vegetation and soil sampling and respiration measurements confirm that in the first 3 years (establishment phase), perennial giant grasses Miscanthus x giganteus and Panicum virgatum rapidly increased belowground carbon allocation >400% and belowground biomass 400-750% compared to corn. Following establishment, perennial grasses maintained below- and aboveground annual biomass production, out-performing corn in both average and drought conditions. Here we offer a quantitative comparison of the carbon allocation pathways of corn and perennial biofuel crops in Midwestern landscapes, demonstrating the carbon benefits of perennial cropping through increased C allocation to root and rhizome structures. Long rotation periods in perennial grasses combined with annual carbon inputs to the soil system are expected to convert these agricultural soils from atmospheric carbon sources to carbon sinks.

  6. Impact of perennial energy crops income variability on the crop selection of risk averse farmers

    International Nuclear Information System (INIS)

    The UK Government policy is for the area of perennial energy crops in the UK to expand significantly. Farmers need to choose these crops in preference to conventional rotations for this to be achievable. This paper looks at the potential level and variability of perennial energy crop incomes and the relation to incomes from conventional arable crops. Assuming energy crop prices are correlated to oil prices the results suggests that incomes from them are not well correlated to conventional arable crop incomes. A farm scale mathematical programming model is then used to attempt to understand the affect on risk averse farmers crop selection. The inclusion of risk reduces the energy crop price required for the selection of these crops. However yields towards the highest of those predicted in the UK are still required to make them an optimal choice, suggesting only a small area of energy crops within the UK would be expected to be chosen to be grown. This must be regarded as a tentative conclusion, primarily due to high sensitivity found to crop yields, resulting in the proposal for further work to apply the model using spatially disaggregated data. - Highlights: ► Energy crop and conventional crop incomes suggested as uncorrelated. ► Diversification effect of energy crops investigated for a risk averse farmer. ► Energy crops indicated as optimal selection only on highest yielding UK sites. ► Large establishment grant rates to substantially alter crop selections.

  7. Modelling farmer uptake of perennial energy crops in the UK

    Energy Technology Data Exchange (ETDEWEB)

    Sherrington, Chris; Moran, Dominic [Scottish Agricultural College, West Mains Road, Edinburgh EH9 3JG (United Kingdom)

    2010-07-15

    The UK Biomass Strategy suggests that to reach the technical potential of perennial energy crops such as short rotation coppice (SRC) willow and miscanthus by 2020 requires 350,000 hectares of land. This represents a more than 20-fold increase on the current 15,546 hectares. Previous research has identified several barriers to adoption, including concerns over security of income from contracts. In addition, farmers perceive returns from these crops to be lower than for conventional crops. This paper uses a farm-level linear programming model to investigate theoretical uptake of energy crops at different gross margins under the assumption of a profit-maximising decision maker, and in the absence of known barriers to adoption. The findings suggest that while SRC willow, at current prices, remains less competitive, returns to miscanthus should have encouraged adoption on a wider scale than at present. This highlights the importance of the barriers to adoption. Recently announced contracts for miscanthus appear to offer a significant premium to farmers in order to encourage them to grow the crops. This raises the question of whether a more cost-effective approach would be for government to provide guarantees addressing farmers concerns including security of income from the contracts. Such an approach should encourage adoption at lower gross margins. (author)

  8. Gene flow in genetically engineered perennial grasses: Lessons for modification of dedicated bioenergy crops

    Science.gov (United States)

    The potential ecological consequences of the commercialization of genetically engineered (GD) crops have been the subject of intense debate, particularly when the GE crops are perennial and capable of outcrossing to wild relatives. The essential ecological impact issues for engi...

  9. Perennial kales: collection rationalization and genetic relatedness to other Brassica oleracea crop

    NARCIS (Netherlands)

    Treuren, van R.; Bas, N.

    2008-01-01

    Perennial kale is a rare leafy vegetable and forage crop that is mainly vegetatively propagated and therefore expensive to conserve ex situ. A genebank collection of 47 perennial kales and 34 reference samples from the main Brassica oleracea crop types were characterized with seven microsatellite ma

  10. Reduced nitrogen losses after conversion of row crop agriculture to perennial biofuel crops.

    Science.gov (United States)

    Smith, Candice M; David, Mark B; Mitchell, Corey A; Masters, Michael D; Anderson-Teixeira, Kristina J; Bernacchi, Carl J; Delucia, Evan H

    2013-01-01

    Current biofuel feedstock crops such as corn lead to large environmental losses of N through nitrate leaching and NO emissions; second-generation cellulosic crops have the potential to reduce these N losses. We measured N losses and cycling in establishing miscanthus (), switchgrass ( L. fertilized with 56 kg N ha yr), and mixed prairie, along with a corn ( L.)-corn-soybean [ (L.) Merr.] rotation (corn fertilized at 168-202 kg N ha). Nitrous oxide emissions, soil N mineralization, mid-profile nitrate leaching, and tile flow and nitrate concentrations were measured. Perennial crops quickly reduced nitrate leaching at a 50-cm soil depth as well as concentrations and loads from the tile systems (year 1 tile nitrate concentrations of 10-15 mg N L declined significantly by year 4 in all perennial crops to <0.6 mg N L, with losses of <0.8 kg N ha yr). Nitrous oxide emissions were 2.2 to 7.7 kg N ha yr in the corn-corn-soybean rotation but were <1.0 kg N ha yr by year 4 in the perennial crops. Overall N balances (atmospheric deposition + fertilization + soybean N fixation - harvest, leaching losses, and NO emissions) were positive for corn and soybean (22 kg N ha yr) as well as switchgrass (9.7 kg N ha yr) but were -18 and -29 kg N ha yr for prairie and miscanthus, respectively. Our results demonstrate rapid tightening of the N cycle as perennial biofuel crops established on a rich Mollisol soil. PMID:23673757

  11. Can exotic phytoseiids be considered 'benevolent invaders' in perennial cropping systems?

    Science.gov (United States)

    Palevsky, Eric; Gerson, Uri; Zhang, Zhi-Qiang

    2013-02-01

    Numerous natural enemies were adopted worldwide for the control of major pests, including exotic phytoseiid species (Acari: Mesostigmata: Phytoseiidae) that had been moved from continent to continent in protected and perennial agricultural systems. However, relatively fewer successes were recorded in perennial agricultural systems. In this manuscript we focus on the question: Can and will exotic phytoseiids provide better pest control than indigenous species in perennial agricultural systems? To answer this question, we review the efficacy of biological control efforts with phytoseiids in several case studies, where exotic and indigenous species were used against pests on indigenous host plants and some crops that were historically or recently introduced. Related factors affecting predator establishment, such as intraguild predation and pesticide effects are discussed, as well as the potential negative effects of exotic species releases on biological control and their impact on the indigenous natural fauna. On citrus, apple, grape and cassava exotic phytoseiids have enhanced biological control without negatively affecting indigenous species of natural enemies, except for the case of Euseius stipulatus (Athias-Henriot) on citrus that displaced Euseius hibisci (Chant) in a limited region of coastal California, USA, the latter considered to be an inferior biocontrol agent of Panonychus citri Koch. Phytoseiulus persimilis Athias-Henriot on gorse, an invasive weed, is perhaps the only recorded case of a negative effect of an established exotic phytoseiid on biological control. PMID:22669275

  12. Methyl halide and biogenic volatile organic compound fluxes from perennial bioenergy crops and annual arable crops

    OpenAIRE

    Morrison, Eilidh Christina

    2013-01-01

    The depletion of fossil fuel resources, pollution concerns and the challenge of energy security are driving the search for renewable energy sources. The use of lignocellulosic plant biomass as an energy source is increasing in the United Kingdom and worldwide. In the UK, up to 0.35MHa (6% of total arable land) may be planted with perennial bioenergy crops by 2020 in order to meet renewable energy and CO2 reduction targets. Several plant species that produce high biomass from lo...

  13. Energy balance and cost-benefit analysis of biogas production from perennial energy crops pretreated by wet oxidation

    DEFF Research Database (Denmark)

    Uellendahl, Hinrich; Wang, Guangtao; Møller, Henrik B.;

    2008-01-01

    Perennial crops need far less energy to plant, require less fertilizer and pesticides, and show a lower negative environmental impact compared with annual crops like for example corn. This makes the cultivation of perennial crops as energy crops more sustainable than the use of annual crops....... The conversion into biogas in anaerobic digestion plants shows however much lower specific methane yields for the raw perennial crops like miscanthus and willow due to their lignocellulosic structure. Without pretreatment the net energy gain is therefore lower for the perennials than for corn. When applying wet...... oxidation to the perennial crops, however, the specific methane yield increases significantly and the ratio of energy output to input and of costs to benefit for the whole chain of biomass supply and conversion into biogas becomes higher than for corn. This will make the use of perennial crops as energy...

  14. A Systematic Review of Perennial Staple Crops Literature Using Topic Modeling and Bibliometric Analysis.

    Science.gov (United States)

    Kane, Daniel A; Rogé, Paul; Snapp, Sieglinde S

    2016-01-01

    Research on perennial staple crops has increased in the past ten years due to their potential to improve ecosystem services in agricultural systems. However, multiple past breeding efforts as well as research on traditional ratoon systems mean there is already a broad body of literature on perennial crops. In this review, we compare the development of research on perennial staple crops, including wheat, rice, rye, sorghum, and pigeon pea. We utilized the advanced search capabilities of Web of Science, Scopus, ScienceDirect, and Agricola to gather a library of 914 articles published from 1930 to the present. We analyzed the metadata in the entire library and in collections of literature on each crop to understand trends in research and publishing. In addition, we applied topic modeling to the article abstracts, a type of text analysis that identifies frequently co-occurring terms and latent topics. We found: 1.) Research on perennials is increasing overall, but individual crops have each seen periods of heightened interest and research activity; 2.) Specialist journals play an important role in supporting early research efforts. Research often begins within communities of specialists or breeders for the individual crop before transitioning to a more general scientific audience; 3.) Existing perennial agricultural systems and their domesticated crop material, such as ratoon rice systems, can provide a useful foundation for breeding efforts, accelerating the development of truly perennial crops and farming systems; 4.) Primary research is lacking for crops that are produced on a smaller scale globally, such as pigeon pea and sorghum, and on the ecosystem service benefits of perennial agricultural systems.

  15. A Systematic Review of Perennial Staple Crops Literature Using Topic Modeling and Bibliometric Analysis

    Science.gov (United States)

    2016-01-01

    Research on perennial staple crops has increased in the past ten years due to their potential to improve ecosystem services in agricultural systems. However, multiple past breeding efforts as well as research on traditional ratoon systems mean there is already a broad body of literature on perennial crops. In this review, we compare the development of research on perennial staple crops, including wheat, rice, rye, sorghum, and pigeon pea. We utilized the advanced search capabilities of Web of Science, Scopus, ScienceDirect, and Agricola to gather a library of 914 articles published from 1930 to the present. We analyzed the metadata in the entire library and in collections of literature on each crop to understand trends in research and publishing. In addition, we applied topic modeling to the article abstracts, a type of text analysis that identifies frequently co-occurring terms and latent topics. We found: 1.) Research on perennials is increasing overall, but individual crops have each seen periods of heightened interest and research activity; 2.) Specialist journals play an important role in supporting early research efforts. Research often begins within communities of specialists or breeders for the individual crop before transitioning to a more general scientific audience; 3.) Existing perennial agricultural systems and their domesticated crop material, such as ratoon rice systems, can provide a useful foundation for breeding efforts, accelerating the development of truly perennial crops and farming systems; 4.) Primary research is lacking for crops that are produced on a smaller scale globally, such as pigeon pea and sorghum, and on the ecosystem service benefits of perennial agricultural systems. PMID:27213283

  16. Direct control of perennial weeds between crops - Implication for organic farming

    DEFF Research Database (Denmark)

    Melander, Bo; Holst, Niels; Rasmussen, Ilse Ankjær;

    2012-01-01

    and mouldboard ploughing appear to be effective solutions against mixed stands of perennials on sandy soils but they do not comply with optimal nutrient management in organic cropping. Therefore, intensive autumn cultivation is only relevant where a perennial weed problem is uncontrollable by other means.......Perennial weeds can be a major constraint to organic crop production and direct control actions applied between crops can then be necessary to reduce the problems. We conducted two experiments, one on a sandy loam and one on a sandy soil in Denmark, with the aim of studying the efficacy......, power take-off driven implements with rotating weeding devices demonstrated similar control efficacies against a mixed stand composing C. arvense, Tussilago farfara, Elytrigia repens and Artemisia vulgaris. One pass was conducted a week after barley harvest followed by another pass 3 weeks later...

  17. Candidate perennial bioenergy grasses have a higher albedo than annual row crops

    Science.gov (United States)

    Miller, J. N.; VanLoocke, A.; Gomez-Casanovas, N.; Bernacchi, C.

    2015-12-01

    The production of perennial cellulosic feedstocks for bioenergy presents the potential to diversify regional economies and the national energy supply, while also serving as climate 'regulators' due to a number of biogeochemical and biogeophysical differences relative to row crops. Numerous observational and model based approaches have investigated biogeochemical tradeoffs, such as increased carbon sequestration and increased water use, associated with growing cellulosic feedstocks. A less understood aspect is the biogeophysical changes associated with the difference in albedo (α), which could alter the local energy balance and cause local to regional cooling several times larger than that associated with offsetting carbon. Here, we established paired fields of Miscanthus × giganteus (miscanthus) and Panicum virgatum (switchgrass), two of the leading perennial cellulosic feedstock candidates, and traditional annual row crops in the highly productive "Corn-belt". Our results show that miscanthus did and switchgrass did not have an overall higher α than current row crops but a strong seasonal pattern existed. Both perennials had consistently higher growing season α than row crops and winter α did not differ. The lack of observed differences in winter α, however, masked an interaction between snow cover and species differences, with the perennial species, compared with the row crops, having a higher α when snow was absent and a much lower α when snow was present. Overall, these changes resulted in an average net reduction in annual absorbed energy of about 5 W/m2 for switchgrass and about 8 W/m2 for miscanthus relative to annual crops. Therefore, the conversion from annual row to perennial crops alters the radiative balance of the surface via changes in α and could lead to regional cooling.

  18. Medium-term effect of perennial energy crops on soil organic carbon storage

    Directory of Open Access Journals (Sweden)

    Enrico Ceotto

    2011-11-01

    Full Text Available The scope of this study was to evaluate the effect of perennial energy crops on soil organic carbon (SOC storage. A field experiment was undertaken in 2002 at Anzola dell’Emilia in the lower Po Valley, Northern Italy. Five perennial energy crops were established on a land area which had been previously cultivated with arable crops for at least 20 years. The compared crops are: the herbaceous perennials giant reed and miscanthus, and the woody species poplar, willow and black locust, managed as short rotation coppice (SRC. SOC was measured in 2009, seven years after the start of the experiment, on an upper soil layer of 0.0-0.2 m and a lower soil layer of 0.2-0.4 m. The study aimed to compare the SOC storage of energy crops with alternative land use. Therefore, two adjacent areas were sampled in the same soil layers: i arable land in steady state, cultivated with rainfed annual crops; ii natural meadow established at the start of the experiment. The conversion of arable land into perennial energy crops resulted in SOC storage, in the upper soil layer (0.0-0.2 m ranging from 1150 to 1950 kg C ha-1 year-1 during the 7-year period. No significant differences were detected in SOC among crop species. We found no relationship between the harvested dry matter and the SOC storage. The conversion of arable land into perennial energy crops provides a substantial SOC sequestration benefit even when the hidden C cost of N industrial fertilizers is taken into account. While the SOC increased, the total N content in the soil remained fairly constant. This is probably due to the low rate of nitrogen applied to the perennial crops. However, our data are preliminary and the number of years in which the SOC continues to increase needs to be quantified, especially for the herbaceous species giant reed and miscanthus, with a supposedly long duration of the useful cropping cycle of 20 years or longer.

  19. Energy balance and cost-benefit analysis of biogas production from perennial energy crops pretreated by wet oxidation

    DEFF Research Database (Denmark)

    Uellendahl, Hinrich; Wang, Guangtao; Møller, H.B.;

    2008-01-01

    oxidation to the perennial crops, however, the specific methane yield increases significantly and the ratio of energy output to input and of costs to benefit for the whole chain of biomass supply and conversion into biogas becomes higher than for corn. This will make the use of perennial crops as energy...

  20. Energy balance and cost-benefit analysis of biogas production from perennial energy crops pretreated by wet oxidation.

    Science.gov (United States)

    Uellendahl, H; Wang, G; Møller, H B; Jørgensen, U; Skiadas, I V; Gavala, H N; Ahring, B K

    2008-01-01

    Perennial crops need far less energy to plant, require less fertilizer and pesticides, and show a lower negative environmental impact compared with annual crops like for example corn. This makes the cultivation of perennial crops as energy crops more sustainable than the use of annual crops. The conversion into biogas in anaerobic digestion plants shows however much lower specific methane yields for the raw perennial crops like miscanthus and willow due to their lignocellulosic structure. Without pretreatment the net energy gain is therefore lower for the perennials than for corn. When applying wet oxidation to the perennial crops, however, the specific methane yield increases significantly and the ratio of energy output to input and of costs to benefit for the whole chain of biomass supply and conversion into biogas becomes higher than for corn. This will make the use of perennial crops as energy crops competitive to the use of corn and this combination will make the production of biogas from energy crops more sustainable. PMID:19029727

  1. Role of organic matter on trace metal availability in contaminated soils: case of high biomass perennial crops vs annual crops

    Science.gov (United States)

    Lamy, I.; Beaumelle, L.; Iqbal, M.; Chenu, C.

    2012-04-01

    Soils of contaminated agrosystems are still potential arable surfaces for the production of non-alimentary crops provided that such cropping systems do not increase risks for the environment in order to integrate them in a sustainable agriculture development. Effects of changing land management from annual to perennial on soil properties have been widely studied over the last decades, but the case of contaminated agricultural soils remains little documented in particular concerning the effects on the dynamic of soil trace elements. Among the non-alimentary crops, the use of energy crops like miscanthus, a C4 perennial plant, must be studied in particular to evaluate their environmental impacts as they are known to modify the soil organic matter pools. In this work we aimed at assessing changes in soil trace metal availability when annual crops are replaced by a perennial cropping system in a metal contaminated soil, with the hypothesis that exogenous organic carbon originating from the plant induced changes in the soil metal speciation. For this, we used the soil surface horizons of a smelter impacted parcel in the North of France, whose one part was cultivated in miscanthus three years ago and the other part was left with the previous land use i.e. cropping rotations. We quantified the carbon fluxes originating from miscanthus in the various granulo-densimetric fractions of the soil under miscanthus by C13 measurements, and compared the chemical extraction and the physical localisation of both organic carbon and of two trace metal, Cu and Zn in the various soil size fractions of both soils under miscanthus and under annual crops. Results showed an incorporation of organic carbon from miscanthus in the coarse organic fractions which was related to an increase in the metal localisation in the coarse grain fractions observed for Cu but not for Zn. Comparison of metal availabilities between the two cropping systems showed no difference for Zn availability while copper

  2. Comparative water use by maize, perennial crops, restored prairie, and poplar trees in the US Midwest

    Science.gov (United States)

    Hamilton, S. K.; Hussain, M. Z.; Bhardwaj, A. K.; Basso, B.; Robertson, G. P.

    2015-06-01

    Water use by plant communities across years of varying water availability indicates how terrestrial water balances will respond to climate change and variability as well as to land cover change. Perennial biofuel crops, likely grown mainly on marginal lands of limited water availability, provide an example of a potentially extensive future land cover conversion. We measured growing-season evapotranspiration (ET) based on daily changes in soil profile water contents in five perennial systems—switchgrass, miscanthus, native grasses, restored prairie, and hybrid poplar—and in annual maize (corn) in a temperate humid climate (Michigan, USA). Three study years (2010, 2011 and 2013) had normal growing-season rainfall (480-610 mm) whereas 2012 was a drought year (210 mm). Over all four years, mean (±SEM) growing-season ET for perennial systems did not greatly differ from corn (496 ± 21 mm), averaging 559 (±14), 458 (±31), 573 (±37), 519 (±30), and 492 (±58) mm for switchgrass, miscanthus, native grasses, prairie, and poplar, respectively. Differences in biomass production largely determined variation in water use efficiency (WUE). Miscanthus had the highest WUE in both normal and drought years (52-67 and 43 kg dry biomass ha-1 mm-1, respectively), followed by maize (40-59 and 29 kg ha-1 mm-1) the native grasses and prairie were lower and poplar was intermediate. That measured water use by perennial systems was similar to maize across normal and drought years contrasts with earlier modeling studies and suggests that rain-fed perennial biomass crops in this climate have little impact on landscape water balances, whether replacing rain-fed maize on arable lands or successional vegetation on marginal lands. Results also suggest that crop ET rates, and thus groundwater recharge, streamflow, and lake levels, may be less sensitive to climate change than has been assumed.

  3. Direct climate effects of perennial bioenergy crops in the United States

    OpenAIRE

    Georgescu, Matei; Lobell, David B.; Field, Christopher B

    2011-01-01

    Biomass-derived energy offers the potential to increase energy security while mitigating anthropogenic climate change, but a successful path toward increased production requires a thorough accounting of costs and benefits. Until recently, the efficacy of biomass-derived energy has focused primarily on biogeochemical consequences. Here we show that the biogeophysical effects that result from hypothetical conversion of annual to perennial bioenergy crops across the central United States impart ...

  4. Modelling the perennial energy crop market: the role of spatial diffusion.

    Science.gov (United States)

    Alexander, Peter; Moran, Dominic; Rounsevell, Mark D A; Smith, Pete

    2013-11-01

    Biomass produced from energy crops, such as Miscanthus and short rotation coppice is expected to contribute to renewable energy targets, but the slower than anticipated development of the UK market implies the need for greater understanding of the factors that govern adoption. Here, we apply an agent-based model of the UK perennial energy crop market, including the contingent interaction of supply and demand, to understand the spatial and temporal dynamics of energy crop adoption. Results indicate that perennial energy crop supply will be between six and nine times lower than previously published, because of time lags in adoption arising from a spatial diffusion process. The model simulates time lags of at least 20 years, which is supported empirically by the analogue of oilseed rape adoption in the UK from the 1970s. This implies the need to account for time lags arising from spatial diffusion in evaluating land-use change, climate change (mitigation or adaptation) or the adoption of novel technologies. PMID:24026474

  5. Field based measurements of albedo for two candidate perennial cellulosic feedstocks and row crops in Central Illinois

    Science.gov (United States)

    Miller, J. N.; VanLoocke, A.; Bernacchi, C. J.

    2012-12-01

    The production of perennial cellulosic feedstocks for bioenergy present the potential to diversify regional economies and the national energy supply, while also serving as a climate 'regulators' due to a number of biogeochemical and biophysical differences relative to row crops. Numerous observationally and modeling based approaches, including life cycle analyses have investigated biogeochemical tradeoffs, such as increased carbon sequestration and biophysical increased water use, associated with growing cellulosic feedstocks. A less understood aspect is the biophysical changes associated with the difference in albedo, which will alter the local energy balance and could cause a local to regional cooling several times larger than that associated with offsetting carbon. To address this factor an experiment consisting of paired fields of Miscanthus and Switchgrass, two of the leading perennial cellulosic feedstock candidates, and traditional row crops was established in central Illinois. Data from the first two growing seasons indicate that this effect is most pronounced during the spring and fall as perennial biofuel crops green up earlier and senesce later than common annual row crops. The albedo of the perennials converges to that of the row crops during the growing season as the canopies develop. During the early winter, before the perennial crops are harvested, the albedo over fallow soybean and maize fields can vary greatly depending on snowfall and, to a lesser extent, soil moisture, whereas perennials show less variation. Thus, perennial biofuel crops also have the potential to buffer the local environment against short-term variations in climate. These factors should be considered when evaluating the tradeoffs and climate-regulation services associated with large-scale planting of bioenergy crops.

  6. Genome-wide association study identifies three key loci for high mesocarp oil content in perennial crop oil palm

    OpenAIRE

    Teh, Chee-Keng; Ong, Ai-Ling; Kwong, Qi-Bin; Apparow, Sukganah; Chew, Fook-Tim; Mayes, Sean; Mohamed, Mohaimi; Appleton, David; Kulaveerasingam, Harikrishna

    2016-01-01

    GWAS in out-crossing perennial crops is typically limited by insufficient marker density to account for population diversity and effects of population structure resulting in high false positive rates. The perennial crop oil palm is the most productive oil crop. We performed GWAS for oil-to-dry-mesocarp content (O/DM) on 2,045 genotyped tenera palms using 200K SNPs that were selected based on the short-range linkage disequilibrium distance, which is inherent with long breeding cycles and heter...

  7. Micrometeorological measurements over 3 years reveal differences in N2 O emissions between annual and perennial crops.

    Science.gov (United States)

    Abalos, Diego; Brown, Shannon E; Vanderzaag, Andrew C; Gordon, Robert J; Dunfield, Kari E; Wagner-Riddle, Claudia

    2016-03-01

    Perennial crops can deliver a wide range of ecosystem services compared to annual crops. Some of these benefits are achieved by lengthening the growing season, which increases the period of crop water and nutrient uptake, pointing to a potential role for perennial systems to mitigate soil nitrous oxide (N2 O) emissions. Employing a micrometeorological method, we tested this hypothesis in a 3-year field experiment with a perennial grass-legume mixture and an annual corn monoculture. Given that N2 O emissions are strongly dependent on the method of fertilizer application, two manure application options commonly used by farmers for each crop were studied: injection vs. broadcast application for the perennial; fall vs. spring application for the annual. Across the 3 years, lower N2 O emissions (P unit of fertilizer applied was 3.7, 3.1 and 1.3 times higher for the annual for each consecutive year. Differences in soil organic matter due to the contrasting root systems of these crops are probably a major factor behind the N2 O reduction. We found that a specific manure management practice can lead to increases or reductions in annual N2 O emissions depending on environmental variables. The number of freeze-thaw cycles during winter and the amount of rainfall after fertilization in spring were key factors. Therefore, general manure management recommendations should be avoided because interannual weather variability has the potential to determine if a specific practice is beneficial or detrimental. The lower N2 O emissions of perennial crops deserve further research attention and must be considered in future land-use decisions. Increasing the proportion of perennial crops in agricultural landscapes may provide an overlooked opportunity to regulate N2 O emissions. PMID:26491961

  8. Rethinking Bioenergy from an Agricultural Perspective: Ethical Issues Raised by Perennial Energy Crop and Crop Residue Production in the UK and Denmark

    DEFF Research Database (Denmark)

    Shortall, Orla

    The aim of this project is to explore the social and ethical dimensions of the agricultural production of perennial energy crop and crop residues for energy. Biomass – any living or recently living matter – is being promoted in industrialised countries as part of the transition from fossil fuels...... agriculture including the biorefinery strategy; multifunctional perennial energy crop production on environmentally marginal land; and ecologically integrated multipurpose biomass production through agroforestry production. There is also an argument which cuts across the paradigms and maintains...

  9. Comparative performance of annual and perennial energy cropping systems under different management regimes

    Energy Technology Data Exchange (ETDEWEB)

    Boehmel, Ute Constanze

    2007-07-18

    The theme of this thesis was chosen against the background of the necessary substitution of fossil fuels and the need to reduce greenhouse gas emissions. One major solution for these topics may be the energy generation from domestically produced biomass. The overall aim of this thesis was the identification of one or more efficient energy cropping systems for Central Europe. The existence of diverse production environments necessitates further diversification and the identification of several energy crops and the development of energy cropping systems suited to those diverse environments. This thesis starts with an introductory essay (chapter 1), which provides the background for renewable energy production, its features, demands and potentials, and the scientific basis of this thesis. Chapters 2 to 6 consist of five manuscripts to be published in reviewed journals (Papers I, II, IV and V) or in a multi-author book (Paper III). Subsequently, the results from all papers are discussed in a general setting (chapter 7), from which a general conclusion is formulated (chapter 8). The basis of the research formed four field experiments, which were conducted at the experimental sites Ihinger Hof, Oberer Lindenhof and Goldener Acker of the University of Hohenheim, in south-western Germany. Paper I addresses the overall objective of this thesis. Selected cropping systems for this experiment were short rotation willow, miscanthus, switchgrass, energy maize and two different crop rotation systems including winter oilseed rape, winter wheat and winter triticale with either conventional tillage or no-till. The systems were cultivated with three different nitrogen fertilizer applications. An energy balance was calculated to evaluate the biomass and energy yields of the different cropping systems. Results indicate that perennial lignocellulosic crops combine high biomass and net energy yields with low input and potential ecological impacts. Switchgrass, which produced low yields

  10. Water use efficiency of perennial and annual bioenergy crops in central Illinois

    Science.gov (United States)

    Zeri, Marcelo; Hussain, Mir Zaman; Anderson-Teixeira, Kristina J.; Delucia, Evan; Bernacchi, Carl J.

    2013-06-01

    Sustainable bioenergy production depends upon the efficiency with which crops use available water to produce biomass and store carbon belowground. Therefore, water use efficiency (WUE; productivity vs. annual evapotranspiration, ET) is a key metric of bioenergy crop performance. We evaluate WUE of three potential perennial grass bioenergy crops, Miscanthus × giganteus (miscanthus), Panicum virgatum (switchgrass), and an assemblage of prairie species (28 species), and Zea mays-Glycine max rotation, during the establishment phase in Illinois. Ecosystem WUE (EWUE; net ecosystem productivity vs. ET) was highest in miscanthus, reaching a maximum value of 12.8 ± 0.3 kg ha-1 mm-1 in the third year, followed by switchgrass (7.5 ± 0.3 kg ha-1 mm-1) and prairie (3.9 ± 0.3 kg ha-1 mm-1); the row crop was the lowest. Besides EWUE, harvest-WUE (HWUE, harvested biomass vs. ET) and net biome productivity-WUE (BWUE, calculated as net ecosystem production - harvest vs. ET) were also estimated for all crops and years. After three years of establishment, HWUE and BWUE were highest in miscanthus (9.0 ± 2 and 3.8 ± 2.9 kg ha-1 mm-1, respectively) providing a net benefit to the carbon balance, while the row crops had a negative carbon balance and a negative BWUE. BWUE for maize/soybean indicate that this ecosystem would deplete the soil carbon stocks while using the water resources. Switchgrass had the second highest BWUE, while prairie was almost neutral indicating that long-term carbon sequestration for this agro-ecosystem would be sensitive to harvest timing with an early harvest removing more biomass, and thus carbon, from the field.

  11. Comparative performance of annual and perennial energy cropping systems under different management regimes

    Energy Technology Data Exchange (ETDEWEB)

    Boehmel, Ute Constanze

    2007-07-18

    The theme of this thesis was chosen against the background of the necessary substitution of fossil fuels and the need to reduce greenhouse gas emissions. One major solution for these topics may be the energy generation from domestically produced biomass. The overall aim of this thesis was the identification of one or more efficient energy cropping systems for Central Europe. The existence of diverse production environments necessitates further diversification and the identification of several energy crops and the development of energy cropping systems suited to those diverse environments. This thesis starts with an introductory essay (chapter 1), which provides the background for renewable energy production, its features, demands and potentials, and the scientific basis of this thesis. Chapters 2 to 6 consist of five manuscripts to be published in reviewed journals (Papers I, II, IV and V) or in a multi-author book (Paper III). Subsequently, the results from all papers are discussed in a general setting (chapter 7), from which a general conclusion is formulated (chapter 8). The basis of the research formed four field experiments, which were conducted at the experimental sites Ihinger Hof, Oberer Lindenhof and Goldener Acker of the University of Hohenheim, in south-western Germany. Paper I addresses the overall objective of this thesis. Selected cropping systems for this experiment were short rotation willow, miscanthus, switchgrass, energy maize and two different crop rotation systems including winter oilseed rape, winter wheat and winter triticale with either conventional tillage or no-till. The systems were cultivated with three different nitrogen fertilizer applications. An energy balance was calculated to evaluate the biomass and energy yields of the different cropping systems. Results indicate that perennial lignocellulosic crops combine high biomass and net energy yields with low input and potential ecological impacts. Switchgrass, which produced low yields

  12. High quality reference genome of drumstick tree (Moringa oleifera Lam.), a potential perennial crop.

    Science.gov (United States)

    Tian, Yang; Zeng, Yan; Zhang, Jing; Yang, ChengGuang; Yan, Liang; Wang, XuanJun; Shi, ChongYing; Xie, Jing; Dai, TianYi; Peng, Lei; Zeng Huan, Yu; Xu, AnNi; Huang, YeWei; Zhang, JiaJin; Ma, Xiao; Dong, Yang; Hao, ShuMei; Sheng, Jun

    2015-07-01

    The drumstick tree (Moringa oleifera Lam.) is a perennial crop that has gained popularity in certain developing countries for its high-nutrition content and adaptability to arid and semi-arid environments. Here we report a high-quality draft genome sequence of M. oleifera. This assembly represents 91.78% of the estimated genome size and contains 19,465 protein-coding genes. Comparative genomic analysis between M. oleifera and related woody plant genomes helps clarify the general evolution of this species, while the identification of several species-specific gene families and positively selected genes in M. oleifera may help identify genes related to M. oleifera's high protein content, fast-growth, heat and stress tolerance. This reference genome greatly extends the basic research on M. oleifera, and may further promote applying genomics to enhanced breeding and improvement of M. oleifera. PMID:26032590

  13. High quality reference genome of drumstick tree (Moringa oleifera Lam.), a potential perennial crop.

    Science.gov (United States)

    Tian, Yang; Zeng, Yan; Zhang, Jing; Yang, ChengGuang; Yan, Liang; Wang, XuanJun; Shi, ChongYing; Xie, Jing; Dai, TianYi; Peng, Lei; Zeng Huan, Yu; Xu, AnNi; Huang, YeWei; Zhang, JiaJin; Ma, Xiao; Dong, Yang; Hao, ShuMei; Sheng, Jun

    2015-07-01

    The drumstick tree (Moringa oleifera Lam.) is a perennial crop that has gained popularity in certain developing countries for its high-nutrition content and adaptability to arid and semi-arid environments. Here we report a high-quality draft genome sequence of M. oleifera. This assembly represents 91.78% of the estimated genome size and contains 19,465 protein-coding genes. Comparative genomic analysis between M. oleifera and related woody plant genomes helps clarify the general evolution of this species, while the identification of several species-specific gene families and positively selected genes in M. oleifera may help identify genes related to M. oleifera's high protein content, fast-growth, heat and stress tolerance. This reference genome greatly extends the basic research on M. oleifera, and may further promote applying genomics to enhanced breeding and improvement of M. oleifera.

  14. Candidate perennial bioenergy grasses have a higher albedo than annual row crops in the Midwestern U.S.

    Science.gov (United States)

    The production of perennial cellulosic feedstocks for bioenergy presents the potential to diversify regional economies and the national energy supply, while also serving as climate ‘regulators’ due to a number of biogeochemical and biogeophysical differences relative to row crops. Numerous observati...

  15. Chemical control of perennial and annual weeds in herbicide resistant soybean crops.

    Science.gov (United States)

    Sarpe, N; Roibu, C; Negrila, E; Bodescu, F; Fuia, S; Popa, C; Beraru, C

    2001-01-01

    In Romania, the first tests with Roundup Ready on soybean crops were performed in 1998, on 2 soil types: a) at Teleorman Station on chernozem containing 3.5% humus, 4.5% clay b) at Brăila Station placed in Danube Meadow on alluvial soil containing 3.90% humus and 46% clay. In every locality cultivated soybean cultivar S.2254 was resistant to glyphosate. During the three years of experiments (1998-2000) the crop of soybean was infested with various species of weeds (both annual and perennial) of which the most important are: Sorghum halepense (60-80%), Echinochloa crus-galli, Setaria glauca, Amaranthus retroflexus, Solarium nigrum, Yanthium italicum, Abutilon theoprasthi, Sinapis arvensis, Datum stramonium, Polygonum persicaria, Calystegia sepium, Cirsium arvense. In 3 years of experience the best weed control and the highest soybean production were obtained in the variants treated 2 times postemergent with Roundup Ready at a dose of 3 + 3 l/ha. Similar results were also obtained in the farms of the Academy of Agricultural Forestry Sciences, where GMO soybean was cultivated on 1500 hectares.

  16. Effectiveness of Perennial Vegetation Strips in Reducing Runoff in Annual Crop Production Systems

    Science.gov (United States)

    Hernandez-Santana, V.; Zhou, X.; Helmers, M.; Asbjornsen, H.; Kolka, R. K.

    2010-12-01

    In many parts of the world, unprecedented high crop yields have been attained by conversion of native perennial grasslands to intensively managed annual cropping systems. However, these achievements have often been accompanied by significant environmental impacts with far-reaching social and economic costs. Perhaps nowhere is this situation revealed more acutely than in the Midwestern US, where landscape-scale transformation of native tallgrass prairie to rowcrop corn and soybeans has dramatically altered the hydrologic cycle, increased nutrient and sediment loss, and diminished ecosystem services. The objective of this study was to assess the potential for reducing negative impacts of rowcrop agriculture on water quality and flow by incorporating native prairie vegetation in strategic locations within conventional rowcrop agriculture. Specifically, we tested the hypothesis that small amounts of prairie vegetation strategically located in agricultural landscapes would lead to disproportionate benefits by reducing runoff and nutrient and sediment loss. The study was conducted at the Neal Smith National Wildlife Refuge (Iowa), and consisted of a fully balanced, replicated, incomplete block design whereby twelve small experimental catchments (0.43 - 3.19 ha) received four treatments consisting of varying proportions (0%, 10%, and 20%) of prairie vegetation located in different watershed positions (downslope “toe” vs. contour strips). Pre- treatment data were collected in 2005, treatments installed in 2006, and post-treatment responses monitored annually (April-October) thereafter. Volume and rate of surface runoff were measured with an H-Flume installed in each catchment, and automated ISCO samplers used to collect event-based runoff samples that were analyzed for sediment, nitrate (N), and phosphorus (P) concentration. A total of 102 rainfall events were registered during the study period (April-October, 2008 and 2009), accounting for a total rainfall amount of

  17. Ecosystem-service tradeoffs associated with switching from annual to perennial energy crops in riparian zones of the US Midwest.

    Directory of Open Access Journals (Sweden)

    Timothy D Meehan

    Full Text Available Integration of energy crops into agricultural landscapes could promote sustainability if they are placed in ways that foster multiple ecosystem services and mitigate ecosystem disservices from existing crops. We conducted a modeling study to investigate how replacing annual energy crops with perennial energy crops along Wisconsin waterways could affect a variety of provisioning and regulating ecosystem services. We found that a switch from continuous corn production to perennial-grass production decreased annual income provisioning by 75%, although it increased annual energy provisioning by 33%, decreased annual phosphorous loading to surface water by 29%, increased below-ground carbon sequestration by 30%, decreased annual nitrous oxide emissions by 84%, increased an index of pollinator abundance by an average of 11%, and increased an index of biocontrol potential by an average of 6%. We expressed the tradeoffs between income provisioning and other ecosystem services as benefit-cost ratios. Benefit-cost ratios averaged 12.06 GJ of additional net energy, 0.84 kg of avoided phosphorus pollution, 18.97 Mg of sequestered carbon, and 1.99 kg of avoided nitrous oxide emissions for every $1,000 reduction in income. These ratios varied spatially, from 2- to 70-fold depending on the ecosystem service. Benefit-cost ratios for different ecosystem services were generally correlated within watersheds, suggesting the presence of hotspots--watersheds where increases in multiple ecosystem services would come at lower-than-average opportunity costs. When assessing the monetary value of ecosystem services relative to existing conservation programs and environmental markets, the overall value of enhanced services associated with adoption of perennial energy crops was far lower than the opportunity cost. However, when we monitized services using estimates for the social costs of pollution, the value of enhanced services far exceeded the opportunity cost. This

  18. Not dead yet: the seasonal water relations of two perennial ferns during California's exceptional drought.

    Science.gov (United States)

    Baer, Alex; Wheeler, James K; Pittermann, Jarmila

    2016-04-01

    The understory of the redwood forests of California's coast harbors perennial ferns, including Polystichum munitum and Dryopteris arguta. Unusual for ferns, these species are adapted to the characteristic Mediterranean-type dry season, but the mechanisms of tolerance have not been studied. The water relations of P. munitum and D. arguta were surveyed for over a year, including measures of water potential (Ψ), stomatal conductance (gs) and frond stipe hydraulic conductivity (K). A dehydration and re-watering experiment on potted P. munitum plants corroborated the field data. The seasonal Ψ varied from 0 to below -3 MPa in both species, with gs and K generally tracking Ψ; the loss of K rarely exceeded 80%. Quantile regression analysis showed that, at the 0.1 quantile, 50% of K was lost at -2.58 and -3.84 MPa in P. munitum and D. arguta, respectively. The hydraulic recovery of re-watered plants was attributed to capillarity. The seasonal water relations of P. munitum and D. arguta are variable, but consistent with laboratory-based estimates of drought tolerance. Hydraulic and Ψ recovery following rain allows perennial ferns to survive severe drought, but prolonged water deficit, coupled with insect damage, may hamper frond survival. The legacy effects of drought on reproductive capacity and community dynamics are unknown.

  19. Carbon dioxide exchange of a perennial bioenergy crop cultivation on a mineral soil

    Science.gov (United States)

    Lind, Saara E.; Shurpali, Narasinha J.; Peltola, Olli; Mammarella, Ivan; Hyvönen, Niina; Maljanen, Marja; Räty, Mari; Virkajärvi, Perttu; Martikainen, Pertti J.

    2016-03-01

    One of the strategies to reduce carbon dioxide (CO2) emissions from the energy sector is to increase the use of renewable energy sources such as bioenergy crops. Bioenergy is not necessarily carbon neutral because of greenhouse gas (GHG) emissions during biomass production, field management and transportation. The present study focuses on the cultivation of reed canary grass (RCG, Phalaris arundinacea L.), a perennial bioenergy crop, on a mineral soil. To quantify the CO2 exchange of this RCG cultivation system, and to understand the key factors controlling its CO2 exchange, the net ecosystem CO2 exchange (NEE) was measured from July 2009 until the end of 2011 using the eddy covariance (EC) method. The RCG cultivation thrived well producing yields of 6200 and 6700 kg DW ha-1 in 2010 and 2011, respectively. Gross photosynthesis (GPP) was controlled mainly by radiation from June to September. Vapour pressure deficit (VPD), air temperature or soil moisture did not limit photosynthesis during the growing season. Total ecosystem respiration (TER) increased with soil temperature, green area index and GPP. Annual NEE was -262 and -256 g C m-2 in 2010 and 2011, respectively. Throughout the study period from July 2009 until the end of 2011, cumulative NEE was -575 g C m-2. Carbon balance and its regulatory factors were compared to the published results of a comparison site on drained organic soil cultivated with RCG in the same climate. On this mineral soil site, the RCG had higher capacity to take up CO2 from the atmosphere than on the comparison site.

  20. Using stable isotopes to characterize differential depth of water uptake based on environmental conditions in perennial biofuel and traditional annual crops

    Science.gov (United States)

    Miller, J. N.; Nystrom, R.; Bernacchi, C.

    2013-12-01

    Global climate change related to fossil fuel consumption coupled with the necessity for secure, cost-effective, and renewable domestic energy is continuing to drive the development of a bioenergy industry. Numerous second-generation biofuel crops have been identified that hold promise as sustainable feedstocks for the industry, including perennial grasses that utilize the highly water and energy efficient C4 photosynthetic pathway. Among the perennial grasses, miscanthus (Miscanthus × giganteus) and switchgrass (Panicum virgatum) stand out as having high biomass, minimal maintenance, low nutrient input requirements, and positive environmental benefits. These grasses are able to withstand a wide range of growing season temperatures and precipitation regimes, particularly in reference to the annual row crops that they are likely to replace. During the drought of 2012 traditional row crops suffered major reductions in yield whereas the perennial grasses retained relatively high biomass yields. We hypothesize that this is due to the ability of the perennial grasses to access water from deeper soil water relative to the annual row crops. To test this hypothesis, we use isotopic techniques to determine the soil depth from which the various species obtain water. Data from summer 2013 suggests that the perennial grasses preferentially use surface water when available but can extract water from depths that the annual row crops are unable to reach. These results indicate that perennial grasses, with deeper roots, will likely sustain growth under conditions when annual row crops are unable.

  1. Genome-wide association study identifies three key loci for high mesocarp oil content in perennial crop oil palm

    Science.gov (United States)

    Teh, Chee-Keng; Ong, Ai-Ling; Kwong, Qi-Bin; Apparow, Sukganah; Chew, Fook-Tim; Mayes, Sean; Mohamed, Mohaimi; Appleton, David; Kulaveerasingam, Harikrishna

    2016-01-01

    GWAS in out-crossing perennial crops is typically limited by insufficient marker density to account for population diversity and effects of population structure resulting in high false positive rates. The perennial crop oil palm is the most productive oil crop. We performed GWAS for oil-to-dry-mesocarp content (O/DM) on 2,045 genotyped tenera palms using 200K SNPs that were selected based on the short-range linkage disequilibrium distance, which is inherent with long breeding cycles and heterogeneous breeding populations. Eighty loci were significantly associated with O/DM (p ≤ 10−4) and three key signals were found. We then evaluated the progeny of a Deli x AVROS breeding trial and a 4% higher O/DM was observed amongst those having the beneficial genotypes at two of the three key loci (p < 0.05). We have initiated MAS and large-scale planting of elite dura and pisifera parents to generate the new commercial tenera palms with higher O/DM potential. PMID:26743827

  2. Genome-wide association study identifies three key loci for high mesocarp oil content in perennial crop oil palm.

    Science.gov (United States)

    Teh, Chee-Keng; Ong, Ai-Ling; Kwong, Qi-Bin; Apparow, Sukganah; Chew, Fook-Tim; Mayes, Sean; Mohamed, Mohaimi; Appleton, David; Kulaveerasingam, Harikrishna

    2016-01-01

    GWAS in out-crossing perennial crops is typically limited by insufficient marker density to account for population diversity and effects of population structure resulting in high false positive rates. The perennial crop oil palm is the most productive oil crop. We performed GWAS for oil-to-dry-mesocarp content (O/DM) on 2,045 genotyped tenera palms using 200K SNPs that were selected based on the short-range linkage disequilibrium distance, which is inherent with long breeding cycles and heterogeneous breeding populations. Eighty loci were significantly associated with O/DM (p ≤ 10(-4)) and three key signals were found. We then evaluated the progeny of a Deli x AVROS breeding trial and a 4% higher O/DM was observed amongst those having the beneficial genotypes at two of the three key loci (p < 0.05). We have initiated MAS and large-scale planting of elite dura and pisifera parents to generate the new commercial tenera palms with higher O/DM potential. PMID:26743827

  3. Plant growth regulation in seed crops of perennial ryegrass (Lolium perenne L)

    DEFF Research Database (Denmark)

    Boelt, Birte; Lemaire, Charles; Abel, Simon;

    2016-01-01

    Seed yield components were recorded in plants of perennial ryegrass cv. Calibra a medium late, forage type (4n) in a two factorial block design with Nitrogen (N) and plant growth regulator (PGR) application in 2014 and 2015 at Aarhus University (AU), Flakkebjerg. For each plant, reproductive...

  4. Comparison of soil microbial respiration and carbon turnover under perennial and annual biofuel crops in two agricultural soils

    Science.gov (United States)

    Szymanski, L. M.; Marin-Spiotta, E.; Sanford, G. R.; Jackson, R. D.; Heckman, K. A.

    2015-12-01

    Bioenergy crops have the potential to provide a low carbon-intensive alternative to fossil fuels. More than a century of agricultural research has shown that conventional cropping systems can reduce soil organic matter (SOM) reservoirs, which cause long-term soil nutrient loss and C release to the atmosphere. In the face of climate change and other human disruptions to biogeochemical cycles, identifying biofuel crops that can maintain or enhance soil resources is desirable for the sustainable production of bioenergy. The objective of our study was to compare the effects of four biofuel crop treatments on SOM dynamics in two agricultural soils: Mollisols at Arlington Agricultural Research Station in Wisconsin and Alfisols at Kellogg Biological Station in Michigan, USA. We used fresh soils collected in 2013 and archived soils from 2008 to measure the effects of five years of crop management. Using a one-year long laboratory soil incubation coupled with a regression model and radiocarbon measurements, we separated soils into three SOM pools and their corresponding C turnover times. We found that the active pool, or biologically available C, was more sensitive to management and is an earlier indicator of changes to soil C dynamics than bulk soil C measurements. There was no effect of treatment on the active pool size at either site; however, the percent C in the active pool decreased, regardless of crop type, in surface soils with high clay content. At depth, the response of the slow pool differed between annual and perennial cropping systems. The distribution of C among SOM fractions varied between the two soil types, with greater C content associated with the active fraction in the coarser textured-soil and greater C content associated with the slow-cycling fraction in the soils with high clay content. These results suggest that the effects of bioenergy crops on soil resources will vary geographically, with implications for the carbon-cost of biocrop production.

  5. PERPHECLIM ACCAF Project - Perennial fruit crops and forest phenology evolution facing climatic changes

    Science.gov (United States)

    Garcia de Cortazar-Atauri, Iñaki; Audergon, Jean Marc; Bertuzzi, Patrick; Anger, Christel; Bonhomme, Marc; Chuine, Isabelle; Davi, Hendrik; Delzon, Sylvain; Duchêne, Eric; Legave, Jean Michel; Raynal, Hélène; Pichot, Christian; Van Leeuwen, Cornelis; Perpheclim Team

    2015-04-01

    Phenology is a bio-indicator of climate evolutions. Measurements of phenological stages on perennial species provide actually significant illustrations and assessments of the impact of climate change. Phenology is also one of the main key characteristics of the capacity of adaptation of perennial species, generating questions about their consequences on plant growth and development or on fruit quality. Predicting phenology evolution and adaptative capacities of perennial species need to override three main methodological limitations: 1) existing observations and associated databases are scattered and sometimes incomplete, rendering difficult implementation of multi-site study of genotype-environment interaction analyses; 2) there are not common protocols to observe phenological stages; 3) access to generic phenological models platforms is still very limited. In this context, the PERPHECLIM project, which is funded by the Adapting Agriculture and Forestry to Climate Change Meta-Program (ACCAF) from INRA (French National Institute of Agronomic Research), has the objective to develop the necessary infrastructure at INRA level (observatories, information system, modeling tools) to enable partners to study the phenology of various perennial species (grapevine, fruit trees and forest trees). Currently the PERPHECLIM project involves 27 research units in France. The main activities currently developed are: define protocols and observation forms to observe phenology for various species of interest for the project; organizing observation training; develop generic modeling solutions to simulate phenology (Phenological Modelling Platform and modelling platform solutions); support in building research projects at national and international level; develop environment/genotype observation networks for fruit trees species; develop an information system managing data and documentation concerning phenology. Finally, PERPHECLIM project aims to build strong collaborations with public

  6. Weather-based forecasts of California crop yields

    Energy Technology Data Exchange (ETDEWEB)

    Lobell, D B; Cahill, K N; Field, C B

    2005-09-26

    Crop yield forecasts provide useful information to a range of users. Yields for several crops in California are currently forecast based on field surveys and farmer interviews, while for many crops official forecasts do not exist. As broad-scale crop yields are largely dependent on weather, measurements from existing meteorological stations have the potential to provide a reliable, timely, and cost-effective means to anticipate crop yields. We developed weather-based models of state-wide yields for 12 major California crops (wine grapes, lettuce, almonds, strawberries, table grapes, hay, oranges, cotton, tomatoes, walnuts, avocados, and pistachios), and tested their accuracy using cross-validation over the 1980-2003 period. Many crops were forecast with high accuracy, as judged by the percent of yield variation explained by the forecast, the number of yields with correctly predicted direction of yield change, or the number of yields with correctly predicted extreme yields. The most successfully modeled crop was almonds, with 81% of yield variance captured by the forecast. Predictions for most crops relied on weather measurements well before harvest time, allowing for lead times that were longer than existing procedures in many cases.

  7. Rust disease continues to threaten California garlic crop

    OpenAIRE

    Koike, Steven T.; Smith, Richard; Davis, R. Michael; Nunez, J. Joe; Voss, Ron E.

    2001-01-01

    In 1998, following the very wet EI Niño weather event, a devastating outbreak of rust disease severely damaged the garlic crop in California. The disease also occurred in 1999 and 2000, indicating that rust may have developed into an annual problem. We identified the pathogen as Puccinia allii. In our study, it infected allium crops such as garlic, onion and chives, but not leek, elephant garlic or shallot. Currently registered materials did not control the disease, but tebuconazole (Folicur)...

  8. Multi-farm economic analysis of perennial energy crops in Central Greece, taking into account the CAP reform

    International Nuclear Information System (INIS)

    This study analyses farm level economic impacts of biomass production from perennial crops including Arundo donax L. (arundo), Miscanthus x giganteus (miscanthus), Panicum virgatum L. (switchgrass) and Cynara cardunculus L. (cardoon). Regional biomass supply curves are estimated with a dynamic, multi-farm, mathematical programming model. Micro-economic data for the model are generated from farm surveys covering 52 farms containing a total of 400 parcels, in Central Greece. The study also examines the potential effects of the Common Agricultural Policy reform in 2003 on regional biomass supply. Simulations show that the policy reform toward decoupled subsidies lowers the cost of biomass between 15 and 25 euro per tonne. Switchgrass appears to be the most attractive option, followed by cardoon and miscanthus. Due to high specific machinery cost, arundo is never preferred. Relative to the agricultural policy setting of Agenda 2000, the biomass potential increases more for farms of small economic size and farms with a higher share of cotton. (author)

  9. Comparing annual and perennial crops for bioenergy production - influence on nitrate leaching and energy balance

    DEFF Research Database (Denmark)

    Pugesgaard, Siri; Schelde, Kirsten; Ugilt Larsen, Søren;

    2015-01-01

    concentration in soil water was measured below winter wheat, grass-clover and willow during three growing seasons. Crop water balances were modelled to estimate the amount of nitrate leached per hectare. In addition, dry matter yields and nitrogen (N) yields were measured, and N balances and energy balances......Production of energy crops is promoted as a means to mitigate global warming by decreasing dependency on fossil energy. However, agricultural production of bioenergy can have various environmental effects depending on the crop and production system. In a field trial initiated in 2008, nitrate...... was also measured in an old willow crop established in 1996 from which N leaching ranged from 6 to 27 kg ha−1 yr−1. Dry matter yields ranged between 5.9 and 14.8 Mg yr−1 with lowest yield in the newly established willow and the highest yield harvested in grass-clover. Grass-clover gave the highest net...

  10. Strip cropping of alternating perennial grass–clover and annual rye–vetch intercrops when grown within an organic farming system

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, Henrik; Johansen, A.; Carter, Mette Sustmann;

    2012-01-01

    interactions. Less soil water content below the perennial strip indicated greater water uptake, than below the annual strips. Unfortunately, the present strip cropping system did not possess the right balance of co-existence and complementarity. However, from a practical point of view the system was manageable...

  11. C4 bioenergy crops for cool climates, with special emphasis on perennial C4 grasses.

    Science.gov (United States)

    Sage, Rowan F; de Melo Peixoto, Murilo; Friesen, Patrick; Deen, Bill

    2015-07-01

    There is much interest in cultivating C4 perennial plants in northern climates where there is an abundance of land and a potential large market for biofuels. C4 feedstocks can exhibit superior yields to C3 alternatives during the long warm days of summer at high latitude, but their summer success depends on an ability to tolerate deep winter cold, spring frosts, and early growth-season chill. Here, we review cold tolerance limits in C4 perennial grasses. Dozens of C4 species are known from high latitudes to 63 °N and elevations up to 5200 m, demonstrating that C4 plants can adapt to cold climates. Of the three leading C4 grasses being considered for bioenergy production in cold climates--Miscanthus spp., switchgrass (Panicum virgatum), and prairie cordgrass (Spartina pectinata)--all are tolerant of cool temperatures (10-15 °C), but only cordgrass tolerates hard spring frosts. All three species overwinter as dormant rhizomes. In the productive Miscanthus×giganteus hybrids, exposure to temperatures below -3 °C to -7 °C will kill overwintering rhizomes, while for upland switchgrass and cordgrass, rhizomes survive exposure to temperatures above -20 °C to -24 °C. Cordgrass emerges earlier than switchgrass and M. giganteus genotypes, but lacks the Miscanthus growth potential once warmer days of late spring arrive. To enable C4-based bioenergy production in colder climates, breeding priorities should emphasize improved cold tolerance of M.×giganteus, and enhanced productivity of switchgrass and cordgrass. This should be feasible in the near future, because wild populations of each species exhibit a diverse range of cold tolerance and growth capabilities.

  12. Nitrogen Fertilization Effects on Productivity and Nitrogen Loss in Three Grass-Based Perennial Bioenergy Cropping Systems.

    Science.gov (United States)

    Duran, Brianna E L; Duncan, David S; Oates, Lawrence G; Kucharik, Christopher J; Jackson, Randall D

    2016-01-01

    Nitrogen (N) fertilization can greatly improve plant productivity but needs to be carefully managed to avoid harmful environmental impacts. Nutrient management guidelines aimed at reducing harmful forms of N loss such as nitrous oxide (N2O) emissions and nitrate (NO3(-)) leaching have been tailored for many cropping systems. The developing bioenergy industry is likely to make use of novel cropping systems, such as polycultures of perennial species, for which we have limited nutrient management experience. We studied how a switchgrass (Panicum virgatum) monoculture, a 5-species native grass mixture and an 18-species restored prairie responded to annual fertilizer applications of 56 kg N ha(-1) in a field-scale agronomic trial in south-central Wisconsin over a 2-year period. We observed greater fertilizer-induced N2O emissions and sub-rooting zone NO3(-) concentrations in the switchgrass monoculture than in either polyculture. Fertilization increased aboveground net primary productivity in the polycultures, but not in the switchgrass monoculture. Switchgrass was generally more productive, while the two polycultures did not differ from each other in productivity or N loss. Our results highlight differences between polycultures and a switchgrass monoculture in responding to N fertilization.

  13. Constraints to obtaining consistent annual yields in perennial tree crops. I: Heavy fruit load dominates over vegetative growth.

    Science.gov (United States)

    Smith, Harley M; Samach, Alon

    2013-06-01

    Farmers lack effective methods to achieve and maintain stable production from year to year in many commercial fruit crops. Annual fruit yield within a region often alternates between high and low fruit load and is termed alternate bearing. The underlying cause of alternate bearing is the negative impact of high fruit load on vegetative growth and next year's flowering. In this review, we emphasize common responses of diverse perennials to heavy crop load. We present botanical, ecological and horticultural perspectives on irregular bearing. The later part of this review focuses on understanding how high fruit load dominates over vegetative growth. We discuss sink strengths and putative mobile signals (hormones), perhaps seed-derived. We highlight gaps in current understanding of alternate bearing, and discuss new approaches to better understand fruit load dominance. Assuming the effect of high fruit load may be related to other mechanisms of sink partitioning, other forms of dominance are presented such as apical, first fruit and king fruit dominance. Dominance seems to be enforced, in independent cases through the establishment of a polar auxin transport system from the stronger sink. Once established this somehow perturbs the transport of auxin out of weaker sinks. Possibly, fruit derived auxin may alter the polar auxin transport system of the shoot to inhibit shoot growth.

  14. Genomic approaches to selection in outcrossing perennials: focus on essential oil crops.

    Science.gov (United States)

    Kainer, David; Lanfear, Robert; Foley, William J; Külheim, Carsten

    2015-12-01

    The yield of essential oil in commercially harvested perennial species (e.g. 'Oil Mallee' eucalypts, Tea Trees and Hop) is dependent on complex quantitative traits such as foliar oil concentration, biomass and adaptability. These often show large natural variation and some are highly heritable, which has enabled significant gains in oil yield via traditional phenotypic recurrent selection. Analysis of transcript abundance and allelic diversity has revealed that essential oil yield is likely to be controlled by large numbers of quantitative trait loci that range from a few of medium/large effect to many of small effect. Molecular breeding techniques that exploit this information could increase gains per unit time and address complications of traditional breeding such as genetic correlations between key traits and the lower heritability of biomass. Genomic selection (GS) is a technique that uses the information from markers genotyped across the whole genome in order to predict the phenotype of progeny well before they reach maturity, allowing selection at an earlier age. In this review, we investigate the feasibility of genomic selection (GS) for the improvement of essential oil yield. We explore the challenges facing breeders selecting for oil yield, and how GS might deal with them. We then assess the factors that affect the accuracy of genomic estimated breeding values, such as linkage disequilibrium (LD), heritability, relatedness and the genetic architecture of desirable traits. We conclude that GS has the potential to significantly improve the efficiency of selection for essential oil yield. PMID:26239409

  15. Effects of dairy manure management in annual and perennial cropping systems on soil microbial communities associated with in situ N2O fluxes

    Science.gov (United States)

    Dunfield, Kari; Thompson, Karen; Bent, Elizabeth; Abalos, Diego; Wagner-Riddle, Claudia

    2016-04-01

    Liquid dairy manure (LDM) application and ploughing events may affect soil microbial community functioning differently between perennial and annual cropping systems due to plant-specific characteristics stimulating changes in microbial community structure. Understanding how these microbial communities change in response to varied management, and how these changes relate to in situ N2O fluxes may allow the creation of predictive models for use in the development of best management practices (BMPs) to decrease nitrogen (N) losses through choice of crop, plough, and LDM practices. Our objectives were to contrast changes in the population sizes and community structures of genes associated with nitrifier (amoA, crenamoA) and denitrifier (nirK, nirS, nosZ) communities in differently managed annual and perennial fields demonstrating variation in N2O flux, and to determine if differences in these microbial communities were linked to the observed variation in N2O fluxes. Soil was sampled in 2012 and in 2014 in a 4-ha spring-applied LDM grass-legume (perennial) plot and two 4-ha corn (annual) treatments under fall or spring LDM application. Soil DNA was extracted and used to target N-cycling genes via qPCR (n=6) and for next-generation sequencing (Illumina Miseq) (n=3). Significantly higher field-scale N2O fluxes were observed in the annual plots compared to the perennial system; however N2O fluxes increased after plough down of the perennial plot. Nonmetric multidimensional scaling (NMS) indicated differences in N-cycling communities between annual and perennial cropping systems, and some communities became similar between annual and perennial plots after ploughing. Shifts in these communities demonstrated relationships with agricultural management, which were associated with differences in N2O flux. Indicator species analysis was used to identify operational taxonomic units (OTUs) most responsible for community shifts related to management. Nitrifying and denitrifying soil

  16. Testing an Irrigation Decision Support Tool for California Specialty Crops

    Science.gov (United States)

    Johnson, L.; Cahn, M.; Benzen, S.; Zaragoza, I.; Murphy, L.; Melton, F. S.; Martin, F.; Quackenbush, A.; Lockhart, T.

    2015-12-01

    Estimation of crop evapotranspiration supports efficiency of irrigation water management, which in turn can mitigate nitrate leaching, groundwater depletion, and provide energy savings. Past research in California and elsewhere has revealed strong relationships between photosynthetically active vegetation fraction (Fc) and crop evapotranspiration (ETc). Additional research has shown the potential of monitoring Fc by satellite remote sensing. The U.C. Cooperative Extension developed and operates CropManage (CM) as on-line database irrigation (and nitrogen) scheduling tool. CM accounts for the rapid growth and typically brief cycle of cool-season vegetables, where Fc and fraction of reference ET can change daily during canopy development. The model automates crop water requirement calculations based on reference ET data collected by California Dept. Water Resources. Empirically-derived equations are used to estimate daily Fc time-series for a given crop type primarily as a function of planting date and expected harvest date. An application programming interface (API) is under development to provide a check on modeled Fc of current crops and facilitate CM expansion to new crops. The API will enable CM to extract field scale Fc observations from NASA's Satellite Irrigation Management Support (SIMS). SIMS is mainly Landsat based and currently monitors Fc over about 8 million irrigation acres statewide, with potential for adding data from ESA/Sentinel for improved temporal resolution. In the current study, a replicated irrigation trial was performed on romaine lettuce at the USDA Agricultural Research Station in Salinas, CA. CropManage recommendations were used to guide water treatments by drip irrigation at 50%, 75%, 100% ETc replacement levels, with an added treatment at 150% ET representing grower standard practice. Experimental results indicate that yields from the 100% and 150% treatments were not significantly different and were in-line with industry average, while

  17. Using Imaging Spectrometry to Identify Crops in California's Central Valley

    Science.gov (United States)

    Shivers, S.; Roberts, D. A.

    2015-12-01

    With a growing global population, limited resources and a changing climate, understanding and monitoring the distribution of our food and water resources is essential to their sustainability. Regional food yield estimates and water resource accounting are dependent upon accurate agricultural records. Crop mapping provides farmers, managers, and policymakers the information necessary to anticipate annual food supplies and water demands by better understanding the distribution of species. While on the ground crop accounting usually happens yearly at the county level and requires significant time and labor inputs, remote sensing has the potential to map crops and monitor their health over a greater spatial area with more frequent time intervals. Specifically, imaging spectrometers have the capability to produce imagery at high spectral and spatial resolutions, which may allow for differentiation of crops at the field-level scale. In this research 14 crop species and soil were classified in Kern County, California using canonical discriminant analysis (CDA) and Multiple Endmember Spectral Mixture Analysis (MESMA) on airborne visible/infrared imaging spectrometer (AVIRIS) imagery from June 2013. Imagery was then degraded to Landsat spectral resolution and reclassified for comparison. Results with the AVIRIS imagery show an overall accuracy of 69.0% using MESMA and 89.4% using CDA with nine out of fourteen crop species showing user and producer errors under ten percent. Lower accuracy was found for OLI data. This research illustrates great potential for field-level crop mapping with imaging spectrometry.

