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Sample records for leguminous cover crop

  1. The role of leguminous cover crops in sustainable production of oil ...

    African Journals Online (AJOL)

    Leguminous cover crops have the potential for obtaining high and sustainable crop yields. They have been shown to play an important role in weed suppression, nutrition, growth and yield of oil palm. They also play an important role in soil erosion control and soil moisture conservation in plantations. The development of ...

  2. Can leguminous cover crops partially replace nitrogen fertilization in Mississippi delta cotton production

    Science.gov (United States)

    Petroleum prices impacts cotton (Gossypium hirsutum L.) N fertilization cost. A 3-year field study was conducted on a Dundee silt loam to assess the interactions of leguminous cover crops [none, Austrian winter field pea (Pisum sativum L.) or hairy vetch (Vicia villosa Roth] and N fertilization rate...

  3. Effect of leguminous cover crops on soil biological activity in pots of Citrus unshiu Marcovitch

    Directory of Open Access Journals (Sweden)

    Cristina Abbate

    2011-02-01

    Full Text Available Little is known about the effects of cover crops on soil properties in citrus orchards. To fill this gap, this work was aimed to determine the effects of leguminous cover crops on the chemical and biological properties of the soil and on the structure of the microbial community in pots of Citrus unshiu (Marcovitch. After amendment with cover crops, an increase in total organic C (TOC, total extractable C (TEC, and total N (TN contents were observed irrespective of the type of soil. Substrate induced respiration (SIR, and potentially mineralisable nitrogen (PMN, tested three times in one year, were higher in soils with leguminous cover crops while no significant differences were observed in protease and deaminase activity. The effect on the chemical and biochemical properties of the soil was more evident in plots containing Trifolium subterraneum. No changes were observed in the microbial communities studied (_-proteobacteria, _-proteobacteria, nitrogen-fixing, and ammonia oxidizers irrespective of the kind of cover crop or type of soil, neither were variations noted during the trial.

  4. Environmental impact of almond crop in strong slope with two vegetable covers: bush and leguminous

    International Nuclear Information System (INIS)

    Carceles Rodriguez, B.; Francia Martinez, J. R.; Martinez Raya, A.

    2009-01-01

    Soil erosion is one of the main physical processes of land degradation in Spain. Several studies in the Mediterranean environment have demonstrated the positive effect of vegetation covers on the reduction of water erosion and their indirect improvement of the soil physical and chemical properties, essentially by the incorporation of organic matter. Sol loss and surface runoff patterns over a four-year period were monitors in erosion plots from hill slope with two different cover-crop strips: (1) non-tillage with leguminous (Lens esculenta Moench) and (2) non-tillage with and a mixture of autochthonous thymes (Thymus baeticus Boiss. ex Lacaita, Thymus capitatus (L) Hoffmanns and Link., Thymus vulgaris L.) of 3 m with, in Lanjaron (Granada) on the south flank of the Sierra Nevada of southeast Spain. The erosion plots were located on the hill slope at 35% incline, at 580 m in altitude and with 144 m 2 (24 m x 6 m) in area. the area selected for the experiment is the part of the rainfed orchard given entirely with almond (Prunus amygdalus Basch cv. Desmayo Largueta) trees, the planting gird were 6 x 7 m. (Author) 10 refs.

  5. LEGUMINOUS COVER CROPS FOR BANANA PLANTATIONS IN SEMI-ARID REGIONS

    Directory of Open Access Journals (Sweden)

    MATEUS AUGUSTO LIMA QUARESMA

    2017-01-01

    Full Text Available High temperatures and low rainfall characterize the Brazilian semiarid regions. This regional climate demands the adoption of practices that increase the efficiency and sustainability of local farming. This study aimed to assess the ability of two perennial herbaceous leguminous species, calopo and tropical kudzu, to provide permanent soil cover in banana plantations in Jequitinhonha Valley, northeast Minas Gerais state, Brazil. To this end, we evaluated the differences of calopo and tropical kudzu in soil cover capacity and the amount of senescent phytomass deposited on the soil surface, nutrient content in senescent phytomass, as well as their effects on temperature and soil moisture, compared with bare soil in two experimental sites. The results showed that, compared with tropical kudzu, calopo had a higher soil cover capacity and was more effective at increasing organic material and nutrients in the soil owing to the relatively higher amount of senescent phytomass deposited on the soil surface. However, both calopo and tropical kudzu reduced soil temperature and increase soil moisture compared with bare soil. Overall, we concluded that these species can deposit high levels of senescence in the soil, providing several benefits to the cultivation system of banana plants in the semiarid regions.

  6. Potential of Leguminous Cover Crops in Management of a Mixed Population of Root-knot Nematodes (Meloidogyne spp.).

    Science.gov (United States)

    Osei, Kingsley; Gowen, Simon R; Pembroke, Barbara; Brandenburg, Rick L; Jordan, David L

    2010-09-01

    Root-knot nematode is an important pest in agricultural production worldwide. Crop rotation is the only management strategy in some production systems, especially for resource poor farmers in developing countries. A series of experiments was conducted in the laboratory with several leguminous cover crops to investigate their potential for managing a mixture of root-knot nematodes (Meloidogyne arenaria, M. incognita, M. javanica). The root-knot nematode mixture failed to multiply on Mucuna pruriens and Crotalaria spectabilis but on Dolichos lablab the population increased more than 2- fold when inoculated with 500 and 1,000 nematodes per plant. There was no root-galling on M. pruriens and C. spectabilis but the gall rating was noted on D. lablab. Greater mortality of juvenile root-knot nematodes occurred when exposed to eluants of roots and leaves of leguminous crops than those of tomato; 48.7% of juveniles died after 72 h exposure to root eluant of C. spectabilis. The leaf eluant of D. lablab was toxic to nematodes but the root eluant was not. Thus, different parts of a botanical contain different active ingredients or different concentrations of the same active ingredient. The numbers of root-knot nematode eggs that hatched in root exudates of M. pruriens and C. spectabilis were significantly lower (20% and 26%) than in distilled water, tomato and P. vulgaris root exudates (83%, 72% and 89%) respectively. Tomato lacks nematotoxic compounds found in M. pruriens and C. spectabilis. Three months after inoculating plants with 1,000 root-knot nematode juveniles the populations in pots with M. pruriens, C. spectabilis and C. retusa had been reduced by approximately 79%, 85% and 86% respectively; compared with an increase of 262% nematodes in pots with Phaseolus vulgaris. There was significant reduction of 90% nematodes in fallow pots with no growing plant. The results from this study demonstrate that some leguminous species contain compounds that either kill root

  7. Roots of symptom-free leguminous cover crop and living mulch species harbor diverse Fusarium communities that show highly variable aggressiveness on pea (Pisum sativum)

    Science.gov (United States)

    Baćanović-Šišić, Jelena; Karlovsky, Petr; Wittwer, Raphaël; Walder, Florian; Campiglia, Enio; Radicetti, Emanuele; Friberg, Hanna; Baresel, Jörg Peter; Finckh, Maria R.

    2018-01-01

    Leguminous cover crop and living mulch species show not only great potential for providing multiple beneficial services to agro-ecosystems, but may also present pathological risks for other crops in rotations through shared pathogens, especially those of the genus Fusarium. Disease severity on roots of subterranean clover, white clover, winter and summer vetch grown as cover crop and living mulch species across five European sites as well as the frequency, distribution and aggressiveness to pea of Fusarium spp. recovered from the roots were assessed in 2013 and 2014. Disease symptoms were very low at all sites. Nevertheless, out of 1480 asymptomatic roots, 670 isolates of 14 Fusarium spp. were recovered. The most frequently isolated species in both years from all hosts were F. oxysporum and F. avenaceum accounting for 69% of total isolation percentage. They were common at the Swiss, Italian and German sites, whereas at the Swedish site F. oxysporum dominated and F. avenaceum occurred only rarely. The agressiveness and effect on pea biomass were tested in greenhouse assays for 72 isolates of six Fusarium species. Isolates of F. avenaceum caused severe root rot symptoms with mean severity index (DI) of 82 and 74% mean biomass reduction compared to the non-inoculated control. Fusarium oxysporum and F. solani isolates were higly variable in agressiveness and their impact on pea biomass. DI varied between 15 and 50 and biomass changes relative to the non-inoculated control -40% to +10%. Isolates of F. tricinctum, F. acuminatum and F. equiseti were non to weakly agressive often enhancing pea biomass. This study shows that some of the major pea pathogens are characterized by high ecological plasticity and have the ability to endophytically colonize the hosts studied that thus may serve as inoculum reservoir for susceptible main legume grain crops such as pea. PMID:29444142

  8. Roots of symptom-free leguminous cover crop and living mulch species harbor diverse Fusarium communities that show highly variable aggressiveness on pea (Pisum sativum).

    Science.gov (United States)

    Šišić, Adnan; Baćanović-Šišić, Jelena; Karlovsky, Petr; Wittwer, Raphaël; Walder, Florian; Campiglia, Enio; Radicetti, Emanuele; Friberg, Hanna; Baresel, Jörg Peter; Finckh, Maria R

    2018-01-01

    Leguminous cover crop and living mulch species show not only great potential for providing multiple beneficial services to agro-ecosystems, but may also present pathological risks for other crops in rotations through shared pathogens, especially those of the genus Fusarium. Disease severity on roots of subterranean clover, white clover, winter and summer vetch grown as cover crop and living mulch species across five European sites as well as the frequency, distribution and aggressiveness to pea of Fusarium spp. recovered from the roots were assessed in 2013 and 2014. Disease symptoms were very low at all sites. Nevertheless, out of 1480 asymptomatic roots, 670 isolates of 14 Fusarium spp. were recovered. The most frequently isolated species in both years from all hosts were F. oxysporum and F. avenaceum accounting for 69% of total isolation percentage. They were common at the Swiss, Italian and German sites, whereas at the Swedish site F. oxysporum dominated and F. avenaceum occurred only rarely. The agressiveness and effect on pea biomass were tested in greenhouse assays for 72 isolates of six Fusarium species. Isolates of F. avenaceum caused severe root rot symptoms with mean severity index (DI) of 82 and 74% mean biomass reduction compared to the non-inoculated control. Fusarium oxysporum and F. solani isolates were higly variable in agressiveness and their impact on pea biomass. DI varied between 15 and 50 and biomass changes relative to the non-inoculated control -40% to +10%. Isolates of F. tricinctum, F. acuminatum and F. equiseti were non to weakly agressive often enhancing pea biomass. This study shows that some of the major pea pathogens are characterized by high ecological plasticity and have the ability to endophytically colonize the hosts studied that thus may serve as inoculum reservoir for susceptible main legume grain crops such as pea.

  9. Bioactivity of flours of seeds of leguminous crops Pisum sativum ...

    African Journals Online (AJOL)

    Bioactivity of flours of seeds of leguminous crops Pisum sativum, Phaseolus vulgaris and Glycine max used as botanical insecticides against Sitophilus oryzae Linnaeus (Coleoptera: Curculionidae) on sorghum grains.

  10. Ambient and elevated carbon dioxide on growth, physiological and nutrient uptake parameters of perennial leguminous cover crops under low light intensities

    Science.gov (United States)

    Adaptability and optimum growth of cover crops in plantation crops is affected by the inherent nature of the cover crop species and the light intensity at canopy levels. Globally concentrations of atmospheric CO2 are increasing and this creates higher photosynthesis and nutrient demand by crops as l...

  11. Environmental impact of almond crop in strong slope with two vegetable covers: bush and leguminous; Impacto en el medio ambiente del cultivo de almendros en fuertes pendientes con dos cubiertas vegetales: Matorral y Leguminosa

    Energy Technology Data Exchange (ETDEWEB)

    Carceles Rodriguez, B.; Francia Martinez, J. R.; Martinez Raya, A.

    2009-07-01

    Soil erosion is one of the main physical processes of land degradation in Spain. Several studies in the Mediterranean environment have demonstrated the positive effect of vegetation covers on the reduction of water erosion and their indirect improvement of the soil physical and chemical properties, essentially by the incorporation of organic matter. Sol loss and surface runoff patterns over a four-year period were monitors in erosion plots from hill slope with two different cover-crop strips: (1) non-tillage with leguminous (Lens esculenta Moench) and (2) non-tillage with and a mixture of autochthonous thymes (Thymus baeticus Boiss. ex Lacaita, Thymus capitatus (L) Hoffmanns and Link., Thymus vulgaris L.) of 3 m with, in Lanjaron (Granada) on the south flank of the Sierra Nevada of southeast Spain. The erosion plots were located on the hill slope at 35% incline, at 580 m in altitude and with 144 m{sup 2} (24 m x 6 m) in area. the area selected for the experiment is the part of the rainfed orchard given entirely with almond (Prunus amygdalus Basch cv. Desmayo Largueta) trees, the planting gird were 6 x 7 m. (Author) 10 refs.

  12. Improved Crotalaria cover crop fallow system for sustainable maize ...

    African Journals Online (AJOL)

    An on-station trial was carried out at the Research Farm of the Faculty of Agriculture, University for Development Studies, Tamale, in the northern Guinea Savanna agroecological zone of Ghana. The study compared different seeding rates of leguminous cover crops, inorganic fertilization, and a combination of the two in a ...

  13. ANTIOXIDANT, ANTI-INFLAMMATORY ACTIVITY OF GEORGIAN LEGUMINOUS CROPS CULTURES.

    Science.gov (United States)

    Chkhikvishvili, I; Mamniashvili, T; Gogia, N; Enukidze, M; Machavariani, M; Sanikidze, T

    2017-11-01

    The aim of the study was to identify the common in Georgia leguminous crops culture with pronounced antioxidant, anti-inflammatory activity. The primary evaluation of the antiinflammatory effects of beans was performed on the experimental models of MDCK and Jurkat cells model systems. Extracts of various varieties of legumes (Beans "Kidney", Meadow beans, Beans Shulavera, Batumian beans, Beans "Udelebi", green peas, peas Shulavera, lentils Lens Culinaris, Soy) were added to the intact or incubated under oxidative stress conditions Jurkat and MDCK cells. Cells' vitality was determined by MTT test. On the basis of analysis of the obtained results, we concluded that: - Meadow beans extract (low doses) revealed cytoprotective effect on the intact and incubated under oxidative stress conditions immune (Jurkat) and epithelial (MDCK) cells. High antioxidant, cytoprotective activity of this extract correlates with high polyphenols content in it. - The extract of Shulavera beans did affect the intact Jurkat and MDCK cells, but showed pronounced cytoprotective activity on these cells incubated under the oxidative stress conditions. High antioxidant, cytoprotective activity of this extract correlates with high content of polyphenols in it. - Low dose of lentils Lens Culinaris extracts revealed cytoprotective activity on the incubated under oxidative stress conditions MDCK cells, but was inactive in case of intact MDCK and incubated in different conditions immune Jurkat cells. The selective antioxidant activity of this extract is related with its other constituent components, but not polyphenols. - Despite high polyphenols content and high antioxidant activity in vivo, Batumian beans revealed moderate cytoprotective activity on intact and incubated under oxidative stress conditions Jurkat cells, suppressive activity on the intact MDCK cells and was inactive in relation to the incubated under oxidative stress conditions MDCK cells. Based on these findings, we can identify

  14. Topography Mediates the Influence of Cover Crops on Soil Nitrate Levels in Row Crop Agricultural Systems.

    Science.gov (United States)

    Ladoni, Moslem; Kravchenko, Alexandra N; Robertson, G Phillip

    2015-01-01

    Supplying adequate amounts of soil N for plant growth during the growing season and across large agricultural fields is a challenge for conservational agricultural systems with cover crops. Knowledge about cover crop effects on N comes mostly from small, flat research plots and performance of cover crops across topographically diverse agricultural land is poorly understood. Our objective was to assess effects of both leguminous (red clover) and non-leguminous (winter rye) cover crops on potentially mineralizable N (PMN) and [Formula: see text] levels across a topographically diverse landscape. We studied conventional, low-input, and organic managements in corn-soybean-wheat rotation. The rotations of low-input and organic managements included rye and red clover cover crops. The managements were implemented in twenty large undulating fields in Southwest Michigan starting from 2006. The data collection and analysis were conducted during three growing seasons of 2011, 2012 and 2013. Observational micro-plots with and without cover crops were laid within each field on three contrasting topographical positions of depression, slope and summit. Soil samples were collected 4-5 times during each growing season and analyzed for [Formula: see text] and PMN. The results showed that all three managements were similar in their temporal and spatial distributions of NO3-N. Red clover cover crop increased [Formula: see text] by 35% on depression, 20% on slope and 32% on summit positions. Rye cover crop had a significant 15% negative effect on [Formula: see text] in topographical depressions but not in slope and summit positions. The magnitude of the cover crop effects on soil mineral nitrogen across topographically diverse fields was associated with the amount of cover crop growth and residue production. The results emphasize the potential environmental and economic benefits that can be generated by implementing site-specific topography-driven cover crop management in row-crop

  15. Topography Mediates the Influence of Cover Crops on Soil Nitrate Levels in Row Crop Agricultural Systems.

    Directory of Open Access Journals (Sweden)

    Moslem Ladoni

    Full Text Available Supplying adequate amounts of soil N for plant growth during the growing season and across large agricultural fields is a challenge for conservational agricultural systems with cover crops. Knowledge about cover crop effects on N comes mostly from small, flat research plots and performance of cover crops across topographically diverse agricultural land is poorly understood. Our objective was to assess effects of both leguminous (red clover and non-leguminous (winter rye cover crops on potentially mineralizable N (PMN and [Formula: see text] levels across a topographically diverse landscape. We studied conventional, low-input, and organic managements in corn-soybean-wheat rotation. The rotations of low-input and organic managements included rye and red clover cover crops. The managements were implemented in twenty large undulating fields in Southwest Michigan starting from 2006. The data collection and analysis were conducted during three growing seasons of 2011, 2012 and 2013. Observational micro-plots with and without cover crops were laid within each field on three contrasting topographical positions of depression, slope and summit. Soil samples were collected 4-5 times during each growing season and analyzed for [Formula: see text] and PMN. The results showed that all three managements were similar in their temporal and spatial distributions of NO3-N. Red clover cover crop increased [Formula: see text] by 35% on depression, 20% on slope and 32% on summit positions. Rye cover crop had a significant 15% negative effect on [Formula: see text] in topographical depressions but not in slope and summit positions. The magnitude of the cover crop effects on soil mineral nitrogen across topographically diverse fields was associated with the amount of cover crop growth and residue production. The results emphasize the potential environmental and economic benefits that can be generated by implementing site-specific topography-driven cover crop management

  16. Climate Impacts of Cover Crops

    Science.gov (United States)

    Lombardozzi, D.; Wieder, W. R.; Bonan, G. B.; Morris, C. K.; Grandy, S.

    2016-12-01

    Cover crops are planted in agricultural rotation with the intention of protecting soil rather than harvest. Cover crops have numerous environmental benefits that include preventing soil erosion, increasing soil fertility, and providing weed and pest control- among others. In addition to localized environmental benefits, cover crops can have important regional or global biogeochemical impacts by increasing soil organic carbon, changing emissions of greenhouse trace gases like nitrous oxide and methane, and reducing hydrologic nitrogen losses. Cover crops may additionally affect climate by changing biogeophysical processes, like albedo and latent heat flux, though these potential changes have not yet been evaluated. Here we use the coupled Community Atmosphere Model (CAM5) - Community Land Model (CLM4.5) to test how planting cover crops in the United States may change biogeophysical fluxes and climate. We present seasonal changes in albedo, heat fluxes, evaporative partitioning, radiation, and the resulting changes in temperature. Preliminary analyses show that during seasons when cover crops are planted, latent heat flux increases and albedo decreases, changing the evaporative fraction and surface temperatures. Understanding both the biogeophysical changes caused by planting cover crops in this study and the biogeochemical changes found in other studies will give a clearer picture of the overall impacts of cover crops on climate and atmospheric chemistry, informing how this land use strategy will impact climate in the future.

  17. Sustainable Agriculture: Cover Cropping

    Science.gov (United States)

    Webster, Megan

    2018-01-01

    Sustainable agriculture practices are increasingly being used by farmers to maintain soil quality, increase biodiversity, and promote production of food that is environmentally safe. There are several types of sustainable agriculture practices such as organic farming, crop rotation, and aquaculture. This lesson plan focuses on the sustainable…

  18. Enhancing the biological nitrogen fixation of leguminous crops ...

    African Journals Online (AJOL)

    Legumes have the ability to establish a symbiotic interaction with soil bacteria, collectively termed as rhizobia. These bacteria can enhance growth and development of associated crops by transferring atmospheric nitrogen into a form that is available for plant growth or by improving nutrient uptake through modulation of ...

  19. Benefits of Vetch and Rye Cover Crops to Sweet Corn under No-Tillage

    NARCIS (Netherlands)

    Zotarelli, L.; Avila, L.; Scholberg, J.M.S.; Alves, B.J.R.

    2009-01-01

    Leguminous cover crops (CCs) may reduce N fertilizer requirements by fixing N biologically and storing leftover N-fertilizer applied in the previous year. The objective of this study was to determine the contribution of CCs [rye (Secale cereal L.) and hairy vetch (Vicia villosa Roth)] on plant N

  20. Rye cover crop effects on nitrous oxide emissions from a corn-soybean system

    Science.gov (United States)

    Agricultural activities are a major source nitrous oxide emitted to the atmosphere. Development of management practices to reduce these emissions is needed. Non-leguminous cover crops are efficient scavengers of residual soil nitrate, but their effects on nitrous oxide emissions have not been well d...

  1. Aluminium tolerance of Mucuna : A tropical leguminous cover crop

    NARCIS (Netherlands)

    Hairiah, Kurniatun

    1992-01-01

    In the humid tropics leaching of N and other nutrients to the subsoil may occur throughout the growing season. Typically, soils in this zone have a low soil pH, a high Al saturation of the cation exchange complex and low levels of Ca and P in the subsoil. Efficiency of N-use under such conditions

  2. Barcoding the major Mediterranean leguminous crops by combining universal chloroplast and nuclear DNA sequence targets.

    Science.gov (United States)

    Madesis, P; Ganopoulos, I; Ralli, P; Tsaftaris, A

    2012-08-16

    The ability to discriminate all species is the ultimate target in barcoding. The Mediterranean basin is a center of origin for legumes and thus they have played a key role in feeding the Mediterranean population. It is also a region with important protected designation of origin and protected geographical indication legumes that provide income in rural areas. We evaluated the use of two chloroplast regions, trnL and rpoC1, and a nuclear internal transcriber region, ITS2, for their efficiency to barcode the main Mediterranean leguminous crops. Twenty-five legume species were studied. Plant material of pasture and legumes was obtained from the Greek GenBank and the Fodder Crops and Pastures Institute (National Agricultural Research Foundation). DNA was extracted with the Qiagen DNeasy plant mini-kit and PCR amplification was performed using the Kapa Taq DNA polymerase using primers amplifying the chloroplast trnL and rpoC1 regions or the nuclear region ITS2. PCR products were sequenced and the sequences were aligned using CLUSTAL W. Species identification based on the sequence similarity approach was performed using the GenBank database. In order to evaluate intraspecific and interspecific divergence in legumes we used Molecular Evolutionary Genetics Analysis 5 and for pairwise Kimura 2-parameter distance calculations for all 3 DNA regions (2 chloroplast regions, trnL and rpoC1, and the nuclear region ITS2). Four tree-based methods (neighbor joining and maximum parsimony, maximum likelihood, and Bayesian inference analyses) were used to exhibit the molecular identification results to represent differences as an uprooted dendrogram. Additionally, the sequence character-based method was used with DnaSP and the information from each site was treated as a character to distinguish the species from one another. The DNA regions trnL and ITS2 successfully (100%) discriminated the Mediterranean crop legume species used, while rpoC1 identified only 72% of them. Furthermore

  3. Combined effect of soil amendment with oil cakes and seed priming in the control of root rot fungi of leguminous and non-leguminous crops

    International Nuclear Information System (INIS)

    Rafi, H.; Dawar, S.; Tariq, M.

    2016-01-01

    Organic amendments of soil help in proper aeration, rising of temperature and water holding capacity which results in better uptake of nutrients with root system gets extensive establishment. In this study, effects of soil amendment with oil seed cakes including mustard (Brassica campestris L.), cotton (Gossypium hirsutum L.), almond (Prunus amygdalus L.) and black seed (Nigella sativa L.) cakes at the rate of 0.1 and 1% w/w and priming of seeds with Acacia nilotica (L.) Willd. ex Delile and Sapindus mukorossi (L.) leaves extracts and microbial antagonists (Trichoderma harzianum and Rhizobium melilotii) was observed on the growth of plants and in the suppression of root infecting fungi. The results obtained showed that combined effect of bio-priming of seeds with T. harzianum spore suspension and amendment of soil with mustard cake at the rate of 1% was found to be most effective for the growth of leguminous and non-leguminous crop plants (peanut, chickpea, okra and sunflower) and for the reduction of root infecting fungi like Macrophomina phaseolina, Fusarium spp followed by R. meliloti primed seeds in combination with cotton, almond and black seed cakes amendment respectively as compared to control (non treated seeds and soil). (author)

  4. Cover crops support ecological intensification of arable cropping systems

    Science.gov (United States)

    Wittwer, Raphaël A.; Dorn, Brigitte; Jossi, Werner; van der Heijden, Marcel G. A.

    2017-02-01

    A major challenge for agriculture is to enhance productivity with minimum impact on the environment. Several studies indicate that cover crops could replace anthropogenic inputs and enhance crop productivity. However, so far, it is unclear if cover crop effects vary between different cropping systems, and direct comparisons among major arable production systems are rare. Here we compared the short-term effects of various cover crops on crop yield, nitrogen uptake, and weed infestation in four arable production systems (conventional cropping with intensive tillage and no-tillage; organic cropping with intensive tillage and reduced tillage). We hypothesized that cover cropping effects increase with decreasing management intensity. Our study demonstrated that cover crop effects on crop yield were highest in the organic system with reduced tillage (+24%), intermediate in the organic system with tillage (+13%) and in the conventional system with no tillage (+8%) and lowest in the conventional system with tillage (+2%). Our results indicate that cover crops are essential to maintaining a certain yield level when soil tillage intensity is reduced (e.g. under conservation agriculture), or when production is converted to organic agriculture. Thus, the inclusion of cover crops provides additional opportunities to increase the yield of lower intensity production systems and contribute to ecological intensification.

  5. Biological fixation of nitrogen in three tropical feed crops leguminous and its transfer to Brachiaria humidicola in association

    International Nuclear Information System (INIS)

    Gil, Jose Luis; Guenni, Orlando; Espinoza, Yusmary

    1997-01-01

    In Cojedes State drained savannas an experiment was carried out with the purpose of: a) to determine the biological fixation of nitrogen (BFN) in three tropical feed crops leguminous (Centrosema pubescens Cp, Stylosanthes hamata Sh and Pueraria phaseoloides, Pp) cultivated in monoculture and associated with the gramineous Brachiaria humidicola (Bh); b) to evaluate the transfer potential of N fixed to the air to the companion gramineous. To calculate the proportion of N biologically fixed, the technique of isotopic dilution was used with N 1 5. The fertilizer (enriched ammonium sulphate to 10% with N 1 5) was added during the rainy season in two regrowth periods. In each case, the aerial biomass was determined after 90 days of growth, being analyzed the total content of N and N 1 5 in the foliage. In both periods of evaluation, the association Bh / Cp was stabler, with a proportion of the leguminous in the mixture 20-30%. As monoculture, Bh had the biggest production of aerial biomass (972 gm -2 ) among all the treatments for the first period of evaluation (middle rainy season). The total production of dry matter (DM) in association, was modified between 574 (Bh/Cp) and 807 gm -2 (Bh/Sh). The production DM for the second period of evaluation (end rainy season) followed the same tendency, being observed, however, a general decrease in the yields due to the beginning of drought. The content of N in the leguminous was always higher than in Bh. Nevertheless, Bh in association reached an accumulation bigger than N (14 gm -2 ) due to its higher rate of growth. The leguminous alone had a significant proportion of N (47-69%) derivated of the BFN. Cp was the one that showed higher values of BFN (51-69%). Likewise, one observes a high proportion (57-76%) of element starting from the BFN when the leguminous were cultivated in association. In this sense one doesn't observe a clear transfer of N from the leguminous to the gramineous, since the contents of N 1 5 in Bh they were

  6. Managing cover crops on strawberry furrow bottoms

    Science.gov (United States)

    Bare furrows in strawberry fields with plastic mulch covered beds can lead to lots of soil erosion and runoff during winter rainy periods. This article describes how growers can plant and manage cover crops in these furrows to minimize runoff and soil erosion. This is based on on-going research at...

  7. Do cover crop mixtures have the same ability to suppress weeds as competitive monoculture cover crops?

    Directory of Open Access Journals (Sweden)

    Brust, Jochen

    2014-02-01

    Full Text Available An increasing number of farmers use cover crop mixtures instead of monoculture cover crops to improve soil and crop quality. However, only little information is available about the weed suppression ability of cover crop mixtures. Therefore, two field experiments were conducted in Baden-Württemberg between 2010 and 2012, to compare growth and weed suppression of monoculture cover crops and cover crop mixtures. In the first experiment, heterogeneous results between yellow mustard and the cover crop mixture occurred. For further research, a field experiment was conducted in 2012 to compare monocultures of yellow mustard and hemp with three cover crop mixtures. The evaluated mixtures were: “MELO”: for soil melioration; “BETA”: includes only plant species with no close relation to main cash crops in Central Europe and “GPS”: for usage as energy substrate in spring. Yellow mustard, MELO, BETA and GPS covered 90% of the soil in less than 42 days and were able to reduce photosynthetically active radiation (PAR on soil surface by more than 96% after 52 days. Hemp covered 90% of the soil after 47 days and reduced PAR by 91% after 52 days. Eight weeks after planting, only BETA showed similar growth to yellow mustard which produced the highest dry matter. The GPS mixture had comparatively poor growth, while MELO produced similar dry matter to hemp. Yellow mustard, MELO and BETA reduced weed growth by 96% compared with a no cover crop control, while hemp and GPS reduced weeds by 85% and 79%. In spring, weed dry matter was reduced by more than 94% in plots with yellow mustard and all mixtures, while in hemp plots weeds were only reduced by 71%. The results suggest that the tested cover crop mixtures offer similar weed suppression ability until spring as the monoculture of the competitive yellow mustard.

  8. Replacing fallow by cover crops: economic sustainability

    Science.gov (United States)

    Gabriel, José Luis; Garrido, Alberto; Quemada, Miguel

    2013-04-01

    Replacing fallow by cover crops in intensive fertilized systems has been demonstrated as an efficient tool for reducing nitrate leaching. However, despite the evident environmental services provided and the range of agronomic benefits documented in the literature, farmers' adoption of this new technology is still limited because they are either unwilling or unable, although adoption reluctance is frequently rooted in low economic profitability, low water se efficiency or poor knowledge. Economic analyses permit a comparison between the profit that farmers obtain from agricultural products and the cost of adopting specific agricultural techniques. The goal of this study was to evaluate the economic impact of replacing the usual winter fallow with cover crops (barley (Hordeum vulgare L., cv. Vanessa), vetch (Vicia villosa L., cv. Vereda) and rapeseed (Brassica napus L., cv. Licapo)) in irrigated maize systems and variable Mediterranean weather conditions using stochastic Monte-Carlo simulations of key farms' financial performance indicators. The three scenarios studied for each cover crop were: i) just leaving the cover crop residue in the ground, ii) leaving the cover crop residue but reduce following maize fertilization according to the N available from the previous cover crop and iii) selling the cover crop residue for animal feeding. All the scenarios were compared with respect to a typical maize-fallow rotation. With observed data from six different years and in various field trials, looking for different weather conditions, probability distribution functions of maize yield, cover crop biomass production and N fertilizer saving was fitted. Based in statistical sources maize grain price, different forage prices and the cost of fertilizer were fitted to probability distribution functions too. As result, introducing a cover crop involved extra costs with respect to fallow as the initial investment, because new seed, herbicide or extra field operations. Additional

  9. Soybean growth and yield under cover crops

    Directory of Open Access Journals (Sweden)

    Priscila de Oliveira

    2013-04-01

    Full Text Available The use of cover crops in no-tillage systems can provide better conditions for the development of soybean plants with positive effects on grain yield and growth analysis techniques allow researchers to characterize and understand the behavior of soybean plants under different straw covers. Thus, the aim of this study was to characterize, using growth analysis, yield components and agronomic performance of soybean under common bean, Brachiaria brizantha and pearl millet straws. The experiment was performed on a soil under cerrado in the municipality of Santo Antônio de Goiás, GO. The experiment was arranged in a randomized complete block design with three treatments (cover crops and five replications. Soybean grain yield was lower in the B. brizantha straw treatment (3,708 kg ha-1 than both in the pearl millet (4.772 kg ha-1 and common bean straw treatments (5,200 kg ha-1. The soybean growth analysis in B. brizantha, pearl millet and common bean allowed characterizing the variation in the production of dry matter of leaves, stems, pods and total and leaf area index that provided different grain yields. The cover crop directly affects the soybean grain yield.

  10. Development of rapid and highly sensitive detection of Bean common mosaic necrosis virus in leguminous crops using loop-mediated isothermal amplification assay.

    Science.gov (United States)

    Lee, Siwon; Kim, Heejung; Lee, Jin-Young; Rho, Jae-Young

    2017-11-01

    Bean common mosaic necrosis virus (BCMNV) is a plant pathogenic virus that can infect leguminous crops such as kidney beans, sunn hemp, red beans, and mung beans. BCMNV has not been reported in Korea and is classified as a quarantine plant virus. Currently, the standard diagnostic method for diagnosis of BCMNV is reverse transcription (RT)-nested PCR system. However a more rapid monitoring system is needed to enable the testing of more samples. The use of highly efficient loop-mediated isothermal amplification (LAMP) assay for its detection has not yet been reported, and development of LAMP for detecting BCMNV in this study. In addition, confirmation of LAMP amplification can be achieved using restriction enzyme Mse I (T/TAA). The developed technique could be used for more rapid, specific and sensitive monitoring of BCMNV in leguminous crops than conventional nested RT-PCR. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Ecological Considerations in the Selection of Leguminous Plants as ...

    African Journals Online (AJOL)

    Experiments were conducted in 2003 and 2004 to select leguminous cover crops for the Accra plains ecology in Ghana, based on the ability to withstand drought, produce enough biomass and fix nitrogen. In a randomised complete block design, Crotalaria ochroleuca, Stylosanthes ha-mata, Stylosanthes guianensis, ...

  12. A suggestion for planning cover crop mixtures: zones of occupancy

    Science.gov (United States)

    Producers may be able to improve the competitiveness of cover crop mixtures by selecting species to occupy zones in the cover crop canopy. This suggestion is based on a study where we compared four cover crop treatments, 1, 3, 6, and 9 species mixtures, for biomass production. Treatments were est...

  13. Feasibility of winter cover crop production under rainfed conditions

    African Journals Online (AJOL)

    ACSS

    Interaction effects of planting date and cover crop species on cover crop dry weight at termination in Eastern Cape. Province, South Africa. Cover crop dry weight (kg ha. -1. ) 0. 1000. 2000. 3000. 4000. 5000. 6000. 7000. 8000. Barley. Oats. Radish. Rye. Triticale. Vetch. February planted. March planted. April planted. LSD.

  14. Effects of Moringa oleifera LAM, Leguminous Plants and NPK Fertilizer Comparatively on Orange Fleshed Sweet Potato in Alley Cropping System

    Directory of Open Access Journals (Sweden)

    IN Abdullahi

    2014-09-01

    Full Text Available The research work conducted at the Teaching and Research Farm of University of Abuja was aimed at assessing the effect of Moringa oleifera, selected leguminous plants and inorganic fertilizer on the performance of orange fleshed sweet potato in Alley Cropping System. Randomized Complete Block Design (RCBD using five treatments with three replications was applied. Data collected include: percentage survival of sweet potato, length per vine (cm, number of leaves per vine, leaf area of sweet potato, weed dry matter (g/m2, yield of sweet potato roots. Highest number of leaves (28 per plant was recorded in the control plot while the plots with NPK fertilizer had the highest length per vine (94.55cm though not significantly (p>0.05 different from others. Higher percent survival (88% of sweet potato was recorded from control plots. Stands grown in Arachis hypogeae plots produced the highest leaf area (0.202m2 while plots in which NPK fertilizer was applied experienced highest weed dry matter (4.083g/m2 although highest root yield (1.2t/ha was recorded from the plots with NPK fertilizer. DOI: http://dx.doi.org/10.3126/ije.v3i3.11061 International Journal of Environment Vol.3(3 2014: 24-35

  15. Application of the flour of four leguminous crops for the control of ...

    African Journals Online (AJOL)

    Provender used to breed animals is constituted mainly of cereal flour. However, due to poor post-harvest technologies, more than 35% of annual crop yield is often lost during storage as a consequence of insect attack. While synthetic insecticides constitute an efficient method for reducing these losses; current excessive ...

  16. Productivity and carbon dioxide exchange of the leguminous crops: Estimates from flux tower measurements

    Science.gov (United States)

    Net CO2 exchange data on legume crops at 17 flux tower sites in North America and 3 sites in Europe representing 29 site-years of measurements were partitioned into gross photosynthesis and ecosystem respiration using a light-response function method, resulting in new estimates of ecosystem-scale ec...

  17. 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.

  18. The potential of cover crops for improving soil function

    Science.gov (United States)

    Stoate, Chris; Crotty, Felicity

    2017-04-01

    Cover crops can be grown over the autumn and winter ensuring green cover throughout the year. They have been described as improving soil structure, reducing soil erosion and potentially even a form of grass weed control. These crops retain nutrients within the plant, potentially making them available for future crops, as well as increasing soil organic matter. Over the last three years, we have investigated how different cover crop regimes affect soil quality. Three separate experiments over each autumn/winter period have investigated how different cover crops affect soil biology, physics and chemistry, with each experiment building on the previous one. There have been significant effects of cover crops on soil structure, as well as significantly lower weed biomass and increased yields in the following crop - in comparison to bare stubble. For example, the effect of drilling the cover crops on soil structure in comparison to a bare stubble control that had not been driven on by machinery was quantified, and over the winter period the soil structure of the cover crop treatments changed, with compaction reduced in the cover crop treatments, whilst the bare stubble control remained unchanged. Weeds were found in significantly lower biomass in the cover crop mixes in comparison to the bare stubble control, and significantly lower weed biomass continued to be found in the following spring oat crop where the cover crops had been, indicating a weed suppressive effect that has a continued legacy in the following crop. The following spring oats have shown similar results in the last two years, with higher yields in the previous cover crop areas compared to the bare stubble controls. Overall, these results are indicating that cover crops have the potential to provide improvements to soil quality, reduce weeds and improve yields. We discuss the economic implications.

  19. Establishment and function of cover crops interseeded into corn

    Science.gov (United States)

    Cover crops can provide ecological services and improve the resiliency of annual cropping systems; however, cover crop use is low in corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotations in the upper Midwest due to challenges with establishment. Our objective was to compare three planting me...

  20. Plant growth promotion in cereal and leguminous agricultural important plants: from microorganism capacities to crop production.

    Science.gov (United States)

    Pérez-Montaño, F; Alías-Villegas, C; Bellogín, R A; del Cerro, P; Espuny, M R; Jiménez-Guerrero, I; López-Baena, F J; Ollero, F J; Cubo, T

    2014-01-01

    Plant growth-promoting rhizobacteria (PGPR) are free-living bacteria which actively colonize plant roots, exerting beneficial effects on plant development. The PGPR may (i) promote the plant growth either by using their own metabolism (solubilizing phosphates, producing hormones or fixing nitrogen) or directly affecting the plant metabolism (increasing the uptake of water and minerals), enhancing root development, increasing the enzymatic activity of the plant or "helping" other beneficial microorganisms to enhance their action on the plants; (ii) or may promote the plant growth by suppressing plant pathogens. These abilities are of great agriculture importance in terms of improving soil fertility and crop yield, thus reducing the negative impact of chemical fertilizers on the environment. The progress in the last decade in using PGPR in a variety of plants (maize, rice, wheat, soybean and bean) along with their mechanism of action are summarized and discussed here. Copyright © 2013 Elsevier GmbH. All rights reserved.

  1. Trifolium isthmocarpum Brot, a salt-tolerant wild leguminous forage crop in salt-affected soils

    Directory of Open Access Journals (Sweden)

    Kawtar Bennani

    2013-08-01

    Full Text Available Plant scientists are investigating the potential of previously unexploited legume species where environmental and biological stresses constrain the use of more conventional forage crops or where these species are better suited to the needs of sustainable agriculture. Trifolium isthmocarpum Brot., Moroccan clover, occurs as a weed in different habitats in Morocco. It grows in moderately saline areas, where traditional forage legumes cannot be cultivated; however, it has not been widely studied despite its good palatability. The salt tolerance was studied between natural field conditions and glasshouse. The extensive field studies have recorded the species in many different habitats ranging from healthy agricultural lands to abandoned saline areas. The plants maintained high nodulation capacity (ranging between 60% and 97% and nitrogenase activities (average 2.04 µmol C2H4 plant-1 h-1 in different habitats. Shoot systems of plants collected from salt-affected soils exhibited higher concentrations of Na+ and Cl- than those collected from healthy soils. Greenhouse experiments showed that germination percentage and vigor value of the studied species was not significantly (P > 0.05 affected at 160 mM NaCl, and that 25% of the germination ability was maintained when growing on substrats containing 240 mM NaCl. The growth rate of seedlings was not signicantly affected by 160 mM NaCl but was reduced by 38% under 240 mM NaCl. Leaf succulence and indices of leaf water status did not differ among the salt treatments, whereas relative water content was reduced by only 8% and water content at saturation increased by about 12% at high salt concentrations in the growing medium. This study suggest recommending the cultivation of T. isthmocarpum in salt-affected soils, which are widespread and pose a problem for the farmers of Morocco and other countries in the world’s arid belt.

  2. Linkages between land Cover, enzymes, and soil organic matter chemistry following encroachment of leguminous woody plant into grasslands

    Science.gov (United States)

    Filley, T. R.; Stott, D. E.; Boutton, T. W.; Creamer, C. A.; Olk, D.

    2009-12-01

    only weak trends with age when normalized to carbon content. Although, PPO was nearly invariant across the chronosequence, lignin content rose dramatically, normalized both to soil mass and to organic carbon content, indicating oxidase activity was not matched to input and lignin was selectively accruing in the below ground carbon pools. We propose that the dramatic increase in available N in the leguminous system suppressed microbial oxidase production allowing lignin to selectively accrue while microbial activity for the other plant biopolymers has nearly kept pace with input-consistent with recent findings in other temperate deciduous systems. These results have important implications for the modeling of woodland-grassland conversion and the dynamics of biogeochemical cycles in this globally significant land cover change.

  3. C and N accumulations in soil aggregates determine nitrous oxide emissions from cover crop treated rice paddy soils during fallow season

    Energy Technology Data Exchange (ETDEWEB)

    Pramanik, Prabhat, E-mail: prabhat2003@gmail.com; Haque, Md. Mozammel; Kim, Sang Yoon; Kim, Pil Joo, E-mail: pjkim@gnu.ac.kr

    2014-08-15

    Combination of leguminous and non-leguminous plant residues are preferably applied in rice paddy soils to increase the rate of organic matter mineralization and to improve plant growth. However, organic matter addition facilitates methane (CH{sub 4}) emission from rice paddy soil. Mineralization of organic nitrogen (N) increases NO{sub 3}–N concentrations in soil, which are precursors for the formation of nitrous oxide (N{sub 2}O). However, N{sub 2}O is a minor greenhouse gas emitted from submerged rice field and hence is not often considered during calculation of total global warming potential (GWP) during rice cultivation. The hypothesis of this study was that fluxes of N{sub 2}O emissions might be changed after removal of flooded water from rice field and the effect of cover crops on N{sub 2}O emissions in the fallow season might be interesting. However, the effects of N-rich plant residues on N{sub 2}O emission rates in the fallow season and its effect on annual GWP were not studied before. In this experiment, combination of barley (non-leguminous) and hairy vetch (leguminous) biomasses were applied at 9 Mg ha{sup −1} and 27 Mg ha{sup −1} rates in rice paddy soil. Cover crop application significantly increased CH{sub 4} emission flux while decreased N{sub 2}O emissions during rice cultivation. The lowest N{sub 2}O emission was observed in 27 Mg ha{sup −1} cover crop treated plots. Cover crop applications increased N contents in soil aggregates especially in smaller aggregates (< 250 μm), and that proportionately increased the N{sub 2}O emission potentials of these soil aggregates. Fluxes of N{sub 2}O emissions in the fallow season were influenced by the N{sub 2}O emission potentials of soil aggregates and followed opposite trends as those observed during rice cultivation. Therefore, it could be concluded that the doses of cover crop applications for rice cultivation should not be optimized considering only CH{sub 4}, but N{sub 2}O should also be

  4. Farmers' evaluation of legume cover crops for erosion control in ...

    African Journals Online (AJOL)

    Farmers' evaluation of legume cover crops for erosion control in Gathwariga catchment, Kenya. ... International Journal of Agriculture and Rural Development ... Studies were conducted in Gathwariga catchment, Kenya with the aim of evaluating farmers' perception about the impact of legume cover crops (LCC) on soil ...

  5. Cover crop-based ecological weed management: exploration and optimization

    NARCIS (Netherlands)

    Kruidhof, H.M.

    2008-01-01

    Keywords: organic farming, ecologically-based weed management, cover crops, green manure, allelopathy, Secale cereale, Brassica napus, Medicago sativa Cover crop-based ecological weed management: exploration and optimization. In organic farming systems, weed control is recognized as one of the

  6. Remote sensing to monitor cover crop adoption in southeastern Pennsylvania

    Science.gov (United States)

    Hively, Wells; Sjoerd Duiker,; Greg McCarty,; Prabhakara, Kusuma

    2015-01-01

    In the Chesapeake Bay Watershed, winter cereal cover crops are often planted in rotation with summer crops to reduce the loss of nutrients and sediment from agricultural systems. Cover crops can also improve soil health, control weeds and pests, supplement forage needs, and support resilient cropping systems. In southeastern Pennsylvania, cover crops can be successfully established following corn (Zea mays L.) silage harvest and are strongly promoted for use in this niche. They are also planted following corn grain, soybean (Glycine max L.), and vegetable harvest. In Pennsylvania, the use of winter cover crops for agricultural conservation has been supported through a combination of outreach, regulation, and incentives. On-farm implementation is thought to be increasing, but the actual extent of cover crops is not well quantified. Satellite imagery can be used to map green winter cover crop vegetation on agricultural fields and, when integrated with additional remote sensing data products, can be used to evaluate wintertime vegetative groundcover following specific summer crops. This study used Landsat and SPOT (System Probatoire d’ Observation de la Terre) satellite imagery, in combination with the USDA National Agricultural Statistics Service Cropland Data Layer, to evaluate the extent and amount of green wintertime vegetation on agricultural fields in four Pennsylvania counties (Berks, Lebanon, Lancaster, and York) from 2010 to 2013. In December of 2010, a windshield survey was conducted to collect baseline data on winter cover crop implementation, with particular focus on identifying corn harvested for silage (expected earlier harvest date and lower levels of crop residue), versus for grain (expected later harvest date and higher levels of crop residue). Satellite spectral indices were successfully used to detect both the amount of green vegetative groundcover and the amount of crop residue on the surveyed fields. Analysis of wintertime satellite imagery

  7. Short Communication A vetch winter cover crop can improve ...

    African Journals Online (AJOL)

    A high nitrogen (N) fertiliser requirement can be a deterrent to the adoption of conservation agriculture (CA). A field trial was carried out to test whether a high biomass-yielding vetch (Vicia dasycarpa L.) winter cover crop can be used to improve N response and profitability of a subsequent maize (Zea mays L.) crop under ...

  8. Cover Crops in West Africa: Contributing to Sustainable Agriculture ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    This book examines the potential for using cover crops to maintain and improve soil fertility in West Africa. It documents past experiences withcover cropping in Africa and will hopefully stimulate future research on priority socioeconomic and biophysical aspects of this important topic. The editors Daniel Buckles is Senior ...

  9. Effects of double cropped on yield and biomass accumulation of cover crops in Kansas

    OpenAIRE

    Roozeboom, K.; Mahama, G.Y.; Mengel, D.B.; Prasad, P.V. Vara

    2013-01-01

    Metadata only record The contribution of nitrogen (N) by cover crops is an important component of sustainable agriculture and alternative source of N. Legume summer and winter cover crops can decrease inorganic N fertilizer requirements and production costs through symbiotic N2 fixation. It is also vital to make maximum use of the available land during the growing season. However, summer crop yields may be decreased due to shortened length of growing season and risk of water shortage. The ...

  10. Estimating Crop Cover Fraction from Digital Color Images

    Science.gov (United States)

    Karakus, P.; Karabork, H.

    2017-11-01

    The use of automated methods to estimate crop cover fraction from digital color images has increased in recent years. Crop cover fraction can determine accurate, fast and inexpensive with this methods. A digital color images was acquired over each of the 30 sample fields in 2014 year at 2-3 week intervals. Study area has 15 sunflower fields and 15 corn fields. Digital color images were collected during 4 months, namely over the course of the growing season from sowing until harvesting to determine crop cover fraction. We used two approach to estimate crop cover fraction. In first method, the images were transformed from the RGB (red, green, blue) color space to the HSI (hue, intensity, saturation) color space. We used an object-based image analysis approach to classify the images into green vegetation and the other materials. In the second method, The Green Crop Tracker is less labor and time intensive than the object-based classification approach, is a viable alternative to ground-based methods. By comparing object-based classification method and Green Crop Tracker software 2014 growing season, results were obtained: There were high correlations between the estimations obtained by object-based classification method and Green Crop Tracker software (for 2014 R2 = 0.89). The relationship between two methods for 2014-23 sunflower field was calculated R2 = 0.97.

  11. Efficacy of Crop Cover in Controlling Viral Disease of Squash

    Directory of Open Access Journals (Sweden)

    A. Zouba

    1998-01-01

    Full Text Available The efficacy of using crop cover in controlling viral diseases of squash was studied under field conditions. Results of the study revealed that crop cover of 15 to 30 d delayed the onset of disease incidence, spread and severity of viral diseases, leading to improvement in vegetative growth and consequently, to increase and subsequent improvement in fruit yield and quality. It was observed that 21 d was the optional coverage period for higher fruit yield. Vegetative growth and fruit yield and quality did not differ significantly for plants under cover for IS d and 30 d.

  12. C and N accumulations in soil aggregates determine nitrous oxide emissions from cover crop treated rice paddy soils during fallow season.