  18. Bee species diversity enhances productivity and stability in a perennial crop.

    Directory of Open Access Journals (Sweden)

    Shelley R Rogers

    Full Text Available Wild bees provide important pollination services to agroecoystems, but the mechanisms which underlie their contribution to ecosystem functioning--and, therefore, their importance in maintaining and enhancing these services-remain unclear. We evaluated several mechanisms through which wild bees contribute to crop productivity, the stability of pollinator visitation, and the efficiency of individual pollinators in a highly bee-pollination dependent plant, highbush blueberry. We surveyed the bee community (through transect sampling and pan trapping and measured pollination of both open- and singly-visited flowers. We found that the abundance of managed honey bees, Apis mellifera, and wild-bee richness were equally important in describing resulting open pollination. Wild-bee richness was a better predictor of pollination than wild-bee abundance. We also found evidence suggesting pollinator visitation (and subsequent pollination are stabilized through the differential response of bee taxa to weather (i.e., response diversity. Variation in the individual visit efficiency of A. mellifera and the southeastern blueberry bee, Habropoda laboriosa, a wild specialist, was not associated with changes in the pollinator community. Our findings add to a growing literature that diverse pollinator communities provide more stable and productive ecosystem services.

  19. Planning and costing adaptation of perennial crop systems to climate change: Coffee and banana in Rwanda

    Energy Technology Data Exchange (ETDEWEB)

    Ngabitsinze, Jean Chrysostome; Mukashema, Adrie; Ikirezi, Mireille; Niyitanga, Fidele

    2011-10-15

    The Rwandan economy is mainly based on agriculture. Since agricultural production in Rwanda depends almost exclusively on the quality of the rainy season and specific temperature ranges, it makes the country particularly vulnerable to climate variability and change. The study objective of evaluating and costing the most suitable climate change adaptation measures for this geographic context responds to the Rwandan Economic Development and Poverty Reduction Strategy, 2008-2012 (EDPRS) (MINECOFIN 2007), in which climate change and its adverse impacts were recently identified as a high priority. This study has particularly focused on coffee and banana farming systems and aimed at analysing shocks due to climate change from farmer to policymaker perspectives. The study found that in the last 30 years, Rwanda has experienced a series of climate fluctuations in terms of frequency, intensity, and persistence of existing extremes. Heavy rains, storms, heatwaves and droughts are the observed manifestations of climate change in specific areas of Rwanda. Changing weather patterns have an adverse impact on the country's agricultural production and thus on the country's GDP. Adaptation options for Rwanda include the following efficiency-enhancing agricultural interventions: 1. Adaption of crop calendars to new climate patterns (more effective distribution of inputs such as fertilizers and pesticides). 2. Investments in farming equipment. 3. Improvement of extension services and research. 4. Restructuring of the institutional frameworks and development plans. Integrated water resources management (IWRM); setting up information systems for early warning systems and rapid intervention mechanisms; intense agri-pastoral activities; and research on climate-resilient varieties were identified as primary requirements for agricultural adaption to climate change. In addition, developing alternative energy sources (e.g., substituting firewood) and the promotion of non

  20. Annual maize and perennial grass-clover strip cropping for increased resource use efficiency and productivity using organic farming practice as a model

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, Henrik; Johansen, Anders; Carter, Mette Sustmann;

    2013-01-01

    A cropping system was designed to fulfill the increasing demand for biomass for food and energy without decreasing long term soil fertility. A field experiment was carried out including alternating strips of annual maize (Zea mays L.) and perennial ryegrass (Lolium perenne L.) – clover (Trifolium...... of the grass to compete for soil mineral N. Maize yields were clearly associated with N fertilizer application. When fertilizer N was applied through slurry or anaerobic digested slurry maize yields was increasing with up to 100% equivalent to 1200g carbon (C) m−2 or 35MJm−2. However, the same relative growth...... reduction was found when grown in close proximity to the grass-clover strip. If slurry is available maize secures an efficient N uptake, however, long-term effects of maize cropping and biomass removal on soil quality is of concern. The present strip cropping system did not possess the right balance of co...

  1. Super-races are not likely to dominate a fungal population within a life time of a perennial crop plantation of cultivar mixtures: a simulation study

    Directory of Open Access Journals (Sweden)

    Xu Xiangming

    2012-08-01

    Full Text Available Abstract Background Deployment of cultivars with different resistance in mixtures is one means to manage plant diseases and prolong the life of resistance genes. One major concern in adopting mixtures is the development of ‘super-races’ that can overcome many resistance genes present in the mixture. A stochastic simulation model was developed to study the dynamics of virulence alleles in two-cultivar mixtures of perennial crops, focusing on the effects of cost of virulence and pathogen reproduction mechanism. The simulated mechanism of virulence has characteristics of both major and minor genes. Results Random genetic drift due to repeated population crashes during the overwintering phase led to fixation of a single fungal genotype (in terms of its virulence, often within 100 seasons. Overall, cost of virulence is most important in determining the virulence dynamics under the present model formulation. With cost of virulence incorporated, nearly all simulation runs ended up with a single fungal genotype that can infect only one of the two cultivars. In absence of cost of virulence, most of the simulation runs ended up with fungal genotypes that can infect both host cultivars but in many cases do not contain the maximum possible number of virulence alleles due to random drift. A minimum of 20% sexual reproduction between strains from different cultivars is necessary to ensure that the final fixed strains are able to infect both cultivars. Although the number of virulence alleles in the final genotype and the time to fixation are affected by simulation factors, most of the variability was among replicate simulation runs (i.e. stochastic in nature. The time to fixation is generally long relative to cropping cycles. Conclusions A single fungal genotype will dominate a population due to the bottleneck in overwintering with cost of virulence primarily determining whether the dominant genotype can infect both cultivars. However, the dominant

  2. Growth and Metal Accumulation of an Alyssum murale Nickel Hyperaccumulator Ecotype Co-cropped with Alyssum montanum and Perennial Ryegrass in Serpentine Soil.

    Science.gov (United States)

    Broadhurst, Catherine L; Chaney, Rufus L

    2016-01-01

    The genus Alyssum (Brassicaceae) contains Ni hyperaccumulators (50), many of which can achieve 30 g kg(-1) Ni in dry leaf. Some Alyssum hyperaccumulators are viable candidates for commercial Ni phytoremediation and phytomining technologies. It is not known whether these species secrete organic and/or amino acids into the rhizosphere to solubilize Ni, or can make use of such acids within the soil to facilitate uptake. It has been hypothesized that in fields with mixed plant species, mobilization of metals by phytosiderophores secreted by Graminaceae plants could affect Alyssum Ni, Fe, Cu, and Mn uptake. We co-cropped the Ni hyperaccumulator Alyssum murale, non-hyperaccumulator A. montanum and perennial ryegrass in a natural serpentine soil. All treatments had standard inorganic fertilization required for ryegrass growth and one treatment was compost amended. After 4 months A. murale leaves and stems contained 3600 mg kg(-1) Ni which did not differ significantly with co-cropping. Overall Ni and Mn concentrations were significantly higher in A. murale than in A. montanum or L. perenne. Copper was not accumulated by either Alyssum species, but L. perenne accumulated up to 10 mg kg(-1). A. montanum could not compete with either A. murale or ryegrass, and neither Alyssum species survived in the compost-amended soil. Co-cropping with ryegrass reduced Fe and Mn concentrations in A. murale but not to the extent of either increasing Ni uptake or affecting plant nutrition. The hypothesized Alyssum Ni accumulation in response to phytosiderophores secreted by co-cropped grass did not occur. Our data do not support increased mobilization of Mn by a phytosiderophore mechanism either, but the converse: mobilization of Mn by the Alyssum hyperaccumulator species significantly increased Mn levels in L. perenne. Tilling soil to maximize root penetration, adequate inorganic fertilization and appropriate plant densities are more important for developing efficient phytoremediation and

  3. Growth and Metal Accumulation of an Alyssum murale Nickel Hyperaccumulator Ecotype Co-cropped with Alyssum montanum and Perennial Ryegrass in Serpentine Soil

    Directory of Open Access Journals (Sweden)

    Catherine Leigh Broadhurst

    2016-04-01

    Full Text Available The genus Alyssum (Brassicaceae contains Ni hyperaccumulators (50, many of which can achieve 30 g kg-1 Ni in dry leaf. Some Alyssum hyperaccumulators are viable candidates for commercial Ni phytoremediation and phytomining technologies. It is not known whether these species secrete organic and/or amino acids into the rhizosphere to solubilize Ni, or can make use of such acids within the soil to facilitate uptake. It has been hypothesized that in fields with mixed plant species, mobilization of metals by phytosiderophores secreted by Graminaceae plants could affect Alyssum Ni, Fe, Cu and Mn uptake.We co-cropped the Ni hyperaccumulator Alyssum murale, non-hyperaccumulator A. montanum and perennial ryegrass in a natural serpentine soil. All treatments had standard inorganic fertilization required for ryegrass growth and one treatment was compost amended. After 4 months A. murale leaves and stems contained 3600 mg kg-1 Ni which did not differ significantly with co-cropping. Overall Ni and Mn concentrations were significantly higher in A. murale than in A. montanum or L. perenne. Copper was not accumulated by either Alyssum species, but L. perenne accumulated up to 10 mg kg-1. A. montanum could not compete with either A. murale or ryegrass, and neither Alyssum species survived in the compost-amended soil. Co-cropping with ryegrass reduced Fe and Mn concentrations in A. murale but not to the extent of either increasing Ni uptake or affecting plant nutrition. The hypothesized Alyssum Ni accumulation in response to phytosiderophores secreted by co-cropped grass did not occur. Our data do not support increased mobilization of Mn by a phytosiderophore mechanism either, but the converse: mobilization of Mn by the Alyssum hyperaccumulator species significantly increased Mn levels in L. perenne. Tilling soil to maximize root penetration, adequate inorganic fertilization and appropriate plant densities are more important for developing efficient

  4. The California Biomass Crop Adoption Model estimates biofuel feedstock crop production across diverse agro-ecological zones within the state, under different future climates

    Science.gov (United States)

    Kaffka, S.; Jenner, M.; Bucaram, S.; George, N.

    2012-12-01

    Both regulators and businesses need realistic estimates for the potential production of biomass feedstocks for biofuels and bioproducts. This includes the need to understand how climate change will affect mid-tem and longer-term crop performance and relative advantage. The California Biomass Crop Adoption Model is a partial mathematical programming optimization model that estimates the profit level needed for new crop adoption, and the crop(s) displaced when a biomass feedstock crop is added to the state's diverse set of cropping systems, in diverse regions of the state. Both yield and crop price, as elements of profit, can be varied. Crop adoption is tested against current farmer preferences derived from analysis of 10 years crop production data for all crops produced in California, collected by the California Department of Pesticide Regulation. Analysis of this extensive data set resulted in 45 distinctive, representative farming systems distributed across the state's diverse agro-ecological regions. Estimated yields and water use are derived from field trials combined with crop simulation, reported elsewhere. Crop simulation is carried out under different weather and climate assumptions. Besides crop adoption and displacement, crop resource use is also accounted, derived from partial budgets used for each crop's cost of production. Systematically increasing biofuel crop price identified areas of the state where different types of crops were most likely to be adopted. Oilseed crops like canola that can be used for biodiesel production had the greatest potential to be grown in the Sacramento Valley and other northern regions, while sugar beets (for ethanol) had the greatest potential in the northern San Joaquin Valley region, and sweet sorghum in the southern San Joaquin Valley. Up to approximately 10% of existing annual cropland in California was available for new crop adoption. New crops are adopted if the entire cropping system becomes more profitable. In

  5. Historical effects of temperature and precipitation on California crop yields

    Energy Technology Data Exchange (ETDEWEB)

    Lobell, D.B. [Energy and Environment Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Cahill, K.N. [Interdisciplinary Graduate Program in Environment and Resources, Stanford University, Stanford, CA 94305 (United States); Field, C.B. [Department of Global Ecology, Carnegie Institution, Stanford, CA 94305 (United States)

    2007-03-15

    For the 1980-2003 period, we analyzed the relationship between crop yield and three climatic variables (minimum temperature, maximum temperature, and precipitation) for 12 major Californian crops: wine grapes, lettuce, almonds, strawberries, table grapes, hay, oranges, cotton, tomatoes, walnuts, avocados, and pistachios. The months and climatic variables of greatest importance to each crop were used to develop regressions relating yield to climatic conditions. For most crops, fairly simple equations using only 2-3 variables explained more than two-thirds of observed yield variance. The types of variables and months identified suggest that relatively poorly understood processes such as crop infection, pollination, and dormancy may be important mechanisms by which climate influences crop yield. Recent climatic trends have had mixed effects on crop yields, with orange and walnut yields aided, avocado yields hurt, and most crops little affected by recent climatic trends. Yield-climate relationships can provide a foundation for forecasting crop production within a year and for projecting the impact of future climate changes.

  6. Estimation of actual evapotranspiration of Mediterranean perennial crops by means of remote-sensing based surface energy balance models

    OpenAIRE

    G. Rallo; Provenzano, G; Pumo, D.; Iovino, M.; G. D'Urso; C. Cammalleri; Ciraolo, G.; Agnese, C.; F. Blanda; M. Minacapilli

    2009-01-01

    Actual evapotranspiration from typical Mediterranean crops has been assessed in a Sicilian study area by using surface energy balance (SEB) and soil-water balance models. Both modelling approaches use remotely sensed data to estimate evapotranspiration fluxes in a spatially distributed way. The first approach exploits visible (VIS), near-infrared (NIR) and thermal (TIR) observations to solve the surface energy balance equation whereas the soil-water balance model uses only VIS-NIR data to det...

  7. Transpiration and stomatal resistance variations of perennial tropical crops under soil water availability conditions and water deficit

    Directory of Open Access Journals (Sweden)

    José Ozinaldo Alves de Sena

    2007-03-01

    Full Text Available During the dry and rainy seasons, determinations of stomatal resistance and transpiration of five tropical crops were carried out: guarana (Paullinia cupana Kunth, coffee (Coffea arabica L., cashew (Anacardium occidentale L., guava (Psidium guajava L. and rubber (Hevea brasiliensis Muell. - Arg. trees. Experimental design was done at randomized complete blocks with five replications. During the dry season there was a decrease in values of stomatal resistance in the following order: guarana > coffee> cashew> guava > rubber, with values from 2.5 to 30.0 s.cm-1. During the rainy season the stomatal resistance values varied from 1.5 to 3.0 s.cm-1. The guarana and coffee crops showed higher resistance to water transpiration when compared to other crops. During the rainy season, the rubber tree continued to present lower stomatal resistance and, consequently, higher transpiration.O experimento foi realizado no Departamento de Produção Vegetal da Escola Superior de Agricultura "Luiz de Queiroz", ESALQ/USP, Piracicaba, São Paulo, Brasil, utilizando-se as culturas de guaranazeiro (Paullinia cupana Kunth, cafeeiro (Coffea arabica L., cajueiro (Anacardium occidentale L., goiabeira (Psidium guajava L. e seringueira (Hevea brasiliensis Muell. - Arg.. No período de seca (setembro/94 e de chuvas (novembro/94, realizaram-se determinações de resistência estomática (RE (s cm-1 e transpiração (T (µg cm-1 s-1 nas diferentes espécies. O delineamento experimental foi em blocos casualizados com cinco repetições. A partir das análises dos dados pode-se concluir: 1. diferenças significativas entre espécies, em termos das variáveis avaliadas no período de deficiência hídrica, com valores decrescentes de resistência estomática e crescente de transpiração na seguinte ordem: guaranazeiro > cafeeiro > cajueiro > goiabeira > seringueira; 2. Nas águas as diferenças entre espécies, para ambas as variáveis, foram menos evidentes, continuando a

  8. Estimation of actual evapotranspiration of Mediterranean perennial crops by means of remote-sensing based surface energy balance models

    Directory of Open Access Journals (Sweden)

    G. Rallo

    2009-07-01

    Full Text Available Actual evapotranspiration from typical Mediterranean crops has been assessed in a Sicilian study area by using surface energy balance (SEB and soil-water balance models. Both modelling approaches use remotely sensed data to estimate evapotranspiration fluxes in a spatially distributed way. The first approach exploits visible (VIS, near-infrared (NIR and thermal (TIR observations to solve the surface energy balance equation whereas the soil-water balance model uses only VIS-NIR data to detect the spatial variability of crop parameters. Considering that the study area is characterized by typical spatially sparse Mediterranean vegetation, i.e. olive, citrus and vineyards, alternating bare soil and canopy, we focused the attention on the main conceptual differences between one-source and two-sources energy balance models. Two different models have been tested: the widely used one-source SEBAL model, where soil and vegetation are considered as the sole source (mostly appropriate in the case of uniform vegetation coverage and the two-sources TSEB model, where soil and vegetation components of the surface energy balance are treated separately. Actual evapotranspiration estimates by means of the two surface energy balance models have been compared vs. the outputs of the agro-hydrological SWAP model, which was applied in a spatially distributed way to simulate one-dimensional water flow in the soil-plant-atmosphere continuum. Remote sensing data in the VIS and NIR spectral ranges have been used to infer spatially distributed vegetation parameters needed to set up the upper boundary condition of SWAP. Actual evapotranspiration values obtained from the application of the soil water balance model SWAP have been considered as the reference to be used for energy balance models accuracy assessment.

    Airborne hyperspectral data acquired during a NERC (Natural Environment Research Council, UK campaign in 2005 have been used. The results of this

  9. Foliar Diseases of Apiaceae Crops in Coastal California

    Science.gov (United States)

    The number of outbreaks of leaf spot, blight and streak diseases on celery, cilantro, fennel and parsley has been increasing throughout central coastal California and particularly in Monterey County since 2002. Two different bacterial pathogens (Pseudomonas syringae pv. apii, and P. syringae pv. cor...

  10. Comparison of Satellite-based Basal and Adjusted Evapotranspiration for Several California Crops

    Science.gov (United States)

    Johnson, L.; Lund, C.; Melton, F. S.

    2013-12-01

    There is a continuing need to develop new sources of information on agricultural crop water consumption in the arid Western U.S. Pursuant to the California Water Conservation Act of 2009, for instance, the stakeholder community has developed a set of quantitative indicators involving measurement of evapotranspiration (ET) or crop consumptive use (Calif. Dept. Water Resources, 2012). Fraction of reference ET (or, crop coefficients) can be estimated from a biophysical description of the crop canopy involving green fractional cover (Fc) and height as per the FAO-56 practice standard of Allen et al. (1998). The current study involved 19 fields in California's San Joaquin Valley and Central Coast during 2011-12, growing a variety of specialty and commodity crops: lettuce, raisin, tomato, almond, melon, winegrape, garlic, peach, orange, cotton, corn and wheat. Most crops were on surface or subsurface drip, though micro-jet, sprinkler and flood were represented as well. Fc was retrospectively estimated every 8-16 days by optical satellite data and interpolated to a daily timestep. Crop height was derived as a capped linear function of Fc using published guideline maxima. These variables were used to generate daily basal crop coefficients (Kcb) per field through most or all of each respective growth cycle by the density coefficient approach of Allen & Pereira (2009). A soil water balance model for both topsoil and root zone, based on FAO-56 and using on-site measurements of applied irrigation and precipitation, was used to develop daily soil evaporation and crop water stress coefficients (Ke, Ks). Key meteorological variables (wind speed, relative humidity) were extracted from the California Irrigation Management Information System (CIMIS) for climate correction. Basal crop ET (ETcb) was then derived from Kcb using CIMIS reference ET. Adjusted crop ET (ETc_adj) was estimated by the dual coefficient approach involving Kcb, Ke, and incorporating Ks. Cumulative ETc

  11. Classical Biological Control of Invasive Legacy Crop Pests: New Technologies Offer Opportunities to Revisit Old Pest Problems in Perennial Tree Crops.

    Science.gov (United States)

    Hoddle, Mark S; Warner, Keith; Steggall, John; Jetter, Karen M

    2014-12-23

    Advances in scientific disciplines that support classical biological control have provided "new tools" that could have important applications for biocontrol programs for some long-established invasive arthropod pests. We suggest that these previously unavailable tools should be used in biological control programs targeting "legacy pests", even if they have been targets of previously unsuccessful biocontrol projects. Examples of "new tools" include molecular analyses to verify species identities and likely geographic area of origin, climate matching and ecological niche modeling, preservation of natural enemy genetic diversity in quarantine, the use of theory from invasion biology to maximize establishment likelihoods for natural enemies, and improved understanding of the interactions between natural enemy and target pest microbiomes. This review suggests that opportunities exist for revisiting old pest problems and funding research programs using "new tools" for developing biological control programs for "legacy pests" could provide permanent suppression of some seemingly intractable pest problems. As a case study, we use citricola scale, Coccus pseudomagnoliarum, an invasive legacy pest of California citrus, to demonstrate the potential of new tools to support a new classical biological control program targeting this insect.

  12. Classical Biological Control of Invasive Legacy Crop Pests: New Technologies Offer Opportunities to Revisit Old Pest Problems in Perennial Tree Crops

    Directory of Open Access Journals (Sweden)

    Mark S. Hoddle

    2014-12-01

    Full Text Available Advances in scientific disciplines that support classical biological control have provided “new tools” that could have important applications for biocontrol programs for some long-established invasive arthropod pests. We suggest that these previously unavailable tools should be used in biological control programs targeting “legacy pests”, even if they have been targets of previously unsuccessful biocontrol projects. Examples of “new tools” include molecular analyses to verify species identities and likely geographic area of origin, climate matching and ecological niche modeling, preservation of natural enemy genetic diversity in quarantine, the use of theory from invasion biology to maximize establishment likelihoods for natural enemies, and improved understanding of the interactions between natural enemy and target pest microbiomes. This review suggests that opportunities exist for revisiting old pest problems and funding research programs using “new tools” for developing biological control programs for “legacy pests” could provide permanent suppression of some seemingly intractable pest problems. As a case study, we use citricola scale, Coccus pseudomagnoliarum, an invasive legacy pest of California citrus, to demonstrate the potential of new tools to support a new classical biological control program targeting this insect.

  13. Perennial Pepperweed Patches - San Francisco Estuary [ds295

    Data.gov (United States)

    California Department of Resources — This layer contains polygon data for the perennial pepperweed (Lepidium latifolium) database. This database represents distribution data collected within the areas...

  14. 78 FR 46249 - Common Crop Insurance Regulations; Arizona-California Citrus Crop Insurance Provisions

    Science.gov (United States)

    2013-07-31

    .... See the Notice related to 7 CFR part 3015, subpart V, published at 48 FR 29115, June 24, 1983... Register at 78 FR 17606-17611. The public was afforded 30 days to submit comments after the regulation was... / Wednesday, July 31, 2013 / Rules and Regulations#0;#0; ] DEPARTMENT OF AGRICULTURE Federal Crop...

  15. Occupational exposure to particulate matter from three agricultural crops in California.

    Science.gov (United States)

    Moran, Rebecca E; Bennett, Deborah H; Garcia, John; Schenker, Marc B

    2014-03-01

    Agricultural work is a major contributor to California's and the nation's economy and employs a large number of workers. However, agricultural work can have numerous risks, such as exposure to elevated levels of particulate matter (PM) and other airborne pollutants with potential adverse health effects. To determine the magnitude of occupational exposures, PM levels were assessed for 89 workers from three major crops in California; almonds, melons and tomatoes. Personal samples were collected for PM2.5 and inhalable PM using personal sampling equipment. Geometric mean concentrations from personal exposure for workers in almonds (inhalable PM=4368 μg/m(3), PM2.5=122 μg/m(3), N=5), tomatoes (inhalable PM=1410 μg/m(3), PM2.5=12 μg/m(3), N=33), and melons (inhalable PM=1118 μg/m(3), PM2.5=19 μg/m(3), N=51) showed high PM exposure when working with these three crops. Large exposure differences by crop were more common than by task (i.e. harvesting, packing and weeding) among the three crops studied. This is the largest study of agricultural workers engaged in hand harvesting, a significant employer of farm labor, and relatively high levels of exposure to PM were measured. PMID:23831254

  16. Simulating greenhouse gas budgets of four California cropping systems under conventional and alternative management.

    Science.gov (United States)

    De Gryze, Steven; Wolf, Adam; Kaffka, Stephen R; Mitchell, Jeff; Rolston, Dennis E; Temple, Steven R; Lee, Juhwan; Six, Johan

    2010-10-01

    Despite the importance of agriculture in California's Central Valley, the potential of alternative management practices to reduce soil greenhouse gas (GHG) emissions has been poorly studied in California. This study aims at (1) calibrating and validating DAYCENT, an ecosystem model, for conventional and alternative cropping systems in California's Central Valley, (2) estimating CO2, N2O, and CH4 soil fluxes from these systems, and (3) quantifying the uncertainty around model predictions induced by variability in the input data. The alternative practices considered were cover cropping, organic practices, and conservation tillage. These practices were compared with conventional agricultural management. The crops considered were beans, corn, cotton, safflower, sunflower, tomato, and wheat. Four field sites, for which at least five years of measured data were available, were used to calibrate and validate the DAYCENT model. The model was able to predict 86-94% of the measured variation in crop yields and 69-87% of the measured variation in soil organic carbon (SOC) contents. A Monte Carlo analysis showed that the predicted variability of SOC contents, crop yields, and N2O fluxes was generally smaller than the measured variability of these parameters, in particular for N2O fluxes. Conservation tillage had the smallest potential to reduce GHG emissions among the alternative practices evaluated, with a significant reduction of the net soil GHG fluxes in two of the three sites of 336 +/- 47 and 550 +/- 123 kg CO2-eq x ha(-1) x yr(-1) (mean +/- SE). Cover cropping had a larger potential, with net soil GHG flux reductions of 752 +/- 10, 1072 +/- 272, and 2201 +/- 82 kg CO2-eq x ha(-1) x yr(-1). Organic practices had the greatest potential for soil GHG flux reduction, with 4577 +/- 272 kg CO2-eq x ha(-1) x yr(-1). Annual differences in weather or management conditions contributed more to the variance in annual GHG emissions than soil variability did. We concluded that the

  17. Effect of harvest timing on leaf production and yield of diterpene glycosides in Stevia rebaudiana Bert: a specialty perennial crop for Mississippi

    Science.gov (United States)

    Stevia rebaundiana (Bertoni), a perennial shrub of the Asteraceae, is one of the most important sources of non-caloric natural sweeteners. Stevia’s plant extracts and glycosides have been used for several years in Paraguay and Brazil. Several studies suggest that Stevia and its glycosides exert ben...

  18. Efficient crop type mapping based on remote sensing in the Central Valley, California

    Science.gov (United States)

    Zhong, Liheng

    Most agricultural systems in California's Central Valley are purposely flexible and intentionally designed to meet the demands of dynamic markets. Agricultural land use is also impacted by climate change and urban development. As a result, crops change annually and semiannually, which makes estimating agricultural water use difficult, especially given the existing method by which agricultural land use is identified and mapped. A minor portion of agricultural land is surveyed annually for land-use type, and every 5 to 8 years the entire valley is completely evaluated. So far no effort has been made to effectively and efficiently identify specific crop types on an annual basis in this area. The potential of satellite imagery to map agricultural land cover and estimate water usage in the Central Valley is explored. Efforts are made to minimize the cost and reduce the time of production during the mapping process. The land use change analysis shows that a remote sensing based mapping method is the only means to map the frequent change of major crop types. The traditional maximum likelihood classification approach is first utilized to map crop types to test the classification capacity of existing algorithms. High accuracy is achieved with sufficient ground truth data for training, and crop maps of moderate quality can be timely produced to facilitate a near-real-time water use estimate. However, the large set of ground truth data required by this method results in high costs in data collection. It is difficult to reduce the cost because a trained classification algorithm is not transferable between different years or different regions. A phenology based classification (PBC) approach is developed which extracts phenological metrics from annual vegetation index profiles and identifies crop types based on these metrics using decision trees. According to the comparison with traditional maximum likelihood classification, this phenology-based approach shows great advantages

  19. What makes a perennial a perennial? A meta-analysis of allocation patterns and functional traits in congeneric annual and perennial plant

    Science.gov (United States)

    Vico, Giulia; Manzoni, Stefano; Weih, Martin

    2014-05-01

    Currently, a large fraction of food, fiber, and feed is provided by annual crops - in particular annual grains. A shift from annual to perennial crops has been advocated to move towards a more sustainable agriculture. While providing lower yields than annuals, perennial crops are often assumed to reduce soil erosion, promote soil health, and be able to achieve higher water and nitrogen use efficiency, primarily through higher allocation below ground. Nevertheless, quantifications of these benefits are still scarce and often inconclusive, as well as mostly limited to first-year perennials. Here we consider congeneric annual and perennial species pairs, for which measured productivity, resource allocation, and resource use efficiency are available in the literature, in search for a signature of life-history (i.e., annuality vs. perenniality) on plant allocation, traits, and agronomic performances. A new database of allocation strategies and functional traits of these congeneric species is developed, covering more than 25 genera of agronomical and ecological relevance, including wild and domesticated species, as well as new hybrids, grown under a variety of conditions. Some general patterns emerge. Perennials have lower biomass allocation to reproductive structures (as expected), and generally higher root-to-shoot biomass ratio, potentially promoting soil C accumulation. Patterns in nitrogen tissue concentration and resource use efficiencies are less clear, due to the limited available data. Our analyses highlight a paucity of comprehensive studies, hampering our understanding of the long-term implications of a shift to perennial crops for ecosystem hydrologic and biogeochemical cycles.

  20. Agricultural damages and losses from ARkStorm scenario flooding in California

    Science.gov (United States)

    Wein, Anne; David Mitchell,; Peters, Jeff; John Rowden,; Johnny Tran,; Alessandra Corsi,; Dinitz, Laura B.

    2016-01-01

    Scientists designed the ARkStorm scenario to challenge the preparedness of California communities for widespread flooding with a historical precedence and increased likelihood under climate change. California is an important provider of vegetables, fruits, nuts, and other agricultural products to the nation. This study analyzes the agricultural damages and losses pertaining to annual crops, perennial crops, and livestock in California exposed to ARkStorm flooding. Statewide, flood damage is incurred on approximately 23% of annual crop acreage, 5% of perennial crop acreage, and 5% of livestock, e.g., dairy, feedlot, and poultry, acreage. The sum of field repair costs, forgone income, and product replacement costs span $3.7 and $7.1 billion (2009) for a range of inundation durations. Perennial crop loss estimates dominate, and the vulnerability of orchards and vineyards has likely increased with recent expansion. Crop reestablishment delays from levee repair and dewatering more than double annual crop losses in the delta islands, assuming the fragile system does not remain permanently flooded. The exposure of almost 200,000 dairy cows to ARkStorm flooding poses livestock evacuation challenges. Read More: http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29NH.1527-6996.0000174

  1. Genomics and the Contrasting Dynamics of Annual and Perennial Domestication.

    Science.gov (United States)

    Gaut, Brandon S; Díez, Concepción M; Morrell, Peter L

    2015-12-01

    Plant domestication modifies a wild species genetically for human use. Among thousands of domesticated plants, a major distinction is the difference between annual and perennial life cycles. The domestication of perennials is expected to follow different processes than annuals, with distinct genetic outcomes. Here we examine domestication from a population genetics perspective, with a focus on three issues: genetic bottlenecks during domestication, introgression as a source of local adaptation, and genetic load. These three issues have been studied nominally in major annual crops but even less extensively in perennials. Here we highlight lessons from annual plants, motivations to study these issues in perennial plants, and new approaches that may lead to further progress.

  2. Perennial aneuploidy as a potential material for gene introgression between maize and Zea perennis

    Institute of Scientific and Technical Information of China (English)

    FU Jie; TANG Qi-lin; YANG Xiu-yan; CHENG Ming-jun; LÜ Gui-hua; WANG Pei; WU Yuan-qi; ZHENG Ming-min; ZHOU Shu-feng; RONG Ting-zhao

    2015-01-01

    Hybridization, which al ows for gene lfow between crops, is dififcult between maize and Zea perennis. In this study, we aim to initiate and study gene lfow between maize and Z. perennis via a special aneuploid plant (MDT) derived from an interspeciifc hybrid of the two species. The chromosome constitution and morphological characters of MDT as wel as certain backcross progenies were examined. Results from genomic in situ hybridization (GISH) indicate that aneuploid MDT consisted of nine maize chromosomes and 30 Z. perennis chromosomes. The backcross progenies of MDT×maize displayed signiifcant diversity of vegetative and ear morphology;several unusual plants with speciifc chromosome constitution were founded in its progenies. Some special perennial progeny with several maize chromosomes were obtained by backcrossing MDT with Z. perennis, and the ifrst whole chromosome introgression from maize to Z. perennis was detected in this study. With this novel material and method, a number of maize-tetraploid teosinte addition or substitution lines can be generated for further study, which has great signiifcance to maize and Z. perennis genetic research, especial y for promoting introgression and transferring desirable traits.

  3. Crop Loss Relationships and Economic Injury Levels for Ferrisia gilli (Hemiptera: Pseudococcidae) Infesting Pistachio in California.

    Science.gov (United States)

    Haviland, David R; Beede, Robert H; Daane, Kent M

    2015-12-01

    Ferrisia gilli Gullan (Hemiptera: Pseudococcidae) is a new pest in California pistachios, Pistacea vera L. We conducted a 3-yr field study to determine the type and amount of damage caused by F. gilli. Using pesticides, we established gradients of F. gilli densities in a commercial pistachio orchard near Tipton, CA, from 2005 to 2007. Each year, mealybug densities on pistachio clusters were recorded from May through September and cumulative mealybug-days were determined. At harvest time, nut yield per tree (5% dried weight) was determined, and subsamples of nuts were evaluated for market quality. Linear regression analysis of cumulative mealybug-days against fruit yield and nut quality measurements showed no relationships in 2005 and 2006, when mealybug densities were moderate. However, in 2007, when mealybug densities were very high, there was a negative correlation with yield (for every 1,000 mealybug-days, there was a decrease in total dry weight per tree of 0.105 kg) and percentage of split unstained nuts (for every 1,000 mealybug-days, there was a decrease in the percentage of split unstained of 0.560%), and a positive correlation between the percentage of closed kernel and closed blank nuts (for every 1,000 mealybug-days, there is an increase in the percentage of closed kernel and closed blank of 0.176 and 0.283%, respectively). The data were used to determine economic injury levels, showing that for each mealybug per cluster in May there was a 4.73% reduction in crop value associated with quality and a 0.866 kg reduction in yield per tree (4.75%).

  4. Perennial roots to immortality.

    Science.gov (United States)

    Munné-Bosch, Sergi

    2014-10-01

    Maximum lifespan greatly varies among species, and it is not strictly determined; it can change with species evolution. Clonal growth is a major factor governing maximum lifespan. In the plant kingdom, the maximum lifespans described for clonal and nonclonal plants vary by an order of magnitude, with 43,600 and 5,062 years for Lomatia tasmanica and Pinus longaeva, respectively. Nonclonal perennial plants (those plants exclusively using sexual reproduction) also present a huge diversity in maximum lifespans (from a few to thousands of years) and even more interestingly, contrasting differences in aging patterns. Some plants show a clear physiological deterioration with aging, whereas others do not. Indeed, some plants can even improve their physiological performance as they age (a phenomenon called negative senescence). This diversity in aging patterns responds to species-specific life history traits and mechanisms evolved by each species to adapt to its habitat. Particularities of roots in perennial plants, such as meristem indeterminacy, modular growth, stress resistance, and patterns of senescence, are crucial in establishing perenniality and understanding adaptation of perennial plants to their habitats. Here, the key role of roots for perennial plant longevity will be discussed, taking into account current knowledge and highlighting additional aspects that still require investigation. PMID:24563283

  5. Leguminosas herbáceas perenes para utilização como coberturas permanentes de solo na Caatinga Mineira Perennial herbaceous legumes used as permanent cover cropping in the Caatinga Mineira

    Directory of Open Access Journals (Sweden)

    Ricardo Borges Teodoro

    2011-06-01

    Full Text Available O presente trabalho objetivou avaliar o comportamento e as potencialidades de leguminosas herbáceas perenes para o uso como cobertura permanente em solos da região da Caatinga Mineira, Médio Vale do Jequitinhonha, MG, visando a introdução dessas plantas de cobertura em áreas agrícolas. O experimento foi conduzido de dezembro de 2008 a julho de 2009. O delineamento experimental foi em blocos ao acaso, com seis tratamentos e quatro repetições. Os tratamentos foram constituídos pelas leguminosas: cudzu tropical (Pueraria phaseoloides, calopogônio (Calopogonium mucunoides, amendoim forrageiro (Arachis pintoi, soja perene (Glycine wightii, estilosantes (Stylosanthes capitata, Stylosanthes macrocephala e pela testemunha (sem a presença de leguminosa. Foram avaliados os seguintes parâmetros: emergência das plântulas; taxa de cobertura do solo; promoção da retenção de umidade e temperatura do solo; capacidade de inibição da vegetação espontânea; potencial de deposição de folhas e de aporte de macronutrientes pela senescência de folhas; produção total de fitomassa seca e acúmulo de macronutrientes na parte aérea. A cobertura plena do solo foi alcançada pelo calopogônio, amendoim forrageiro e cudzu tropical. O calopogônio conferiu maior capacidade de retenção da umidade e inibição das plantas espontâneas. Em todos os tratamentos com leguminosas a temperatura do solo foi inferior à testemunha, a partir dos 120 dias de ciclo. Na região da Caatinga Mineira, as leguminosas perenes calopogônio e cudzu tropical, podem contribuir significativamente para o incremento de nitrogênio, aporte de outros macronutrientes (K, P, Ca e Mg e incremento da matéria orgânica do solo.The study objective was to evaluate the performance and potential of perennial herbaceous legumes for use as permanent soil cover in the Caatinga Mineira region MG, Brazil, for the introduction of these cover crops in agricultural areas. The experimental

  6. Trade-offs between seed output and life span - a quantitative comparison of traits between annual and perennial congeneric species.

    Science.gov (United States)

    Vico, Giulia; Manzoni, Stefano; Nkurunziza, Libère; Murphy, Kevin; Weih, Martin

    2016-01-01

    Perennial plants allocate more resources belowground, thus sustaining important ecosystem services. Hence, shifting from annual to perennial crops has been advocated towards a more sustainable agriculture. Nevertheless, wild perennial species have lower seed production than selected annuals, raising the questions of whether there is a fundamental trade-off between reproductive effort and life span, and whether such trade-off can be overcome through selection. In order to address these questions and to isolate life span from phylogenetic and environmental factors, we conducted a meta-analysis encompassing c. 3000 congeneric annual/perennial pairs from 28 genera. This meta-analysis is complemented with a minimalist model of long-term productivity in perennial species. Perennials allocate more resources belowground and less to seeds than congeneric annuals, independently of selection history. However, existing perennial wheat and rice could achieve yields similar to annuals if they survived three years and each year doubled their biomass, as other perennial grasses do. Selected perennial crops maintain the large belowground allocation of wild perennials, and thus can provide desired regulatory ecosystem services. To match the seed yield of annuals, biomass production of perennial grains must be increased to amounts attained by some perennial grasses - if this goal can be met, perennial crops can provide a more sustainable alternative to annuals. PMID:26214792

  7. Valuing Catastrophic Losses for Perennial Agricultural Crops

    OpenAIRE

    Adams, Damian C.; Kilmer, Richard L.; Moss, Charles B.; Schmitz, Andrew

    2003-01-01

    Courts are often required to estimate changes in welfare to agricultural operations from catastrophic events. For example, courts must assign damages in lawsuits, such as with pesticide drift cases, or determine 'just compensation' when the government takes private land for public use, as with the removal of dairy farms from environmentally sensitive land or destruction of canker-contaminated citrus trees. In economics, the traditional method of estimating changes in producer welfare is the c...

  8. 7 CFR 457.121 - Arizona-California citrus crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... type, if applicable: (1) The number of trees damaged, dehorned or removed; any change in practices or... fresh packed citrus fruit crop as shown below. In the absence of marketing records on a carton basis, production will be converted to cartons on the basis of the following average net pounds of packed fruit in...

  9. Brachypodium sylvaticum, a model for perennial grasses: transformation and inbred line development.

    Directory of Open Access Journals (Sweden)

    Michael A Steinwand

    Full Text Available Perennial species offer significant advantages as crops including reduced soil erosion, lower energy inputs after the first year, deeper root systems that access more soil moisture, and decreased fertilizer inputs due to the remobilization of nutrients at the end of the growing season. These advantages are particularly relevant for emerging biomass crops and it is projected that perennial grasses will be among the most important dedicated biomass crops. The advantages offered by perennial crops could also prove favorable for incorporation into annual grain crops like wheat, rice, sorghum and barley, especially under the dryer and more variable climate conditions projected for many grain-producing regions. Thus, it would be useful to have a perennial model system to test biotechnological approaches to crop improvement and for fundamental research. The perennial grass Brachypodiumsylvaticum is a candidate for such a model because it is diploid, has a small genome, is self-fertile, has a modest stature, and short generation time. Its close relationship to the annual model Brachypodiumdistachyon will facilitate comparative studies and allow researchers to leverage the resources developed for B. distachyon. Here we report on the development of two keystone resources that are essential for a model plant: high-efficiency transformation and inbred lines. Using Agrobacterium tumefaciens-mediated transformation we achieved an average transformation efficiency of 67%. We also surveyed the genetic diversity of 19 accessions from the National Plant Germplasm System using SSR markers and created 15 inbred lines.

  10. Brachypodium sylvaticum, a model for perennial grasses: transformation and inbred line development.

    Science.gov (United States)

    Steinwand, Michael A; Young, Hugh A; Bragg, Jennifer N; Tobias, Christian M; Vogel, John P

    2013-01-01

    Perennial species offer significant advantages as crops including reduced soil erosion, lower energy inputs after the first year, deeper root systems that access more soil moisture, and decreased fertilizer inputs due to the remobilization of nutrients at the end of the growing season. These advantages are particularly relevant for emerging biomass crops and it is projected that perennial grasses will be among the most important dedicated biomass crops. The advantages offered by perennial crops could also prove favorable for incorporation into annual grain crops like wheat, rice, sorghum and barley, especially under the dryer and more variable climate conditions projected for many grain-producing regions. Thus, it would be useful to have a perennial model system to test biotechnological approaches to crop improvement and for fundamental research. The perennial grass Brachypodiumsylvaticum is a candidate for such a model because it is diploid, has a small genome, is self-fertile, has a modest stature, and short generation time. Its close relationship to the annual model Brachypodiumdistachyon will facilitate comparative studies and allow researchers to leverage the resources developed for B. distachyon. Here we report on the development of two keystone resources that are essential for a model plant: high-efficiency transformation and inbred lines. Using Agrobacterium tumefaciens-mediated transformation we achieved an average transformation efficiency of 67%. We also surveyed the genetic diversity of 19 accessions from the National Plant Germplasm System using SSR markers and created 15 inbred lines. PMID:24073248

  11. Estimated Perennial Streams in Idaho

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Perennial streams in Idaho have been modeled using regression equations for 7-day, 2-year low flows (7Q2) described in Wood and others (2009, U.S. Geological Survey...

  12. Energy-conserving perennial agriculture for marginal land in southern Appalachia. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Williams, G.

    1982-01-30

    USDA economists predict the end of surplus farm production in the US within this decade. More and more marginal land will be cropped to provide feed for the growing world population and to produce energy. Much of this potential cropland in Southern Appalachia is poorly suited to annual crops, such as corn. Perennial crops are much better suited to steep, rocky, and wet sites. Research was undertaken on the theoretical potentials of perennial species with high predicted yields of protein, carbohydrates, or oils. Several candidate staple perennial crops for marginal land in Southern Appalachia were identified, and estimates were made of their yields, energy input requirements, and general suitabilities. Cropping systems incorporating honeylocust, persimmon, mulberry, jujube, and beech were compared with corn cropping systems. It appears that these candidate staple perennials show distinct advantages for energy conservation and environmental preservation. Detailed economic analyses must await actual demonstration trials, but preliminary indications for ethanol conversion systems with honeylocust are encouraging. It is suggested that short-term loans to farmers undertaking this new type of agriculture would be appropriate to solve cash-flow problems.

  13. Cumulative drought and land-use impacts on perennial vegetation across a North American dryland region

    Science.gov (United States)

    Munson, Seth M.; Long, A. Lexine; Wallace, Cynthia; Webb, Robert H.

    2016-01-01

    Question The decline and loss of perennial vegetation in dryland ecosystems due to global change pressures can alter ecosystem properties and initiate land degradation processes. We tracked changes of perennial vegetation using remote sensing to address the question of how prolonged drought and land-use intensification have affected perennial vegetation cover across a desert region in the early 21st century? Location Mojave Desert, southeastern California, southern Nevada, southwestern Utah and northwestern Arizona, USA. Methods We coupled the Moderate-Resolution Imaging Spectroradiometer Enhanced Vegetation Index (MODIS-EVI) with ground-based measurements of perennial vegetation cover taken in about 2000 and about 2010. Using the difference between these years, we determined perennial vegetation changes in the early 21st century and related these shifts to climate, soil and landscape properties, and patterns of land use. Results We found a good fit between MODIS-EVI and perennial vegetation cover (2000: R2 = 0.83 and 2010: R2 = 0.74). The southwestern, far southeastern and central Mojave Desert had large declines in perennial vegetation cover in the early 21st century, while the northeastern and southeastern portions of the desert had increases. These changes were explained by 10-yr precipitation anomalies, particularly in the cool season and during extreme dry or wet years. Areas heavily impacted by visitor use or wildfire lost perennial vegetation cover, and vegetation in protected areas increased to a greater degree than in unprotected areas. Conclusions We find that we can extrapolate previously documented declines of perennial plant cover to an entire desert, and demonstrate that prolonged water shortages coupled with land-use intensification create identifiable patterns of vegetation change in dryland regions.

  14. Biomassa microbiana e atividade enzimática em solos sob vegetação nativa e sistemas agrícolas anuais e perenes na região de Primavera do Leste (MT Microbial biomass and enzyme activities in soils under native vegetation and under annual and perennial cropping systems at the Primavera do Leste region - Mato Grosso State

    Directory of Open Access Journals (Sweden)

    M. Matsuoka

    2003-06-01

    microbial biomass and enzyme activities in soils under native vegetation (known as "Cerradão" and in soils under annual and perennial cropping systems. Soil samples were collected, at the beginning of the rainy season, at two depths (0-5 and 5-20 cm in areas under a vineyard (row and between rows, annual crops (soybean and native vegetation. The parameters evaluated were soil microbial biomass carbon (MBC, readily mineralizable carbon (microbial respiration and the soil enzymes beta-glucosidase, acid phosphatase and arylsulfatase. In relation to the native area, at the two depths reductions of up to 70% in the MBC were observed in the annual and perennial cropping systems. The soil management conducted in the area between the rows of the vineyard along with the presence of the grass Eleusine indica, as a cover crop, favored an increase in the levels of readily mineralizable carbon, and the beta-glucosidase and arilsulfatase activities. The P content of the soil under Cerradão, at the two depths, reduced the levels of acid phosphatase activities as compared to other places of the Cerrados region. Nevertheless, at the 0-5 cm depth the phosphatase activity of the Cerradão area was greater than in the annual crops, showing the importance of this enzyme on organic P cycling in native ecosystems. The results confirmed the sensibility of microbiological and biochemical parameters to evaluate changes that occurred in soil as a consequence of different management systems.

  15. The effect of perennials as green manure on cereal productivity and disease incidence

    Energy Technology Data Exchange (ETDEWEB)

    Skuodiene, R.; Nekrosiene, R.

    2012-11-01

    Field experiments were conducted at the Vezaiciai Branch of the Lithuanian Research Centre for Agriculture and Forestry during the period 2002-2007. They were designed to ascertain the effects of phytomass of different perennial pre-crops used for green manure on the productivity and on the occurrence of foliar fungal diseases of cereal agrocenoses. Plant residues and phytomass ploughed down as green manures positively affected cereal indices of crop productivity not only for the first but for the second year as well. It influenced the productivity of cereal segments. The largest amount of metabolizable energy was in the yield of cereal sequence under white clover (Trifolium repens L.) 83.23-84.76% GJ ha{sup 1}. The potential accumulated by perennials of the second year of development was more efficiently utilised by winter triticale (Triticosecale Wittm.) cv. Tevo, and that of perennials of the third year of development was more efficiently utilised by spring barley (Hordeum vulgare L.) cv. Ula. Perennials had a significant effect on the spread of foliar diseases in winter triticale (Triticosecale Wittm.) and spring barley (Hordeum vulgare L.) agrocenoses. The severity of the disease was 1.1-1.3 times higher in the winter triticale (Triticosecale Wittm.) treatments with white clover (Trifolium repens L.) pre-crops. Foliar disease incidence and severity was 1.1-1.2 times higher in the agrocenoses of spring barley (Hordeum vulgare L.) after legumes of the third year of development, especially after lucerne (Medicago sativa L.). (Author) 28 refs.

  16. Scaling water use of perennial grasses from the plot to Midwestern U.S.

    Science.gov (United States)

    Bernacchi, C. J.; VanLoocke, A. D.; Hickman, G. C.; Zeri, M.; Twine, T. E.

    2011-12-01

    Perennial rhizomatous C4 grasses are currently considered, in many regions, one of the most promising vegetation types to supply biomass for bioenergy production. Because one goal of bioenergy production is to benefit the environment, the potential environmental impacts and services that would be associated with large scale production must be investigated. Of particular interest is the impact that altering the composition of vegetation at the landscape scale would have on regional hydrological cycles driven by higher rates of evapotranspiration (ET). To assess this, we implemented micrometeorological measurements using two independent techniques over multiple growing seasons for replicated plots of two perennial rhizomatous grasses, Miscanthus giganteus (miscanthus) and Panicum virgatum (switchgrass), and two traditional crop species, Zea mays (maize) and Glycine Max (soybean), planted throughout Central Illinois. When averaged across the entire growing season, ET for miscanthus was double relative to annual crops, and 140% of P. virgatum ET. The differences between the perennial grasses and annual crops were primarily due to longer growing season associated with the perennial grasses, but Miscanthus also demonstrated higher instantaneous water use. These results, coupled with physiological measurements of these species, were then used to parameterize and validate a dynamic vegetation model, Agro-IBIS, to investigate the large-scale consequences of land-use change on ecosystem hydrology from existing agriculture to various perennial grass production scenarios ranging from 10% to 100%. Results show that uniform production scenarios of less than 25% have little impact on regional hydrology but 'hotspots' with higher percentage land cover devoted to perennial grasses can have important consequences in localized areas. Given the increasing demand on water, we investigated whether the increased carbon gain associated with bioenergy crops was sufficient to offset the

  17. Genetic variation, population structure, and linkage disequilibrium in European elite germplasm of perennial ryegrass

    DEFF Research Database (Denmark)

    Brazauskas, Gintaras; Lenk, Ingo; Pedersen, Morten Greve;

    2011-01-01

    Perennial ryegrass (Lolium perenne L.) is a highly valued temperate climate grass species grown as forage crop and for amenity uses. Due to its outbreeding nature and recent domestication, a high degree of genetic diversity is expected among cultivars. The aim of this study was to assess the extent...... and occurred within 0.4 cM across European varieties, when population structure was taken into consideration. However, an extended LD of up to 6.6 cM was detected within the variety Aberdart. High genetic diversity and rapid LD decay provide means for high resolution association mapping in elite materials...... of linkage disequilibrium (LD) within European elite germplasm and to evaluate the appropriate methodology for genetic association mapping in perennial ryegrass. A high level of genetic diversity was observed in a set of 380 perennial ryegrass elite genotypes when genotyped with 40 SSRs and 2 STS markers...

  18. The impact of new energy crops on weed flora diversification in energy cropping systems

    Directory of Open Access Journals (Sweden)

    Glemnitz, Michael

    2016-02-01

    Full Text Available Despite various options in energy cropping for the diversification of agricultural land use, such as the introduction of new crops, in practice, there is a one-sided orientation toward the use of maize as biogas feedstock in Germany. One reason, why they are not yet introduced in practice, is that for most of them neither the agricultural feasibility nor their ecological and economic benefit could be clearly shown to the farmers up to now. As part of the research projects “Site-adapted Cropping Systems for Energy Crops” (EVA, and “Optimized energy cropping systems for the sustainable biogas production (Upscaling” the effects of three new energy crops have been tested under real farm conditions in two different regions in the northern part of Germany. The large scale field trial consisted of the comparison of the following energy crops: 0- maize as reference crop, 1- perennial Silphie (Silphium perfoliatum, 2- Szarvasi grass (Agropyron elongatum, and 3-perennial wild flower mixture. The trail has been investigated regarding the following effects: α-diversity at the plot scale, contribution to the β-diversity among the crops and species composition. The results suggest that the integration of the new perennial energy crop might contribute to an essential weed diversity enhancement. Weed flora diversity was between 2-4 times higher in most of the cases in the new energy crops compared to maize.

  19. Perennial grasslands enhance biodiversity and multiple ecosystem services in bioenergy landscapes.

    Science.gov (United States)

    Werling, Ben P; Dickson, Timothy L; Isaacs, Rufus; Gaines, Hannah; Gratton, Claudio; Gross, Katherine L; Liere, Heidi; Malmstrom, Carolyn M; Meehan, Timothy D; Ruan, Leilei; Robertson, Bruce A; Robertson, G Philip; Schmidt, Thomas M; Schrotenboer, Abbie C; Teal, Tracy K; Wilson, Julianna K; Landis, Douglas A

    2014-01-28

    Agriculture is being challenged to provide food, and increasingly fuel, for an expanding global population. Producing bioenergy crops on marginal lands--farmland suboptimal for food crops--could help meet energy goals while minimizing competition with food production. However, the ecological costs and benefits of growing bioenergy feedstocks--primarily annual grain crops--on marginal lands have been questioned. Here we show that perennial bioenergy crops provide an alternative to annual grains that increases biodiversity of multiple taxa and sustain a variety of ecosystem functions, promoting the creation of multifunctional agricultural landscapes. We found that switchgrass and prairie plantings harbored significantly greater plant, methanotrophic bacteria, arthropod, and bird diversity than maize. Although biomass production was greater in maize, all other ecosystem services, including methane consumption, pest suppression, pollination, and conservation of grassland birds, were higher in perennial grasslands. Moreover, we found that the linkage between biodiversity and ecosystem services is dependent not only on the choice of bioenergy crop but also on its location relative to other habitats, with local landscape context as important as crop choice in determining provision of some services. Our study suggests that bioenergy policy that supports coordinated land use can diversify agricultural landscapes and sustain multiple critical ecosystem services.

  20. Productivity and carbon footprint of perennial grass-forage legume intercropping strategies with high or low nitrogen fertilizer input

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, Henrik; Lachouani, Petra; Knudsen, Marie Trydeman;

    2016-01-01

    A three-season field experiment was established and repeated twice with spring barley used as cover crop for different perennial grass-legume intercrops followed by a full year pasture cropping and winter wheat after sward incorporation. Two fertilization regimes were applied with plots fertilized...... in the high fertilizer treatment. Nitrous oxide emissions were highest in the treatments containing legumes. The LCA showed that the low input N systems had markedly lower carbon footprint values than crops from the high N input system with the pure stand legumes without N fertilization having the lowest...... reducing crop yields and thereby farmers earnings....

  1. Selectivity of some herbicides to perennial ryegrass (Lolium perenne L.), grown for seed production

    OpenAIRE

    Tsvetanka Dimitrova; Aneliya Katova

    2011-01-01

    During the period 2008-2010, on the experimental field of the Institute of Forage Crops - Pleven, on slightly leached chernozem a study was conducted with the purpose to determine the selectivity of some herbicides to perennial ryegrass (Lolium perenne L.), and their influence on the seed productivity. As a result of the study the following was found: herbicides for broadleaf weeds control - Arat (500 g/l dicamba + 250 g/l tritosulfuron) at rate of 100 ml/h...

  2. Gupta Nitrogen cycling in summer active perennial grass systems in South Australia: Non-symbiotic nitrogen fixation

    NARCIS (Netherlands)

    Gupta, V.V.S.R.; Kroker, S.J.; Hicks, M.; Davoren, W.; Descheemaeker, K.K.E.; Llewellyn, R.

    2014-01-01

    Non-symbiotic nitrogen (N2) fixation by diazotrophic bacteria is a potential source for biological N inputs in non-leguminous crops and pastures. Perennial grasses generally add larger quantities of above- and belowground plant residues to soil, and so can support higher levels of soil biological ac

  3. Landscape control of nitrous oxide emissions during the transition from conservation reserve program to perennial grasses for bioenergy

    Science.gov (United States)

    Future liquid fuel demand from renewable sources may, in part, be met by converting the seasonally wet portions of the landscape currently managed for soil and water conservation to perennial energy crops. However, this shift may increase nitrous oxide (N2O) emissions, thus limiting the carbon benef...

  4. Spread dynamics of perennial pepperweed (Lepidium latifolium) in two seasonal wetland areas

    Science.gov (United States)

    Renz, Mark J.; Steinmaus, Scott J.; Gilmer, David S.; DiTomaso, Joseph M.

    2012-01-01

    Perennial pepperweed is an invasive plant that is expanding rapidly in several plant communities in the western United States. In California, perennial pepperweed has aggressively invaded seasonal wetlands, resulting in degradation of habitat quality. We evaluated the rate and dynamics of population spread, assessed the effect of disturbance on spread, and determined the biotic and abiotic factors influencing the likelihood of invasion. The study was conducted at eight sites within two wetland regions of California. Results indicate that in undisturbed sites, spread was almost exclusively through vegetative expansion, and the average rate of spread was 0.85 m yr−1 from the leading edge. Spread in sites that were disked was more than three times greater than in undisturbed sites. While smaller infestations increased at a faster rate compared with larger populations, larger infestations accumulated more newly infested areas than smaller infestations from year to year. Stem density was consistently higher in the center of the infestations, with about 2.4 times more stems per square meter compared with the leading edge at the perimeter of the population. The invasion by perennial pepperweed was positively correlated with increased water availability but was negatively correlated with the cover of perennial and annual species. Thus, high cover of resident vegetation can have a suppressive effect on the rate of invasion, even in wetland ecosystems. On the basis of these results, we recommend that resident plant cover not be disturbed, especially in wet areas adjacent to areas currently infested with perennial pepperweed. For infested areas, management efforts should be prioritized to focus on controlling satellite populations as well as the leading edge of larger infestations first. This strategy could reduce the need for costly active restoration efforts by maximizing the probability of successful re-establishment of resident vegetation from the adjacent seedbank.

  5. Establishment techniques in under-sown perennial ryegrass for seed production

    DEFF Research Database (Denmark)

    Deleuran, Lise C; Boelt, Birte

    2009-01-01

    Establishment methods have proven to be of major importance for grass-seed production. The objective of this research was to test the effect of different sowing techniques on plant establishment and the subsequent seed yield. Perennial ryegrass (Lolium perenne L.) is used as the model grass due to...... ryegrass when placing the grass 2, 6, or 12 cm from the cover-crop row. Placement of the ryegrass seed crop 6 cm from the cereal row showed that a significant yield increase of 34-71 kg ha-1 can be obtained compared with sowing in the cereal row....

  6. Comparative attributional life cycle assessment of annual and perennial lignocellulosic feedstocks production under Mediterranean climate for biorefinery framework.

    Science.gov (United States)

    Zucaro, Amalia; Forte, Annachiara; Fagnano, Massimo; Bastianoni, Simone; Basosi, Riccardo; Fierro, Angelo

    2015-07-01

    Annual fiber sorghum (FS) and perennial giant reed (GR) cultivated in the Mediterranean area are interesting due to their high productivity under drought conditions and their potential use as lignocellulosic feedstock for biorefinery purposes. This study compares environmental constraints related to FS and GR produced on experimental farms (in the Campania region) using an attributional life cycle assessment (LCA) approach through appropriate modeling of the perennial cultivation. For both crops, primary data were available for agricultural management. Direct field emissions (DFEs) were computed, including the potential soil carbon storage (SCS). Giant reed showed the lowest burdens for all impact categories analyzed (most were in the range of 40%-80% of FS values). More apparent were the differences for climate change and freshwater eutrophication (respectively 80% and 81% lower for GR compared to FS). These results are due to the short-term SCS, experimentally detected in the perennial GR crop (about 0.25 ton C ha(-1) yr(-1), with a global warming offsetting potential of about 0.03 ton CO2/ton(GR dry biomass)). The results are also due to the annual application of triple superphosphate at the sowing fertilization phase for FS, which occurs differently than it does for GR. Phosphorous fertilization was performed only when crops were being established and therefore properly spread along the overall crop lifetime. For both crops, after normalization, terrestrial acidification and particulate matter formation were relevant impact categories, as a consequence of the NH3 DFE by volatilization after urea were spread superficially. Therefore, the results suggest higher environmental benefits of the perennial crop than the annual crop. PMID:25377476

  7. Higher US crop prices trigger little area expansion so marginal land for biofuel crops is limited

    International Nuclear Information System (INIS)

    By expanding energy biomass production on marginal lands that are not currently used for crops, food prices increase and indirect climate change effects can be mitigated. Studies of the availability of marginal lands for dedicated bioenergy crops have focused on biophysical land traits, ignoring the human role in decisions to convert marginal land to bioenergy crops. Recent history offers insights about farmer willingness to put non-crop land into crop production. The 2006-09 leap in field crop prices and the attendant 64% gain in typical profitability led to only a 2% increase in crop planted area, mostly in the prairie states. At this rate, a doubling of expected profitability from biomass crops would expand cropland supply by only 3.2%. Yet targets for cellulosic ethanol production in the US Energy Independence and Security Act imply boosting US planted area by 10% or more with perennial biomass crops. Given landowner reluctance to expand crop area with familiar crops in the short run, large scale expansion of the area in dedicated bioenergy crops will likely be difficult and costly to achieve. - Highlights: → Biofuel crops on cropland can displace food crops, reducing food supply and triggering indirect land use. → Growing biofuel crops on non-crop marginal land avoids these problems. → But US farmers expanded cropland by only 2% when crop profitability jumped 64% during 2006-09. → So medium-term availability of marginal lands for biofuel crops is limited and costly.

  8. Using corngrass1 to engineer poplar as a bioenergy crop

    Energy Technology Data Exchange (ETDEWEB)

    Meilan, Richard; Rubinelli, Peter Marius; Chuck, George

    2016-05-10

    Embodiments of the present invention relate generally to new bioenergy crops and methods of creating new bioenergy crops. For example, genes encoding microRNAs (miRNAs) are used to create transgenic crops. In some embodiments, over-expression of miRNA is used to produce transgenic perennials, such as trees, with altered lignin content or composition. In some embodiments, the transgenic perennials are Populus spp. In some embodiments, the miRNA is a member of the miR156 family. In some embodiments, the gene is Zea mays Cg1.

  9. Exploring an Annotated Sequence Assembly of the Perennial Ryegrass Genome for Genomic Regions Enriched for Trait Associated Variants

    DEFF Research Database (Denmark)

    Byrne, Stephen; Cericola, Fabio; Janss, Luc;

    2015-01-01

    Perennial ryegrass (Lolium perenne L.) is an outbreeding diploid species and one of the most important forage crops used in temperate agriculture. We have developed a draft sequence assembly of the perennial ryegrass genome and annotated it with the aid of RNA-seq data from various genotypes, plant...... components, and treatments. We predicted 39,795 high quality proteins originating from 28,182 genetic loci. We wanted to use the annotated assembly to study if SNPs falling within various annotation classes explain differing proportions of the variance for traits such as heading date and rust resistance...

  10. Precision overhead irrigation is suitable for several Central Valley crops

    OpenAIRE

    Mitchell, Jeffrey P; Anil Shrestha; Joy Hollingsworth; Daniel Munk; Hembree, Kurt J; Tom A. Turini

    2016-01-01

    Overhead systems are the dominant irrigation technology in many parts of the world, but they are not widely used in California even though they have higher water application efficiency than furrow irrigation systems and lower labor requirements than drip systems. With water and labor perennial concerns in California, the suitability of overhead systems merits consideration. From 2008 through 2013, in studies near Five Points, California, we evaluated overhead irrigation for wheat, corn, cotto...

  11. Estimativa da resistência mecânica à penetração de um latossolo vermelho sob cultura perene no norte do estado do Paraná Estimating penetration resistance of an oxisol under perennial crop in northern Paraná state

    Directory of Open Access Journals (Sweden)

    Adriana Aparecida Ribon

    2008-10-01

    concluir que as equações que melhor estimaram a resistência do solo à penetração foram: para Ug 0,30 kg kg-1: RPE = 3,20 - 13,78Ug + 4,43Ds (R² = 0,97. Em todas as situações estudadas, os coeficientes de variação variaram de altos (situação UG1 a muito altos (situação UG2 e Ug3, caracterizando alta variabilidade espacial da RP; logo, a utilização dos modelos selecionados deve ser feita com cautela, pois ocorre importante dispersão de pontos estimados por meio dos modelos, em relação aos valores medidos.Soil resistance to root penetration is an important physical characteristic for defining soil management techniques. The purpose of this study was to estimate the mechanical soil penetration resistance of an Oxisol under perennial crop, at three gravimetrical moisture contents, based on bulk density, moisture, and soil clay and organic matter content. The soil penetration resistance was evaluated by an impact penetrometer and the impact data in dm-1 were converted into dynamic resistance (MPa. At the moment of the determination of the mechanical soil resistance, samples (30 samples for each layer (0-0.10; 0.1-0.3; 0.3-0.5 m were collected to determine three different gravimetrical moisture contents (Ug (Ug1 0.30 kg kg-1 , clay texture (Arg, organic matter (MO and soil bulk density (Ds. Tests of normal distribution were applied to select the participant variables of the models by the W test. Thereafter, analyses of simple correlation between the variable and STEPWISE multiple regression analyses were performed. To fit the models an analysis was performed with four independent variables, represented by: X1 = Ug, X2 = Ds, X3 = MO, X4 = Arg and the dependent variable (y was represented by the soil penetration resistance (RP. After establishing the final models, the effects of multicollinearity were tested by VIF (Variance Increase Factor, where the VIF values 0.30 kg kg-1 :RPE = 3.20 - 13.78Ug + 4.43Ds (R² = 0.97, R = 0.98. In all studied situations the

  12. Chemistry and microbial functional diversity differences in biofuel crop and grassland soils in multiple geographies

    Science.gov (United States)

    As crop and non-crop lands are increasingly converted to biofuel feedstock production, it is of interest to identify potential impacts of annual and perennial feedstocks on soil ecosystem services. Soil samples were obtained from diverse regionally distributed biofuel cropping si...

  13. Affect of crop residue on colonization and survival of Phoma sclerotioides

    Science.gov (United States)

    Phoma sclerotioides causes brown root rot (BRR) of alfalfa and root rot of other perennial legumes and some winter hardy grasses. It can survive as a saprophyte on crop debris so crop residues that support the fungus may increase inocula levels. Current management of BRR is based on crop rotation wi...