    Science.gov (United States)

    Pramanik, Prabhat; Haque, Md Mozammel; Kim, Sang Yoon; Kim, Pil Joo

    2014-08-15

    Combination of leguminous and non-leguminous plant residues are preferably applied in rice paddy soils to increase the rate of organic matter mineralization and to improve plant growth. However, organic matter addition facilitates methane (CH4) emission from rice paddy soil. Mineralization of organic nitrogen (N) increases NO3-N concentrations in soil, which are precursors for the formation of nitrous oxide (N2O). However, N2O is a minor greenhouse gas emitted from submerged rice field and hence is not often considered during calculation of total global warming potential (GWP) during rice cultivation. The hypothesis of this study was that fluxes of N2O emissions might be changed after removal of flooded water from rice field and the effect of cover crops on N2O emissions in the fallow season might be interesting. However, the effects of N-rich plant residues on N2O emission rates in the fallow season and its effect on annual GWP were not studied before. In this experiment, combination of barley (non-leguminous) and hairy vetch (leguminous) biomasses were applied at 9 Mg ha(-1) and 27 Mg ha(-1) rates in rice paddy soil. Cover crop application significantly increased CH4 emission flux while decreased N2O emissions during rice cultivation. The lowest N2O emission was observed in 27 Mg ha(-1) cover crop treated plots. Cover crop applications increased N contents in soil aggregates especially in smaller aggregates (<250 μm), and that proportionately increased the N2O emission potentials of these soil aggregates. Fluxes of N2O emissions in the fallow season were influenced by the N2O emission potentials of soil aggregates and followed opposite trends as those observed during rice cultivation. Therefore, it could be concluded that the doses of cover crop applications for rice cultivation should not be optimized considering only CH4, but N2O should also be considered especially for fallow season to calculate total GWP. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. The Use of Cover Crops as Climate-Smart Management in Midwest Cropping Systems

    Science.gov (United States)

    Basche, A.; Miguez, F.; Archontoulis, S.; Kaspar, T.

    2014-12-01

    The observed trends in the Midwestern United States of increasing rainfall variability will likely continue into the future. Events such as individual days of heavy rain as well as seasons of floods and droughts have large impacts on agricultural productivity and the natural resource base that underpins it. Such events lead to increased soil erosion, decreased water quality and reduced corn and soybean yields. Winter cover crops offer the potential to buffer many of these impacts because they essentially double the time for a living plant to protect and improve the soil. However, at present, cover crops are infrequently utilized in the Midwest (representing 1-2% of row cropped land cover) in particular due to producer concerns over higher costs and management, limited time and winter growing conditions as well as the potential harm to corn yields. In order to expand their use, there is a need to quantify how cover crops impact Midwest cropping systems in the long term and namely to understand how to optimize the benefits of cover crops while minimizing their impacts on cash crops. We are working with APSIM, a cropping systems platform, to specifically quantify the long term future impacts of cover crop incorporation in corn-based cropping systems. In general, our regional analysis showed only minor changes to corn and soybean yields (Agriculture Project (CSCAP), a collaboration of eleven Midwestern institutions established to evaluate how conservation practices, including cover crops, improve the resilience of Midwest agriculture to future change. Such collaborations can help better quantify long term impacts of conservation practices on the landscape that ultimately lead to more climate-smart management of such agricultural systems.

  14. Assessing cover crop management under actual and climate change conditions.

    Science.gov (United States)

    Alonso-Ayuso, María; Quemada, Miguel; Vanclooster, Marnik; Ruiz-Ramos, Margarita; Rodriguez, Alfredo; Gabriel, José Luis

    2018-04-15

    The termination date is recognized as a key management factor to enhance cover crops for multiple benefits and to avoid competition with the following cash crop. However, the optimum date depends on annual meteorological conditions, and climate variability induces uncertainty in a decision that needs to be taken every year. One of the most important cover crop benefits is reducing nitrate leaching, a major concern for irrigated agricultural systems and highly affected by the termination date. This study aimed to determine the effects of cover crops and their termination date on the water and N balances of an irrigated Mediterranean agroecosystem under present and future climate conditions. For that purpose, two field experiments were used for inverse calibration and validation of the WAVE model (Water and Agrochemicals in the soil and Vadose Environment), based on continuous soil water content data, soil nitrogen content and crop measurements. The calibrated and validated model was subsequently used in advanced scenario analysis under present and climate change conditions. Under present conditions, a late termination date increased cover crop biomass and subsequently soil water and N depletion. Hence, preemptive competition risk with the main crop was enhanced, but a reduction of nitrate leaching also occurred. The hypothetical planting date of the following cash crop was also an important tool to reduce preemptive competition. Under climate change conditions, the simulations showed that the termination date will be even more important to reduce preemptive competition and nitrate leaching. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  15. Cover crops to improve soil health and pollinator habitat in nut orchards

    Science.gov (United States)

    Jerry. Van Sambeek

    2017-01-01

    Recently several national programs have been initiated calling for improving soil health and creating pollinator habitat using cover crops. Opportunities exist for nut growers to do both with the use of cover crops in our nut orchards. Because we can include perennial ground covers as cover crops, we have even more choices than landowners managing cover crops during...

  16. Effects of cover crops and weed management on corn yield

    Directory of Open Access Journals (Sweden)

    Farhood Yeganehpoor

    2015-06-01

    Full Text Available One of the most important replacement methods used instead of chemical herbicide and conventional tillage is cover and companion crops’ application which is a major factor in sustainable agriculture. In order to determine the best cover crop in controlling weeds of corn field and its further effects on corn yield, an experiment was carried out in a factorial arrangement based on RCB design with three replicates. The treatments of this experiment included companion crops (clover, hairy vetch, basil and dill as first factor and time of sowing cover and medicinal plant (synchronic sowing with corn and sowing 15 days after corn sowing as second factor. The results showed that ear weight, ear length, leaf weight, grain length and yield were significantly influenced by companion crops and sowing date. Whereas, weed biomass was influenced by cover crop type × sowing date interaction. Also, the results indicated that increasing biomass weed resulted in linear reduction of grain yield. The highest ear weight, ear length, leaf weight, grain length and yield were obtained for cultivation of clover with corn. Synchronic cultivation of companion crops with corn had higher grain length and yield compared with cultivation 15 days after corn. The lowest weed biomass was recorded for concurrent cultivation of corn with clover due to rapid growth and high competitive power of clover in the early stage of growth.

  17. Tillage and cover cropping effects on soil properties and crop production in Illinois

    Science.gov (United States)

    Cover crops (CCs) have been heralded for their potential to improve soil properties, retain nutrients in the field, and increase subsequent crop yields yet support for these claims within the state of Illinois remains limited. We assessed the effects of integrating five sets of CCs into a corn-soybe...

  18. Biomass and nutrient cycling by winter cover crops

    Directory of Open Access Journals (Sweden)

    Jana Koefender

    Full Text Available ABSTRACT Cover crops are of fundamental importance for the sustainability of the no-tillage system, to ensure soil coverage and to provide benefits for the subsequent crop. The objective of this study was to evaluate the production of biomass and the content and accumulation of nutrients by winter cover crops. The experimental design used in the experiment was a randomized complete block with four replications and six treatments: oilseed radish, vetch, black oats, vetch + black oats, vetch + oilseed radish and fallow. Black oat, oilseed radish in single cultivation and black oat + vetch and vetch + oilseed radish intercroppings showed higher dry matter production. Vetch + oilseed radish intercropping demonstrates higher performance regarding cycling of nutrients, with higher accumulations of N, P, K, Ca, Mg, S, Cu, Zn, Fe, Na and B.

  19. Evaluation of fallow and cover crops for nematode suppression in ...

    African Journals Online (AJOL)

    A study was conducted in three agroecological zones of south-western Nigeria to evaluate the effect of siam weed (Chromolaena odorata) and mucuna (Mucuna utilis) cover/fallow crops on plant-parasitic nematode population. The natural bush regrowth was used as control. Plant-parasitic nematodes were identified and ...

  20. Ipomea asarifolia (Desr), A Potential Cover Crop for Soil Fertility ...

    African Journals Online (AJOL)

    Danfodiyo University, Sokoto main campus, in the Sudan Savanna of Nigeria was investigated. The study determined the effect of the plant .... cover crop and develop large quantities of organic matter in the soils through their leaf .... soil through the shedding of leaf litter, decay of the roots, stems and other parts of the plant ...

  1. Feasibility of winter cover crop production under rainfed conditions ...

    African Journals Online (AJOL)

    Low winter rainfall poses a challenge to production of high biomass from cover crops, which is necessary for the success of conservation agriculture systems in the Eastern Cape Province of South Africa. An experiment was conducted to evaluate the adaptability of white oats (Avena sativa), grazing vetch (Vicia dasycarpa), ...

  2. Cover Crops Effects on Soil Chemical Properties and Onion Yield

    Directory of Open Access Journals (Sweden)

    Rodolfo Assis de Oliveira

    2016-01-01

    Full Text Available ABSTRACT Cover crops contribute to nutrient cycling and may improve soil chemical properties and, consequently, increase crop yield. The aim of this study was to evaluate cover crop residue decomposition and nutrient release, and the effects of these plants on soil chemical properties and on onion (Allium cepa L. yield in a no-tillage system. The experiment was carried out in an Inceptisol in southern Brazil, where cover crops were sown in April 2012 and 2013. In July 2013, shoots of weeds (WD, black oats (BO, rye (RY, oilseed radish (RD, oilseed radish + black oats (RD + BO, and oilseed radish + rye (RD + RY were cut at ground level and part of these material from each treatment was placed in litter bags. The litter bags were distributed on the soil surface and were collected at 0, 30, 45, 60, 75, and 90 days after distribution (DAD. The residues in the litter bags were dried, weighed, and ground, and then analyzed to quantify lignin, cellulose, non-structural biomass, total organic carbon (TOC, N, P, K, Ca, and Mg. In November 2012 and 2013, onion crops were harvested to quantify yield, and bulbs were classified according to diameter, and the number of rotted and flowering bulbs was determined. Soil in the 0.00-0.10 m layer was collected for chemical analysis before transplanting and after harvesting onion in December 2012 and 2013. The rye plant residues presented the highest half-life and they released less nutrients until 90 DAD. The great permanence of rye residue was considered a protection to soil surface, the opposite was observed with spontaneous vegetation. The cultivation and addition of dry residue of cover crops increased the onion yield at 2.5 Mg ha-1.

  3. Humic substances and its distribution in coffee crop under cover crops and weed control methods

    Directory of Open Access Journals (Sweden)

    Bruno Henrique Martins

    2016-08-01

    Full Text Available ABSTRACT Humic substances (HS comprise the passive element in soil organic matter (SOM, and represent one of the soil carbon pools which may be altered by different cover crops and weed control methods. This study aimed to assess HS distribution and characteristics in an experimental coffee crop area subjected to cover crops and cultural, mechanical, and chemical weed control. The study was carried out at Londrina, in the state of Paraná, southern Brazil (23°21’30” S; 51°10’17” W. In 2008, seven weed control/cover crops were established in a randomized block design between two coffee rows as the main-plot factor per plot and soil sampling depths (0-10 cm, 10-20 cm, 20-30 cm and 30-40 cm as a split-plot. HS were extracted through alkaline and acid solutions and analyzed by chromic acid wet oxidation and UV-Vis spectroscopy. Chemical attributes presented variations in the topsoil between the field conditions analyzed. Cover crop cutting and coffee tree pruning residues left on the soil surface may have interfered in nutrient cycling and the humification process. Data showed that humic substances comprised about 50 % of SOM. Although different cover crops and weed control methods did not alter humic and fulvic acid carbon content, a possible incidence of condensed aromatic structures at depth increments in fulvic acids was observed, leading to an average decrease of 53 % in the E4/E6 ratio. Humin carbon content increased 25 % in the topsoil, particularly under crop weed-control methods, probably due to high incorporation of recalcitrant structures from coffee tree pruning residues and cover crops.

  4. Cover crop frequency and compost effects on a legume-rye cover crop during 8 years of organic vegetables

    Science.gov (United States)

    Organic matter inputs from compost or cover crops (CC) are important to maintain or improve soil quality, but their impact in high-value vegetable production systems are not well understood. Therefore, we evaluated the effects of CC frequency (every winter versus every 4th winter) and yard-waste co...

  5. Aggregate distribution and associated organic carbon influenced by cover crops

    Science.gov (United States)

    Barquero, Irene; García-González, Irene; Benito, Marta; Gabriel, Jose Luis; Quemada, Miguel; Hontoria, Chiquinquirá

    2013-04-01

    Replacing fallow with cover crops during the non-cropping period seems to be a good alternative to diminish soil degradation by enhancing soil aggregation and increasing organic carbon. The aim of this study was to analyze the effect of replacing fallow by different winter cover crops (CC) on the aggregate distribution and C associated of an Haplic Calcisol. The study area was located in Central Spain, under semi-arid Mediterranean climate. A 4-year field trial was conducted using Barley (Hordeum vulgare L.) and Vetch (Vicia sativa L.) as CC during the intercropping period of maize (Zea mays L.) under irrigation. All treatments were equally irrigated and fertilized. Maize was directly sown over CC residues previously killed in early spring. Composite samples were collected at 0-5 and 5-20 cm depths in each treatment on autumn of 2010. Soil samples were separated by wet sieving into four aggregate-size classes: large macroaggregates ( >2000 µm); small macroaggregates (250-2000 µm); microaggregates (53-250 µm); and small macroaggregates > microaggregates > silt + clay size. Treatments did not influence C concentration in aggregate-size classes. In conclusion, cover crops improved soil structure increasing the proportion of macroaggregates and MWD being Barley more effective than Vetch at subsurface layer.

  6. Biological and microbiological attributes in Oxisol managed with cover crops

    Directory of Open Access Journals (Sweden)

    Rodrigo Ferreira da Silva

    2017-05-01

    Full Text Available The inclusion of winter cover crops and fertilization with nitrogen to the soil can have an effect on their biological and microbiological attributes. The aim of this study was to evaluate biological and microbiological attributes in soil under different winter cover crops and nitrogen doses. The experiment was conducted at the Frederico Westphalen-RS campus of the Federal University of Santa Maria (UFSM in a Rhodic Hapludox soil. The experimental design was a randomized block in factorial arrangement (2 x 10: 10 winter cover crops systems (Fallow [control], black oats, white oats, ryegrass, forage turnip, vetch, white lupine; black oat + forage turnip; black oat + vetch and black oat + vetch + fodder turnip, and two nitrogen rates in the form of urea applied in successive crops of beans common and maize, with four replications. We assessed the biological attributes (Margalef’s richness, Simpson’s dominance, Shannon’s diversity and abundance of organisms and microbiological (carbon and nitrogen microbial biomass, basal respiration, metabolic quotient and microbial quotient of the soil. The fallow with wild species and white lupine showed greater Simpson’s dominance and abundance of organisms due to the increase in the number of individuals of the order Collembola. Vetch improved the biological attributes of the soil with increase in Collembola abundance and diversity of organisms of soil fauna. The application of nitrogen favored the microbial biomass carbon and reduced the metabolic quotient.

  7. Tillage System and Cover Crop Effects on Soil Quality

    DEFF Research Database (Denmark)

    Abdollahi, Lotfollah; Munkholm, Lars Juhl

    2014-01-01

    , penetration resistance, and visual evaluation of soil structure (VESS). In the laboratory, aggregate strength, water-stable aggregates (WSA), and clay dispersibility were measured. The analyzed chemical and biological properties included soil organic C (SOC), total N, microbial biomass C, labile P and K...... benefit of using a combination of cover crops and direct drilling to produce a better soil friability. The usefulness of the VESS method for soil structural evaluation was supported by the high positive correlation of MWD with VESS scores.......Optimal use of management systems including tillage and winter cover crops is recommended to improve soil quality and sustain agricultural production. The effects on soil properties of three tillage systems (as main plot) including direct drilling (D), harrowing to a depth of 8 to 10 cm (H...

  8. Cover crop effect on subsequent wheat yield and water use efficiency in the central great plains

    Science.gov (United States)

    Crop production systems in the water-limited environment of the semi-arid central Great Plains may not have potential to profitably use cover crops because of lowered subsequent wheat (Triticum asestivum L.) yields following the cover crop. Cover crop mixtures have reportedly shown less yield-reduci...

  9. Manipulating cover crops to increase mycorrhizal colonization in corn (Zea mays)

    Science.gov (United States)

    Field studies were performed to determine the influence of cover crop treatments on the abundance of mycorrhizal fungi which can increase nutrient uptake by cash crops. Replicated plots established in spring wheat were assigned to eight cover crop treatments: No cover crop, winter canola, oats, hai...

  10. 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......) 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......, but the effect was insignificant. The effect of tillage and previous N rates were also insignificant but the present use of cover crops had a small but significant decreasing effect on leaching compared to no cover cropping. The cover crop was well established in both years but grew less vigorously during autumn...

  11. Nitrogen Fertilizer Source, Rates, and Timing for a Cover Crop and Subsequent Cotton Crop

    Science.gov (United States)

    The objectives were to compare N fertilizer sources, rates, and time of application for a rye winter cover crop to determine optimal biomass production for conservation tillage production, compare recommended and no additional N fertilizer rates across different biomass levels for cotton, and determ...

  12. Cover crop and nitrogen fertilization influence soil carbon and nitrogen under bioenergy sweet sorghum

    Science.gov (United States)

    Cover crop and N fertilization may maintain soil C and N levels under sweet sorghum (Sorghum bicolor [L.] Moench) biomass harvested for bioenergy production. The effect of cover crops (hairy vetch [Vicia villosa Roth], rye [Secaele cereale L.], hairy vetch/rye mixture, and the control [no cover crop...

  13. Cover crops in mixtures do not use water differently than single-species plantings

    Science.gov (United States)

    Some recent statements have been made about the benefits of growing cover crops in mixtures as compared with single-species plantings of cover crops. One of those stated benefits is greatly reduced water use by cover crops grown in mixtures. The objectives of this study were to characterize soil wat...

  14. Tillage System and Cover Crop Effects on Soil Quality

    DEFF Research Database (Denmark)

    Abdollahi, Lotfollah; Munkholm, Lars Juhl

    2014-01-01

    in the spring of 2012 before cultivation. Soil water retention and air permeability were measured for matric potentials ranging from −1 to −30 kPa. Gas diffusivity was measured at −10 kPa. Computed tomography (CT) scanning was also used to characterize soil pore characteristics. At the 4- to 8- and 18- to 27-cm...... depths, pore characteristics did not differ significantly among tillage treatments. At the 12- to 16-cm depth, negative effects of reduced tillage (D and H) were recorded for total porosity and air-filled porosity at −10 kPa (that is, >30-μm pores). Generally, the use of a cover crop increased air......-filled porosity at −10 kPa, air permeability, and pore organization and reduced the value of blocked air porosity at all depths for all tillage treatments. Our results show that the cover crop created continuous macropores and in this way improved the conditions for water and gas transport and root growth...

  15. Molecular, Genetic and Agronomic Approaches to Utilizing Pulses as Cover Crops and Green Manure into Cropping Systems.

    Science.gov (United States)

    Tani, Eleni; Abraham, Eleni; Chachalis, Demosthenis; Travlos, Ilias

    2017-06-05

    Cover crops constitute one of the most promising agronomic practices towards a more sustainable agriculture. Their beneficial effects on main crops, soil and environment are many and various, while risks and disadvantages may also appear. Several legumes show a high potential but further research is required in order to suggest the optimal legume cover crops for each case in terms of their productivity and ability to suppress weeds. The additional cost associated with cover crops should also be addressed and in this context the use of grain legumes such as cowpea, faba bean and pea could be of high interest. Some of the aspects of these grain legumes as far as their use as cover crops, their genetic diversity and their breeding using conventional and molecular approaches are discussed in the present review. The specific species seem to have a high potential for use as cover crops, especially if their noticeable genetic diversity is exploited and their breeding focuses on several desirable traits.

  16. Nitrous oxide emissions from soils amended by cover-crops and under plastic film mulching: Fluxes, emission factors and yield-scaled emissions

    Science.gov (United States)

    Kim, Gil Won; Das, Suvendu; Hwang, Hyun Young; Kim, Pil Joo

    2017-03-01

    Assessment of nitrous oxide (N2O) emission factor (EF) for N2O emission inventory from arable crops fertilized with different nitrogen sources are under increased scrutiny because of discrepancies between the default IPCC EFs and low EFs reported by many researchers. Mixing ratio of leguminous and non-leguminous cover crop residues incorporation and plastic film mulching (PFM) in upland soil has been recommended as a vital agronomic practice to enhance yield and soil quality. However, how these practices together affect N2O emissions, yield-scaled emissions and the EFs remain uncertain. Field experiments spanning two consecutive years were conducted to evaluate the effects of PFM on N2O emissions, yield-scaled emissions and the seasonal EFs in cover crop residues amended soil during maize cultivation. The mixture of barley (Hordeum vulgare) and hairy vetch (Vicia villosa) seeds with 75% recommended dose (RD 140 kg ha-1) and 25% recommended dose (RD 90 kg ha-1), respectively, were broadcasted during the fallow period and 0, 25, 50 and 100% of the total aboveground harvested biomass that correspond to 0, 76, 152 and 304 kg N ha-1 were incorporated before maize transplanting. It was found that the mean seasonal EFs from cover crop residues amended soil under No-mulching (NM) and PFM were 1.13% (ranging from 0.81 to 1.23%) and 1.49% (ranging from 1.02 to 1.63%), respectively, which are comparable to the IPCC (2006) default EF (1%) for emission inventories of N2O from crop residues. The emission fluxes were greatly influenced by NH4+sbnd N, NO3--N, DOC and DON contents of soil. The cumulative N2O emissions markedly increased with the increase in cover crop residues application rates and it was more prominent under PFM than under NM. However, the yield-scaled emissions markedly decreased under PFM compared to NM due to the improved yield. With relatively low yield-scaled N2O emissions, 25% biomass mixing ratio of barley and hairy vetch (76 kg N ha-1) under PFM could be

  17. 7 CFR 1437.504 - Notice of loss for covered tropical crops.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Notice of loss for covered tropical crops. 1437.504... CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS NONINSURED CROP DISASTER... crops. (a) The provisions of § 1437.10(c) regarding late filed notice of loss do not apply to covered...

  18. Disease risks associated with cover crops in corn and soybean production

    Science.gov (United States)

    Cover crops have numerous environmental and soil health benefits and are being more widely used by farmers in Iowa. Still some farmers are reluctant to use cover crops because of increased risks to crop yields in part because of increased disease potential. The goal of our research is to understand ...

  19. Timing of glyphosate applications to wheat cover crops to reduce onion stunting caused by Rhizoctonia solani

    Science.gov (United States)

    Stunting caused by Rhizoctonia spp. is economically important in irrigated onion bulb crops in the semi-arid Columbia Basin of Oregon and Washington, where cereal winter cover crops commonly are planted the previous fall to prevent wind erosion of soil. The cover crop is killed with herbicide applic...

  20. Management of Overwintering Cover Crops Influences Floral Resources and Visitation by Native Bees.

    Science.gov (United States)

    Ellis, Katherine E; Barbercheck, Mary E

    2015-08-01

    The incorporation of cover crops into annual crop rotations is one practice that is used in the Mid-Atlantic United States to manage soil fertility, suppress weeds, and control erosion. Additionally, flowering cover crops have the potential to support beneficial insect communities, such as native bees. Because of the current declines in managed honey bee colonies, the conservation of native bee communities is critical to maintaining "free" pollination services. However, native bees are negatively affected by agricultural intensification and are also in decline across North America. We conducted two experiments to assess the potential of flowering cover crops to act as a conservation resource for native bees. We evaluated the effects of cover crop diversity and fall planting date on floral resource availability and visitation by native bees for overwintering flowering cover crop species commonly used in the Mid-Atlantic region. Cover crop species, crop rotation schedule, and plant diversity significantly influenced floral resource availability. Different cover crop species not only had different blooming phenologies and winter survival responses to planting date, but attracted unique bee communities. Flower density was the primary factor influencing frequency of bee visitation across cover crop diversity and fall planting date treatments. The results from these experiments will be useful for informing recommendations on the applied use of flowering cover crops for pollinator conservation purposes. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. SOIL CHEMICAL ATTRIBUTES AND LEAF NUTRIENTS OF ‘PACOVAN’ BANANA UNDER TWO COVER CROPS

    Directory of Open Access Journals (Sweden)

    JOSÉ EGÍDIO FLORI

    2016-01-01

    Full Text Available Banana is one of the most consumed fruits in the world, which is grown in most tropical countries. The objective of this work was to evaluate the main attributes of soil fertility in a banana crop under two cover crops and two root development locations. The work was conducted in Curaçá, BA, Brazil, between October 2011 and May 2013, using a randomized block design in split plot with five repetitions. Two cover crops were assessed in the plots, the cover 1 consisting of Pueraria phaseoloides, and the cover 2 consisting of a crop mix with Sorghum bicolor, Ricinus communis L., Canavalia ensiformis, Mucuna aterrima and Zea mays, and two soil sampling locations in the subplots, between plants in the banana rows (location 1 and between the banana rows (location 2. There were significant and independent effects for the cover crop and sampling location factors for the variables organic matter, Ca and P, and significant effects for the interaction between cover crops and sampling locations for the variables potassium, magnesium and total exchangeable bases. The cover crop mix and the between-row location presented the highest organic matter content. Potassium was the nutrient with the highest negative variation from the initial content and its leaf content was below the reference value, however not reducing the crop yield. The banana crop associated with crop cover using the crop mix provided greater availability of nutrients in the soil compared to the coverage with tropical kudzu.

  2. Cover crops do not increase C sequestration in production crops: evidence from 12 years of continuous measurements

    Science.gov (United States)

    Buysse, Pauline; Bodson, Bernard; Debacq, Alain; De Ligne, Anne; Heinesch, Bernard; Manise, Tanguy; Moureaux, Christine; Aubinet, Marc

    2017-04-01

    The numerous reports on carbon (C) loss from cropland soils have recently raised awareness on the climate change mitigation potential of these ecosystems, and on the necessity to improve C sequestration in these soils. Among the multiple solutions that are proposed, several field measurement and modelling studies reported that growing cover crops over fall and winter time could appear as an efficient solution. However, while the large majority of these studies are based on SOC stock inventories and very few information exists from the CO2 flux dynamics perspective. In the present work, we use the results from long-term (12 years) eddy-covariance measurements performed at the Lonzée Terrestrial Observatory (LTO, candidate ICOS site, Belgium) and focus on six intercrop periods managed with (3) and without (3) cover crops after winter wheat main crops, in order to compare their response to environmental factors and to investigate the impact of cover crops on Net Ecosystem Exchange (NEE). Our results showed that cumulated NEE was not significantly affected by the presence of cover crops. Indeed, while larger CO2 assimilation occurred during cover crop growth, this carbon gain was later lost by larger respiration rates due to larger crop residue amounts brought to the soil. As modelled by a Q10-like relationship, significantly larger R10 values were indeed observed during the three intercrop periods cultivated with cover crops. These CO2 flux-based results therefore tend to moderate the generally acknowledged positive impact of cover crops on net C sequestration by croplands. Our results indicate that the effect of growing cover crops on C sequestration could be less important than announced, at least at certain sites.

  3. Post harvest fertility status of some cotton based leguminous and non-leguminous intercropping systems

    International Nuclear Information System (INIS)

    Khan, M.B.; Khaliq, A.

    2003-01-01

    Residual effect of different leguminous and non-leguminous intercropping systems on cotton planted in two planting patterns was studied at Agronomic Research Area, Univ. of Agriculture, Faisalabad under irrigated conditions of Central Punjab. Soil samples were collected from 0-15 cm and 15-30 cm depths before planting and after harvesting of each crop, each year to evaluate the impact of leguminous and non-leguminous crops included in this study. Experiment was laid out in randomized complete block design (R.C.B.D.) with split arrangement and four replications. Patterns were randomized in main plots and intercrops in sub plots. Plot size was 4.8 m x 7 m. All the intercrops produced substantially smaller yields when grown in association with cotton in either planting pattern compared to their sole crop yields. Residual nitrogen was improved in leguminous intercropping systems as compared to cotton alone as well non-legume intercropping systems. Similarly organic matter was also improved in all intercropping treatments, and maximum increase was recorded due to cowpeas. Phosphorus was depleted in all intercropping systems during both years under study as well as in relation to cotton alone. The same trend (depletion) was also observed in case of residual soil Potassium.(author)

  4. Cover crops to improve soil health and pollinator habitat in nut orchards: Part II

    Science.gov (United States)

    Jerry. Van Sambeek

    2017-01-01

    Integrating cover crops into a nut orchard can have some unique benefits and problems not found when used cover crops during the fallow period between cash crops. Studies show ground covers can reduce hardwood tree growth anywhere from a few percent to more than 70 percent in the case of tall fescue. This means if it takes 3 years to put on one inch of diameter growth...

  5. Winter cover crops on processing tomato yield, quality, pest pressure, nitrogen availability, and profit margins.

    Science.gov (United States)

    Belfry, Kimberly D; Trueman, Cheryl; Vyn, Richard J; Loewen, Steven A; Van Eerd, Laura L

    2017-01-01

    Much of cover crop research to date focuses on key indicators of impact without considering the implications over multiple years, in the absence of a systems-based approach. To evaluate the effect of three years of autumn cover crops on subsequent processing tomato (Solanum lycopersicum L.) production in 2010 and 2011, a field split-split-plot factorial design trial with effects of cover crop type, urea ammonium nitrate fertilizer rate (0 or 140 kg N ha-1 preplant broadcast incorporated) and tomato cultivar (early vs. late) was conducted. The main plot factor, cover crop, included a no cover crop control, oat (Avena sativa L.), winter cereal rye (hereafter referred to as rye) (Secale cereale L.), oilseed radish (OSR) (Raphanus sativus L. var. oleiferus Metzg Stokes), and mix of OSR and rye (OSR + rye) treatments. Cover crop biomass of 0.5 to 2.8 and 1.7 to 3.1 Mg ha-1 was attained in early Oct. and the following early May, respectively. In general, OSR increased soil mineral N during cover crop growth and into the succeeding summer tomato growing season, while the remaining cover crops did not differ from the no cover crop control. The lack of a cover crop by N rate interaction in soil and plant N analyses at harvest suggests that growers may not need to modify N fertilizer rates to tomatoes based on cover crop type. Processing tomato fruit quality at harvest (rots, insect or disease damage, Agtron colour, pH, or natural tomato soluble solids (NTSS)) was not affected by cover crop type. In both years, marketable yield in the no cover crop treatment was lower or not statistically different than all planted cover crops. Partial profit margins over both years were 1320 $ ha-1 higher with OSR and $960 higher with oat compared to the no cover crop control. Thus, results from a systems-based approach suggest that the cover crops tested had no observed negative impact on processing tomato production and have the potential to increase marketable yield and profit margins.

  6. Winter cover crops on processing tomato yield, quality, pest pressure, nitrogen availability, and profit margins.

    Directory of Open Access Journals (Sweden)

    Kimberly D Belfry

    Full Text Available Much of cover crop research to date focuses on key indicators of impact without considering the implications over multiple years, in the absence of a systems-based approach. To evaluate the effect of three years of autumn cover crops on subsequent processing tomato (Solanum lycopersicum L. production in 2010 and 2011, a field split-split-plot factorial design trial with effects of cover crop type, urea ammonium nitrate fertilizer rate (0 or 140 kg N ha-1 preplant broadcast incorporated and tomato cultivar (early vs. late was conducted. The main plot factor, cover crop, included a no cover crop control, oat (Avena sativa L., winter cereal rye (hereafter referred to as rye (Secale cereale L., oilseed radish (OSR (Raphanus sativus L. var. oleiferus Metzg Stokes, and mix of OSR and rye (OSR + rye treatments. Cover crop biomass of 0.5 to 2.8 and 1.7 to 3.1 Mg ha-1 was attained in early Oct. and the following early May, respectively. In general, OSR increased soil mineral N during cover crop growth and into the succeeding summer tomato growing season, while the remaining cover crops did not differ from the no cover crop control. The lack of a cover crop by N rate interaction in soil and plant N analyses at harvest suggests that growers may not need to modify N fertilizer rates to tomatoes based on cover crop type. Processing tomato fruit quality at harvest (rots, insect or disease damage, Agtron colour, pH, or natural tomato soluble solids (NTSS was not affected by cover crop type. In both years, marketable yield in the no cover crop treatment was lower or not statistically different than all planted cover crops. Partial profit margins over both years were 1320 $ ha-1 higher with OSR and $960 higher with oat compared to the no cover crop control. Thus, results from a systems-based approach suggest that the cover crops tested had no observed negative impact on processing tomato production and have the potential to increase marketable yield and profit

  7. Cover crop root, shoot, and rhizodeposit contributions to soil carbon in a no- till corn bioenergy cropping system

    Science.gov (United States)

    Austin, E.; Grandy, S.; Wickings, K.; McDaniel, M. D.; Robertson, P.

    2016-12-01

    Crop residues are potential biofuel feedstocks, but residue removal may result in reduced soil carbon (C). The inclusion of a cover crop in a corn bioenergy system could provide additional biomass and as well as help to mitigate the negative effects of residue removal by adding belowground C to stable soil C pools. In a no-till continuous corn bioenergy system in the northern portion of the US corn belt, we used 13CO2 pulse labeling to trace C in a winter rye (secale cereale) cover crop into different soil C pools for two years following rye termination. Corn stover contributed 66 (another 163 was in harvested corn stover), corn roots 57, rye shoot 61, rye roots 59, and rye rhizodeposits 27 g C m-2 to soil C. Five months following cover crop termination, belowground cover crop inputs were three times more likely to remain in soil C pools and much of the root-derived C was in mineral- associated soil fractions. Our results underscore the importance of cover crop roots vs. shoots as a source of soil C. Belowground C inputs from winter cover crops could substantially offset short term stover removal in this system.

  8. Cover Crop Species and Management Influence Predatory Arthropods and Predation in an Organically Managed, Reduced-Tillage Cropping System.

    Science.gov (United States)

    Rivers, Ariel N; Mullen, Christina A; Barbercheck, Mary E

    2018-01-29

    Agricultural practices affect arthropod communities and, therefore, have the potential to influence the activities of arthropods. We evaluated the effect of cover crop species and termination timing on the activity of ground-dwelling predatory arthropods in a corn-soybean-wheat rotation in transition to organic production in Pennsylvania, United States. We compared two cover crop treatments: 1) hairy vetch (Vicia villosa Roth) planted together with triticale (×Triticosecale Wittmack) after wheat harvest, and 2) cereal rye (Secale cereale Linnaeus) planted after corn harvest. We terminated the cover crops in the spring with a roller-crimper on three dates (early, middle, and late) based on cover crop phenology and standard practices for cash crop planting in our area. We characterized the ground-dwelling arthropod community using pitfall traps and assessed relative predation using sentinel assays with live greater waxworm larvae (Galleria mellonella Fabricius). The activity density of predatory arthropods was significantly higher in the hairy vetch and triticale treatments than in cereal rye treatments. Hairy vetch and triticale favored the predator groups Araneae, Opiliones, Staphylinidae, and Carabidae. Specific taxa were associated with cover crop condition (e.g., live or dead) and termination dates. Certain variables were positively or negatively associated with the relative predation on sentinel prey, depending on cover crop treatment and stage, including the presence of predatory arthropods and various habitat measurements. Our results suggest that management of a cover crop by roller-crimper at specific times in the growing season affects predator activity density and community composition. Terminating cover crops with a roller-crimper can conserve generalist predators.

  9. Summer cover crops and soil amendments to improve growth and nutrient uptake of okra

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Q.R.; Li, Y.C.; Klassen, W. [University of Florida, Homestead, FL (United States). Center for Tropical Research & Education

    2006-04-15

    A pot experiment with summer cover crops and soil amendments was conducted in two consecutive years to elucidate the effects of these cover crops and soil amendments on 'Clemson Spineless 80' okra (Abelmoschus esculentus) yields and biomass production, and the uptake and distribution of soil nutrients and trace elements. The cover crops were sunn hemp (Crotalaria juncea), cowpea (Vigna unguiculata), velvetbean (Mucuna deeringiana), and sorghum sudan-grass (Sorghum bicolor x S. bicolor var. sudanense) with fallow as the control. The organic soil amendments were biosolids (sediment from wastewater plants), N-Viro Soil (a mixture of biosolids and coal ash), coal ash (a combustion by-product from power plants), co-compost (a mixture of 3 biosolids: 7 yard waste), and yard waste compost (mainly from leaves and branches of trees and shrubs, and grass clippings) with a soil-incorporated cover crop as the control. As a subsequent vegetable crop, okra was grown after the cover crops, alone or together with the organic soil amendments, had been incorporated. All of the cover crops, except sorghum sudangrass in 2002-03, significantly improved okra fruit yields and the total biomass production. Both cover crops and soil amendments can substantially improve nutrient uptake and distribution. The results suggest that cover crops and appropriate amounts of soil amendments can be used to improve soil fertility and okra yield without adverse environmental effects or risk of contamination of the fruit. Further field studies will be required to confirm these findings.

  10. Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model

    Science.gov (United States)

    Yeo, In-Young; Lee, Sangchui; Sadeghi, Ali M.; Beeson, Peter C.; Hively, W. Dean; McCarty, Greg W.; Lang, Megan W.

    2013-01-01

    Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay Watershed (CBW), which is located in the Mid-Atlantic US, winter cover crop use has been emphasized and federal and state cost-share programs are available to farmers to subsidize the cost of winter cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops at the watershed scale and to identify critical source areas of high nitrate export. A physically-based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data and satellite-based estimates of winter cover crop species performance to simulate hydrological processes and nutrient cycling over the period of 1991–2000. Multiple scenarios were developed to obtain baseline information on nitrate loading without winter cover crops planted and to investigate how nitrate loading could change with different winter cover crop planting scenarios, including different species, planting times, and implementation areas. The results indicate that winter cover crops had a negligible impact on water budget, but significantly reduced nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading was approximately 14 kg ha−1, but it decreased to 4.6–10.1 kg ha−1 with winter cover crops resulting in a reduction rate of 27–67% at the watershed scale. Rye was most effective, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of winter cover crops (~30 days of additional growing days) was crucial, as it lowered nitrate export by an additional ~2 kg ha−1 when compared to late planting scenarios. The effectiveness of cover cropping increased with increasing extent of winter cover crop implementation. Agricultural fields with well-drained soils

  11. Evaluation of Cowpea Germplasm Lines Adapted for Use as a Cover Crop in the Southeastern US

    Science.gov (United States)

    Cowpeas (Vigna unguiculata) are desirable as a cover crop, because they are tolerant of heat, drought and poor soils, grow vigorously and compete well against weeds, and provide nitrogen for rotational crops. Cowpeas were grown extensively as a forage and green manure crop in the southeastern U.S. ...

  12. Ruminant Grazing of Cover Crops: Effects on Soil Properties and Agricultural Production

    Science.gov (United States)

    Poffenbarger, Hanna

    2010-01-01

    Integrating livestock into a cropping system by allowing ruminant animals to graze cover crops may yield economic and environmental benefits. The effects of grazing on soil physical properties, soil organic matter, nitrogen cycling and agricultural production are presented in this literature review. The review found that grazing cover crops…

  13. US-1136, US-1137, and US-1138 Cowpea Germplasm Lines for Use as a Cover Crop

    Science.gov (United States)

    The adoption of sustainable and organic cultural practices in recent years has resulted in an increased use of cover crops. Cowpea (Vigna unguiculata L.) is an excellent warm season cover crop due to its tolerance of heat and drought stress, ability to grow well in sandy, poor, acidic soils, high b...

  14. A comparison of drill and broadcast methods for establishing cover crops on beds

    Science.gov (United States)

    Cover crops stands that are sufficiently dense soon after planting are more likely to suppress weeds, scavenge nutrients, and reduce erosion. Small-scale organic vegetable farmers often use broadcasting methods to establish cover crops but lack information on the most effective tool to incorporate ...

  15. An early-killed rye cover crop has potential for weed management in edamame

    Science.gov (United States)

    The potential role of fall-seeded cover crops for weed management in edamame is unknown. Field experiments were conducted over three edamame growing seasons to test the following objectives: 1) determine the extent to which cover crop residue management systems influence edamame emergence while sele...

  16. Principles and practices of using cover crops in weed management systems

    OpenAIRE

    Teasdale, J.

    2003-01-01

    Metadata only record Cover crops are plant species that are introduced into crop rotations to provide beneficial services to the agro-ecosystem. Some of the most important environmental services provided by cover crops include soil protection from erosion, capture and prevention of soil nutrient losses, fixation of nitrogen by legumes, increase in soil carbon and associated improvements in soil physical and chemical characteristics, decrease in soil temperature, increase in biological dive...

  17. Use of crop canopy cover to estimate lettuce Etc in a greenhouse

    OpenAIRE

    Shahidian, Shakib; Serrano, João; Vieira, Fabiana; Coelho, Renato

    2014-01-01

    FAO PM Reference evapotranspiration, as described by Allen et al. (1998) is used extensively to calculate crop water needs, in the form of Crop evapotranspiration, ETc. The main challenge to its everyday use is the estimation of the correct crop coefficient (Kc). Although this can be done using crop growth stages, the farmer is left with a lot of guesswork. The objective of this work was to estimate the possibility of using canopy cover (Cc) measured by a standard camera to establish th...

  18. Single season effects of mixed-species cover crops on tomato health (cultivar Celebrity) in multi-state field trials

    Science.gov (United States)

    Cover crop use can help mitigate the deleterious effects of common cropping practices (e.g., tillage) and is, therefore, an important component of soil health maintenance. While known to be beneficial in the long term, the short-term effects of cover crops, specifically mixed-species cover crops in ...

  19. Ecological weed management by cover cropping : effects on weed growth in autumn and weed establishment in spring

    NARCIS (Netherlands)

    Kruidhof, H.M.; Bastiaans, L.; Kropff, M.J.

    2008-01-01

    Cover crops grown in the period between two main crops have potential as an important component of a system-oriented ecological weed management strategy. In late summer and autumn, the cover crop can suppress growth and seed production of weeds, whereas the incorporation of cover crop residues in

  20. Satellite Estimation of Fractional Cover in Several California Specialty Crops

    Science.gov (United States)

    Johnson, Lee; Cahn, Michael; Rosevelt, Carolyn; Guzman, Alberto; Farrara, Barry; Melton, Forrest S.

    2016-01-01

    Past research in California and elsewhere has revealed strong relationships between satellite NDVI, photosynthetically active vegetation fraction (Fc), and crop evapotranspiration (ETc). Estimation of ETc can support efficiency of irrigation practice, which enhances water security and may mitigate nitrate leaching. The U.C. Cooperative Extension previously developed the CropManage (CM) web application for evaluation of crop water requirement and irrigation scheduling for several high-value specialty crops. CM currently uses empirical equations to predict daily Fc as a function of crop type, planting date and expected harvest date. The Fc prediction is transformed to fraction of reference ET and combined with reference data from the California Irrigation Management Information System to estimate daily ETc. In the current study, atmospherically-corrected Landsat NDVI data were compared with in-situ Fc estimates on several crops in the Salinas Valley during 2011-2014. The satellite data were observed on day of ground collection or were linearly interpolated across no more than an 8-day revisit period. Results will be presented for lettuce, spinach, celery, broccoli, cauliflower, cabbage, peppers, and strawberry. An application programming interface (API) allows CM and other clients to automatically retrieve NDVI and associated data from NASA's Satellite Irrigation Management Support (SIMS) web service. The SIMS API allows for queries both by individual points or user-defined polygons, and provides data for individual days or annual timeseries. Updates to the CM web app will convert these NDVI data to Fc on a crop-specific basis. The satellite observations are expected to play a support role in Salinas Valley, and may eventually serve as a primary data source as CM is extended to crop systems or regions where Fc is less predictable.

  1. Limited Impact of a Fall-Seeded, Spring-Terminated Rye Cover Crop on Beneficial Arthropods.

    Science.gov (United States)

    Dunbar, Mike W; Gassmann, Aaron J; O'Neal, Matthew E

    2017-04-01

    Cover crops are beneficial to agroecosystems because they decrease soil erosion and nutrient loss while increasing within-field plant diversity. Greater plant diversity within cropping systems can positively affect beneficial arthropod communities. We hypothesized that increasing plant diversity within annually rotated corn and soybean with the addition of a rye cover crop would positively affect the beneficial ground and canopy-dwelling communities compared with rotated corn and soybean grown without a cover crop. From 2011 through 2013, arthropod communities were measured at two locations in Iowa four times throughout each growing season. Pitfall traps were used to sample ground-dwelling arthropods within the corn and soybean plots and sweep nets were used to measure the beneficial arthropods in soybean canopies. Beneficial arthropods captured were identified to either class, order, or family. In both corn and soybean, community composition and total community activity density and abundance did not differ between plots that included the rye cover crop and plots without the rye cover crop. Most taxa did not significantly respond to the presence of the rye cover crop when analyzed individually, with the exceptions of Carabidae and Gryllidae sampled from soybean pitfall traps. Activity density of Carabidae was significantly greater in soybean plots that included a rye cover crop, while activity density of Gryllidae was significantly reduced in plots with the rye cover crop. Although a rye cover crop may be agronomically beneficial, there may be only limited effects on beneficial arthropods when added within an annual rotation of corn and soybean. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Climate response to Amazon forest replacement by heterogeneous crop cover

    Science.gov (United States)

    Badger, A. M.; Dirmeyer, P. A.

    2015-11-01

    Previous modeling studies with atmospheric general circulation models and basic land surface schemes to balance energy and water budgets have shown that by removing the natural vegetation over the Amazon, the region's climate becomes warmer and drier. In this study we use a fully coupled Earth system model and replace tropical forests by a distribution of six common tropical crops with variable planting dates, physiological parameters and irrigation. There is still general agreement with previous studies as areal averages show a warmer (+1.4 K) and drier (-0.35 mm day-1) climate. Using an interactive crop model with a realistic crop distribution shows that regions of vegetation change experience different responses dependent upon the initial tree coverage and whether the replacement vegetation is irrigated, with seasonal changes synchronized to the cropping season. Areas with initial tree coverage greater than 80 % show an increase in coupling with the atmosphere after deforestation, suggesting land use change could heighten sensitivity to climate anomalies, while irrigation acts to dampen coupling with the atmosphere.

  3. Cover crop residue management for optimizing weed control

    NARCIS (Netherlands)

    Kruidhof, H.M.; Bastiaans, L.; Kropff, M.J.

    2009-01-01

    Although residue management seems a key factor in residue-mediated weed suppression, very few studies have systematically compared the influence of different residue management strategies on the establishment of crop and weed species. We evaluated the effect of several methods of pre-treatment and

  4. 6 Rotation of Maize with some Leguminous Food

    African Journals Online (AJOL)

    Administrator

    Of the various management practices, which can increase the productivity of crops, fertilizer application normally gives the highest returns (Chowdhury & Chetty, 1979). For maize production, NARP/CSIR (1998). Rotation of Maize with some Leguminous Food Crops for. Sustainable Production on the Vertisols of the Accra ...

  5. Nitrate Leaching from Winter Cereal Cover Crops Using Undisturbed Soil-Column Lysimeters.

    Science.gov (United States)

    Meisinger, John J; Ricigliano, Kristin A

    2017-05-01

    Cover crops are important management practices for reducing nitrogen (N) leaching, especially in the Chesapeake Bay watershed, which is under total maximum daily load (TMDL) restraints. Winter cereals are common cool-season crops in the Bay watershed, but studies have not directly compared nitrate-N (NO-N) leaching losses from these species. A 3-yr cover crop lysimeter study was conducted in Beltsville, MD, to directly compare NO-N leaching from a commonly grown cultivar of barley ( L.), rye ( L.), and wheat ( L.), along with a no-cover control, using eight tension-drained undisturbed soil column lysimeters in a completely randomized design with two replicates. The lysimeters were configured to exclude runoff and to estimate NO-N leaching and flow-weighted NO-N concentration (FWNC). The temporal pattern of NO-N leaching showed a consistent highly significant ( < 0.001) effect of lower NO-N leaching with cover crops compared with no cover but showed only small and periodically significant ( < 0.05) effects among the cultivars of barley, rye, and wheat covers. Nitrate-N leaching was more affected by the quantity of establishment-season (mid-October to mid-December) precipitation than by cover crop species. For example, compared with no cover, winter cereal covers reduced NO-N leaching 95% in a dry year and 50% in wet years, with corresponding reductions in FWNC of 92 and 43%, respectively. These results are important for scientists, nutrient managers, and policymakers because they directly compare NO-N leaching from winter cereal covers and expand knowledge for developing management practices for winter cereals that can improve water quality and increase N efficiency in cropping systems. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  6. Effects of cover crops on the nitrogen fluxes in a silage maize production system

    NARCIS (Netherlands)

    Schröder, J.J.; Dijk, van W.; Groot, de W.J.M.

    1996-01-01

    Rye and grass cover crops can potentially intercept residual soil mineral nitrogen (SMN), reduce overwinter leaching, transfer SMN to next growing seasons and reduce the fertilizer need of subsequent crops. These aspects were studied for 6 years in continuous silage maize cv. LG 2080 production

  7. Increasing diveristy of arbuscular mycorrhizal fungi in agroecosystems using specific cover crops

    Science.gov (United States)

    Fall-planted cover crops provide a plant host for obligate symbiotic arbuscular mycorrhizal fungi (AMF) during otherwise fallow periods and thus may increase AMF numbers in agroecosystems. Increased AMF numbers should increase mycorrhizal colonization of the subsequent cash crops, which has been li...

  8. Winter cover crop seeding rate and variety effects during eight years of organic vegetables: III. Cover crop residue quality and nitrogen mineralization

    Science.gov (United States)

    Winter cover crops (CC) can improve nutrient-use efficiency in tillage-intensive systems. Shoot residue quality and soil mineral N following incorporation of rye (Secale cereale L.), legume-rye, and mustard CC was determined in December to February or March during the first 8 yr of the Salinas Orga...

  9. Cover cropping under temperate conditions: influence of growth period and incorporation time

    DEFF Research Database (Denmark)

    Thomsen, Ingrid Kaag; Hansen, Elly Møller

    Cover crops (CC) are generally followed by spring sown crops which limits the use of winter cereals in a crop rotation. A change from winter cereals as e.g. winter wheat (Triticum aestivum L.) to a spring sown crop as barley (Hordeum vulgare L.) often results in a reduction in grain yield....... To encourage increased use of CC and to lessen the consequences on choice of main crop new innovative ways of using CC should be considered. This study tested the potential for using CC that could allow for repeated winter wheat growing and still permit CC in breaks between crops. Cruciferous CC (Raphanus...... sativus L., Sinapis alba L.) spread in a growing winter wheat crop in July and incorporated in September (Autumn CC) before sowing the following winter wheat was compared with the same CC cultivars sown after harvest and incorporated in spring (Winter CC). The cruciferous CC were compared with Winter CC...

  10. Flowering cover crops in winter increase pest control but not trophic link diversity

    OpenAIRE

    Damien , Maxime; Le Lann , Cécile; Desneux , Nicolas; Alford , Lucy; Al Hassan , Diab; Georges , Romain; Van Baaren , Joan

    2017-01-01

    International audience; In agrosystems, the increase in non-crop plant diversity by habitat management in or around arable fields contributes to improved Conservation Biological Control. During winter, plant flower are often used as monospecific ground cover and are expected to die before flowering as a result of recurrent frost events. Decreases in minimal temperature due to climate change offers new possibilities for plants used in such sown cover crops to mature and flowers. Changes in pla...