  14. Molecular characterization of cytoplasmic male sterility (CMS) in perennial ryegrass ( Lolium perenne L.)

    DEFF Research Database (Denmark)

    Islam, Md. Shofiqul; Møller, Ian Max; Studer, Bruno;

    2011-01-01

    to increase biomass yield, improve nutritional value and tolerance towards abiotic and biotic stress. Cytoplasmic male sterility (CMS) is an efficient tool to control pollination for hybrid seed production. In order to identify the causative polymorphism of the CMS phenotype, a cytoplasmic male sterile plant...... using 454 next-generation sequencing technology, resulting in approximately 800,000 high quality single reads. Here we report on the sequencing and the assembly of the mitochondrial genome from perennial ryegrass. Moreover, the assembly and annotation of the male-sterile and fertile mitochondrial......Perennial ryegrass (Lolium perenne L.) is a key grassland species in temperate climates. As an out breeding crop, ryegrass is currently being bred as population and synthetic families, thereby not fully exploiting the genetically available heterosis. Thus, hybrid breeding has the potential...

  15. Sustainability and integrated weed management in Australian winter cropping systems: a bioeconomic analysis

    OpenAIRE

    Jones, Randall E.

    2005-01-01

    Economic evaluations of the benefits of integrated weed management often only consider the benefits of management in the crop phase, and ignore the impact of rotational options. In particular, non-crop phases such as annual and perennial pasture phases can have a substantial impact upon weed population dynamics and economic returns. Moreover, extended perennial pasture phases are being promoted to address a range of onfarm sustainability issues such as excessive deep drainage (i.e. salinity),...

  16. Sustainable commercialization of new crops for the agricultural bioeconomy

    OpenAIRE

    Jordan, N.R; Dorn, K.; B. Runck; P. Ewing; Williams, A; Anderson, K A; L. Felice; K. Haralson; J. Goplen; Altendorf, K; Fernandez, A.; W. Phippen; Sedbrook, J.; Marks, M.; Wolf, K.

    2016-01-01

    Abstract Diversification of agroecological systems to enhance agrobiodiversity is likely to be critical to advancing environmental, economic, and social sustainability of agriculture. Temperate-zone agroecological systems that are currently organized for production of summer-annual crops can be diversified by integration of fallow-season and perennial crops. Integration of such crops can improve sustainability of these agroecological systems, with minimal interference with current agricultura...

  17. Nitrate Leaching From Grain Maize After Different Tillage Methods and Long/Short Term Cover Cropping

    DEFF Research Database (Denmark)

    Hansen, Elly Møller

    trial initiated in 1968 on a coarse sandy soil. The previous trial included spring sown crops undersown (with or without) perennial ryegrass (Lolium perenne L.) as cover crop, two N-rates (90 and 120 kg N ha-1) and different tillage methods (shallow tillage and ploughing autumn or spring). With maize......, each previous long-term treatment with soil tillage and cover crop was sub-divided into two, one with perennial ryegrass as cover crop and one without cover crop. The maize was sown in 2009 and 2010 and fertilized with 140 kg N ha-1. The objectives were to determine the effects on leaching of i......) previous history of long-term cover cropping, ii) soil tillage methods, iii) N rates and iv) present short-term use of cover cropping in maize. Preliminary results from 2009 – 2011 suggest that leaching after a history of cover cropping tended to be higher than after no history of cover cropping...

  18. Bird Use of Imperial Valley Crops [ds427

    Data.gov (United States)

    California Department of Resources — Agriculture crops in the Imperial Valley of California provide valuable habitat for many resident and migratory birds and are a very important component of the...

  19. Photoperiodic growth control in perennial trees.

    Science.gov (United States)

    Azeez, Abdul; Sane, Aniruddha P

    2015-01-01

    Plants have to cope with changing seasons and adverse environmental conditions. Being sessile, plants have developed elaborate mechanisms for their survival that allow them to sense and adapt to the environment and reproduce successfully. A major adaptive trait for the survival of trees of temperate and boreal forests is the induction of growth cessation in anticipation of winters. In the last few years enormous progress has been made to elucidate the molecular mechanisms underlying SDs induced growth cessation in model perennial tree hybrid aspen (Populus tremula × P. tremuloides). In this review we discuss the molecular mechanism underlying photoperiodic control of growth cessation and adaptive responses.

  20. Genetic markers for flowering in perennial ryegrass

    DEFF Research Database (Denmark)

    Paina, Cristiana; Byrne, Stephen; Andersen, Jeppe Reitan;

    2011-01-01

    Perennial ryegrass (Lolium perenne L.) is the principal forage grass utilized in Danish agriculture and underpins the beef and dairy sectors. It is characterized as having high digestibility, high nutritional value, and high productivity during vegetative growth. However, at the reproductive growth...... genes will be converted to molecular markers and mapped in an existing mapping population previously characterized for flowering time and vernalization response. References: Amasino, R.M., Michaels S.D. (2010). The Timing of Flowering. Plant Physiology 154: 516–520 Greenup, A., W. Peacock, W.J., Dennis...

  1. DNA-free genome editing methods for targeted crop improvement.

    Science.gov (United States)

    Kanchiswamy, Chidananda Nagamangala

    2016-07-01

    Evolution of the next-generation clustered, regularly interspaced, short palindromic repeat/Cas9 (CRISPR/Cas9) genome editing tools, ribonucleoprotein (RNA)-guided endonuclease (RGEN) RNPs, is paving the way for developing DNA-free genetically edited crop plants. In this review, I discuss the various methods of RGEN RNPs tool delivery into plant cells and their limitations to adopt this technology to numerous crop plants. Furthermore, focus is given on the importance of developing DNA-free genome edited crop plants, including perennial crop plants. The possible regulation on the DNA-free, next-generation genome-edited crop plants is also highlighted. PMID:27100964

  2. Modelling critical NDVI curves in perennial ryegrass

    DEFF Research Database (Denmark)

    Gislum, R; Boelt, B

    2010-01-01

      The use of optical sensors to measure canopy reflectance and calculate crop index as e.g. normalized difference vegetation index (NDVI) is widely used in agricultural crops, but has so far not been implemented in herbage seed production. The present study has the purpose to develop a critical N...

  3. The genome and transcriptome of perennial ryegrass mitochondria

    DEFF Research Database (Denmark)

    Islam, Md. Shofiqul; Studer, Bruno; Byrne, Stephen;

    2013-01-01

    and annotation of the complete mitochondrial genome from perennial ryegrass. Results: Intact mitochondria from perennial ryegrass leaves were isolated and used for mtDNA extraction. The mitochondrial genome was sequenced to a 167-fold coverage using the Roche 454 GS-FLX Titanium platform, and assembled...... of the mitochondrial genome from perennial ryegrass presented here constitutes an important tool for future attempts to compare mitochondrial genomes within and between grass species. Our results also demonstrate that mitochondria of perennial ryegrass contain genes crucial for energy production that are well...

  4. The Danish energy crop research and development project - main conclusions

    International Nuclear Information System (INIS)

    Production of energy crops in Denmark is more or less non-existent in Denmark at the time being. However, the need for biomass on the other side of year 2005 exceeds the existing biomass resources and a substantial amount of energy crops will be necessary in order to fulfil the goals in Energy 21. The targeted share of the use of renewable energy sources by year 2030 is approximately 30%. Energy crops are seen as the most important new resource in order to create a balanced input mix of renewable in the energy system. The energy crops are mainly seen as fuel in small and medium sized CHP plants and in the big power plants. The Danish energy crop project consists of three main parts: a demonstration part, a research and development part, and an overall assessment part. Based on the results from the project the following overall conclusions can be made: Seen from a strictly market and production economic point of view energy crops will not be competitive in a foreseeable future, neither as a production for farmers nor as a fuel at the utility companies; The costs per GJ of energy crops are still higher than a GJ of straw; The cost difference between annual and perennial energy crops are slightly in favour of perennials, however the conditions on the individual farms should govern the choice between annual and perennial energy crops; Energy crops must be seen as part of an overall environmental scheme covering both agriculture and the energy sector; Given the right production scheme energy crops can be grown on environmental sensitive areas and on most ground water protection areas; Adding the potential sustainability benefits like reduced nutrient leakage and reduced CO2 emissions energy crops seem to be a sensible and sustainable solution; Due to different handling, storage and fuel characteristics an all year delivery scheme of energy crops should include a mix of different energy crops to keep overall cost down. (BA)

  5. Identification of flowering genes in strawberry, a perennial SD plant

    Directory of Open Access Journals (Sweden)

    Rantanen Marja

    2009-09-01

    Full Text Available Abstract Background We are studying the regulation of flowering in perennial plants by using diploid wild strawberry (Fragaria vesca L. as a model. Wild strawberry is a facultative short-day plant with an obligatory short-day requirement at temperatures above 15°C. At lower temperatures, however, flowering induction occurs irrespective of photoperiod. In addition to short-day genotypes, everbearing forms of wild strawberry are known. In 'Baron Solemacher' recessive alleles of an unknown repressor, SEASONAL FLOWERING LOCUS (SFL, are responsible for continuous flowering habit. Although flower induction has a central effect on the cropping potential, the molecular control of flowering in strawberries has not been studied and the genetic flowering pathways are still poorly understood. The comparison of everbearing and short-day genotypes of wild strawberry could facilitate our understanding of fundamental molecular mechanisms regulating perennial growth cycle in plants. Results We have searched homologs for 118 Arabidopsis flowering time genes from Fragaria by EST sequencing and bioinformatics analysis and identified 66 gene homologs that by sequence similarity, putatively correspond to genes of all known genetic flowering pathways. The expression analysis of 25 selected genes representing various flowering pathways did not reveal large differences between the everbearing and the short-day genotypes. However, putative floral identity and floral integrator genes AP1 and LFY were co-regulated during early floral development. AP1 mRNA was specifically accumulating in the shoot apices of the everbearing genotype, indicating its usability as a marker for floral initiation. Moreover, we showed that flowering induction in everbearing 'Baron Solemacher' and 'Hawaii-4' was inhibited by short-day and low temperature, in contrast to short-day genotypes. Conclusion We have shown that many central genetic components of the flowering pathways in Arabidopsis can

  6. Combined production of free-range pigs and energy crops – animal behaviour and crop damages

    DEFF Research Database (Denmark)

    Horsted, Klaus; Kongsted, Anne Grete; Jørgensen, Uffe;

    2012-01-01

    Intensive free-range pig production on open grasslands has disadvantages in that it creates nutrient hotspots and little opportunity for pigs to seek shelter from the sun. Combining a perennial energy crop and pig production might benefit the environment and animal welfare because perennial energy...... crops like willow (Salix sp.) and Miscanthus offer the pigs protection from the sun while reducing nutrient leaching from pig excrements due to their deep rooting system. The objectives of this study were to evaluate how season and stocking density of pigs in a free-range system with zones of willow...... production of pigs and energy crops is a feasible strategy to benefit both the environment and animal welfare....

  7. Selectivity of Some Herbicides to Perennial ryegrass (Lolium perenne L., Grown for Seed Production

    Directory of Open Access Journals (Sweden)

    Tsvetanka Dimitrova

    2011-01-01

    Full Text Available During the period 2008-2010, on the experimental field of the Institute of Forage Crops – Pleven, on slightly leached chernozem a study was conducted with the purpose to determine the selectivity of some herbicides to perennial ryegrass (Lolium perenne L., and theirinfluence on the seed productivity. As a result of the study the following was found: herbicides for broadleaf weeds control – Arat (500 g/l dicamba + 250 g/l tritosulfuron at rate of 100 ml/ha, Korida 75 VDG (750 g/kg tribenuron-methyl – 15 g/ha and Cambio SL (320 g/l bentazone + 90 g/l dicamba – 1250 ml/ha had high selectivity to perennial ryegrass, applied at 2-4 leaf stage during establishing year of the stand and until the stage of the beginning of shooting up in seed production year. Herbicide for grass weeds control: Topik 080EK (80 g/l clodinafop-prop-argyl + antidote at rate of 300 ml/ha, applied at the same stage can be applied in seed production stands of perennial ryegrass. Herbicide for grass weeds control – Grasp 25SK (250 g/l tralkoxydim + Atplus 463 at rate of 1000 + 1000 ml/ha showed phytotoxic effect on L. perenne and caused the reduction of seed and dry biomass productivity. Realization of the biological potential concerning seed and dry mass yield of perennial ryegrass demands application of selective herbicides Arat, Korida 75 VDG and Cambio SL in control of broadleaf weeds and Topik 080EK in control of grass weeds.

  8. ECOLOGY AND MANAGEMENT OF PERENNIAL PEPPERWEED [Lepidium latifolium L.

    Science.gov (United States)

    Perennial pepperweed, also called tall whitetop and often confused with whitetop (Cardaria draba), is a rhizomatous perennial weed threatening riparian areas, irrigation ditches, and floodplain meadows in Montana. This weed in the mustard family (Brassicaceae) spreads by creeping roots and rhizomes...

  9. A comparison of canopy evapotranspiration between perennial rhizomatous grasses and Zea mays

    Science.gov (United States)

    Hickman, G.; Bernacchi, C.; Dohleman, F.

    2008-12-01

    Perennial rhizomatous C4 grasses are currently considered one of the most promising vegetation types to accommodate a cellulosic feedstock based liquid fuel economy. The current focus on using these vegetation types as a source of renewable fuel has sparked numerous concerns associated with environmental impacts. Of particular interest is the impact that altering the composition of vegetation at the landscape scale would have on local and regional hydrological cycles. We hypothesize that evapotranspiration, ET, will be higher for perennial grasses relative to maize as a result higher leaf area, higher above-ground biomass and prolonged growing seasons. To test this hypothesis, a technique in which ET is estimated as the residual in the energy balance equation from measurements of net radiation and sensible and latent heat fluxes was employed. Measurements were made during the 2007 growing season for three replicate plots of the perennial rhizomatous grasses Miscanthus giganteus and Panicum virgatum, as well as for Zea mays planted at the University of Illinois South Farms. When averaged across the entire growing season, ET for M. giganteus was double relative to Z. mays, and 130% of P. virgatum ET. When compared over the periods in which all three species experienced mature and closed canopies (from day of year 200 to 250), M. giganteus still showed higher rates of ET compared with Z. mays, however, the increase was only ~15%. We conclude that ET associated with perennial alternative energy crops are higher relative to annual row crop; with most ET disparity, particularly for P. virgatum, being driven by phenology, quicker canopy closure and a prolonged growing season. Physiological rates of ET were highest for M. giganteus, followed by Z. mays, followed P. virgatum. Differences in phenology were more important than those of physiology for ET overshadowing effects from increased biomass associated with M. giganteus and/or a physiological difference between these

  10. Integrated regional modeling assessment of the environmental and economic potential of perennial grass bioenergy feedstocks

    Science.gov (United States)

    Hudiburg, T. W.; Khanna, M.; Dwivedi, P.; Parton, W. J.; Long, S.; Wang, W.; DeLucia, E. H.

    2013-12-01

    Perennial grasses have been proposed as viable bioenergy crops because of their potential to yield harvestable biomass on marginal lands without displacing food and contribute to greenhouse gas (GHG) reduction by storing carbon in soil. Switchgrass, miscanthus, and restored native prairie are among the crops being considered in the corn and agricultural regions of the eastern United States. In this study, we used an extensive dataset of site observations for each of these crops to evaluate and improve a combined ecosystem and economic modeling framework about how both yield and GHG fluxes would respond to different land use strategies. Using this model-data integration approach, we found 30-75% improvement in our predictions over previous studies and good model-data agreement of harvested yields and soil carbon stocks (r2 > 0.62 for all crops). We found that growing perennial grasses would result in average onsite GHG reductions of 0.5-2.0 Mg CO2e ha-1 yr-1compared to a corn-soy baseline, not including fossil fuel offsets. If grown on marginal lands, average onsite GHG reductions remain significant at 0.3-1.0 Mg CO2e ha-1 yr-1. After conversion to bioenergy and complete life cycle assessment, offsite GHG savings can increase by up to 150%, providing a dry biomass supply of 11-22 Mg ha-1 yr-1 for energy use. Preliminary model results of the abatement cost range between 62- 250 per ton of CO2e abated. While a carbon tax would provide an incentive, we find that it would need to be larger than the abatement cost to induce production of cellulosic biofuels.

  11. DEVELOPING HERBACEOUS ENERGY CROPS AS FEEDSTOCKS FOR BIOETHANOL PRODUCTION

    Science.gov (United States)

    Perennial herbaceous crops with high biomass yields are promising substrates for producing bioethnaol. A variety of biomasses including cool and warm season grasses and a legume are being evaluated for this purpose. As a first approach, biomass materials were pretreated with dilute-sulfuric acid a...

  12. Nitrogen accumulation and residual effects of nitrogen catch crops

    DEFF Research Database (Denmark)

    Jensen, E.S.

    1991-01-01

    The nitrogen accumulation in Italian ryegrass (Lolium multiflorum Lam.), perennial ryegrass (Lolium perenne L.), white mustard (Sinapis alba L.) and tansy phacelia (Phacelia tanacetifolia L.), under- or aftersown as nitrogen catch crops to spring barley (Hordeum vulgare L.) and field pea (Pisum s...

  13. 7 CFR 981.19 - Crop year.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Crop year. 981.19 Section 981.19 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 981.19 Crop...

  14. Modelling the carbon and nitrogen balances of direct land use changes from energy crops in Denmark

    DEFF Research Database (Denmark)

    Hamelin, Lorie; Jørgensen, Uffe; Petersen, Bjørn Molt;

    2012-01-01

    rate reductions in response to the absence of tillage for some perennial crops (0%, 25%, 50%). For all crop systems, nutrient balances, balances between above- and below-ground residues, soil carbon changes, biogenic carbon dioxide flows, emissions of nitrogen compounds and losses of macro......This paper addresses the conversion of Danish agricultural land from food/feed crops to energy crops. To this end, a life cycle inventory, which relates the input and output flows from and to the environment of 528 different crop systems, is built and described. This includes seven crops (annuals...

  15. Grass-clover undersowing affects nitrogen dynamics in a grain legume–cereal arable cropping system

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, Henrik; Mundus, Simon; Jensen, Erik Steen

    2012-01-01

    A field experiment was carried out in an arable organic cropping system and included a sequence with sole cropped fababean (Vicia faba L.), lupin (Lupinus angustifolius L.), pea (Pisum sativum L.), oat (Avena sativa L.) and pea–oat intercropping with or without an undersown perennial ryegrass...... N2 fixation and 15N labeling technique to determine the fate of pea and oat residue N recovery in the subsequent crop. The subsequent spring wheat and winter triticale crop yields were not significantly affected by the previous main crop, but a significant effect of catch crop undersowing...

  16. On the use of L-band multipolarization airborne SAR for surveys of crops, vineyards, and orchards in a California irrigated agricultural region

    Science.gov (United States)

    Paris, J. F.

    1985-01-01

    The airborne L-band synthetic aperture radar (SAR) collected multipolarization calibrated image data over an irrigated agricultural test site near Fresno, CA, on March 6, 1984. The conclusions of the study are as follows: (1) the effects of incidence angle on the measured backscattering coefficients could be removed by using a correction factor equal to the secant of the angle raised to the 1.4 power, (2) for this scene and time of year, the various polarization channels were highly correlated such that the use of more than one polarization added little to the ability of the radar to discriminate vegetation type or condition; the exception was barley which separated from vineyards only when a combination of like and cross polarization data were used (polarization was very useful for corn identification in fall crops), (3) an excellent separation between herbaceous vegetation (alfalfa, barley, and oats) or bare fields and trees in orchards existed in brightness was well correlated to alfalfa height or biomass, especially for the HH polarization combination, (5) vineyards exhibited a narrow range of brightnesses with no systematic effects of type or number of stakes nor of number of wires in the trellises nor of the size of the vines, (6) within the orchard classes, areal biomass characterized by basal area differences caused radar image brightness differences for small to medium trees but not for medium to large trees.

  17. Increasing the overwintering survival of container-grown perennials

    OpenAIRE

    Harris, William Kevin

    2011-01-01

    Container grown perennials are a popular product offered by nurseries and greenhouses and included in their production but little research has been reported on proper overwintering techniques for herbaceous perennials and ornamental grasses. In the first experiment rooted liners of Pennisetum alopecuroides, Pennisetum â Hamelnâ and Pennisetum â Little Bunny,â were potted. Treatments included, utilizing two overwintering covers, two fertilizer rates (low or high) and two substrate...

  18. The biology of Mercurialis perennis L. polycormones

    Directory of Open Access Journals (Sweden)

    Krystyna Falińska

    2014-02-01

    Full Text Available The developmental cycle of Mercurialis perennis L. polycormones lasts about 6 years. Under natural conditions polycormones arise by way of vegetative propagation. Their development and growth depend on the age, size and developmental state of the part of the plant from which the new individual arises. Development of the polycormone is most intensive in the first three years. During that time the young individuals increase their number of above-ground and underground shoots according to geometrical progression. A certain stabilization in growth and spread was observed in the 4th and 5th year of life. At that time the polycormones are of spherical or oval shape and their structure is mono- and polycentric. Their surface area is 0.51-2.0 m2 and the number of above-ground shoots amounts to 80-200. In the following years the intensity of regeneration decreases. Polycormones developing in garden culture reach their senile phase in the 3rd and 4th year of life, whereas in natural conditions in the 5th and 6th year. Then gradual dying of the oldest parts of the polycormone starts its division into several independent units. The rapid increase of the area occupied by the newly arising individuals leads to obliteration of the boundaries between them. The development of the aggregation-field distribution specific for this species is preceded by random and aggregation-random distribution of the polycormones in the Tilio-Carpinetum herb layer. It is evaluated that compact one-species patches of Mercurialis parennis L. form in forest communities in about 10 years.

  19. Irrigation Strategies and Crop Breeding As Complementary Measures for Improved Water Management and Ecosystem Services

    Science.gov (United States)

    Vico, G.; Manzoni, S.; Weih, M.; Porporato, A. M.

    2014-12-01

    The projected population growth and changes in climate and dietary habits will further increase the pressure on water resources globally. Within precision farming, a host of technical solutions has been developed to reduce water consumption for agricultural uses. Examples are the shift from scheduled to demand-based irrigation and the use of sophisticated water distribution techniques. The next frontier for a more sustainable agriculture is the combination of reduced water requirements with enhanced ecosystem services. Currently, staple grains are obtained from annuals crops. Enhanced ecosystem services could be obtained shifting from annual to perennial crops, obtained by means of targeted breeding. In fact, perennial plants, with their continuous soil cover and the higher allocation of resources to the below ground, contribute to the reduction of soil erosion, water and nutrient losses, while enhancing carbon sequestration in the root zone. We explore here the implications for water management at the field- to farm-scale of both improved irrigation methods and targeted breeding. A probabilistic description of the soil water balance and crop development is employed to quantify water requirements and yields and their inter-annual variability, as a function of rainfall patterns, soil and crop features. Optimal irrigation strategies are thus defined in terms of maximization of yield and minimization of required irrigation volumes and their inter-annual variability. The probabilistic model is parameterized based on an extensive meta-analysis of traits of co-generic annual and perennial species (including both selected and wild species) to explore the consequences for water requirements of shifting from annual to perennial crops under current and future climates. The larger and more developed roots of perennial crops may allow a better exploitation of soil water resources than annual species. At the same time, perennial crops may require adequate water supply for

  20. Alternative crops

    International Nuclear Information System (INIS)

    Surplus cereal production in the EEC and decreasing product prices, mainly for cereals, has prompted considerable interest for new earnings in arable farming. The objective was to examine whether suggested new crops (fibre, oil, medicinal and alternative grains crops) could be considered as real alternatives. Whether a specific crop can compete economically with cereals and whether there is a market demand for the crop is analyzed. The described possibilities will result in ca. 50,000 hectares of new crops. It is expected that they would not immediately provide increased earnings, but in the long run expected price developments are more positive than for cereals. The area for new crops will not solve the current surplus cereal problem as the area used for new crops is only 3% of that used for cereals. Preconditions for many new crops is further research activities and development work as well as the establishment of processing units and organizational initiatives. Presumably, it is stated, there will then be a basis for a profitable production of new crops for some farmers. (AB) (47 refs.)

  1. California Bioregions

    Data.gov (United States)

    California Department of Resources — California regions developed by the Inter-agency Natural Areas Coordinating Committee (INACC) were digitized from a 1:1,200,000 California Department of Fish and...

  2. Crop Biotechnology

    Science.gov (United States)

    The influence of crop biotechnology on outcomes of agricultural practices and economics is readily evidenced by the escalating acreage of genetically engineered crops, all occurring in a relatively short time span. Until the mid 1990s, virtually no acreage was planted with commercial genetically mo...

  3. Genetic and environmental variation in a commercial breeding program of perennial ryegrass

    DEFF Research Database (Denmark)

    Fé, Dario; Pedersen, Morten Greve; Jensen, Christian S;

    2015-01-01

    Implementation of genomic selection (GS) for the genetic improvement of forage crops, such as perennial ryegrass, requires the establishment of sufficiently large training populations ith high-quality phenotype and genotype data. This paper presents estimates of genetic and environmental variance...... and location), and random effects (breeding values, pedigree or parents, repeated effects of family or parents within location, and within trial environmental effects, to recover interblock information). Results showed very significant genetic variances for all traits, which provide good opportunities...... for future GSbased breeding programs. Forage yield showed family heritabilities of up to 0.30 across locations and up to 0.60 within a location. Similar or moderately lower values were found for the other traits. In particular, the heritabilities of rust resistance and aftermath heading were very...

  4. Host genotype and age shape the leaf and root microbiomes of a wild perennial plant.

    Science.gov (United States)

    Wagner, Maggie R; Lundberg, Derek S; Del Rio, Tijana G; Tringe, Susannah G; Dangl, Jeffery L; Mitchell-Olds, Thomas

    2016-01-01

    Bacteria living on and in leaves and roots influence many aspects of plant health, so the extent of a plant's genetic control over its microbiota is of great interest to crop breeders and evolutionary biologists. Laboratory-based studies, because they poorly simulate true environmental heterogeneity, may misestimate or totally miss the influence of certain host genes on the microbiome. Here we report a large-scale field experiment to disentangle the effects of genotype, environment, age and year of harvest on bacterial communities associated with leaves and roots of Boechera stricta (Brassicaceae), a perennial wild mustard. Host genetic control of the microbiome is evident in leaves but not roots, and varies substantially among sites. Microbiome composition also shifts as plants age. Furthermore, a large proportion of leaf bacterial groups are shared with roots, suggesting inoculation from soil. Our results demonstrate how genotype-by-environment interactions contribute to the complexity of microbiome assembly in natural environments. PMID:27402057

  5. Seasonal versus perennial immunotherapy: evaluation after three years of treatment.

    Science.gov (United States)

    Muñoz Lejarazu, D; Bernaola, G; Fernández, E; Audícana, M; Ventas, P; Martín, S; Fernández de Corres, L

    1993-01-01

    We have performed a comparative study to evaluate seasonal and perennial schedules after 3 years of immunotherapy. Sixty patients suffering from rhinitis and/or asthma due to grass pollen sensitization were randomly allocated to receive a semi-depot extract of Phleum pratense according to a perennial or seasonal schedule. The last year of the study, 14 patients were recruited as a control group without immunotherapy. The cumulative dose was 602 BU in the perennial group and 372 BU in the seasonal group. The frequency and severity of side-effects were similar and very low in both treated groups. The IgE level was significantly lower after perennial immunotherapy at the end of the first 2 years. A seasonal decrease in specific IgG levels was observed in patients who interrupted immunotherapy, while this was not observed in patients under the perennial schedule. Symptoms and medication scores did not show differences between groups. Nevertheless, we found a significant difference between treated patients and the control group. PMID:8281355

  6. Comparative mapping of the wild perennial Glycine latifolia and soybean (G. max) reveals extensive chromosome rearrangements in the genus Glycine.

    Science.gov (United States)

    Chang, Sungyul; Thurber, Carrie S; Brown, Patrick J; Hartman, Glen L; Lambert, Kris N; Domier, Leslie L

    2014-01-01

    Soybean (Glycine max L. Mer.), like many cultivated crops, has a relatively narrow genetic base and lacks diversity for some economically important traits. Glycine latifolia (Benth.) Newell & Hymowitz, one of the 26 perennial wild Glycine species related to soybean in the subgenus Glycine Willd., shows high levels of resistance to multiple soybean pathogens and pests including Alfalfa mosaic virus, Heterodera glycines Ichinohe and Sclerotinia sclerotiorum (Lib.) de Bary. However, limited information is available on the genomes of these perennial Glycine species. To generate molecular resources for gene mapping and identification, high-density linkage maps were constructed for G. latifolia using single nucleotide polymorphism (SNP) markers generated by genotyping by sequencing and evaluated in an F2 population and confirmed in an F5 population. In each population, greater than 2,300 SNP markers were selected for analysis and segregated to form 20 large linkage groups. Marker orders were similar in the F2 and F5 populations. The relationships between G. latifolia linkage groups and G. max and common bean (Phaseolus vulgaris L.) chromosomes were examined by aligning SNP-containing sequences from G. latifolia to the genome sequences of G. max and P. vulgaris. Twelve of the 20 G. latifolia linkage groups were nearly collinear with G. max chromosomes. The remaining eight G. latifolia linkage groups appeared to be products of multiple interchromosomal translocations relative to G. max. Large syntenic blocks also were observed between G. latifolia and P. vulgaris. These experiments are the first to compare genome organizations among annual and perennial Glycine species and common bean. The development of molecular resources for species closely related to G. max provides information into the evolution of genomes within the genus Glycine and tools to identify genes within perennial wild relatives of cultivated soybean that could be beneficial to soybean production. PMID

  7. Comparative mapping of the wild perennial Glycine latifolia and soybean (G. max reveals extensive chromosome rearrangements in the genus Glycine.

    Directory of Open Access Journals (Sweden)

    Sungyul Chang

    Full Text Available Soybean (Glycine max L. Mer., like many cultivated crops, has a relatively narrow genetic base and lacks diversity for some economically important traits. Glycine latifolia (Benth. Newell & Hymowitz, one of the 26 perennial wild Glycine species related to soybean in the subgenus Glycine Willd., shows high levels of resistance to multiple soybean pathogens and pests including Alfalfa mosaic virus, Heterodera glycines Ichinohe and Sclerotinia sclerotiorum (Lib. de Bary. However, limited information is available on the genomes of these perennial Glycine species. To generate molecular resources for gene mapping and identification, high-density linkage maps were constructed for G. latifolia using single nucleotide polymorphism (SNP markers generated by genotyping by sequencing and evaluated in an F2 population and confirmed in an F5 population. In each population, greater than 2,300 SNP markers were selected for analysis and segregated to form 20 large linkage groups. Marker orders were similar in the F2 and F5 populations. The relationships between G. latifolia linkage groups and G. max and common bean (Phaseolus vulgaris L. chromosomes were examined by aligning SNP-containing sequences from G. latifolia to the genome sequences of G. max and P. vulgaris. Twelve of the 20 G. latifolia linkage groups were nearly collinear with G. max chromosomes. The remaining eight G. latifolia linkage groups appeared to be products of multiple interchromosomal translocations relative to G. max. Large syntenic blocks also were observed between G. latifolia and P. vulgaris. These experiments are the first to compare genome organizations among annual and perennial Glycine species and common bean. The development of molecular resources for species closely related to G. max provides information into the evolution of genomes within the genus Glycine and tools to identify genes within perennial wild relatives of cultivated soybean that could be beneficial to soybean

  8. Productivity and carbon footprint of perennial grass-forage legume intercropping strategies with high or low nitrogen fertilizer input

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, Henrik; Lachouani, Petra; Knudsen, Marie Trydeman;

    2016-01-01

    A three-season field experiment was established and repeated twice with spring barley used as cover crop for different perennial grass-legume intercrops followed by a full year pasture cropping and winter wheat after sward incorporation. Two fertilization regimes were applied with plots fertilized...... fertilizer, the forage legume pure stand, especially red clover, was able to produce about 15 t aboveground dry matter ha− 1 year− 1 saving around 325 kg mineral N fertilizer ha− 1 compared to the cocksfoot and tall fescue grass treatments. The pure stand ryegrass yielded around 3 t DM more than red clover...... lowest carbon footprint. Thus, a reduction in N fertilizer application rates in the low input systems offsets increased N2O emissions after forage legume treatments compared to grass plots due to the N fertilizer production-related emissions. When including the subsequent wheat yield in the total...

  9. Genotyping by RAD sequencing enables mapping of fatty acid composition traits in perennial ryegrass (Lolium perenne (L.)).

    Science.gov (United States)

    Hegarty, Matthew; Yadav, Rattan; Lee, Michael; Armstead, Ian; Sanderson, Ruth; Scollan, Nigel; Powell, Wayne; Skøt, Leif

    2013-06-01

    Perennial ryegrass (Lolium perenne L.) is the most important forage crop in temperate livestock agriculture. Its nutritional quality has significant impact on the quality of meat and milk for human consumption. Evidence suggests that higher energy content in forage can assist in reducing greenhouse gas emissions from ruminants. Increasing the fatty acid content (especially α-linolenic acid, an omega-3 fatty acid) may thus contribute to better forage, but little is known about the genetic basis of variation for this trait. To this end, quantitative trait loci (QTLs) were identified associated with major fatty acid content in perennial ryegrass using a population derived from a cross between the heterozygous and outbreeding high-sugar grass variety AberMagic and an older variety, Aurora. A genetic map with 434 restriction-associated DNA (RAD) and SSR markers was generated. Significant QTLs for the content of palmitic (C16:0) on linkage groups (LGs) 2 and 7; stearic (C18:0) on LGs 3, 4 and 7; linoleic (C18:2n-6) on LGs 2 and 5; and α-linolenic acids (C18:3n-3) on LG 1 were identified. Two candidate genes (a lipase and a beta-ketoacyl CoA synthase), both associated with C16:0, and separately with C18:2n-6 and C18:0 contents, were identified. The physical positions of these genes in rice and their genetic positions in perennial ryegrass were consistent with established syntenic relationships between these two species. Validation of these associations is required, but the utility of RAD markers for rapid generation of genetic maps and QTL analysis has been demonstrated for fatty acid composition in a global forage crop. PMID:23331642

  10. Estimated Perennial Streams in Idaho, indexed to the NHDPlus

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Perennial streams in Idaho have been modeled using regression equations for 7-day, 2-year low flows (7Q2) described in Wood and others (2009, U.S. Geological Survey...

  11. Molecular characterization of non-flowering perennial Sorghum spp. hybrids

    Science.gov (United States)

    Seven perennial Sorghum species hybrids were discovered growing in the wild and were collected because all had specific traits, specifically vigor and flowering response, that could be of value in breeding sorghum for bioenergy purposes. Because of the potential of these plants, the objective of th...

  12. Rhetorical Transcendence Revisited: The "Thin Red Line" as Perennial Philosophy.

    Science.gov (United States)

    Stroud, Scott R.

    Fifteen years ago, J. H. Rushing published a seminal article addressing the fragmentation within contemporary society and the ways in which myths (films) may address this exigence. The exigence of fragmentation is relieved, according to her analysis, by mediated recourse to the perennial philosophy of monistic holism that is found across the…

  13. Evaluating perennial sunflower for wildlife and food uses

    Science.gov (United States)

    The objective of this research is to use current genetics and plant breeding techniques to introgress genes for perennial habit from Helianthus tuberosus L. (2n=6x=102) into domesticated sunflower (Helianthus annuus L., 2n=2x=34). H. tuberosusis part of the secondary gene pool of sunflower and has b...

  14. Nitrogen use efficiency in six perennial grasses from contrasting habitats.

    NARCIS (Netherlands)

    Vazquez de Aldana, B.R.; Berendse, F.

    1997-01-01

    1. We studied the nitrogen-use efficiency (NUE) in six perennial grasses adapted to a wide range of nutrient availability. The glasshouse experiment was carried out in pots containing nutrient solution, with two fertility treatments. Nitrogen-use efficiency was considered as the product of nitrogen

  15. Soil C storage and greenhouse gas emission perennial grasses managed for bio energy feedstock

    Science.gov (United States)

    Perennial grasses like switchgrass or big bluestem when managed as bioenergy feedstock require nitrogenous inputs. Nitrogen fertilizer frequently cause nitrous oxide emission. Therefore, managing grasses as feedstock may reduce the greenhouse gas (GHG) mitigation potential expected from perennial. ...

  16. Ionomics: Genes and QTLs controlling heavy metal uptake in perennial grasses grown on phytoxic soil

    Science.gov (United States)

    Perennial grasses occupy diverse soils throughout the world, including many sites contaminated with heavy metals. Uncovering the genetic architecture of QTLs controlling mineral homoeostasis is critical for understanding the biochemical pathways that determine the elemental profiles of perennial pl...

  17. Canaryseed Crop

    Directory of Open Access Journals (Sweden)

    Maximiliano Cogliatti

    2012-03-01

    Full Text Available Canaryseed (Phalaris canariensis L. is a graminaceous crop species with production practices and cycle similar to those of other winter cereal crops such as spring wheat (Triticum aestivum L. and oat (Avena sativa L.. Currently its grains are used almost exclusively as feed for birds, alone or mixed with other grains like millet, sunflower seed, and flaxseed. Canaryseed is a genuine cereal with a unique composition that suggests its potential for food use. P. canariensis is cultivated in many areas of temperate climates. Currently, its production is concentrated in the southwestern provinces of Canada (Alberta, Saskatchewan and Manitoba and on a smaller scale in Argentina, Thailand and Australia. Globally it is considered to be a minor crop with regional relevance, with a production about of 250000 tonnes per year, which restricts private investment and public research on its genetic and technological improvement. For this reason, the type of crop management that is applied to this species largely depends on innovations made in other similar crops. This work provides an updated summary of the available information on the species: its requirements, distribution, genetic resources, cultivation practices, potential uses, marketing and other topics of interest to researchers and producers.

  18. Hemp: A more sustainable annual energy crop for climate and energy policy

    International Nuclear Information System (INIS)

    The objective of this study was to compare the fuel-chain greenhouse gas balance and farm economics of hemp grown for bioenergy with two perennial bioenergy crops, Miscanthus and willow, and two more traditional annual bioenergy crops, sugar beet and oil seed rape (OSR). The GHG burden of hemp cultivation is intermediate between perennial and traditional annual energy crops, but net fuel chain GHG abatement potential of 11 t/CO2 eq./ha/year in the mid yield estimate is comparable to perennial crops, and 140% and 540% greater than for OSR and sugar beet fuel chains, respectively. Gross margins from hemp were considerably lower than for OSR and sugar beet, but exceeded those from Miscanthus when organic fertilizers were used and in the absence of establishment grants for the latter crop. Extrapolated up to the EU scale, replacing 25% of OSR and sugar beet production with hemp production could increase net GHG abatement by up to 21 Mt CO2eq./year. Hemp is a considerably more efficient bioenergy feedstock than the dominant annual energy crops. Integrated into food crop rotations, hemp need not compete with food supplies, and could provide an appealing option to develop more sustainable non-transport bioenergy supply chains. - Highlights: ► The GHG burden of hemp is intermediate between perennial and annual energy crops. ► Replacing 25% of OSR/beet with hemp could increase GHG abatement by 21 Mt/CO2eq./year. ► Hemp is a more efficient bioenergy feedstock than the dominant annual energy crops

  19. Nitrate leaching from organic arable crop rotations is mostly determined by autumn field management

    DEFF Research Database (Denmark)

    Askegaard, M; Olesen, Jørgen E; Rasmussen, Ilse Ankjær;

    2011-01-01

    in the manured treatments the application rate was lower than crop demand. The results identify management of crop and soil during autumn as the main determinant of N leaching. Nitrate leaching was lowest for a catch crop soil cover during autumn and winter (avg. 20 kg N ha−1), a soil cover of weeds......Two main challenges facing organic arable farming are the supply of nitrogen (N) to the crop and the control of perennial weeds. Nitrate leaching from different organic arable crop rotations was investigated over three consecutive four-year crop rotations in a field experiment at three locations...... in Denmark (12 years in total). The experimental treatments were: (i) crop rotation, (ii) catch crop and (iii) animal manure. Nitrate leaching was estimated from measured soil nitrate concentration in ceramic suction cells and modelled drainage. There were significant effects on annual N leaching of location...

  20. IRREVERSIBLE INVESTMENT DECISIONS IN PERENNIAL CROPS WITH YIELD AND PRICE UNCERTAINTY

    OpenAIRE

    Price, T. Jeffrey; Wetzstein, Michael E.

    1999-01-01

    Optimal entry and exit thresholds for Georgia commercial peach production are calculated when both price and yield follow a Brownian motion process. The thresholds are based on an irreversible sunk-cost investment model, where revenue from peach production is affected by the timing of when to enter production. Results indicate stability in Georgia peach production, with growers who are currently producing peaches remaining in production and potential peach growers delaying investment unless t...

  1. Intraspecific variation in thermal acclimation of photosynthesis across a range of temperatures in a perennial crop.

    Science.gov (United States)

    Zaka, Serge; Frak, Ela; Julier, Bernadette; Gastal, François; Louarn, Gaëtan

    2016-01-01

    Interest in the thermal acclimation of photosynthesis has been stimulated by the increasing relevance of climate change. However, little is known about intra-specific variations in thermal acclimation and its potential for breeding. In this article, we examined the difference in thermal acclimation between alfalfa (Medicago sativa) cultivars originating from contrasting origins, and sought to analyze the mechanisms in play. A series of experiments was carried out at seven growth temperatures between 5 and 35 °C using four cultivars from temperate and Mediterranean origin. Leaf traits, the photosynthetic rate at 25 °C (A400 (25)), the photosynthetic rate at optimal temperature (A400 (opt)), the thermal optimum of photosynthesis (Topt), and the photosynthetic parameters from the Farqhuar model were determined. Irrespective of cultivar origin, a clear shift in the temperature responses of photosynthesis was observed as a function of growth temperature, affecting thermal optimum of photosynthesis, photosynthetic rate at optimal temperature and photosynthetic rate at 25 °C. For both cultivars, Topt values increased linearly in leaves grown between 5 and 35 °C. Relative homeostasis of A400 (25) and A400 (opt) was found between 10 °C and 30 °C growth temperatures, but sharp declines were recorded at 5 and 35 °C. This homeostasis was achieved in part through modifications to leaf nitrogen content, which increased at extreme temperatures. Significant changes were also recorded regarding nitrogen partitioning in the photosynthetic apparatus and in the temperature dependence of photosynthetic parameters. The cultivars differed only in terms of the temperature response of photosynthetic parameters, with Mediterranean genotypes displaying a greater sensitivity of the maximum rate of Rubisco carboxylation to elevated temperatures. It was concluded that intra-specific variations in the temperature acclimation of photosynthesis exist among alfalfa cultivars, but that Mediterranean genotypes presented no evidence of superior performance at high temperatures. PMID:27178065

  2. Intraspecific variation in thermal acclimation of photosynthesis across a range of temperatures in a perennial crop

    Science.gov (United States)

    Zaka, Serge; Frak, Ela; Julier, Bernadette; Gastal, François; Louarn, Gaëtan

    2016-01-01

    Interest in the thermal acclimation of photosynthesis has been stimulated by the increasing relevance of climate change. However, little is known about intra-specific variations in thermal acclimation and its potential for breeding. In this article, we examined the difference in thermal acclimation between alfalfa (Medicago sativa) cultivars originating from contrasting origins, and sought to analyze the mechanisms in play. A series of experiments was carried out at seven growth temperatures between 5 and 35 °C using four cultivars from temperate and Mediterranean origin. Leaf traits, the photosynthetic rate at 25 °C (A40025), the photosynthetic rate at optimal temperature (A400opt), the thermal optimum of photosynthesis (Topt), and the photosynthetic parameters from the Farqhuar model were determined. Irrespective of cultivar origin, a clear shift in the temperature responses of photosynthesis was observed as a function of growth temperature, affecting thermal optimum of photosynthesis, photosynthetic rate at optimal temperature and photosynthetic rate at 25 °C. For both cultivars, Topt values increased linearly in leaves grown between 5 and 35 °C. Relative homeostasis of A40025 and A400opt was found between 10 °C and 30 °C growth temperatures, but sharp declines were recorded at 5 and 35 °C. This homeostasis was achieved in part through modifications to leaf nitrogen content, which increased at extreme temperatures. Significant changes were also recorded regarding nitrogen partitioning in the photosynthetic apparatus and in the temperature dependence of photosynthetic parameters. The cultivars differed only in terms of the temperature response of photosynthetic parameters, with Mediterranean genotypes displaying a greater sensitivity of the maximum rate of Rubisco carboxylation to elevated temperatures. It was concluded that intra-specific variations in the temperature acclimation of photosynthesis exist among alfalfa cultivars, but that Mediterranean genotypes presented no evidence of superior performance at high temperatures. PMID:27178065

  3. An Assessment of Bio-Energy Crops Use in Illinois

    Science.gov (United States)

    Jain, A.; Khanna, M.; Barman, R.; Yang, X.; Dhungana, B.; Chen, X.

    2007-12-01

    Growing concern about climate change and energy security has led to increasing interest in developing domestically available renewable energy sources for meeting the electricity, heating and fuel needs in the United States. Illinois has a significant potential to grow perennial grasses that can provide bio-energy. Two perennial grasses, Switchgrass and Miscanthus, have been identified as among the best choices for low input bio-energy production in the US and Europe. The purpose of this talk is two fold. First, we will examine the optimal areas in Illinois to locate perennial grasses as feedstocks. These areas will be determined based on biophysical conditions (such as heterogeneity in soil quality and climatic factors) and costs of production and costs of land that differ across locations. Second, we will determine the CO2 mitigation benefits to be provided by bioenergy crops, both in the form of soil carbon sequestration and displacement of carbon emissions from gasoline. This analysis will be undertaken using detailed GIS data on soil quality, climate and land use for 0.1deg by 0.1deg grid cells in Illinois. This data will be used together with the Integrated Science Assessment Model (ISAM), a terrestrial ecosystem model, to estimate the yields of Switchgrass and Miscanthus as well as their potential to sequester carbon in the soil. Yield for row crops will be based on historical data and will be used to determine the opportunity cost of converting land currently under corn and soybean production to perennial grasses. Costs of production for the alternative crops here include expenses incurred by farmers on fertilizer inputs, machinery, harvesting and transportation and will be used to determine the profitability of alternative land uses in each grid cell. The framework developed here will be used to examine the optimal locations to grow bio-energy crops to achieve various carbon mitigation targets cost-effectively.

  4. Litter Inputs and Soil Aggregation in Midwestern Biofuel Crops

    Science.gov (United States)

    Kantola, I. B.; Masters, M. D.; Smyth, E. M.; DeLucia, E. H.

    2014-12-01

    Perennial C4 grasses represent alternatives to corn for the production of ethanol because of low management costs and high biomass production. To evaluate the effects of perennial grasses on the agricultural soils of the Midwest, native switchgrass and a sterile hybrid of the Asian grass Miscanthus were planted at the University of Illinois Energy Farm in 2008. Through five years of growth, above and belowground plant biomass, litter, and soil were compared with soils in plots growing a corn-corn-soy rotation typical of the area. Above- and belowground plant biomass in Miscanthus and switchgrass averaged higher than corn/soy following two years of perennial establishment, with belowground biomass exceeding corn/soy by approximately 5-fold in the year after establishment (2010) and 25-fold by 2012. Measurements of root distribution and turnover rates indicate that roots are the primary contribution of new carbon to soils under perennial crops. Physical fractionation of the soils into water stable aggregates showed 4-14% increases in macroaggregate fractions under perennial crops; the large aggregates are adhered together by organic material and indicative of the increased presence of labile carbon forms like plant roots, fungi, and plant and microbial exudates. Carbon and nitrogen analyses of the fractions show that while overall carbon has not increased significantly in whole soil, soils under perennial grasses are concentrating carbon by 5-17% in the macroaggregates after just 5 years. Native switchgrass roots (buried) and litter (surface-applied) decompose faster than Miscanthus roots and litter, but slower than corn roots and litter buried to simulate incorporation by tillage. Switchgrass soil shows the highest degree of macroaggregate formation, pointing to a high rate of litter and root decomposition and incorporation into soil structure. While macroaggregates are relatively labile soil structures compared to microaggregates and free silt and clay, they offer

  5. Precision overhead irrigation is suitable for several Central Valley crops

    Directory of Open Access Journals (Sweden)

    Jeffrey P. Mitchell

    2016-04-01

    Full Text Available Overhead systems are the dominant irrigation technology in many parts of the world, but they are not widely used in California even though they have higher water application efficiency than furrow irrigation systems and lower labor requirements than drip systems. With water and labor perennial concerns in California, the suitability of overhead systems merits consideration. From 2008 through 2013, in studies near Five Points, California, we evaluated overhead irrigation for wheat, corn, cotton, tomato, onion and broccoli as an alternative to furrow and drip irrigation. With the exception of tomato, equal or increased yields were achieved with overhead irrigation. Many variables are involved in the choice of an irrigation system, but our results suggest that, with more research to support best management practices, overhead irrigation may be useful to a wider set of California farmers than currently use it.

  6. A rapidly declining perennial sea ice cover in the Arctic

    Science.gov (United States)

    Comiso, Josefino C.

    2002-10-01

    The perennial sea ice cover in the Arctic is shown to be declining at -9% per decade using satellite data from 1978 to 2000. A sustained decline at this rate would mean the disappearance of the multiyear ice cover during this century and drastic changes in the Arctic climate system. An apparent increase in the fraction of second year ice in the 1990s is also inferred suggesting an overall thinning of the ice cover. Surface ice temperatures derived from satellite data are negatively correlated with perennial ice area and are shown to be increasing at the rate of 1.2 K per decade. The latter implies longer melt periods and therefore decreasing ice volume in the more recent years.

  7. A mowing strategy to convert red clover to annual crops in organic farming

    Science.gov (United States)

    Organic producers are interested in no-till cropping systems. In this study, we found that perennial clover can be converted to corn without tillage. Conversion tactics involved fall mowing in the third year of red clover, followed by between-row mowing of weeds and volunteer red clover in corn gr...

  8. Inflorescence characteristics, seed composition, and allometric relationships predicting seed yields in the biomass crop Cynara cardunculus

    NARCIS (Netherlands)

    Archontoulis, S.V.; Struik, P.C.; Yin, X.; Bastiaans, L.; Vos, J.; Danalatos, N.G.

    2010-01-01

    Cynara (Cynara cardunculus) is a perennial C3 herb that has its potential as bioenergy crop. This paper aims (a) to derive empirical relationships to predict cynara seed yield per head and per unit area, avoiding laborious extraction of seeds from the complex structure of its inflorescences; (b) to

  9. Photosynthesis in tropical cover crop legumes influenced by irradiance, external carbon dioxide concentration and temperature

    Science.gov (United States)

    In plantation crops perennial tropical legumes are grown as understory plants, receive limited irradiance, and are subjected to elevated levels of CO2 and temperature. Independent short-term effects of photosynthetic photon flux density (PPFD), external carbon dioxide concentration [CO2] and temper...

  10. Linking Resilience Theory and Diffusion of Innovations Theory to Understand the Potential for Perennials in the U.S. Corn Belt

    Directory of Open Access Journals (Sweden)

    Lynne M. Westphal

    2009-06-01

    Full Text Available In the last 200 yr, more than 80% of the land in the U.S. Corn Belt agro-ecosystem has been converted from natural perennial vegetation to intensive agricultural production of row crops. Despite research showing how re-integration of perennial vegetation, e.g., cover crops, pasture, riparian buffers, and restored wetlands, at strategic landscape positions can bolster declining regional ecosystem functions, the amount of land area devoted to row crop production in the Corn Belt continues to increase. As this region enters a time of fast-paced and uncertain reorganization driven by the emerging bioeconomy, changes in land use will continue to take place that will impact the resilience of the Corn Belt’s linked social and ecological systems for years to come. Both resilience theory and the diffusion of innovations theory investigate how change is brought about in systems through the adaptation and innovation of social actors. In this paper, we integrate these two frameworks in the analysis of 33 in-depth interviews to improve our understanding of how rural Corn Belt stakeholders make conservation decisions in the midst of an uncertain future. Interview data indicate that the adoption of conservation practices is based not only on immediate profitability but also on the interplay between contextual factors at three distinct levels of the system: compatibility with farm priorities, profitability, practices, and technologies; community-level reinforcement through local social networks, norms, and support structures; and consistent, straightforward, flexible, and well-targeted incentives and regulations issuing from regional institutions. Interviewees suggest that the multiscale drivers that currently support the continued expansion of row crop production could be realigned with conservation objectives in landscapes of the future. Adaptation of social actors through collaborative learning at the community level may be instrumental in brokering the

  11. Source of variation of isoflavone concentrations in perennial clover species

    OpenAIRE

    Bronislava Butkute; Butkute Lemeziene; Giedre Dabkeviciene; Valdas Jakstas; Egidijus Vilcinskas; Valdimaras Janulis

    2014-01-01

    Introduction: Clover has attracted considerable interest not only as a valuable livestock forage plant, but also as an important source of isoflavones. The current study was aimed to assess the variation of concentration of three isoflavones in clover species grown under a cool temperate climate environment in Lithuania. Materials and Methods: Isoflavone contents were quantified in the plant parts of 21 accessions belonging to five perennial species of genus Trifolium (T. pratense, T. repens,...

  12. Molecular Characterization of Non-flowering Perennial Sorghum spp. Hybrids

    OpenAIRE

    Jessup, R. W.; Whitmire, D. K.; Farrow, Z. L.; Burson, B. L.

    2011-01-01

    Aims: The goal of this study was to characterize recently identified, non-flowering, putative tetraploid Sorghum spp. hybrids utilizing bulked segregant analysis with SSRs and compare them to S. bicolor, S. halepense, and triploid putative Sorghum spp. hybrids. Confirmed species hybrids between S. bicolor and S. halepense would provide resources for investigating risks of invasiveness and transgene escape alongside potential for identifying novel perennial Sorghum feedstocks of value. Study d...

  13. 7 CFR 993.20 - Crop year.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Crop year. 993.20 Section 993.20 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE DRIED PRUNES PRODUCED IN CALIFORNIA Order Regulating Handling Definitions §...

  14. 7 CFR 987.6 - Crop year.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Crop year. 987.6 Section 987.6 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE DOMESTIC DATES PRODUCED OR PACKED IN RIVERSIDE COUNTY, CALIFORNIA Order...

  15. 7 CFR 989.21 - Crop year.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Crop year. 989.21 Section 989.21 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES GROWN IN CALIFORNIA Order Regulating...

  16. Development and annotation of perennial Triticeae ESTs and SSR markers.

    Science.gov (United States)

    Bushman, B Shaun; Larson, Steve R; Mott, Ivan W; Cliften, Paul F; Wang, Richard R-C; Chatterton, N Jerry; Hernandez, Alvaro G; Ali, Shahjahan; Kim, Ryan W; Thimmapuram, Jyothi; Gong, George; Liu, Lei; Mikel, Mark A

    2008-10-01

    Triticeae contains hundreds of species of both annual and perennial types. Although substantial genomic tools are available for annual Triticeae cereals such as wheat and barley, the perennial Triticeae lack sufficient genomic resources for genetic mapping or diversity research. To increase the amount of sequence information available in the perennial Triticeae, three expressed sequence tag (EST) libraries were developed and annotated for Pseudoroegneria spicata, a mixture of both Elymus wawawaiensis and E. lanceolatus, and a Leymus cinereus x L. triticoides interspecific hybrid. The ESTs were combined into unigene sets of 8 780 unigenes for P. spicata, 11 281 unigenes for Leymus, and 7 212 unigenes for Elymus. Unigenes were annotated based on putative orthology to genes from rice, wheat, barley, other Poaceae, Arabidopsis, and the non-redundant database of the NCBI. Simple sequence repeat (SSR) markers were developed, tested for amplification and polymorphism, and aligned to the rice genome. Leymus EST markers homologous to rice chromosome 2 genes were syntenous on Leymus homeologous groups 6a and 6b (previously 1b), demonstrating promise for in silico comparative mapping. All ESTs and SSR markers are available on an EST information management and annotation database (http://titan.biotec.uiuc.edu/triticeae/). PMID:18923529

  17. A transcriptome map of perennial ryegrass (Lolium perenne L.

    Directory of Open Access Journals (Sweden)

    Studer Bruno

    2012-04-01

    Full Text Available Abstract Background Single nucleotide polymorphisms (SNPs are increasingly becoming the DNA marker system of choice due to their prevalence in the genome and their ability to be used in highly multiplexed genotyping assays. Although needed in high numbers for genome-wide marker profiles and genomics-assisted breeding, a surprisingly low number of validated SNPs are currently available for perennial ryegrass. Results A perennial ryegrass unigene set representing 9,399 genes was used as a reference for the assembly of 802,156 high quality reads generated by 454 transcriptome sequencing and for in silico SNP discovery. Out of more than 15,433 SNPs in 1,778 unigenes fulfilling highly stringent assembly and detection parameters, a total of 768 SNP markers were selected for GoldenGate genotyping in 184 individuals of the perennial ryegrass mapping population VrnA, a population being previously evaluated for important agronomic traits. A total of 592 (77% of the SNPs tested were successfully called with a cluster separation above 0.9. Of these, 509 (86% genic SNP markers segregated in the VrnA mapping population, out of which 495 were assigned to map positions. The genetic linkage map presented here comprises a total of 838 DNA markers (767 gene-derived markers and spans 750 centi Mogan (cM with an average marker interval distance of less than 0.9 cM. Moreover, it locates 732 expressed genes involved in a broad range of molecular functions of different biological processes in the perennial ryegrass genome. Conclusions Here, we present an efficient approach of using next generation sequencing (NGS data for SNP discovery, and the successful design of a 768-plex Illumina GoldenGate genotyping assay in a complex genome. The ryegrass SNPs along with the corresponding transcribed sequences represent a milestone in the establishment of genetic and genomics resources available for this species and constitute a further step towards molecular breeding

  18. Sustainable commercialization of new crops for the agricultural bioeconomy

    Directory of Open Access Journals (Sweden)

    N.R. Jordan

    2016-01-01

    Full Text Available Abstract Diversification of agroecological systems to enhance agrobiodiversity is likely to be critical to advancing environmental, economic, and social sustainability of agriculture. Temperate-zone agroecological systems that are currently organized for production of summer-annual crops can be diversified by integration of fallow-season and perennial crops. Integration of such crops can improve sustainability of these agroecological systems, with minimal interference with current agricultural production. Importantly, these crops can provide feedstocks for a wide range of new bio-products that are forming a new agricultural bioeconomy, potentially providing greatly increased economic incentives for diversification. However, while there are many fallow-season and perennial crops that might be used in such a “bioeconomic” strategy for diversification, most are not yet well adapted and highly-marketable. Efforts are underway to enhance adaptation and marketability of many such crops. Critically, these efforts require a strategic approach that addresses the inherent complexity of these projects. We outline a suitable approach, which we term “sustainable commercialization”: a coordinated innovation process that integrates a new crop into the agriculture of a region, while intentionally addressing economic, environmental and social sustainability challenges via multi-stakeholder governance. This approach centers on a concerted effort to coordinate and govern innovation in three critical areas: germplasm development, multifunctional agroecosystem design and management, and development of end uses, supply chains, and markets. To exemplify the approach, we describe an ongoing effort to commercialize a new fallow-season crop, field pennycress (Thlaspi arvense L..

  19. Influence of crop rotation, intermediate crops, and organic fertilizers on the soil enzymatic activity and humus content in organic farming systems

    Science.gov (United States)

    Marcinkeviciene, A.; Boguzas, V.; Balnyte, S.; Pupaliene, R.; Velicka, R.

    2013-02-01

    The influence of crop rotation systems with different portions of nitrogen-fixing crops, intermediate crops, and organic fertilizers on the enzymatic activity and humus content of soils in organic farming was studied. The highest activity of the urease and invertase enzymes was determined in the soil under the crop rotation with 43% nitrogen-fixing crops and with perennial grasses applied twice per rotation. The application of manure and the growing of intermediate crops for green fertilizers did not provide any significant increase in the content of humus. The activity of urease slightly correlated with the humus content ( r = 0.30 at the significance level of 0.05 and r = 0.39 at the significance level of 0.01).

  20. California Air Basins

    Data.gov (United States)

    California Department of Resources — Air ResourcesCalifornia Air Resources BoardThe following datasets are from the California Air Resources Board: * arb_california_airbasins - California Air BasinsThe...

  1. Perennial atopic rhinitis as an early stage of bronchial asthma.

    Science.gov (United States)

    Gniazdowski, R

    1979-01-01

    Etiologic factors and incidence of bronchial hyperreactivity as a 'stigma' of bronchial asthma were studied in 237 patients suffering from perennial atopic rhinitis. All pateints underwent detailed laryngologic and allergologic examiniation and pulmonary function tests at rest, after exercise, and after histamine inhalation. Most often the patients were sensitized tungal allergens. Bronchial hyperreactivity, typical of bronchial asthma, was observed in 48.52% of patients. Results were analysed statistically. It was concluded that early institution of causal therapy can cure the symptoms of rhinitis and prevent evolution of the disease into atopic bronchial asthma in patients already suffering from bronchial hyperreactivity. PMID:495074

  2. Genotype variation of perennial ryegrass grown for seed

    DEFF Research Database (Denmark)

    Abel, Simon; Boelt, Birte

    2016-01-01

    There is a large source of untapped variation within perennial ryegrass (Lolium perenne L.) populations that may increase seed yields. Understanding this variation starts with the development of potentials seed yield and how the length of this period may change with cultivar. Utilising 53 UPOV...... for the range of cultivars modelled. We show that in later secondary inducing cultivars, there is a reduced period for the development of seed yield potential. The results have wider implications for seed production management systems, with research trials needing to comprehend if the varying inputs...... alter the development of seed yield potential, or the utilisation of seed yield potentials....

  3. Kesatuan Agama-agama dan Kearifan Perennial dalam Perspektif Tasawuf

    Directory of Open Access Journals (Sweden)

    Armia Armia

    2013-05-01

    Full Text Available Abstract: All religions, if we try to find their core teachings, we will find the same messages, namely the realization of peace, goodness, and happiness to mankind. No religion teaches violence and savagery. This confirms that theologically religion is very much interested in the realization of human well-being in life. Thus, peace must be a meeting point for all religions to implement in social life. This paper explored the Sufi’s view of the nature of God, religion, and the perennial wisdom based on the principle of spirituality and love (mahabbah.

  4. Performance of lactating dairy cows fed alfalfa silage or perennial ryegrass silage.

    Science.gov (United States)

    Hoffman, P C; Combs, D K; Casler, M D

    1998-01-01

    The nutrient contents of perennial ryegrass (Lolium perenne L.) and alfalfa (Medicago sativa L.) are reasonably similar. Despite similarities, the lactation performance of dairy cows fed perennial ryegrass has not been compared with the lactation performance of dairy cows fed alfalfa. The present study was implemented to compare the performance of lactating cows fed alfalfa or perennial ryegrass silage. Alfalfa and perennial ryegrass were harvested at late bud and boot stages of maturity, respectively, and ensiled in separate 4.9- x 18.3-m concrete silos. The experimental silages were supplemented with a concentrate mix at 31.1% of dietary dry matter and fed to 18 multiparous Holstein cows in early lactation in a crossover experimental design with 28-d periods. Digestibility and rate of passage of experimental diets were also measured using rare earth markers. The perennial ryegrass contained 3.0 percentage units more neutral detergent fiber than did alfalfa, but in vitro digestibility of neutral detergent fiber was 8.8 percentage units higher for perennial ryegrass. In vitro digestibility of dry matter was also higher for perennial ryegrass. Cows fed alfalfa silage produced more milk (31.8 kg/d) than did cows fed perennial ryegrass silage (30.2 kg/d). Cows fed perennial ryegrass silage ate less feed (2.2 kg/d) than did cows fed alfalfa. Because dry matter intake was lower, diet digestibilities were higher, and rate of passage was slower, for cows consuming perennial ryegrass. Based on laboratory evaluations, perennial ryegrass silage has high nutritional quality, but performance of lactating cows indicated that the forage was suboptimal for supporting high milk production when compared with alfalfa. The perennial ryegrass silage was suboptimal because it did not stimulate high amounts of dry matter intake in lactating cows. PMID:9493091

  5. A review of soil erosion potential associated with biomass crops

    International Nuclear Information System (INIS)

    It has been estimated that up to 60 million hectares could be devoted to energy crop production in the U.S. Due to economic considerations, biomass crops will probably be produced on marginal cropland which is frequently highly erodible. Thus, the impact of herbaceous and woody biomass crop production on soil erosion must be addressed. Perennial grasses provide year-round soil cover, limiting erosion even with continued biomass harvest. Vigorous perennial herbaceous stands reduce water runoff and sediment loss and favor soil development processes by improving soil organic matter, soil structure and soil water and nutrient-holding capacity. Minimum tillage management of row crops reduces erosion compared with systems involving more frequent or more extensive tillage. Woody biomass plantations reduce water erosion by improving water infiltration, reducing impacts by water droplets, intercepting rain and snow and physically stabilizing soil by their roots and leaf litter. Shelterbelts reduce wind erosion when planted as shelterbelts and improve soil organic matter, soil structure and soil moisture in their leeward zone, reducing soil erodibility. Harvesting of woody biomass plantations may be accompanied by increased erosion. Forestry clear-cutting, especially on steep slopes, often results in a large increase in water erosion. For this reason, it is essential that woody biomass plantations be designed for rotational harvesting, even though this may result in higher harvesting costs. (Author)

  6. Dubious battle in California Dubious battle in California

    Directory of Open Access Journals (Sweden)

    John Steinbeck

    2008-04-01

    Full Text Available In sixty years a complete revolution has taken place in California agriculture. Once its principal products were hay and cattle. Today fruits and vegetables are its most profitable crops. With the change in the nature of farming there has come a parallel change in the nature and amount of the labor necessary to carry it on. Truck gardens, while they give a heavy yield per acre, require much more labor and equipment than the raising of hay and livestock. At the same time these crops are seasonal, which means that they are largely handled by migratory workers. Along with the intensification of farming made necessary by truck gardening has come another important development. In sixty years a complete revolution has taken place in California agriculture. Once its principal products were hay and cattle. Today fruits and vegetables are its most profitable crops. With the change in the nature of farming there has come a parallel change in the nature and amount of the labor necessary to carry it on. Truck gardens, while they give a heavy yield per acre, require much more labor and equipment than the raising of hay and livestock. At the same time these crops are seasonal, which means that they are largely handled by migratory workers. Along with the intensification of farming made necessary by truck gardening has come another important development.