  11. Comparison of Mechanical and Chemical Winter Cereal Cover Crop Termination Systems and Cotton Yield in Conservation Agriculture

    Science.gov (United States)

    An integral component of conservation agriculture systems in cotton is the use of a high-residue winter cover crop; however, terminating such cover crops is a cost and planting into high-residue is a challenge. Black oat, rye, and wheat winter cover crops were flattened with a straight-blade mechan...

  12. Alleyway Cover Crops have Little Influence on Pinot Noir Grapevines (Vitis vinifera L.) in Two Western Oregon Vineyards

    Science.gov (United States)

    Seven cover crop treatments were compared in two north Willamette Valley ‘Pinot noir’ vineyards over two years to test if alleyway cover crops that are mowed in spring and summer compete with grapevines for water or nutrients. Five different cover crop mixtures (planted in the fall of 2003) were com...

  13. EFFECT OF COVER CROPS ON SOIL ATTRIBUTES, PLANT NUTRITION, AND IRRIGATED TROPICAL RICE YIELD

    Directory of Open Access Journals (Sweden)

    ANDRE FROES DE BORJA REIS

    2017-01-01

    Full Text Available In flood plains, cover crops are able to alter soil properties and significantly affect rice nutrition and yield. The aims of this study were to determine soil properties, plant nutrition, and yield of tropical rice cultivated on flood plains after cover crop cultivation with conventional tillage (CT and no-tillage system (NTS at low and high nitrogen (N fertilization levels. The experimental design was a randomized block in a split-split-plot scheme with four replications. In the main plots were cover crops sunhemp (Crotalaria juncea and C. spectabilis, velvet bean (Mucuna aterrima, jackbean (Canavalia ensiformis, pigeon pea (Cajanus cajan, Japanese radish (Raphanus sativus, cowpea (Vigna unguiculata and a fallow field. In the subplots were the tillage systems (CT or NTS. The nitrogen fertilization levels in the sub-subplots were (10 kg N ha-1 and 45 kg N ha-1. All cover crops except Japanese radish significantly increased mineral soil nitrogen and nitrate concentrations. Sunhemp, velvet bean, and cowpea significantly increased soil ammonium content. The NTS provides higher mineral nitrogen and ammonium content than that by CT. Overall, cover crops provided higher levels of nutrients to rice plants in NTS than in CT. Cover crops provide greater yield than fallow treatments. Rice yield was higher in NTS than in CT, and greater at a higher rather than lower nitrogen fertilization level.

  14. Influence of cover crop treatments on the performance of a vineyard in a humid region

    Energy Technology Data Exchange (ETDEWEB)

    Trigo-Córdoba, E.; Bouzas-Cid, Y.; Orriols-Fernández, I.; Díaz-Losada, E.; Mirás-Avalos, J.M.

    2015-07-01

    Vineyards are usually managed by tilling the inter-rows to avoid competition from other plants for soil water and nutrients. However, in humid and sub-humid climates, such as that of NW Spain, cover crops may be an advantage for controlling vine vegetative growth and improving berry composition, while reducing management costs. The current study was conducted over three consecutive growing seasons (2012-2014) to assess the effects of establishing three permanent cover crop treatments on water relations, vine physiology, yield and berry composition of a vineyard of the red cultivar ‘Mencía’ (Vitis vinifera L.) located in Leiro, Ourense. Treatments consisted of four different soil management systems: ST, soil tillage; NV, native vegetation; ER, English ryegrass (Lolium perenne L.); and SC, subterranean clover (Trifolium subterraneum L.). Midday stem water potential was more negative in the native vegetation treatment, causing significant reductions in leaf stomatal conductance on certain dates. Total vine leaf area and pruning weight was reduced in the cover crop treatments in the last year of the experiment. Yield was unaffected by the presence of a cover crop. No significant differences among treatments were observed for berry composition; however, wines were positively affected by the SC treatment (higher tannin content and colour intensity and lower malic acid concentration when compared with ST). Wines from the cover crop treatments were preferred by taste panelists. These results indicate that in humid climates cover crop treatments can be useful for reducing vine vegetative growth without compromising yield and berry quality. (Author)

  15. Influence of cover crops on citrus crops on arbuscular mycorrhizal fungi development in the Colombian piedmont Oxisols

    Directory of Open Access Journals (Sweden)

    Hernán Javier Monroy L.

    2013-01-01

    Full Text Available Native arbuscular mycorrhizal fungi associated with grassand legume cover crops established on Oxisol soils in the Colombian piedmont (Meta were identified morphologically and the ability to colonize was evaluated. The experimental area consisted of cover crops Arachispintoi (CIAT 18744, Brachiaria brizantha cv. Toledo, B. dictyoneura cv. Llanero, Desmodium ovalifolium c v. Maquenque, Panicum maximum (CIAT 36000, Paspalumnotatum, and a chemical control (Glyphosate and mechanical control established in the rows in a Valencia orange grove. The experiment followed a complete randomized block design (8 cover crops and three replications, evaluated during the wet and dry seasons. Rhizosphere soil and grass and legumes roots were sampled in order to identified AMF and quantify the number of spores and the percentage of colonization. A total of 26 species were identified, including Acaulosporascrobiculata, A. morrowiae and, Scutellospora heterogama, which accounted for over 65% of the population. Thepercentage of root colonization ranged between 47% and 94% with spore counts between 63 and 300/100 g of dry soil. Cover crops with the highest colonization percentage and AMF diversity were B. brizantha, B. dictyoneura and P. notatumin their respective order. Glyphosate and mechanical control had a negative influence on the sporulation and colonization of the arbuscular mycorrhizal fungi in the root system

  16. The effect of different tillage and cover crops on soil quality

    DEFF Research Database (Denmark)

    Abdollahi, Lotfollah; Munkholm, Lars Juhl

    (direct drilling (D), harrowing (H) to a depth of 8 cm and ploughing to a depth of 20 cm (P)) as main plot. The soil was cropped with cover crop (+CC) or left without cover crop (-CC) as split plot treatments in the main plots with different tillage treatments. We assessed topsoil structural quality......This paper examines the effect of different tillage treatments and cover crop on soil physical, chemical and biological properties of a sandy loam soil in a long-term field trial set up in 2007 at Foulum, Denmark. The experimental design is a split plot design with different tillage practices...... in field using a visual method, measured unsaturated hydraulic conductivity at -4 hPa in field and determined aggregate size distribution after a drop shatter test for soil taken from 10-20 cm depth. The drop shatter test data showed significantly lowest mean weight diameter (MWD) for P than for H and D...

  17. Monitoring cover crops using radar remote sensing in southern Ontario, Canada

    Science.gov (United States)

    Shang, J.; Huang, X.; Liu, J.; Wang, J.

    2016-12-01

    Information on agricultural land surface conditions is important for developing best land management practices to maintain the overall health of the fields. The climate condition supports one harvest per year for the majority of the field crops in Canada, with a relative short growing season between May and September. During the non-growing-season months (October to the following April), many fields are traditionally left bare. In more recent year, there has been an increased interest in planting cover crops. Benefits of cover crops include boosting soil organic matters, preventing soil from erosion, retaining soil moisture, and reducing surface runoff hence protecting water quality. Optical remote sensing technology has been exploited for monitoring cover crops. However limitations inherent to optical sensors such as cloud interference and signal saturation (when leaf area index is above 2.5) impeded its operational application. Radar remote sensing on the other hand is not hindered by unfavorable weather conditions, and the signal continues to be sensitive to crop growth beyond the saturation point of optical sensors. It offers a viable means for capturing timely information on field surface conditions (with or without crop cover) or crop development status. This research investigated the potential of using multi-temporal RADARSAT-2 C-band synthetic aperture radar (SAR) data collected in 2015 over multiple fields of winter wheat, corn and soybean crops in southern Ontario, Canada, to retrieve information on the presence of cover crops and their growth status. Encouraging results have been obtained. This presentation will report the methodology developed and the results obtained.

  18. Winter Cover Crop Effects on Nitrate Leaching in Subsurface Drainage as Simulated by RZWQM-DSSAT

    Science.gov (United States)

    Malone, R. W.; Chu, X.; Ma, L.; Li, L.; Kaspar, T.; Jaynes, D.; Saseendran, S. A.; Thorp, K.; Yu, Q.

    2007-12-01

    Planting winter cover crops such as winter rye (Secale cereale L.) after corn and soybean harvest is one of the more promising practices to reduce nitrate loss to streams from tile drainage systems without negatively affecting production. Because availability of replicated tile-drained field data is limited and because use of cover crops to reduce nitrate loss has only been tested over a few years with limited environmental and management conditions, estimating the impacts of cover crops under the range of expected conditions is difficult. If properly tested against observed data, models can objectively estimate the relative effects of different weather conditions and agronomic practices (e.g., various N fertilizer application rates in conjunction with winter cover crops). In this study, an optimized winter wheat cover crop growth component was integrated into the calibrated RZWQM-DSSAT hybrid model and then we compare the observed and simulated effects of a winter cover crop on nitrate leaching losses in subsurface drainage water for a corn-soybean rotation with N fertilizer application rates over 225 kg N ha-1 in corn years. Annual observed and simulated flow-weighted average nitrate concentration (FWANC) in drainage from 2002 to 2005 for the cover crop treatments (CC) were 8.7 and 9.3 mg L-1 compared to 21.3 and 18.2 mg L-1 for no cover crop (CON). The resulting observed and simulated FWANC reductions due to CC were 59% and 49%. Simulations with the optimized model at various N fertilizer rates resulted in average annual drainage N loss differences between CC and CON to increase exponentially from 12 to 34 kg N ha-1 for rates of 11 to 261 kg N ha-1. The results suggest that RZWQM-DSSAT is a promising tool to estimate the relative effects of a winter crop under different conditions on nitrate loss in tile drains and that a winter cover crop can effectively reduce nitrate losses over a range of N fertilizer levels.

  19. Evaluation of cover crop and reduced cultivation for reducing nitrate leaching in Ireland.

    Science.gov (United States)

    Hooker, K V; Coxon, C E; Hackett, R; Kirwan, L E; O'Keeffe, E; Richards, K G

    2008-01-01

    Nitrate (NO(3)) loss from arable systems to surface and groundwater has attracted considerable attention in recent years in Ireland. Little information exists under Irish conditions, which are wet and temperate, on the effects of winter cover crops and different tillage techniques on NO(3) leaching. This study investigated the efficacy of such practices in reducing NO(3) leaching from a spring barley (Hordeum vulgare L.) system in the Barrow River valley, southeast Ireland. The study compared the effect of two tillage systems (plow-based tillage and noninversion tillage) and two over-winter alternatives (no vegetative cover and a mustard cover crop) on soil solution NO(3) concentrations at 90 cm depth over two winter drainage seasons (2003/04 and 2004/05). Soil samples were taken and analyzed for inorganic N. During both years of the study, the use of a mustard cover crop significantly reduced NO(3) losses for the plowed and reduced cultivation treatments. Mean soil solution NO(3) concentrations were between 38 and 70% lower when a cover crop was used, and total N load lost over the winter was between 18 and 83% lower. Results from this study highlight the importance of drainage volume and winter temperatures on NO(3) concentrations in soil solution and overall N load lost. It is suggested that cover crops will be of particular value in reducing NO(3) loss in temperate regions with mild winters, where winter N mineralization is important and high winter temperatures favor a long growing season.

  20. Cover crops and pruning in Bobal and Tempranillo vineyards have little influence on grapevine nutrition

    Directory of Open Access Journals (Sweden)

    Pedro Pérez-Bermúdez

    2016-06-01

    Full Text Available ABSTRACT Cover crops may improve vineyard soil properties, grapevine nutrient status and berry composition, however, factors such as cover crop type, annual rainfall, climate and irrigation may change their effects on vineyards. From 2008 to 2011, the effects of a non-permanent cover crop and two pruning techniques on soil as well as vine nutrients and grapevine performance of two vineyards (cv. Tempranillo and cv. Bobal were evaluated. For that purpose, two legumes were sown in inter-rows of hand-pruned vines in February and were tilled at flowering. Soil tillage, or cover cropping, was combined with either light pruning or severe pruning to study foliar nutrient variations. Soil N, P, K and total organic carbon (TOC were determined in samples taken from the Ap1 horizon in January prior to vine pruning. Foliar N, P, K contents were measured in leaves sampled upon grape veraison. The differences between vineyards with cover cropping and bare soils suggest that legumes positively affected soil N (1.55 vs. 1.68 g kg−1 and 1.49 vs. 1.76 g kg−1 in Bobal and Tempranillo vineyards, respectively and soil organic matter (SOM (12.5 vs. 15.5 g kg−1 and 12.9 vs. 17.2 g kg−1 in Bobal and Tempranillo vineyards, respectively. The use of cover crops did not affect grapevine yields nor quality of Bobal and Tempranillo berry . Cover crops, or light pruning, did not alter the foliar N, P, K contents of both cultivars since their concentrations were similar to those found in the leaves from vineyards with soil tillage or severe pruning.

  1. Effects of grain-producing cover crops on rice grain yield in Cabo Delgado, Mozambique

    Directory of Open Access Journals (Sweden)

    Adriano Stephan Nascente

    Full Text Available ABSTRACT Besides providing benefits to the environment such as soil protection, release of nutrients, soil moisture maintenance, and weed control, cover crops can increase food production for grain production. The aim of this study was to evaluate the production of biomass and grain cover crops (and its respective effects on soil chemical and physical attributes, yield components, and grain yield of rice in Mozambique. The study was conducted in two sites located in the province of Cabo Delgado, in Mozambique. The experimental design was a randomized block in a 2 × 6 factorial, with four repetitions. Treatments were carried out in two locations (Cuaia and Nambaua with six cover crops: Millet (Pennisetum glaucum L.; namarra bean (Lablab purpureus (L. Sweet, velvet beans (Mucuna pruriens L., oloco beans (Vigna radiata (L. R. Wilczek, cowpea (Vigna unguiculata L., and fallow. Cover crops provided similar changes in chemical and physical properties of the soil. Lablab purpureus, Vigna unguiculata, and Mucuna pruriens produced the highest dry matter biomass. Vigna unguiculada produced the highest amount of grains. Rice grain yields were similar under all cover crops and higher in Cuaia than Nambaua.

  2. PRACT (Prototyping Rotation and Association with Cover crop and no Till) - a tool for designing conservation agriculture systems

    NARCIS (Netherlands)

    Naudin, K.; Husson, M.O.; Scopel, E.; Auzoux, S.; Giller, K.E.

    2015-01-01

    Moving to more agroecological cropping systems implies deep changes in the organization of cropping systems. We propose a method for formalizing the process of innovating cropping system prototype design using a tool called PRACT (Prototyping Rotation and Association with Cover crop and no Till)

  3. Spectral Indices to Improve Crop Residue Cover Estimation under Varying Moisture Conditions

    Directory of Open Access Journals (Sweden)

    Miguel Quemada

    2016-08-01

    Full Text Available Crop residues on the soil surface protect the soil against erosion, increase water infiltration and reduce agrochemicals in runoff water. Crop residues and soils are spectrally different in the absorption features associated with cellulose and lignin. Our objectives were to: (1 assess the impact of water on the spectral indices for estimating crop residue cover (fR; (2 evaluate spectral water indices for estimating the relative water content (RWC of crop residues and soils; and (3 propose methods that mitigate the uncertainty caused by variable moisture conditions on estimates of fR. Reflectance spectra of diverse crops and soils were acquired in the laboratory over the 400–2400-nm wavelength region. Using the laboratory data, a linear mixture model simulated the reflectance of scenes with various fR and levels of RWC. Additional reflectance spectra were acquired over agricultural fields with a wide range of crop residue covers and scene moisture conditions. Spectral indices for estimating crop residue cover that were evaluated in this study included the Normalized Difference Tillage Index (NDTI, the Shortwave Infrared Normalized Difference Residue Index (SINDRI and the Cellulose Absorption Index (CAI. Multivariate linear models that used pairs of spectral indices—one for RWC and one for fR—significantly improved estimates of fR using CAI and SINDRI. For NDTI to reliably assess fR, scene RWC should be relatively dry (RWC < 0.25. These techniques provide the tools needed to monitor the spatial and temporal changes in crop residue cover and help determine where additional conservation practices may be required.

  4. Development and characterization of genic SSR markers in Medicago truncatula and their transferability in leguminous and non-leguminous species.

    Science.gov (United States)

    Gupta, Sarika; Prasad, Manoj

    2009-09-01

    Expressed sequence tag (EST)-derived simple sequence repeat (eSSR) markers are important resources for gene discovery and comparative mapping aimed at crop improvement. In this study, we developed eSSR markers for Medicago truncatula and assessed their cross-species transferability. We detected 36,847 non-redundant sequences ("unigenes") from 198,642 M. truncatula EST sequences. Mining of microsatellites from the 36,847 unigene sequences (representing approximately 25.8 Mb) revealed 14,637 eSSRs in 11,750 SSR-containing ESTs, and primer pairs were successfully designed for 4,636 (39.5%). Of the 14 637 eSSRs, 82.6% were mononucleotide repeats and the rest (in descending order of abundance) were tri-, di-, penta-, and tetranucleotide repeats. When less stringent SSR detection criteria were used, the frequency of dinucleotide repeat motifs increased more than twofold, and the frequencies of di- (11%) and trinucleotide motifs (10.6%) were almost equal. This demonstrates that the eSSR frequency and distribution were related to the choice of search criteria. Forty-one randomly selected primer pairs were validated, and their transferability in three leguminous and three non-leguminous species was assessed. The markers showed a high level of transferability in the leguminous (53%-71%) and non-leguminous (33%-44%) species. The validation studies thus demonstrate the utility of the Medicago eSSRs in assessing genomic relationships in both leguminous and non-leguminous species.

  5. Effect of Winter Cover Crops on Soil Nitrogen Availability, Corn Yield, and Nitrate Leaching

    Directory of Open Access Journals (Sweden)

    S. Kuo

    2001-01-01

    Full Text Available Biculture of nonlegumes and legumes could serve as cover crops for increasing main crop yield, while reducing NO3 leaching. This study, conducted from 1994 to 1999, determined the effect of monocultured cereal rye (Secale cereale L., annual ryegrass (Lolium multiflorum, and hairy vetch (Vicia villosa, and bicultured rye/vetch and ryegrass/vetch on N availability in soil, corn (Zea mays L. yield, and NO3-N leaching in a silt loam soil. The field had been in corn and cover crop rotation since 1987. In addition to the cover crop treatments, there were four N fertilizer rates (0, 67, 134, and 201 kg N ha-1, referred to as N0, N1, N2, and N3, respectively applied to corn. The experiment was a randomized split-block design with three replications for each treatment. Lysimeters were installed in 1987 at 0.75 m below the soil surface for leachate collection for the N0, N2, and N3 treatments. The result showed that vetch monoculture had the most influence on soil N availability and corn yield, followed by the bicultures. Rye or ryegrass monoculture had either no effect or an adverse effect on corn yield and soil N availability. Leachate NO3-N concentration was highest where vetch cover crop was planted regardless of N rates, which suggests that N mineralization of vetch N continued well into the fall and winter. Leachate NO3-N concentration increased with increasing N fertilizer rates and exceeded the U.S. Environmental Protection Agency’s drinking water standard of 10 mg N l�1 even at recommended N rate for corn in this region (coastal Pacific Northwest. In comparisons of the average NO3-N concentration during the period of high N leaching, monocultured rye and ryegrass or bicultured rye/vetch and ryegrass/vetch very effectively decreased N leaching in 1998 with dry fall weather. The amount of N available for leaching (determined based on the presidedress nitrate test, the amount of N fertilizer applied, and N uptake correlated well with average NO3

  6. Salt and N leaching and soil accumulation due to cover cropping practices

    Science.gov (United States)

    Gabriel, J. L.; Quemada, M.

    2012-04-01

    Nitrate leaching beyond the root zone can increase water contamination hazards and decrease crop available N. Cover crops used in spite of fallow are an alternative to reduce nitrate contamination in the vadose zone, because reducing drainage and soil mineral N accumulation. Cover crops can improve important characteristics in irrigated land as water retention capacity or soil aggregate stability. However, increasing evapotranspiration and consequent drainage below the root system reduction, could lead to soil salt accumulation. Salinity affects more than 80 million ha of arable land in many areas of the world, and one of the principal causes for yield reduction and even land degradation in the Mediterranean region. Few studies dealt with both problems at the same time. Therefore, it is necessary a long-term evaluation of the potential effect on soil salinity and nitrate leaching, in order to ensure that potential disadvantages that could originate from soil salt accumulation are compensated with all advantages of cover cropping. A study of the soil salinity and nitrate leaching was conducted during 4 years in a semiarid irrigated agricultural area of Central Spain. Three treatments were studied during the intercropping period of maize (Zea mays L.): barley (Hordeum vulgare L.), vetch (Vicia villosa L.) and fallow. Cover crops were killed in March allowing seeding of maize of the entire trial in April, and all treatments were irrigated and fertilised following the same procedure. Before sowing, and after harvesting maize and cover crops, soil salt and nitrate accumulation was determined along the soil profile. Soil analysis was conducted at six depths every 0.20 m in each plot in samples from four 0 to 1.2-m depth holes dug. The electrical conductivity of the saturated paste extract and soil mineral nitrogen was measured in each soil sample. A numerical model based on the Richards water balance equation was applied in order to calculate drainage at 1.2 m depth

  7. Effect of winter cover crops on soil nitrogen availability, corn yield, and nitrate leaching.

    Science.gov (United States)

    Kuo, S; Huang, B; Bembenek, R

    2001-10-25

    Biculture of nonlegumes and legumes could serve as cover crops for increasing main crop yield, while reducing NO3 leaching. This study, conducted from 1994 to 1999, determined the effect of monocultured cereal rye (Secale cereale L.), annual ryegrass (Lolium multiflorum), and hairy vetch (Vicia villosa), and bicultured rye/vetch and ryegrass/vetch on N availability in soil, corn (Zea mays L.) yield, and NO3-N leaching in a silt loam soil. The field had been in corn and cover crop rotation since 1987. In addition to the cover crop treatments, there were four N fertilizer rates (0, 67, 134, and 201 kg N ha(-1), referred to as N0, N1, N2, and N3, respectively) applied to corn. The experiment was a randomized split-block design with three replications for each treatment. Lysimeters were installed in 1987 at 0.75 m below the soil surface for leachate collection for the N 0, N 2, and N 3 treatments. The result showed that vetch monoculture had the most influence on soil N availability and corn yield, followed by the bicultures. Rye or ryegrass monoculture had either no effect or an adverse effect on corn yield and soil N availability. Leachate NO3-N concentration was highest where vetch cover crop was planted regardless of N rates, which suggests that N mineralization of vetch N continued well into the fall and winter. Leachate NO3-N concentration increased with increasing N fertilizer rates and exceeded the U.S. Environmental Protection Agency's drinking water standard of 10 mg N l(-1) even at recommended N rate for corn in this region (coastal Pacific Northwest). In comparisons of the average NO3-N concentration during the period of high N leaching, monocultured rye and ryegrass or bicultured rye/vetch and ryegrass/vetch very effectively decreased N leaching in 1998 with dry fall weather. The amount of N available for leaching (determined based on the presidedress nitrate test, the amount of N fertilizer applied, and N uptake) correlated well with average NO3-N during

  8. Returning Winter Cover Crop Residue Influences Soil Aggregation and Humic Substances under Double-cropped Rice Fields

    Directory of Open Access Journals (Sweden)

    Haiming Tang

    2017-11-01

    Full Text Available ABSTRACT Residue management in cropping systems may improve soil quality. However, there are few studies on the effects of residue management on soil aggregation and carbon content in the humin (C-HUM, humic acid (C-HAF and fulvic acid (C-FAF fractions in South China. Therefore, the effects on soil aggregation and on the C-HUM, C-HAF, C-FAF from incorporating winter cover crop residues in a double-cropped rice (Oryza sativa L. system in South China fields were studied. The experiment has been conducted since winter 2004. Five winter cropping systems were used: rice-rice-ryegrass (Ry-R-R, rice-rice-Chinese milk vetch (Mv-R-R, rice-rice-potato (Po-R-R, rice-rice-rape (Ra-R-R and rice-rice with winter fallow (Fa-R-R. The results indicated that the organic C content in the paddy soil under the Ry-R-R, Mv-R-R, Po-R-R, and Ra-R-R systems was significantly higher than the content in the Fa-R-R system at the early rice and late rice maturity stages. The different sizes of aggregates under the five treatments showed similar trends. The Po-R-R systems had the highest percentage of soil aggregates in each size class and the Fa-R-R systems had the lowest percentage of soil aggregates in each size class in the 0.00-0.05, 0.05-0.10, and 0.10-0.20 m soil depth at the early rice and late rice maturity stages. The C-HUM, C-HAF, and C-FAF increased through long-term application of winter cover crop residues. Statistical analysis showed that the C-HAF under the Ra-R-R systems was significantly higher than that in the Fa-R-R systems at the early rice and late rice maturity stages. The C-FAF and C-HUM under the Mv-R-R systems was significantly higher than the C-FAF and C-HUM in the Fa-R-R systems at the early rice and late rice maturity stages. As a result, the soil organic C content, the soil aggregates in each size class, and the C-HUM, C-HAF, and C-FAF increased from application of winter cover crop residues in double-cropped rice systems.

  9. Utilization of residual nitrogen (15N) from cover crop and urea by corn

    International Nuclear Information System (INIS)

    Silva, Edson Cabral da; Muraoka, Takashi; Trivelin, Paulo Cesar Ocheuze; Buzetti, Salatier; Veloso, Marcos Emanuel da Costa

    2006-01-01

    The majority of N from mineral fertilizers and cover crops is usually not used by the very next corn crop, but can be absorbed by follow-up crops. The objective of this study was to evaluate the use of residual nitrogen from urea, sunnhemp (Crotalaria juncea) and millet (Pennisetum americanum) labeled with 15 N, applied to no-tillage corn in the previous growing season, in a Red Latosol of the Cerrado. The study was conducted in an experimental farm of the Sao Paulo State University (UNESP), Ilha Solteira, in Selviria county (MS), Brazil, in different areas. The experiment had a randomized complete block design, with 15 treatments and four replications. Treatments were applied to corn crop in the 2001/02 and 2003/04 growing seasons. They were distributed in a 3 x 5 factorial layout, representing the combination of three cover crops: sunnhemp, millet and spontaneous vegetation (fallow) and five N rates (as urea): 0, 30, 80, 130, and 180 kg ha-1 of N. After corn harvest, the two areas were followed in the dry season and were followed by corn crop in the 2002/03 (experiment 1) and 2003/04 (experiment 2) growing seasons, using the same fertilizer rate on all plots to distinguish the residual effect of N sources. The average use of residual N from the millet and sunnhemp residues (above-ground part) by corn crop was less than 3.5 and 3 %, respectively, of the initial amount. The corn uptake of residual N from urea increased in a quadratic manner in experiment 1 and linearly in experiment Two as a response to the applied N rates, and the recover was below 3 %. The cover crop type did not affect the use of residual N of urea by corn, and vice-versa. (author)

  10. Cover crops effect on farm benefits and nitrate leaching: linking economic and environmental analysis

    Science.gov (United States)

    Gabriel, José Luis; Vanclooster, Marnik; Garrido, Alberto; Quemada, Miguel

    2013-04-01

    Introducing cover crops interspersed with intensively fertilized crops in rotation has the potential to reduce nitrate leaching. However, despite the evident environmental services provided and the range of agronomic benefits documented in the literature, farmers' adoption of the technique is still limited because growing CC could lead to extra costs for the farm in three different forms: direct, indirect, and opportunity costs. Environmental studies are complex, and evaluating the indicators that are representative of the environmental impact of an agricultural system is a complicated task that is conducted by specialized groups and methodologies. Multidisciplinary studies may help to develop reliable approaches that would contribute to choosing the best agricultural strategies based on linking economic and environmental benefits. This study evaluates barley (Hordeum vulgare L., cv. Vanessa), vetch (Vicia villosa L., cv. Vereda) and rapeseed (Brassica napus L., cv. Licapo) as cover crops between maize, leaving the residue in the ground or selling it for animal feeding, and compares the economic and environmental results with respect to a typical maize-fallow rotation. Nitrate leaching for different weather conditions was calculated using the mechanistic-deterministic WAVE model, using the Richards equation parameterised with a conceptual model for the soil hydraulic properties for describing the water flow in the vadose zone, combined with field observed data. The economic impact was evaluated through stochastic (Monte-Carlo) simulation models of farms' profits using probability distribution functions of maize yield and cover crop biomass developed fitted with data collected from various field trials (during more than 5 years) and probability distribution functions of maize and different cover crop forage prices fitted from statistical sources. Stochastic dominance relationships are obtained to rank the most profitable strategies from a farm financial perspective

  11. Performance of Flooded Rice Grown in Succession to Winter Cover Crops

    Directory of Open Access Journals (Sweden)

    Silmara da Correia Luz

    2018-02-01

    Full Text Available ABSTRACT: Mean grain yield of flooded rice in southern Brazil has increased in recent years due to the use of high-yield cultivars and improvement of crop management practices. Nevertheless, stagnation in grain yields has been observed in some rice-producing regions. Adoption of conservation tillage systems based on cover crops may be a strategy to increase rice grain yield potential. The objective of the present study was to evaluate the effect of winter cover crops on initial establishment, development, and grain yield of flooded rice (Oryza sativa L. grown under different fertilization levels and no-tillage. A field experiment was carried out for three consecutive years (2010/11, 2011/12, and 2012/13 in Cachoeirinha, Rio Grande do Sul, South Brazil. Treatments included three winter cover crops [ryegrass (Lolium multiflorum Lam., native serradella (Ornithopus micranthus Benth., and a ryegrass-serradella mixture] and fallow, and three fertilization levels for rice grown in succession. More than 3 Mg ha−1 of serradella aboveground residue or 4 Mg ha−1 of ryegrass residue limited rice emergence in the first year when rainfall in the sowing-emergence period was higher than in the second and third years. In contrast, a large amount of residue (serradella >2 Mg ha−1; ryegrass >3 Mg ha−1 was beneficial to rice emergence when rainfall was low in the sowing-emergence period of the second and third years. The serradella cover crop increased rice aboveground biomass at anthesis by 22 % compared to the ryegrass cover crop. Furthermore, rice grain yield was 15 % higher in succession to serradella than to ryegrass in the third year. Continuous cultivation of flooded rice in succession to ryegrass over three years reduced grain yield by around 1.4 Mg ha−1, regardless of fertilization level. Fertilization for very high production expectations increased rice grain yield in all years, especially in the second year, when solar radiation was higher than

  12. Effect of a Terminated Cover Crop and Aldicarb on Cotton Yield and Meloidogyne incognita Population Density.

    Science.gov (United States)

    Wheeler, T A; Leser, J F; Keeling, J W; Mullinix, B

    2008-06-01

    Terminated small grain cover crops are valuable in light textured soils to reduce wind and rain erosion and for protection of young cotton seedlings. A three-year study was conducted to determine the impact of terminated small grain winter cover crops, which are hosts for Meloidogyne incognita, on cotton yield, root galling and nematode midseason population density. The small plot test consisted of the cover treatment as the main plots (winter fallow, oats, rye and wheat) and rate of aldicarb applied in-furrow at-plant (0, 0.59 and 0.84 kg a.i./ha) as subplots in a split-plot design with eight replications, arranged in a randomized complete block design. Roots of 10 cotton plants per plot were examined at approximately 35 days after planting. Root galling was affected by aldicarb rate (9.1, 3.8 and 3.4 galls/root system for 0, 0.59 and 0.84 kg aldicarb/ha), but not by cover crop. Soil samples were collected in mid-July and assayed for nematodes. The winter fallow plots had a lower density of M. incognita second-stage juveniles (J2) (transformed to Log(10) (J2 + 1)/500 cm(3) soil) than any of the cover crops (0.88, 1.58, 1.67 and 1.75 Log(10)(J2 + 1)/500 cm(3) soil for winter fallow, oats, rye and wheat, respectively). There were also fewer M. incognita eggs at midseason in the winter fallow (3,512, 7,953, 8,262 and 11,392 eggs/500 cm(3) soil for winter fallow, oats, rye and wheat, respectively). Yield (kg lint per ha) was increased by application of aldicarb (1,544, 1,710 and 1,697 for 0, 0.59 and 0.84 kg aldicarb/ha), but not by any cover crop treatments. These results were consistent over three years. The soil temperature at 15 cm depth, from when soils reached 18 degrees C to termination of the grass cover crop, averaged 9,588, 7,274 and 1,639 centigrade hours (with a minimum threshold of 10 degrees C), in 2005, 2006 and 2007, respectively. Under these conditions, potential reproduction of M. incognita on the cover crop did not result in a yield penalty.

  13. Organic farming and cover crops as an alternative to mineral fertilizers to improve soil physical properties

    Science.gov (United States)

    Sánchez de Cima, Diego; Luik, Anne; Reintam, Endla

    2015-10-01

    For testing how cover crops and different fertilization managements affect the soil physical properties in a plough based tillage system, a five-year crop rotation experiment (field pea, white potato, common barley undersown with red clover, red clover, and winter wheat) was set. The rotation was managed under four different farming systems: two conventional: with and without mineral fertilizers and two organic, both with winter cover crops (later ploughed and used as green manure) and one where cattle manure was added yearly. The measurements conducted were penetration resistance, soil water content, porosity, water permeability, and organic carbon. Yearly variations were linked to the number of tillage operations, and a cumulative effect of soil organic carbon in the soil as a result of the different fertilization amendments, organic or mineral. All the systems showed similar tendencies along the three years of study and differences were only found between the control and the other systems. Mineral fertilizers enhanced the overall physical soil conditions due to the higher yield in the system. In the organic systems, cover crops and cattle manure did not have a significant effect on soil physical properties in comparison with the conventional ones, which were kept bare during the winter period. The extra organic matter boosted the positive effect of crop rotation, but the higher number of tillage operations in both organic systems counteracted this effect to a greater or lesser extent.

  14. Cover crops mitigate direct greenhouse gases balance but reduce drainage under climate change scenarios in temperate climate with dry summers.

    Science.gov (United States)

    Tribouillois, Hélène; Constantin, Julie; Justes, Eric

    2018-02-14

    Cover crops provide ecosystem services such as storing atmospheric carbon in soils after incorporation of their residues. Cover crops also influence soil water balance, which can be an issue in temperate climates with dry summers as for example in southern France and Europe. As a consequence, it is necessary to understand cover crops' long-term influence on greenhouse gases (GHG) and water balances to assess their potential to mitigate climate change in arable cropping systems. We used the previously calibrated and validated soil-crop model STICS to simulate scenarios of cover crop introduction to assess their influence on rainfed and irrigated cropping systems and crop rotations distributed among five contrasted sites in southern France from 2007 to 2052. Our results showed that cover crops can improve mean direct GHG balance by 315 kg CO 2 e ha -1  year -1 in the long term compared to that of bare soil. This was due mainly to an increase in carbon storage in the soil despite a slight increase in N 2 O emissions which can be compensated by adapting fertilization. Cover crops also influence the water balance by reducing mean annual drainage by 20 mm/year but increasing mean annual evapotranspiration by 20 mm/year compared to those of bare soil. Using cover crops to improve the GHG balance may help to mitigate climate change by decreasing CO 2 e emitted in cropping systems which can represent a decrease from 4.5% to 9% of annual GHG emissions of the French agriculture and forestry sector. However, if not well managed, they also could create water management issues in watersheds with shallow groundwater. Relationships between cover crop biomass and its influence on several variables such as drainage, carbon sequestration, and GHG emissions could be used to extend our results to other conditions to assess the cover crops' influence in a wider range of areas. © 2018 John Wiley & Sons Ltd.

  15. New roller concepts for mechanical terminating cover crops in conservation agriculture in the southern United States

    Science.gov (United States)

    Rollers may provide a viable option to herbicides for terminating cover crops; however, excessive vibration generated by rollers and transferred to tractors hinders adoption of this technology in the US. To avoid excessive vibration, producers must limit their operational speed, which increases time...

  16. Soil physical properties and grape yield influenced by cover crops and management systems

    Directory of Open Access Journals (Sweden)

    Jaqueline Dalla Rosa

    2013-10-01

    Full Text Available The use of cover crops in vineyards is a conservation practice with the purpose of reducing soil erosion and improving the soil physical quality. The objective of this study was to evaluate cover crop species and management systems on soil physical properties and grape yield. The experiment was carried out in Bento Gonçalves, RS, Southern Brazil, on a Haplic Cambisol, in a vineyard established in 1989, using White and Rose Niagara grape (Vitis labrusca L. in a horizontal, overhead trellis system. The treatments were established in 2002, consisting of three cover crops: spontaneous species (SS, black oat (Avena strigosa Schreb (BO, and a mixture of white clover (Trifolium repens L., red clover (Trifolium pratense L. and annual rye-grass (Lolium multiflorum L. (MC. Two management systems were applied: desiccation with herbicide (D and mechanical mowing (M. Soil under a native forest (NF area was collected as a reference. The experimental design consisted of completely randomized blocks, with three replications. The soil physical properties in the vine rows were not influenced by cover crops and were similar to the native forest, with good quality of the soil structure. In the inter-rows, however, there was a reduction in biopores, macroporosity, total porosity and an increase in soil density, related to the compaction of the surface soil layer. The M system increased soil aggregate stability compared to the D system. The treatments affected grapevine yield only in years with excess or irregular rainfall.

  17. Sunn Hemp cover cropping and organic fertilizer effects on the nematode community under temperate growing conditions

    Science.gov (United States)

    Plantings of sunn hemp as a cover crop have been experimentally shown to improve soil health, reduce plant-parasitic nematodes, and increase nematode-antagonistic microorganisms. However, these studies have been largely conducted in tropical and subtropical regions. To investigate the impacts of sun...

  18. Utilization of sunn hemp for cover crops and weed control in temperate climates

    Science.gov (United States)

    The need to develop increasingly integrated pest management and sustainable food production systems has encouraged a greater interest to thoroughly evaluate effective utilization of cover crops in agricultural systems. Sunn hemp, a tropical legume that originated most likely from the Indo-Pakistani ...

  19. Sunn hemp as a cover crop to reduce nitrogen inputs for winter wheat

    Science.gov (United States)

    The tropical legume sunn hemp (Crotalaria juncea L.) has the potential to perform as a beneficial cover crop in the southeastern United States due to its ability to accumulate large amounts of biomass and symbiotic nitrogen (N) in a short period of time during the summer months. Planting sunn hemp,...

  20. Cover crops alter phosphorus soil fractions and organic matter accumulation in a Peruvian cacao agroforestry system

    Science.gov (United States)

    In many tropical soils, excessive weathering of primary minerals confounded by intense agricultural production has resulted in the depletion of organic matter and plant available forms of phosphorus (P). Long-term growth of cover crops in tropical agroforestry systems have been shown to influence nu...

  1. Fuzzy Multi Attributive Comparison of Roller Designs used to Terminate a Cover Crop

    Science.gov (United States)

    Cover crops are a vital part of conservation tillage systems, but they have to be managed appropriately to get their full benefits. These benefits include weed pressure reduction caused by alleopathy, improving soil properties due to mulch effects and increased soil organic matter. In recent years,...

  2. Tillage effects on N2O emissions as influenced by a winter cover crop

    DEFF Research Database (Denmark)

    Petersen, Søren O; Mutegi, James; Hansen, Elly Møller

    2011-01-01

    emissions may be more important than the effect on soil C. This study monitored emissions of N2O between September 2008 and May 2009 in three tillage treatments, i.e., conventional tillage (CT), reduced tillage (RT) and direct drilling (DD), all with (+CC) or without (−CC) fodder radish as a winter cover...... application by direct injection N2O emissions were stimulated in all tillage treatments, reaching 250–400 μg N m−2 h−1 except in the CT + CC treatment, where emissions peaked at 900 μg N m−2 h−1. Accumulated emissions ranged from 1.6 to 3.9 kg N2O ha−1. A strong positive interaction between cover crop......Conservation tillage practices are widely used to protect against soil erosion and soil C losses, whereas winter cover crops are used mainly to protect against N losses during autumn and winter. For the greenhouse gas balance of a cropping system the effect of reduced tillage and cover crops on N2O...

  3. Soil microbial communities under cacao agroforestry and cover crop systems in Peru

    Science.gov (United States)

    Cacao (Theobroma cacao) trees are grown in tropical regions worldwide for chocolate production. We studied the effects of agroforestry management systems and cover cropping on soil microbial communities under cacao in two different replicated field experiments in Peru. Two agroforestry systems, Imp...

  4. The Effect of Grazing by the Slug Arion Vulgaris, Arion Rufus and Deroceras Reticulatum (Gastropoda: Pulmonata: Stylommatophora on Leguminous Plants and other Small-Area Crops

    Directory of Open Access Journals (Sweden)

    Kozłowski Jan

    2014-07-01

    Full Text Available Herbivorous slugs do significant damage to many species of crop plants. A laboratory study was conducted to determine the rate and extent of damage caused to 16 plant species by Arion vulgaris, Arion rufus, and Deroceras reticulatum. It was found, that levels of damage caused to young plants of Brassica napus, Sorghum bicolor, Vicia faba, and Sinapis alba by the slugs A. vulgaris, A. rufus, and D. reticulatum were similar, while levels of damage caused to the other studied plants by particular slug species differed significantly. Based on the results of the damage by the investigated slug species, plants were categorised as heavily or lightly damaged.

  5. Phosphatase activity in sandy soil influenced by mycorrhizal and non-mycorrhizal cover crops

    Directory of Open Access Journals (Sweden)

    Alceu Kunze

    2011-06-01

    Full Text Available Cover crops may difffer in the way they affect rhizosphere microbiota nutrient dynamics. The purpose of this study was to evaluate the effect of mycorrhizal and non-mycorrhizal cover crops on soil phosphatase activity and its persistence in subsequent crops. A three-year experiment was carried out with a Typic Quartzipsamment. Treatments were winter species, either mycorrhizal black oat (Avena strigosa Schreb or the non-mycorrhizal species oilseed radish (Raphanus sativus L. var. oleiferus Metzg and corn spurry (Spergula arvensis L.. The control treatment consisted of resident vegetation (fallow in the winter season. In the summer, a mixture of pearl millet (Pennisetum americanum L. with sunnhemp (Crotalaria juncea L. or with soybean (Glycine max L. was sown in all plots. Soil cores (0-10 cm and root samples were collected in six growing seasons (winter and summer of each year. Microbial biomass P was determined by the fumigation-extraction method and phosphatase activity using p-nitrophenyl-phosphate as enzyme substrate. During the flowering stage of the winter cover crops, acid phosphatase activity was 30-35 % higher in soils with the non-mycorrhizal species oilseed radish, than in the control plots, regardless of the amount of P immobilized in microbial biomass. The values of enzyme activity were intermediate in the plots with corn spurry and black oat. Alkaline phosphatase activity was 10-fold lower and less sensitive to the treatments, despite the significant relationship between the two phosphatase activities. The effect of plant species on the soil enzyme profile continued in the subsequent periods, during the growth of mycorrhizal summer crops, after completion of the life cycle of the cover crops.

  6. Cover Crops and Fertilization Alter Nitrogen Loss in Organic and Conventional Conservation Agriculture Systems.

    Science.gov (United States)

    Shelton, Rebecca E; Jacobsen, Krista L; McCulley, Rebecca L

    2017-01-01

    Agroecosystem nitrogen (N) loss produces greenhouse gases, induces eutrophication, and is costly for farmers; therefore, conservation agricultural management practices aimed at reducing N loss are increasingly adopted. However, the ecosystem consequences of these practices have not been well-studied. We quantified N loss via leaching, NH 3 volatilization, N 2 O emissions, and N retention in plant and soil pools of corn conservation agroecosystems in Kentucky, USA. Three systems were evaluated: (1) an unfertilized, organic system with cover crops hairy vetch ( Vicia villosa ), winter wheat ( Triticum aestivum ), or a mix of the two (bi-culture); (2) an organic system with a hairy vetch cover crop employing three fertilization schemes (0 N, organic N, or a fertilizer N-credit approach); and (3) a conventional system with a winter wheat cover crop and three fertilization schemes (0 N, urea N, or organic N). In the unfertilized organic system, cover crop species affected NO 3 -N leaching (vetch > bi-culture > wheat) and N 2 O-N emissions and yield during corn growth (vetch, bi-culture > wheat). Fertilization increased soil inorganic N, gaseous N loss, N leaching, and yield in the organic vetch and conventional wheat systems. Fertilizer scheme affected the magnitude of growing season N 2 O-N loss in the organic vetch system (organic N > fertilizer N-credit) and the timing of loss (organic N delayed N 2 O-N loss vs. urea) and NO 3 -N leaching (urea > organic N) in the conventional wheat system, but had no effect on yield. Cover crop selection and N fertilization techniques can reduce N leaching and greenhouse gas emissions without sacrificing yield, thereby enhancing N conservation in both organic and conventional conservation agriculture systems.

  7. Cover Crops and Fertilization Alter Nitrogen Loss in Organic and Conventional Conservation Agriculture Systems

    Directory of Open Access Journals (Sweden)

    Rebecca E. Shelton

    2018-01-01

    Full Text Available Agroecosystem nitrogen (N loss produces greenhouse gases, induces eutrophication, and is costly for farmers; therefore, conservation agricultural management practices aimed at reducing N loss are increasingly adopted. However, the ecosystem consequences of these practices have not been well-studied. We quantified N loss via leaching, NH3 volatilization, N2O emissions, and N retention in plant and soil pools of corn conservation agroecosystems in Kentucky, USA. Three systems were evaluated: (1 an unfertilized, organic system with cover crops hairy vetch (Vicia villosa, winter wheat (Triticum aestivum, or a mix of the two (bi-culture; (2 an organic system with a hairy vetch cover crop employing three fertilization schemes (0 N, organic N, or a fertilizer N-credit approach; and (3 a conventional system with a winter wheat cover crop and three fertilization schemes (0 N, urea N, or organic N. In the unfertilized organic system, cover crop species affected NO3-N leaching (vetch > bi-culture > wheat and N2O-N emissions and yield during corn growth (vetch, bi-culture > wheat. Fertilization increased soil inorganic N, gaseous N loss, N leaching, and yield in the organic vetch and conventional wheat systems. Fertilizer scheme affected the magnitude of growing season N2O-N loss in the organic vetch system (organic N > fertilizer N-credit and the timing of loss (organic N delayed N2O-N loss vs. urea and NO3-N leaching (urea >> organic N in the conventional wheat system, but had no effect on yield. Cover crop selection and N fertilization techniques can reduce N leaching and greenhouse gas emissions without sacrificing yield, thereby enhancing N conservation in both organic and conventional conservation agriculture systems.

  8. Cover Crops and Fertilization Alter Nitrogen Loss in Organic and Conventional Conservation Agriculture Systems

    Science.gov (United States)

    Shelton, Rebecca E.; Jacobsen, Krista L.; McCulley, Rebecca L.

    2018-01-01

    Agroecosystem nitrogen (N) loss produces greenhouse gases, induces eutrophication, and is costly for farmers; therefore, conservation agricultural management practices aimed at reducing N loss are increasingly adopted. However, the ecosystem consequences of these practices have not been well-studied. We quantified N loss via leaching, NH3 volatilization, N2O emissions, and N retention in plant and soil pools of corn conservation agroecosystems in Kentucky, USA. Three systems were evaluated: (1) an unfertilized, organic system with cover crops hairy vetch (Vicia villosa), winter wheat (Triticum aestivum), or a mix of the two (bi-culture); (2) an organic system with a hairy vetch cover crop employing three fertilization schemes (0 N, organic N, or a fertilizer N-credit approach); and (3) a conventional system with a winter wheat cover crop and three fertilization schemes (0 N, urea N, or organic N). In the unfertilized organic system, cover crop species affected NO3-N leaching (vetch > bi-culture > wheat) and N2O-N emissions and yield during corn growth (vetch, bi-culture > wheat). Fertilization increased soil inorganic N, gaseous N loss, N leaching, and yield in the organic vetch and conventional wheat systems. Fertilizer scheme affected the magnitude of growing season N2O-N loss in the organic vetch system (organic N > fertilizer N-credit) and the timing of loss (organic N delayed N2O-N loss vs. urea) and NO3-N leaching (urea >> organic N) in the conventional wheat system, but had no effect on yield. Cover crop selection and N fertilization techniques can reduce N leaching and greenhouse gas emissions without sacrificing yield, thereby enhancing N conservation in both organic and conventional conservation agriculture systems. PMID:29403512

  9. Fitomassa e decomposição de resíduos de plantas de cobertura puras e consorciadas Biomass and decomposition of cover crop residues in monoculture and intercropping

    Directory of Open Access Journals (Sweden)

    Alexandre Doneda

    2012-12-01

    for cover crop species in consortium. The experiment was conducted in Não-Me-Toque, RS, on an Oxisol, evaluating nine treatments of four cover crops in monoculture [rye (Secale cereale L., oat (Avena strigosa Schreb, pea (Pisum sativum subsp. arvense, and wild radish (Raphanus sativus L. var. oleiferus Metzg] and five in intercropping [(rye + pea, radish + rye, oat + radish, rye + vetch (Vicia sativa L. and oat + vetch]. The decomposition dynamics of cover crop residues was evaluated in litter bags which were distributed on the soil surface and collected after seven, 14, 21, 28, 57, 117, and 164 days. Leguminous and cruciferous intercropped with Gramineae species resulted in greater biomass production compared to cultivation in monoculture. The nitrogen (N accumulated in the pea and wild radish plants intercropped with rye and oat was similar to the N in the leguminous and cruciferous monocultures and exceeded the N values observed for the Gramineae species in monoculture by 220.4 %. By intercropping cover crops it was possible to reduce the decomposition rate of crop residues compared to the monoculture of leguminous and cruciferous species.

  10. Protection against productivity versus erosion vineyards. Testing of vegetal covers in slope crops

    International Nuclear Information System (INIS)

    Marques, M. J.; Ruiz-Colmenero, M.; Garcia-Munoz, S.; Cabello, F.; Munoz-Organero, G.; Perez-Jimenez, M. A.; Bienes, R.