  7. Soil carbon changes in a wetness-prone perennial grass bioenergy field of Northeastern United States.

    Science.gov (United States)

    Das, S.; Thomas, R. E.; Steenhuis, T. S.; Walter, M. F.; Richards, B. K.

    2015-12-01

    In Northeastern United States, fallow marginal lands are being cited as a resource base for the perennial bioenergy sector. Many soils in this region are unsuitable (hence marginal) for row crop agriculture due to seasonal water saturation or near-saturation. Potential carbon (C) sequestration is a key ecosystem service of perennial bioenergy systems. The research site is a 16 acre field (42N28.20', 76W25.94') with predominantly Canaseraga-Dalton-Madalin soils, which was fallow for more than 50 years before establishment in 2011. Quadruplicate treatments have been established on test strips (~1 acre) in which soil moisture conditions vary naturally from moderately well-drained to poorly drained. 16 strip plots consist of the treatments: switchgrass, switchgrass +fertilizer N, reed canarygrass +N, and pre-existing grass as control. The N fertilization rate is 66 lb/ac. 5 permanent sampling subplots were established along the natural moisture gradient of each plot, based on initial water content measurements at the soil surface (0-12 cm) by time-domain reflectometry (TDR). Thus, 80 permanent sampling points have been established, where soil C and health parameters viz soil aggregate stability, permanganate-oxidizable (POX) carbon etc and biomass yields are sampled yearly. Frequent TDR measurements have been normalized to determine relative wetness of all 80 subplots, which have been grouped under five wetness quintiles. The driest subplots are approximately 0.8 times the field mean, whereas the wettest subplots are 1.3 times of that. After four years of establishment, the yields, % SOC (combustion method) and C/N ratios have been plotted. The decrease in % organic matter (loss on ignition) over this time for control soils, wetness quintiles 1 through 5 ranged from 2.05 ( std dev 1.9) to 1.24 (0.39), for reed canary grass soils, from3.37(1.33) to 1.59 (1.03), for switchgrass soils, from 2.67 (0.43) to 1.28 (0.91) and for switchgrass+N soils, from 2.63(0.47) to 2

  8. Symbiotic N2-fixation by the cover crop Pueraria phaseoloides as influenced by litter mineralization

    DEFF Research Database (Denmark)

    Vesterager, J.M.; Østerby, S.; Jensen, E.S.;

    1995-01-01

    The perennial legume Pueraria phaseoloides is widely used as a cover crop in rubber and oil palm plantations. However, very little knowledge exists on the effect of litter mineralization from P. phaseoloides on its symbiotic N-2- fixation. The contribution from symbiotic N-2-fixation (Ndfa...

  9. A Mobile Field Robot with Vision-Based Detection of Volunteer Potato Plants in a Corn Crop

    NARCIS (Netherlands)

    Evert, van F.K.; Heijden, van der G.W.A.M.; Lotz, L.A.P.; Polder, G.; Lamaker, A.; Jong, de A.; Kuyper, M.C.; Groendijk, E.J.K.; Neeteson, J.J.; Zalm, van der A.J.A.

    2006-01-01

    Volunteer potato is a perennial weed that is difficult to control in crop rotations. It was our objective to build a small, low-cost robot capable of detecting volunteer potato plants in a cornfield and thus demonstrate the potential for automatic control of this weed. We used an electric toy truck

  10. Impacts of Past Land Use Changes on Water Resources: An Analog for Assessing Effects of Proposed Bioenergy Crops

    Science.gov (United States)

    Scanlon, B. R.; Schilling, K.; Young, M.; Duncan, I. J.; Gerbens-Leenes, P.

    2011-12-01

    Interest is increasing in renewable energy sources, including bioenergy. However, potential impacts of bioenergy crops on water resources need to be better understood before large scale expansion occurs. This study evaluates the potential for using past land use change impacts on water resources as an analog for assessing future bioenergy crop effects. Impacts were assessed for two cases and methods: (1) changes from perennial to annual crops in the Midwest U.S. using stream hydrograph separation; and (2) changes from perennial grasses and shrubs to annual crops in the Southwest U.S. using unsaturated zone and groundwater data. Results from the Midwest show that expanding the soybean production area by 80,000 km2 increased stream flow by 32%, based on data from Keokuk station in the Upper Mississippi River Basin. Using these relationships, further expansion of annual corn production for biofuels by 10 - 50% would increase streamflow by up to 40%, with related increases in nitrate, phosphate, and sediment pollutant transport to the Gulf of Mexico. The changes in water partitioning are attributed to reducing evapotranspiration, increasing recharge and baseflow discharge to streams. Similar results were found in the southwestern US, where changes from native perennial grasses and shrubs to annual crops increased recharge from ~0.0 to 24 mm/yr, raising water tables by up to 7 m in some regions and flushing accumulated salts into underlying aquifers in the southern High Plains. The changes in water partitioning are related to changes in rooting depth from deep rooted native vegetation to shallow rooted crops and growing season length. Further expansion of annual bioenergy crops, such as changes from Conservation Reserve Program to corn in the Midwest, will continue the trajectory of reducing ET, thereby increasing recharge and baseflow to streams and nutrient export. We hypothesize that changing bioenergy crops from annual crops to perennial grasses, such as switchgrass

  11. Tracking Changes in Dissolved Organic Matter Patterns in Perennial Headwater Streams Throughout a Hydrologic Year Using In-situ Sensors and Optical Properties

    Science.gov (United States)

    Armstrong, A.; Epting, S.; Hosen, J. D.; Palmer, M.

    2015-12-01

    Dissolved organic matter (DOM) plays a central role in freshwater streams but key questions remain unanswered about temporal patterns in its quantity and composition. DOM in perennial streams in the temperate zone is a complex mixture reflecting a variety of sources such as leached plant material, organic matter from surrounding soils, and microbial processes in the streams themselves. Headwater perennial streams in the Tuckahoe Creek watershed of the Atlantic coastal plain (Maryland, USA) drain a mosaic of land cover types including row crops, forests, and both forested and marshy small depressional wetlands. Wetland-stream surface hydrologic connections generally occur between mid-fall and late spring, coinciding with peak wetland hydrologic expression (i.e. highest groundwater levels and surface inundation extent). When inundated, these wetlands contain high DOM concentrations, and surface connections may serve as conduits for downstream export. We hypothesized that changes in wetland-stream surface hydrologic connectivity would affect patterns of DOM concentration and composition in these streams. We deployed 6 sondes equipped with fluorescent DOM sensors in 4 perennial streams, 1 forested wetland, and the larger downstream channel draining all study sites for the 2015 water year. The 4 headwater streams drain areas containing forested wetlands and have documented temporary channel connections. Combined with baseflow and stormflow sampling, the sondes provided 15 minute estimates of dissolved organic carbon (DOC) concentrations. This resolution provided insights into patterns of DOC concentration across temporal scales from daily rhythms to seasonal changes, during both baseflow and storm conditions. Discrete measurements of absorbance and fluorescence provided information about DOM composition throughout the study. Together these measurements give a detailed record of DOM dynamics in multiple perennial headwater streams for an entire year. This information

  12. Producing bulbs and perennials : sustainable control of diseases, pests and weeds

    NARCIS (Netherlands)

    Boer, de M.

    2011-01-01

    In the Netherlands every year flower bulbs and perennials are produced representing a value of € 500 m (flower bulbs) and of € 65 m (perennials, 2004). The growers are faced with several threatening pests and diseases during the production. They usually deal with these problems by using pesticides.

  13. Perennial ryegrass for dairy cows: Grazing behaviour, intake, rumen function and performance

    NARCIS (Netherlands)

    Taweel, H.Z.

    2004-01-01

    Keywords: Dairy cows, Perennial ryegrass, Rumen fill, Clearance, Degradation, Grazing behaviour.In temperate environments, perennial ryegrass is the most widely used species for feeding dairy cows. That is because of its high productivity, palatability, digestibility and nutritive

  14. Control of perennial weeds by mechanical methods and anaerobic soil disinfection

    NARCIS (Netherlands)

    Huiting, H.F.; Bleeker, P.O.; Riemens, M.M.

    2011-01-01

    Perennial weeds are difficult to control and ask for a specific approach. During the most recent years it has even become a great challenge to control these weeds in conventional farming systems, although in comparison effective perennial weed control in organic farming systems remains more difficul

  15. Perennial ryegrass for dairy cows: effects of cultivar on herbage intake during grazing

    NARCIS (Netherlands)

    Smit, H.J.

    2005-01-01

    Keywords:Perennial ryegrass, Lolium perenne , sward morphology, sward cutting, n-alkanes, herbage intake, selection, preference.Perennial ryegrass ( Lolium perenne L.) is the most important species for feeding dairy cows. The majority of the farmers in the Netherlands graze their d

  16. Soil Organic Carbon Pools Under Switchgrass Grown as a Bioenergy Crop Compared to Other Conventional Crops

    Institute of Scientific and Technical Information of China (English)

    F.G.DOU; F.M.HONS; W.R.OCUMPAUGH; J.C.READ; M.A.HUSSEY; J.P.MUIR

    2013-01-01

    Switchgrass (Panicum virgatum L.) has been proposed as a sustainable bioenergy crop because of its high yield potential,adaptation to marginal sites,and tolerance to water and nutrient limitations.A better understanding of the potential effects of biomass energy crop production practices on soil biological properties and organic matter dynamics is critical to its production.Our objective was to evaluate changes in C pools under a warm-season perennial switchgrass in different soils compared to typically-grown crops collected at College Station,Dallas,and Stephenville,TX in February 2001.Sampling depths were 0-5,5-15,and 15-30 cm.Switchgrass increased soil organic C (SOC),soil microbial biomass C (SMBC),mineralizable C,and particulate organic matter C (POM-C) compared to conventional cropping systems.Soil C concentrations were in the order:long-term coastal bermudagrass [Cynodon dactylon (L.) Pers.] > switchgrass or kleingrass (Panicum coloratum L.) planted in 1992 > switchgrass 1997 > conventional cropping systems.Soil C concentrations tended to increase with increasing clay content.Greater microbial biomass C followed the order of Dallas >College Station > Stephenville,and ranged from approximately 180 mg C kg-1 soil at Stephenville to 1900 mg C kg-1 soil at Dallas.Particulate organic C was more sensitive than other fractions to management,increasing as much as 6-fold under long-term coastal bermudagrass compared to conventional cropping systems.Our study indicated that conversion of conventional cropping systems into switchgrass production can sequestrate more SOC and improve soil biological properties in the southern USA.

  17. Productivity and carbon footprint of perennial grass-forage legume intercropping strategies with high or low nitrogen fertilizer input.

    Science.gov (United States)

    Hauggaard-Nielsen, Henrik; Lachouani, Petra; Knudsen, Marie Trydeman; Ambus, Per; Boelt, Birte; Gislum, René

    2016-01-15

    A three-season field experiment was established and repeated twice with spring barley used as cover crop for different perennial grass-legume intercrops followed by a full year pasture cropping and winter wheat after sward incorporation. Two fertilization regimes were applied with plots fertilized with either a high or a low rate of mineral nitrogen (N) fertilizer. Life cycle assessment (LCA) was used to evaluate the carbon footprint (global warming potential) of the grassland management including measured nitrous oxide (N2O) emissions after sward incorporation. Without applying any mineral N fertilizer, the forage legume pure stand, especially red clover, was able to produce about 15 t above ground dry matter ha(-1) year(-1) saving around 325 kg mineral Nfertilizer ha(-1) compared to the cocksfoot and tall fescue grass treatments. The pure stand ryegrass yielded around 3t DM more than red clover in the high fertilizer treatment. Nitrous oxide emissions were highest in the treatments containing legumes. The LCA showed that the low input N systems had markedly lower carbon footprint values than crops from the high N input system with the pure stand legumes without N fertilization having the lowest carbon footprint. Thus, a reduction in N fertilizer application rates in the low input systems offsets increased N2O emissions after forage legume treatments compared to grass plots due to the N fertilizer production-related emissions. When including the subsequent wheat yield in the total aboveground production across the three-season rotation, the pure stand red clover without N application and pure stand ryegrass treatments with the highest N input equalled. The present study illustrate how leguminous biological nitrogen fixation (BNF) represents an important low impact renewable N source without reducing crop yields and thereby farmers earnings.

  18. Productivity and carbon footprint of perennial grass-forage legume intercropping strategies with high or low nitrogen fertilizer input.

    Science.gov (United States)

    Hauggaard-Nielsen, Henrik; Lachouani, Petra; Knudsen, Marie Trydeman; Ambus, Per; Boelt, Birte; Gislum, René

    2016-01-15

    A three-season field experiment was established and repeated twice with spring barley used as cover crop for different perennial grass-legume intercrops followed by a full year pasture cropping and winter wheat after sward incorporation. Two fertilization regimes were applied with plots fertilized with either a high or a low rate of mineral nitrogen (N) fertilizer. Life cycle assessment (LCA) was used to evaluate the carbon footprint (global warming potential) of the grassland management including measured nitrous oxide (N2O) emissions after sward incorporation. Without applying any mineral N fertilizer, the forage legume pure stand, especially red clover, was able to produce about 15 t above ground dry matter ha(-1) year(-1) saving around 325 kg mineral Nfertilizer ha(-1) compared to the cocksfoot and tall fescue grass treatments. The pure stand ryegrass yielded around 3t DM more than red clover in the high fertilizer treatment. Nitrous oxide emissions were highest in the treatments containing legumes. The LCA showed that the low input N systems had markedly lower carbon footprint values than crops from the high N input system with the pure stand legumes without N fertilization having the lowest carbon footprint. Thus, a reduction in N fertilizer application rates in the low input systems offsets increased N2O emissions after forage legume treatments compared to grass plots due to the N fertilizer production-related emissions. When including the subsequent wheat yield in the total aboveground production across the three-season rotation, the pure stand red clover without N application and pure stand ryegrass treatments with the highest N input equalled. The present study illustrate how leguminous biological nitrogen fixation (BNF) represents an important low impact renewable N source without reducing crop yields and thereby farmers earnings. PMID:26479907

  19. Lasting mantle scars lead to perennial plate tectonics.

    Science.gov (United States)

    Heron, Philip J; Pysklywec, Russell N; Stephenson, Randell

    2016-06-10

    Mid-ocean ridges, transform faults, subduction and continental collisions form the conventional theory of plate tectonics to explain non-rigid behaviour at plate boundaries. However, the theory does not explain directly the processes involved in intraplate deformation and seismicity. Recently, damage structures in the lithosphere have been linked to the origin of plate tectonics. Despite seismological imaging suggesting that inherited mantle lithosphere heterogeneities are ubiquitous, their plate tectonic role is rarely considered. Here we show that deep lithospheric anomalies can dominate shallow geological features in activating tectonics in plate interiors. In numerical experiments, we found that structures frozen into the mantle lithosphere through plate tectonic processes can behave as quasi-plate boundaries reactivated under far-field compressional forcing. Intraplate locations where proto-lithospheric plates have been scarred by earlier suturing could be regions where latent plate boundaries remain, and where plate tectonics processes are expressed as a 'perennial' phenomenon.

  20. Matrix population models from 20 studies of perennial plant populations

    Science.gov (United States)

    Ellis, Martha M.; Williams, Jennifer L.; Lesica, Peter; Bell, Timothy J.; Bierzychudek, Paulette; Bowles, Marlin; Crone, Elizabeth E.; Doak, Daniel F.; Ehrlen, Johan; Ellis-Adam, Albertine; McEachern, Kathryn; Ganesan, Rengaian; Latham, Penelope; Luijten, Sheila; Kaye, Thomas N.; Knight, Tiffany M.; Menges, Eric S.; Morris, William F.; den Nijs, Hans; Oostermeijer, Gerard; Quintana-Ascencio, Pedro F.; Shelly, J. Stephen; Stanley, Amanda; Thorpe, Andrea; Tamara, Ticktin; Valverde, Teresa; Weekley, Carl W.

    2012-01-01

    Demographic transition matrices are one of the most commonly applied population models for both basic and applied ecological research. The relatively simple framework of these models and simple, easily interpretable summary statistics they produce have prompted the wide use of these models across an exceptionally broad range of taxa. Here, we provide annual transition matrices and observed stage structures/population sizes for 20 perennial plant species which have been the focal species for long-term demographic monitoring. These data were assembled as part of the 'Testing Matrix Models' working group through the National Center for Ecological Analysis and Synthesis (NCEAS). In sum, these data represent 82 populations with >460 total population-years of data. It is our hope that making these data available will help promote and improve our ability to monitor and understand plant population dynamics.

  1. Matrix population models from 20 studies of perennial plant populations

    Science.gov (United States)

    Ellis, Martha M.; Williams, Jennifer L.; Lesica, Peter; Bell, Timothy J.; Bierzychudek, Paulette; Bowles, Marlin; Crone, Elizabeth E.; Doak, Daniel F.; Ehrlen, Johan; Ellis-Adam, Albertine; McEachern, Kathryn; Ganesan, Rengaian; Latham, Penelope; Luijten, Sheila; Kaye, Thomas N.; Knight, Tiffany M.; Menges, Eric S.; Morris, William F.; den Nijs, Hans; Oostermeijer, Gerard; Quintana-Ascencio, Pedro F.; Shelly, J. Stephen; Stanley, Amanda; Thorpe, Andrea; Tamara, Ticktin; Valverde, Teresa; Weekley, Carl W.

    2012-01-01

    Demographic transition matrices are one of the most commonly applied population models for both basic and applied ecological research. The relatively simple framework of these models and simple, easily interpretable summary statistics they produce have prompted the wide use of these models across an exceptionally broad range of taxa. Here, we provide annual transition matrices and observed stage structures/population sizes for 20 perennial plant species which have been the focal species for long-term demographic monitoring. These data were assembled as part of the "Testing Matrix Models" working group through the National Center for Ecological Analysis and Synthesis (NCEAS). In sum, these data represent 82 populations with >460 total population-years of data. It is our hope that making these data available will help promote and improve our ability to monitor and understand plant population dynamics.

  2. Lasting mantle scars lead to perennial plate tectonics

    Science.gov (United States)

    Heron, Philip J.; Pysklywec, Russell N.; Stephenson, Randell

    2016-06-01

    Mid-ocean ridges, transform faults, subduction and continental collisions form the conventional theory of plate tectonics to explain non-rigid behaviour at plate boundaries. However, the theory does not explain directly the processes involved in intraplate deformation and seismicity. Recently, damage structures in the lithosphere have been linked to the origin of plate tectonics. Despite seismological imaging suggesting that inherited mantle lithosphere heterogeneities are ubiquitous, their plate tectonic role is rarely considered. Here we show that deep lithospheric anomalies can dominate shallow geological features in activating tectonics in plate interiors. In numerical experiments, we found that structures frozen into the mantle lithosphere through plate tectonic processes can behave as quasi-plate boundaries reactivated under far-field compressional forcing. Intraplate locations where proto-lithospheric plates have been scarred by earlier suturing could be regions where latent plate boundaries remain, and where plate tectonics processes are expressed as a `perennial' phenomenon.

  3. Lasting mantle scars lead to perennial plate tectonics.

    Science.gov (United States)

    Heron, Philip J; Pysklywec, Russell N; Stephenson, Randell

    2016-01-01

    Mid-ocean ridges, transform faults, subduction and continental collisions form the conventional theory of plate tectonics to explain non-rigid behaviour at plate boundaries. However, the theory does not explain directly the processes involved in intraplate deformation and seismicity. Recently, damage structures in the lithosphere have been linked to the origin of plate tectonics. Despite seismological imaging suggesting that inherited mantle lithosphere heterogeneities are ubiquitous, their plate tectonic role is rarely considered. Here we show that deep lithospheric anomalies can dominate shallow geological features in activating tectonics in plate interiors. In numerical experiments, we found that structures frozen into the mantle lithosphere through plate tectonic processes can behave as quasi-plate boundaries reactivated under far-field compressional forcing. Intraplate locations where proto-lithospheric plates have been scarred by earlier suturing could be regions where latent plate boundaries remain, and where plate tectonics processes are expressed as a 'perennial' phenomenon. PMID:27282541

  4. Establishing the basis for Genomic Prediction in Perennial Ryegrass

    DEFF Research Database (Denmark)

    Fé, Dario

    2015-01-01

    Genomic Selection (GS) is a relatively new technology, which has already revolutionized animal breeding and which is expected to have a high impact on plant breeding. In contrast to traditional marker assisted breeding, which only focuses on specific genes. GS estimates the genetic value...... of individuals/families by using genomic information over the Whole genome. The benefits of GS include reductions in expensive and time-consuming phenotyping operations, higher genetic gains, and simultaneous selection of multiple traits. To date, GS has primarely been tested in species, which are grown...... ryegrass (Lolium perenne L.), which is the most cultivated forage grass in temperate regions. Different statistical models were used for predicting the phenotypes of perennial ryegrass families, across diffent environments. Results showed good prospects for GS implementation in forage breeding, due...

  5. Evaluating environmental consequences of producing herbaceous crops for bioenergy

    International Nuclear Information System (INIS)

    The environmental costs and benefits of producing bioenergy crops can be measured both in kterms of the relative effects on soil, water, and wildlife habitat quality of replacing alternate cropping systems with the designated bioenergy system, and in terms of the quality and amount of energy that is produced per unit of energy expended. While many forms of herbaceous and woody energy crops will likely contribute to future biofuels systems, The Dept. of Energy's Biofuels Feedstock Development Program (BFDP), has chosen to focus its primary herbaceous crops research emphasis on a perennial grass species, switchgrass (Panicum virgatum), as a bioenergy candidate. This choice was based on its high yields, high nutrient use efficiency, and wide geographic distribution, and also on its poistive environmental attributes. The latter include its positive effects on soil quality and stabiity, its cover value for wildlife, and the lower inputs of enerty, water, and agrochemicals required per unit of energy produced. A comparison of the energy budgets for corn, which is the primary current source of bioethanol, and switchgrass reveals that the efficiency of energy production for a perennial grass system can exceed that for an energy intensive annual row crop by as much as 15 times. In additions reductions in CO2 emission, tied to the energetic efficiency of producing transportation fuels, are very efficient with grasses. Calculated carbon sequestration rates may exceed those of annual crops by as much as 20--30 times, due in part to carbon storage in the soil. These differences have major implications for both the rate and efficiency with which fossil energy sources can be replaced with cleaner burning biofuels

  6. Perennial plate tectonics with lasting mantle lithosphere scars

    Science.gov (United States)

    Heron, P.; Pysklywec, R. N.; Stephenson, R.

    2015-12-01

    Although the conventional theory of plate tectonics can explain non-rigid behaviour at plate boundaries, it cannot adequately explain the processes involved in deformation and seismicity within plate interiors. Here, we consider that the pre-existing deformation or "scarring" within the mantle lithosphere may have a very long lived presence that could incorporate deformation of the plate interior and plate boundary. Mantle lithosphere scars from continent-continent collisions could generate virtual plate boundaries that remain over long timescales, producing "perennial" plate tectonics. Local geophysical studies can map the crustal environment well, and global whole mantle tomography models are rapidly improving, yet high-resolution images of the mantle lithosphere are often not available in regions where scarring may be present. Where mantle lithosphere heterogeneities have been observed (usually interpreted simply as subduction scars), the same attention has not been afforded to them as, for example, re-activation of faults within the Earth's crust. In idealized numerical simulations, we compare how relic scarring at varying depths in the lithosphere affects patterns of deformation. High-resolution thermal-mechanical numerical experiments explore continental lithospheric deformation featuring a weakened crust and mantle lithosphere scars. Our models show that deep lithospheric scars can control the tectonic evolution of a region over shallow geological features, indicating the importance of mantle lithosphere heterogeneities. The Altyn Tagh Fault (ATF) in central China is an example of an ancient continental collision zone that undergoes periodic deformation during times of regional compression. We suggest that the ATF may be a locale where a long-lasting mantle lithosphere scar can control the subsequent crustal evolution and deformation, with ancient plate boundaries having a "perennial" plate tectonic presence.

  7. Biomass Partitioning Following Defoliation of Annual and Perennial Mediterranean Grasses

    Directory of Open Access Journals (Sweden)

    No'am Seligman

    2002-01-01

    Full Text Available A two-year experiment was conducted in northeastern Israel to study the effects of various defoliation regimes on biomass partitioning between vegetative and reproductive structures in a perennial and an annual Mediterranean grass. Greater insight into the mechanisms regulating biomass partitioning after defoliation enables ecologists and rangeland managers to interpret and predict population and community dynamics in Mediterranean grasslands more efficiently. Two typical Mediterranean grasses, Triticum dicoccoides, an annual species, and Hordeum bulbosum, a perennial species, were grown in containers in the open. They were subjected to a series of defoliation treatments that comprised three clipping frequencies and three clipping heights in a full factorial combination. In addition, individuals of both species were sampled in the field, in paddocks that were grazed, and in a control exclosure that was closed to grazing during the growing season. The experiment was conducted over two growing seasons, one unusually dry and one unusually wet. The clipping treatments invariably caused a reduction in the amount of biomass partitioned to the reproductive organs, but had little effect on the vegetative components of the plants. Greater tillering following defoliation compensated, to a large degree, for the loss of photosynthetic biomass following defoliation. The effect of grazing on biomass partitioning was much lower than the effect of clipping. Under grazing, the investment in reproductive biomass was considerably higher than when the grasses were clipped. The results of this experiment help to elucidate the reasons for the persistence of these species and, especially, for the dominance of Hordeum bulbosum in many eastern Mediterranean grasslands.

  8. [Biofuels, food security and transgenic crops].

    Science.gov (United States)

    Acosta, Orlando; Chaparro-Giraldo, Alejandro

    2009-01-01

    Soaring global food prices are threatening to push more poor people back below the poverty line; this will probably become aggravated by the serious challenge that increasing population and climate changes are posing for food security. There is growing evidence that human activities involving fossil fuel consumption and land use are contributing to greenhouse gas emissions and consequently changing the climate worldwide. The finite nature of fossil fuel reserves is causing concern about energy security and there is a growing interest in the use of renewable energy sources such as biofuels. There is growing concern regarding the fact that biofuels are currently produced from food crops, thereby leading to an undesirable competition for their use as food and feed. Nevertheless, biofuels can be produced from other feedstocks such as lingo-cellulose from perennial grasses, forestry and vegetable waste. Biofuel energy content should not be exceeded by that of the fossil fuel invested in its production to ensure that it is energetically sustainable; however, biofuels must also be economically competitive and environmentally acceptable. Climate change and biofuels are challenging FAO efforts aimed at eradicating hunger worldwide by the next decade. Given that current crops used in biofuel production have not been domesticated for this purpose, transgenic technology can offer an enormous contribution towards improving biofuel crops' environmental and economic performance. The present paper critically presents some relevant relationships between biofuels, food security and transgenic plant technology.

  9. ERTS-1 applications to California resource inventory

    Science.gov (United States)

    Colwell, R. N. (Principal Investigator)

    1972-01-01

    There are no author-identified significant results in this report. ERTS-1 information will be utilized by resource management groups working in the fields of forestry, hydrology, range management, and agriculture to develop resource inventories of the state of California. Five examples are given of the use of ERTS-1 imagery and aerial photography in identifying different crops and field conditions.

  10. Biogas from ley crops

    International Nuclear Information System (INIS)

    This report describes the cost of producing biogas from energy crops. Five process systems, sized 0.25-8 MW are studied. The cultivation of biogas-crops is made in three regions in Sweden. Also valued are the positive cultivation effects obtained when cereal dominated crop rotation is broken by biogas crops. 8 refs, 40 figs, 10 tabs

  11. Energy crops for biogas

    International Nuclear Information System (INIS)

    This investigation aims at describing the effects on cropping systems, containing a.o. leguminosae plant leys for biogas production. Problems treated are effects on soil physics, circulation of crop nutrients, use of chemical pesticides, preceding crop effects, and the possibility of utilizing catch crops for methane production. It is observed that the studied biogas-crop sequences gives positive effects on soil structure, reduced need for artificial fertilizers and chemical pesticides. 26 refs, 28 tabs

  12. Multiple Peril Crop Insurance

    OpenAIRE

    Edwards, William M.; Hofstrand, Donald

    2003-01-01

    Multiple Peril Crop Insurance (MPCI) is a broad-based crop insurance program regulated by the U.S. Department of Agriculture and subsidized by the Federal Crop Insurance Corporation(FCIC). Crops eligible for MPCI coverage in Iowa include corn, sobyeans, oats, wheat, seed corn, popcorn, barley, potatoes, sweet corn, canning beans, dry beans, forages, grain sorghum, green peas, tomatoes, and nursery stocks. Not all of these crops can be insured in all counties.

  13. Short Rotation Crops in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Wright, L L

    1998-06-04

    The report is based primarily on the results of survey questions sent to approximately 60 woody and 20 herbaceous crop researchers in the United States and on information from the U.S. Department of Energy's Bioenergy Feedstock Development Program. Responses were received from 13 individuals involved in woody crops research or industrial commercialization (with 5 of the responses coming from industry). Responses were received from 11 individuals involved in herbaceous crop research. Opinions on market incentives, technical and non-technical barriers, and highest priority research and development areas are summarized in the text. Details on research activities of the survey responders are provided as appendices to the paper. Woody crops grown as single-stem systems (primarily Populus and Eucalyptus species) are perceived to have strong pulp fiber and oriented strand board markets, and the survey responders anticipated that energy will comprise 25% or less of the utilization of single-stem short-rotation woody crops between now and 2010. The only exception was a response from California where a substantial biomass energy market does currently exist. Willows (Salix species) are only being developed for energy and only in one part of the United States at present. Responses from herbaceous crop researchers suggested frustration that markets (including biomass energy markets) do not currently exist for the crop, and it was the perception of many that federal incentives will be needed to create such markets. In all crops, responses indicate that a wide variety of research and development activities are needed to enhance the yields and profitability of the crops. Ongoing research activities funded by the U.S. Department of Energy's Bioenergy Feedstock Development Program are described in an appendix to the paper.

  14. Transcriptome Analysis in Sheepgrass (Leymus chinensis). A Dominant Perennial Grass of the Eurasian Steppe

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Shuangyan [Chinese Academy of Sciences (CAS), Institute of Botany (IB), Beijing; Huang, Xin [Chinese Academy of Sciences (CAS), Institute of Botany (IB), Beijing; Yang, Xiaohan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Liu, Gongshe [Chinese Academy of Sciences (CAS), Institute of Botany (IB), Beijing

    2013-07-04

    BACKGROUND: Sheepgrass [Leymus chinensis (Trin.) Tzvel.] is an important perennial forage grass across the Eurasian Steppe and is known for its adaptability to various environmental conditions. However, insufficient data resources in public databases for sheepgrass limited our understanding of the mechanism of environmental adaptations, gene discovery and molecular marker development. RESULTS: The transcriptome of sheepgrass was sequenced using Roche 454 pyrosequencing technology. We assembled 952,328 high-quality reads into 87,214 unigenes, including 32,416 contigs and 54,798 singletons. There were 15,450 contigs over 500 bp in length. BLAST searches of our database against Swiss-Prot and NCBI non-redundant protein sequences (nr) databases resulted in the annotation of 54,584 (62.6%) of the unigenes. Gene Ontology (GO) analysis assigned 89,129 GO term annotations for 17,463 unigenes. We identified 11,675 core Poaceae-specific and 12,811 putative sheepgrass-specific unigenes by BLAST searches against all plant genome and transcriptome databases. A total of 2,979 specific freezing-responsive unigenes were found from this RNAseq dataset. We identified 3,818 EST-SSRs in 3,597 unigenes, and some SSRs contained unigenes that were also candidates for freezing-response genes. Characterizations of nucleotide repeats and dominant motifs of SSRs in sheepgrass were also performed. Similarity and phylogenetic analysis indicated that sheepgrass is closely related to barley and wheat. CONCLUSIONS: This research has greatly enriched sheepgrass transcriptome resources. The identified stress-related genes will help us to decipher the genetic basis of the environmental and ecological adaptations of this species and will be used to improve wheat and barley crops through hybridization or genetic transformation. The EST-SSRs reported here will be a valuable resource for future gene-phenotype studies and for the molecular breeding of sheepgrass and other Poaceae species.

  15. Transcriptome analysis in sheepgrass (Leymus chinensis: a dominant perennial grass of the Eurasian Steppe.

    Directory of Open Access Journals (Sweden)

    Shuangyan Chen

    Full Text Available BACKGROUND: Sheepgrass [Leymus chinensis (Trin. Tzvel.] is an important perennial forage grass across the Eurasian Steppe and is known for its adaptability to various environmental conditions. However, insufficient data resources in public databases for sheepgrass limited our understanding of the mechanism of environmental adaptations, gene discovery and molecular marker development. RESULTS: The transcriptome of sheepgrass was sequenced using Roche 454 pyrosequencing technology. We assembled 952,328 high-quality reads into 87,214 unigenes, including 32,416 contigs and 54,798 singletons. There were 15,450 contigs over 500 bp in length. BLAST searches of our database against Swiss-Prot and NCBI non-redundant protein sequences (nr databases resulted in the annotation of 54,584 (62.6% of the unigenes. Gene Ontology (GO analysis assigned 89,129 GO term annotations for 17,463 unigenes. We identified 11,675 core Poaceae-specific and 12,811 putative sheepgrass-specific unigenes by BLAST searches against all plant genome and transcriptome databases. A total of 2,979 specific freezing-responsive unigenes were found from this RNAseq dataset. We identified 3,818 EST-SSRs in 3,597 unigenes, and some SSRs contained unigenes that were also candidates for freezing-response genes. Characterizations of nucleotide repeats and dominant motifs of SSRs in sheepgrass were also performed. Similarity and phylogenetic analysis indicated that sheepgrass is closely related to barley and wheat. CONCLUSIONS: This research has greatly enriched sheepgrass transcriptome resources. The identified stress-related genes will help us to decipher the genetic basis of the environmental and ecological adaptations of this species and will be used to improve wheat and barley crops through hybridization or genetic transformation. The EST-SSRs reported here will be a valuable resource for future gene-phenotype studies and for the molecular breeding of sheepgrass and other Poaceae species.

  16. Enhanced Yields in Organic Arable Crop Production by Eco-Functional Intensification using Intercropping

    DEFF Research Database (Denmark)

    Jensen, Erik Steen; Bedoussac, Laurent; Carlsson, Georg;

    2015-01-01

    Organic agriculture (OA) faces challenges to enhance food production per unit area and simultaneously reduce the environmental and climate impacts, e.g. nitrate leaching per unit land and green-houses gases (GHG) emissions per kg product. Eco-functional intensification (EFI) is suggested as a means...... by planned crop diversification in time (crop rotation). However, cultivating genetically identical plants in OA sole crops (SC), limits resource use efficiency and yield per unit area. Intercropping (IC) of annual species or cultivars, perennial polycultures of forage or grain crops and agroforestry...... are examples of spatial crop diversification, which based on eco-functional intensification may enhance yield by the interspecies competitive production principle, only partly niche overlap and complementarity in resource use in time and space. Intercropping of species is based on the ecological principles...

  17. Effects of catch crop type and root depth on nitrogen leaching and yield of spring barley

    DEFF Research Database (Denmark)

    Sapkota, Tek Bahadur; Askegaard, Margrethe; Lægdsmand, Mette;

    2012-01-01

    [chicory (Cichorium intybus L.), fodder radish (Raphanus sativus L.) and perennial ryegrass (Lolium perenne L.)] and their effect on soil mineral N (NO3− and NH4+) in different soil layers by using the FASSET model. The simulated results of catch crop biomass and root growth and mineral N in the soil...... simulations showed that fodder radish developed the deepest root system and depleted N from deeper soil layers than chicory and ryegrass. Thirty years of simulations showed that the system with ryegrass catch crop had a smaller amount of N leaching from 1 m depth than the system with other catch crops and...... without catch crops. However, estimated total N leached at 2 m soil depth was smallest in the system with fodder radish followed by the system with chicory, indicating that these catch crops are capable of taking soil N also from below 1 m depth. On average, the system with fodder radish was estimated to...

  18. Biogas production from energy crops and agriculture residues

    Energy Technology Data Exchange (ETDEWEB)

    Wang, G.

    2010-12-15

    In this thesis, the feasibility of utilizing energy crops (willow and miscanthus) and agriculture residues (wheat straw and corn stalker) in an anaerobic digestion process for biogas production was evaluated. Potential energy crops and agriculture residues were screened according to their suitability for biogas production. Moreover, pretreatment of these biomasses by using wet explosion method was studied and the effect of the wet explosion process was evaluated based on the increase of (a) sugar release and (b) methane potential when comparing the pretreated biomass and raw biomass. Ensiling of perennial crops was tested as a storage method and pretreatment method for enhancement of the biodegradability of the crops. The efficiency of the silage process was evaluated based on (a) the amount of biomass loss during storage and (b) the effect of the silage on methane potential. Co-digestion of raw and wet explosion pretreated energy crops and agriculture residues with swine manure at various volatile solids (VS) ratio between crop and manure was carried out by batch tests and continuous experiments. The efficiency of the co-digestion experiment was evaluated based on (a) the methane potential in term of ml CH4 produced per g of VS-added and (b) the amount of methane produced per m3 of reactor volume. (Author)

  19. Similarity of climate control on base flow and perennial stream density in the Budyko framework

    Directory of Open Access Journals (Sweden)

    D. Wang

    2013-01-01

    Full Text Available Connection between perennial stream and base flow at the mean annual scale exists since one of the hydrologic functions of perennial stream is to deliver runoff even in low flow seasons. The partitioning of precipitation into runoff and evaporation at the mean annual scale, on the first order, is captured by the ratio of potential evaporation to precipitation (EP/P called climate aridity index based on Budyko hypothesis. Perennial stream density (DP, which is obtained from the high resolution National Hydrography Dataset, for 185 watersheds declines monotonically with climate aridity index, and an inversely proportional function is proposed to model the relationship between DP and EP/P. The monotonic trend of perennial stream density reconciles with the Abrahams curve since perennial stream density is only a small portion of the total drainage density. The correlation coefficient between the ratio of base flow to precipitation (Qb/P, which follows a complementary Budyko type curve and perennial stream density is found to be 0.74. The similarity between Qb/P and DP reveals the co-evolution between water balance and perennial stream network.

  20. Perennial filter strips reduce nitrate levels in soil and shallow groundwater after grassland-to-cropland conversion.

    Science.gov (United States)

    Zhou, Xiaobo; Helmers, Matthew J; Asbjornsen, Heidi; Kolka, Randy; Tomer, Mark D

    2010-01-01

    Many croplands planted to perennial grasses under the Conservation Reserve Program are being returned to crop production, and with potential consequences for water quality. The objective of this study was to quantify the impact of grassland-to-cropland conversion on nitrate-nitrogen (NO3-N) concentrations in soil and shallow groundwater and to assess the potential for perennial filter strips (PFS) to mitigate increases in NO3-N levels. The study, conducted at the Neal Smith National Wildlife Refuge (NSNWR) in central Iowa, consisted of a balanced incomplete block design with 12 watersheds and four watershed-scale treatments having different proportions and topographic positions of PFS planted in native prairie grasses: 100% rowcrop, 10% PFS (toeslope position), 10% PFS (distributed on toe and as contour strips), and 20 PFS (distributed on toe and as contour strips). All treatments were established in fall 2006 on watersheds that were under bromegrass (Bromus L.) cover for at least 10 yr. Nonperennial areas were maintained under a no-till 2-yr corn (Zea mays L.)--soybean [Glycine max. (L.) Merr.] rotation since spring 2007. Suction lysimeter and shallow groundwater wells located at upslope and toeslope positions were sampled monthly during the growing season to determine NO3-N concentration from 2005 to 2008. The results indicated significant increases in NO3-N concentration in soil and groundwater following grassland-to-cropland conversion. Nitrate-nitrogen levels in the vadose zone and groundwater under PFS were lower compared with 100% cropland, with the most significant differences occurring at the toeslope position. During the years following conversion, PFS mitigated increases in subsurface nitrate, but long-term monitoring is needed to observe and understand the full response to land-use conversion.

  1. Prediction models of silage fermentation products on crop composition under strict anaerobic conditions: a meta-analysis.

    Science.gov (United States)

    Mogodiniyai Kasmaei, K; Rustas, B-O; Spörndly, R; Udén, P

    2013-10-01

    A meta-analysis was conducted to establish linkages between crop and fermentation variables. Data from well-controlled mini silage studies were used in which no additives had been used and no ingress of air had occurred. The silage set consisted of data on crop chemical composition and epiphytic lactic acid bacteria count, and fermentation products (organic acids, alcohols, and ammonia-N) from 118 silages made from 30 grass, 7 legume, 15 grass and legume mixtures, and 66 whole-crop maize samples. The prediction models for fermentation products on crop variables were obtained by stepwise multiple regression analysis. Perennial forage and maize silages were analyzed separately. The best models were obtained for acetic acid in perennial forage silages, with a coefficient of determination of 0.63, and for lactic acid and ethanol in whole-crop maize silages, with coefficients of determination of 0.84 and 0.61, respectively. Fermentation products of perennial forage and maize silages were best related to dry matter and crude protein contents, respectively. Overall, the prediction equations were weak.

  2. Summary appraisals of the Nation's ground-water resources; California region

    Science.gov (United States)

    Thomas, H.E.; Phoenix, D.A.

    1976-01-01

    Most people in the California Region live in a semiarid or arid climate, with precipitation less than the potential evapotranspiration- environments of perennial water deficiency. The deficiency becomes most onerous during the characteristically rainless summers and during recurrent droughts that may continue for 10--20 years. However, water from winter rain and snow can be stored for use during the dry summer months, and water stored during a wet climatic period can be used in a succeeding dry period; moreover, perennial deficiency can be overcome by bringing water from areas of perennial surplus. Ground-water reservoirs have especial significance in arid and semiarid regions as repositories where water is stored or can be stored with minimum loss by evaporation.

  3. Ecosystem Change in California Grasslands: Impacts of Species Invasion

    Science.gov (United States)

    Koteen, L. E.; Harte, J.; Baldocchi, D. D.

    2009-12-01

    Grassland ecosystems of California have undergone dramatic changes, resulting in the almost complete replacement of native perennial grasses by non-native annuals across millions of hectares of grassland habitat. Our research investigates the effects of this community shift on carbon, water and energy cycles at two sites in northern coastal California. Our goal was to understand how changes to California’s grasslands have affected climate through 1. shifting the balance of carbon storage between terrestrial stocks and the atmosphere, and 2. altering the water and energy regimes that heat or cool the earth's surface. To compare the processes that govern material exchange before and after annual grass invasion, we made use of sites where native vegetation is found adjacent to locations that have undergone non-native invasion. In plots of each vegetation type, we monitored whole plant productivity, root and litter decay rates and soil respiration, as well as soil climatic controls on these processes. At one site, we also measured surface albedo and the components of the surface energy balance in each grass community, using the surface renewal method. Although seemingly subtle, the shift in California grassland communities from native perennial to non-native annual grass dominance has had profound consequences for ecosystem biogeochemical, radiative and hydrological cycles. Soil carbon storage was found to be significantly greater in native perennial grass communities. Across both study sites, we found that non-native grass invasion has resulted in the transfer of from 3 to 6 tons of carbon per hectare from the soil to the atmosphere, dependent on site and species. A soil density fractionation and a radiocarbon analysis also revealed the carbon to be more recalcitrant in native grass dominated locations. The primary plant traits that help explain why soil carbon losses follow annual grass invasion are: 1. differences between annual and perennial grasses in above

  4. California Simulation of Evapotranspiration of Applied Water and Agricultural Energy Use in California

    Institute of Scientific and Technical Information of China (English)

    Morteza N Orang; Richard L Snyder; Shu Geng; Quinn J Hart; Sara Sarreshteh; Matthias Falk; Dylan Beaudette; Scott Hayes; Simon Eching

    2013-01-01

    The California Simulation of Evapotranspiration of Applied Water (Cal-SIMETAW) model is a new tool developed by the California Department of Water Resources and the University of California, Davis to perform daily soil water balance and determine crop evapotranspiration (ETc), evapotranspiration of applied water (ETaw), and applied water (AW) for use in California water resources planning. ETaw is a seasonal estimate of the water needed to irrigate a crop assuming 100%irrigation efficiency. The model accounts for soils, crop coefficients, rooting depths, seepage, etc. that influence crop water balance. It provides spatial soil and climate information and it uses historical crop and land-use category information to provide seasonal water balance estimates by combinations of detailed analysis unit and county (DAU/County) over California. The result is a large data base of ETc and ETaw that will be used to update information in the new California Water Plan (CWP). The application uses the daily climate data, i.e., maximum (Tx) and minimum (Tn) temperature and precipitation (Pcp), which were derived from monthly USDA-NRCS PRISM data (PRISM Group 2011) and daily US National Climate Data Center (NCDC) climate station data to cover California on a 4 km×4 km change grid spacing. The application uses daily weather data to determine reference evapotranspiration (ETo), using the Hargreaves-Samani (HS) equation (Hargreaves and Samani 1982, 1985). Because the HS equation is based on temperature only, ETo from the HS equation were compared with CIMIS ETo at the same locations using available CIMIS data to determine correction factors to estimate CIMIS ETo from the HS ETo to account for spatial climate differences. Cal-SIMETAW also employs near real-time reference evapotranspiration (ETo) information from Spatial CIMIS, which is a model that combines weather station data and remote sensing to provide a grid of ETo information. A second database containing the available soil

  5. Developing Switchgrass as a Bioenergy Crop

    Energy Technology Data Exchange (ETDEWEB)

    Bouton, J.; Bransby, D.; Conger, B.; McLaughlin, S.; Ocumpaugh, W.; Parrish, D.; Taliaferro, C.; Vogel, K.; Wullschleger, S.

    1998-11-08

    The utilization of energy crops produced on American farms as a source of renewable fuels is a concept with great relevance to current ecological and economic issues at both national and global scales. Development of a significant national capacity to utilize perennial forage crops, such as switchgrass (Panicum virgatum, L.) as biofuels could benefit our agricultural economy by providing an important new source of income for farmers. In addition energy production from perennial cropping systems, which are compatible with conventional fining practices, would help reduce degradation of agricultural soils, lower national dependence on foreign oil supplies, and reduce emissions of greenhouse gases and toxic pollutants to the atmosphere (McLaughlin 1998). Interestingly, on-farm energy production is a very old concept, extending back to 19th century America when both transpofiation and work on the farm were powered by approximately 27 million draft animals and fueled by 34 million hectares of grasslands (Vogel 1996). Today a new form of energy production is envisioned for some of this same acreage. The method of energy production is exactly the same - solar energy captured in photosynthesis, but the subsequent modes of energy conversion are vastly different, leading to the production of electricity, transportation fuels, and chemicals from the renewable feedstocks. While energy prices in the United States are among the cheapest in the world, the issues of high dependency on imported oil, the uncertainties of maintaining stable supplies of imported oil from finite reserves, and the environmental costs associated with mining, processing, and combusting fossil fuels have been important drivers in the search for cleaner burning fuels that can be produced and renewed from the landscape. At present biomass and bioenergy combine provide only about 4% of the total primary energy used in the U.S. (Overend 1997). By contrast, imported oil accounts for approximately 44% of the

  6. PREDICTING THE IMPACT OF NEW CROPPING PRACTICES UPON SUBSISTENCE FARMING: A FARM LEVEL ANALYSIS IN BRAZIL

    OpenAIRE

    Brandao, Elizabeth Santos; McCarl, Bruce A.; Schuh, G. Edward

    1984-01-01

    An analysis is done on the potential effects of several improved cropping practices in a subsistence agricultural farming system along with analyses of other development options. The farming system is modeled as a linear programming model. The problem involves mixture of perennials and annuals, sharecropping provisions and risk. The practices are found to have differential effects on the distribution of income between the landlords and tenants, marketable surplus and on farm employment.

  7. BETA DIVERSITY AND COMMUNITY DIFFERENTIATION IN DRY PERENNIAL SAND GRASSLANDS

    Directory of Open Access Journals (Sweden)

    E. KOVACS-LANG

    2011-01-01

    Full Text Available The spatial variability of species composition was studied in perennial sand grasslands in Hungary at multiple scales. Three sites were compared along an aridity gradient. Existing differences in climate along this ca. 200 km gradient correspond to regional climate changes predicted for the next 20-30 years. Six stands of Festucetum vaginatae grasslands were selected at each site within 400 x 1200 m areas for representing the coarse-scale within-site heterogeneity. Fine-scale compositional heterogeneity of vegetation within stands was sampled by recording the presence of species along 52 m long circular belt transects of 1040 units of 5 cm x 5 cm contiguous microquadrats. This sampling design enabled us to study the patterns of species combinations at a wide range of scales. The highest variability of plant species combinations appeared at very fine scales, between 10 cm and 25 cm. Differences in beta diversity along the gradient were scale-dependent. We found a decreasing trend of beta diversity with increasing aridity at fine scale, and on the contrary, an increasing trend at landscape scale. We conclude that the major trend of the vegetation differentiation due to aridity is the decrease of compositional variability at fine-scale accompanied by a coarse-scale diversification.

  8. Root proliferation in native perennial grasses of arid Patagonia, Argentina

    Institute of Scientific and Technical Information of China (English)

    Yanina A. TORRES; Mara M. MUJICA; Sandra S. BAIONI; Jos ENTO; Mara N. FIORETTI; Guillermo TUCAT; Carlos A. BUSSO; Oscar A. MONTENEGRO; Leticia ITHURRART; Hugo D. GIORGETTI; Gustavo RODRGUEZ; Diego BENTIVEGNA; Roberto E. BREVEDAN; Osvaldo A. FERNNDEZ

    2014-01-01

    Pappophorum vaginatum is the most abundant C4 perennial grass desirable to livestock in rangelands of northeastern Patagonia, Argentina. We hypothesized that (1) defoliation reduce net primary productivity, and root length density and weight in the native species, and (2) root net primary productivity, and root length density and weight, are greater in P. vaginatum than in the other, less desirable, native species (i.e., Aristida spegazzinii, A. subulata and Sporobolus cryptandrus). Plants of all species were either exposed or not to a severe defoliation twice a year during two growing seasons. Root proliferation was measured using the cylinder method. Cylindrical, iron structures, wrapped up using nylon mesh, were buried diagonally from the periphery to the center on individual plants. These structures, initially filled with soil without any organic residue, were dug up from the soil on 25 April 2008, after two successive defoliations in mid-spring 2007. During the second growing season (2008-2009), cylinders were destructively harvested on 4 April 2009, after one or two defoliations in mid-and/or late-spring, respectively. Roots grown into the cylinders were obtained after washing the soil manually. Defoliation during two successive years did reduce the study variables only after plants of all species were defoliated twice, which supported the first hypothesis. The greater root net primary productivity, root length den-sity and weight in P. vaginatum than in the other native species, in support of the second hypothesis, could help to explain its greater abundance in rangelands of Argentina.

  9. Rainfed intensive crop systems

    DEFF Research Database (Denmark)

    Olesen, Jørgen E

    2014-01-01

    This chapter focuses on the importance of intensive cropping systems in contributing to the world supply of food and feed. The impact of climate change on intensive crop production systems is also discussed.......This chapter focuses on the importance of intensive cropping systems in contributing to the world supply of food and feed. The impact of climate change on intensive crop production systems is also discussed....

  10. On the mystery of the perennial carbon dioxide cap at the south pole of Mars

    OpenAIRE

    Guo, Xin; Richardson, Mark Ian; Soto, Alejandro; Toigo, Anthony

    2010-01-01

    A perennial ice cap has long been observed near the south pole of Mars. The surface of this cap is predominantly composed of carbon dioxide ice. The retention of a CO_2 ice cap results from the surface energy balance of the latent heat, solar radiation, surface emission, subsurface conduction, and atmospheric sensible heat. While models conventionally treat surface CO_2 ice using constant ice albedos and emissivities, such an approach fails to predict the existence of a perennial cap. Here we...

  11. Producing bulbs and perennials : sustainable control of diseases, pests and weeds

    OpenAIRE

    Boer

    2011-01-01

    In the Netherlands every year flower bulbs and perennials are produced representing a value of € 500 m (flower bulbs) and of € 65 m (perennials, 2004). The growers are faced with several threatening pests and diseases during the production. They usually deal with these problems by using pesticides. In 2004 the Ministry of Agriculture and the stakeholders in Agribusiness made an agreement on reducing the environmental impact of pesticides by developing and implementing knowledge on Integrated ...

  12. Dry matter production of perennial pasture Tifton 85 (Cynodon spp) under different doses of fertilization

    OpenAIRE

    Karlize Prigol; Patric André Castro; Débora Ferreira Laureano; Diego Chiodelli; Raquel Cristina Roman; Lenilson da Fonseca Roza; Luan Carlos Pagani; Edir Oliveira da Fonseca

    2012-01-01

    Dairy farming is an activity that provides the small rural farmer the opportunity to earn income in small areas of land. The perennial pastures represent a source for a cheap and nutritious diet for the animals. The correct management of perennial pastures can be the key to sustainability in the dairy business, resulting in the preservation or recovery of the balance of a pasture system, starting with the pursuit of production with low costs and good pasture production per unit area. The corr...

  13. Diversity of cultured bacteria from the perennial ice block of Scarisoara Ice Cave, Romania

    OpenAIRE

    Corina Iţcuş; Mădălina-Denisa Pascu; Traian Brad; Aurel Perşoiu; Cristina Purcarea

    2016-01-01

    Cave ice ecosystems represent a poorly investigated glacial environment. Diversity of cave ice bacteria and their distribution in perennial ice deposits of this underground glacial habitat could constitute a proxy for microbial response to climatic and environmental changes. Scarisoara Ice Cave (Romania) hosts one of the oldest and largest cave ice blocks worldwide. Here we report on cultured microbial diversity of recent, 400, and 900 years-old perennial ice from this cave, representing the ...

  14. Determinants of crop diversity and composition in Enset-coffee agroforestry homegardens of Southern Ethiopia

    Directory of Open Access Journals (Sweden)

    Tesfaye Abebe

    2013-08-01

    Full Text Available Households in much of the tropics depend for their livelihoods on the variety and continued production of food and other products that are provided by their own farms. In such systems, maintenance of agrobiodiversity and ensuring food security are important for the well being of the population. The enset-coffee agroforestry homegardens of Southern Ethiopia that are dominated by two native perennial crops, Coffee (Coffea arabica L. and Enset (Enset ventricosum Welw. Cheesman, are examples of such agricultural systems. This study was conducted in Sidama administrative zone of Southern Ethiopia to determine the factors that influence the diversity and composition of crops in the systems. Data were collected from 144 sample homegardens selected from four districts. Stepwise multiple regression analysis was used to relate indices of crop diversity and area share of major crops with the physical and socioeconomic factors. The study revealed that socioeconomic factors, mainly proximity to markets, affected negatively crop species richness. The production area of the main crops enset and coffee decreased with increasing proximity to market and road while that of maize and khat increased. At household level, farm size had a significant effect on area share of enset and coffee. As farm size increased the share of the cash crop, coffee increased but that of the staple, enset declined. Enset, which is the backbone of the system in terms of food security, is declining on small farms and the share of monoculture maize system is increasing. The trend towards declining agrobiodiversity, and reduction in the production area of the main perennial crops and their gradual replacement with monoculture fields could make the systems liable to instability and collapse. As these sites are high potential agricultural areas, intensification can be achieved by integrating high-value and more productive crops, such as fruits, spices and vegetables, while maintaining the

  15. Biogas production from energy crops and crop residues

    OpenAIRE

    Lehtomäki, Annimari

    2006-01-01

    The feasibility of utilising energy crops and crop residues in methane production through anaerobic digestion in boreal conditions was evaluated in this thesis. Potential boreal energy crops and crop residues were screened for their suitability for methane production, and the effects of harvest time and storage on the methane potential of crops was evaluated. Co-digestion of energy crops and crop residues with cow manure, as well as digestion of energy crops alone in batch leach bed reactors ...

  16. A guide to generalized additive models in crop science using SAS and R

    Directory of Open Access Journals (Sweden)

    Josefine Liew

    2015-06-01

    Full Text Available Linear models and generalized linear models are well known and are used extensively in crop science. Generalized additive models (GAMs are less well known. GAMs extend generalized linear models through inclusion of smoothing functions of explanatory variables, e.g., spline functions, allowing the curves to bend to better describe the observed data. This article provides an introduction to GAMs in the context of crop science experiments. This is exemplified using a dataset consisting of four populations of perennial sow-thistle (Sonchus arvensis L., originating from two regions, for which emergence of shoots over time was compared.

  17. Liming in Agricultural Production Models with and Without the Adoption of Crop-Livestock Integration

    OpenAIRE

    Francisco Carlos Mainardes da Silva; Luís Guilherme Sachs; Inês Cristina Batista Fonseca and; João Tavares Filho

    2015-01-01

    ABSTRACT Perennial forage crops used in crop-livestock integration (CLI) are able to accumulate large amounts of straw on the soil surface in no-tillage system (NTS). In addition, they can potentially produce large amounts of soluble organic compounds that help improving the efficiency of liming in the subsurface, which favors root growth, thus reducing the risks of loss in yield during dry spells and the harmful effects of “overliming”. The aim of this study was to test the effects of liming...

  18. 7 CFR 932.19 - Crop year and fiscal year.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Crop year and fiscal year. 932.19 Section 932.19 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Definitions...

  19. The current breeding programme on industrial crops in Indonesia

    International Nuclear Information System (INIS)

    There are two main constraints why breeding programme of most industrial crops can not be carried out smoothly. Firstly, most of the industrial crops belong to a perennial group with a relatively long life circle. Secondly, a greater part of them have a very limited genetic diversities in the nature. The low yield capacity per hectare of some crops are mainly due to certain diseases caused by fungi, bacteria, viruses and nematodes, besides several kinds of pests. Efforts have been done to overcome these problems, particularly through improvements of cultural practices, as well as plant breeding, however, major parts of those problems are not solved yet. This paper reviews several problems of industrial crops of economic importance in connection with several aspects of breeding works done in the past and recently faced by ICRI and farmers. It seems that nuclear techniques as a new means in breeding programmes is badly needed, especially to certain crops with a narrow spectrum of genetic diversities with special reference to seek for plants which are expected to be resistant to major diseases and pests. (author)

  20. Energy embodiment in Brazilian agriculture: an overview of 23 crops

    Directory of Open Access Journals (Sweden)

    João Paulo Soto Veiga

    2015-12-01

    Full Text Available The amount of energy required to produce a commodity or to supply a service varies from one production system to another and consequently giving rise to differing levels of environmental efficiency. Moreover, since energy prices have been continuously increasing over time, this energy amount may be a factor that has economic worth. Biomass production has a variety of end-products such as food, energy, and fiber; thus, taking into account the similarity in end-product of different crops (e.g.: sunflower, peanuts, or soybean for oil it is possible to evaluate which crops require less energy per functional unit, such as starch, oil, and protein. This information can be used in decision-making about policies for food safety or bioenergy. In this study, 23 crops were evaluated allowing for a comparison in terms of energy embodied per functional unit. Crops were grouped as follows: starch, oil, horticultural, perennial and fiber, to provide for a deeper analysis of alternatives for the groups, and subsidize further studies comparing conventional and alternative production systems such as organic or genetically modified organisms, in terms of energy. The best energy balance observed was whole sugarcane (juice, bagasse and straw with a surplus of 268 GJ ha−1 yr−1; palm shows the highest energy return on investment with a ratio of approximately 30:1. For carbohydrates and protein production, cassava and soybean, respectively, emerged as the crops offering the greatest energy savings in the production of these functional foods.

  1. Integrated Biological and Cultural Practices Can Reduce Crop Rotation Period of Organic Strawberries

    OpenAIRE

    Muramoto, J; Gliessman, SR; Koike, ST; Shennan, C; Bull, CT; Klonsky, K; Swezey, S

    2014-01-01

    A team of researchers conducted a replicated on-farm experiment with the break period between strawberry crops (continuous strawberries with broccoli residue incorporation, one-year break, two-year break, three-year break, and seven-year break) as the main plot and cultivar as the split plot in Moss Landing, Central Coastal California. We hypothesized that the use of non-host rotation crops for Verticillium wilt plus bio-fumigation with broccoli, incorporation of mustard cover crop residues, ...

  2. California Political Districts

    Data.gov (United States)

    California Department of Resources — This is a series of district layers pertaining to California'spolitical districts, that are derived from the California State Senateand State Assembly information....

  3. Water Footprints of Cellulosic Bioenergy Crops: Implications for Production on Marginal Lands

    Science.gov (United States)

    Hamilton, S. K.; Hussain, M. Z.; Bhardwaj, A. K.; Basso, B.; Abraha, M. G.; Robertson, G. P.

    2014-12-01

    Water availability often limits crop production, even in relatively humid climates, and crops vary in their water demand and water use efficiency. Crop production for biofuel (ethanol or biodiesel) offers an alternative to fossil energy sources but requires large amounts of land, and is therefore a more viable option if such crops could be produced on marginal lands that often have soils of poor water-holding capacity. The selection of an appropriate crop requires information on its water demand, water use efficiency, and drought tolerance, but such information is incompletely available for the suite of cellulosic biofuel crops currently under consideration. This study analyzed soil moisture profiles (time-domain reflectometry) to estimate evapotranspiration and water use efficiency of three leading candidate crops for cellulosic bioenergy production (switchgrass, Miscanthus, and maize) grown in a relatively humid climate (Midwestern United States) over four years (2010-13). These field observations of water use by these annual and perennial crops reveal their water use efficiency for biomass and biofuel production. Total growing season water use was remarkably consistent among crops and across years of varying soil water availability, including very favorable precipitation years as well as a drought year (2012). Water use efficiency was more variable and, for maize, depends on whether the maize serves for both grain and cellulosic biofuel production.

  4. Stream Health Sensitivity to Landscape Changes due to Bioenergy Crops Expansion

    Science.gov (United States)

    Nejadhashemi, A.; Einheuser, M. D.; Woznicki, S. A.

    2012-12-01

    Global demand for bioenergy has increased due to uncertainty in oil markets, environmental concerns, and expected increases in energy consumption worldwide. To develop a sustainable biofuel production strategy, the adverse environmental impacts of bioenergy crops expansion should be understood. To study the impact of bioenergy crops expansion on stream health, the adaptive neural-fuzzy inference system (ANFIS) was used to predict macroinvertebrate and fish stream health measures. The Hilsenhoff Biotic Index (HBI), Family Index of Biological Integrity (Family IBI), and Number of Ephemeroptera, Plecoptera, and Trichoptera taxa (EPT taxa) were used as macroinvertebrate measures, while the Index of Biological Integrity (IBI) was used for fish. A high-resolution biophysical model built using the Soil and Water Assessment Tool was used to obtain water quantity and quality variables for input into the ANFIS stream health predictive models. Twenty unique crop rotations were developed to examine impacts of bioenergy crops expansion on stream health in the Saginaw Bay basin. Traditional intensive row crops generated more pollution than current landuse conditions, while second-generation biofuel crops associated with less intensive agricultural activities resulted in water quality improvement. All three macroinvertebrate measures were negatively impacted during intensive row crop productions but improvement was predicted when producing perennial crops. However, the expansion of native grass, switchgrass, and miscanthus production resulted in reduced IBI relative to first generation row crops. This study demonstrates that ecosystem complexity requires examination of multiple stream health measures to avoid potential adverse impacts of landuse change on stream health.

  5. Miscanthus: A Review of European Experience with a Novel Energy Crop

    Energy Technology Data Exchange (ETDEWEB)

    Scurlock, J.M.O.

    1999-02-01

    Miscanthus is a tall perennial grass which has been evaluated in Europe over the past 5-10 years as a new bioenergy crop. The sustained European interest in miscanthus suggests that this novel energy crop deserves serious investigation as a possible candidate biofuel crop for the US alongside switchgrass. To date, no agronomic trials or trial results for miscanthus are known from the conterminous US, so its performance under US conditions is virtually unknown. Speculating from European data, under typical agricultural practices over large areas, an average of about 8t/ha (3t/acre dry weight) may be expected at harvest time. As with most of the new bioenergy crops, there seems to be a steep ''learning curve.'' Establishment costs appear to be fairly high at present (a wide range is reported from different European countries), although these may be expected to fall as improved management techniques are developed.

  6. Climate protection and energy crops. Potential for greenhouse gas emission reduction through crop rotation and crop planning; Klimaschutz und Energiepflanzenanbau. Potenziale zur Treibhausgasemissionsminderung durch Fruchtfolge- und Anbauplanung

    Energy Technology Data Exchange (ETDEWEB)

    Eckner, Jens [Thueringer Landesanstalt fuer Landwirtschaft (Germany); Peter, Christiane; Vetter, Armin

    2015-07-01

    The EVA project compares nationwide energy crops and crop rotations on site-specific productivity. In addition to agronomic suitability for cultivation economic and environmental benefits and consequences are analyzed and evaluated. As part of sustainability assessment of the tested cultivation options LCAs are established. The model MiLA developed in the project uses empirical test data and site parameters to prepare the inventory balances. At selected locations different cultivation and fertilization regimes are examined comparatively. In the comparison of individual crops and crop rotation combinations cultivation of W.Triticale-GPS at the cereals favor location Dornburg causes the lowest productrelated GHG-emissions. Due to the efficient implementation of nitrogen and the substrate properties of maize is the cultivation despite high area-related emissions and N-expenses at a low level of emissions. Because of the intensity the two culture systems offer lower emissions savings potentials with high area efficiency. Extensification with perennial alfalfagrass at low nitrogen effort and adequate yield performance show low product-related emissions. Closing the nutrient cycles through a recirculation of digestates instead of using mineral fertilization has a climate-friendly effect. Adapted intensifies of processing or reduced tillage decrease diesel consumption and their related emissions.

  7. Assessing the Impacts of Land Use Change from Cotton to Perennial Bioenergy Grasses on Hydrological Fluxes and Water Quality in a Semi-Arid Agricultural Watershed Using the APEX Model

    Science.gov (United States)

    Chen, Y.; Ale, S.; Rajan, N.