    2009-01-01

    Temporary and permanent cover crops were used in three rain fed vineyards in the Center of Spain. They were sown in the middle of the strips to assess their ability to control erosion as well as their influence on grape production. Data from the year 2008 are compared with those obtained with traditional tillage treatment. The permanent cover formed by Brachypodium distachyon showed better ability to control erosion but it produced a decrease in production in young vines. barley and rye treatments were temporary covers, mowed in spring. They also reduced the erosion compared with the tillage however they did not appear to affect the vineyard production. (Author)

  11. Influence of the nature and age of cover crop residues on the sorption of three pesticides

    Science.gov (United States)

    Cassigneul, Ana; Alletto, Lionel; Chuette, Delphine; Le Gac, Anne-Laure; Hatier, Jules; Etievant, Veronique; Bergheaud, Valérie; Baumberger, Stéphanie; Méchin, Valérie; Justes, Eric; Benoit, Pierre

    2013-04-01

    In agricultural fields, soil and water quality preservation is strongly influenced by pesticides use and behavior. To limit the environmental impacts of agricultural activities, best management practices such as the use of cover crops are encouraged. Cover crops during the fallow period were found to be efficient in reducing nitrate leaching, controlling soil erosion, improving soil organic content and enhancing soil biological activity. This technique was also found to modify soil water dynamics in the following crop. According to these effects, modifications on pesticide behavior in soil, such as sorption, degradation and transport, are expected (Alletto et al., 2012 ; 2013). In this study, the impact of the nature and level of decomposition of cover crop was studied on the sorption characteristics of three pesticides. These pesticides differed in their physicochemical characteristics (hydrophobicity, solubility, persistence) and were two herbicides, S-metolachlor and glyphosate, which are largely used in maize production and predominantly found as pollutants in water; and one fungicide, epoxiconazole. Correlations between pesticide sorption and physicochemical characteristics of the cover crop residues were studied. Residues of oat, turnip rape, red clover and phacelia were collected in March 2011 and incubated at 28°C and at the water holding capacity during 0, 6, 28 or 56 days. For each date, adsorption of the three radiolabeled pesticides was measured in batch on the different cover crop residues, and their biochemical composition (Van Soest fractionation), hydrophobicity (contact angle measurement) and C/N ratio were determined. Results showed that the adsorption of the pesticides differed significantly according to (i) the pesticide, (ii) the nature of cover crop, (iii) the decomposition level of the cover crop and the interaction cover crop x decomposition time. Epoxiconazole was the most adsorbed molecule, with Kd values ranging from 161 ± 30 L/Kg (oat

  12. Comparative Methods of Application of Wild Plant Parts on Growth and in the Control of Root Rot Fungi of Leguminous Crops

    International Nuclear Information System (INIS)

    Ikram, N.; Dawae, S.

    2016-01-01

    Present research work was carried out for the management of root rot fungi with wild plant part capsules and pellets formulation in soil. When application of pellets and capsules was carried out with Prosopis juliflora stem, leaves and flowers showed significant reduction in disease incidence and enhancement in growth and physiological parameters. Colonization of Fusarium spp., Macrophomina phaseolina and Rhizoctonia solani was completely suppressed when P. juliflora leaves pellets incorporated in soil. Physiological parameters such as chlorophyll a and b and protein were significantly increased when leaves pellets incorporated in soil at the rate of 1 percent w/w so P. juliflora leaves pellets were most effective in the control of root rot fungi and enhanced the growth of crop plants. (author)

  13. Allelopathic effects of water extracts of Sorghum halepense (L. Pers., Convolvulus arvensis L. and Cirsium arvense Scop. on early seedling growth of some leguminous crops

    Directory of Open Access Journals (Sweden)

    Irena Golubinova

    2014-03-01

    Full Text Available In order to study the allelopathic effect of aboveground dry biomass of Sorghum halepense, Convolvulus arvensis and Cirsium arvense on seed germination and early seedling growth of Pisum sativum (L., varieties Mir (winter form and Kerpo (spring form; Vicia sativa (L., variety Tempo, and Medicago sativa (L., variety Dara, a laboratory experiment was conducted at the Institute of Forage Crops - Pleven. Four concentrations: 1.25, 2.5, 5.0 and 10.0% were applied to each weed biotype used to study allelopathic effects. The results showed that weed extracts significantly decreased germination percentage, shoot and root length (cm, shoot and root weight (g, and seed vigor index (SVI1 and SVI2 of the tested species. In general, the variable effects are related to the weed species and extract concentrations.

  14. Morphostructural characterization of soil conventionally tilled with mechanized and animal traction with and without cover crop

    Directory of Open Access Journals (Sweden)

    Ricardo Ralisch

    2010-12-01

    Full Text Available The structural stability and restructuring ability of a soil are related to the methods of crop management and soil preparation. A recommended strategy to reduce the effects of soil preparation is to use crop rotation and cover crops that help conserve and restore the soil structure. The aim of this study was to evaluate and quantify the homogeneous morphological units in soil under conventional mechanized tillage and animal traction, as well as to assess the effect on the soil structure of intercropping with jack bean (Canavalia ensiformis L.. Profiles were analyzed in April of 2006, in five counties in the Southern-Central region of Paraná State (Brazil, on family farms producing maize (Zea mays L., sometimes intercropped with jack bean. The current structures in the crop profile were analyzed using Geographic Information Systems (GIS and subsequently principal component analysis (PCA to generate statistics. Morphostructural soil analysis showed a predominance of compact units in areas of high-intensity cultivation under mechanized traction. The cover crop did not improve the structure of the soil with low porosity and compact units that hamper the root system growth. In areas exposed to animal traction, a predominance of cracked units was observed, where roots grew around the clods and along the gaps between them.

  15. Winter annual cover crop has only minor effects on major corn arthropod pests.

    Science.gov (United States)

    Davis, Holly N; Currie, Randall S; Klocke, Norman L; Buschman, Lawrent L

    2010-04-01

    We studied the effects of downy brome, Bromus tectorum L., winter cover crop on several corn, Zea mays L., pests in the summer crop after the cover crop. An experiment was conducted that consisted of two trials with two levels of irrigation, two levels of weed control, and two levels of downy brome. Corn was grown three consecutive years after the downy brome grown during the winter. Banks grass mites, Oligonychus pratensis (Banks), twospotted spider mites, Tetranychus urticae Koch, and predatory mites from the genus Neoseiulus were present in downy brome at the beginning of the growing season. They moved into corn, but their numbers did not differ significantly across the treatments. Larval western corn rootworm, Diabrotica virgifera virgifera LeConte, feeding on corn roots was evaluated the second and third years of corn, production. Irrigation and herbicide treatments had no significant effects on rootworm injury levels. In one trial, rootworm injury ratings were significantly greater in treatments with a history of high versus low brome, but this effect was not significant in the other trial. Rootworm injury seemed to be similar across plots with different surface soil moistures. This suggests that the use of a winter cover crop such as downy brome will not have a major negative impact the arthropods studied.

  16. Nitrogen Transfer from Cover Crop Residues to Onion Grown under Minimum Tillage in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Leoncio de Paula Koucher

    2017-08-01

    Full Text Available ABSTRACT Nitrogen derived from cover crop residues may contribute to the nutrition of onion grown under minimum tillage (MT and cultivated in rotation. The aim of this study was to evaluate the N transferred from different cover crop residues to the onion crop cultivated under MT in southern Brazil. In June 2014, oilseed radish, black oat, and oilseed radish + black oat residues labeled with 15N were deposited on the soil surface before transplanting onions. During the growth season and at harvest, young expanded onion leaves, complete plants, and samples from different soil layers were collected and analyzed for recovery of 15N-labeled residue. Oilseed radish decomposed faster than other residues and 4 % of residue N was recovered in leaves and bulbs at harvest, but in general, N in plant organs was derived from sources other than the cover crop residues. In addition, leaf N was in the proper range for all treatments and was adequately mobilized to the bases for bulbing. The N derived from decomposing residues contributed little to onion development and the use of these plants should be chosen based on their advantages for physical and biological soil quality.

  17. Effect of water content and organic carbon on remote sensing of crop residue cover

    Science.gov (United States)

    Serbin, G.; Hunt, E. R., Jr.; Daughtry, C. S. T.; McCarty, G. W.; Brown, D. J.; Doraiswamy, P. C.

    2009-04-01

    Crop residue cover is an important indicator of tillage method. Remote sensing of crop residue cover is an attractive and efficient method when compared with traditional ground-based methods, e.g., the line-point transect or windshield survey. A number of spectral indices have been devised for residue cover estimation. Of these, the most effective are those in the shortwave infrared portion of the spectrum, situated between 1950 and 2500 nm. These indices include the hyperspectral Cellulose Absorption Index (CAI), and advanced multispectral indices, i.e., the Lignin-Cellulose Absorption (LCA) index and the Shortwave Infrared Normalized Difference Residue Index (SINDRI), which were devised for the NASA Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor. Spectra of numerous soils from U.S. Corn Belt (Indiana and Iowa) were acquired under wetness conditions varying from saturation to oven-dry conditions. The behavior of soil reflectance with water content was also dependent on the soil organic carbon content (SOC) of the soils, and the location of the spectral bands relative to significant water absorptions. High-SOC soils showed the least change in spectral index values with increase in soil water content. Low-SOC soils, on the other hand, showed measurable difference. For CAI, low-SOC soils show an initial decrease in index value followed by an increase, due to the way that water content affects CAI spectral bands. Crop residue CAI values decrease with water content. For LCA, water content increases decrease crop residue index values and increase them for soils, resulting in decreased contrast. SINDRI is also affected by SOC and water content. As such, spatial information on the distribution of surface soil water content and SOC, when used in a geographic information system (GIS), will improve the accuracy of remotely-sensed crop residue cover estimates.

  18. Reducing nitrate loss in tile drainage water with cover crops and water-table management systems.

    Science.gov (United States)

    Drury, C F; Tan, C S; Welacky, T W; Reynolds, W D; Zhang, T Q; Oloya, T O; McLaughlin, N B; Gaynor, J D

    2014-03-01

    Nitrate lost from agricultural soils is an economic cost to producers, an environmental concern when it enters rivers and lakes, and a health risk when it enters wells and aquifers used for drinking water. Planting a winter wheat cover crop (CC) and/or use of controlled tile drainage-subirrigation (CDS) may reduce losses of nitrate (NO) relative to no cover crop (NCC) and/or traditional unrestricted tile drainage (UTD). A 6-yr (1999-2005) corn-soybean study was conducted to determine the effectiveness of CC+CDS, CC+UTD, NCC+CDS, and NCC+UTD treatments for reducing NO loss. Flow volume and NO concentration in surface runoff and tile drainage were measured continuously, and CC reduced the 5-yr flow-weighted mean (FWM) NO concentration in tile drainage water by 21 to 38% and cumulative NO loss by 14 to 16% relative to NCC. Controlled tile drainage-subirrigation reduced FWM NO concentration by 15 to 33% and cumulative NO loss by 38 to 39% relative to UTD. When CC and CDS were combined, 5-yr cumulative FWM NO concentrations and loss in tile drainage were decreased by 47% (from 9.45 to 4.99 mg N L and from 102 to 53.6 kg N ha) relative to NCC+UTD. The reductions in runoff and concomitant increases in tile drainage under CC occurred primarily because of increases in near-surface soil hydraulic conductivity. Cover crops increased corn grain yields by 4 to 7% in 2004 increased 3-yr average soybean yields by 8 to 15%, whereas CDS did not affect corn or soybean yields over the 6 yr. The combined use of a cover crop and water-table management system was highly effective for reducing NO loss from cool, humid agricultural soils. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  19. Earthworm populations are affected from Long-Term Crop Sequences and Bio-Covers under No-Tillage

    Science.gov (United States)

    Earthworms are crucial for improving soil biophysical properties in cropping systems. Consequently, effects of cropping rotation and bio-covers were assessed on earthworm populations under no-tillage sites. Main effects of 6 different cropping sequences [corn (Zea mays), cotton (Gossypium hirsutum),...

  20. EFFECT OF DIFFERENT COVER CROP RESIDUES, MANAGEMENT PRACTICES ON SOIL MOISTURE CONTENT UNDER A TOMATO CROP (LYCOPERSICON ESCULENTUM

    Directory of Open Access Journals (Sweden)

    George Njomo Karuku

    2014-12-01

    Full Text Available SUMMARYThe soil water storage, soil water content, available water content and soil water balance under various cover crop residue management practices in a Nitisol were evaluated in a field experiment at the Kabete Field Station, University of Nairobi. The effects of surface mulching, above and below ground biomass and roots only incorporated of (mucuna pruriens, Tanzanian sunnhemp (Crotalaria ochroleuca and Vetch (Vicia benghalensis cover crops, fertilizer and non fertilized plots on soil water balance were studied. Tomato (Lycopersicon esculentum was used as the test crop. Since water content was close to field capacity, the drainage component at 100 cm soil depth was negligible and evapotranspiration was therefore derived from the change in soil moisture storage and precipitation. Residue management showed that above and below ground biomass incorporated optimized the partitioning of the water balance components, increasing moisture storage, leading to increased tomato yields and water use efficiency. Furthermore, vetch above and below ground biomass incorporated significantly improved the quantity and frequency of deep percolation. Soil fertilization (F and non fertilization (NF caused the most unfavourable partitioning of water balance, leading to the lowest yield and WUE. Tomato yields ranged from 4.1 in NF to 7.4 Mg ha-1 in Vetch treated plots. Vetch above and belowground biomass incorporated had significant (p ≤ 0.1 yields of 11.4 Mg ha-1 compared to all other residue management systems. Vetch residue treatment had the highest WUE (22.7 kg mm-1 ha-1 followed by mucuna treated plots (20.7 kg mm-1 ha-1 and both were significantly different (p ≤ 0.05 compared to the others irrespective of residue management practices.

  1. Cover crop management influences residue biomass and subsequent weed suppression in a conservation agriculture corn and cotton rotation

    Science.gov (United States)

    Use of winter cover crops is an integral component of conservation systems in corn and cotton. However, data concerning cover management and subsequent residue and weed biomass is needed. Field experiments were conducted from autumn of 2003 through cash crop harvest in 2006 at the Alabama Agricultur...

  2. A powered roller/crimper for walk-behind tractors to terminate cover crops in conservation agriculture

    Science.gov (United States)

    Roller/crimper implements have been used in large conservation farming systems to terminate cover crops near maturity and flatten them down to create a mulch through which cash crops can be planted directly into the cover residue. On small farms, tractors are usually small and less powerful relative...

  3. Short-term winter wheat (Triticum aestivum L.) cover crop grazing influence on calf growth, grain yield, and soil properties

    Science.gov (United States)

    Winter cover cropping has many agronomic benefits and can provide forages base for spring livestock grazing. Winter cover crop grazing has shown immediate economic benefits through increased animal production. Winter wheat pasture grazing is common in beef cow-calf production and stocker operations....

  4. Establishment of five cover crops and total soil nutrient extraction in a humid tropical soil in the Peruvian Amazon

    Science.gov (United States)

    In order to evaluate the establishment of five cover crops and their potential to increase soil fertility through nutrient extraction, an experiment was installed in the Research Station of Choclino, San Martin, Peru. Five cover crops were planted: Arachis pintoi Krapov. & W.C. Greg, Calopogonium m...

  5. Brachiaria as a Cover Crop to Improve Phosphorus Use Efficiency in a No-till Oxisol

    Directory of Open Access Journals (Sweden)

    Moniki Campos Janegitz

    Full Text Available ABSTRACT Oxidic soils are phosphorus drains in soil; hence, P availability is a limiting factor in tropical, weathered Oxidic soils. It has been shown that some brachiarias grown as cover crops may increase soil available P to subsequent crops. The objective of this study was to evaluate soil P cycling and availability, as well as the response of soybean to soluble and natural reactive phosphates as affected by ruzi grass (Urochloa ruziziensis, R. Germ. and C.M. Evrard, Crin grown as a cover crop in a no-till system. Experimental treatments consisted of the presence or absence of ruzi grass in combination with a control (0.0 P and soluble and reactive rock phosphate broadcast on the soil surface in the winter (80 kg ha-1 P2O5, plus three rates of P applied to soybean furrows (0, 30, and 60 kg ha-1 of P2O5 at planting, in the form of triple superphosphate. Soybean was cropped in two seasons: 2010/2011 and 2011/2012. Soil samples were taken before soybean planting (after desiccation of Brachiaria at 0.00-0.05 and 0.05-0.10 m for soil available P. Total weight of dry matter and P accumulated in ruzi grass were determined, as well as soybean yields, P in soybean grains, and P use efficiency (PUE. The use of natural phosphate increased soil P availability. The highest yields were obtained with higher application rates of triple superphosphate in the planting furrow combined with broadcast rock phosphate. Broadcast application of Arad reactive phosphate increases and maintains soil available P, and this practice, associated with ruzi grass grown as a cover crop and the use of triple superphosphate applied to soybean furrows, results in higher use of P by soybeans.

  6. Entisol land characteristics with and without cover crop (Mucuna bracteata) on rubber plantation

    Science.gov (United States)

    Sakiah; Sembiring, M.; Hasibuan, J.

    2018-02-01

    Optimal nutrient delivery is one way to improve the quality and quantity of crop production. This is because the crops needs for nutrient is quite high, while the soil capacity in providing nutrients is limited. In addition to fertilization, nutrients can be given in the form of added organic material or planted as cover crop. The research took place from April to August 2016 in Bandar Pinang, Bandar Sumatera Indonesia Ltd. (SIPEF Group) plantation, with survey method. Soil samples were taken based on: Topography (flat and slope 15-30%), cover crop (with or without Mucuna bracteata) and plant age (seedling periods 1, 2 and 3). The soil sample is taken composite by zig zag method. The observed parameters were organic matter, N total, soil texture, bulk density and infiltration rate. Mucuna bracteata planting increased the contain of soil organic matter by 30.43% in flat area and 53.33% in hilly area, amount of N total soil by 27.27% in flat area and 7.69% at hilly area, bulk density 3.73 % In flat area and 0.41% in hilly area, soil infiltration by 48.88% with sandy clay dominant soil texture.

  7. Soil amendments with Brassica cover crops for management of Phytophthora blight on squash.

    Science.gov (United States)

    Ji, Pingsheng; Koné, Daouda; Yin, Jingfang; Jackson, Kimberly L; Csinos, Alexander S

    2012-04-01

    Phytophthora blight induced by Phytophthora capsici is responsible for serious yield loss in vegetable production in the United States and other countries. This study was conducted to evaluate the efficacy of Brassica cover crops used as soil amendments for managing Phytophthora blight of squash. In greenhouse studies, disease incidence on squash plants was significantly reduced by soil amendment with mustard shoots or roots used at 1 and 2.5% (plant tissue/soil, w/w). The shoots of canola used at 1 or 2.5% also suppressed disease, while the roots of canola or other crops did not reduce disease significantly. In field studies, soil amendments with mustard and canola provided the greatest disease reduction and increased squash yield significantly compared with the non-treated control. Mustard and canola did not appear to be susceptible to P. capsici. The results indicated that some Brassica crops, particularly mustard and canola, had the potential to significantly reduce Phytophthora blight on squash when used as soil amendments. As P. capsici has a remarkable ability to develop resistance to chemical fungicides, use of effective Brassica cover crops could be a biorational alternative to fungicides and a valuable component in developing integrated disease management programs. Copyright © 2011 Society of Chemical Industry.

  8. The effects of cover crop on weed control in collard (Brassica olerecea var acephala) and lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Mennan, H; Ngouajio, M; Isik, D; Kose, B; Kaya, E

    2006-01-01

    Leafy vegetables are not very competitive and weed interference can cause considerable yield losses in collard (Brassica olerecea var acephala) and lettuce (Lactuca sativa L.). Currently there are no pre or post emergence herbicides registered for weed control in these vegetables in Turkey. For this reason, alternative weed control strategies need to be developed. Cover crop residue could represent an alternative method of weed management in these crops. Field studies were conducted in 2004 at the Black Sea Agricultural Research Institute experimental field in Samsun, Turkey. The cover crop treatments consisted of Sorghum bicolor (L.) Moench, Sorghum vulgare Pers., Vicia villosa L., Amaranthus cruentus L., Pisum sativum L. and the bare ground with no cover crop. All cover crops were seeded by hand and incorporated into the soil on 11 May, 2004. Each plot was 10 m2 (2 x 5 m) and arranged in a randomized complete block design with four replications. All cover crops were incorporated into the soil by discing on 1 September 2004 at flowering stage of the cover crops. Broadleaved weed species were dominant in the experimental area. Most cover crops established well and S. bicolor biomass was the highest. The number of weed species emerging in all treatments was different at 14 DAD (days after desiccation). Similar results were observed at 28 and 56 DAD. Treatments with Vicia villosa residues had fewer weed species and lower total weed densities than other treatments.

  9. Soil microbial functionality in response to the inclusion of cover crop mixtures in agricultural systems

    Energy Technology Data Exchange (ETDEWEB)

    Chavarría, D.N.; Verdenelli, R.A.; Muñoz, M.J.; Conforto, C.; Restovich, S.B.; Andriulo, A.E.; Meriles, J.M.; Vargas-Gil, S.

    2016-11-01

    Agricultural systems where monoculture prevails are characterized by fertility losses and reduced contribution to ecosystem services. Including cover crops (CC) as part of an agricultural system is a promising choice in sustainable intensification of those demanding systems. We evaluated soil microbial functionality in cash crops in response to the inclusion of CC by analyzing soil microbial functions at two different periods of the agricultural year (cash crop harvest and CC desiccation) during 2013 and 2014. Three plant species were used as CC: oat (Avena sativa L.), vetch (Vicia sativa L.) and radish (Raphanus sativus L.) which weresown in two different mixtures of species: oat and radish mix (CC1) and oat, radish and vetch mix (CC2), with soybean monoculture and soybean/corn being the cash crops. The study of community level physiological profiles showed statistical differences in respiration of specific C sources indicating an improvement of catabolic diversity in CC treatments. Soil enzyme activities were also increased with the inclusion of CC mixtures, with values of dehydrogenase activity and fluorescein diacetate hydrolysis up to 38.1% and 35.3% higher than those of the control treatment, respectively. This research evidenced that CC inclusion promotes soil biological quality through a contribution of soil organic carbon, improving the sustainability of agrosystems. The use of a CC mixture of three plant species including the legume vetch increased soil biological processes and catabolic diversity, with no adverse effects on cash crop grain yield. (Author)

  10. Fate of glyphosate and degradates in cover crop residues and underlying soil: A laboratory study

    Energy Technology Data Exchange (ETDEWEB)

    Cassigneul, A. [Université de Toulouse — École d' ingénieurs de Purpan, UMR 1248 AGIR — 75, Voie du TOEC BP 57 611, 31 076, Toulouse cedex 3 (France); INRA, UMR 1402 ECOSYS, 78850 Thiverval-Grignon (France); Benoit, P.; Bergheaud, V.; Dumeny, V.; Etiévant, V. [INRA, UMR 1402 ECOSYS, 78850 Thiverval-Grignon (France); Goubard, Y. [AgroParisTech, UMR 1402 ECOSYS, 78850 Thiverval-Grignon (France); Maylin, A. [Université de Toulouse — École d' ingénieurs de Purpan, UMR 1248 AGIR — 75, Voie du TOEC BP 57 611, 31 076, Toulouse cedex 3 (France); Justes, E. [INRA, UMR 1248 AGIR Auzeville — BP 52 627, 31 326, Castanet-Tolosan cedex (France); Alletto, L. [Université de Toulouse — École d' ingénieurs de Purpan, UMR 1248 AGIR — 75, Voie du TOEC BP 57 611, 31 076, Toulouse cedex 3 (France)

    2016-03-01

    The increasing use of cover crops (CC) may lead to an increase in glyphosate application for their destruction. Sorption and degradation of {sup 14}C-glyphosate on and within 4 decaying CC-amended soils were compared to its fate in a bare soil. {sup 14}C-Glyphosate and its metabolites distribution between mineralized, water-soluble, NH{sub 4}OH-soluble and non-extractable fractions was determined at 5 dates during a 20 °C/84-d period. The presence of CC extends {sup 14}C-glyphosate degradation half-life from 7 to 28 days depending on the CC. {sup 14}C-Glyphosate dissipation occurred mainly through mineralization in soils and through mineralization and bound residue formation in decaying CC. Differences in sorption and degradation levels were attributed to differences in composition and availability to microorganisms. CC- and soil-specific dissipation patterns were established with the help of explicit relationships between extractability and microbial activity. - Highlights: • Glyphosate sorption on cover crop residues increases with their decomposition degree. • Glyphosate degradation and mineralization are lower in mulch than in soil. • Nonextractable residue formation is one of the main dissipation pathways of glyphosate in cover crop mulch.

  11. Effect of management systems and cover crops on organic matter dynamics of soil under vegetables

    Directory of Open Access Journals (Sweden)

    Rodrigo Fernandes de Souza

    2014-06-01

    Full Text Available Vegetable production in conservation tillage has increased in Brazil, with positive effects on the soil quality. Since management systems alter the quantity and quality of organic matter, this study evaluated the influence of different management systems and cover crops on the organic matter dynamics of a dystrophic Red Latosol under vegetables. The treatments consisted of the combination of three soil tillage systems: no-tillage (NT, reduced tillage (RT and conventional tillage (CT and of two cover crops: maize monoculture and maize-mucuna intercrop. Vegetables were grown in the winter and the cover crops in the summer for straw production. The experiment was arranged in a randomized block design with four replications. Soil samples were collected between the crop rows in three layers (0.0-0.05, 0.05-0.10, and 0.10-0.30 m twice: in October, before planting cover crops for straw, and in July, during vegetable cultivation. The total organic carbon (TOC, microbial biomass carbon (MBC, oxidizable fractions, and the carbon fractions fulvic acid (C FA, humic acid (C HA and humin (C HUM were determined. The main changes in these properties occurred in the upper layers (0.0-0.05 and 0.05-0.10 m where, in general, TOC levels were highest in NT with maize straw. The MBC levels were lowest in CT systems, indicating sensitivity to soil disturbance. Under mucuna, the levels of C HA were lower in RT than NT systems, while the C FA levels were lower in RT than CT. For vegetable production, the C HUM values were lowest in the 0.05-0.10 m layer under CT. With regard to the oxidizable fractions, the tillage systems differed only in the most labile C fractions, with higher levels in NT than CT in the 0.0-0.05 m layer in both summer and winter, with no differences between these systems in the other layers. The cabbage yield was not influenced by the soil management system, but benefited from the mulch production of the preceding maize-mucuna intercrop as cover

  12. Occurrence of leguminous trees

    Energy Technology Data Exchange (ETDEWEB)

    Kirkbride, J.H.; Arkcoll, D.B.A.; Turnbull, J.W.; Magalhaes, L.M.S.; Fernandes, N.P.