    2015-12-01

    The semi-arid Texas High Plains (THP) region, where cotton (Gossypium hirsutum L.) is grown in vast acreage, has the potential to grow perennial bioenergy grasses. A change in land use from cotton cropping systems to perennial grasses such as Alamo switchgrass (Panicum virgatum L.) and Miscanthus giganteus (Miscanthus sinensis Anderss. [Poaceae]) can significantly affect regional hydrologic cycle and water quality. Assessing the impacts of this potential land use change on hydrology and water quality enables the environmental assessment of feasibility to grow perennial grasses in this region to meet the U.S. national bioenergy target of 2022. The Agricultural Policy/Environmental eXtender (APEX) model was used in this study to assess the impacts of replacing cotton with switchgrass and Miscanthus on water and nitrogen balances in the upstream subwatershed of the Double Mountain Fork Brazos watershed in the THP, which contains 52% cotton land use. The APEX model was initially calibrated against observed streamflow and crop yield data. Since observed data on nitrogen loads in streamflow was not available for this subwatershed, we calibrated the APEX model against the SWAT-simulated nitrogen loads at the outlet of this subwatershed, which were obtained in a parallel study. The calibrated APEX model was used to simulate the impacts of land use change from cotton to Miscanthus and switchgrass on surface and subsurface water and nitrogen balances. Preliminary results revealed that the average (1994-2009) annual surface runoff decreased by 84% and 66% under the irrigated and dryland switchgrass scenarios compared to the baseline scenarios. Average annual percolation increased by 106% and 57% under the irrigated and dryland switchgrass scenarios relative to the baseline scenarios. Preliminary results also indicated Miscanthus and switchgrass appeared to be superior to cotton in terms of better water conservation and water quality, and minimum crop management requirements.

  8. Energy Crops and their Implications on Soil Carbon Sequestration, Surface Energy and Water Balance

    Science.gov (United States)

    Song, Y.; Barman, R.; Jain, A. K.

    2011-12-01

    The quest to meet growing energy demand with low greenhouse gas emissions has increased attention on the potential of existing and advanced biomass energy crops. Potential energy crops include row crops such as corn, and perennial grasses such as switchgrass. However, a massive expansion of bioenergy crops raises many questions such as: how and where to grow energy crops; and what will be the impacts of growing large scale biofuel crops on the terrestrial hydrological cycle, the surface energy budget, soil carbon sequestration and the concurrent effects on the climate system. An integrated modeling system is being developed with in the framework of a land surface model, the Integrated Science Assessment Model (ISAM), and being applied to address these questions.This framework accounts for the biophysical, physiological and biogeochemical systems governing important processes that regulate crop growth including water, energy and nutrient cycles within the soil-plant-atmosphere system. One row crop (Corn) and two energy crops (Switchgrass and Miscanthus) are studied in current framework. Dynamic phenology processes and parameters for simulating each crop have been developed using observed data from a north to south gradient of field trial sites. This study will specifically focus on the agricultural regions in the US and in Europe. The potential productivity of these three crops will be assessed in terms of carbon sequestration, surface energy and water balance and their spatial variability. This study will help to quantify the importance of various environmental aspects towards modeling bioenergy crops and to better understand the spatial and temporal dynamics of bioenergy crop yields.

  9. Alternative scenarios of bioenergy crop production in an agricultural landscape and implications for bird communities.

    Science.gov (United States)

    Blank, Peter J; Williams, Carol L; Sample, David W; Meehan, Timothy D; Turner, Monica G

    2016-01-01

    Increased demand and government mandates for bioenergy crops in the United States could require a large allocation of agricultural land to bioenergy feedstock production and substantially alter current landscape patterns. Incorporating bioenergy landscape design into land-use decision making could help maximize benefits and minimize trade-offs among alternative land uses. We developed spatially explicit landscape scenarios of increased bioenergy crop production in an 80-km radius agricultural landscape centered on a potential biomass-processing energy facility and evaluated the consequences of each scenario for bird communities. Our scenarios included conversion of existing annual row crops to perennial bioenergy grasslands and conversion of existing grasslands to annual bioenergy row crops. The scenarios explored combinations of four biomass crop types (three potential grassland crops along a gradient of plant diversity and one annual row crop [corn]), three land conversion percentages to bioenergy crops (10%, 20%, or 30% of row crops or grasslands), and three spatial configurations of biomass crop fields (random, clustered near similar field types, or centered on the processing plant), yielding 36 scenarios. For each scenario, we predicted the impact on four bird community metrics: species richness, total bird density, species of greatest conservation need (SGCN) density, and SGCN hotspots (SGCN birds/ha ≥ 2). Bird community metrics consistently increased with conversion of row crops to bioenergy grasslands and consistently decreased with conversion of grasslands to bioenergy row crops. Spatial arrangement of bioenergy fields had strong effects on the bird community and in some cases was more influential than the amount converted to bioenergy crops. Clustering grasslands had a stronger positive influence on the bird community than locating grasslands near the central plant or at random. Expansion of bioenergy grasslands onto marginal agricultural lands will

  10. Alternative scenarios of bioenergy crop production in an agricultural landscape and implications for bird communities.

    Science.gov (United States)

    Blank, Peter J; Williams, Carol L; Sample, David W; Meehan, Timothy D; Turner, Monica G

    2016-01-01

    Increased demand and government mandates for bioenergy crops in the United States could require a large allocation of agricultural land to bioenergy feedstock production and substantially alter current landscape patterns. Incorporating bioenergy landscape design into land-use decision making could help maximize benefits and minimize trade-offs among alternative land uses. We developed spatially explicit landscape scenarios of increased bioenergy crop production in an 80-km radius agricultural landscape centered on a potential biomass-processing energy facility and evaluated the consequences of each scenario for bird communities. Our scenarios included conversion of existing annual row crops to perennial bioenergy grasslands and conversion of existing grasslands to annual bioenergy row crops. The scenarios explored combinations of four biomass crop types (three potential grassland crops along a gradient of plant diversity and one annual row crop [corn]), three land conversion percentages to bioenergy crops (10%, 20%, or 30% of row crops or grasslands), and three spatial configurations of biomass crop fields (random, clustered near similar field types, or centered on the processing plant), yielding 36 scenarios. For each scenario, we predicted the impact on four bird community metrics: species richness, total bird density, species of greatest conservation need (SGCN) density, and SGCN hotspots (SGCN birds/ha ≥ 2). Bird community metrics consistently increased with conversion of row crops to bioenergy grasslands and consistently decreased with conversion of grasslands to bioenergy row crops. Spatial arrangement of bioenergy fields had strong effects on the bird community and in some cases was more influential than the amount converted to bioenergy crops. Clustering grasslands had a stronger positive influence on the bird community than locating grasslands near the central plant or at random. Expansion of bioenergy grasslands onto marginal agricultural lands will

  11. A comparative study of AMF diversity in annual and perennial plant species from semiarid gypsum soils.

    Science.gov (United States)

    Alguacil, M. M.; Torrecillas, E.; Roldán, A.; Díaz, G.; Torres, P.

    2012-04-01

    The arbuscular mycorrhizal fungi (AMF) communities composition regulate plant interactions and determine the structure of plant communities. In this study we analysed the diversity of AMF in the roots of two perennial gypsophyte plant species, Herniaria fruticosa and Senecio auricula, and an annual herbaceous species, Bromus rubens, growing in a gypsum soil from a semiarid area. The objective was to determine whether perennial and annual host plants support different AMF communities in their roots and whether there are AMF species that might be indicators of specific functional plant roles in these ecosystems. The roots were analysed by nested PCR, cloning, sequencing of the ribosomal DNA small subunit region and phylogenetic analysis. Twenty AMF sequence types, belonging to the Glomus group A, Glomus group B, Diversisporaceae, Acaulosporaceae, Archaeosporaceae and Paraglomeraceae, were identified. Both gypsophyte perennial species had differing compositions of the AMF community and higher diversity when compared with the annual species, showing preferential selection by specific AMF sequences types. B. rubens did not show host specificity, sharing the full composition of its AMF community with both perennial plant species. Seasonal variations in the competitiveness of AM fungi could explain the observed differences in AMF community composition, but this is still a working hypothesis that requires the analysis of further data obtained from a higher number of both annual and perennial plant species in order to be fully tested.

  12. Landscape patterns of bioenergy in a changing climate: implications for crop allocation and land-use competition.

    Science.gov (United States)

    Graves, Rose A; Pearson, Scott M; Turner, Monica G

    2016-03-01

    Rural landscapes face changing climate, shifting development pressure, and loss of agricultural land. Perennial bioenergy crops grown on existing agricultural land may provide an opportunity to conserve rural landscapes while addressing increased demand for biofuels. However, increased bioenergy production and changing land use raise concerns for tradeoffs within the food-energy-environment trilemma. Heterogeneity of climate, soils, and land use complicate assessment of bioenergy potential in complex landscapes, creating challenges to evaluating future tradeoffs. The hypothesis addressed herein is that perennial bioenergy production can provide an opportunity to avoid agricultural land conversion to development. Using a process-based crop model, we assessed potential bioenergy crop growth through 2100 in a southern Appalachian Mountain region and asked: (1) how mean annual yield differed among three crops (switchgrass Panicum virgatum, giant miscanthus Miscanthus x giganteus, and hybrid poplar Populus x sp.) under current climate and climate change scenarios resulting from moderate and very high greenhouse gas emissions; (2) how maximum landscape yield, spatial allocation of crops, and bioenergy hotspots (areas with highest potential yield) varied among climate scenarios; and (3) how bioenergy hotspots overlapped with current crop production or lands with high development pressure. Under both climate change scenarios, mean annual yield of perennial grasses decreased (-4% to -39%), but yield of hybrid poplar increased (+8% to +20%) which suggests that a switch to woody crops would maximize bioenergy crop production. In total, maximum landscape yield increased by up to 90 000 Mg/yr (6%) in the 21st century due to increased poplar production. Bioenergy hotspots (> 18 Mg x ha(-1) x yr(-1)) consistently overlapped with high suburban/exurban development likelihood and existing row crop production. If bioenergy production is constrained to marginal (non-crop) lands

  13. Landscape patterns of bioenergy in a changing climate: implications for crop allocation and land-use competition.

    Science.gov (United States)

    Graves, Rose A; Pearson, Scott M; Turner, Monica G

    2016-03-01

    Rural landscapes face changing climate, shifting development pressure, and loss of agricultural land. Perennial bioenergy crops grown on existing agricultural land may provide an opportunity to conserve rural landscapes while addressing increased demand for biofuels. However, increased bioenergy production and changing land use raise concerns for tradeoffs within the food-energy-environment trilemma. Heterogeneity of climate, soils, and land use complicate assessment of bioenergy potential in complex landscapes, creating challenges to evaluating future tradeoffs. The hypothesis addressed herein is that perennial bioenergy production can provide an opportunity to avoid agricultural land conversion to development. Using a process-based crop model, we assessed potential bioenergy crop growth through 2100 in a southern Appalachian Mountain region and asked: (1) how mean annual yield differed among three crops (switchgrass Panicum virgatum, giant miscanthus Miscanthus x giganteus, and hybrid poplar Populus x sp.) under current climate and climate change scenarios resulting from moderate and very high greenhouse gas emissions; (2) how maximum landscape yield, spatial allocation of crops, and bioenergy hotspots (areas with highest potential yield) varied among climate scenarios; and (3) how bioenergy hotspots overlapped with current crop production or lands with high development pressure. Under both climate change scenarios, mean annual yield of perennial grasses decreased (-4% to -39%), but yield of hybrid poplar increased (+8% to +20%) which suggests that a switch to woody crops would maximize bioenergy crop production. In total, maximum landscape yield increased by up to 90 000 Mg/yr (6%) in the 21st century due to increased poplar production. Bioenergy hotspots (> 18 Mg x ha(-1) x yr(-1)) consistently overlapped with high suburban/exurban development likelihood and existing row crop production. If bioenergy production is constrained to marginal (non-crop) lands

  14. Bioenergy production from perennial energy crops: A consequential LCA of 12 bioenergy scenarios including land use changes

    DEFF Research Database (Denmark)

    Tonini, Davide; Hamelin, Lorie; Wenzel, Henrik;

    2012-01-01

    and IV) co-firing in large scale coal-fired CHP plants. Soil carbon changes, direct and indirect land use changes as well as uncertainty analysis (sensitivity, MonteCarlo) were included in the LCA. Results showed that global warming was the bottleneck impact, where only two scenarios, namely willow...... and Miscanthus co-firing, allowed for an improvement as compared with the reference (-82 and -45 t CO2-eq. ha-1, respectively). The indirect land use changes impact was quantified as 310 ± 170 t CO2-eq. ha-1, representing a paramount average of 41% of the induced greenhouse gas emissions. The uncertainty...

  15. GM Crops: Patently Wrong?

    OpenAIRE

    Wilson, J.

    2007-01-01

    Abstract This paper focuses on the ethical justifiability of patents on Genetically Modified (GM) crops. I argue that there are three distinguishing features of GM crops that make it unethical to grant patents on GM crops, even if we assume that the patent system is in general justified. The first half of the paper critiques David Resnik’s recent arguments in favor of patents on GM crops. Resnik argues that we should take a consequentialist approach to the issue, and that the best way to do s...

  16. Influence of perennial colonies of piscivorous birds on soil nutrient contents in a temperate humid climate

    DEFF Research Database (Denmark)

    Breuning-Madsen, Henrik; Ehlers-Koch, Camilla; Gregersen, Jens;

    2010-01-01

    , but the bird’s influence on the soil conditions has only in few cases been studied in detail. In this study the influence of perennial colonies of piscivorous birds on soil nutrient contents and accumulation of carbon, nitrogen and phosphorus in a humid climate has been determined by measuring p......During the last decades, the number of perennial colonies of piscivorous birds especially cormorant colonies in North-western Europe has grown rapidly due to protection. Their impact on vegetation has been recognized, as many trees containing perennial colonies of piscivorous birds have collapsed...... reference soil, especially in the top horizons, and the magnitude of increase in nutrient content varied with the bird-dropping density and the age of the colony. In addition, soil influenced by cormorants had a higher electric conductivity compared to the control reference and can be classified as saline...

  17. Genomic prediction in families of perennial ryegrass based on genotyping-by-sequencing

    DEFF Research Database (Denmark)

    Ashraf, Bilal

    In this thesis we investigate the potential for genomic prediction in perennial ryegrass using genotyping-by-sequencing (GBS) data. Association method based on family-based breeding systems was developed, genomic heritabilities, genomic prediction accurancies and effects of some key factors wer e...... prediction. Overall, GBS allows for genomic prediction in breeding families of perennial ryegrass and holds good potential to expedite genetic gain and encourage the application of genomic prediction......In this thesis we investigate the potential for genomic prediction in perennial ryegrass using genotyping-by-sequencing (GBS) data. Association method based on family-based breeding systems was developed, genomic heritabilities, genomic prediction accurancies and effects of some key factors wer...

  18. Genomics-Assisted Exploitation of Heterosis in Perennial Ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Islam, Md. Shofiqul

    ryegrass for the development of improved varieties. During his PhD studies, Mohammad Shofiqul Islam studied the feasibility of developing novel hybrid breeding schemes based on cytoplasmic male sterility (CMS) systems in perennial ryegrass. He successfully completed the assembly and annotation of a male......-fertile perennial ryegrass mitochondrial genome, and identified candidate genes responsible for the CMS phenotype by comparing male-fertile and male-sterile mitochondrial genomes. His findings constitute a good basis for continuing research to produce hybrid grass varieties to address the future needs......, breeding activities have been carried out to improve the population and develop synthetic varieties. This does not fully exploit the potential of heterosis, however. Hybrid breeding is an alternative strategy and provides opportunities to fully exploit the genetically available heterosis in perennial...

  19. Effects of stored feed cropping systems and farm size on the profitability of Maine organic dairy farm simulations.

    Science.gov (United States)

    Hoshide, A K; Halloran, J M; Kersbergen, R J; Griffin, T S; DeFauw, S L; LaGasse, B J; Jain, S

    2011-11-01

    United States organic dairy production has increased to meet the growing demand for organic milk. Despite higher prices received for milk, organic dairy farmers have come under increasing financial stress due to increases in concentrated feed prices over the past few years, which can make up one-third of variable costs. Market demand for milk has also leveled in the last year, resulting in some downward pressure on prices paid to dairy farmers. Organic dairy farmers in the Northeast United States have experimented with growing different forage and grain crops to maximize on-farm production of protein and energy to improve profitability. Three representative organic feed systems were simulated using the integrated farm system model for farms with 30, 120, and 220 milk cows. Increasing intensity of equipment use was represented by organic dairy farms growing only perennial sod (low) to those with corn-based forage systems, which purchase supplemental grain (medium) or which produce and feed soybeans (high). The relative profitability of these 3 organic feed systems was strongly dependent on dairy farm size. From results, we suggest smaller organic dairy farms can be more profitable with perennial sod-based rather than corn-based forage systems due to lower fixed costs from using only equipment associated with perennial forage harvest and storage. The largest farm size was more profitable using a corn-based system due to greater economies of scale for growing soybeans, corn grain, winter cereals, and corn silages. At an intermediate farm size of 120 cows, corn-based forage systems were more profitable if perennial sod was not harvested at optimum quality, corn was grown on better soils, or if milk yield was 10% higher. Delayed harvest decreased the protein and energy content of perennial sod crops, requiring more purchased grain to balance the ration and resulting in lower profits. Corn-based systems were less affected by lower perennial forage quality, as corn silage

  20. Concepts in crop rotations

    Science.gov (United States)

    Crop rotations have been a part of civilization since the Middle Ages. With colonization of what would become the United States came new crops of tobacco, cotton, and corn, the first two of which would play significant roles in both the economic beginnings and social fabric of the new country, how ...

  1. Numerical simulation of cropping

    DEFF Research Database (Denmark)

    Tvergaard, Viggo; Hutchinson, John W.

    2014-01-01

    Cropping is a cutting process whereby opposing aligned blades create a shearing failure by exerting opposing forces normal to the surfaces of a metal sheet or plate. Building on recent efforts to quantify cropping, this paper formulates a plane strain elastic-plastic model of a plate subject to s...

  2. Simulation of crop evapotranspiration and crop coefficient in weighing lysimeters

    Science.gov (United States)

    Accurate quantification of crop evapotranspiration (ET) is critical in optimizing irrigation water productivity, especially, in the semiarid regions of the world where limited rainfall is supplemented by irrigation for profitable crop production. In this context, cropping system models are potential...

  3. Molecular Characterization Of The Vernalization Locus VRN1 In Perennial Ryegrass

    DEFF Research Database (Denmark)

    Asp, Torben; Byrne, Stephen; Andersen, Jeppe R;

    Vernalization, the requirement of a period of low temperature to induce transition from vegetative to reproductive state, is an important trait in grasses. The objective of this study was to identify the causative polymorphism(s) for the variation in vernalization requirement at the VRN1 locus in...... perennial ryegrass (Lolium perenne). Two allelic BAC clones of the VRN1 locus from the two genotypes Veyo and Falster with contrasting vernalization requirements were identified, sequenced, and characterized. The region surrounding the VRN1 locus in perennial ryegrass showed micro-colinearity to the...

  4. Influence of perennial colonies of piscivorous birds on soil nutrient contents in a temperate humid climate

    DEFF Research Database (Denmark)

    Breuning-Madsen, Henrik; Ehlers-Koch, Camilla; Gregersen, Jens;

    2010-01-01

    During the last decades, the number of perennial colonies of piscivorous birds especially cormorant colonies in North-western Europe has grown rapidly due to protection. Their impact on vegetation has been recognized, as many trees containing perennial colonies of piscivorous birds have collapsed...... conductivity and content of carbon, nitrogen, phosphorus, calcium and potassium in a reference area and in two cormorant sub-colonies. In general, the soils exposed to cormorant guano had lower pH and higher contents of plant available phosphorus, calcium and potassium compared to the control reference soil...... influence of the cormorants the herb vegetation below the nesting areas has been changed....

  5. The Perennial Ryegrass GenomeZipper – Targeted Use of Genome Resources for Comparative Grass Genomics

    DEFF Research Database (Denmark)

    Pfeiffer, Matthias; Martis, Mihaela; Asp, Torben;

    2013-01-01

    (Lolium perenne) genome on the basis of conserved synteny to barley (Hordeum vulgare) and the model grass genome Brachypodium (Brachypodium distachyon) as well as rice (Oryza sativa) and sorghum (Sorghum bicolor). A transcriptome-based genetic linkage map of perennial ryegrass served as a scaffold to...... assignment of 3,315 out of 8,876 previously unmapped genes to the respective chromosomes. In total, the GenomeZipper incorporates 4,035 conserved grass gene loci, which were used for the first genome-wide sequence divergence analysis between perennial ryegrass, barley, Brachypodium, rice, and sorghum. The...

  6. Surfin’ California with Whitman and The Beach Boys

    DEFF Research Database (Denmark)

    Balle, Søren Hattesen

    2006-01-01

    While Whitman only wrote one poem about California in 1860, The Beach Boys wrote and produced several songs about it in the years between 1962 and 1966. Apart from the hundred years separating Whitman and The Beach boys, a cultural gap also exists between them. Whitman represents the high point...... are haunted by and pick up on Whitman’s image of the Californian beach results in a kind of Bloomean misprision, in the sense that they (re)inscribe it in a sixties’ context of youth and consumer culture. To Whitman, the shores of the American West coast incarnate the home of perennial homelessness...... of American literary Romanticism, whereas The Beach Boys became the sixties’ most well-known pop icon of surf music and surf culture. Nevertheless, their common interest in California as a particular topographic image of the American West invites comparison and further study. This paper aims to make...

  7. Crop Sequence Economics in Dynamic Cropping Systems

    Science.gov (United States)

    No-till production systems allow more intensified and diversified production in the northern Great Plains; however, this has increased the need for information on improving economic returns through crop sequence selection. Field research was conducted 6 km southwest of Mandan ND to determine the inf...

  8. The Biogeochemical Cycling of Nitrogen in Annual and Perennial Agroecosystems

    Science.gov (United States)

    Fortuna, A.; Cogger, C.

    2010-12-01

    Organic agricultural systems are dependent upon fertilizer amendments that undergo ammonification prior to the release of plant available nitrogen (N) as ammonium. Ammonia may be further transformed via nitrification to nitrate resulting in greater potential for leaching or volatilization. Additions of plant residue and animal amendments contribute to soil N and carbon pools improving soil quality and the potential for release of ammonium. Therefore, agricultural systems that relay on organic inputs as fertilizer sources must be monitored to insure stored nutrients are released during plant uptake to prevent N losses. Our experimental design allows us to determine the effects of several organic cropping systems and fertility regimes on plant available N, nitrification potential and nitrifier gene copy number g-1 dry soil across season in a grass ley and two annual systems receiving chicken manure or compost. Nitrification potentials measured via the shaken slurry method, KCl extractable N and ammonia oxidizing bacteria (AOB) and archaea (AOA) gene copy numbers g-1 dry soil measured via quantitative PCR were monitored. Nitrification potentials measured in March revealed increases in nitrification where compost had historically been applied (7.78 vs. 5.26 ± 0.856). Treatment affects were significant in June the closest date to application of amendments and when ammonification from soil N was optimal. Animal amendments were added yearly in annual systems (31.0 ± 2.91) vs every three years in the ley pasture (12.9 ± 2.91) resulting in a management effect. Copy numbers of AOB (2.69 x 108 ± 4.94 x 107) were greatest in plots receiving compost vs chicken manure. Preliminary measurements of AOA gene copy numbers reveal a similar trend to that of AOB. But, gene copy numbers of AOA (105 to 106) were lower than those of AOB. Nitrification potentials were not different across treatments in September, 11.8 ± 2.28. This research will contribute to the development of novel

  9. Frequency of Verticillium species in commercial spinach fields and transmission of V. dahliae from spinach to subsequent lettuce crops

    Science.gov (United States)

    Verticillium wilt, caused by Verticillium dahlia,e is a devastating disease of lettuce in California. The disease on lettuce is currently restricted to a small geographic area in the central coastal California, even though cropping patterns in other coastal lettuce production regions in the state ar...

  10. Breeding of catch crops - a way to reduce nitrate leaching from arable land

    Energy Technology Data Exchange (ETDEWEB)

    Rydberg, I. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Plant Biology

    1998-12-01

    Nitrogen in the form of nitrate is soluble in water and nitrate can therefore leach into water systems. Several changes of agricultural practice the last 50 years have promoted nitrogen leaching. Crops with long vegetation periods give less leaching problems than crops with short growing seasons. In Sweden, areas in the South West have the most severe leaching. A catch crop can be defined as a crop grown between two main commercial crops, with the specific mission to reduce leaching of nutrients. The motivation for this plant breeding project was the positive effect of decreased leaching obtained when undersown catch crops were used. A research programme was initiated with the aim of developing a theoretical ideotype for an optimal catch crop and of identifying species for use in applied agriculture. The characteristics of the ideotype include the interaction of the catch crop with the main crop (low influence on the yield of the main crop), its function as a catch crop for nitrogen (high influence on nitrate leaching) and presumed consequences in the cropping system (low influence on crop rotation). 134 species (1083 different accessions) of both agrarian, non agrarian, domesticated and non domesticated origin were included in a screening. The work included model experiments in the greenhouse for responses to reduced light and uptake of nitrogen using {sup 15}N fertilizer as well as field trials, testing growth of catch crop, grain yield of the main crop, and reduction of nitrate in the soil. The ideotype was very useful in the screening, and promising species were identified. A number of biennial and perennial species proved to comply with the ideotype and possess prerequisites beneficial for catch crop purposes. One of them, chicory, showed that a depletion of nitrate during periods with risk of high nitrate leaching, could be combined with later access to this nutrient by the succeeding crop. Legumes had problems in combining all traits presented in the

  11. Cultivar by environment effects of perennial ryegrass cultivars selected for high water soluble carbohydrates managed under differing precipitation levels

    Science.gov (United States)

    Historic results of perennial ryegrass (Lolium perenne L.) breeding include improved disease resistance, biomass, and nutritional quality. Yet, lack of tolerance to water stress limits its wise use. Recent efforts to increase water soluble carbohydrate (WSC) content in perennial ryegrass may incre...

  12. Increasing Cultivar Diversity of Processing Tomato under Large Scale Organic Production in California

    OpenAIRE

    Barrios Masias, Felipe; Jackson, Louise

    2008-01-01

    At an organic farm in California, higher plant diversity was hypothesized to enhance ecosystem functions and services. Plant diversity was manipulated temporally and spatially: mustard cover crop vs. no cover crop (fallow) in winter, and mixtures with one (farmer’s best choice), three, or five processing tomato cultivars in summer. Soil N, soil microbial biomass, crop nutrient uptake, canopy light interception, disease, GHG emissions and biomass were measured. Results show that the mustard co...

  13. Treatment of 48 Cases of Perennial Allergic Rhinitis with Thunder-fire Moxibustion

    Institute of Scientific and Technical Information of China (English)

    蒋洁明; 张沈煜

    2010-01-01

    @@ Perennial allergic rhinitis is an allergic reaction of the nasal mucosa.It is characterized by paroxysmal and repeated runny nose,sneeze,stuffy nose,rhinocnesmus and nasal mucosa edema.The author used "Doctor ZHAO's thunder-fire moxibustion" in treating 48 cases of this disease.Now it is reported as follows.

  14. Extending the shelf life of flower bulbs and perennials in consumer packages by modiefied atmosphere packaging

    NARCIS (Netherlands)

    Gude, H.; Dijkema, M.H.G.E.; Miller, C.T.

    2011-01-01

    The quality of flower bulbs and herbaceous perennials in consumer packages declines rapidly due to sprouting and drying out. The present study was undertaken to develop Modified Atmosphere Packages (MAP) with suitable filling materials for a prolonged shelf life of different species of flower bulbs

  15. Silicon induced systemic defense responses in perennial ryegrass against Magnaporthe oryzae infection

    Science.gov (United States)

    Sustainable integrated disease management for gray leaf spot of perennial ryegrass may involve use of plant defense elicitors with compatible traditional fungicides to reduce disease incidence and severity. Silicon (Si) is a potential inducer or modulator of plant defenses against different pathogen...

  16. In search of a perennial philosophy for behavioral health integration in primary care.

    Science.gov (United States)

    Mauksch, Larry B; Fogarty, Colleen T

    2016-06-01

    The "perennial philosophy," a concept religious scholars have studied for centuries, represents a search for the values, themes, and constructs that transcend individual religions. Can we who develop and disseminate behavioral health integration in primary care step back from individual models to identify our perennial philosophy? If so, what are the components? What does the evidence tell us? What do we need to learn? Four case examples are presented which represent many patients seen by both of us-a family therapist and a family physician-over our combined 55 years of collaborative practice within integrated primary care settings. Can these patients be cared for in a primary care setting? Our experience provides a simple answer-yes. However, providing care for this range of patients requires variability in team configurations, frequency of visits, lengths of relationships, and interventional strategies. Is there a perennial philosophy of how to design and implement the integration of behavioral health in primary care? We think there should be. we highlight a recent publication from the Eugene S. Farley, Jr. Health Policy Center, entitled "Core Competencies For Behavioral Health Providers Working In Primary Care." The authors purposefully transcend models in delineating eight core competencies. Embedded within these competencies are common or perennial factors. These factors may guide our field going forward, helping us avoid "religious" divisions, seek to understand diverse designs, and embrace integration of models to meet the needs of the populations and teams we serve. (PsycINFO Database Record

  17. Temporal dynamics of the metabolically active rumen bacteria colonizing fresh perennial ryegrass

    NARCIS (Netherlands)

    Huws, Sharon A.; Edwards, Joan E.; Creevey, Christopher J.; Stevens, Pauline Rees; Lin, Wanchang; Girdwood, Susan E.; Pachebat, Justin A.; Kingston-Smith, Alison H.

    2016-01-01

    This study investigated successional colonization of fresh perennial ryegrass (PRG) by the rumen microbiota over time. Fresh PRG was incubated in sacco in the rumens of three Holstein × Friesian cows over a period of 8 h, with samples recovered at various times. The diversity of attached bacteria

  18. From the Lab Bench: Differences in annual and perennial grasses in meeting cattle production goals

    Science.gov (United States)

    A column was written that provided the advantages and disadvantages of annual warm- and cool-season grasses. Warm-season annual grasses can increase the supply of forage during the summer slump in cool-season perennial grass growth. Utilization of toxic endophyte-infected tall fescue pastures can ...

  19. Removal of nitrogen from wastewater with perennial ryegrass/artificial aquatic mats biofilm combined system

    Institute of Scientific and Technical Information of China (English)

    Chongjun Chen; Rui Zhang; Liang Wang; Weixiang Wu; Yingxu Chen

    2013-01-01

    To develop a cost-effective combined phytoremediation and biological process,a combined perennial ryegrass/artificial aquatic mat biofilm reactor was used to treat synthetic wastewater.Influent ammonium loading,reflux ratio,hydraulic retention time (HRT) and temperature all had significant effects on the treatment efficiency.The results indicated that the effluent concentration of ammonium increased with increasing influent ammonium loading.The reactor temperature played an important role in the nitrification process.The ammonium removal efficiency significantly decreased from 80% to 30%-50% when the reactor temperature dropped to below 10℃.In addition,the optimal nitrogen removal condition was a reflux ratio of 2.The nitrate and ammonium concentration of the effluent were consistent with the HRT of the combined system.The chemical oxygen demand (COD) removal efficiency was at a high level during the whole experiment,being almost 80% after the start-up,and then mostly above 90%.The direct uptake of N by the perennial ryegrass accounted for 18.17% of the total N removal by the whole system.The perennial ryegrass absorption was a significant contributor to nitrogen removal in the combined system.The result-illustrated that the combined perennial ryegrass/artificial aquatic mat biofilm reactor demonstrated good performance in ammonium,total N and COD removal.

  20. Cultivar effects of perennial ryegrass on herbage intake by grazing dairy cows

    NARCIS (Netherlands)

    Smit, H.J.

    2006-01-01

    Perennial ryegrass is the most abundant grass species in temperate climates. An increased herbage intake of dairy cows by breeding new cultivars could have a large potential impact on agriculture. The effects of cultivars on sward structure, nutritive value, physical characteristics and disease resi

  1. 30 CFR 816.57 - Hydrologic balance: Activities in or adjacent to perennial or intermittent streams.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Hydrologic balance: Activities in or adjacent to perennial or intermittent streams. 816.57 Section 816.57 Mineral Resources OFFICE OF SURFACE... PERMANENT PROGRAM PERFORMANCE STANDARDS-SURFACE MINING ACTIVITIES § 816.57 Hydrologic balance: Activities...

  2. Photoperiodic regulation of flowering in perennial ryegrass involving a CONSTANS-like homolog

    DEFF Research Database (Denmark)

    Martin, J.; Storgaard, M.; Andersen, C.H.;

    2004-01-01

    Photoperiod and vernalization are the two key environmental factors of the. oral induction of perennial ryegrass (Lolium perenne L.). Transition from vegetative to reproductive growth will only occur after an extended vernalization period, followed by an increase in day length and temperature. Here...

  3. Progress on the introgression of Sclerotinia resistance genes from wild perennial Helianthus species into cultivated sunflower

    Science.gov (United States)

    The necrotrophic fungus Sclerotinia sclerotiorum (Lib.) de Bary attacks sunflower (Helianthus annuus L.) causing root, stalk, and head rot, and is one of the most damaging and difficult-to-control sunflower diseases. Some wild perennial Helianthus species have been identified to contain abundant res...

  4. Sustainability of perennial grass yields as bioenergy feedstock for the southeast

    Science.gov (United States)

    Warm-season perennial grasses will be part of the biomass production system in the Southeast for the emerging bioenergy industry. Among the candidates for dedicated feedstocks are energy cane (Sacchurum sp.), Miscanthus x gigantius, switchgrass (Panicum virgatum), and napiergrass (Pennistem purpure...

  5. The effects of perennial ryegrass and alfalfa on microbial abundance and diversity in petroleum contaminated soil

    International Nuclear Information System (INIS)

    Enhanced rhizosphere degradation uses plants to stimulate the rhizosphere microbial community to degrade organic contaminants. We measured changes in microbial communities caused by the addition of two species of plants in a soil contaminated with 31,000 ppm of total petroleum hydrocarbons. Perennial ryegrass and/or alfalfa increased the number of rhizosphere bacteria in the hydrocarbon-contaminated soil. These plants also increased the number of bacteria capable of petroleum degradation as estimated by the most probable number (MPN) method. Eco-Biolog plates did not detect changes in metabolic diversity between bulk and rhizosphere samples but denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified partial 16S rDNA sequences indicated a shift in the bacterial community in the rhizosphere samples. Dice coefficient matrices derived from DGGE profiles showed similarities between the rhizospheres of alfalfa and perennial ryegrass/alfalfa mixture in the contaminated soil at week seven. Perennial ryegrass and perennial ryegrass/alfalfa mixture caused the greatest change in the rhizosphere bacterial community as determined by DGGE analysis. We concluded that plants altered the microbial population; these changes were plant-specific and could contribute to degradation of petroleum hydrocarbons in contaminated soil. - Plant-specific changes in microbial populations on roots affect degradation of petroleum hydrocarbons in contaminated soil

  6. In search of a perennial philosophy for behavioral health integration in primary care.

    Science.gov (United States)

    Mauksch, Larry B; Fogarty, Colleen T

    2016-06-01

    The "perennial philosophy," a concept religious scholars have studied for centuries, represents a search for the values, themes, and constructs that transcend individual religions. Can we who develop and disseminate behavioral health integration in primary care step back from individual models to identify our perennial philosophy? If so, what are the components? What does the evidence tell us? What do we need to learn? Four case examples are presented which represent many patients seen by both of us-a family therapist and a family physician-over our combined 55 years of collaborative practice within integrated primary care settings. Can these patients be cared for in a primary care setting? Our experience provides a simple answer-yes. However, providing care for this range of patients requires variability in team configurations, frequency of visits, lengths of relationships, and interventional strategies. Is there a perennial philosophy of how to design and implement the integration of behavioral health in primary care? We think there should be. we highlight a recent publication from the Eugene S. Farley, Jr. Health Policy Center, entitled "Core Competencies For Behavioral Health Providers Working In Primary Care." The authors purposefully transcend models in delineating eight core competencies. Embedded within these competencies are common or perennial factors. These factors may guide our field going forward, helping us avoid "religious" divisions, seek to understand diverse designs, and embrace integration of models to meet the needs of the populations and teams we serve. (PsycINFO Database Record PMID:27270247

  7. Barriers to and drivers of the adpotion of energy crops by Swedish farmers: An empirical approach

    Energy Technology Data Exchange (ETDEWEB)

    Jonsson, Anna C.; Ostwald, Madelene; Asplund, Therese; Wibeck, Victoria (Linkoeping Univ., Linkoeping (Sweden). The Tema Inst., Centre for Climate Science and Policy Research)

    2011-06-15

    Since the Swedish government and the EU intend to encourage farmers to expand energy crop production, knowledge of the factors motivating adoption decisions is vital to policy success. Earlier studies have demonstrated that important barriers to farmer adoption of energy crops include converting from annual to perennial crops and from traditional crops or production systems to new ones. Economic motivations for changing production systems are strong, but factors such as values (e.g., aesthetics), knowledge (e.g., habits and knowledge of production methods), and legal conditions (e.g., cultivation licenses) are crucial for the change to energy crops. This paper helps fill gaps in the literature regarding why farmers decide to keep or change a production system. Based on a series of focus group interviews with Swedish farmers, the paper explores how farmers frame crop change decisions and what factors they consider most important. The main drivers of and barriers to growing energy crops, according to interviewees, are grouped and discussed in relation to four broad groups of motivational factors identified in the literature, i.e., values, legal conditions, knowledge, and economic factors. The paper ends by discussing whether some barriers could be overcome by policy changes at the national and European levels

  8. Impacts of Organic Zero Tillage Systems on Crops, Weeds, and Soil Quality

    Directory of Open Access Journals (Sweden)

    Patrick M. Carr

    2013-07-01

    Full Text Available Organic farming has been identified as promoting soil quality even though tillage is used for weed suppression. Adopting zero tillage and other conservation tillage practices can enhance soil quality in cropping systems where synthetic agri-chemicals are relied on for crop nutrition and weed control. Attempts have been made to eliminate tillage completely when growing several field crops organically. Vegetative mulch produced by killed cover crops in organic zero tillage systems can suppress annual weeds, but large amounts are needed for adequate early season weed control. Established perennial weeds are not controlled by cover crop mulch. Integrated weed management strategies that include other cultural as well as biological and mechanical controls have potential and need to be incorporated into organic zero tillage research efforts. Market crop performance in organic zero tillage systems has been mixed because of weed, nutrient cycling, and other problems that still must be solved. Soil quality benefits have been demonstrated in comparisons between organic conservation tillage and inversion tillage systems, but studies that include zero tillage treatments are lacking. Research is needed which identifies agronomic strategies for optimum market crop performance, acceptable levels of weed suppression, and soil quality benefits following adoption of organic zero tillage.

  9. Irrigation and Maize Cultivation Erode Plant Diversity Within Crops in Mediterranean Dry Cereal Agro-Ecosystems

    Science.gov (United States)

    Fagúndez, Jaime; Olea, Pedro P.; Tejedo, Pablo; Mateo-Tomás, Patricia; Gómez, David

    2016-07-01

    The intensification of agriculture has increased production at the cost of environment and biodiversity worldwide. To increase crop yield in dry cereal systems, vast farmland areas of high conservation value are being converted into irrigation, especially in Mediterranean countries. We analyze the effect of irrigation-driven changes on the farm biota by comparing species diversity, community composition, and species traits of arable plants within crop fields from two contrasting farming systems (dry and irrigated) in Spain. We sampled plant species within 80 fields of dry wheat, irrigated wheat, and maize (only cultivated under irrigation). Wheat crops held higher landscape and per field species richness, and beta diversity than maize. Within the same type of crop, irrigated wheat hosted lower plant diversity than dry wheat at both field and landscape scales. Floristic composition differed between crop types, with higher frequencies of perennials, cosmopolitan, exotic, wind-pollinated and C4 species in maize. Our results suggest that irrigation projects, that transform large areas of dry cereal agro-ecosystems into irrigated crop systems dominated by maize, erode plant diversity. An adequate planning on the type and proportion of crops used in the irrigated agro-ecosystems is needed in order to balance agriculture production and biodiversity conservation.

  10. Irrigation and Maize Cultivation Erode Plant Diversity Within Crops in Mediterranean Dry Cereal Agro-Ecosystems.

    Science.gov (United States)

    Fagúndez, Jaime; Olea, Pedro P; Tejedo, Pablo; Mateo-Tomás, Patricia; Gómez, David

    2016-07-01

    The intensification of agriculture has increased production at the cost of environment and biodiversity worldwide. To increase crop yield in dry cereal systems, vast farmland areas of high conservation value are being converted into irrigation, especially in Mediterranean countries. We analyze the effect of irrigation-driven changes on the farm biota by comparing species diversity, community composition, and species traits of arable plants within crop fields from two contrasting farming systems (dry and irrigated) in Spain. We sampled plant species within 80 fields of dry wheat, irrigated wheat, and maize (only cultivated under irrigation). Wheat crops held higher landscape and per field species richness, and beta diversity than maize. Within the same type of crop, irrigated wheat hosted lower plant diversity than dry wheat at both field and landscape scales. Floristic composition differed between crop types, with higher frequencies of perennials, cosmopolitan, exotic, wind-pollinated and C4 species in maize. Our results suggest that irrigation projects, that transform large areas of dry cereal agro-ecosystems into irrigated crop systems dominated by maize, erode plant diversity. An adequate planning on the type and proportion of crops used in the irrigated agro-ecosystems is needed in order to balance agriculture production and biodiversity conservation.

  11. Comparing net ecosystem carbon dioxide exchange at adjacent commercial bioenergy and conventional cropping systems in Lincolnshire, United Kingdom

    Science.gov (United States)

    Morrison, Ross; Brooks, Milo; Evans, Jonathan; Finch, Jon; Rowe, Rebecca; Rylett, Daniel; McNamara, Niall

    2016-04-01

    The conversion of agricultural land to bioenergy plantations represents one option in the national and global effort to reduce greenhouse gas emissions whilst meeting future energy demand. Despite an increase in the area of (e.g. perennial) bioenergy crops in the United Kingdom and elsewhere, the biophysical and biogeochemical impacts of large scale conversion of arable and other land cover types to bioenergy cropping systems remain poorly characterised and uncertain. Here, the results of four years of eddy covariance (EC) flux measurements of net ecosystem CO2 exchange (NEE) obtained at a commercial farm in Lincolnshire, United Kingdom (UK) are reported. CO2 flux measurements are presented and compared for arable crops (winter wheat, oilseed rape, spring barely) and plantations of the perennial biofuel crops Miscanthus x. giganteus (C4) and short rotation coppice (SRC) willow (Salix sp.,C3). Ecosystem light and temperature response functions were used to analyse and compare temporal trends and spatial variations in NEE across the three land covers. All three crops were net in situ sinks for atmospheric CO2 but were characterised by large temporal and between site variability in NEE. Environmental and biological controls driving the spatial and temporal variations in CO2 exchange processes, as well as the influences of land management, will be analysed and discussed.

  12. Cereal Crops Research Unit

    Data.gov (United States)

    Federal Laboratory Consortium — The mission of the Cereal Crops Research Unit is to 1) conduct basic research to identify and understand the biological processes affecting the growth, development...

  13. Cover crop biomass harvest for bioenergy: implications for crop productivity

    Science.gov (United States)

    Winter cover crops, such as rye (Secale cereale), are usually used in conservation agriculture systems in the Southeast. Typically, the cover crop is terminated two to three weeks before planting the summer crop, with the cover biomass left on the soil surface as a mulch. However, these cover crops ...

  14. Transgenics in crops

    Science.gov (United States)

    Li, Y.; Wu, Y. H.; McAvoy, R.; Duan, H.

    2001-01-01

    With rapid world population growth and declining availability of fresh water and arable land, a new technology is urgently needed to enhance agricultural productivity. Recent discoveries in the field of crop transgenics clearly demonstrate the great potential of this technology for increasing food production and improving food quality while preserving the environment for future generations. In this review, we briefly discuss some of the recent achievements in crop improvement that have been made using gene transfer technology.

  15. Environmental Filtering of Microbial Communities in Agricultural Soil Shifts with Crop Growth.

    Science.gov (United States)

    Hargreaves, Sarah K; Williams, Ryan J; Hofmockel, Kirsten S

    2015-01-01

    Plant and soil properties cooperatively structure soil microbial communities, with implications for ecosystem functioning. However, the extent to which each factor contributes to community structuring is not fully understood. To quantify the influence of plants and soil properties on microbial diversity and composition in an agricultural context, we conducted an experiment within a corn-based annual cropping system and a perennial switchgrass cropping system across three topographic positions. We sequenced barcoded 16S ribosomal RNA genes from whole soil three times throughout a single growing season and across two years in July. To target the belowground effects of plants, we also sampled rhizosphere soil in July. We hypothesized that microbial community α-diversity and composition (β-diversity) would be more sensitive to cropping system effects (annual vs. perennial inputs) than edaphic differences among topographic positions, with greater differences occurring in the rhizosphere compared to whole soil. We found that microbial community composition consistently varied with topographic position, and cropping system and the rhizosphere influenced α-diversity. In July, cropping system and rhizosphere structured a small but specific group of microbes implying a subset of microbial taxa, rather than broad shifts in community composition, may explain previously observed differences in resource cycling between treatments. Using rank abundance analysis, we detected enrichment of Saprospirales and Actinomycetales, including cellulose and chitin degraders, in the rhizosphere soil and enrichment of Nitrospirales, Syntrophobacterales, and MND1 in the whole soil. Overall, these findings support environmental filtering for the soil microbial community first by soil and second by the rhizosphere. Across cropping systems, plants selected for a general rhizosphere community with evidence for plant-specific effects related to time of sampling. PMID:26226508

  16. Environmental Filtering of Microbial Communities in Agricultural Soil Shifts with Crop Growth.

    Directory of Open Access Journals (Sweden)

    Sarah K Hargreaves

    Full Text Available Plant and soil properties cooperatively structure soil microbial communities, with implications for ecosystem functioning. However, the extent to which each factor contributes to community structuring is not fully understood. To quantify the influence of plants and soil properties on microbial diversity and composition in an agricultural context, we conducted an experiment within a corn-based annual cropping system and a perennial switchgrass cropping system across three topographic positions. We sequenced barcoded 16S ribosomal RNA genes from whole soil three times throughout a single growing season and across two years in July. To target the belowground effects of plants, we also sampled rhizosphere soil in July. We hypothesized that microbial community α-diversity and composition (β-diversity would be more sensitive to cropping system effects (annual vs. perennial inputs than edaphic differences among topographic positions, with greater differences occurring in the rhizosphere compared to whole soil. We found that microbial community composition consistently varied with topographic position, and cropping system and the rhizosphere influenced α-diversity. In July, cropping system and rhizosphere structured a small but specific group of microbes implying a subset of microbial taxa, rather than broad shifts in community composition, may explain previously observed differences in resource cycling between treatments. Using rank abundance analysis, we detected enrichment of Saprospirales and Actinomycetales, including cellulose and chitin degraders, in the rhizosphere soil and enrichment of Nitrospirales, Syntrophobacterales, and MND1 in the whole soil. Overall, these findings support environmental filtering for the soil microbial community first by soil and second by the rhizosphere. Across cropping systems, plants selected for a general rhizosphere community with evidence for plant-specific effects related to time of sampling.

  17. Radioactivity in food crops

    International Nuclear Information System (INIS)

    Published levels of radioactivity in food crops from 21 countries and 4 island chains of Oceania are listed. The tabulation includes more than 3000 examples of 100 different crops. Data are arranged alphabetically by food crop and geographical origin. The sampling date, nuclide measured, mean radioactivity, range of radioactivities, sample basis, number of samples analyzed, and bibliographic citation are given for each entry, when available. Analyses were reported most frequently for 137Cs, 40K, 90Sr, 226Ra, 228Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for 241Am, 7Be, 60Co, 55Fe, 3H, 131I, 54Mn, 95Nb, 210Pb, 210Po, 106Ru, 125Sb, 228Th, 232Th, and 95Zr. Based on the reported data it appears that radioactivity from alpha emitters in food crops is usually low, on the order of 0.1 Bq.g-1 (wet weight) or less. Reported values of beta radiation in a given crop generally appear to be several orders of magnitude greater than those of alpha emitters. The most striking aspect of the data is the great range of radioactivity reported for a given nuclide in similar food crops with different geographical origins

  18. Radioactivity in food crops

    Energy Technology Data Exchange (ETDEWEB)

    Drury, J.S.; Baldauf, M.F.; Daniel, E.W.; Fore, C.S.; Uziel, M.S.

    1983-05-01

    Published levels of radioactivity in food crops from 21 countries and 4 island chains of Oceania are listed. The tabulation includes more than 3000 examples of 100 different crops. Data are arranged alphabetically by food crop and geographical origin. The sampling date, nuclide measured, mean radioactivity, range of radioactivities, sample basis, number of samples analyzed, and bibliographic citation are given for each entry, when available. Analyses were reported most frequently for /sup 137/Cs, /sup 40/K, /sup 90/Sr, /sup 226/Ra, /sup 228/Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for /sup 241/Am, /sup 7/Be, /sup 60/Co, /sup 55/Fe, /sup 3/H, /sup 131/I, /sup 54/Mn, /sup 95/Nb, /sup 210/Pb, /sup 210/Po, /sup 106/Ru, /sup 125/Sb, /sup 228/Th, /sup 232/Th, and /sup 95/Zr. Based on the reported data it appears that radioactivity from alpha emitters in food crops is usually low, on the order of 0.1 Bq.g/sup -1/ (wet weight) or less. Reported values of beta radiation in a given crop generally appear to be several orders of magnitude greater than those of alpha emitters. The most striking aspect of the data is the great range of radioactivity reported for a given nuclide in similar food crops with different geographical origins.

  19. Teale California shoreline

    Data.gov (United States)

    California Department of Resources — California Spatial Information System (CaSIL) is a project designed to improve access to geo-spatial and geo-spatial related data information throughout the state...

  20. California Condor Critical Habitat

    Data.gov (United States)

    California Department of Resources — These Data identify (in general) the areas where critical habitat for the California Condor occur. Critical habitat for the species consists of the following 10...

  1. Biofuel cropping system impacts on soil C, microbial communities and N2O emissions

    Science.gov (United States)

    McGowan, Andrew R.

    Substitution of cellulosic biofuel in place of gasoline or diesel could reduce greenhouse gas (GHG) emissions from transportation. However, emissions of nitrous oxide (N2O) and changes in soil organic carbon (SOC) could have a large impact on the GHG balance of cellulosic biofuel, thus there is a need to quantify these responses in cellulosic biofuel crops. The objectives of this study were to: (i) measure changes in yield, SOC and microbial communities in potential cellulosic biofuel cropping systems (ii) measure and characterize the temporal variation in N2O emissions from these systems (iii) characterize the yield and N2O response of switchgrass to N fertilizer and to estimate the costs of production. Sweet sorghum, photoperiod-sensitive sorghum, and miscanthus yielded the highest aboveground biomass (20-32 Mg ha-1). The perennial grasses sequestered SOC over 4 yrs, while SOC stocks did not change in the annual crops. Root stocks were 4-8 times higher in the perennial crops, suggesting greater belowground C inputs. Arbuscular mycorrhizal fungi (AMF) abundance and aggregate mean weight diameter were higher in the perennials. No consistent significant differences were found in N2O emissions between crops, though miscanthus tended to have the lowest emissions. Most N2O was emitted during large events of short duration (1-3 days) that occurred after high rainfall events with high soil NO3-. There was a weak relationship between IPCC Tier 1 N2O estimates and measured emissions, and the IPCC method tended to underestimate emissions. The response of N2O to N rate was nonlinear in 2 of 3 years. Fertilizer induced emission factor (EF) increased from 0.7% at 50 kg N ha-1 to 2.6% at 150 kg N ha-1. Switchgrass yields increased with N inputs up to 100-150 kg N ha-1, but the critical N level for maximum yields decreased each year, suggesting N was being applied in excess at higher N rates. Yield-scaled costs of production were minimized at 100 kg N ha-1 ($70.91 Mg-1

  2. Exogenous Classic Phytohormones Have Limited Regulatory Effects on Fructan and Primary Carbohydrate Metabolism in Perennial Ryegrass (Lolium perenne L.).

    Science.gov (United States)

    Gasperl, Anna; Morvan-Bertrand, Annette; Prud'homme, Marie-Pascale; van der Graaff, Eric; Roitsch, Thomas

    2015-01-01

    Fructans are polymers of fructose and one of the main constituents of water-soluble carbohydrates in forage grasses and cereal crops of temperate climates. Fructans are involved in cold and drought resistance, regrowth following defoliation and early spring growth, seed filling, have beneficial effects on human health and are used for industrial processes. Perennial ryegrass (Lolium perenne L.) serves as model species to study fructan metabolism. Fructan metabolism is under the control of both synthesis by fructosyltransferases (FTs) and breakdown through fructan exohydrolases (FEHs). The accumulation of fructans can be triggered by high sucrose levels and abiotic stress conditions such as drought and cold stress. However, detailed studies on the mechanisms involved in the regulation of fructan metabolism are scarce. Since different phytohormones, especially abscisic acid (ABA), are known to play an important role in abiotic stress responses, the possible short term regulation of the enzymes involved in fructan metabolism by the five classical phytohormones was investigated. Therefore, the activities of enzymes involved in fructan synthesis and breakdown, the expression levels for the corresponding genes and levels for water-soluble carbohydrates were determined following pulse treatments with ABA, auxin (AUX), ethylene (ET), gibberellic acid (GA), or kinetin (KIN). The most pronounced fast effects were a transient increase of FT activities by AUX, KIN, ABA, and ET, while minor effects were evident for 1-FEH activity with an increased activity in response to KIN and a decrease by GA. Fructan and sucrose levels were not affected. This observed discrepancy demonstrates the importance of determining enzyme activities to obtain insight into the physiological traits and ultimately the plant phenotype. The comparative analyses of activities for seven key enzymes of primary carbohydrate metabolism revealed no co-regulation between enzymes of the fructan and sucrose pool

  3. Exogenous classic phytohormones have limited regulatory effects on fructan and primary carbohydrate metabolism in perennial ryegrass (Lolium perenne L.

    Directory of Open Access Journals (Sweden)

    Anna eGasperl

    2016-01-01

    Full Text Available Fructans are polymers of fructose and one of the main constituents of water-soluble carbohydrates in forage grasses and cereal crops of temperate climates. Fructans are involved in cold and drought resistance, regrowth following defoliation and early spring growth, seed filling, have beneficial effects on human health and are used for industrial processes. Perennial ryegrass (Lolium perenne L. serves as model species to study fructan metabolism. Fructan metabolism is under the control of both synthesis by fructosyltransferases (FTs and breakdown through fructan exohydrolases (FEHs. The accumulation of fructans can be triggered by high sucrose levels and abiotic stress conditions such as drought and cold stress. However, detailed studies on the mechanisms involved in the regulation of fructan metabolism are scarce. Since different phytohormones, especially abscisic acid (ABA, are known to play an important role in abiotic stress responses, the possible short term regulation of the enzymes involved in fructan metabolism by the five classical phytohormones was investigated. Therefore, the activities of enzymes involved in fructan synthesis and breakdown, the expression levels for the corresponding genes and levels for water-soluble carbohydrates were determined following pulse treatments with ABA, auxin (AUX, ethylene (ET, gibberellic acid (GA or kinetin (KIN. The most pronounced fast effects were a transient increase of FT activities by AUX, KIN, ABA and ET, while minor effects were evident for 1-FEH activity with an increased activity in response to KIN and a decrease by GA. Fructan and sucrose levels were not affected. This observed discrepancy demonstrates the importance of determining enzyme activities to obtain insight into the physiological traits and ultimately the plant phenotype. The comparative analyses of activities for seven key enzymes of primary carbohydrate metabolism revealed no co-regulation between enzymes of the fructan and

  4. Drought responsive gene expression regulatory divergence between upland and lowland ecotypes of a perennial C4 grass.

    Science.gov (United States)

    Lovell, John T; Schwartz, Scott; Lowry, David B; Shakirov, Eugene V; Bonnette, Jason E; Weng, Xiaoyu; Wang, Mei; Johnson, Jenifer; Sreedasyam, Avinash; Plott, Christopher; Jenkins, Jerry; Schmutz, Jeremy; Juenger, Thomas E

    2016-04-01

    Climatic adaptation is an example of a genotype-by-environment interaction (G×E) of fitness. Selection upon gene expression regulatory variation can contribute to adaptive phenotypic diversity; however, surprisingly few studies have examined how genome-wide patterns of gene expression G×E are manifested in response to environmental stress and other selective agents that cause climatic adaptation. Here, we characterize drought-responsive expression divergence between upland (drought-adapted) and lowland (mesic) ecotypes of the perennial C4 grass,Panicum hallii, in natural field conditions. Overall, we find that cis-regulatory elements contributed to gene expression divergence across 47% of genes, 7.2% of which exhibit drought-responsive G×E. While less well-represented, we observe 1294 genes (7.8%) with transeffects.Trans-by-environment interactions are weaker and much less common than cis G×E, occurring in only 0.7% oft rans-regulated genes. Finally, gene expression heterosis is highly enriched in expression phenotypes with significant G×E. As such, modes of inheritance that drive heterosis, such as dominance or overdominance, may be common among G×E genes. Interestingly, motifs specific to drought-responsive transcription factors are highly enriched in the promoters of genes exhibiting G×E and transregulation, indicating that expression G×E and heterosis may result from the evolution of transcription factors or their binding sites.P. hallii serves as the genomic model for its close relative and emerging biofuel crop, switchgrass (Panicum virgatum). Accordingly, the results here not only aid in the discovery of the genetic mechanisms that underlie local adaptation but also provide a foundation to improve switchgrass yield under water-limited conditions. PMID:26953271

  5. Cover crops and N credits

    Science.gov (United States)

    Cover crops often provide many short- and long-term benefits to cropping systems. Legume cover crops can significantly reduce the N fertilizer requirement of non-legume cash crops that follow. The objectives of this presentation were to: I) educate stakeholders about the potential benefits of cover ...

  6. Biotechnology: herbicide-resistant crops

    Science.gov (United States)

    Transgenic, herbicide-resistant (HR) crops are planted on about 80% of the land covered by transgenic crops. More than 90% of HR crios are glyphosate-resistant (GR) crops, the others being resistant to glufosinate. The wide-scale adoption of HR crops, largely for economic reasons, has been the mos...

  7. Potential phytoextraction and phytostabilization of perennial peanut on copper-contaminated vineyard soils and copper mining waste.

    Science.gov (United States)

    Andreazza, Robson; Bortolon, Leandro; Pieniz, Simone; Giacometti, Marcelo; Roehrs, Dione D; Lambais, Mácio R; Camargo, Flávio A O

    2011-12-01

    This study sought to evaluate the potential of perennial peanut (Arachis pintoi) for copper phytoremediation in vineyard soils (Inceptisol and Mollisol) contaminated with copper and copper mining waste. Our results showed high phytomass production of perennial peanut in both vineyard soils. Macronutrient uptakes were not negatively affected by perennial peanut cultivated in all contaminated soils. Plants cultivated in Mollisol showed high copper concentrations in the roots and shoots of 475 and 52 mg kg(-1), respectively. Perennial peanut plants showed low translocation factor values for Cu, although these plants showed high bioaccumulation factor (BCF) for both vineyard soils, Inceptisol and Mollisol, with BCF values of 3.83 and 3.24, respectively, being characterized as a copper hyperaccumulator plant in these soils. Copper phytoextraction from Inceptisol soil was the highest for both roots and entire plant biomass, with more than 800 mg kg(-1) of copper in whole plant. The highest potential copper phytoextraction by perennial peanut was in Inceptisol soil with copper removal of 2,500 g ha(-1). Also, perennial peanut showed high potential for copper phytoremoval in copper mining waste and Mollisol with 1,700 and 1,500 g of copper per hectare, respectively. In addition, perennial peanuts characterized high potential for phytoextraction and phytostabilization of copper in vineyard soils and copper mining waste. PMID:21286847

  8. Nitrous oxide, carbon dioxide and methane emissions from irrigated cropping systems as influenced by legumes, manure and fertilizer

    Energy Technology Data Exchange (ETDEWEB)

    Ellert, B.H.; Janzen, H.H. [Agriculture and Agri-Food Canada, Lethbridge, AB (Canada)

    2008-04-15

    Irrigated crops in Alberta require higher inputs of nitrogen (N) than rainfed crops. The aim of the study was to determine emissions of nitrous oxide (N{sub 2}O) from the soils of irrigated cropping systems that used inorganic fertilizer N at a site in Alberta. The study measured carbon dioxide (CO{sub 2}) and methane (CH{sub 4}) levels in order to determine net greenhouse gas (GHG) emissions. The exchange of gases between the atmosphere and soil in selected treatments was measured in order to compare the effects of contrasting N inputs. Fluxes were measured bi-weekly from spring 2001 to spring 2004. The time period included annual and perennial legume crops; the termination of a perennial forage crop; manure application; and 2 growing seasons of test crops. Soil surface fluxes were measured using PVC chambers equipped with thermocouples. Gas samples were measured using gas chromatography. A linear least squares method was used to calculate gas concentrations. Results showed that soil CO{sub 2} and N{sub 2}O production rates were intertwined after legume production or manure application, but decoupled during early spring bursts of N{sub 2}O production. Higher soil CO{sub 2} emissions with alfalfa and manure-amended soils suggested that soil oxygen consumption during high CO{sub 2} emission periods may promote N{sub 2}O emissions. Appreciable proportions of N{sub 2}O were emitted outside the growing season. Results suggested that N{sub 2}O leakage is an inevitable hazard of crop production. The study highlighted the importance of understanding and quantifying N{sub 2}O emissions from intensive cropping systems. 22 refs., 4 tabs., 6 figs.

  9. The effect of glyphosate, paraquat and paclobutrazol on lolitrem B levels in endophyte-infected perennial ryegrass.

    Science.gov (United States)

    Prestidge, R A; Sprosen, J M

    1995-08-01

    Two herbicides (glyphosate and paraquat) and a plant growth regulator (paclobutrazol) were applied to endophyteinfected (Acremonium lolii) perennial ryegrass swards. Subsamples of these swards were then chemically analysed at intervals up to 28 days later for lolitrem B, the compound responsible for perennial ryegrass staggers in domestic livestock. Glyphosate and paclobutrazol had no effect on lolitrem B concentrations. Paraquat applications decreased lolitrem B concentrations in the herbage. Because none of the chemicals tested increased the concentration of lolitrem B in the herbage, they are unlikely to be directly implicated in perennial ryegrass staggers in grazing animals.

  10. N2O Emission from energy crop fields

    International Nuclear Information System (INIS)

    The interest in N2O emissions from soils with energy crops is a results of its properties as a greenhouse gas, since the global warming potential of N2O per unit mass is about 320 times greater than CO2. The contribution of N2O from the soil to the atmosphere may increase due to agricultural management. Consequently, large N2O emissions can lower the reduction of the greenhouse effect achieved by the substitution of fossil fuels by energy crops. For this reason it is crucial to find the crops for combustion with the lowest potential for emission of N2O from the soil per produced energy unit. The aims of this study were to assess the annual N2O flux from a Miscanthus 'Giganteus' (M. 'Giganteus') and winter rye (Secale cereale) field, and to investigate the factors affecting the N2O emission. To obtain these aims a method was developed for measurements in tall crops. The thesis contains a literature review on the N2O emission from the soils, a section with development of the technique for N2O flux measurements, and an experimental section. Finally, the thesis contains a section where the results are discussed in relation to the use of energy crops. In all the filed studies, the N2O emission was measured by using a new developed closed-chamber technique. The main advantages of the chamber method were the ability to contain growing plants up to a height of 3 m, and the relatively large area (2X2m) covered by each other. Soils with annual and perennial crops can be expected to emit less then 3 kg N2O ha-1 yr-1. This amount corresponds to 960 kg CO2 ha-1 yr-1 compared to a total CO2 reduction of 10 to 19 tons CO2 ha-1 yr-1 using the energy crops as substitution for fossil fuels. An efficient way to reduce the N2O emission is to exclude use of fertiliser but this also reduces the dry matter yield and consequently also the CO2 reduction per unit dry matter. Following the guidelines for good agricultural practice concerning the efficiency of the nitrogen usage, it seems

  11. Greenhouse gas fluxes during growth of different bioenergy crops

    Science.gov (United States)

    Walter, K.; Don, A.; Flessa, H.

    2012-04-01

    gas budget of the anlysed crops. Emissions related to management activities and during fertilizer production have to be taken into account. Total emissions were related to the net energy yield of the different crops. Our first results indicate that perennial crops have the potential to reduce greenhouse gas emissions from bioenergy crop production as compared to annual crops due to its lower fertilizer demand.

  12. Global Simulation of Bioenergy Crop Productivity: Analytical Framework and Case Study for Switchgrass

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Shujiang [ORNL; Kline, Keith L [ORNL; Nair, S. Surendran [University of Tennessee, Knoxville (UTK); Nichols, Dr Jeff A [ORNL; Post, Wilfred M [ORNL; Brandt, Craig C [ORNL; Wullschleger, Stan D [ORNL; Wei, Yaxing [ORNL; Singh, Nagendra [ORNL

    2013-01-01

    A global energy crop productivity model that provides geospatially explicit quantitative details on biomass potential and factors affecting sustainability would be useful, but does not exist now. This study describes a modeling platform capable of meeting many challenges associated with global-scale agro-ecosystem modeling. We designed an analytical framework for bioenergy crops consisting of six major components: (i) standardized natural resources datasets, (ii) global field-trial data and crop management practices, (iii) simulation units and management scenarios, (iv) model calibration and validation, (v) high-performance computing (HPC) simulation, and (vi) simulation output processing and analysis. The HPC-Environmental Policy Integrated Climate (HPC-EPIC) model simulated a perennial bioenergy crop, switchgrass (Panicum virgatum L.), estimating feedstock production potentials and effects across the globe. This modeling platform can assess soil C sequestration, net greenhouse gas (GHG) emissions, nonpoint source pollution (e.g., nutrient and pesticide loss), and energy exchange with the atmosphere. It can be expanded to include additional bioenergy crops (e.g., miscanthus, energy cane, and agave) and food crops under different management scenarios. The platform and switchgrass field-trial dataset are available to support global analysis of biomass feedstock production potential and corresponding metrics of sustainability.

  13. Traits to ecosystems: The ecological sustainability challenge when developing future energy crops

    Directory of Open Access Journals (Sweden)

    Martin eWeih

    2014-05-01

    Full Text Available Today we are undertaking great efforts to improve biomass production and quality traits of energy crops. Major motivation for developing those crops is based on environmental and ecological sustainability considerations, which however often are de-coupled from the trait-based crop improvement programs. It is now time to develop appropriate methods to link crop traits to production system characteristics set by the plant and the biotic communities influencing it; and to the ecosystem processes affecting ecological sustainability. The relevant ecosystem processes involve the net productivity in terms of biomass and energy yields, the depletion of energy-demanding resources (e.g. nitrogen, N, the carbon dynamics in soil and atmosphere, and the resilience and temporal stability of the production system. In a case study, we compared aspects of N use efficiency in various varieties of an annual (spring wheat and perennial (Salix energy crop grown under two nutrient regimes in Sweden. For example, we found considerable variation among crops, varieties and nutrient regimes in the energy yield per plant-internal N (MJ g-1 yr-1, which would result in different N resource depletion per unit energy produced.

  14. Growth Rings of Roots in Perennial Forbs in Duolun Grassland, Inner Mongolia, China

    Institute of Scientific and Technical Information of China (English)

    Yong-Bo Liu; Qi-Bin Zhang

    2007-01-01

    Annual growth rings of roots in perennial forbs have been used in studies of climate change and the ecology of grasslands. However, little has been done in this aspect of research in China. In this study, we report the characteristics of growth rings in the main roots of 13 herb species sampled in Duolun of the Inner Mongolia grassland in northern China. The results show that around two thirds of the species possess clearly demarcated annual rings in the root xylem. Some species of the same genera show different patterns in anatomical structure of the root xylem. Standardized annual ring widths of three species, Potentilla anserine L., Cymbaria dahurica L. and Lespedeza daurica (Laxm.) Schindl., show a common linear trend, indicating a continued favorable growth condition in the sampling sites. Our results provide evidence that growth rings in roots of some perennial forbs in the Inner Mongolia grassland can serve as a new and useful indicator of past changes in the grassland environment.

  15. A proteomics sample preparation method for mature, recalcitrant leaves of perennial plants.

    Directory of Open Access Journals (Sweden)

    Deng Gang

    Full Text Available Sample preparation is key to the success of proteomics studies. In the present study, two sample preparation methods were tested for their suitability on the mature, recalcitrant leaves of six representative perennial plants (grape, plum, pear, peach, orange, and ramie. An improved sample preparation method was obtained: Tris and Triton X-100 were added together instead of CHAPS to the lysis buffer, and a 20% TCA-water solution and 100% precooled acetone were added after the protein extraction for the further purification of protein. This method effectively eliminates nonprotein impurities and obtains a clear two-dimensional gel electrophoresis array. The method facilitates the separation of high-molecular-weight proteins and increases the resolution of low-abundance proteins. This method provides a widely applicable and economically feasible technology for the proteomic study of the mature, recalcitrant leaves of perennial plants.

  16. Fructan metabolism and changes in fructan composition during cold acclimation in perennial ryegrass

    DEFF Research Database (Denmark)

    Abeynayake, Shamila; Etzerodt, Thomas; Jonavičienė, Kristina;

    2015-01-01

    biomass (top) and the roots, and the transcription of candidate genes involved in fructan metabolism during cold acclimation in perennial ryegrass variety ‘Veyo’ and ecotype ‘Falster’ from distinct geographical origins. We observed changes in fructan composition and induction of low-DP fructans......Perennial ryegrass (Lolium perenne L.) produces high levels of fructans as a mixture of oligomers with different degrees of polymerization (DP). The present study describes the analysis of the compositional changes in the full spectrum of fructan oligomers, fructan distribution between above ground....... The ecotype ‘Falster’, adapted to cold climates, increased total fructan content and produced more fructans (DP˃7) in the roots than the variety ‘Veyo’, adapted to warmer climates suggesting that accumulation of fructans in roots, especially the high-DP fructans as an adaptive trait for plant recovery after...

  17. QTL analysis of crown rust resistance in perennial ryegrass under conditions of natural and artificial infection

    DEFF Research Database (Denmark)

    Schejbel, Britt; Jensen, Louise Friis Bach; Xing, Yongzhong;

    2007-01-01

    Crown rust is an economically devastating disease of perennial ryegrass. Both artificial crown rust inoculations, with the possibility of several selection cycles in one year, as well as marker-assisted selection can be used for more efficient breeding of new resistant cultivars. The objective...... of this study was to map quantitative trait loci (QTL) for response to crown rust infection in perennial ryegrass. In order to identify relevant markers for response to crown rust infection, QTL mapping was performed on a ryegrass mapping population which was evaluated for resistance in the field for two years...... as well as by artificial pathogen inoculations using a detached leaf assessment. The broad sense heritability values for the field, detached leaf and combined assays were 0.42, 0.56, and 0.64, respectively, indicating a good potential for selection for crown rust resistance. A total of six QTLs were...

  18. High-Throughput SNP Discovery And Genetic Mapping In Perennial Ryegrass

    DEFF Research Database (Denmark)

    Asp, Torben; Studer, Bruno; Lübberstedt, Thomas

    Gene-associated single nucleotide polymorphisms (SNPs) are of major interest for genome analysis and breeding applications in the key grassland species perennial ryegrass. High-throughput 454 Titanium transcriptome sequencing was performed on two genotypes, which previously have been used...... to establish the VrnA F2 mapping population. The sequences were assembled and used for in-silico SNP discovery. SNPs supported by a minimum number of eight reads, within candidate genes for important agronomic traits, were selected for Illumina GoldenGate genotyping and used to map 768 expressed genes...... in the VrnA mapping population. Here we report on large-scale SNP discovery, and the construction of a genetic map enabling QTL fine mapping, map-based cloning, and comparative genomics in perennial ryegrass....

  19. County-Level Crop Yield Prediction Using Remote Sensing Data

    Science.gov (United States)

    Wagstaff, K. L.; Roper, A.; Lane, T.

    2007-12-01

    Early estimates of crop yield, particularly at a fine scale, can inform precision agriculture efforts. The USDA National Agricultural Statistics Service (NASS) currently provides estimates of yield on a monthly basis for each state. These estimates are based on phone interviews with farmers and in-situ examination of randomly selected plots. We seek to provide predictions at a much higher spatial resolution, on a more frequent basis, using remote sensing observations. We use publicly available data from the MODIS (Moderate Resolution Imaging Spectroradiometer) instruments on the Aqua and Terra spacecraft. These observations have a spatial resolution of 250 m and consist of two spectral bands (red and infra-red) with a repeat period of 8 days. As part of the HARVIST (Heterogeneous Agricultural Research Via Interactive, Scalable Technology) project, we have created statistical crop yield models using historical MODIS data combined with the per-county yield reported by the USDA at the end of the growing season. In our approach, we analyze 100 randomly selected historical pixels from each county to generate a yield prediction for the county as a whole. We construct a time series for each pixel that consists of its NDVI (Normalized Difference Vegetation Index) value observed during each 8-day time period to date. We then cluster all pixels together to identify groups of distinct elements (different crops, bodies of water, urban areas, desert, etc.) and create a regression model for each one. For each crop of interest, the model that best predicts that crop's historical yield is selected. These models can then be applied to data from subsequent years to generate predictions for the future. We applied this approach to data from California and Kansas for corn and wheat. We found that, in general, the yield prediction error decreased as the harvest time approached. In California, distinctly different models were selected to predict corn and wheat, permitting specialization

  20. Ecological and Evolutionary Consequences of Herbivory in the Perennial Herb Lythrum salicaria

    OpenAIRE

    Lehndal, Lina

    2015-01-01

    In this thesis, I combined field, common-garden and greenhouse experiments to examine the ecological and evolutionary consequences of plant-herbivore interactions in the perennial herb Lythrum salicaria. More specifically I examined (1) whether resistance and tolerance to damage from herbivores vary with latitude and are positively related to the intensity of herbivory in natural populations, (2) whether effects of herbivory on plant fitness vary with latitude, (3) whether populations are loc...

  1. Effect of Inhalation of Aromatherapy Oil on Patients with Perennial Allergic Rhinitis: A Randomized Controlled Trial

    OpenAIRE

    Seo Yeon Choi; Kyungsook Park

    2016-01-01

    This study aimed to investigate the effects of aromatherapy oil inhalation on symptoms, quality of life, sleep quality, and fatigue level among adults with perennial allergic rhinitis (PAR). Fifty-four men and women aged between 20 and 60 were randomized to inhale aromatherapy oil containing essential oil from sandalwood, geranium, and Ravensara or almond oil (the placebo) for 5 minutes twice daily for 7 days. PAR symptoms determined by Total Nasal Symptom Score (TNSS), the Rhinoconjunctiviti...

  2. A transcriptome map of perennial ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Studer, Bruno; Byrne, Stephen; Nielsen, Rasmus Ory;

    2012-01-01

    . Conclusions Here, we present an efficient approach of using next generation sequencing (NGS) data for SNP discovery, and the successful design of a 768-plex Illumina GoldenGate genotyping assay in a complex genome. The ryegrass SNPs along with the corresponding transcribed sequences represent a milestone...... to QTL, functional genomics and the integration of genetic and physical maps in perennial ryegrass, one of the most important temperate grassland species....

  3. Life-history variation in contrasting habitats: flowering decisions in a clonal perennial herb (Veratrum album)

    OpenAIRE

    Hesse, Elze; Rees, Mark; Müller-Schärer, Heinz

    2008-01-01

    Quantifying intraspecific demographic variation provides a powerful tool for exploring the diversity and evolution of life histories. We investigate how habitat-specific demographic variation and the production of multiple offspring types affect the population dynamics and evolution of delayed reproduction in a clonal perennial herb with monocarpic ramets (white hellebore). In this species, flowering ramets produce both seeds and asexual offspring. Data on ramet demography are used to paramet...

  4. De novo assembly of the perennial ryegrass transcriptome using an RNA-Seq strategy.

    Directory of Open Access Journals (Sweden)

    Jacqueline D Farrell

    Full Text Available Perennial ryegrass is a highly heterozygous outbreeding grass species used for turf and forage production. Heterozygosity can affect de-Bruijn graph assembly making de novo transcriptome assembly of species such as perennial ryegrass challenging. Creating a reference transcriptome from a homozygous perennial ryegrass genotype can circumvent the challenge of heterozygosity. The goals of this study were to perform RNA-sequencing on multiple tissues from a highly inbred genotype to develop a reference transcriptome. This was complemented with RNA-sequencing of a highly heterozygous genotype for SNP calling.De novo transcriptome assembly of the inbred genotype created 185,833 transcripts with an average length of 830 base pairs. Within the inbred reference transcriptome 78,560 predicted open reading frames were found of which 24,434 were predicted as complete. Functional annotation found 50,890 transcripts with a BLASTp hit from the Swiss-Prot non-redundant database, 58,941 transcripts with a Pfam protein domain and 1,151 transcripts encoding putative secreted peptides. To evaluate the reference transcriptome we targeted the high-affinity K+ transporter gene family and found multiple orthologs. Using the longest unique open reading frames as the reference sequence, 64,242 single nucleotide polymorphisms were found. One thousand sixty one open reading frames from the inbred genotype contained heterozygous sites, confirming the high degree of homozygosity.Our study has developed an annotated, comprehensive transcriptome reference for perennial ryegrass that can aid in determining genetic variation, expression analysis, genome annotation, and gene mapping.

  5. Drought Effects on Agricultural Yield: Comparison Across Regions and Crop Types

    Science.gov (United States)

    Daryanto, S.; Wang, L.; Jacinthe, P. A.

    2014-12-01

    Global agricultural production is dominated by rainfed agriculture, and is therefore prone to disruption from climate extreme weathers. These uncertainties become more problematic when considering the projection of increased drought frequency suggested by several climate models for various world regions. Curiously, few regional analyses of drought impact of food production have been attempted. We collated and analyzed data from the last 25 years to disentangle the effects of drought (i.e. timing, intensity and duration) on agricultural production in different eco-regions and with varying crop types. Our preliminary results suggested greater yield reduction in annual (-21.5%) than perennial plants (-16%), in C4 (-21%) compared to C3 crops (-17%), and when drought occurred during generative (i.e. flowering until maturity; -16.5%) than vegetative stage (-15.5%). Although drought caused similar amounts of yield reduction in both tropical and subtropical regions (i.e. -17%), it carries a greater food security risk in the tropics due to inherently low productivity (i.e. less than half than in the subtropical regions). Consequently, cultivating drought-resistant C3 perennial plants (e.g. sweet potato and cassava) in the tropics could prove a viable adaptive strategy to mitigate the effects of climate variability. In addition, these crops have limited input requirements, are well adapted to nutrient-poor Oxisols and Ultisols of the tropics, and generally outyield cereal crops in the region. Our analysis is ongoing and needs to take into account agronomic traits (e.g. water requirement), as well as the energy and nutritional values (e.g. protein, minerals) of alternative crops. Our results could inform the selection and development of new cultivars for the drought-prone regions of the world.

  6. Fast-cycling unit of root turnover in perennial herbaceous plants in a cold temperate ecosystem

    Science.gov (United States)

    Sun, Kai; Luke McCormack, M.; Li, Le; Ma, Zeqing; Guo, Dali

    2016-01-01

    Roots of perennial plants have both persistent portion and fast-cycling units represented by different levels of branching. In woody species, the distal nonwoody branch orders as a unit are born and die together relatively rapidly (within 1–2 years). However, whether the fast-cycling units also exist in perennial herbs is unknown. We monitored root demography of seven perennial herbs over two years in a cold temperate ecosystem and we classified the largest roots on the root collar or rhizome as basal roots, and associated finer laterals as secondary, tertiary and quaternary roots. Parallel to woody plants in which distal root orders form a fast-cycling module, basal root and its finer laterals also represent a fast-cycling module in herbaceous plants. Within this module, basal roots had a lifespan of 0.5–2 years and represented 62–87% of total root biomass, thus dominating annual root turnover (60%–81% of the total). Moreover, root traits including root length, tissue density, and biomass were useful predictors of root lifespan. We conclude that both herbaceous and woody plants have fast-cycling modular units and future studies identifying the fast-cycling module across plant species should allow better understanding of how root construction and turnover are linked to whole-plant strategies.

  7. Candidate gene association mapping for winter survival and spring regrowth in perennial ryegrass.

    Science.gov (United States)

    Yu, Xiaoqing; Pijut, Paula M; Byrne, Stephen; Asp, Torben; Bai, Guihua; Jiang, Yiwei

    2015-06-01

    Perennial ryegrass (Lolium perenne L.) is a widely cultivated cool-season grass species because of its high quality for forage and turf. Susceptibility to freezing damage limits its further use in temperate zones. The objective of this study was to identify candidate genes significantly associated with winter survival and spring regrowth in a global collection of 192 perennial ryegrass accessions. Significant differences in winter survival (WS), percentage of canopy green cover (CGC), chlorophyll index (Chl), and normalized difference vegetation index (NDVI) were found among accessions. After controlling population structure, LpLEA3 encoding a late embryogenesis abundant group 3 protein and LpCAT encoding a catalase were associated with CGC and Chl, while LpMnSOD encoding a magnesium superoxide dismutase and LpChl Cu-ZnSOD encoding a chlorophyll copper-zinc superoxide dismutase were associated with NDVI or Chl. Significant association was also discovered between C-repeat binding factor LpCBF1b and WS. Three sequence variations identified in LpCAT, LpMnSOD, and LpChl Cu-ZnSOD were synonymous substitutions, whereas one pair of adjacent single nucleotide polymorphisms (SNPs) in LpLEA3 and one SNP in LpCBF1b resulted in amino acid change. The results demonstrated that allelic variation in LpLEA3 and LpCBF1b was closely related to winter survival and spring regrowth in perennial ryegrass. PMID:25900564

  8. Population structure, genetic variation and linkage disequilibrium in perennial ryegrass populations divergently selected for freezing tolerance

    Directory of Open Access Journals (Sweden)

    Mallikarjuna Rao eKovi

    2015-11-01

    Full Text Available Low temperature is one of the abiotic stresses seriously affecting the growth of perennial ryegrass (Lolium perenne L. Understanding the genetic control of freezing tolerance would aid in the development of cultivars of perennial ryegrass with improved adaptation to frost. A total number of 80 individuals (24 of High frost [HF]; 29 of Low frost [LF] and 27 of Unselected [US] from the second generation of the two divergently selected populations and an unselected control population were genotyped using 278 genome-wide SNPs derived from Lolium perenne L. transcriptome sequence. Our studies showed that the HF and LF populations are very divergent after selection for freezing tolerance, whereas the HF and US populations are more similar. Linkage disequilibrium (LD decay varied across the seven chromosomes and the conspicuous pattern of LD between the HF and LF population confirmed their divergence in freezing tolerance. Furthermore, two Fst outlier methods; finite island model (fdist by LOSITAN and hierarchical structure model using ARLEQUIN detected six loci under directional selection. These outlier loci are most probably linked to genes involved in freezing tolerance, cold adaptation and abiotic stress and might be the potential marker resources for breeding perennial ryegrass cultivars with improved freezing tolerance.

  9. An evaluation of physical and biogeochemical processes regulating perennial suboxic conditions in the water column of the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.

    that oxygen minimum zone (OMZ) in the Arabian Sea is regulated largely by physical processes in association with biogeochemical cycling of oxygen. This results in perennial suboxic conditions in the water column with no significant seasonal variability...

  10. Mixed crop-livestock production systems of smallholder farmers in sub-humid and semi-arid areas of Zambia

    International Nuclear Information System (INIS)

    Livestock production activities among small-scale farmers of semi-arid (Agro-ecological zone 1) and sub-humid (Agro-ecological zone 2) areas of Zambia are integrated with crop production activities in what is termed as crop/livestock farming system. This is a closed system in which production of one enterprise depends on the other. In Zambia, crop production depends on draught animals for tillage of cropping area, animal manure for fertilisation of crops while livestock depend on crop residues for dry season feeding. Good quality grass is generally available in adequate amounts to support reasonable level of livestock productivity during the rainy season. But livestock rely on low quantity and poor quality, highly fibrous perennial grass from veld and fibrous crop residues during the dry season. These resources are inadequate to support optimum livestock productivity activities. Poor nutrition results in low rates of reproduction and production as well as increased susceptibility to diseases. With the increasing human population cropping land is expanding, leading to increased production of crop residues. This has however, reduced the grazing land available for ruminant production. In Zambia large quantities of crop residues (stovers, husks and straws, legume tops and hulls, sugar cane tops, cassava leaves, potato vines, etc.) are left in the field where they are wasted each year because small-scale farmers lack the knowledge on how best to use them. There is a need to find ways to reverse this situation by adapting known and workable technologies to local conditions and by introducing new approaches for improving the use of crop residues and poor quality fibrous feeds. Efforts should also be made to enlarge feed resource base. The technologies should be simple and effective. In the presence of a dynamic market system, livestock production in a crop/livestock system could be intensified and made profitable for small-scale farmers. (author)

  11. 78 FR 17606 - Common Crop Insurance Regulations; Arizona-California Citrus Crop Insurance Provisions

    Science.gov (United States)

    2013-03-22

    ... trees are ``top-worked.'' Since trees that have been topworked will produce little or no fruit for several years after grafting, it is not appropriate to insure the fruit these trees produce until the.... See the Notice related to 7 CFR part 3015, subpart V, published at 48 FR 29115, June 24,...

  12. Evaluation of the ECOSSE model for simulating soil organic carbon under Miscanthus and short rotation coppice-willow crops in Britain

    OpenAIRE

    Dondini, Marta; Richards, Mark; Pogson, Mark; Jones, Edwards O.; Rowe, Rebecca L.; Keith, Aidan M.; Niall P McNamara; Smith, Joanne U.; Smith, Pete

    2016-01-01

    In this paper, we focus on the impact on soil organic carbon (SOC) of two dedicated energy crops: perennial grass Miscanthus x Giganteus (Miscanthus) and short rotation coppice (SRC)-willow. The amount of SOC sequestered in the soil is a function of site-specific factors including soil texture, management practices, initial SOC levels and climate; for these reasons, both losses and gains in SOC were observed in previous Miscanthus and SRC-willow studies. The ECOSSE model was developed to simu...

  13. Allelopathic cover crop prior to seeding is more important than subsequent grazing/mowing in grassland establishment

    Science.gov (United States)

    Milchunas, Daniel G.; Vandever, Mark W.; Ball, Leonard O.; Hyberg, Skip

    2011-01-01

    The effects of grazing, mowing, and type of cover crop were evaluated in a previous winter wheat–fallow cropland seeded to grassland under the Conservation Reserve Program in eastern Colorado. Prior to seeding, the fallow strips were planted to forage sorghum or wheat in alternating strips (cover crops), with no grazing, moderate to heavy grazing, and mowing (grazing treatments) superimposed 4 yr after planting and studied for 3 yr. Plots previously in wheat had more annual and exotic species than sorghum plots. Concomitantly, there were much greater abundances of perennial native grass and all native species in sorghum than wheat cropped areas. The competitive advantage gained by seeded species in sorghum plots resulted in large increases in rhizomatous western wheatgrass. Sorghum is known to be allelopathic and is used in crop agriculture rotations to suppress weeds and increase crop yields, consistent with the responses of weed and desired native species in this study. Grazing treatment had relatively minor effects on basal and canopy cover composition of annual or exotic species versus perennial native grass or native species. Although grazing treatment never was a significant main effect, it occasionally modified cover crop or year effects. Opportunistic grazing reduced exotic cheatgrass by year 3 but also decreased the native palatable western wheatgrass. Mowing was a less effective weed control practice than grazing. Vegetative basal cover and aboveground primary production varied primarily with year. Common management practices for revegetation/restoration currently use herbicides and mowing as weed control practices and restrict grazing in all stages of development. Results suggest that allelopathic cover crop selection and opportunistic grazing can be effective alternative grass establishment and weed control practices. Susceptibility, resistance, and interactions of weed and seeded species to allelopathic cover species/cultivars may be a fruitful area

  14. Transpiration and crop yields

    NARCIS (Netherlands)

    Wit, de C.T.

    1958-01-01

    Theoretical and practical aspects of the transpiration of crops in the field are discussed and he concludes that the relationship between transpiration and total dry matter production is much less affected by growing conditions than has been supposed. In semi-arid and arid regions, this relationship

  15. Mycorrhiza and crop production

    Energy Technology Data Exchange (ETDEWEB)

    Hayman, D.S.

    1980-10-09

    This article describes recent research with vesicular-arbuscular mycorrhiza, a symbiotic fungus-root association. The suggestion that the symbiotic association may be harnessed to achieve more economical use of phosphate fertilizers is discussed and the results from various test crops are given.

  16. Orphan Crops Browser

    NARCIS (Netherlands)

    Kamei, Claire Lessa Alvim; Severing, E.I.; Dechesne, Annemarie; Furrer, Heleen; Dolstra, Oene; Trindade, L.M.

    2016-01-01

    Many important crops have received little attention by the scientific community, either because they are not considered economically important or due to their large and complex genomes. De novo transcriptome assembly, using next-generation sequencing data, is an attractive option for the study of

  17. Biotechnology Towards Energy Crops.

    Science.gov (United States)

    Margaritopoulou, Theoni; Roka, Loukia; Alexopoulou, Efi; Christou, Myrsini; Rigas, Stamatis; Haralampidis, Kosmas; Milioni, Dimitra

    2016-03-01

    New crops are gradually establishing along with cultivation systems to reduce reliance on depleting fossil fuel reserves and sustain better adaptation to climate change. These biological assets could be efficiently exploited as bioenergy feedstocks. Bioenergy crops are versatile renewable sources with the potential to alternatively contribute on a daily basis towards the coverage of modern society's energy demands. Biotechnology may facilitate the breeding of elite energy crop genotypes, better suited for bio-processing and subsequent use that will improve efficiency, further reduce costs, and enhance the environmental benefits of biofuels. Innovative molecular techniques may improve a broad range of important features including biomass yield, product quality and resistance to biotic factors like pests or microbial diseases or environmental cues such as drought, salinity, freezing injury or heat shock. The current review intends to assess the capacity of biotechnological applications to develop a beneficial bioenergy pipeline extending from feedstock development to sustainable biofuel production and provide examples of the current state of the art on future energy crops. PMID:26798073

  18. Crop yields in intercropping

    NARCIS (Netherlands)

    Yu, Y.

    2016-01-01

    Abstract

    Intercropping, the cultivation of two or more crop species simultaneously in the same field, has been widely practiced by smallholder farmers in developing countries and is gaining increasing interest in developed countries. Intercropping can increase the yield per

  19. Crop yield response to climate change varies with cropping intensity

    OpenAIRE

    Challinor, AJ; Parkes, B.; Ramirez-Villegas, J.

    2015-01-01

    Projections of the response of crop yield to climate change at different spatial scales are known to vary. However, understanding of the causes of systematic differences across scale is limited. Here, we hypothesize that heterogeneous cropping intensity is one source of scale dependency. Analysis of observed global data and regional crop modelling demonstrate that areas of high vs. low cropping intensity can have systematically different yields, in both observations and simulations. Analysis ...

  20. An index method to evaluate growers' pesticide use for identifying on-farm innovations and effective alternative pest management strategies: a case study of winegrape in Madera County, California

    Institute of Scientific and Technical Information of China (English)

    Wen-juan LI; Zhi-hao QIN; Ming-hua ZHANG; Joe BROWDE

    2011-01-01

    Winegrape is an important perennial crop in California, USA. Each year California winegrape farming consumes about 20 million kilograms of pesticides that have been a pollutant source to the fresh water systems of the state. The variation of pesticide use among winegrape growers has been significant. It has been observed that some growers have developed effective ways to reduce pesticide use, yet control pests efficiently to ensure harvest. Identification of the growers with low and high pesticide use is very helpful to extension programs that aim on reducing pesticide environmental risk. In this study, an index approach is proposed to quantitatively measure pesticide use intensity at grower level. An integrated pesticide use index is developed by taking pesticide quantity and toxicity into account. An additive formula and a multiplying formula were used to calculate the pesticide use index, i.e., PUl and PUIM It was found that both PUl and PUIM were capable of identifying the low and high pesticide users while PUI was slightly more conservative than PUIM. All pesticides used in California winegrape farming were taken into account for calculating the indices. Madera County, one of the largest winegrape producers in California, was taken as an example to test the proposed approach. In year 2000, among the total 208 winegrape growers, 28 with PUI≤10 and 34 with 10

  1. Bats in Agroecosytems around California's Central Coast

    Science.gov (United States)

    Wayne, A.

    2014-12-01

    Bats in agroecosystems around California's Central Coast: A full quarter of California's land area is farmland. Crops account for 32.5 billion of California's GDP. Insect control is a big problem for farmers, and California bats eat only insects, saving farmers an estimated 3 to $53 billion a year. As farmers maximize crop yield, they use more pesticides, herbicides, and fertilizers, which contaminate runoff streams that bats drink from. Also, pesticide use kills bats' sole food source: insects. My research objective was to find out how farm management practices and landscape complexity affect bat diversity and activity, and to see which one affects bat activity more. We monitored 18 sites, including conventional, organic, and low and high-complexity landscapes. We noted more bat activity at sites with high complexity landscapes and organic practices than at sites with either low-complexity landscapes or conventional farming practices. I captured and processed bats and recorded data. I also classified insects collected from light traps. I learned how to handle bats and measure forearm length and weight, as well as how to indentify their gender. I took hair clippings and fecal samples, which yield data about the bats' diet. Their diet, in turn, gives us data about which pests they eat and therefore help control. I also learned about bats' echolocation: they have a special muscle over their ears that closes when they echolocate so that they don't burst their own eardrum. Also, some insects have evolved a special call that will disrupt bats echolocation so bats can't track it.

  2. Crop responses to climatic variation

    OpenAIRE

    Porter, John R; Semenov, Mikhail A.

    2005-01-01

    The yield and quality of food crops is central to the well being of humans and is directly affected by climate and weather. Initial studies of climate change on crops focussed on effects of increased carbon dioxide (CO2) level and/or global mean temperature and/or rainfall and nutrition on crop production. However, crops can respond nonlinearly to changes in their growing conditions, exhibit threshold responses and are subject to combinations of stress factors that affect their growth, develo...

  3. Governing the GM crop revolution

    OpenAIRE

    Paarlberg, Robert L.

    2000-01-01

    Will developing countries adopt policies that promote the planting of genetically modified (GM) crops, or will they select policies that slow the spread of the GM crop revolution? The evidence so far is mixed. In some prominent countries such as China, policies are in place that encourage the independent development and planting of GM crops. Yet in a number of other equally prominent countries the planting of GM crops is not yet officially approved. The inclination of developing countries to ...

  4. Managing Risk with Crop Insurance

    OpenAIRE

    Edwards, William M.

    2003-01-01

    Every year Iowa farmers face the threat of damage to their crops from drought, hail, flood, insects, and other natural disasters. The U.S.D.A. Risk Management Agency (RMA) and private crop insurance venders have developed a set of insurance programs to help control crop production risks at a reasonable cost. Crop insurance coverage is not mandatory, but it does provide a financial safety net in case of severe production losses.

  5. SEASONALITY OF ANNUAL PLANT ESTABLISHMENT INFLUENCES THE INTERACTIONBETWEEN THE NON-NATIVE ANNUAL GRASS BROMUS MADRITENSIS SSP. RUBENS AND MOJAVE DESERT PERENNIALS

    Energy Technology Data Exchange (ETDEWEB)

    L A. DEFALCO; G. C. FERNANDEZ; R. S. NOWAK

    2004-01-01

    Competition between native and non-native species can change the composition and structure of plant communities, but in deserts the timing of non-native plant establishment can modulate their impacts to native species. In a field experiment, we varied densities of the non-native annual grass Bromus madritensis ssp. rubens around individuals of three native perennials--Larrea iridentata, Achnatherum hymenoides, and Pleuraphis rigida--in either winter or spring. Additional plots were prepared for the Same perennial species and seasons, but with a mixture of native annual species. Relative growth rates of perennial shoots (RGRs) declined with increasing Bromus biomass when Bromus that was established in winter had 2-3 mo of growth and high water use before perennial growth began. However, this high water use did not significantly reduce water potentials for the perennials, suggesting Bromus that established earlier depleted other soil resources, such as N, otherwise used by perennial plants. Spring-established Bromus had low biomass even at higher densities and did not effectively reduce RGRs, resulting in an overall lower impact to perennials than when Bromus was established in winter. Similarly, growth and reproduction of perennials with mixed annuals as neighbors did not differ from those with Bromus neighbors of equivalent biomass, but densities of these annuals did not support the high biomass necessary to reduce perennial growth. Thus, impacts of native Mojave Desert annuals to perennials are expected to be lower than those of Bromus because seed dormancy and narrow requirements for seedling survivorship produce densities and biomass lower than those achieved by Bromus. In comparing the effects of Bromus among perennial species, the impact of increased Bromus biomass on RGR was lower for Larrea than for the two perennial grasses, probably because Lurrea maintains low growth rates throughout the year, even after Bromus has completed its life cycle. This contrasts

  6. Salt resistant crop plants

    KAUST Repository

    Roy, Stuart J.

    2014-04-01

    Soil salinity is a major constraint to agriculture. To improve salinity tolerance of crops, various traits can be incorporated, including ion exclusion, osmotic tolerance and tissue tolerance. We review the roles of a range of genes involved in salt tolerance traits. Different tissues and cells are adapted for specific and often diverse function, so it is important to express the genes in specific cell-types and to pyramid a range of traits. Modern biotechnology (marker- assisted selection or genetic engineering) needs to be increasingly used to introduce the correct combination of genes into elite crop cultivars. Importantly, the effects of introduced genes need to be evaluated in the field to determine their effect on salinity tolerance and yield improvement.

  7. Investigating metrics proposed to prevent the harvest of leafy green crops contaminated by floodwater

    Science.gov (United States)

    The California Leafy Green Products Handler Marketing Agreement (LGMA) requires leafy green crops within 9 m of the edge of a flooded field not be harvested due to potential contamination. Further, previously flooded soils should not be replanted for 60 days. In this study, the suitability of the LG...

  8. Simulating coconut growth, development and yield with the InfoCrop-coconut model.

    Science.gov (United States)

    Kumar, S Naresh; Bai, K V Kasturi; Rajagopal, V; Aggarwal, P K

    2008-07-01

    Simulation modeling of perennial crops has immense potential for generating information for plantation managers. We report the development of the InfoCrop-coconut model and its application to coconut (Cocos nucifera L.) growing in diverse tropical and subtropical environments. The model is based on the generic crop model InfoCrop that simulates various annual crops in tropical and subtropical regions. The InfoCrop-coconut model was calibrated and validated with data compiled from published studies comprising many physiological, agronomical and nutritional experiments conducted between 1978 and 2005 in diverse geographic locations throughout India. The treatments included various water and nutrient regimes and varieties of coconut. Time to first flowering varied between 4 and 6 years, leaf production varied from 8 to 15 leaves year(-1) and nut yield ranged from 3000 to 27,000 nuts ha(-1) year(-1). The genetic coefficients used for calibration and validation were generated from field experiments conducted during 1995-2005. Model efficiency and validation performance were analyzed statistically. Simulated trends in phenological development, total dry mass and its partitioning, and nut yield agreed closely with observed values, although a 15% error was observed in a few cases. Considering that field measurements have an experimental error of 10-15% and wide variation existed within treatments, the model adequately simulated the effects of management practices and agro-climatic conditions over short periods. For a range of agro-climatic zones, simulated potential yields varied from 26 to 30 Mg ha(-1) year(-1) and potential annual dry mass production varied from 52 to 62 Mg ha(-1), depending on environment. We conclude that InfoCrop-coconut can be used to increase the efficiency of agronomic experiments designed to aid coconut crop management.

  9. Global Simulation of Bioenergy Crop Productivity: Analytical framework and Case Study for Switchgrass

    Energy Technology Data Exchange (ETDEWEB)

    Nair, S. Surendran [University of Tennessee, Knoxville (UTK); Nichols, Jeff A. {Cyber Sciences} [ORNL; Post, Wilfred M [ORNL; Wang, Dali [ORNL; Wullschleger, Stan D [ORNL; Kline, Keith L [ORNL; Wei, Yaxing [ORNL; Singh, Nagendra [ORNL; Kang, Shujiang [ORNL

    2014-01-01

    Contemporary global assessments of the deployment potential and sustainability aspects of biofuel crops lack quantitative details. This paper describes an analytical framework capable of meeting the challenges associated with global scale agro-ecosystem modeling. We designed a modeling platform for bioenergy crops, consisting of five major components: (i) standardized global natural resources and management data sets, (ii) global simulation unit and management scenarios, (iii) model calibration and validation, (iv) high-performance computing (HPC) modeling, and (v) simulation output processing and analysis. A case study with the HPC- Environmental Policy Integrated Climate model (HPC-EPIC) to simulate a perennial bioenergy crop, switchgrass (Panicum virgatum L.) and global biomass feedstock analysis on grassland demonstrates the application of this platform. The results illustrate biomass feedstock variability of switchgrass and provide insights on how the modeling platform can be expanded to better assess sustainable production criteria and other biomass crops. Feedstock potentials on global grasslands and within different countries are also shown. Future efforts involve developing databases of productivity, implementing global simulations for other bioenergy crops (e.g. miscanthus, energycane and agave), and assessing environmental impacts under various management regimes. We anticipated this platform will provide an exemplary tool and assessment data for international communities to conduct global analysis of biofuel biomass feedstocks and sustainability.

  10. Progress of the Research on the Conservation of Crop Germplasm Resources in China

    Institute of Scientific and Technical Information of China (English)

    LU Xin-xiong; CHEN Xiao-ling

    2003-01-01

    In the last 20 years, China has made considerable achievements in the conservation of crop germplasm resources. A network for crop germplasm conservation has been established by the end of 2002, which includes a national long-term seed genebank and its duplicated genebank, 8 national medium-term seed genebanks, 30 national field genebanks, 2 national in vitro genebanks, and 3 in situ conservation sites including 1 for wild soybean and 2 for wild rice. More than 334 000 crop germplasm accessions are currently stored in the national long-term genebank, covering 35 families, 192 genera and 712 species, which rank in the first place in the world. More than 43 000 accessions of vegetatively propagated crops and perennial crops covering more than 900 species are conserved in the national field genebanks. In addition, 2 300 accessions are stored in the national in vitro genebanks. This paper reviewed the latest advances of techniques for safety preservation of stored germplasm in seed genebank, ultra-dried seed storage and in vitro preservation in China and discussed current highlights in germplasm conservation.

  11. IMPORTANCE OF MAIZE CROPPING

    OpenAIRE

    Mohammed Dhary Yousif EL-JUBOURI

    2012-01-01

    The Corn, wheat and rice together are the main crops. It is a plant that responds well to chemical and organic fertilization and the irrigation. But compliance is sensitive to optimum sowing time and integrated control of weeds, pests and diseases (2). The maize is the most important plant product, from the point of view commercially and is used primarily as fodder. The maize is an important source of vegetable oil and has many applications in industry, the manufacture of diverse items: cosme...

  12. Soil testing for P and K has value in nutrient management for annual crops

    Directory of Open Access Journals (Sweden)

    Daniel Geisseler

    2016-08-01

    Full Text Available Adequate nutrients in forms available to plant roots are essential for sustainable crop production. Soil testing for phosphorus and potassium availability allows growers and crop advisers to determine whether a soil is likely to respond to fertilization. As yields have risen with improved management and production systems, crop nutrient demand and the removal of nutrients with harvested crops have increased. An in-depth discussion of soil tests for phosphorus and potassium and their use in California cropping systems is clearly needed. We review how these nutrients become available to plant roots, how samples are taken and test results interpreted, complementary ways to assess the adequacy of supplies and what research is needed to improve soil testing for phosphorus and potassium.

  13. Halophytes As Bioenergy Crops.

    Science.gov (United States)

    Sharma, Rita; Wungrampha, Silas; Singh, Vinay; Pareek, Ashwani; Sharma, Manoj K

    2016-01-01

    Shrinking arable land due to soil salinization and, depleting fresh water resources pose serious worldwide constraints to crop productivity. A vision of using plant feedstock for biofuel production can only be realized if we can identify alternate species that can be grown on saline soils and therefore, would not compete for the resources required for conventional agriculture. Halophytes have remarkable ability to grow under high salinity conditions. They can be irrigated with seawater without compromising their biomass and seed yields making them good alternate candidates as bioenergy crops. Both oil produced from the seeds and the lignocellulosic biomass of halophytes can be utilized for biofuel production. Several researchers across the globe have recognized this potential and assessed several halophytes for their tolerance to salt, seed oil contents and composition of their lignocellulosic biomass. Here, we review current advances and highlight the key species of halophytes analyzed for this purpose. We have critically assessed the challenges and opportunities associated with using halophytes as bioenergy crops.

  14. Halophytes As Bioenergy Crops

    Science.gov (United States)

    Sharma, Rita; Wungrampha, Silas; Singh, Vinay; Pareek, Ashwani; Sharma, Manoj K.

    2016-01-01

    Shrinking arable land due to soil salinization and, depleting fresh water resources pose serious worldwide constraints to crop productivity. A vision of using plant feedstock for biofuel production can only be realized if we can identify alternate species that can be grown on saline soils and therefore, would not compete for the resources required for conventional agriculture. Halophytes have remarkable ability to grow under high salinity conditions. They can be irrigated with seawater without compromising their biomass and seed yields making them good alternate candidates as bioenergy crops. Both oil produced from the seeds and the lignocellulosic biomass of halophytes can be utilized for biofuel production. Several researchers across the globe have recognized this potential and assessed several halophytes for their tolerance to salt, seed oil contents and composition of their lignocellulosic biomass. Here, we review current advances and highlight the key species of halophytes analyzed for this purpose. We have critically assessed the challenges and opportunities associated with using halophytes as bioenergy crops. PMID:27679645

  15. CROPS : high tech agricultural robots

    OpenAIRE

    Bontsema, J.; Hemming, J.; Pekkeriet, E.J.

    2014-01-01

    In the EU-funded CROPS (Clever Robots for Crops) project high tech robots are developed for site-specific spraying and selective harvesting of fruit and fruit vegetables. The harvesting robots are being designed to harvest high-value crops such as greenhouse vegetables, fruits in orchards and grapes for premium wines. The CROPS robots are also developed for canopy spraying in orchards and for precision target spraying in grape vines to reduce the use of pesticides. A CROPS robot will be able ...

  16. Home range, habitat selection, and movements of California black rails at tidal marshes at San Francisco Bay, California

    Science.gov (United States)

    Tsao, Danika C.; Takekawa, John Y.; Woo, Isa; Yee, Julie L.; Evens, Jules G.

    2009-01-01

    Little is known about the movements and habitat selection of California Black Rails (Laterallus jamaicensis coturniculus) in coastal California. We captured 130 Black Rails, of which we radio-marked 48, in tidal marshes in San Francisco Bay during 2005 and 2006. Our objective was to examine their home ranges, movements, and habitat selection to improve the species' conservation. The mean fixed-kernel home range was 0.59 ha, the mean core area was 0.14 ha. Home ranges and core areas did not differ by year or site. Males had significantly larger home ranges and core areas than did females. All sites combined, Black Rails used areas with > or = 94% total vegetative cover, with perennial pickleweed (Sarcocornia pacifica) the dominant plant. The rails' habitat selection varied by year and site but not by sex. A multivariate analysis of variance indicated that Black Rails selected areas with pickleweed taller and denser than average, greater cover and height of alkali bulrush (Bolboschoenus maritimus) and common saltgrass (Distichlis spicata), more stems between 20 and 30 cm above the ground, maximum vegetation height, and shorter distance to refugia. On average, Black Rails moved 27.6 +/- 1.8 (SE) m daily and 38.4 +/- 5.5 m during extreme high tides. Understanding the California Black Rail's movements, home range, and habitat use is critical for management to benefit the species.

  17. Genetic control of rhizomes and genomic localization of a major-effect growth habit QTL in perennial wildrye.

    Science.gov (United States)

    Yun, Lan; Larson, Steve R; Mott, Ivan W; Jensen, Kevin B; Staub, Jack E

    2014-06-01

    Rhizomes are prostrate subterranean stems that provide primitive mechanisms of vegetative dispersal, survival, and regrowth of perennial grasses and other monocots. The extent of rhizome proliferation varies greatly among grasses, being absent in cereals and other annuals, strictly confined in caespitose perennials, or highly invasive in some perennial weeds. However, genetic studies of rhizome proliferation are limited and genes controlling rhizomatous growth habit have not been elucidated. Quantitative trait loci (QTLs) controlling rhizome spreading were compared in reciprocal backcross populations derived from hybrids of rhizomatous creeping wildrye (Leymus triticoides) and caespitose basin wildrye (L. cinereus), which are perennial relatives of wheat. Two recessive QTLs were unique to the creeping wildrye backcross, one dominant QTL was unique to the basin wildrye backcross, and one additive QTL was detectable in reciprocal backcrosses with high log odds (LOD = 31.6) in the basin wildrye background. The dominant QTL located on linkage group (LG)-2a was aligned to a dominant rhizome orthogene (Rhz3) of perennial rice (Oryza longistamina) and perennial sorghum (Sorghum propinquum). Nonparametric 99 % confidence bounds of the 31.6-LOD QTL were localized to a distal 3.8-centiMorgan region of LG-6a, which corresponds to a 0.7-Mb region of Brachypodium Chromosome 3 containing 106 genes. An Aux/IAA auxin signal factor gene was located at the 31.6-LOD peak, which could explain the gravitropic and aphototropic behavior of rhizomes. Findings elucidate genetic mechanisms controlling rhizome development and architectural growth habit differences among plant species. Results have possible applications to improve perennial forage and turf grasses, extend the vegetative life cycle of annual cereals, such as wheat, or control the invasiveness of highly rhizomatous weeds such as quackgrass (Elymus repens). PMID:24509730

  18. BIOGAS PRODUCTION FROM CATCH CROPS

    DEFF Research Database (Denmark)

    Molinuevo-Salces, Beatriz; Larsen, Søren U.; Ahring, Birgitte Kiær;

    2014-01-01

    Catch crop cultivation combined with its use for biogas production would increase renewable energy production in the form of methane, without interfering with the production of food and fodder crops. The low biomass yield of catch crops is the main limiting factor for using these crops as co......-substrate in manure-based biogas plants and the profit obtained from the sale of biogas barely compensates for the harvest costs. A new agricultural strategy to harvest catch crops together with the residual straw of the main crop was investigated to increase the biomass and thereby the methane yield per hectare...... biomass. Leaving the straw on the field until harvest of the catch crop in the autumn could benefit biogas production due to the organic matter degradation of the straw taking place on the field during the autumn months. This new agricultural strategy may be a good alternative to achieve economically...

  19. Authentic Assessment in California.

    Science.gov (United States)

    Educational Leadership, 1989

    1989-01-01

    Describes the teacher-developed California Assessment Program (CAP) writing measure, designed to support California's reform curriculum and based on matrix sampling techniques. This program will be supplemented by literature and mathematics assessments. The greatest challenge is designing an assessment to match the state's new history and social…

  20. California's English Learner Students

    Science.gov (United States)

    Hill, Laura E.

    2012-01-01

    English Learner (EL) students in California's schools are numerous and diverse, and they lag behind their native-English-speaking peers. Closing the achievement gap for EL students has been a long-standing goal for California educators, and there are some signs of success. Now that EL funding and curriculum issues are receiving a fresh level of…

  1. Horticultural markets promote alien species invasions: an Estonian case study of herbaceous perennials

    Directory of Open Access Journals (Sweden)

    Merle Ööpik

    2013-06-01

    Full Text Available Gardening is a popular pastime, but commercial horticulture is responsible for the introduction of alien species and contributes to invasions in a variety of ways. Although an extensive international literature is available on plant invasions, it is still important at the national level to examine the influence of local factors. Accordingly, 17 nurseries in Estonia that cultivated and sold perennial alien species were selected, and a list of species and prices was compiled. The relationships between species status, and factors such as their abundance in the wild were examined statistically. A qualitative list of the nationally problematic species among herbaceous perennials was also completed. A total of 880 taxa were recorded, of which 10.3% were native and 89.7% alien. In all, 87.3% of the alien species were still confined to cultivated areas. The ecological and socio-economic characteristics of the taxa were described, and lists of the families of casual, naturalised and invasive aliens were provided. Both native and increasing wild alien species have a very similar profile on the market. Alien species that are less expensive, widely available and have more cultivars per species on the market are also more likely to escape. The invasive status and abundance of escaped aliens in an area increases with residence time. In general, socio-economic factors create new and reflect previous propagule pressures from commercial horticulture, which continuously increase the likelihood of alien species surviving and invading new areas. Our findings suggest that these national socio-economic market-related factors explain much of the invasiveness of various perennial ornamental species, and therefore regional and national authorities urgently need to regulate and control the ornamental plant trade to diminish the risk of new invasions.

  2. Effect of fertilization on N2O emissions from a marginal soil used for perennial grass bioenergy production

    Science.gov (United States)

    Stoof, Cathelijne; Karim, Imtiaz; Mason, Cedric; Tadipatri, Dhanya; Cary, Ian; Crawford, Ryan; Hansen, Julie; Crawford, Jamie; Mayton, Hilary; Steenhuis, Tammo; Richards, Brian

    2014-05-01

    Marginal lands constitute the primary land base available for development of bioenergy feedstocks in New York and the northeastern USA. Many of these soils are marginal because seasonal wetness prevents profitable row crop cultivation, but they are potentially suitable for perennial bioenergy feedstocks like switchgrass. Using these frequently wet soils for bioenergy production has multiple environmental and socio-economic benefits, yet little is known about how sustainable this practice is regarding greenhouse gas emissions - particularly in relation to the application of fertilizers. In a 2.2-ha field study near Ithaca, NY, USA, we are therefore monitoring greenhouse gas production from marginal silty clay loam soils cultivated with switchgrass. Here, we present results of our 2013 monitoring campaign, in which we assessed the effect of surface-applied granular ammonium sulfate-fertilizer (0, 56 and 112 kg N/ha) on N2O emissions along a natural catena from organic matter-rich wet lowland soil to drier midslope and upslope soils with higher rock fragment content. Sampling was done at 1 /2-week intervals around fertilization in June extending to 3-week intervals around harvest in September, giving a total of 15 sampling events. Emissions were sampled in a factorial design using four replicate static chambers per plot, and soil moisture, soil temperature and perched water table depth was assessed likewise. As expected, N2O emissions increased with N-fertilizer application. This effect of fertilization was much stronger than the effect of soil type or slope position. The greatest N2O fluxes were observed a few days after fertilization; we will explore and present the effects of rainfall, air temperature, soil moisture and soil temperature as potential drivers of smaller peaks occurring post-fertilization. Since the non-fertilized plots had negligible N2O emissions while still producing switchgrass at 6 Mg/ha, unfertilized switchgrass production is naturally most

  3. The Crop Journal Calls for Papers

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    We would like to invite you to submit your latest research accomplishments to The Crop Journal,an international,peer‐reviewed research publication covering all aspects of crop sciences including crop genetics,breeding,agronomy,crop physiology,germplasm resources,grain chemistry,grain storage and processing,crop management practices,crop biotechnology,and biomathematics on a bimonthly basis.

  4. Genomic Selection Using Genotyping-By-Sequencing Data with Different Coverage Depth in Perennial Ryegrass

    DEFF Research Database (Denmark)

    Cericola, Fabio; Janss, Luc; Byrne, Stephen;

    2015-01-01

    investigated how this reduction of the coverage depth affects the genomic relationship matrices used to estimated breeding value of F2 family pools in perennial ryegrass. A total of 995 families were genotyped via GBS providing more than 1.8M allele frequency estimates for each family with an average coverage...... depth of 12.6 per marker. Simulated datasets with a progressively reduced depth showed an increasing level of missing values together with an overestimated genetic variance caused by inflated diagonals in the genomic relationship matrix. In order to address these drawbacks we first showed how to correct...

  5. IQ Score of Children with Persistent or Perennial Allergic Rhinitis: A Comparison with Healthy Children

    OpenAIRE

    Ghaffari, Javad; Ali ABBASKHANIAN; Masumeh JALILI; Yazdani Charati, Jamshid

    2014-01-01

    How to Cite This Article: Ghaffari J, Abbaskhanian A, Jalili M, Yazdani Charati Y. IQ Score of Children With Persistent or Perennial Allergic Rhinitis: Comparison with Healthy Children. Iran J Child Neurol. 2014 Summer; 8(3): 44-48. AbstractObjectivePrevalence of allergies is different around the world. Allergic rhinitis is a common chronic disease in children.Intelligence quotient (IQ) is an indicator of efficacy and many factors including chronic diseases may affect it. This study compares ...

  6. Seasonal Variation of Provitamin D2 and Vitamin D2 in Perennial Ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Jäpelt, Rie Bak; Didion, Thomas; Smedsgaard, Jørn;

    2011-01-01

    Ergosterol (provitamin D(2)) is converted to vitamin D(2) in grass by exposure to UV light. Six varieties of perennial ryegrass (Lolium perenne L.) were harvested four times during the season, and the contents of vitamin D(2) and ergosterol were analyzed by a sensitive and selective liquid...... and vitamin D(2) change more than a factor of 10 during the season. These results demonstrate that grass potentially can be a significant source of vitamin D for grazing animals and animals fed on silage and hay....

  7. The Study of Perennial Grasses and Legumes Mixtures in the Environmental Conditions Part 1: The Evolution of Mixtures Productivity from Someşelor Plateau

    Directory of Open Access Journals (Sweden)

    Dorin-Benone Pleşa

    2012-05-01

    Full Text Available Lately it is a high interest in the establishing of temporary grasslands, these being considered a valuable source of fodder from the quantitative and qualitative point of view. Temporary grasslands can be established instead of degraded permanent grasslands or in arable lands. In the paper are presented the results of the research which took place in 2010 and 2011, regarding the fodder evolution of a double factor experience; A factor – mixtures (8 complex mixtures of perennial grasses and legumes and one alfalfa pure crop, considered as a witness,B factor – levels of fertilization (0N0P2O5, 60N70P2O5,120N70P2O5 kg·ha-1. In 2010 the highest productions (13.16 SU t·ha-1 were obtained at all the cycles from the 5th mixture composed from red clover and 4 species of grasses Trifolium pratense L., Dactylis glomerata L., Festulolium Asch. & Graebn., Phleum pratense L., Lolium perenne L.. In 2011, mixture number 3, recognized as being recommended for the forest steppe area and composed from Lotus corniculatus L.,Onobrychis viciifolia Scop., Dactylis glomerata L., Festuca pratensis Huds., Bromus inermis Leyss, presented the highest productions (4.82 t·ha-1 for the 60N70P2O5 and 120N70P2O5 kg·ha-1 levels of fertilization.

  8. Dispersion, distribution, and movement of Lygus spp. (Hemiptera: Miridae) in trap-cropped organic strawberries.

    Science.gov (United States)

    Swezey, Sean L; Nieto, Diego J; Hagler, James R; Pickett, Charles H; Bryer, Janet A; Machtley, Scott A

    2013-08-01

    Alfalfa (Medicago sativa L.) is a highly attractive plant host to Lygus spp. and is used as a trap crop in California organic strawberries to influence the dispersion and dispersal of these pests, particularly Lygus hesperus Knight. The abundance and distribution of Lygus spp. nymphs between two trap crops separated by 50 strawberry rows was analyzed in 2008 and 2010. Nymphs demonstrated a bimodal distribution in strawberries between trap crops, where nymphs were most abundant and aggregated in alfalfa, when compared with interior strawberry rows, where nymphs were less abundant. The majority of nymphs were concentrated in trap crops and nymphal densities in interior strawberry rows were well below economic thresholds. The movement of Lygus spp. from a marked alfalfa trap crop into adjacent strawberry rows or trap crops was also studied in 2008 and 2009 using a chicken egg albumin enzyme-linked immunosorbent assay mark-capture technique. The majority of marked-captured L. hesperus adults and Lygus spp. nymphs remained in alfalfa trap crops, rather than dispersing out into strawberry rows at 24 h, 48 h, and 2 wk, postprotein application. The attenuation of Lygus spp. movement in alfalfa associated with organic strawberries is a key component of successful trap cropping. A small percentage of marked adults and nymphs were captured in neighboring alfalfa trap crops, located 62 m from the point of protein application, highlighting the dispersal capacity of this key pest. PMID:23905741

  9. New Migrants vs. Old Migrants: Alternative Labor Market Structures in the California Citrus Industry

    OpenAIRE

    Mines, Richard; Anzaldua Montoya, Ricardo

    1982-01-01

    Based on fieldwork conducted during 1981 in Ventura County, California, this study helps to explain the relationship between the relative abundance of Mexican nationals willing to pick citrus crops and the institutional forms which U.S. unions, employers, and governments have created to deal with Mexicans in California agriculture. The work should be of particular relevance to those interested in the mechanisms through which Mexican nationals enter U.S. jobs and in the impact that immigrants...

  10. Native bees are a rich natural resource in urban California gardens

    OpenAIRE

    Gordon W. Frankie; Thorp, Robbin; Hernandez, Jennifer; Rizzardi, Mark; Ertter, Barbara; Pawelek, Jaime C.; Witt, Sara L.; Schindler, Mary; Coville, Rollin; Wojcik, Victoria

    2009-01-01

    Evidence is mounting that pollinators of crop and wildland plants are declining worldwide. Our research group at UC Berkeley and UC Davis conducted a 3-year survey of bee pollinators in seven cities from Northern California to Southern California. Results indicate that many types of urban residential gardens provide floral and nesting resources for the reproduction and survival of bees, especially a diversity of native bees. Habitat gardening for bees, using targeted ornamental plants, can pr...

  11. GEOGLAM Crop Monitor Assessment Tool: Developing Monthly Crop Condition Assessments

    Science.gov (United States)

    McGaughey, K.; Becker Reshef, I.; Barker, B.; Humber, M. L.; Nordling, J.; Justice, C. O.; Deshayes, M.

    2014-12-01

    The Group on Earth Observations (GEO) developed the Global Agricultural Monitoring initiative (GEOGLAM) to improve existing agricultural information through a network of international partnerships, data sharing, and operational research. This presentation will discuss the Crop Monitor component of GEOGLAM, which provides the Agricultural Market Information System (AMIS) with an international, multi-source, and transparent consensus assessment of crop growing conditions, status, and agro-climatic conditions likely to impact global production. This activity covers the four primary crop types (wheat, maize, rice, and soybean) within the main agricultural producing regions of the AMIS countries. These assessments have been produced operationally since September 2013 and are published in the AMIS Market Monitor Bulletin. The Crop Monitor reports provide cartographic and textual summaries of crop conditions as of the 28th of each month, according to crop type. This presentation will focus on the building of international networks, data collection, and data dissemination.

  12. Coping with naturally-high levels of soil salinity and boron in the westside of central California

    Directory of Open Access Journals (Sweden)

    Gary S. Bañuelos

    2015-02-01

    Full Text Available California has one of the most productive agricultural regions of the world, producing more than 400 commodities with a value of more than $37 billion. In the westside of central California, over 200,000 ha exhibit naturally high levels of salinity and boron (B in the soils, especially those derived from Cretaceous soils. Both excessive salt and B negatively impact agronomic production in this part of California, which has severe economic consequences for the farming communities. Developing new salt and B management methods and identifying alternative tolerant crops are essential agronomic strategies for this region of California.

  13. Global transcriptome changes in perennial ryegrass during early infection by pink snow mould.

    Science.gov (United States)

    Kovi, Mallikarjuna Rao; Abdelhalim, Mohamed; Kunapareddy, Anil; Ergon, Åshild; Tronsmo, Anne Marte; Brurberg, May Bente; Hofgaard, Ingerd Skow; Asp, Torben; Rognli, Odd Arne

    2016-01-01

    Lack of resistance to pink snow mould (Microdochium nivale) is a major constraint for adaptation of perennial ryegrass (Lolium perenne L.) to continental regions with long-lasting snow cover at higher latitudes. Almost all investigations of genetic variation in resistance have been performed using cold acclimated plants. However, there may be variation in resistance mechanisms that are functioning independently of cold acclimation. In this study our aim was to identify candidate genes involved in such resistance mechanisms. We first characterized variation in resistance to M. nivale among non-acclimated genotypes from the Norwegian cultivar 'Fagerlin' based on relative regrowth and fungal quantification by real-time qPCR. One resistant and one susceptible genotype were selected for transcriptome analysis using paired-end sequencing by Illumina Hiseq 2000. Transcriptome profiles, GO enrichment and KEGG pathway analysis indicate that defense response related genes are differentially expressed between the resistant and the susceptible genotype. A significant up-regulation of defense related genes, as well as genes involved in cell wall cellulose metabolic processes and aryl-alcohol dehydrogenase (NADP+) activity, was observed in the resistant genotype. The candidate genes identified in this study might be potential molecular marker resources for breeding perennial ryegrass cultivars with improved resistance to pink snow mould. PMID:27346054

  14. Seasonal changes in oleosomic lipids and fatty acids of perennial root nodules of beach pea.

    Science.gov (United States)

    Chinnasamy, Gurusamy; Davis, Philip James; Bal, Arya Kumar

    2003-04-01

    Seasonal changes in the fatty acid composition of phospholipids (PL), monoglycerides (MG), diglycerides (DG), free fatty acids (FA) and triglycerides (TG) separated from oleosomes (lipid bodies) of perennial root nodules of beach pea (Lathyrus maritimus) were analysed. Thin layer chromatography (TLC) revealed that PL and MG are the major lipids in nodule oleosomes. The fatty acid profile and overall double bond index (DBI) varied among lipid classes depending upon the season. High DBI in PL and MG found during late winter and early spring indicated that they may play a major role in winter survival and regeneration of perennial nodules. The DBI of DG was high at the end of the fall season and the DBI of FA and TG was high in summer months. The dominant fatty acids are C16:0 followed by C18:0 and C18:1. The levels of many unsaturated fatty acids such as C18:1, C18:2 and C18:3 increased while saturated fatty acid C18:0 decreased during winter. These unsaturated fatty acids possibly play an important role in the protection of nodule cells from cold stress. Nodules seem to retain some fatty acids and selectively utilize specific fatty acids to survive the winter and regenerate in spring. PMID:12756915

  15. Application of perennial legume green manures to improve growth and yield of organic lowland rice

    Directory of Open Access Journals (Sweden)

    M Winarni

    2016-10-01

    Full Text Available A pot experiment in green house was done to study the effect of the dosage and speciesof perennial legume green manures to the physiological traits, growth and yield of organic lowland rice (Oryza sativaL., and to obtain the optimal dosage as well.  The research was arranged in a factorial randomized block design consistedof two factors with three replications.The first factor was the species of perennial legume thatconsisted of threespecies: Turi (Sesbaniagrandiflora, Glirisidia (Gliricidiasepium, and Lamtoro (Leucaenaleucocephala and cow manure as control treatment. The second factor was the dosage of green manure thatconsisted of four levels: 5, 10, 20 and 40 t/ha.  The results showed that application ofperennial legumesinto the soil significantly improved the growth and yield of rice.  The application of  20 t Glirisidia leaves/haproduced the highest grain yield, followed by 20 t Lamtoro leaves/ha and 20 t Turi leaves/ha.  The optimal dosages of S. grandiflora, G. sepium and L. leucochepala leaves that could yield 58.03 g/hill (equivalent to14.51 t/ha, 53.67 g/hill (equivalent to 13.42 t/ha, and 49.67 g/hill (equivalent to 12.42 t/ha were 28.05, 25.46 and 26.41 t/ha, respectively.

  16. Root Characteristics of Perennial Warm-Season Grasslands Managed for Grazing and Biomass Production

    Directory of Open Access Journals (Sweden)

    Rattan Lal

    2013-07-01

    Full Text Available Minirhizotrons were used to study root growth characteristics in recently established fields dominated by perennial C4-grasses that were managed either for cattle grazing or biomass production for bioenergy in Virginia, USA. Measurements over a 13-month period showed that grazing resulted in smaller total root volumes and root diameters. Under biomass management, root volume was 40% higher (49 vs. 35 mm3 and diameters were 20% larger (0.29 vs. 0.24 mm compared to grazing. While total root length did not differ between grazed and biomass treatments, root distribution was shallower under grazed areas, with 50% of total root length in the top 7 cm of soil, compared to 41% in ungrazed exclosures. These changes (i.e., longer roots and greater root volume in the top 10 cm of soil under grazing but the reverse at 17–28 cm soil depths were likely caused by a shift in plant species composition as grazing reduced C4 grass biomass and allowed invasion of annual unsown species. The data suggest that management of perennial C4 grasslands for either grazing or biomass production can affect root growth in different ways and this, in turn, may have implications for the subsequent carbon sequestration potential of these grasslands.

  17. Global transcriptome changes in perennial ryegrass during early infection by pink snow mould

    Science.gov (United States)

    Kovi, Mallikarjuna Rao; Abdelhalim, Mohamed; Kunapareddy, Anil; Ergon, Åshild; Tronsmo, Anne Marte; Brurberg, May Bente; Hofgaard, Ingerd Skow; Asp, Torben; Rognli, Odd Arne

    2016-01-01

    Lack of resistance to pink snow mould (Microdochium nivale) is a major constraint for adaptation of perennial ryegrass (Lolium perenne L.) to continental regions with long-lasting snow cover at higher latitudes. Almost all investigations of genetic variation in resistance have been performed using cold acclimated plants. However, there may be variation in resistance mechanisms that are functioning independently of cold acclimation. In this study our aim was to identify candidate genes involved in such resistance mechanisms. We first characterized variation in resistance to M. nivale among non-acclimated genotypes from the Norwegian cultivar ‘Fagerlin’ based on relative regrowth and fungal quantification by real-time qPCR. One resistant and one susceptible genotype were selected for transcriptome analysis using paired-end sequencing by Illumina Hiseq 2000. Transcriptome profiles, GO enrichment and KEGG pathway analysis indicate that defense response related genes are differentially expressed between the resistant and the susceptible genotype. A significant up-regulation of defense related genes, as well as genes involved in cell wall cellulose metabolic processes and aryl-alcohol dehydrogenase (NADP+) activity, was observed in the resistant genotype. The candidate genes identified in this study might be potential molecular marker resources for breeding perennial ryegrass cultivars with improved resistance to pink snow mould. PMID:27346054

  18. PERENNIAL HELIANTHUS TAXA IN TÂRGU-MURES CITY AND ITS SURROUNDINGS

    Directory of Open Access Journals (Sweden)

    FILEP RITA

    2010-12-01

    Full Text Available Although in the neighbouring countries several perennial Helianthus taxa have been recorded in the last decade, in Romania only three have been identified so far. The literature and herbaria data of Târgu-Mures date back to the end of the XIXth century, and only refer to H. × multiflorus and H. tuberosus. The aim of this study was to identify the perennial Helianthus taxa in this region and to prepare their current distribution map. The survey was conducted in Târgu Mures city and the neighbouring villages: Livezeni, Sântana de Mures, Sâncraiu de Mures, Sângeorgiu de Mures, and Corunca. Four taxa were identified: H. pauciflorus Nutt., H. × laetiflorus Pers., H. tuberosus L. s.str., and Helianthus tuberosus L. s.l. The first two taxa are cultivated as ornamental plants, H. tuberosus s. str. is cultivated in a few farms, whereas H. tuberosus s. l. is an invasive species that spreads along the rivers.

  19. Syngas Production from Pyrolysis of Nine Composts Obtained from Nonhybrid and Hybrid Perennial Grasses

    Directory of Open Access Journals (Sweden)

    Adéla Hlavsová

    2014-01-01

    Full Text Available A pyrolysis of compost for the production of syngas with an explicit H2/CO = 2 or H2/CO = 3 was investigated in this study. The composts were obtained from nonhybrid (perennial grasses (NHG and hybrid (perennial grasses (HG. Discrepancies in H2 evolution profiles were found between NHG and HG composts. In addition, positive correlations for NHG composts were obtained between (i H2 yield and lignin content, (ii H2 yield and potassium content, and (iii CO yield and cellulose content. All composts resulted in H2/CO = 2 and five of the nine composts resulted in H2/CO = 3. Exceptionally large higher heating values (HHVs of pyrolysis gas, very close to HHVs of feedstock, were obtained for composts made from mountain brome (MB, 16.23 MJ/kg, hybrid Becva (FB, 16.45 MJ/kg, and tall fescue (TF, 17.43 MJ/kg. The MB and FB composts resulted in the highest syngas formation with H2/CO = 2, whereas TF compost resulted in the highest syngas formation with H2/CO = 3.

  20. Role of antioxidants on the clinical outcome of patients with perennial allergic rhinitis

    Science.gov (United States)

    Gupta, Manish; Chauhan, Komal

    2016-01-01

    Background: Antioxidants have a preventive or therapeutic role in oxygen free radical–mediated cell and tissue damage. The study aimed to investigate the therapeutic effects of antioxidants and intranasal steroid fluticasone furoate (FF) on the clinical outcome of patients with perennial allergic rhinitis. Methods: Subjects with perennial allergic rhinitis (n = 61) were randomly divided into two groups, group A (n = 30) received FF and group B (n = 31) received FF with antioxidants for 6 weeks. Nasal and ocular symptoms were evaluated weekly by using a four-point categoric scale. The efficacy of the study drug was assessed based on the mean change from baseline of the total daytime nasal symptom scores, total nighttime nasal symptom scores, and the composite symptom scores. Results: The combined therapy (FF with antioxidants) resulted in marked improvements (p ≤ 0.05) in the mean total daytime nasal symptom scores, total nighttime nasal symptom scores, and composite symptom scores of subjects compared with ones treated with intranasal steroid (FF) alone, which highlighted the therapeutic effect of antioxidants in allergic rhinitis. Conclusion: Significant improvement in clinical outcome was observed in subjects who received antioxidants along with FF. However, because this was an open-label study, the results must be interpreted with caution, and further double-blind, placebo-controlled, dose-ranging trials supplemented with different antioxidants together with intranasal steroids are suggested.

  1. IMPACT OF GROWTH INHIBITOR BERCEMA ON SHOOTS REGROWTH OF PERENNIAL RYEGRASS AND COCKSFOOT

    Directory of Open Access Journals (Sweden)

    Beata Wiśniewska-Kadżajan

    2014-04-01

    Full Text Available In a pot experiment conducted in a greenhouse, the effect of CCC Bercema growth inhibitor to reduce vegetative shoot growth of perennial ryegrass and cocksfoot was studded. The experiment was set up in triplicate. Growth regulator was applied once, in a form of an aqueous solution. The following experimental objects were specified: control object, Bercema with a concentration of 10%, 20% and 30%. Ten measurements were performed every 3 days. The study was conducted under conditions of 12-hour artificial light daily. The results were statistically analyzed using two-factorial variance analysis . It was found that the greatest shoot growth reduction of ryegrass due to the highest inhibitor concentration (B- 30%, but for cocksfoot under the influence of the minimal concentration (B- 10%, compared to the control object. It has been noted that cocksfoot is more sensitive to the applied growth regulator, resulted in significantly greater inhibition of shoot regrowth than for ryegrass. In the experiment with the perennial ryegrass significant differences in the growth of shoots were found under the influence of inhibitor application at a concentration of 30%, compared to the control object. In the case of cocksfoot, all the concentration increases of Bercema inhibitor significantly differentiated the shoots regrowth.

  2. Size-Dependent Flowering in relation to Grazing in a Short-Lived Monocarpic Perennial

    Directory of Open Access Journals (Sweden)

    Diana E. Marco

    2014-01-01

    Full Text Available In short-lived monocarpic perennials flowering probability depends on size and relative growth. Reproducing at a smaller size results in a higher prereproductive survival and shorter generation time but also may lead to lower fecundity. Conversely, reproducing at a larger size allows greater fecundity but leads to higher mortality during the prolonged vegetative period. Herbivory may influence the above described relationships via alterations in size at reproduction and survival. Here we use field data to explore in detail the reproduction of the short-lived monocarpic perennial C. vulgare under seasonal grazing. Vegetative plants were marked in paddocks with and without winter grazing, and their size, growth, and flowering status were recorded during a growing season in a field grazing experiment. Grazing increased both survival of vegetative plants and flowering probability, but it did not affect flowering size. The increase in flowering probability is a result of differential plant growth and size and may be related to greater resource availability, including light (necessary for flowering induction in C. vulgare in grazed paddocks.

  3. Global transcriptome changes in perennial ryegrass during early infection by pink snow mould.

    Science.gov (United States)

    Kovi, Mallikarjuna Rao; Abdelhalim, Mohamed; Kunapareddy, Anil; Ergon, Åshild; Tronsmo, Anne Marte; Brurberg, May Bente; Hofgaard, Ingerd Skow; Asp, Torben; Rognli, Odd Arne

    2016-01-01

    Lack of resistance to pink snow mould (Microdochium nivale) is a major constraint for adaptation of perennial ryegrass (Lolium perenne L.) to continental regions with long-lasting snow cover at higher latitudes. Almost all investigations of genetic variation in resistance have been performed using cold acclimated plants. However, there may be variation in resistance mechanisms that are functioning independently of cold acclimation. In this study our aim was to identify candidate genes involved in such resistance mechanisms. We first characterized variation in resistance to M. nivale among non-acclimated genotypes from the Norwegian cultivar 'Fagerlin' based on relative regrowth and fungal quantification by real-time qPCR. One resistant and one susceptible genotype were selected for transcriptome analysis using paired-end sequencing by Illumina Hiseq 2000. Transcriptome profiles, GO enrichment and KEGG pathway analysis indicate that defense response related genes are differentially expressed between the resistant and the susceptible genotype. A significant up-regulation of defense related genes, as well as genes involved in cell wall cellulose metabolic processes and aryl-alcohol dehydrogenase (NADP+) activity, was observed in the resistant genotype. The candidate genes identified in this study might be potential molecular marker resources for breeding perennial ryegrass cultivars with improved resistance to pink snow mould.

  4. Poplar-Root Knot Nematode Interaction: A Model for Perennial Woody Species.

    Science.gov (United States)

    Baldacci-Cresp, Fabien; Sacré, Pierre-Yves; Twyffels, Laure; Mol, Adeline; Vermeersch, Marjorie; Ziemons, Eric; Hubert, Philippe; Pérez-Morga, David; El Jaziri, Mondher; de Almeida Engler, Janice; Baucher, Marie

    2016-07-01

    Plant root-knot nematode (RKN) interaction studies are performed on several host plant models. Though RKN interact with trees, no perennial woody model has been explored so far. Here, we show that poplar (Populus tremula × P. alba) grown in vitro is susceptible to Meloidogyne incognita, allowing this nematode to penetrate, to induce feeding sites, and to successfully complete its life cycle. Quantitative reverse transcription-polymerase chain reaction analysis was performed to study changes in poplar gene expression in galls compared with noninfected roots. Three genes (expansin A, histone 3.1, and asparagine synthase), selected as gall development marker genes, followed, during poplar-nematode interaction, a similar expression pattern to what was described for other plant hosts. Downregulation of four genes implicated in the monolignol biosynthesis pathway was evidenced in galls, suggesting a shift in the phenolic profile within galls developed on poplar roots. Raman microspectroscopy demonstrated that cell walls of giant cells were not lignified but mainly composed of pectin and cellulose. The data presented here suggest that RKN exercise conserved strategies to reproduce and to invade perennial plant species and that poplar is a suitable model host to study specific traits of tree-nematode interactions. PMID:27135257

  5. IQ Score of Children with Persistent or Perennial Allergic Rhinitis: A Comparison with Healthy Children

    Science.gov (United States)

    GHAFFARI, Javad; ABBASKHANIAN, Ali; JALILI, Masumeh; YAZDANI CHARATI, Jamshid

    2014-01-01

    Objective Prevalence of allergies is different around the world. Allergic rhinitis is a common chronic disease in children. Intelligence quotient (IQ) is an indicator of efficacy and many factors including chronic diseases may affect it. This study compares the IQs of children diagnosed with persistent or perennial allergic rhinitis with healthy children. Material & Methods This was a comparative study that was conducted from June 2011–May 2013 in an academic referral clinic. In this study, 90 patients aged 6- to 14-yearsold who were diagnosed with persistent or perennial allergic rhinitis and were compared to 90 age and gender match healthy patients from their respective families. The Wechsler Intelligence Scale for Children was used to divide and calculate overall IQ, verbal IQ, and practical IQ. The t-test and chi square were used to analyze quantitative variables and qualitative variables, respectively. Results In this study, out of total 180 children, 90 (50%) in the case group and 90 children (50%), the control group participated for IQ comparison. One hundred (57%) were male and 80 (43%) were female. The overall IQ for allergic rhinitis patients and healthy patients was 109.2 and 107.5, respectively. This difference was not considered significant. Furthermore, there was no significant difference between the IQ scores of males and females. Conclusion Although allergic rhinitis is a chronic disease and effects quality of life, there were no identifiable negative effects on IQ. PMID:25143773

  6. PypeTree: A Tool for Reconstructing Tree Perennial Tissues from Point Clouds

    Directory of Open Access Journals (Sweden)

    Sylvain Delagrange

    2014-03-01

    Full Text Available The reconstruction of trees from point clouds that were acquired with terrestrial LiDAR scanning (TLS may become a significant breakthrough in the study and modelling of tree development. Here, we develop an efficient method and a tool based on extensive modifications to the skeletal extraction method that was first introduced by Verroust and Lazarus in 2000. PypeTree, a user-friendly and open-source visual modelling environment, incorporates a number of improvements into the original skeletal extraction technique, making it better adapted to tackle the challenge of tree perennial tissue reconstruction. Within PypeTree, we also introduce the idea of using semi-supervised adjustment tools to address methodological challenges that are associated with imperfect point cloud datasets and which further improve reconstruction accuracy. The performance of these automatic and semi-supervised approaches was tested with the help of synthetic models and subsequently validated on real trees. Accuracy of automatic reconstruction greatly varied in terms of axis detection because small (length < 3.5 cm branches were difficult to detect. However, as small branches account for little in terms of total skeleton length, mean reconstruction error for cumulated skeleton length only reached 5.1% and 1.8% with automatic or semi-supervised reconstruction, respectively. In some cases, using the supervised tools, a perfect reconstruction of the perennial tissue could be achieved.

  7. The influence of drought and heat stress on long-term carbon fluxes of bioenergy crops grown in the Midwestern USA.

    Science.gov (United States)

    Joo, Eva; Hussain, Mir Zaman; Zeri, Marcelo; Masters, Michael D; Miller, Jesse N; Gomez-Casanovas, Nuria; DeLucia, Evan H; Bernacchi, Carl J

    2016-09-01

    Perennial grasses are promising feedstocks for bioenergy production in the Midwestern USA. Few experiments have addressed how drought influences their carbon fluxes and storage. This study provides a direct comparison of ecosystem-scale measurements of carbon fluxes associated with miscanthus (Miscanthus × giganteus), switchgrass (Panicum virgatum), restored native prairie and maize (Zea mays)/soybean (Glycine max) ecosystems. The main objective of this study was to assess the influence of a naturally occurring drought during 2012 on key components of the carbon cycle and plant development relative to non-extreme years. The perennials reached full maturity 3-5 years after establishment. Miscanthus had the highest gross primary production (GPP) and lowest net ecosystem exchange (NEE) in 2012 followed by similar values for switchgrass and prairie, and the row crops had the lowest GPP and highest NEE. A post-drought effect was observed for miscanthus. Over the duration of the experiment, perennial ecosystems were carbon sinks, as indicated by negative net ecosystem carbon balance (NECB), while maize/soybean was a net carbon source. Our observations suggest that perennial ecosystems, and in particular miscanthus, can provide a high yield and a large potential for CO2 fixation even during drought, although drought may negatively influence carbon uptake in the following year, questioning the long-term consequence of its maintained productivity.

  8. The influence of drought and heat stress on long-term carbon fluxes of bioenergy crops grown in the Midwestern USA.

    Science.gov (United States)

    Joo, Eva; Hussain, Mir Zaman; Zeri, Marcelo; Masters, Michael D; Miller, Jesse N; Gomez-Casanovas, Nuria; DeLucia, Evan H; Bernacchi, Carl J

    2016-09-01

    Perennial grasses are promising feedstocks for bioenergy production in the Midwestern USA. Few experiments have addressed how drought influences their carbon fluxes and storage. This study provides a direct comparison of ecosystem-scale measurements of carbon fluxes associated with miscanthus (Miscanthus × giganteus), switchgrass (Panicum virgatum), restored native prairie and maize (Zea mays)/soybean (Glycine max) ecosystems. The main objective of this study was to assess the influence of a naturally occurring drought during 2012 on key components of the carbon cycle and plant development relative to non-extreme years. The perennials reached full maturity 3-5 years after establishment. Miscanthus had the highest gross primary production (GPP) and lowest net ecosystem exchange (NEE) in 2012 followed by similar values for switchgrass and prairie, and the row crops had the lowest GPP and highest NEE. A post-drought effect was observed for miscanthus. Over the duration of the experiment, perennial ecosystems were carbon sinks, as indicated by negative net ecosystem carbon balance (NECB), while maize/soybean was a net carbon source. Our observations suggest that perennial ecosystems, and in particular miscanthus, can provide a high yield and a large potential for CO2 fixation even during drought, although drought may negatively influence carbon uptake in the following year, questioning the long-term consequence of its maintained productivity. PMID:27043723

  9. Cell wall proteomics of crops

    OpenAIRE

    Komatsu, Setsuko; Yanagawa, Yuki

    2013-01-01

    Cell wall proteins play key roles in cell structure and metabolism, cell enlargement, signal transduction, responses to environmental stress, and many other physiological events. Agricultural crops are often used for investigating stress tolerance because cultivars with differing degrees of tolerance are available. Abiotic and biotic stress factors markedly influence the geographical distribution and yields of many crop species. Crop cell wall proteomics is of particular importance for improv...

  10. Crop responses to climatic variation

    DEFF Research Database (Denmark)

    Porter, John R.; Semenov, Mikhail A.

    2005-01-01

    production. However, crops can respond nonlinearly to changes in their growing conditions, exhibit threshold responses and are subject to combinations of stress factors that affect their growth, development and yield. Thus, climate variability and changes in the frequency of extreme events are important...... of adaptation possibilities for crops in response to drought and argues that characters that enable better exploration of the soil and slower leaf canopy expansion could lead to crop higher transpiration efficiency....

  11. Investigating Impacts of Alternative Crop Market Scenarios on Land Use Change with an Agent-Based Model

    Directory of Open Access Journals (Sweden)

    Deng Ding

    2015-11-01

    Full Text Available We developed an agent-based model (ABM to simulate farmers’ decisions on crop type and fertilizer application in response to commodity and biofuel crop prices. Farm profit maximization constrained by farmers’ profit expectations for land committed to biofuel crop production was used as the decision rule. Empirical parameters characterizing farmers’ profit expectations were derived from an agricultural landowners and operators survey and integrated in the ABM. The integration of crop production cost models and the survey information in the ABM is critical to producing simulations that can provide realistic insights into agricultural land use planning and policy making. Model simulations were run with historical market prices and alternative market scenarios for corn price, soybean to corn price ratio, switchgrass price, and switchgrass to corn stover ratio. The results of the comparison between simulated cropland percentage and crop rotations with satellite-based land cover data suggest that farmers may be underestimating the effects that continuous corn production has on yields. The simulation results for alternative market scenarios based on a survey of agricultural land owners and operators in the Clear Creek Watershed in eastern Iowa show that farmers see cellulosic biofuel feedstock production in the form of perennial grasses or corn stover as a more risky enterprise than their current crop production systems, likely because of market and production risks and lock in effects. As a result farmers do not follow a simple farm-profit maximization rule.

  12. California Ocean Uses Atlas

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is a result of the California Ocean Uses Atlas Project: a collaboration between NOAA's National Marine Protected Areas Center and Marine Conservation...

  13. California Watershed Hydrologic Units

    Data.gov (United States)

    California Department of Resources — This dataset is intended to be used as a tool for water-resource management and planning activities, particularly for site-specific and localized studies requiring...

  14. Earthquakes in Southern California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — There have been many earthquake occurrences in Southern California. This set of slides shows earthquake damage from the following events: Imperial Valley, 1979,...

  15. Coastal California Digital Imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This digital ortho-imagery dataset is a survey of coastal California. The project area consists of approximately 3774 square miles. The project design of the...

  16. California Harpoon Fishery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vessel logbook and landings data from harpoon vessels that fish within 200 miles of the California coast, from 1974 to present. The harpoon...

  17. The Oxbow School, California.

    Science.gov (United States)

    Pearson, Clifford A.

    2003-01-01

    Describes the design of the Oxbow School, an art- and design-oriented high school in Napa, California, including the educational context and design goals. Includes information on the architects, as well as floor plans and photographs. (EV)

  18. California Data Exchange Center

    Science.gov (United States)

    ... to make July &28;Water Smart Month.&29; &28;Conserving ... Remote sensors today indicate that statewide, snowpack water content is 54 percent of ... California ranked first, along with Texas, on ...

  19. 605 Salad crops: Root, bulb, and tuber Crops

    Science.gov (United States)

    Root and tuber crops (potato, cassava, sweet potato, and yams) comprise 4 of the 10 major food staples of the world and serve as a major source of energy for the poor of developing nations. Minimal strain placed on agro ecosystems by root and tuber crops highlight their welcomed contribution to the ...

  20. Genetically Modified Crops and Labor Savings in US Crop Production

    OpenAIRE

    Gardner, Justin G.; Nelson, Carl H.

    2007-01-01

    In spite of widespread adoption there is mixed evidence as to whether or not adopting Genetically Modified (GM) crops increase farm welfare. One possible reason for widespread adoption is labor savings. Using a treatment effect model we estimate the labor savings associated with adopting a GM crop.

  1. Crop Ontology: Vocabulary For Crop-related Concepts

    NARCIS (Netherlands)

    Matteis, L.; Chibon, P.Y.; Espinosa, H.; Skofic, M.; Finkers, H.J.; Bruskiewich, R.; Hyman, J.M.; Arnoud, E.

    2013-01-01

    Abstract. A recurrent issue for data integration is the lack of a common and structured vocabulary used by different parties to describe their data sets. The Crop Ontology (www.cropontology.org) project aims to provide a central place where the crop community can gather to generate such standardized

  2. Investigating Root Zone Soil Moisture Using Electrical Resistivity and Crop Modeling

    Science.gov (United States)

    Diker, K.; Van Dam, R. L.; Hyndman, D. W.; Kendall, A. D.; Bhardwaj, A. K.; Hamilton, S. K.; Basso, B.

    2011-12-01

    An accurate understanding of soil moisture variability is critical for agroecological modeling and for understanding the implications of climate change for agriculture. In recent years, electrical resistivity (ER) methods have successfully been used to characterize soil moisture in a range of environments, but there remains a need to better link these data to climate variability, soil textural properties, and vegetation and root dynamics. We present results for a novel ER measurement system at the Great Lakes Bioenergy Research Center (GLBRC) in southwest Michigan. Permanent multi-electrode arrays were installed beneath a range of annual and perennial biofuel crop types including corn, soybean, various grasses, and poplars. The ER arrays provide both high spatial resolution 2D and high temporal resolution 1D apparent resistivity data (4 week and 2 hour intervals, respectively). These data, along with a forward simulation of electrical resistivity in the soil column, are used to calibrate and refine root growth dynamics modules within the crop growth and soil hydrologic model SALUS (System Approach to Land Use Sustainability). Simulations are compared to 1D TDR-inferred soil moisture data. Variability in root zone dynamics among different biofuel cropping systems is explored. Total water use and efficiency, along with profile root water extraction, vary considerably among the crops.

  3. Root biomass and soil carbon response to growing perennial grasses for bioenergy

    Science.gov (United States)

    Dedicated bioenergy crops such as switchgrass (Panicum virgatum L.), miscanthus [Miscanthus x giganteus (Mxg)], indiangrass [Sorghastrum nutans (L.) Nash], and big bluestem (Andropogon gerardii Vitman) can provide cellulosic feedstock for biofuel production while maintaining or improving soil and en...

  4. Growth-stage dependent crop yield response to ozone exposure.

    Science.gov (United States)

    Younglove, T; McCool, P M; Musselman, R C; Kahl, M E

    1994-01-01

    Data from four crop yield-loss field trials were examined to determine if analysis using an imposed phenological weighting function based on seasonal growth stage would provide a more accurate indication of impact of ozone exposure. Alfalfa (Medicago sativa L. cv. Moapa 69), dry bean (Phaseolus vulgaris L. cv. California Dark Red kidney), fresh market and processing tomato (Lycopersicon esculentum Mill. cv. 6718 VF and VF-145-B7879, respectively) were grown at 9-11 ambient field plots within southern California comprising an ambient gradient of ozone. The growing season for each crop was artificially divided into 'quarters' composed of equal numbers of whole days and roughly corresponding to specific growth stages. Ozone exposure was calculated for each of these 'quarters' and regressed against final crop yield using 163 different exposure statistics. Weighting functions were developed using reciprocal residual mean square (1/RMS) or percentage of the best 100 exposure statistics of the 163 tested (TOP100) for each of the quarters. The third quarter of the alfalfa season was clearly most responsive to ozone as measured by both of the weighting functions. Third quarter ozone was also weighted highest by both weighting functions for dry bean. Fresh market and processing tomato were each influenced the greatest by second quartero zone as demonstrated by both weighting functions. The occurrence of ozone during physiologically important events (flowering and initial fruit set in second quarter for tomato; pod development in third quarter for dry bean) appeared to influence the yield of these crops the greatest. Growth-stage-dependent phenological weighting of pollutant exposure may result in more effective predictions of levels of ozone exposure resulting in yield reductions.

  5. Comparative feedstock analysis in Setaria viridis L. as a model for C4 bioenergy grasses and Panicoid crop species

    Directory of Open Access Journals (Sweden)

    Carloalberto ePetti

    2013-06-01

    Full Text Available Second generation feedstocks for bioethanol will likely include a sizable proportion of perennial C4 grasses, principally in the Panicoideae clade. The Panicoideae contain agronomically important annual grasses including Zea mays L. (maize, Sorghum bicolor (L. Moench (sorghum, and Saccharum officinarum L. (sugar cane as well as promising second generation perennial feedstocks including Miscanthus x giganteus and Panicum virgatum L. (switchgrass. The underlying complexity of these polyploid grass genomes is a major limitation for their direct manipulation and thus driving a need for rapidly cycling comparative model. Setaria viridis (green millet is a rapid cycling C4 Panicoid grass with a relatively small and sequenced diploid genome and abundant seed production. Stable, transient and protoplast transformation technologies have also been developed for S. viridis making it a potentially excellent model for other C4 bioenergy grasses. Here, the lignocellulosic feedstock composition, cellulose biosynthesis inhibitor (CBI response and saccharification dynamics of S. viridis are compared with the annual s00orghum and maize and the perennial switchgrass bioenergy crops as a baseline study into the applicability for translational research. A genome-wide systematic investigation of the cellulose synthase-A (CesA genes was performed identifying eight candidate sequences. Two-developmental stages; a metabolically active young tissue and b metabolically plateaued (mature material are examined to compare biomass performance metrics.

  6. Biosolarization in garlic crop

    Science.gov (United States)

    Fabeiro, Concepcion; Andres, Manuela; Wic, Consuelo

    2014-05-01

    One of the most important limitations of garlic cultivation is the presence of various soil pathogens. Fusarium proliferatum and Sclerotinium cepivorum and nematode Ditilenchus dipsaci cause such problems that prevent the repetition of the crop in the same field for at least 5 -8 years or soil disinfection is necessary. Chemical disinfection treatments have an uncertain future, in the European Union are reviewing their use, due to the effect on the non-pathogenic soil fauna. This situation causes a itinerant cultivation to avoid the limitations imposed by soil diseases, thereby increasing production costs. The Santa Monica Cooperative (Albacete, Spain) requested advice on possible alternative techniques, solarization and biosolarization. For which a trial was conducted to evaluate the effectiveness on the riverside area of the municipality. This place has recently authorized irrigation, which would allow the repeated cultivation of garlic if the incidence of soil diseases and the consequent soil fatigue could be avoided. Additionally, this work will serve to promote the cultivation of organic garlic. Last, but not least, the biosolarization technique allows to use waste from wineries, oil mills and mushroom crops. (Bello et al. 2003). The essay should serve as demonstrative proof for farmers' cooperative members. The specific objective for this first year is to assess, the effect on the global soil biota, on the final garlic production and quality and the effect of biosolarization to control soil pathogens. The trial is set on a cooperative's plot previously cultivated with corn. 5 treatments were set, defined by different amounts of organic matter applied, 7.5, 5, 2.5 kg m -2, a solarized with no organic matter, and a control without any treatment. The plot has inground sprinkler for full coverage with four sprinkler lines demarcating the five bands of differential treatment, randomly arranged. Organic matter was incorporated the August 14, 2013, then thoroughly

  7. CropSAT

    OpenAIRE

    Söderström, Mats; Stadig, Henrik; Nissen, Knud; Piikki, Kristin

    2015-01-01

    Vi utvecklade CropSAT, ett webbaserat system för tillhandahållande av satellitdata över åkermarken där tilldelningsfiler kan laddas ned och användas för styrning av gödselspridare. Systemet testades under 2014 och vidareutvecklades under 2015 inom ramen för Greppa Näringen. Vår slutsats är att satellitdata som omräknats till vegetationsindexkartor kan användas i praktiken för anpassning av kvävegivan inom fält. Det är ett mycket kostnadseffektivt sätt att skapa underlag för bättre kvävehushål...

  8. Dry matter production of perennial pasture Tifton 85 (Cynodon spp under different doses of fertilization

    Directory of Open Access Journals (Sweden)

    Karlize Prigol

    2012-12-01

    Full Text Available Dairy farming is an activity that provides the small rural farmer the opportunity to earn income in small areas of land. The perennial pastures represent a source for a cheap and nutritious diet for the animals. The correct management of perennial pastures can be the key to sustainability in the dairy business, resulting in the preservation or recovery of the balance of a pasture system, starting with the pursuit of production with low costs and good pasture production per unit area. The correct choice of fertilizer is of great importance to ensure the continuous production of pasture both in quantity and in quality. The aim of this study was to evaluate the dry matter production of perennial pasture consisting of Tifton 85 (Cynodon spp under different nutrient sources on a typical dystrophic Red Latosol, presents in a region where the climate is characterized as humid-mesothermic with a hot summer, Cfa according to Köppen, with an average annual rainfall of 2039 mm, well distributed throughout the year and average annual temperatures around 18 º C, varying monthly from 14.1 to 23 º C. The treatments consisted of three nutrient sources: 1 organic manure, a base of chicken bedding (average values of reference NPK (02/03/02, 2 organic manure + mineral - organic mineral, with application of 606 kg ha-1 (04/10/10 Formula, aiming to adjust the same amounts of NPK supplied by mineral fertilizer and, 3 Mineral. The experimental design was a randomized blocks with nine replications. We collected five samples of each pasture treatment for determination of the average. After cutting the pasture of Tifton 85, the samples were subjected to weighing for determination of wet weight and then taken to the drying oven (temperature 65 ° C for 72 hours to determine dry matter production. The statistical analysis was performed with SAS for Windows computer system (SAS and the results submitted to the Tukey test at 5%. The highest dry matter yield (kg ha-1 was

  9. Invasion of non-native grasses causes a drop in soil carbon storage in California grasslands

    Energy Technology Data Exchange (ETDEWEB)

    Koteen, Laura E; Harte, John [Energy and Resources Group, 310 Barrows Hall, University of California, Berkeley, CA 94720 (United States); Baldocchi, Dennis D, E-mail: lkoteen@berkeley.edu [Department of Environmental Science, Policy and Management, 137 Mulford Hall, University of California, Berkeley, CA 94720 (United States)

    2011-10-15

    Vegetation change can affect the magnitude and direction of global climate change via its effect on carbon cycling among plants, the soil and the atmosphere. The invasion of non-native plants is a major cause of land cover change, of biodiversity loss, and of other changes in ecosystem structure and function. In California, annual grasses from Mediterranean Europe have nearly displaced native perennial grasses across the coastal hillsides and terraces of the state. Our study examines the impact of this invasion on carbon cycling and storage at two sites in northern coastal California. The results suggest that annual grass invasion has caused an average drop in soil carbon storage of 40 Mg/ha in the top half meter of soil, although additional mechanisms may also contribute to soil carbon losses. We attribute the reduction in soil carbon storage to low rates of net primary production in non-native annuals relative to perennial grasses, a shift in rooting depth and water use to primarily shallow sources, and soil respiratory losses in non-native grass soils that exceed production rates. These results indicate that even seemingly subtle land cover changes can significantly impact ecosystem functions in general, and carbon storage in particular.

  10. Irrigation modeling with AquaCrop

    Science.gov (United States)

    AquaCrop is a crop water productivity model developed by the Land and Water Division of UN-FAO. It simulates yield response to water of herbaceous crops, and is suited to address conditions where water is a key limiting factor in crop production. AquaCrop attempts to balance accuracy, simplicity, an...

  11. Genetic Engineering and Crop Production.

    Science.gov (United States)

    Jones, Helen C.; Frost, S.

    1991-01-01

    With a spotlight upon current agricultural difficulties and environmental dilemmas, this paper considers both the extant and potential applications of genetic engineering with respect to crop production. The nonagricultural factors most likely to sway the impact of this emergent technology upon future crop production are illustrated. (JJK)

  12. Crop Protection in Medieval Agriculture

    NARCIS (Netherlands)

    Zadoks, J.C.

    2013-01-01

    Mediterranean and West European pre-modern agriculture (agriculture before 1600) was by necessity ‘organic agriculture’. Crop protection is part and parcel of this agriculture, with weed control in the forefront. Crop protection is embedded in the medieval agronomy text books but specialised section

  13. Effects of chicory/perennial ryegrass swards compared with perennial ryegrass swards on the performance and carcass quality of grazing beef steers.

    Directory of Open Access Journals (Sweden)

    Christina L Marley

    Full Text Available An experiment investigated whether the inclusion of chicory (Cichorium intybus in swards grazed by beef steers altered their performance, carcass characteristics or parasitism when compared to steers grazing perennial ryegrass (Lolium perenne. Triplicate 2-ha plots were established with a chicory/ryegrass mix or ryegrass control. Forty-eight Belgian Blue-cross steers were used in the first grazing season and a core group (n = 36 were retained for finishing in the second grazing season. The experiment comprised of a standardisation and measurement period. During standardisation, steers grazed a ryegrass/white clover pasture as one group. Animals were allocated to treatment on the basis of liveweight, body condition and faecal egg counts (FEC determined 7 days prior to the measurement period. The measurement period ran from 25 May until 28 September 2010 and 12 April until 11 October 2011 in the first and second grazing year. Steers were weighed every 14 days at pasture or 28 days during housing. In the first grazing year, faecal samples were collected for FEC and parasite cultures. At the end of the first grazing year, individual blood samples were taken to determine O. ostertagi antibody and plasma pepsinogen levels. During winter, animals were housed as one group and fed silage. In the second grazing year, steers were slaughtered when deemed to reach fat class 3. Data on steer performance showed no differences in daily live-weight gain which averaged 1.04 kg/day. The conformation, fat grade and killing out proportion of beef steers grazing chicory/ryegrass or ryegrass were not found to differ. No differences in FEC, O. ostertagi antibody or plasma pepsinogen levels of beef steers grazing either chicory/ryegrass or ryegrass were observed. Overall, there were no detrimental effects of including chicory in swards grazed by beef cattle on their performance, carcass characteristics or helminth parasitism, when compared with steers grazing ryegrass.

  14. Effects of chicory/perennial ryegrass swards compared with perennial ryegrass swards on the performance and carcass quality of grazing beef steers.

    Science.gov (United States)

    Marley, Christina L; Fychan, Rhun; Davies, John W; Scollan, Nigel D; Richardson, R Ian; Theobald, Vince J; Genever, Elizabeth; Forbes, Andy B; Sanderson, Ruth

    2014-01-01

    An experiment investigated whether the inclusion of chicory (Cichorium intybus) in swards grazed by beef steers altered their performance, carcass characteristics or parasitism when compared to steers grazing perennial ryegrass (Lolium perenne). Triplicate 2-ha plots were established with a chicory/ryegrass mix or ryegrass control. Forty-eight Belgian Blue-cross steers were used in the first grazing season and a core group (n = 36) were retained for finishing in the second grazing season. The experiment comprised of a standardisation and measurement period. During standardisation, steers grazed a ryegrass/white clover pasture as one group. Animals were allocated to treatment on the basis of liveweight, body condition and faecal egg counts (FEC) determined 7 days prior to the measurement period. The measurement period ran from 25 May until 28 September 2010 and 12 April until 11 October 2011 in the first and second grazing year. Steers were weighed every 14 days at pasture or 28 days during housing. In the first grazing year, faecal samples were collected for FEC and parasite cultures. At the end of the first grazing year, individual blood samples were taken to determine O. ostertagi antibody and plasma pepsinogen levels. During winter, animals were housed as one group and fed silage. In the second grazing year, steers were slaughtered when deemed to reach fat class 3. Data on steer performance showed no differences in daily live-weight gain which averaged 1.04 kg/day. The conformation, fat grade and killing out proportion of beef steers grazing chicory/ryegrass or ryegrass were not found to differ. No differences in FEC, O. ostertagi antibody or plasma pepsinogen levels of beef steers grazing either chicory/ryegrass or ryegrass were observed. Overall, there were no detrimental effects of including chicory in swards grazed by beef cattle on their performance, carcass characteristics or helminth parasitism, when compared with steers grazing ryegrass. PMID:24489708

  15. Using the Model Perennial Grass Brachypodium sylvaticum to Engineer Resistance to Multiple Abiotic Stresses

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, Sean; Reguera, Maria; Sade, Nir; Cartwright, Amy; Tobias, Christian; Thilmony, Roger; Blumwald, Eduardo; Vogel, John

    2015-03-20

    We are using the perennial model grass Brachypodium sylvaticum to identify combinations of transgenes that enhance tolerance to multiple, simultaneous abiotic stresses. The most successful transgene combinations will ultimately be used to create improved switchgrass (Panicum virgatum L.) cultivars. To further develop B. sylvaticum as a perennial model grass, and facilitate our planned transcriptional profiling, we are sequencing and annotating the genome. We have generated ~40x genome coverage using PacBio sequencing of the largest possible size selected libraries (18, 22, 25 kb). Our initial assembly using only long-read sequence contained 320 Mb of sequence with an N50 contig length of 315 kb and an N95 contig length of 40 kb. This assembly consists of 2,430 contigs, the largest of which was 1.6 Mb. The estimated genome size based on c-values is 340 Mb indicating that about 20 Mb of presumably repetitive DNA remains yet unassembled. Significantly, this assembly is far superior to an assembly created from paired-end short-read sequence, ~100x genome coverage. The short-read-only assembly contained only 226 Mb of sequence in 19k contigs. To aid the assembly of the scaffolds into chromosome-scale assemblies we produced an F2 mapping population and have genotyped 480 individuals using a genotype by sequence approach. One of the reasons for using B. sylvaticum as a model system is to determine if the transgenes adversely affect perenniality and winter hardiness. Toward this goal, we examined the freezing tolerance of wild type B. sylvaticum lines to determine the optimal conditions for testing the freezing tolerance of the transgenics. A survey of seven accessions noted significant natural variation in freezing tolerance. Seedling or adult Ain-1 plants, the line used for transformation, survived an 8 hour challenge down to -6 oC and 50% survived a challenge down to -9 oC. Thus, we will be able to easily determine if the transgenes compromise freezing tolerance. In the

  16. Genomic Variance Estimation Based on Genotyping-by-Sequencing with Different Coverage in Perennial Ryegrass

    DEFF Research Database (Denmark)

    Ashraf, Bilal; Fé, Dario; Jensen, Just;

    2014-01-01

    Advancement in next generation sequencing (NGS) technologies has significantly decreased the cost of DNA sequencing enabling increased use of genotyping by sequencing (GBS) in several plant species. In contrast to array-based genotyping GBS also allows for easy estimation of allele frequencies...... at each SNP in family pools or polyploids. There are, however, several statistical challenges associated with this method, including low sequencing depth and missing values. Low sequencing depth results in inaccuracies in estimates of allele frequencies for each SNP. In this work we have focused...... on optimizing methods and models utilizing F2 family phenotype records and NGS information from F2 family pools in perennial ryegrass. Genomic variance was estimated using genomic relationship matrices based on different coverage depths to verify effects of coverage depth. Example traits were seed yield, rust...

  17. Influence of perennial plants on chemical properties of arid calcareous soils in Iran

    Energy Technology Data Exchange (ETDEWEB)

    Karimian, N.; Razmi, K. (Shiraz Univ. (Iran))

    1990-10-01

    The authors conducted a study in Bajgah to determine the influence of perennial plants on some selected properties of soils formed on the highly calcareous parent material. The major plant genera were determined to be Agropyron, Artemisia, Astragalus, Dianthus, Eryngium, Peganum, Polygonum, Stipa, and Thymus. Tops of plants genera were found to be significantly different in ash, N, P, K, Ca, Mg, Na, Mn, Zn, and Cu; the concentration of Fe was not significantly different. The authors found the plants to differ significantly in their influence on soil properties. Peganum caused an accumulation of organic matter (OM) as high as 7% in the soil, in an environment where the soils typically contain less than 1% OM. Soil concentrations of P, K, Mn, Zn, and Cu were also found to vary significantly beneath different plant genera. They suggest these differences in OM accumulation were caused by plant litter. Concentration of Fe in the soils formed beneath different plant genera was statistically unchanged.

  18. Nasal inhalation of budesonide from a spacer in children with perennial rhinitis and asthma

    DEFF Research Database (Denmark)

    Pedersen, W; Hjuler, Inga Merete; Bisgaard, H;

    1998-01-01

    The standard treatment of allergic rhinitis and asthma consists of topical corticosteroids administered intranasally and inhaled through the mouth. Although this therapy is highly effective, and side-effects are few and mild, it may be possible further to improve the therapeutic index and patient...... compliance with the treatment. In the present study, we evaluated a nasal inhalation system used for the simultaneous treatment of rhinitis and asthma. In principle, it results in an airway deposition of the corticosteroid similar to that of inhaled allergens. Twenty-four children with perennial rhinitis and...... asthma inhaled budesonide through the nose from a pressurized aerosol, attached to a spacer device, in a double-blind, placebo-controlled, crossover study. Compared with placebo, budesonide treatment resulted in a significant reduction of nasal symptoms (P<0.01) and of asthma symptoms (P<0.05), and in an...

  19. Characterization of gene expression associated with drought avoidance and tolerance traits in a perennial grass species.

    Directory of Open Access Journals (Sweden)

    Peng Zhou

    Full Text Available To understand molecular mechanisms of perennial grass adaptation to drought stress, genes associated with drought avoidance or tolerance traits were identified and their expression patterns were characterized in C4 hybrid bermudagrass [Cynodon dactylon (L. Pers.×C. transvaalensis Burtt Davy, cv. Tifway] and common bermudagrass (C. dactylon, cv. C299. Plants of drought-tolerant 'Tifway' and drought-sensitive 'C299' were exposed to drought for 5 d (mild stress and 10 d (severe stress by withholding irrigation in a growth chamber. 'Tifway' maintained significantly lower electrolyte leakage and higher relative water content than 'C299' at both 5 and 10 d of drought stress. Four cDNA libraries via suppression subtractive hybridization analysis were constructed and identified 277 drought-responsive genes in the two genotypes at 5 and 10 d of drought stress, which were mainly classified into the functional categories of stress defense, metabolism, osmoregulation, membrane system, signal and regulator, structural protein, protein synthesis and degradation, and energy metabolism. Quantitative-PCR analysis confirmed the expression of 36 drought up-regulated genes that were more highly expressed in drought-tolerant 'Tifway' than drought-sensitive 'C299', including those for drought avoidance traits, such as cuticle wax formation (CER1 and sterol desaturase, for drought tolerance traits, such as dehydration-protective proteins (dehydrins, HVA-22-like protein and oxidative stress defense (superoxide dismutase, dehydroascorbate reductase, 2-Cys peroxiredoxins, and for stress signaling (EREBP-4 like protein and WRKY transcription factor. The results suggest that the expression of genes for stress signaling, cuticle wax accumulation, antioxidant defense, and dehydration-protective protein accumulation could be critically important for warm-season perennial grass adaptation to long-term drought stress.

  20. Temperature Effects on the Seed Germination of Some Perennial and Annual Species of Asteraceae Family

    Directory of Open Access Journals (Sweden)

    Zarghani Hadi

    2014-12-01

    Full Text Available Temperature is the most critical factor determining success or failure of plant establishment. Seed germination response of five medicinal species include three seed-propagated perennial species, Cichorium intybus, cynara scolymus and Echinacea purpurea and vegetative-reproduction perennial species, Achillea millefolium and annual species, Matricaria aurea were assessed at constant temperatures. The seeds were exposed to constant temperatures of 5, 10, 15, 20, 25, 30, 35, 40 and 45°C under total darkness. Germination percentage of all the species were significantly affected by various temperatures (p ≤ 0.001. A. millefolium did not germinate at 5-10 and 35-45°C, but showed noticeable germination percentage (73.3-100% at temperatures ranged from 15-30° C. The highest total germination percentage was observed within the range of 15-35 °C for other species. Also, we calculated cardinal temperatures (the minimum, optimum and maximum temperature for seed germination of species. The highest value for minimum temperature was 10.07ºC in A. millefolium followed by C. scolymus and M. aurea (5ºC while the lowest was for E. purpurea and C. intybus (2.68 and 2.90ºC respectively. The lowest value for optimum temperature was detected in A. millefolium (22.72ºC and M. aurea (23.88°C while the maximum values were observed in E. purpurea and C. intybus (30.40ºC and 29.90ºC respectively. Based on results of present study we concluded that species with both vegetative and seed-propagated reproduction forms like A. millefolium had smaller temperature range rather those with just one way of reproduction (seed production.

  1. Diversity of cultured bacteria from the perennial ice block of Scarisoara Ice Cave, Romania

    Directory of Open Access Journals (Sweden)

    Corina Iţcuş

    2016-01-01

    Full Text Available Cave ice ecosystems represent a poorly investigated glacial environment. Diversity of cave ice bacteria and their distribution in perennial ice deposits of this underground glacial habitat could constitute a proxy for microbial response to climatic and environmental changes. Scarisoara Ice Cave (Romania hosts one of the oldest and largest cave ice blocks worldwide. Here we report on cultured microbial diversity of recent, 400, and 900 years-old perennial ice from this cave, representing the first characterization of a chronological distribution of cave-ice bacteria. Total cell density measured by SYBR Green I epifluorescence microscopy varied in the 2.4 x 104 – 2.9 x 105 cells mL-1 range. The abundance of cultured bacteria (5 x 102 – 8 x 104 CFU mL-1 representing 0.3-52% of the total cell number decreased exponentially with the ice age, and was higher in organic rich ice sediments. Cultivation at 4˚C and 15˚C using BIOLOG EcoPlates revealed a higher functional diversity of cold-active bacteria, dependent on the age, sediment content and physicochemical properties of the ice. The composition dissimilarity of ice microbiota across the ice block was confirmed by growth parameter variations when cultivated in different liquid media at low and high temperatures. PCR-DGGE and sequencing of bacterial 16S rRNA gene fragments from the cultured ice samples led to the identification of 77 bacterial amplicons belonging to Gammaproteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, showing variation in distribution across the ice layers. Several identified OTUs were homologous to those identified in other glacial and karst environments and showed partial conservation across the ice block. Moreover, our survey provided a glimpse on the cave-ice hosted bacteria as putative biomarkers for past climate and environmental changes.

  2. Holocene climate variability and anthropogenic impacts from Lago Paixban, a perennial wetland in Peten, Guatemala

    Science.gov (United States)

    Wahl, David B.; Hansen, Richard D.; Byrne, Roger; Anderson, Lysanna; Schreiner, T.

    2016-01-01

    Analyses of an ~ 6 m sediment core from Lago Paixban in Peten, Guatemala, document the complex evolution of a perennial wetland over the last 10,300 years. The basal sediment is comprised of alluvial/colluvial fill deposited in the early Holocene. The absence of pollen and gastropods in the basal sediments suggests intermittently dry conditions until ~ 9000 cal yr. BP (henceforth BP) when the basin began to hold water perennially. Lowland tropical forest taxa dominated the local vegetation at this time. A distinct band of carbonate dating to ~ 8200 BP suggests regionally dry conditions, possibly associated with the 8.2 ka event. Wetter conditions during the Holocene Thermal Maximum are indicated by evidence of a raised water level and an open water lake. The timing of this interval coincides with strengthening of the Central American Monsoon. An abrupt change at 5500 BP involved the development of a sawgrass marsh and onset of peat deposition. The lowest recorded water levels date to 5500–4500 BP. Pollen, isotope, geochemical, and sedimentological data indicate that the coring site was near the edge of the marsh during this period. A rise in the water table after 4500 BP persisted until around 3500 BP. Clay marl deposition from 3500 to 210 BP corresponds to the period of Maya settlement. An increase in δ13C, the presence of Zea pollen, and a reduction in the percentage of forest taxa pollen indicate agricultural activity at this time. In contrast to several nearby paleoenvironmental studies, proxy evidence from Lago Paixban indicates human presence through the Classic/Postclassic period transition (~ 1000 BP) and persisting until the arrival of Europeans. Cessation of human activity around 210 BP resulted in local afforestation and the re-establishment of the current sawgrass marsh at Lago Paixban.

  3. New Methodology for Quantifying the Effects of Perennials on Their Patch Productivity in Semi-arid Environments

    Science.gov (United States)

    Mor-Mussery, Amir; Leu, Stefan; Budovsky, Arie

    2015-05-01

    The correlations between perennials and the herbaceous productivity in patches occupied by them were previously studied and several descriptive models were defined. Yet these studies focused on either single or several species without analyzing higher numbers and ranking their effects. Here we describe a handy analytical methodology which allows separating the effects of each perennial species on herbaceous productivity at its respective patches from those of the others in a given area, even in case of complex patches containing several species. The described methodology also allows analysts to correlate the effect of perennials to their patch sizes and the respective herbaceous biomass. Additional mathematical analysis presented here succeeded in differentiating between the perennial species stand-alone presence effect on the herbaceous productivity and that attributed to the canopy size. In addition, the effects of location along the slope and its rockiness outlines were studied. As a case study, we chose representative sloped shrubland with rockiness outlines, located in Yattir farm, Northern Negev, Israel. Based on the described analyses we found that the species with the highest positive effects on the herbaceous productivity were Echinops polyceras, Echium angustifolium, and Salvia lanigera. Contradictory effects were observed in case of Thymelea hirsute, Anchusa ramosus, and Noaea mucronata. Collectively, the presented methodology could be an important management tool for monitoring the herbaceous biomass amounts in a given shrubland.

  4. Dry matter yields and hydrological properties of three perennial grasses of a semi-arid environment in East Africa

    NARCIS (Netherlands)

    Mganga, K.Z.; Musimba, N.K.R.; Nyariki, D.M.; Nyangito, M.M.; Mwangombe, A.W.; Ekaya, W.N.; Clavel, D.; Francis, J.; Kaufmann, Von R.; Verhagen, J.; Muiri, W.M.

    2010-01-01

    Enteropogon macrostachyus (Bush rye), Cenchrus ciliaris L. (African foxtail grass) and Eragrostis superba Peyr (Maasai love grass) are important perennial rangeland grasses in Kenya. They provide an important source of forage for domestic livestock and wild ungulates. These grasses have been used ex

  5. Improved fructan accumulation in perennial ryegrass transformed with the onion fructosyltransferase genes 1-SST and 6G-FFT

    DEFF Research Database (Denmark)

    Gadegaard, Gitte; Didion, Thomas; Foiling, Marianne;

    2008-01-01

    value of ryegrass (Lolium perenne) by increasing the fructan content through expression of heterologous fructan biosynthetic genes. We developed perennial ryegrass Lines expressing sucrose:sucrose 1-fructosyltransferase and fructan:fructan 6G-fructosyltransferase genes from onion (Allium cepa) which...

  6. 30 CFR 817.57 - Hydrologic balance: Surface activities in or adjacent to perennial or intermittent streams.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Hydrologic balance: Surface activities in or adjacent to perennial or intermittent streams. 817.57 Section 817.57 Mineral Resources OFFICE OF SURFACE... PERMANENT PROGRAM PERFORMANCE STANDARDS-UNDERGROUND MINING ACTIVITIES § 817.57 Hydrologic balance:...

  7. Expressed sequence tag-derived microsatellite markers of perennial ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Studer, Bruno; Asp, Torben; Frei, Ursula;

    2008-01-01

    An expressed sequence tag (EST) library of the key grassland species perennial ryegrass (Lolium perenne L.) has been exploited as a resource for microsatellite marker development. Out of 955 simple sequence repeat (SSR) containing ESTs, 744 were used for primer design. Primer amplification was te...

  8. ON-FARM PRETREATMENT TECHNOLOGIES FOR IMPROVING ENZYMATIC DIGESTIBILITY OF CELLULOSE AND HEMICELLULOSE PRESENT IN PERENNIAL GRASS AND CORN STOVER

    Science.gov (United States)

    Recently, wet storage methods have been proposed for feedstock preservation and on-farm storage of perennial grass and corn stover biomass. The advantages over a dry storage system include lower risk of fire, reduced harvest costs, and improved feedstock susceptibility to enzymatic hydrolysis. We ...

  9. Water and nitrogen in crop and pasture systems in southern Australia

    International Nuclear Information System (INIS)

    Recent research on water and N for dryland crops in southern Australia has addressed the need for more efficient and sustainable production. Water-use efficiency is well below the potential and N-use efficiency well below optimum on farms. Excess water and N cause on-site and off-site environmental damage. The most effective means of illustrating these inefficiencies to growers is to present simple benchmarks of water and N-use efficiencies with which farmers can assess and improve the performance of their own crops. The practices shown by our recent research that best support the goals of more efficient and sustainable production are those that maximize extraction of soil water and mineral N, and increase biological N2 fixation. Wheat growing after a brassica break-crop extract more water and mineral N from the soil than when grown as a continuous cereal, apparently because of a 'biofumigation' effect that reduces the numbers of soil-borne pathogens of wheat and produces a stronger root system. In the case of phased pasture-crop systems, annual pastures do not fully extract subsoil water or mineral N. However, when the grasses are removed from annual pastures with a selective herbicide, the remaining pure clover rapidly decomposes after maturity, leaving a large amount of mineral N for the following crop. Perennial pastures containing lucerne produce more forage and fix more N2 than do annual pastures, but they dry the soil profile. After removal of the lucerne, the soil may be so dry that mineralization is slow, with the risk of water deficit for the subsequent crop. (author)

  10. Evaluation of the Community Land Model (CLM-Crop) in the United States Corn Belt

    Science.gov (United States)

    Chen, M.; Griffis, T.

    2013-12-01

    An accurate representation of crop phenology in land surface models is crucial for predicting the carbon, water and energy budgets of managed ecosystems. Soybean and corn are cultivated in approximately 600,000 km2 in the Corn Belt- an area greater than the entire State of California. Accurate prediction of the radiation, energy, and carbon budgets of this region is especially important for understanding its influence on radiative forcing, the thermodynamic properties of the atmospheric boundary layer, and changes in climate. Recently, key algorithms describing crop biophysics and interactive crop management (planting, fertilization, irrigation, harvesting) have been implemented in the Community Land Model (CLM-Crop). CLM-Crop provides a framework for prognostic simulation of crop phenology and evaluation of human management decisions under future climate scenarios. However, there is an important need to evaluate CLM-Crop against a broad range of agricultural site observations in order to understand its limitations and to help optimize the crop biophysical parameterization. Here we evaluated CLM-Crop version 4.5 at 9 AmeriFlux corn/soybean sites that are located within the United States Corn Belt. The following questions were addressed: 1) How well does CLM perform for the 9 crop sites with different management techniques (e.g., tillage vs. no-till, rainfed vs. irrigated)? 2) What are the model's strengths and weaknesses of simulating crop phenology, energy fluxes and carbon fluxes? 3) What steps are needed in order to improve the reliability of the CLM-Crop simulations? Our preliminary results indicate that CLM-Crop can simulate the radiation, energy, and carbon fluxes with reasonable accuracy during the mid growing season. The model performance degrades substantially during the early and late growing seasons, which we attribute to a bias in crop phenology. For instance, we observed that the simulated corn and soybean phenology (LAI) has an earlier phase than the

  11. 75 FR 59057 - Common Crop Insurance Regulations, Cotton Crop Insurance Provisions and Macadamia Nut Crop...

    Science.gov (United States)

    2010-09-27

    ... March 30, 2010 (75 FR 15778-15891). Need for Correction As published, the final regulation contained... Provisions and Macadamia Nut Crop Insurance Provisions; Correction AGENCY: Federal Crop Insurance Corporation... make corrections relating to the insurance of cotton and macadamia nuts that published March 30,...

  12. The California Hazards Institute

    Science.gov (United States)

    Rundle, J. B.; Kellogg, L. H.; Turcotte, D. L.

    2006-12-01

    California's abundant resources are linked with its natural hazards. Earthquakes, landslides, wildfires, floods, tsunamis, volcanic eruptions, severe storms, fires, and droughts afflict the state regularly. These events have the potential to become great disasters, like the San Francisco earthquake and fire of 1906, that overwhelm the capacity of society to respond. At such times, the fabric of civic life is frayed, political leadership is tested, economic losses can dwarf available resources, and full recovery can take decades. A patchwork of Federal, state and local programs are in place to address individual hazards, but California lacks effective coordination to forecast, prevent, prepare for, mitigate, respond to, and recover from, the harmful effects of natural disasters. Moreover, we do not know enough about the frequency, size, time, or locations where they may strike, nor about how the natural environment and man-made structures would respond. As California's population grows and becomes more interdependent, even moderate events have the potential to trigger catastrophes. Natural hazards need not become natural disasters if they are addressed proactively and effectively, rather than reactively. The University of California, with 10 campuses distributed across the state, has world-class faculty and students engaged in research and education in all fields of direct relevance to hazards. For that reason, the UC can become a world leader in anticipating and managing natural hazards in order to prevent loss of life and property and degradation of environmental quality. The University of California, Office of the President, has therefore established a new system-wide Multicampus Research Project, the California Hazards Institute (CHI), as a mechanism to research innovative, effective solutions for California. The CHI will build on the rich intellectual capital and expertise of the Golden State to provide the best available science, knowledge and tools for

  13. Agronomic Suitability of Bioenergy Crops in Mississippi

    Energy Technology Data Exchange (ETDEWEB)

    Lemus, Rocky; Baldwin, Brian; Lang, David

    2011-10-01

    ‚€Ã‚¢ How will these crops affect fertilizer use and water quality? • What kind of water management is needed to maintain a productive crop? The answers to these questions will help supporting institutions across the state to improve land assessment and agronomic management practices for biomass production. In the last decade, energy supply has become a worldwide problem. Bioenergy crops could supply energy in the future. Bioenergy crops are plants, usually perennial grasses and trees, that produce a lot of biomass that can be converted into energy. Bioenergy crops can be grown for two energy markets: power generation, such as heat and electricity, or liquid fuel, such as cellulosic ethanol. These resources could reduce petroleum dependency and greenhouse gas production. Woody plants and herbaceous warm-season grasses, such as switchgrass, giant miscanthus,energy cane, and high yielding sorghums, could be major sources of biomass in Mississippi.

  14. Habitat requirements of the endangered California freshwater shrimp (Syncaris pacifica) in lagunitas and Olema creeks, Marin County, California, USA

    Science.gov (United States)

    Martin, Barbara A.; Saiki, Michael K.; Fong, Darren

    2009-01-01

    This study was conducted to better understand the habitat requirements and environmental limiting factors of Syncaris pacifica, the California freshwater shrimp. This federally listed endangered species is native to perennial lowland streams in a few watersheds in northern California. Field sampling occurred in Lagunitas and Olema creeks at seasonal intervals from February 2003 to November 2004. Ten glides, five pools, and five riffles served as fixed sampling reaches, with eight glides, four pools, and four riffles located in Lagunitas Creek and the remainder in Olema Creek. A total of 1773 S. pacifica was counted during this study, all of which were captured along vegetated banks in Lagunitas Creek. Syncaris pacifica was most numerous in glides (64), then in pools (31), and lastly in riffles (5). According to logistic regression analysis, S. pacifica was mostly associated with submerged portions of streambank vegetation (especially overhanging vegetation such as ferns and blackberries, emergent vegetation such as sedge and brooklime, and fine roots associated with water hemlock, willow, sedge, and blackberries) along with low water current velocity and a sandy substrate. These seemingly favorable habitat conditions for S. pacifica were present in glides and pools in Lagunitas Creek, but not in Olema Creek. ?? 2009 The Crustacean Society.

  15. Senior Research Connects Students with a Living Laboratory As Part of an Integrated Crop and Livestock System

    Science.gov (United States)

    Senturklu, Songul; Landblom, Douglas; Brevik, Eric C.

    2015-04-01

    Soil, water, soil microbes, and solar energy are the main sources that sustain life on this planet. Without them working in concert, neither plants nor animals would survive. Considering the efficiency of animal production targets, soil must be protected and improved. Therefore, through our sustainable integrated crop and livestock research, we are studying animal and soil interactions from the soil to the plate. Integrating beef cattle systems into a diverse cropping system is providing a living laboratory for education beyond the traditional classroom setting. To establish the living learning laboratory at the Dickinson Research Extension Center, a five-crop rotation was established that included adapted cool and warm season grasses and broadleaf crops. The crop rotation is: sunflower > hard red spring wheat > fall seeded winter triticale-hairy vetch (hay)/spring seeded 7-species cover crop > Corn (85-95 day varieties) > field pea-barley intercrop. Sunflower and spring wheat are harvested for cash crop income in the rotation. Livestock integration occurs when yearling steers that had previously grazed perennial pastures until mid-August graze field pea-barley and subsequently unharvested corn. Average grazing days for field pea-barley and unharvested corn is 30 and 70 days, respectively. At the end of the grazing period, the yearling steers average 499-544 kg and are moved to a feedlot and fed an additional 75 days until slaughter. Maximizing grazing days and extending the grazing season through integration with the cropping system reduces custom feeding costs and enhances animal profit. Beef cows do not require high quality feed after their calves have been weaned. Therefore, gestating beef cows are an ideal animal to graze cover crops and crop aftermath (residue) after yearling steer grazing and farming operations have been completed. Extending the grazing season for beef cows by grazing cover crops and residues reduces winter feed cost, which is one of the

  16. Genetically modified food crops and public health

    OpenAIRE

    Acosta Orlando; Chaparro Giraldo Alejandro

    2009-01-01

    The progress made in plant biotechnology has provided an opportunity to new food crops being developed having desirable traits for improving crop yield, reducing the use of agrochemicals and adding nutritional properties to staple crops. However, genetically modified (GM) crops have become a subject of intense debate in which opponents argue that GM crops represent a threat to individual freedom, the environment, public health and traditional economies. Despite the advances in food crop agric...

  17. Seasonal Soil Nitrogen Mineralization within an Integrated Crop and Livestock System in Western North Dakota, USA

    Science.gov (United States)

    Landblom, Douglas; Senturklu, Songul; Cihacek, Larry; Pfenning, Lauren; Brevik, Eric C.

    2015-04-01

    pipes were pressed into the soil as enclosures to restrict root access to soil nitrogen. Soil samples were taken as close to 2-week intervals as possible from both inside and outside the enclosures. The crop rotation N values were also compared to triple replicated perennial native grassland plot areas (predominate sp. Western wheatgrass - Pascopyrum smithii, Blue grama - Bouteloua gracilis, Little bluestem - Schizachyrium scoparium, Switchgrass - Panicum virgatum). Trends identified for both NH4-N and NO3-N indicate that the values are relatively similar with respect to seasonal change over time. There was a greater amount of soil nitrogen accumulation inside the enclosures indicating that outside the enclosures roots scavenge nitrogen for plant growth and production. Seasonally, comparing the cropping system crops, NO3-N declined mid-July and then rebounded by mid-August and continued to increase until leveling off in September. Corn NO3-N, however, did not follow this pattern, but increased from early June to the end of June and remained high until the first of September. We will present the results of bulk density data and seasonal N fertility data providing evidence for the impact of previous CC on corn production. Probable explanation for the mid-summer nitrogen decline will be presented and justification for reduced fertilizer application will be discussed.

  18. The Story of California = La Historia de California.

    Science.gov (United States)

    Bartel, Nick

    "The Story of California" is a history and geography of the state of California, intended for classroom use by limited-English-proficient, native Spanish-speaking students in California's urban middle schools. The book is designed with the left page in English and the right page in Spanish to facilitate student transition into comfortable use of…

  19. Recycling crop residues for use in recirculating hydroponic crop production

    Science.gov (United States)

    Mackowiak, C. L.; Garland, J. L.; Sager, J. C.

    1996-01-01

    As part of bioregenerative life support feasibility testing by NASA, crop residues are being used to resupply elemental nutrients to recirculating hydroponic crop production systems. Methods for recovering nutrients from crop residues have evolved from water soaking (leaching) to rapid aerobic bioreactor processing. Leaching residues recovered the majority of elements but it also recovered significant amounts of soluble organics. The high organic content of leachates was detrimental to plant growth. Aerobic bioreactor processing reduced the organic content ten-fold, which reduced or eliminated phytotoxic effects. Wheat and potato production studies were successful using effluents from reactors having with 8- to 1-day retention times. Aerobic bioreactor effluents supplied at least half of the crops elemental mass needs in these studies. Descriptions of leachate and effluent mineral content, biomass productivity, microbial activity, and nutrient budgets for potato and wheat are presented.

  20. Boron toxicity characteristics of four northern California endemic tree species

    Energy Technology Data Exchange (ETDEWEB)

    Glaubig, B.A.; Bingham, F.T.

    A greenhouse study was undertaken to determine the characteristics of soil B toxicity for four tree species endemic to The Geysers area in northern California: digger pine (Pinus sabiniana Dougl. ex D. Don), California laurel (or, California bay) (Umbellularia californica (Hoo. and Arn. Nutt.)), madrone (Arbutus menziesii Pursh), and bigleaf maple (Acer macrophyllum Pursh). Significant exponential relationships were found between soil B concentration and relative growth, and between tissue B concentration and relative growth for the four species. Significant linear relationships were found between both soil and tissue B concentration and foliar damage for the four species. Foliar damages over 25% of the leaf or needle area on digger pine, California laurel, madrone, and bigleaf maple, respectively, occurred at saturated soil extract concentrations (mmol B/L) of 1.2, 0.4, 0.5, and 0.08. Twenty-five percent foliar damage was associated with leaf or needle tissue concentrations (mmol B/kg) of 115, 100, 50, and 30 for the digger pine, California laurel, madrone, and bigleaf maple, respectively. Growth decrements of 25% occurred at saturated soil extract concentrations (mmol B/L) of 1.6, 0.3, 0.2, 0.5 for the digger pine, California laurel, madrone, and bigleaf maple, respectively. Twenty-five percent growth decrements were associated with leaf or needle tissue concentrations (mmol B/kg) of 140, 100, 20, and 7 for the digger pine, California laurel, madrone, and bigleaf maple, respectively. By comparison with two agronomic crops - cotton (Gossypium hirsutum L.) and cowpea (Vigna unguiculata L.) - the four tree species were placed into one of six B tolerance classes.

  1. Rice: The First Crop Genome.

    Science.gov (United States)

    Jackson, Scott A

    2016-12-01

    Rice was the first sequenced crop genome, paving the way for the sequencing of additional and more complicated crop genomes. The impact that the genome sequence made on rice genetics and breeding research was immediate, as evidence by citations and DNA marker use. The impact on other crop genomes was evident too, particularly for those within the grass family. As we celebrate 10 years since the completion of the rice genome sequence, we look forward to new empowering tool sets that will further revolutionize research in rice genetics and breeding and result in varieties that will continue to feed a growing population. PMID:27003180

  2. Oil crops: Status and outlook

    International Nuclear Information System (INIS)

    The worldwide expansion in the production of oil crops, the increase of the production of edible vegetable oils and of oil cake or meal in the past 50 years is presented. It is noted also that the imports of edible oil increased markedly, especially in developing countries. Plant breeding efforts have been the key to the tremendous increase in the production of oil crops. The need to devote more research and development efforts to the wide range of oil crops, to domesticate and develop species which can serve as new sources for existing or new requirements is emphasized. 9 refs, 7 tabs

  3. Water Use Efficiency for Establishing Biofuel Crops in Central Illinois

    Science.gov (United States)

    Bernacchi, C. J.; Zeri, M.; Hussain, M. Z.; Anderson-Teixeira, K. J.; Masters, M.; DeLucia, E. H.

    2012-12-01

    The production of biofuels from cellulosic plant material is expected to increase worldwide as countries look for alternative sources of energy. The choice of feedstocks suitable for ethanol production from cellulosic material must take into account several factors, such as productivity, response to local climate, and environmental impacts on the carbon, nitrogen and water cycles. With regards to the carbon cycle, the best options for biofuel crops are species that are highly productive in terms of harvestable biomass, but without depleting the soil carbon pools by requiring annual tillage before planting, as is the case of corn (Zea mays), the current dominant biofuel in the US. Perennial species such as miscanthus (Miscanthus × giganteus) and switchgrass (Panicum virgatum L.) have many advantages over annual crops due to the reduced use of fertilizer and less irrigation requirements relative to maize. The efficiency of plants in using water while accumulating biomass is an important factor when choosing the best biofuel crop to be planted in a certain location. Water use efficiency (WUE) is the term generally used to refer to the ratio of carbon accumulated over water used during a certain period of time. Water use efficiency is an important metric when cellulosic biofuels are considered, since it takes into account the benefits (carbon accumulated in soils or harvested) and the environmental impact (the use of water). This quantity is derived in many ways based on the metric of carbon for an ecosystem. Net ecosystem production (NEP) is the net balance of carbon derived from GPP - Re, where GPP is the gross primary production and Re is the ecosystem respiration. The ratio of NEP over total water used during the year (TWU) will be referred as EWUE, from "ecosystem" WUE. The value of EWUE represents ecological benefit of the feedstock, since it accounts for the carbon that might be accumulated in soils. Another metric is the HWUE, after "harvest" WUE, which

  4. Limited and time-delayed internal resource allocation generates oscillations and chaos in the dynamics of citrus crops

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Xujun, E-mail: yexujun@cc.hirosaki-u.ac.jp [College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058 (China); Faculty of Agriculture and Life Sciences, Hirosaki University, Aomori 036-8561 (Japan); Sakai, Kenshi, E-mail: ken@cc.tuat.ac.jp [Environmental and Agricultural Engineering Department, Tokyo University of Agriculture and Technology, Tokyo 183-8509 (Japan)

    2013-12-15

    Alternate bearing or masting is a yield variability phenomenon in perennial crops. The complex dynamics in this phenomenon have stimulated much ecological research. Motivated by data from an eight-year experiment with forty-eight individual trees, we explored the mechanism inherent to these dynamics in Satsuma mandarin (Citrus unshiu Marc.). By integrating high-resolution imaging technology, we found that the canopy structure and reproduction output of individual citrus crops are mutually dependent on each other. Furthermore, it was revealed that the mature leaves in early season contribute their energy to the fruiting of the current growing season, whereas the younger leaves show a delayed contribution to the next growing season. We thus hypothesized that the annual yield variability might be caused by the limited and time-delayed resource allocation in individual plants. A novel lattice model based on this hypothesis demonstrates that this pattern of resource allocation will generate oscillations and chaos in citrus yield.

  5. Archaeobotanical reconstructions of field habitats and crops: the grange in Pomorzany near Kutno, 18th/19th c.

    Directory of Open Access Journals (Sweden)

    Koszałka Joanna

    2015-03-01

    Full Text Available The paper presents the results of research of plant macrofossils from the grain deposit deriving from the 18th/19th centuries. The analysed material included 24760 diaspores representing 73 taxa. The majority were cultivated cereal crop species, and there was also abundance of accompanying segetal weed species. About 95% of the gathered crop material was Secale cereale. Another important crop was Hordeum vulgare and there were also some remains of Avena sativa, Triticum aestivum, Fagopyrum esculentum. Cannabis sativa and Linum usitatissimum were found as well. Weeds competing with these crops were, among others, the following species: Agrostemma githago, Raphanus raphanistrum, Apera spica-venti, Bromus secalinus, Centaurea cyanus, Spergula arvensis, Thlaspi arvense, Viola arvensis/tricolor, Fallopia convolvulus, Polygonum persicaria, Mentha arvensis, Anthemis arvensis, Papaver rhoeas, Rumex acetosella, Scleranthus annuus, Aphanes arvensis, Setaria pumila, Setaria viridis/verticilata. Extremely large presence of wild plant diaspores in the material allowed conducting economic and environmental interpretations. Reconstruction methods applied, used primarily in the case of macroremains from granaries, were fully applicable to the analysed plant residues. Weed species composition in the analysed material showed that they were mostly typical for the main winter crop. Some amount of species typical for other habitats were also found and they probably came from the near-by rye field. The presence of perennial diaspores indicated that the field was probably set aside

  6. Variations in pollinator density and impacts on large cardamom (Amomum subulatum Roxb. crop yield in Sikkim Himalaya, India

    Directory of Open Access Journals (Sweden)

    Kailash S. Gaira

    2016-03-01

    Full Text Available Large cardamom (Amomum subulatum Roxb., a perennial cash crop, cultivated under an agroforestry system in the eastern Himalaya of India, is well recognized as a pollination-dependent crop. Observations on pollinator abundance in Mamlay watershed of Sikkim Himalaya were collected during the blooming season to evaluate the pollinator abundance across sites and time frames, and impact of pollinator abundance on crop yield from 2010 to 2012. The results revealed that the bumblebees and honeybees are most frequent visitors of large cardamom flowers. The abundance of honeybees, however, varied between sites for the years 2010–2012, while that of bumblebees varied for the years 2011 and 2012. The abundance of honeybees resulted in a variation within time frames for 2010 and 2011, while that of bumblebees varied for 2010 and 2012 (p<0.01. The density of pollinators correlated positively with the number of flowers of the target crop. The impact of pollinator abundance revealed that the increasing bumblebee visitation resulted in a higher yield of the crop (i.e. 17–41 g/plant and the increasing abundance of all bees (21–41 g/plant was significant (p<0.03. Therefore, the study concluded that the large cardamom yield is sensitive to pollinator abundance and there is a need for adopting the best pollinator conservation and management practices toward sustaining the yield of large cardamom.

  7. Effect of crop (wheat) height and crop covered soil moisture on microwave scattering for remote sensing

    OpenAIRE

    Singh, Dharmendra; Yamaguchi, Yoshio; Yamada, Hiroyoshi; Singh, K.P.; Saran, S.K.

    2000-01-01

    An outdoor observation has been carried out for response of crop (wheat) height and crop covered soil moisture on microwave by an X- band scatterometer. Penetration of microwave into crop depends upon crop covered soil moisture, moisture content in crop, density of the crop, crop height and frequency of incident wave. When crop is green (wet) and lust i.e. the moisture content in the crop is height, the penetration depth is low. But, when crop is dry (i.e. fruit filling stage), the moistu...

  8. Control of floral transition in the bioenergy crop switchgrass.

    Science.gov (United States)

    Niu, Lifang; Fu, Chunxiang; Lin, Hao; Wolabu, Tezera W; Wu, Yanqi; Wang, Zeng-Yu; Tadege, Million

    2016-10-01

    Switchgrass (Panicum virgatum L.), a perennial warm season bunchgrass native to North America, has been a target in the U.S. as a renewable bioenergy crop because of its ability to produce moderate to high biomass yield on marginal soils. Delaying flowering can increase vegetative biomass production by allowing prolonged growth before switching to the reproductive phase. Despite the identification of flowering time as a biomass trait in switchgrass, the molecular regulatory factors involved in controlling floral transition are poorly understood. Here we identified PvFT1, PvAPL1-3 and PvSL1, 2 as key flowering regulators required from floral transition initiation to development of floral organs. PvFT1 expression in leaves is developmentally regulated peaking at the time of floral transition, and diurnally regulated with peak at approximately 2 h into the dark period. Ectopic expression of PvFT1 in Arabidopsis, Brachypodium and switchgrass led to extremely early flowering, and activation of FT downstream target genes, confirming that it is a strong activator of flowering in switchgrass. Ectopic expression of PvAPL1-3 and PvSL1, 2 in Arabidopsis also activated early flowering with distinct floral organ phenotypes. Our results suggest that switchgrass has conserved flowering pathway regulators similar to Arabidopsis and rice.

  9. An Integrated Lysimeter and Satellite Imagery Approach for Estimating Crop Evapotranspiration

    Science.gov (United States)

    Goorahoo, D.; Cassel-Sharma, F.; Johnson, L.; Melton, F. S.

    2014-12-01

    Accurate estimation of crop water requirement (CWR) is essential for the implementation efficient irrigation schedules in an effort to optimize water use efficiency. This is particularly important in the central San Joaquin Valley (SJV), California, USA, where severe droughts have accentuated the need to conserve water and improve on-farm water management. In the current study, we adopt an integrated approach for estimation of crop evapotranspiration (ETc) involving the use of weighing lysimeters and satellite imagery. In the first phase of the study with the crop lysimeter, conducted on a clay loam soil with processing tomatoes grown under sub-surface drip irrigation, observations of crop ground cover were conducted weekly and evapotranspiration (ET) data were collected daily to derive relationships between crop coefficients and fractional cover. Data collected during the first year of the study, indicted that the crop coefficients (Kc) obtained at peak season were relatively higher than those generally reported for tomatoes commonly grown in the central SJV. Overall, there was a good correlation between fractional cover and crop coefficients (r2 = 0.91), with the average peak ET and Kc values ranging from 6 to 7 mm per day and from 0.8 to 0.9, respectively. Data obtained from satellite imagery, representing relatively larger spatial measurements than the lysimeters, are being compared with the surface observations from the lysimeters and will also be discussed in our presentation.

  10. California Indian Food and Culture.

    Science.gov (United States)

    2001

    This learning kit begins with a glossary of terms to help students learn about California Indians and their food. The kit explains that California Indians were the first people to live in the area now known as California, and that these tribes differed in the languages they spoke, the regions they lived in, and the foods that they ate. It explains…

  11. Crop rotation modelling - A European model intercomparison

    DEFF Research Database (Denmark)

    Kollas, Chris; Kersebaum, Kurt C; Nendel, Claas;

    2015-01-01

    Diversification of crop rotations is considered an option to increase the resilience of European crop production under climate change. So far, however, many crop simulation studies have focused on predicting single crops in separate one-year simulations. Here, we compared the capability of fifteen...... sound representation of crop rotations, further research is required to synthesise existing knowledge of the physiology of intermediate crops and of carry-over effects from the preceding to the following crop, and to implement/improve the modelling of processes that condition these effects....... crop growth simulation models to predict yields in crop rotations at five sites across Europe under minimal calibration. Crop rotations encompassed 301 seasons of ten crop types common to European agriculture and a diverse set of treatments (irrigation, fertilisation, CO2 concentration, soil types...

  12. Plant senescence and crop productivity

    DEFF Research Database (Denmark)

    Gregersen, Per L.; Culetic, Andrea; Boschian, Luca;

    2013-01-01

    Senescence is a developmental process which in annual crop plants overlaps with the reproductive phase. Senescence might reduce crop yield when it is induced prematurely under adverse environmental conditions. This review covers the role of senescence for the productivity of crop plants...... plants, the expression of the IPT gene under control of senescence-associated promoters has been the most successful. The promoters employed for senescence-regulated expression contain cis-elements for binding of WRKY transcription factors and factors controlled by abscisic acid. In most crops...... transformed with such constructs the stay-green character has led to increased biomass, but only in few cases to increased seed yield. A coincidence of drought stress resistance and stay-green trait is observed in many transgenic plants....

  13. Chlorophyll Degradation in Horticultural Crops

    OpenAIRE

    Kaewsuksaeng, Samak

    2011-01-01

    One of the symptoms of senescence in harvested horticultural crops is the loss of greenness that comes with the degradation of chlorophyll. With senescence, the chlorophyll-degrading enzyme activities such as chlorophyllase, Mg-dechelatase or Mg-dechelation activity, a new chlorophyll-degrading enzyme, pheophytinase, pheophorbidase and chlorophyll-degrading peroxidase, which are involved in chlorophyll degradation, affected greatly in stored horticultural crops. The chlorophyll derivatives, e...

  14. Irrigation treatments, water use efficiency and crop sustainability in cereal-forage rotations in Mediterranean environment

    Directory of Open Access Journals (Sweden)

    Pasquale Martiniello

    2012-10-01

    Full Text Available Agricultural systems based on crop rotation are beneficial to crop sustainability and productivity. Wheat-forage rotations combined with irrigation are the agronomic techniques best able to exploit Mediterranean environmental conditions. This paper describes a long-term field trial to ascertain the effect of combined irrigation and durum wheat-forage rotations on crop yield and soil chemical properties. The two forage crops: annual grass-clover winter binary mixture and perennial lucerne were carried out through 1991-2008 under rainfed and irrigated treatments. The experiments were used to highlight the effect of irrigation and wheat-forage crop rotations on water use efficiency (WUE and sustainability of organic matter (OM in topsoil. Irrigation increased the dry matter (DM of annual binary mixture and lucerne by 49.1% and 66.9%, respectively. Continuous wheat rotation reduced seed yield (SY, stability of production, and crude protein (CP characteristics of kernel and OM in topsoil. The yearly gain in wheat after forage crops was 0.04 t (ha yr-1 under rainfed and 0.07 t (ha yr-1 under irrigation treatments. The CP and soil OM of wheat forage crops rotations, compared with those of continuous wheat under rainfed and irrigated was a 0.8 and 0.5 % increase in CP and 5.1 and 4.4 in OM, respectively. The rotations of annual grass-clover winter binary mixture and lucerne meadow under both irrigated treatments increased the OM over continuous wheat (9.3 % and 8.5 in annual grass-clover winter binary mixture and 12.5 and 9.5 lucerne meadow under rainfed and irrigation, respectively. Irrigation reduced the impact of weather on crop growing, reducing water use efficiency (mean over rotations for DM production (15.5 in meadow and 17.5 in annual grass-clover winter binary mixture [L water (kg DM-1] and wheat SY. However, the agronomic benefits achieved by forage crops in topsoil are exhausted after three years of continuous wheat rotation.

  15. Crop physiology calibration in CLM

    Directory of Open Access Journals (Sweden)

    I. Bilionis

    2014-10-01

    Full Text Available Farming is using more terrestrial ground, as population increases and agriculture is increasingly used for non-nutritional purposes such as biofuel production. This agricultural expansion exerts an increasing impact on the terrestrial carbon cycle. In order to understand the impact of such processes, the Community Land Model (CLM has been augmented with a CLM-Crop extension that simulates the development of three crop types: maize, soybean, and spring wheat. The CLM-Crop model is a complex system that relies on a suite of parametric inputs that govern plant growth under a given atmospheric forcing and available resources. CLM-Crop development used measurements of gross primary productivity and net ecosystem exchange from AmeriFlux sites to choose parameter values that optimize crop productivity in the model. In this paper we calibrate these parameters for one crop type, soybean, in order to provide a faithful projection in terms of both plant development and net carbon exchange. Calibration is performed in a Bayesian framework by developing a scalable and adaptive scheme based on sequential Monte Carlo (SMC.

  16. California State Waters Map Series—Offshore of Monterey, California

    Science.gov (United States)

    Johnson, Samuel Y.; Dartnell, Peter; Hartwell, Stephen R.; Cochrane, Guy R.; Golden, Nadine E.; Watt, Janet T.; Davenport, Clifton W.; Kvitek, Rikk G.; Erdey, Mercedes D.; Krigsman, Lisa M.; Sliter, Ray W.; Maier, Katherine L.; Johnson, Samuel Y.; Cochran, Susan A.

    2016-08-18

    IntroductionIn 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath bathymetry data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow subsurface geology.The Offshore of Monterey map area in central California is located on the Pacific Coast, about 120 km south of San Francisco. Incorporated cities in the map area include Seaside, Monterey, Marina, Pacific Grove, Carmel-by-the-Sea, and Sand City. The local economy receives significant resources from tourism, as well as from the Federal Government. Tourist attractions include the Monterey Bay Aquarium, Cannery Row, Fisherman’s Wharf, and the many golf courses near Pebble Beach, and the area serves as a gateway to the spectacular scenery and outdoor activities along the Big Sur coast to the south. Federal facilities include the Army’s Defense Language Institute, the Naval Postgraduate School, and the Fleet Numerical Meteorology and Oceanography Center (operated by the Navy). In 1994, Fort Ord army base, located between Seaside and Marina, was closed; much of former army base land now makes up the Fort Ord National Monument, managed by the U.S. Bureau of Land Management as part of the National Landscape Conservation System. In addition, part of the old Fort Ord is now occupied by California State University, Monterey Bay.The offshore part of the map area lies entirely within the Monterey Bay National

  17. SOUTH WARNER WILDERNESS, CALIFORNIA.

    Science.gov (United States)

    Duffield, Wendell A.; Weldin, Robert E.

    1984-01-01

    A mineral appraisal utilized geologic, geochemical, and geophysical data and an examination of mining claims in the South Warner Wilderness, California. Results of this study indicate that little promise for the occurrence of mineral resources exists within the area. Small veins of optical quality calcite occur on the east side of the area but, are not considered a resource.

  18. Indians of California.

    Science.gov (United States)

    Bureau of Indian Affairs (Dept. of Interior), Washington, DC.

    A brief historical review of the American Indian in California from prehistoric to modern times indicates the hardships and economic disadvantages which the Indians have suffered in the acculturation process. Discussion of the treaties which were negotiated and the Federal legislation which was passed indicates an attempt on the part of modern day…

  19. Computerevolution in California.

    Science.gov (United States)

    Kobryn, Nancy M.

    The introduction of the microcomputer is producing complex changes in the cosmopolitan culture of Californians, including the way people live and learn at home, in school, and at the office. Recently, many bills have been proposed in California to introduce computer science and technology into the public education system; in addition, tax credits…

  20. Cutting Propagation of Two Perennial Species in While Pine Tree Substrates

    Science.gov (United States)

    Wood-based materials, such as processed whole pine trees (WPT), have been identified as possible substitutions or replacements for peat moss (P) and pine bark (PB) in container substrates. Although wood-based substrates can be successfully used for crop production, limited information exists for ste...

  1. Potential productivity of the Miscanthus energy crop in the Loess Plateau of China under climate change

    International Nuclear Information System (INIS)

    With a vast area of marginal land, the Loess Plateau of China is a promising region for large-scale production of second-generation energy crops. However, it remains unknown whether such production is sustainable in the long run, especially under climate change. Using a regional climate change model, PRECIS, we analyzed the impact of climate change on Miscanthus production in the Loess Plateau. Under three emission scenarios, A2, B2, and A1B, both the average yield and total area capable of supporting Miscanthus production would increase continuously in the future period (2011–2099). As a result, the total yield potential in the region would increase by about 20% in this future period from the baseline period (1961–1990). This was explained primarily by predicted increases in temperature and precipitation across the Loess Plateau, which improved the yield of the perennial C4 plants relying exclusively on rainfed production. The areas that are currently too dry or too cold to support Miscanthus production could be turned into energy crop fields, especially along the arid–semiarid transition zone. Thus the Loess Plateau would become increasingly desirable for growing second-generation energy crops in this century, which could in turn contribute to soil improvement and ecological restoration of the region. (letter)

  2. Alternatives to crop residues for soil amendment

    OpenAIRE

    Powell, J.M.; Unger, P.W.

    1997-01-01

    Metadata only record In semiarid agroecosystems, crop residues can provide important benefits of soil and water conservation, nutrient cycling, and improved subsequent crop yields. However, there are frequently multiple competing uses for residues, including animal forage, fuel, and construction material. This chapter discusses the various uses of crop residues and examines alternative soil amendments when crop residues cannot be left on the soil.

  3. Comparing the Net Ecosystem Exchange of Two Cropping Systems for Dairy Feed Production

    Science.gov (United States)

    Sulaiman, M. F.; Wagner-Riddle, C.; Brown, S. E.

    2015-12-01

    A three-year study was conducted from 2012 to 2014 to determine the net CO2 fluxes from corn and hay, the two main feed crops used in dairy production. The aim of this study is to better understand the net ecosystem exchange (NEE) in annual and perennial cropping systems used in dairy production to benefit greenhouse gas emission model developments and the life cycle analysis of dairy production. The study was conducted on two 4-ha plots where one plot was a 5-year old hayfield and the other plot was planted in a continuous cycle corn. All plots were continuously monitored using the flux-gradient method deployed with a tunable diode laser trace gas analyzer and sonic anemometers. All plots received dairy manure as fertilizer applied according to common practice. The cumulative NEE for the three years of the study was -873.15 g C m-2 for corn and -409.36 g C m-2 for hay. Differences in respiration between the two cropping systems was found to be the larger factor compared to differences in gross ecosystem production (GEP) that resulted in the contrasting cumulative NEE where cumulative respiration for the three years for hay was 3094.23 g C m-2 as opposed to 2078.11 g C m-2 for corn. Cumulative GEP for the three years was 3503.60 and 2951.31 g C m-2 for hay and corn respectively. Inter-annual and inter-crop variability of the NEE, GEP and respiration will be discussed in relation to biomass production, climatic conditions and crop physiological characteristics.

  4. Productivity and carbon dioxide exchange of leguminous crops: estimates from flux tower measurements

    Science.gov (United States)

    Gilmanov, Tagir G.; Baker, John M.; Bernacchi, Carl J.; Billesbach, David P.; Burba, George G.; Castro, Saulo; Chen, Jiquan; Eugster, Werner; Fischer, Marc L.; Gamon, John A.; Gebremedhin, Maheteme T.; Glenn, Aaron J.; Griffis, Timothy J.; Hatfield, Jerry L.; Heuer, Mark W.; Howard, Daniel M.; Leclerc, Monique Y.; Loescher, Henry W.; Marloie, Oliver; Meyers, Tilden P.; Olioso, Albert; Phillips, Rebecca L.; Prueger, John H.; Skinner, R. Howard; Suyker, Andrew E.; Tenuta, Mario; Wylie, Bruce K.

    2014-01-01

    Net CO2 exchange data of legume crops at 17 flux tower sites in North America and three sites in Europe representing 29 site-years of measurements were partitioned into gross photosynthesis and ecosystem respiration by using the nonrectangular hyperbolic light-response function method. The analyses produced net CO2 exchange data and new ecosystem-scale ecophysiological parameter estimates for legume crops determined at diurnal and weekly time steps. Dynamics and annual totals of gross photosynthesis, ecosystem respiration, and net ecosystem production were calculated by gap filling with multivariate nonlinear regression. Comparison with the data from grain crops obtained with the same method demonstrated that CO2 exchange rates and ecophysiological parameters of legumes were lower than those of maize (Zea mays L.) but higher than for wheat (Triticum aestivum L.) crops. Year-round annual legume crops demonstrated a broad range of net ecosystem production, from sinks of 760 g CO2 m–2 yr–1 to sources of –2100 g CO2 m–2 yr–1, with an average of –330 g CO2 m–2 yr–1, indicating overall moderate CO2–source activity related to a shorter period of photosynthetic uptake and metabolic costs of N2 fixation. Perennial legumes (alfalfa, Medicago sativa L.) were strong sinks for atmospheric CO2, with an average net ecosystem production of 980 (range 550–1200) g CO2 m–2 yr–1.

  5. Herbaceous crops and trees can provide bioenergy needs in humid Lower South, USA

    Energy Technology Data Exchange (ETDEWEB)

    Prine, G.M.; Rockwood, D.L. [University of Florida, Gainesville, FL (United States)

    1999-07-01

    The Humid Lower South (HLS) can be a leading producer of bioenergy. It has adequate land area, long warm growing season, high rainfall and a subtropical climate which allows production of a number of tropical perennial grasses, the tropical tree legume leucaena, and short rotation woody trees. The vegetatively propagated tall grasses, sugarcane and energy cane (Saccarhum sp.), elephantgrass (Pennisetum purpureum) and erianthus (Erianthus arundenaceum), all have high linear growth rates of 17 to 27 g m{sup -2} d{sup -1} for 140 to 196 days or longer. Dry matter yields of 20 to 60 Mg ha{sup -1} yr{sup -1} are possible depending on crop, location, season, soils, management and climate. The seed propagated switch grass (Panicum virgatum) offers sustainable dry biomass production of 15 to 22 Mg ha{sup -1} yr{sup -1}. Tall castor bean (Ricinus communis) has produced two-year-old dry stem yield of 65 Mg ha{sup -.} Leucaena (Leucaena sp.) has an annual or multiple season woody stem production with potential dry matter annual yields of 19 to 31 Mg ha{sup -1}. Besides these herbaceous crops the vast natural forests can be supplemented by short rotation woody crops having potential yields of 15-35 dry Mg ha{sup -1} yr{sup -l}. The northern portion of HLS can grow short rotation cottonwood (Populus deltoides) and slash pine (Pinus elliottii) on many soils. Eucalyptus species can be grown in peninsular Florida. Culture of the bioenergy crops is enhanced by application of sewage sludge and waste waters. Industries can take advantage of various mixtures of these available high-biomass-yielding crops for energy use. (author)

  6. Measuring IPM Impacts in California and Arizona

    Science.gov (United States)

    Farrar, J. J.; Baur, M. E.; Elliott, S. F.

    2016-01-01

    Integrated pest management (IPM) is a method of reducing economic, human health, and environmental risks from pests and pest management strategies. There are questions about the long-term success of IPM programs in relation to continued use of pesticides in agriculture. Total pounds of pesticides applied is a mis-measure of the impact of IPM in agriculture. A more complete measurement of the long-term impact of IPM includes consideration of changes in agricultural production practices and productivity, toxicity of the pesticides used, risks from human exposure to pesticides, and environmental sampling for pesticides in air and water resources. In recent decades, agricultural IPM programs have evolved to address invasive pests, shifts in endemic pest pressures, reductions in pest damage tolerance in markets, and increases in crop yields. Additionally, pesticide use data from Arizona and California revealed reduced use of pesticides in some toxicity categories but increased use of pesticides in a couple of categories. Data from federal and California programs that monitored pesticide residue on food have documented low pesticide risk to consumers. Environmental monitoring programs documented decreased pesticide levels in surface water resources in agricultural watersheds in the western United States and low levels of pesticides in air resources in agricultural areas in California. The focus of IPM assessment should be on reducing economic, human health, and environmental risks, not on pounds of pesticides applied. More broadly, IPM programs have evolved to address changes in pests and agricultural production systems while continuing to reduce human health and environmental risk from pesticides. PMID:27812396

  7. Growth and metal accumulation of an Alyssum murale nickel hyperaccumulator ecotype co-cropped with Alyssum montanum or perennial ryegrass in serpentine soil

    Science.gov (United States)

    More than 400 plant species naturally accumulate high levels of metals such as Cd, Cu, Co, Mn, Ni, and Zn. The genus Alyssum (Brassicaceae) contains the greatest number of reported Ni hyperaccumulators (50), many of which can achieve 3 wt% Ni in dry leaves. Some Alyssum hyperaccumulators are viabl...

  8. Management current land use of perennial industrial crops by NDVI index: A case study in Chu Se District, Gia Lai Province, Vietnam

    OpenAIRE

    Nguyen, Hoang Khanh Linh; Nguyen, Bich Ngoc

    2015-01-01

    Remote sensing and Geographic Information System (GIS) - an effective tool for managing naturalresources, is quite common application in establishing thematic maps. However, the application of this modern technology in natural resource management has not yet been popular in Vietnam, particularly mapping the land use/cover. Currently, land use/cover map is constructed as traditional methods and gets limitations of management counting due to time-consuming for mapping andsynthesis the status of...

  9. The role of drainage ditches in greenhouse gas emissions and surface leaching losses from a cutaway peatland cultivated with a perennial bioenergy crop

    Energy Technology Data Exchange (ETDEWEB)

    Hyvonen, N.P.; Huttunen, J.T.; Shurpali, N.J.; Lind, S.E.; Marushchak, M.E.; Martikainen, P.J. [University of Eastern Finland, Kuopio (Finland). Dept. of Environmental Science], E-mail: niina.hyvonen@uef.fi; Heitto, L. [Environmental Research of Savo-Karjala Ltd, Kuopio (Finland)

    2013-06-01

    We studied greenhouse gas (GHG) emissions from drainage ditches and leaching losses in a boreal cutaway peatland cultivated with reed canary grass (Phalaris arundinacea) for bioenergy. The objectives of the study were to assess to what extent GHG emissions from drainage ditches and leaching of carbon and nutrients via surface drainage contribute to the total losses of carbon and nitrogen from the site. The emissions of CH{sub 4}, N{sub 2}O and CO{sub 2} were measured with static chamber methods for three years and leaching losses for seven years. On average, the drainage ditches (covering 6% of the study site area) released 10% of the total CH{sub 4} emission (0.33 g m{sup -2} a{sup -1}), and 1% and 5% of the total N{sub 2}O and CO{sub 2} emissions, respectively. Leaching of total nitrogen and phosphorous were 0.31 and 0.03 g m{sup -2} a{sup -1}, respectively. Leaching values were lower than those reported for agricultural catchments in general. (orig.)

  10. Escape to Ferality: The Endoferal Origin of Weedy Rice from Crop Rice through De-Domestication

    Science.gov (United States)

    Gettler, Kyle A.; Burgos, Nilda R.; Fischer, Albert J.

    2016-01-01

    Domestication is the hallmark of evolution and civilization and harnesses biodiversity through selection for specific traits. In regions where domesticated lines are grown near wild relatives, congeneric sources of aggressive weedy genotypes cause major economic losses. Thus, the origins of weedy genotypes where no congeneric species occur raise questions regarding management effectiveness and evolutionary mechanisms responsible for weedy population success. Since eradication in the 1970s, California growers avoided weedy rice through continuous flood culture and zero-tolerance guidelines, preventing the import, presence, and movement of weedy seeds. In 2003, after decades of no reported presence in California, a weedy rice population was confirmed in dry-seeded fields. Our objectives were to identify the origins and establishment of this population and pinpoint possible phenotypes involved. We show that California weedy rice is derived from a different genetic source among a broad range of AA genome Oryzas and is most recently diverged from O. sativa temperate japonica cultivated in California. In contrast, other weedy rice ecotypes in North America (Southern US) originate from weedy genotypes from China near wild Oryza, and are derived through existing crop-wild relative crosses. Analyses of morphological data show that California weedy rice subgroups have phenotypes like medium-grain or gourmet cultivars, but have colored pericarp, seed shattering, and awns like wild relatives, suggesting that reversion to non-domestic or wild-like traits can occur following domestication, despite apparent fixation of domestication alleles. Additionally, these results indicate that preventive methods focused on incoming weed sources through contamination may miss burgeoning weedy genotypes that rapidly adapt, establish, and proliferate. Investigating the common and unique evolutionary mechanisms underlying global weed origins and subsequent interactions with crop relatives sheds

  11. Development and Deployment of a Short Rotation Woody Crops Harvesting System Based on a Case New Holland Forage Harvester and SRC Woody Crop Header

    Energy Technology Data Exchange (ETDEWEB)

    Eisenbies, Mark [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States); Volk, Timothy [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States); Abrahamson, Lawrence [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States); Shuren, Richard [GreenWood Resources, Inc., Portland, OR (United States); Stanton, Brian [GreenWood Resources, Inc., Portland, OR (United States); Posselius, John [Case New Holland, New Holland, PA (United States); McArdle, Matt [Mesa Reduction Engineering and Processing, Inc., Auburn, NY (United States); Karapetyan, Samvel [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States); Patel, Aayushi [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States); Shi, Shun [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States); Zerpa, Jose [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States)

    2014-10-03

    Biomass for biofuels, bioproducts and bioenergy can be sourced from forests, agricultural crops, various residue streams, and dedicated woody or herbaceous crops. Short rotation woody crops (SRWC), like willow and hybrid poplar, are perennial cropping systems that produce a number of environmental and economic development benefits in addition to being a renewable source of biomass that can be produced on marginal land. Both hybrid poplar and willow have several characteristics that make them an ideal feedstock for biofuels, bioproducts, and bioenergy; these include high yields that can be obtained in three to four years, ease of cultivar propagation from dormant cuttings, a broad underutilized genetic base, ease of breeding, ability to resprout after multiple harvests, and feedstock composition similar to other sources of woody biomass. Despite the range of benefits associated with SRWC systems, their deployment has been restricted by high costs, low market acceptance associated with inconsistent chip quality (see below for further explanation), and misperceptions about other feedstock characteristics (see below for further explanation). Harvesting of SRWC is the largest single cost factor (~1/3 of the final delivered cost) in the feedstock supply system. Harvesting is also the second largest input of primary fossil energy in the system after commercial N fertilizer, accounting for about one third of the input. Therefore, improving the efficiency of the harvesting system has the potential to reduce both cost and environmental impact. At the start of this project, we projected that improving the overall efficiency of the harvesting system by 25% would reduce the delivered cost of SRWC by approximately $0.50/MMBtu (or about $7.50/dry ton). This goal was exceeded over the duration of this project, as noted below.

  12. Development of water facilities in the Santa Ana River Basin, California, 1810-1968: a compilation of historical notes derived from many sources describing ditch and canal companies, diversions, and water rights

    Science.gov (United States)

    Scott, M.B.

    1977-01-01

    This report traces by text, maps, and photographs, the development of the water supply in the Santa Ana River basin from its beginning in 1810 or 1811 to 1968. The value of the report lies in the fact that interpretation of the hydrologic systems in the basin requires knowledge of the concurrent state of development of the water supply, because that development has progressively altered the local regimen of both surface water and ground water. Most of the information for the earlier years was extracted and condensed from an investigation made by W. H. Hall, California State Engineer during the years 1878-87. Hall's study described irrigation development in southern California from its beginning through 1888. Information for the years following 1888 was obtained from the archives of the numerous water companies and water agencies in the Santa Ana River basin and from the various depositories of courthouse, county, and municipal records. The history of water-resources development in the Santa Ana River basin begins with the introduction of irrigation in the area by the Spanish, who settled in southern California in the latter part, of the 18th century. The first irrigation diversion from the Santa Ana River was made in 1810 or 1811 by Jose Antonio Yorba and Juan Pablo Peralta. Irrigation remained a localized practice during the Mexican-Californian, or rancho, period following the separation of Mexico from Spain in 1821. Rancho grantees principally raised cattle, horses, and sheep and irrigated only small· plots of feed grain for their livestock and fruit crops for household use. The breakup of the ranchos through sales to Americans, who were migrating to California in ever-increasing numbers following the acquisition of California by the United States in 1848, marked the beginning of a rapid increase in water use and the beginning of widespread irrigation. Many water companies and water agencies were organized to divert the surface flow of the Santa Ana River and

  13. Gibberellin Promotes Shoot Branching in the Perennial Woody Plant Jatropha curcas.

    Science.gov (United States)

    Ni, Jun; Gao, Congcong; Chen, Mao-Sheng; Pan, Bang-Zhen; Ye, Kaiqin; Xu, Zeng-Fu

    2015-08-01

    Strigolactone (SL), auxin and cytokinin (CK) interact to regulate shoot branching. CK has long been considered to be the only key phytohormone to promote lateral bud outgrowth. Here we report that gibberellin also acts as a positive regulator in the control of shoot branching in the woody plant Jatropha curcas. We show that gibberellin and CK synergistically promote lateral bud outgrowth, and that both hormones influence the expression of putative branching regulators, J. curcas BRANCHED1 and BRANCHED2, which are key transcription factors maintaining bud dormancy. Moreover, treatment with paclobutrazol, an inhibitor of de novo gibberellin biosynthesis, significantly reduced the promotion of bud outgrowth by CK, suggesting that gibberellin is required for CK-mediated axillary bud outgrowth. In addition, SL, a plant hormone involved in the repression of shoot branching, acted antagonistically to both gibberellin and CK in the control of lateral bud outgrowth. Consistent with this, the expression of JcMAX2, a J. curcas homolog of Arabidopsis MORE AXILLARY GROWTH 2 encoding an F-box protein in the SL signaling pathway, was repressed by gibberellin and CK treatment. We also provide physiological evidence that gibberellin also induces shoot branching in many other trees, such as papaya, indicating that a more complicated regulatory network occurs in the control of shoot branching in some perennial woody plants. PMID:26076970

  14. Differential regulation of two sucrose transporters by defoliation and light conditions in perennial ryegrass.

    Science.gov (United States)

    Furet, Pierre-Maxime; Berthier, Alexandre; Decau, Marie-Laure; Morvan-Bertrand, Annette; Prud'homme, Marie-Pascale; Noiraud-Romy, Nathalie; Meuriot, Frédéric

    2012-12-01

    Sucrose transport between source and sink tissues is supposed to be a key-step for an efficient regrowth of perennial rye-grass after defoliation and might be altered by light conditions. We assessed the effect of different light regimes (high vs low light applied before or after defoliation) on growth, fructans and sucrose mobilization, as well as on sucrose transporter expression during 14 days of regrowth. Our results reported that defoliation led to a mobilization of C reserves (first sucrose and then fructans), which was parallel to an induction of LpSUT1 sucrose transporter expression in source and sink tissues (i.e. leaf sheaths and elongating leaf bases, respectively) irrespective to light conditions. Light regime (high or low light) had little effects on regrowth and on C reserves mobilization during the first 48 h of regrowth after defoliation. Thereafter, low light conditions, delaying the recovery of photosynthetic capacities, had a negative effect on C reserves re-accumulation (especially sucrose). Surprisingly, high light did not enhance sucrose transporter expression. Indeed, while light conditions had no effect on LpSUT1 expression, LpSUT2 transcripts levels were enhanced for low light grown plants. These results indicate that two sucrose transporter currently identified in Lolium perenne L. are differentially regulated by light and sucrose.

  15. Epigenetic differentiation persists after male gametogenesis in natural populations of the perennial herb Helleborus foetidus (Ranunculaceae.

    Directory of Open Access Journals (Sweden)

    Carlos M Herrera

    Full Text Available Despite the importance of assessing the stability of epigenetic variation in non-model organisms living in real-world scenarios, no studies have been conducted on the transgenerational persistence of epigenetic structure in wild plant populations. This gap in knowledge is hindering progress in the interpretation of natural epigenetic variation. By applying the methylation-sensitive amplified fragment length polymorphism (MSAP technique to paired plant-pollen (i.e., sporophyte-male gametophyte DNA samples, and then comparing methylation patterns and epigenetic population differentiation in sporophytes and their descendant gametophytes, we investigated transgenerational constancy of epigenetic structure in three populations of the perennial herb Helleborus foetidus (Ranunculaceae. Single-locus and multilocus analyses revealed extensive epigenetic differentiation between sporophyte populations. Locus-by-locus comparisons of methylation status in individual sporophytes and descendant gametophytes showed that ~75% of epigenetic markers persisted unchanged through gametogenesis. In spite of some epigenetic reorganization taking place during gametogenesis, multilocus epigenetic differentiation between sporophyte populations was preserved in the subsequent gametophyte stage. In addition to illustrating the efficacy of applying the MSAP technique to paired plant-pollen DNA samples to investigate epigenetic gametic inheritance in wild plants, this paper suggests that epigenetic differentiation between adult plant populations of H. foetidus is likely to persist across generations.

  16. Transcriptome resources for the perennial sunflower Helianthus maximiliani obtained from ecologically divergent populations.

    Science.gov (United States)

    Kawakami, Takeshi; Darby, Brian J; Ungerer, Mark C

    2014-07-01

    Next-generation sequencing (NGS) technologies provide a rapid means to generate genomic resources for species exhibiting interesting ecological and evolutionary variation but for which such resources are scant or nonexistent. In the current report, we utilize 454 pyrosequencing to obtain transcriptome information for multiple individuals and tissue types from geographically disparate and ecologically differentiated populations of the perennial sunflower species Helianthus maximiliani. A total of 850 275 raw reads were obtained averaging 355 bp in length. Reads were assembled, postprocessing, into 16 681 unique contigs with an N50 of 898 bp and a total length of 13.6 Mb. A majority (67%) of these contigs were annotated based on comparison with the Arabidopsis thaliana genome (TAIR10). Contigs were identified that exhibit high similarity to genes associated with natural variation in flowering time and freezing tolerance in other plant species and will facilitate future studies aimed at elucidating the molecular basis of clinal life history variation and adaptive differentiation in H. maximiliani. Large numbers of gene-associated simple sequence repeats (SSRs) and single-nucleotide polymorphisms (SNPs) also were identified that can be deployed in mapping and population genomic analyses. PMID:24438509

  17. Differential Essential Oil Composition and Morphology between Perennial Satureja species Growing in Spain

    Directory of Open Access Journals (Sweden)

    David García-Rellán

    2015-06-01

    Full Text Available Chemical composition of the essential oils obtained by hydrodistillation from the aerial parts of thirty six samples of perennial Spanish savouries (Satureja montana L., Satureja innota (Pau G. López, Satureja cuneifolia Ten. and Satureja intricata Lange, was investigated by GC and GC-MS. A total of 72 compounds accounting between 98.25-99.55% of the total oil were identified. High content of carvacrol (59.72±1.50% followed by g -terpinene (17.40±1.11% were found in S.montana essential oils. S. cuneifolia yielded an oil rich in camphor (45.04±1.67% and camphene (12.42±1.71% whereas S. innota produces an essential oil with linalool (23.94±7.58% or geraniol (8.62±3.45% according to the locality of collection and S. intricata showed chemical polymorphism with camphor (16.02±1.75%, as the main compound followed with populations with myrcene (8.46±1.46% and populations with g -terpinene (8.22±1.33%. Although the morphological affinity between S. innota, S.cuneifolia and S. intricata could lead to consider the subspecies level, the phytochemical discriminant analysis support the taxonomic classification of Flora Iberica which ranks these taxa into species.

  18. Effect of Inhalation of Aromatherapy Oil on Patients with Perennial Allergic Rhinitis: A Randomized Controlled Trial.

    Science.gov (United States)

    Choi, Seo Yeon; Park, Kyungsook

    2016-01-01

    This study aimed to investigate the effects of aromatherapy oil inhalation on symptoms, quality of life, sleep quality, and fatigue level among adults with perennial allergic rhinitis (PAR). Fifty-four men and women aged between 20 and 60 were randomized to inhale aromatherapy oil containing essential oil from sandalwood, geranium, and Ravensara or almond oil (the placebo) for 5 minutes twice daily for 7 days. PAR symptoms determined by Total Nasal Symptom Score (TNSS), the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ), sleep quality by Verran Synder-Halpern (VSH) scale, and fatigue level by Chalder Fatigue Scale (CFS) were assessed before and after intervention period. Compared with the placebo, the experimental group showed significant improvement in TNSS, especially in nasal obstruction. The aromatherapy group also showed significantly higher improvements in total score of RQLQ and CFS. These findings indicate that inhalation of certain aromatherapy oil helps relieve PAR symptoms, improve rhinitis-specific quality of life, and reduce fatigue in patients with PAR. In conclusion, inhalation of aromatherapy essential oil may have potential as an effective intervention to alleviate PAR. PMID:27034695

  19. Population Dynamics and Life History of Euphorbia rosescens, a Perennial Herb Endemic to Florida Scrub

    Science.gov (United States)

    2016-01-01

    Euphorbia rosescens is a recently described plant that is narrowly endemic to the Lake Wales Ridge. Little is known of the ecology or life history of this diminutive, deeply rooted polygamodioecious perennial. We studied 13 subpopulations of this species from 2004–2012 from five habitats, sampling monthly during its growing season. Subpopulations were stable year-to-year with annual survivals > 90%, but with considerable within-year dynamics, peaking in density in April and dying back in the fall and winter. Stem densities did not vary among subpopulations, habitats, or by subpopulation gender. Annual plant dormancy was common and decreased subsequent survival. Belowground biomass averaged almost 50 times higher than aboveground biomass. Subpopulations either consisted of entirely female individuals or a mixture of male and functionally andromonoecious individuals and these subpopulation genders remained stable across years. Overall, flowering has been dominated by female plants. Plants produced modest numbers of inflorescences (cyathia), and fruit production was very low. Although most plants survived fire by resprouting, fire decreased survival and had a short-term positive effect on floral production. Lack of fecundity and recruitment are concerns for this state-endangered species, but more information is needed on its breeding system and clonality to make specific management recommendations. PMID:27454519

  20. Effect of Inhalation of Aromatherapy Oil on Patients with Perennial Allergic Rhinitis: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Seo Yeon Choi

    2016-01-01

    Full Text Available This study aimed to investigate the effects of aromatherapy oil inhalation on symptoms, quality of life, sleep quality, and fatigue level among adults with perennial allergic rhinitis (PAR. Fifty-four men and women aged between 20 and 60 were randomized to inhale aromatherapy oil containing essential oil from sandalwood, geranium, and Ravensara or almond oil (the placebo for 5 minutes twice daily for 7 days. PAR symptoms determined by Total Nasal Symptom Score (TNSS, the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ, sleep quality by Verran Synder-Halpern (VSH scale, and fatigue level by Chalder Fatigue Scale (CFS were assessed before and after intervention period. Compared with the placebo, the experimental group showed significant improvement in TNSS, especially in nasal obstruction. The aromatherapy group also showed significantly higher improvements in total score of RQLQ and CFS. These findings indicate that inhalation of certain aromatherapy oil helps relieve PAR symptoms, improve rhinitis-specific quality of life, and reduce fatigue in patients with PAR. In conclusion, inhalation of aromatherapy essential oil may have potential as an effective intervention to alleviate PAR.

  1. Body size and clonality consequences for sexual reproduction in a perennial herb of Brazilian rupestrian grasslands.

    Science.gov (United States)

    Demetrio, G R; Coelho, F F; Barbosa, M E A

    2014-08-01

    Body size is one of the most important factors regarding herbaceous perennial plants life-histories, and several fitness components of these organisms are related to size. Clonal plants show distinct kinds of reproduction and can develop offspring by sexual or asexual ways. We aimed to understand how body size affects Comanthera nivea (Eriocaulaceae) sexual reproduction and to verify how clonal growth is related to flower head production in this species. We sampled 600 rosettes in rupestrian grasslands and performed linear regression analysis between body size and number of produced flower heads. We also compared the flower head production between isolated rosettes and rosettes within clones. Our results showed that body size was significantly related, but explained only a small part of flower head production. The flower head production was higher in rosettes within clones than in isolated ones. The clones presented a rosette or a small group of rosettes that concentrated the sexual reproduction. Clonality was positively associated with sexual reproduction. Clonality can represent an important way of allowing the persistence of plants by sexual reproduction in markedly seasonal stressful environments. The cases of clonality enhancing the sexual reproduction must be considered and put in focus on reproductive biology research.

  2. Temporal dynamics of the metabolically active rumen bacteria colonizing fresh perennial ryegrass.

    Science.gov (United States)

    Huws, Sharon A; Edwards, Joan E; Creevey, Christopher J; Rees Stevens, Pauline; Lin, Wanchang; Girdwood, Susan E; Pachebat, Justin A; Kingston-Smith, Alison H

    2016-01-01

    This study investigated successional colonization of fresh perennial ryegrass (PRG) by the rumen microbiota over time. Fresh PRG was incubated in sacco in the rumens of three Holstein × Friesian cows over a period of 8 h, with samples recovered at various times. The diversity of attached bacteria was assessed using 454 pyrosequencing of 16S rRNA (cDNA). Results showed that plant epiphytic communities either decreased to low relative abundances or disappeared following rumen incubation, and that temporal colonization of the PRG by the rumen bacteria was biphasic with primary (1 and 2 h) and secondary (4-8 h) events evident with the transition period being with 2-4 h. A decrease in sequence reads pertaining to Succinivibrio spp. and increases in Pseudobutyrivibrio, Roseburia and Ruminococcus spp. (the latter all order Clostridiales) were evident during secondary colonization. Irrespective of temporal changes, the continually high abundances of Butyrivibrio, Fibrobacter, Olsenella and Prevotella suggest that they play a major role in the degradation of the plant. It is clear that a temporal understanding of the functional roles of these microbiota within the rumen is now required to unravel the role of these bacteria in the ruminal degradation of fresh PRG.

  3. Water Supply Changes N and P Conservation in a Perennial Grass Leymus chinensis

    Institute of Scientific and Technical Information of China (English)

    Ju-Ying Huang; Hai-Long Yu; Ling-Hao Li; Zhi-You Yuan; Samuel Bartels

    2009-01-01

    Changes in precipitation can influence soil water and nutrient availability, and thus affect plant nutrient conservation strategies. Better understanding of how nutrient conservation changes with variations in water availability is crucial for predicting the potential influence of global climate change on plant nutrient-use strategy. Here, green-leaf nitrogen (N) and phosphorus (P) concentrations, N- and P-resorption proficiency (the terminal N and P concentration in senescent leaves,NRP and PRP, respectively), and N- and P-resorption efficiency (the proportional N and P withdrawn from senescent leaves prior to abscission, NRE and PRE, respectively) of Leymus chinensis (Trin.) Tzvel., a typical perennial grass species in northern China, were examined along a water supply gradient to explore how plant nutrient conservation responds to water change. Increasing water supply at low levels ( 9000 mL/year). These results indicated that changes in water availability at low levels could affect leaf-level nutrient characteristics, especially for the species in semiarid ecosystems. Therefore, global changes in precipitation may pose effects on plant nutrient economy, and thus on nutrient cycling in the plant-soil systems.

  4. Winter survival and deacclimation of perennials under warming climate: physiological perspectives.

    Science.gov (United States)

    Pagter, Majken; Arora, Rajeev

    2013-01-01

    Appropriate timing and rate of cold deacclimation and the ability to reacclimate are important components of winter survival of perennials in temperate and boreal zones. In association with the progressive increase in atmospheric CO₂, temperate and boreal winters are becoming progressively milder, and temperature patterns are becoming irregular with increasing risk of unseasonable warm spells during the colder periods of plants' annual cycle. Because deacclimation is mainly driven by temperature, these changes pose a risk for untimely/premature deacclimation, thereby rendering plant tissue vulnerable to freeze-injury by a subsequent frost. Research also indicates that elevated CO₂ may directly impact deacclimation. Hence, understanding the underlying cellular mechanisms of how deacclimation and reacclimation capacity are affected by changes in environmental conditions is important to ensure winter survival and the sustainability of plant sources under changing climate. Relative to cold acclimation, deacclimation is a little studied process, but the limited evidence points to specific changes occurring in the transcriptome and proteome during deacclimation. Loss of freezing tolerance is additionally associated with substantial changes in cell/tissue-water relations and carbohydrate metabolism; the latter also impacted by temperature-driven, altered respiratory metabolism. This review summarizes recent progress in understanding the physiological mechanisms of deacclimation and how they may be impacted by climate change. PMID:22583023

  5. Organic matter quality in a soil cultivated with perennial herbaceous legumes

    Directory of Open Access Journals (Sweden)

    Canellas Luciano Pasqualoto

    2004-01-01

    Full Text Available Using herbaceous legumes in agricultural systems yields great quantities of plant residues, allowing changes in soil organic matter quality and content over the years. This study was conducted on an Ultisol, at Seropédica, RJ, Brazil, to evaluate the effects of different perennial herbaceous legumes on soil organic matter quality. A factorial scheme with three replications was used to evaluate the species: forage groundnut cv. BR-14951 (Arachis pintoi, tropical kudzu (Pueraria phaseoloides, and siratro (Macroptilium atropurpureum. After the first cut, each plot was divided into two subplots; plants were cut and left on the soil surface or cut and removed. Soil samples of a closed area covered by spontaneous vegetation (mainly C3 plants or by Panicum maximum were also analysed. Samples were collected from two layers (0-5 and 5-10 cm, processed for the fractionation of organic matter and the evaluation of structural characteristics of humic acids (HA. Evaluated legumes did not change total organic carbon contents, but promoted HA accumulation in the superficial soil layer. Humic acids may be used as indicators of the management effects on soil organic fractions, because there was significant incorporation of carbon and nitrogen derived from the legume residues, even for the short experimentation time (28 months. Residue management did not modify quantitative aspects of the distribution of the humified organic matter, but promoted, however, a higher condensation degree of humic acids evaluated by the elementary composition, IR and fluorescence spectroscopy.

  6. The evolution of optimal resource allocation and mating systems in hermaphroditic perennial plants

    Science.gov (United States)

    Wang, Ya-Qiang; Li, Yao-Tang; Wang, Rui-Wu

    2016-01-01

    By incorporating the effects of inbreeding depression (ID) on both juveniles and adults survivorship, we developed a new theoretical model for hermaphroditic perennial plants. Our model showed that the effect of the selfing rate on the evolutionarily stable strategy (ESS) reproductive allocation depends on three parameters: (1) the self-fertilized juvenile relative survivorship (SFJRS), (2) the self-fertilized adult relative survivorship (SFARS) and (3) the growth rate of self-fertilized adult, where the SFJRS is the survivorship of self-fertilized juveniles divided by the survivorship of outcrossed juveniles, and likewise for the SFARS. However, the ESS sex allocation decreases as the selfing rate increases. This relationship seems independent of the SFJRS, the SFARS, and the growth rate of self-fertilized adults. Additionally, our model showed that the complete outcrossing is an ESS when the fraction of juvenile inbreeding depression (FJID) is less than 1/2 − τ, where τ is the self-fertilized adults mortality rate caused by ID. In contrast, the complete selfing also acts as an ESS when the FJID is greater than 1/2 − τ. These results could explain the diversity of mating strategies and related resource allocations for plants. PMID:27681446

  7. Seasonal variations of cadmium and zinc in Arrhenatherum elatius, a perennial grass species from highly contaminated soils

    International Nuclear Information System (INIS)

    There is interest in studying bioaccumulation in plants because they form the base of the food chain as well as their potential use in phytoextraction. From this viewpoint, our study deals with the seasonal variation, from January to July, of Cd and Zn bioaccumulation in three metallicolous populations of Arrhenatherum elatius, a perennial grass with a high biomass production. In heavily polluted soils, while Zn bioaccumulation is weak, A. elatius accumulates more Cd than reported gramineous plants, with concentration of up to 100 μg g-1. Our results also showed seasonal variations of bioaccumulation, underlying the necessity for in situ studies to specify the date of sampling and also the phenology of the collected plant sample. In our experimental conditions, accumulation is lower in June, leading us to the hypothesis of restriction in heavy metals translocation from roots to aerial parts during seed production. - Cd and Zn bioaccumulation varies seasonally in a perennial grass

  8. Seasonal variations of cadmium and zinc in Arrhenatherum elatius, a perennial grass species from highly contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Deram, Annabelle [Institut Lillois d' Ingenierie de la Sante, Universite Droit et Sante de Lille, EA 2690, 42 rue Ambroise Pare, 59120 Loos (France)]. E-mail: aderam@ilis.univ-lille2.fr; Denayer, Franck-Olivier [Institut Lillois d' Ingenierie de la Sante, Universite Droit et Sante de Lille, EA 2690, 42 rue Ambroise Pare, 59120 Loos (France); Petit, Daniel [Laboratoire de Genetique et Evolution des Populations Vegetales, UPRESA-CNRS 8016, Bat SN2, Universite des Sciences et Techniques de Lille, 59655 Villeneuve d' Ascq, F59655 France (France); Van Haluwyn, Chantal [Faculte des Sciences Pharmaceutiques et Biologiques, Departement de Botanique, Universite Droit et Sante de Lille, EA 2690, B.P. 83, 59006 Lille Cedex (France)

    2006-03-15

    There is interest in studying bioaccumulation in plants because they form the base of the food chain as well as their potential use in phytoextraction. From this viewpoint, our study deals with the seasonal variation, from January to July, of Cd and Zn bioaccumulation in three metallicolous populations of Arrhenatherum elatius, a perennial grass with a high biomass production. In heavily polluted soils, while Zn bioaccumulation is weak, A. elatius accumulates more Cd than reported gramineous plants, with concentration of up to 100 {mu}g g{sup -1}. Our results also showed seasonal variations of bioaccumulation, underlying the necessity for in situ studies to specify the date of sampling and also the phenology of the collected plant sample. In our experimental conditions, accumulation is lower in June, leading us to the hypothesis of restriction in heavy metals translocation from roots to aerial parts during seed production. - Cd and Zn bioaccumulation varies seasonally in a perennial grass.

  9. Diversification of Lupinus (Leguminosae) in the western New World: derived evolution of perennial life history and colonization of montane habitats.

    Science.gov (United States)

    Drummond, Christopher S

    2008-08-01

    Previous phylogenetic studies of Lupinus (Leguminosae) based on nuclear DNA have shown that the western New World taxa form a monophyletic group representing the majority of species in the genus, with evidence for high rates of recent diversification in South America following final uplift of the Andes 2-4 million years ago (Mya). For this study, three regions of rapidly evolving non-coding chloroplast DNA (trnL intron, trnS-trnG, and trnT-trnL) were examined to estimate the timing and rates of diversification in the western New World, and to infer ancestral states for geographic range, life history, and maximum elevation. The western New World species (5.0-9.3Mya, 0.6-1.1 spp./My) comprise a basally branching assemblage of annual plants endemic to the lower elevations of western North America, from which two species-rich clades are recently derived: (i) the western North American perennials from the Rocky Mountains, Great Basin, and Pacific Slope (0.7-2.1Mya, 2.0-5.9 spp./My) and (ii) the predominantly perennial species from the Andes Mountains of South America and highlands of Mexico (0.8-3.4Mya, 1.4-5.7spp./My). Bayesian posterior predictive tests for association between life history and maximum elevation demonstrate that perennials are positively correlated with higher elevations. These results are consistent with a series of one or more recent radiations in the western New World, and indicate that rapid diversification of Lupinus coincides with the derived evolution of perennial life history, colonization of montane habitats, and range expansion from North America to South America. PMID:18534869

  10. Genetic and Environmental Variance Among F2 Families in a Commercial Breeding Program for Perennial Ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Fé, Dario; Greve-Pedersen, Morten; Jensen, Christian Sig

    In the joint project “FORAGESELECT”, we aim to implement Genome Wide Selection (GWS) in breeding of perennial ryegrass (Lolium perenne L.), in order to increase genetic response in important agronomic traits such as yield, seed production, stress tolerance and disease resistance, while decreasing...... programs based on GWS. Future work will focus on developing association models based on tailored phenotype data and genotype-by-sequencing-derived allele frequencies...

  11. Randomised controlled trial of homoeopathy versus placebo in perennial allergic rhinitis with overview of four trial series

    OpenAIRE

    Taylor, M. A.; Reilly, D.; Llewellyn-Jones, R.H.; McSharry, C; Aitchison, T

    2000-01-01

    OBJECTIVE: To test the hypothesis that homoeopathy is a placebo by examining its effect in patients with allergic rhinitis and so contest the evidence from three previous trials in this series. Design: Randomised, double blind, placebo controlled, parallel group, multicentre study. SETTING: Four general practices and a hospital ear, nose, and throat outpatient department. PARTICIPANTS: 51 patients with perennial allergic rhinitis. Intervention: Random assignment to an oral 30c h...

  12. Study of Potential and Real Seed Producing Capacity in Some Romanian Varieties of Legumes and Perennial Gramineae

    Directory of Open Access Journals (Sweden)

    Neculai Dragomir

    2010-10-01

    Full Text Available This work presents the potential and real seed producing capacity in some Romanian varieties of legumes and perennial gramineae: Trifolium repens, Lotus corniculatus, Lolium perenne, Festuca pratensis, Festuca arundinacea and Dactylis glomerata. To calculate the potential production, we performed determinations and analyses on each variety, regarding floral apparatus’ morphological and anatomic structure (number of inflorescences, number of flowers, number of ovules/ovary, and the real production was determined „in situ”.

  13. Seasonal Variation in Total Phenolic and Flavonoid Contents and DPPH Scavenging Activity of Bellis perennis L. Flowers

    OpenAIRE

    Tomáš Siatka; Marie Kašparová

    2010-01-01

    Variations in total phenolic and flavonoid contents as well as antioxidant activity of Bellis perennis (common daisy) flowers were investigated. The flowers were collected monthly (from March to October, i.e., during the usual flowering season of the plant) at three localities in three different years. Total flavonoids were determined spectrophotometrically by two methods: by formation of a complex with aluminium chloride after acidic hydrolysis of flower extracts (method 1) and by reaction w...

  14. Global climate niche estimates for bioenergy crops and invasive species of agronomic origin: potential problems and opportunities.

    Directory of Open Access Journals (Sweden)

    Jacob N Barney

    Full Text Available The global push towards a more biomass-based energy sector is ramping up efforts to adopt regionally appropriate high-yielding crops. As potential bioenergy crops are being moved around the world an assessment of the climatic suitability would be a prudent first step in identifying suitable areas of productivity and risk. Additionally, this assessment also provides a necessary step in evaluating the invasive potential of bioenergy crops, which present a possible negative externality to the bioeconomy. Therefore, we provide the first global climate niche assessment for the major graminaceous (9, herbaceous (3, and woody (4 bioenergy crops. Additionally, we contrast these with climate niche assessments for North American invasive species that were originally introduced for agronomic purposes as examples of well-intentioned introductions gone awry. With few exceptions (e.g., Saccharum officinarum, Pennisetum purpureum, the bioenergy crops exhibit broad climatic tolerance, which allows tremendous flexibility in choosing crops, especially in areas with high summer rainfall and long growing seasons (e.g., southeastern US, Amazon Basin, eastern Australia. Unsurprisingly, the invasive species of agronomic origin have very similar global climate niche profiles as the proposed bioenergy crops, also demonstrating broad climatic tolerance. The ecoregional evaluation of bioenergy crops and known invasive species demonstrates tremendous overlap at both high (EI≥30 and moderate (EI≥20 climate suitability. The southern and western US ecoregions support the greatest number of invasive species of agronomic origin, especially the Southeastern USA Plains, Mixed Woods Plains, and Mediterranean California. Many regions of the world have a suitable climate for several bioenergy crops allowing selection of agro-ecoregionally appropriate crops. This model knowingly ignores the complex biotic interactions and edaphic conditions, but provides a robust assessment of

  15. Chemical Ceratoides, Years Composition and Ruminal Digestibility of a Salt-tolerant Perennial Plant,at Different

    Institute of Scientific and Technical Information of China (English)

    SUN H; ISHIKAWA N; VIN G; SHIMIZU K; CAO W; Hasiqiqige; AMARI M; Alata

    2012-01-01

    It has been proposed that salt-tolerant plant could be used as a feed resource for ruminants whereby salt would be removed from salinized land (Asian-Aust. J. Anim. Sci. (2002) 15:998-1001). Ceratoides arborescens (Losinsk.) Tsien et C. G. Ma is known as a drought- and salt-tolerant plant,a kind of shrubs, growing in semi-arid land of Inner Mongolia. Because the covering effect of the perennial plant as a mulch over the soil might be expected, the optimum covering effect would be obtained after the growth period.The perennial plant produces seeds around summer and end its growth thereafter. Nutrient value of the perennial salt-tolerant plant, however, had not been reported in flowering period at different year. It is necessary to know the ruminal degradability of the plants of each growing year in order to determine the regimen to diet for ruminants. The present experiment,therefore,was undertaken to analyze the digestibility and chemical composition of Ceratoides arborescens as feed for ruminants.

  16. Functional characterization and hormonal regulation of the PHEOPHYTINASE gene LpPPH controlling leaf senescence in perennial ryegrass.

    Science.gov (United States)

    Zhang, Jing; Yu, Guohui; Wen, Wuwu; Ma, Xiqing; Xu, Bin; Huang, Bingru

    2016-02-01

    Chlorophyll (Chl) degradation occurs naturally during leaf maturation and senescence, and can be induced by stresses, both processes involving the regulation of plant hormones. The objective of this study was to determine the functional roles and hormonal regulation of a gene encoding pheophytin pheophorbide hydrolyase (PPH) that catabolizes Chl degradation during leaf senescence in perennial grass species. A PPH gene, LpPPH, was cloned from perennial ryegrass (Lolium perenne L.). LpPPH was localized in the chloroplast. Overexpressing LpPPH accelerated Chl degradation in wild tobacco, and rescued the stay-green phenotype of the Arabidopsis pph null mutant. The expression level of LpPPH was positively related to the extent of leaf senescence. Exogenous application of abscisic acid (ABA) and ethephon (an ethylene-releasing agent) accelerated the decline in Chl content in leaves of perennial ryegrass, whereas cytokinin (CK) and aminoethoxyvinylglycine (AVG; an ethylene biosynthesis inhibitor) treatments suppressed leaf senescence, corresponding to the up- or down-regulation of LpPPH expression. The promoters of five orthologous PPH genes were predicted to share conserved cis-elements potentially recognized by transcription factors in the ABA and CK pathways. Taken together, the results suggested that LpPPH-mediated Chl breakdown could be regulated positively by ABA and ethylene, and negatively by CK, and LpPPH could be a direct downstream target gene of transcription factors in the ABA and CK signaling pathways. PMID:26643195

  17. Intranasal cold dry air is superior to histamine challenge in determining the presence and degree of nasal hyperreactivity in nonallergic noninfectious perennial rhinitis

    NARCIS (Netherlands)

    J.P. Braat (Joseph); W.J. Fokkens (Wytske); R. Gerth van Wijk (Roy); E. Rijntjes; P.G.H. Mulder (Paul)

    1998-01-01

    textabstractThe objective of the study was to compare cold dry air (CDA) and histamine in differentiating patients with nonallergic noninfectious perennial rhinitis (NANIPER) from control subjects. Nasal reactivity (nasal patency, mucus production, and sneezing) in 16 s

  18. Assessment of Carbon Sequestration in German Alley Cropping Systems

    Science.gov (United States)

    Tsonkova, P. B.; Quinkenstein, A.; Böhm, C.; Freese, D.

    2012-04-01

    Alley cropping systems (ACS) are agroforestry practices in which perennial trees or shrubs are grown in wide rows and arable crops are cultivated in the alleys between the tree rows. Recently, ACS which integrate stripes of short rotation coppices into conventional agricultural sites have gained interest in Germany. These systems can be used for simultaneous production of crops and woody biomass which enables farmers to diversify the provision of market goods. Adding trees into the agricultural landscape creates additional benefits for the farmer and society also known as ecosystem services. An ecosystem service provided by land use systems is carbon sequestration. The literature indicates that ACS are able to store more carbon compared to agriculture and their implementation may lead to greater benefits for the environment and society. Moreover, carbon sequestration in ACS could be included in carbon trading schemes and farmers rewarded additionally for the provision of this ecosystem service. However, methods are required which are easy to use and provide reliable information regarding change in carbon sequestration with change of the land use practice. In this context, our aim was to develop a methodology to assess carbon sequestration benefit provided by ACS in Germany. Therefore, the change of carbon in both soil and biomass had to be considered. To predict the change in soil carbon our methodology combined the 2006 IPCC Guidelines for National Greenhouse Gas Inventories and the soil organic carbon balance recommended by the Association of German Agricultural Investigation and Research Centers (VDLUFA). To reflect the change in biomass carbon average annual yields were adopted. The results showed that ACS established on agricultural sites can increase the carbon stored because in the new soil-plant system carbon content is higher compared to agriculture. ACS have been recommended as suitable land use systems for marginal sites, such as post-mining areas. In

  19. Quantifying biological nitrogen fixation of different catch crops, and residual effects of roots and tops on nitrogen uptake in barley using in-situ 15N labelling

    DEFF Research Database (Denmark)

    Li, Xiaoxi; Sørensen, Peter; Li, F C;

    2015-01-01

    Contributions of legume-based catch crops (LBCCs) to succeeding cereals may be significant. We quantified biological N fixation (BNF) and residual N effects of contrasting CC tops and roots. Methods BNF of three LBCCs (red clover, winter vetch, perennial ryegrass-red clover mixture) was quantified...... N uptake was derived from non-LBCCs. The 15N-based N fertiliser values of LBCC tops were 34–47 % against 26–29 % for non-LBCCs. LBCC roots contributed substantial amounts of N to the system, a source that is usually underestimated. N immobilisation after incorporation of non-LBCCs may hamper...

  20. 75 FR 65995 - Biomass Crop Assistance Program

    Science.gov (United States)

    2010-10-27

    ..., fertilizers, pesticides, energy for irrigation), on-site fossil fuel emissions, on-site soil carbon dioxide (CO 2 ) emissions from organic carbon (soil organic matter and plant residue) and inorganic carbon... soil organic matter and the presence of perennial vegetation. The use of BMPs would further reduce...