    1984-01-01

    Five papers from the symposium are presented. Kirkbride, J.H. Jr.; Legumes of the cerrado. pp 23-46 (Refs. 55) A review is given. Some 548 legume species in 59 genera are listed that have been reported from cerrado vegetation. Felker, P.; Legume trees in semi-arid and arid areas. pp 47-59 (Refs. 41) A review is given of worldwide research activities. Arkcoll, D.B.; A comparison of some fast growing species suitable for woodlots in the wet tropics. pp 61-68 (Refs. 9) Studies are described near Manaus on intensive silviculture (for fuelwood production) of Eucalyptus deglupta, Cedrelinga catanaeformis (catenaeformis), Jacaranda copaia, and Inga edulis. Turnbull, J.W.; Six phyllodinous Acacia species for planting in the humid tropical lowlands. pp 69-73 (Refs. 14) Distribution, ecology, growth, and utilization are described for A. auriculiformis, A. mangium, A. aulacocarpa, A. crassicarpa, A. cincinnata, and A. polystachya. Magalhaes, L.M.S., Fernandes, N.P.; Experimental stands of leguminous trees in the Manaus region. pp 75-79 (Refs. 8) Performance up to age 20 yr of Cedrelinga catenaeformis, Dalbergia nigra, Dinizia excelsa, Dipteryx odorata, Dipteryx sp., Diplotropis sp., Eperua bijuga, Pithecellobium racemosum, Vouacapoua pallidior, and Hymenaea sp. is described.

  13. Lopsided oat (Avena strigosa as a new summer annual cover crop for weed suppression in Central Europe

    Directory of Open Access Journals (Sweden)

    Brust, Jochen

    2012-03-01

    Full Text Available Lopsided oat (Avena strigosa has been cultivated for many years, especially in Brazil, as a summer annual cover crop. Experiments were conducted in Stuttgart-Hohenheim in 2010 to estimate the capability of lopsided oat, yellow mustard (Sinapis alba, phacelia (Phacelia tanacetifolia and a cover crop mixture to suppress weeds and volunteer wheat. A pot experiment was conducted to analyze the emergence and growth of the different cover crop species. Twelve weeks after planting, lopsided oat produced 20.7 dt/ha of shoot- and 5.5 dt/ha of root dry matter. A field experiment was established in the summer after harvest of winter wheat. The soil was cultivated with a disc harrow and the cover crops were sown one day later. At four week intervals, the plant density and dry matter of cover crops, weeds and volunteer wheat were determined. Twelve weeks after planting, lopsided oat produced 17.8 dt/ha shoot- and 6.2 dt/ha root dry matter. In the lopsided oat plots, shoot dry matter of weeds and volunteer wheat were reduced by 98 % compared with control plots without cover crops. This was the highest weed reduction of all cover crops studied. The root dry matter of weeds and volunteer wheat was reduced by 55 % to 97 % in all cover crops, compared to the control plots. Lopsided oat reduced the plant density of weeds and volunteer wheat. While there were 54.5 plants/m² in the control plots, only 5.5 plants/m² were counted in the lopsided oat plots. The results showed that lopsided oat has a high potential for suppression of weeds and volunteer wheat in autumn. It also enlarges the number of cultivated cover crops in Central Europe.

  14. Cover Crop Residue Amount and Quality Effects on Soil Organic Carbon Mineralization

    Directory of Open Access Journals (Sweden)

    Binod Ghimire

    2017-12-01

    Full Text Available Decline in soil organic carbon (SOC and the associated impacts on crop production under conventional farming raises concerns on how alternative management practices increase SOC sequestration and improve agricultural sustainability. This study aimed to understand SOC mineralization kinetics with different cover crop (CC residue amendments. Soil samples were collected from a fallow and three CC (pea, oat, and canola plots. Soil samples from the CC plots were manipulated with zero, five, and 10 Mg ha−1 of the respective CC residues. All soil samples were incubated for eight weeks, SOC mineralization was monitored, and the first order kinetic and parabolic equation models were fitted to the observed data for estimating labile SOC (C0, and the decomposition rate constant (k. Subsequent comparisons of fitted model parameters were based on the first order kinetic model. The C0 varied with the residue amount while k varied with CC type. C0 was 591–858% greater with 10 Mg ha−1 and 289–456% greater with five Mg ha−1 residue additions while k was 122–297% greater with 10 Mg ha−1 and 94–240% greater with five Mg ha−1 residue additions when compared to the fallow treatment. The CC residue stimulated cumulative carbon mineralization (Cmin irrespective of CC type, suggesting that cover cropping has potential to improve SOC cycling in agroecosystems.

  15. Alelopatia de cultivos de cobertura vegetal sobre plantas infestantes = Allelopathy of cover crop on weed plants

    Directory of Open Access Journals (Sweden)

    Luciene Kazue Tokura

    2006-07-01

    Full Text Available O presente trabalho avaliou o potencial alelopático de cultivos de cobertura vegetal de trigo, aveia preta, milheto, nabo forrageiro e colza sobre o desenvolvimento de plantas infestantes e verificou qual das coberturas vegetais exerce maior controle sobre as mesmas. Os cultivos de cobertura vegetal foram implantados sob preparo convencional (uma aração e uma gradagem no Núcleo Experimental de Engenharia Agrícola (NEEA, da Universidade Estadual do Oeste do Paraná (Unioeste, Cascavel, Estado do Paraná. Mensalmente, realizou-se o acompanhamento e identificação das plantas infestantes emersas nas áreas de cobertura vegetal no período de agosto de 2000 a agosto de 2001. Os resultados obtidos permitiram concluir que das espécies encontradas, o capim marmelada foi o que apresentou maior potencial alelopático e a erva-de-santa-maria o menor. As coberturasvegetais que apresentaram melhor controle do total de plantas infestantes presentes na área experimental, incluindo àquelas com reconhecido potencial alelopático, foram aveia preta, colza, nabo forrageiro e milheto.This work evaluated the cover crop allelopathic potential of wheat, black oat, pearl millet, turnip and rape on the development of weed plants. It also verified which cover crop has larger control on the weed plants. The cover crop was implanted under conventional tillage (one disk plowing plus one disk harrowing in the Experimental Nucleus of Agricultural Engineering (NEEA, of the State University of the West of Paraná (Unioeste, Cascavel, Paraná State. Monthly (from August 2000 to August 2001, weed plants identification in the cover crop area was made. Results showed that from the found species, the alexander grass was the one that presented larger allelopathic potential, and, the mexican-tea was the one that presented smaller control. The vegetable coverings that presented larger control of the total of weed plants in the experimental area, including those with

  16. Effect of Cover Crops and Nitrogen Fertilizer on Total Production of Forage Corn and Dry Weight of Weeds

    Directory of Open Access Journals (Sweden)

    R Fakhari

    2014-10-01

    Full Text Available To evaluate the effect of cover crops, split application of nitrogen and control weeds on forage corn and weed biomass a factorial experiment based on randomized complete block design with three replications and three factors was conducted at the Agricultural Research Station of Ardabil (Iran during 2012 crop year. The first factor was cover crops (consisting of winter rye, hairy vetch, berseem clover, with and without weeding as controls. The second factor was two levels of split application of 225 kg.ha-1 urea at two growth stages forage corn: the first level (N1= 1/2 at planting and 1/2 at 8-10 leaf stage, second level (N2= 1/3 at planting, 1/3 at 8-10 leaf and 1/3 one week before tasselling stage. The third factor consisted of two levels of weed control: weeding at 8 leaves and weeding one week before tasselling. Results showed that winter rye, hairy vetch and berseem clover cover crops decreased total weed dry weights up to 87, 82 and 65 % respectively as compared to control (without weeding. Cover crops and nitrogen application time had a significant effect on yield of fresh forage corn and cover crops. Based on the advantages of effective weed control and higher forage production of hairy vetch it can be recommended as proper cover crop.

  17. Allelopathic cover crop of rye for integrated weed control in sustainable agroecosystems

    Directory of Open Access Journals (Sweden)

    Vincenzo Tabaglio

    2013-02-01

    Full Text Available The allelopathic potential of rye (Secale cereale L. is mainly due to phytotoxic benzoxazinones, compounds that are produced and accumulated in young tissues to different degrees depending on cultivar and environmental influences. Living rye plants exude low levels of benzoxazinones, while cover crop residues can release from 12 to 20 kg ha–1. This paper summarizes the results obtained from several experiments performed in both controlled and field environments, in which rye was used as a cover crop to control summer weeds in a following maize crop. Significant differences in benzoxazinoid content were detected between rye cultivars. In controlled environments, rye mulches significantly reduced germination of some broadleaf weeds. Germination and seedling growth of Amaranthus retroflexus and Portulaca oleracea were particularly affected by the application of rye mulches, while Chenopodium album was hardly influenced and Abutilon theophrasti was advantaged by the presence of the mulch. With reference to the influence of agronomic factors on the production of benzoxazinoids, nitrogen fertilization increased the content of allelochemicals, although proportionally less than dry matter. The field trial established on no-till maize confirmed the significant weed suppressiveness of rye mulch, both for grass and broadleaf weeds. A significant positive interaction between nitrogen (N fertilization and notillage resulting in the suppression of broadleaf weeds was observed. The different behavior of the weeds in the presence of allelochemicals was explained in terms of differential uptake and translocation capabilities. The four summer weeds tested were able to grow in the presence of low amounts of benzoxazolin-2(3H-one (BOA, between 0.3 and 20 mmol g–1 fresh weight. Although there were considerable differences in their sensitivity to higher BOA concentrations, P. oleracea, A. retroflexus, and Ch. album represented a group of species with a consistent

  18. Cover crops for managing weeds, soil chemical fertility and nutritional status of organically grown orange orchard in Sicily

    Directory of Open Access Journals (Sweden)

    Rosario Paolo Mauro

    2015-06-01

    Full Text Available Cover crops can offer significant advantages in the agronomic management of citrus orchards in Mediterranean environments. Therefore, a three-year research was conducted in eastern Sicily aimed at studying the effects of four cover crop sequences (Sinapis arvensis-Trigonella foenum-graecum-T. foenum-graecum; Medicago scutellata-Avena sativa-Lolium perenne; Vicia faba minor-A. sativa-A. sativa; A. sativa-V. faba. minor-L. perenne on weeds, major soil chemical properties and nutritional status of an organically grown orange orchard. The results highlighted that, among the studied cover crop sequences, Vicia faba-Avena-Avena was the most beneficial for weeds control within the orchard (92%, of cover crop cover, and 586 and 89 g DW m–2 of cover crop aboveground biomass and weeds aboveground biomass, respectively. Overall, the chemical fertility of the soil was positively influenced. In particular, it was observed an increase of the content of total nitrogen and available phosphorus in the soil by both Sinapis-Trigonella-Trigonella (0.75 g kg–1 and 59.0 mg kg–1, respectively and Vicia faba-Avena-Avena (0.70 g kg–1 and 56.0 mg kg–1, respectively cover crop sequences. Medicago-Avena-Lolium sequence seemed to be the most useful to ensure a better nutritional status of the orange orchard.

  19. Linking the planting of cover crops to soil and water nutrient dynamics in Shatto Ditch Watershed, IN

    Science.gov (United States)

    Christopher, S. F.; Tank, J. L.; Hanrahan, B. R.; Mahl, U. H.; Huang, K.

    2013-12-01

    Tile drainage systems are common in the Midwest, and facilitate the transfer of excess inorganic nitrogen (N) and phosphorus (P) from agricultural soils to adjacent streams. These non-point sources contribute to elevated nutrient loads to tributaries in the Mississippi River Basin, which have been linked to widespread hypoxia and associated ecological and economic problems in the Gulf of Mexico. In agricultural areas dominated by row-crops, the planting of cover crops after the cash crop has been harvested offers a potential mechanism to reduce nutrient leaching from fields to tile drains in the off-season. In general, cover crops retain nutrients on fields and increase soil organic matter (SOM) content after they are harvested. The planting of cover crops also promotes immobilization of soil N and reduction in losses of dissolved P from soils due to reduced erosion, resulting in significantly less leaching to surface waters through tile drains. As part of a demonstration project in the Shatto Ditch Watershed, located in the Tippecanoe River Basin, IN, we are testing whether the planting of cover crops will influence soil nutrient and organic matter, and how cover crops alter the dynamics of nutrient leaching from tile drains. We have been sampling tile drain outflows on a twice-monthly sampling regime and have been measuring dissolved inorganic N and P concentrations in tile water since November 2012. During Spring 2013, tile drain nitrate concentrations sampled synoptically throughout the watershed ranged from 2.6 - 38.9 mg NO3- L -1 (mean = 17.2 +/- 1.6 mg NO3- L -1) with the lowest concentrations coming from fields planted in cover crops (range = 2.6 - 19.0 mg NO3- L -1, mean = 9.7 +/- 1.5 mg NO3- L -1). In contrast, soluble reactive phosphorus (SRP) concentrations were much lower in tile drain water and ranged from 7.5 - 182.7 μg L-1 (mean = 24.5 +/- 5.0 μg L-1 SRP) and preliminary data suggest that there were no differences between fields with and without

  20. Polarimetric Signatures from a Crop Covered Land Surface Measured by an L-band Polarimetric Radiometer

    DEFF Research Database (Denmark)

    Søbjærg, Sten Schmidl; Skou, Niels

    2003-01-01

    This paper describes preliminary results from field measurements of polarimetric azimuth signatures with the EMIRAD L-band polarimetric radiometer, performed over a land test site at the Institut National de la Recherche Agronomique in Avignon, France. Scans of 180 degrees in azimuth were carried...... out in order to identify an eventual dependence of the Stokes vector on the look-direction. Results indicate a clear signature, for bare soil as well as for the crop-covered surface, and variations of more than 10 K are observed....

  1. Assessing Natural Isothiocyanate Air Emissions after Field Incorporation of Mustard Cover Crop

    Energy Technology Data Exchange (ETDEWEB)

    Trott, Donna M.; LePage, Jane; Hebert, Vincent

    2012-01-01

    A regional air assessment was performed to characterize volatile natural isothiocyanate (NITC) compounds in air during soil incorporation of mustard cover crops in Washington State. Field air sampling and analytical methods were developed specific to three NITCs known to be present in air at appreciable concentrations during/after field incorporation. The maximum observed concentrations in air for the allyl, benzyl, and phenethyl isothiocyanates were respectively 188, 6.1, and 0.7 lg m-3 during mustard incorporation. Based on limited inhalation toxicity information, airborne NITC concentrations did not appear to pose an acute human inhalation exposure concern to field operators and bystanders.

  2. Cloud Cover Assessment for Operational Crop Monitoring Systems in Tropical Areas

    Directory of Open Access Journals (Sweden)

    Isaque Daniel Rocha Eberhardt

    2016-03-01

    Full Text Available The potential of optical remote sensing data to identify, map and monitor croplands is well recognized. However, clouds strongly limit the usefulness of optical imagery for these applications. This paper aims at assessing cloud cover conditions over four states in the tropical and sub-tropical Center-South region of Brazil to guide the development of an appropriate agricultural monitoring system based on Landsat-like imagery. Cloudiness was assessed during overlapping four months periods to match the typical length of crop cycles in the study area. The percentage of clear sky occurrence was computed from the 1 km resolution MODIS Cloud Mask product (MOD35 considering 14 years of data between July 2000 and June 2014. Results showed high seasonality of cloud occurrence within the crop year with strong variations across the study area. The maximum seasonality was observed for the two states in the northern part of the study area (i.e., the ones closer to the Equator line, which also presented the lowest averaged values (15% of clear sky occurrence during the main (summer cropping period (November to February. In these locations, optical data faces severe constraints for mapping summer crops. On the other hand, relatively favorable conditions were found in the southern part of the study region. In the South, clear sky values of around 45% were found and no significant clear sky seasonality was observed. Results underpin the challenges to implement an operational crop monitoring system based solely on optical remote sensing imagery in tropical and sub-tropical regions, in particular if short-cycle crops have to be monitored during the cloudy summer months. To cope with cloudiness issues, we recommend the use of new systems with higher repetition rates such as Sentinel-2. For local studies, Unmanned Aircraft Vehicles (UAVs might be used to augment the observing capability. Multi-sensor approaches combining optical and microwave data can be another

  3. Clover as a cover crop for weed suppression in an intercropping design. II: Competitive ability of several clover species

    NARCIS (Netherlands)

    Hollander, den N.G.; Bastiaans, L.; Kropff, M.J.

    2007-01-01

    Undersown cover crop species introduced for weed management purposes should ideally combine adequate weed suppression with only marginal negative competitive effects on the main crop. The aim of this research was to identify the growth characteristics of clover species that determine weed

  4. Combining mechanical rhizome removal and cover crops for Elytrigia repens control in organic barley systems

    DEFF Research Database (Denmark)

    Melander, B; Nørremark, M; Kristensen, E F

    2013-01-01

    Mechanical weed control of perennial weeds in organic crop production over long post-harvest periods is incompatible with the establishment of cover crops for improving soil quality and preventing nutrient leaching. We suggest a new concept that comprises uprooting and immediate removal of vegeta...

  5. Annual and Perennial Alleyway Cover Crops Vary in Their Effects on Pratylenchus penetrans in Pacific Northwest Red Raspberry (Rubus idaeus).

    Science.gov (United States)

    Rudolph, Rachel E; Zasada, Inga A; DeVetter, Lisa W

    2017-12-01

    Cover crops can provide many benefits to agroecosystems, such as lessening soil erosion and increasing water infiltration. However, cover crop use is not common in established red raspberry ( Rubus idaeus ) fields in the Pacific Northwest. Raspberry growers are concerned about resource competition between the cover crop and raspberry crop, as well as increasing population densities of the plant-parasitic nematode Pratylenchus penetrans , which has a wide host range and has been shown to reduce raspberry plant vigor and yield. A 2-yr study was conducted in an established 'Meeker' raspberry field in northwest Washington to evaluate the effects of nine alleyway cover crops, mowed weed cover, and the industry standard of bare cultivated soil on P. penetrans population dynamics, raspberry yield, and fruit quality. The host status for P. penetrans of cover crops included in the field experiment, as well as Brassica juncea 'Pacific Gold' and Sinapis alba 'Ida Gold', was also evaluated in greenhouse experiments. In the field experiment, P. penetrans population densities did not increase in alleyway cover crop roots over time or in alleyway soil surrounding cover crop roots (means range from 0 to 116 P. penetrans /100 g of soil) compared with the bare cultivated control (means range from 2 to 55 P. penetrans /100 g of soil). Pratylenchus penetrans populations did not increase over time in raspberry grown adjacent to alleyways with cover crops (means range from 1,081 to 6,120 P. penetrans /g of root) compared with those grown adjacent to bare cultivated soil alleyways (means range from 2,391 to 5,536 P. penetrans /g of root). Raspberry grown adjacent to bare cultivated soil did not have significantly higher yield or fruit quality than raspberry grown adjacent to cover crops in either year of the experiment. In the greenhouse assays, 'Norwest 553' wheat and a perennial ryegrass mix were poor hosts for P. penetrans , whereas 'Nora' and 'TAM 606' oat and 'Pacific Gold' and 'Ida

  6. Nitrogen release from decomposing residues of leguminous cover crops and their effect on maize yield on depleted soils of Bukoba District, Tanzania

    NARCIS (Netherlands)

    Baijukya, F.P.; Ridder, de N.; Giller, K.E.

    2006-01-01

    Nitrogen release patterns from decomposing shoot residues of Tephrosia candida, Crotalaria grahamiana, Mucuna pruriens, Macrotyloma axillare, Macroptillium atropurpureum and Desmodium intortum were studied in the laboratory for a period of 22 weeks in a sandy clay soil and 10 weeks in a clay soil

  7. Vegetative, productive and qualitative performance of grapevine "Cabernet Sauvignon" according to the use of winter cover crops

    OpenAIRE

    Bettoni, Jean Carlos; Feldberg, Nelson Pires; Nava, Gilberto; Veiga, Milton da; Wildner, Leandro do Prado

    2016-01-01

    ABSTRACT To study the effect of winter cover crops on the vegetative, productive and qualitative behavior of "Cabernet Sauvignon" grapevines, an experiment was conducted in two wine harvests by sowing different species of winter cover crops and additional treatments with manual weeding and mechanical mowing in an experimental vineyard located at the Experimental Station of Epagri in Videira, state of Santa Catarina, Brazil. Plant attributes of the grapevine, such as number of rods and weight ...

  8. Nutrient cycling potential of camelina (Camelina sativa L. Crantz.) as a cover crop in the US Northern Great Plains

    Science.gov (United States)

    Berti, Marisol; Samarappuli, Dulan

    2017-04-01

    Camelina [Camelina sativa (L.) Crantz.] is an industrial oilseed crop in the Brassicaceae family with multiple uses. Currently, camelina is not used as a cover crop, but it has the potential to be used as such in maize-soybean-wheat cropping systems. The objectives of this study were to determine the agronomic performance and nutrient scavenging potential of winter camelina in comparison with other common cover crops. Experiments were conducted in Fargo, ND in 2015 and 2016, and in Prosper, ND in 2015. The experimental design was a randomized complete block design with a split-plot arrangement with three replicates. The main plot was the sowing date and the subplot were camelina cultivars as well as other common cover crops in the area. Sowing dates were targeted to 15 August and September 1, although the final dates varied slightly each year. Biomass yield, N content of the biomass N uptake and P uptake was evaluated. Winter camelina N and P uptake ranged between 21 and 30.5 kg N ha-1 and 3.4 to 5.3 kg P ha-1. The nutrient scavenging potential of winter camelina was similar to other cover crops although slightly lower than turnip (Brassica rapa L.), radish (Raphanus sativus L.), and rape (Brassica napus L.) cultivars which had significantly higher P uptake than winter camelina and the other cover crops in the study. An evaluation of spring regrowth and cover indicated that only rye, winter camelina, and pennycress (Thlaspi arvense L.) survived the winter, although a few plants of triticale (x Trticosecale Witt.) and rape were found on a few plots. Because of the high variability on the plots there were no significant differences among the surviving cover crops on soil coverage. The soil coverage for rye cultivars was 25 and 35% and for camelina cv. Bison was 27%.In 2016, biomass yield was not significant for sowing date, cultivars, or their interaction. Winter camelina cultivars biomass yield fluctuated between 1.15 and 2.33 Mg dry matter ha-1 on the first sowing

  9. Evaluation of Insecticides and Agril Polyester Cover against Whitefly (Bemisia Tabaci Gennadius in Tomato Crops

    Directory of Open Access Journals (Sweden)

    K.M. Azam

    1996-01-01

    Full Text Available Field experiments were conducted on tomato crops over a two year period to evaluate the efficacy of six insecticides, viz., triazophos, phosphamidon, dimethoate, buprofezin and Aflix (endosulfan + dimethoate each at 0.05% and Repelin (plant insecticide at 1% concentration along With a cultural treatment by covering the plants with Agril (a polyester material for the control of whitefly, Bemisia tabaci. The insecticides were applied eight times at weekly interval immediately after transplantation. The whitefly eggs,  nymphal population counts and the per cent incidence of tomato leaf curl virus (TLCV were recorded every week for eight weeks in all the treatments including untreated control. The incidence of whitefly was more severe in the second year (i.e, 1992-93 as compared to the previous season. Among the various treatments, the Agril cover, a newly introduced cultural practice, recorded the least incidence of whitefly and of TLCV. The average of counts of eggs were 0.0 and 5.47 and of nymphs 0.54 and 0.58 per 10 leaflets and TLCV were 4.32% and 4.76% in Agril cover treatment during the first and second year, respectively. Among the insecticides tested only Aflix recorded less incidence of the pest, being 3.46 and 30.4 eggs per 10 leaflets and 0.94 and 5.34 nymphs per 10 leaflets during the two years of study, respectively. The other treatments were less effective in reducing pest and disease incidence. The crop under Agril-cover recorded the maximum yield of 34.57 and 26.15 t/ha of tomatoes as compared to 16.48 and 10.82 t/ha in control during the first and second year, respectively.

  10. Effects of Cover Crop Species and Season on Population Dynamics of Escherichia coli and Listeria innocua in Soil

    Science.gov (United States)

    Reed-Jones, Neiunna L.; Marine, Sasha Cahn; Everts, Kathryne L.

    2016-01-01

    Cover crops provide several ecosystem services, but their impact on enteric bacterial survival remains unexplored. The influence of cover cropping on foodborne pathogen indicator bacteria was assessed in five cover crop/green manure systems: cereal rye, hairy vetch, crimson clover, hairy vetch-rye and crimson clover-rye mixtures, and bare ground. Cover crop plots were inoculated with Escherichia coli and Listeria innocua in the fall of 2013 and 2014 and tilled into the soil in the spring to form green manure. Soil samples were collected and the bacteria enumerated. Time was a factor for all bacterial populations studied in all fields (P innocua diminished somewhat but persisted, independently of season. In an organic field, the cover crop was a factor for E. coli in year 1 (P = 0.004) and for L. innocua in year 2 (P = 0.011). In year 1, E. coli levels were highest in the rye and hairy vetch-rye plots. In year 2, L. innocua levels were higher in hairy vetch-rye (P = 0.01) and hairy vetch (P = 0.03) plots than in the rye plot. Bacterial populations grew (P innocua numbers were observed after tilling (P innocua abundance in a transitional field (P < 0.05). Overall, the impacts of cover crops/green manures on bacterial population dynamics in soil varied, being influenced by bacterial species, time from inoculation, soil temperature, rainfall, and tillage; this reveals the need for long-term studies. PMID:26729724

  11. Impact of vetch cover crop on runoff, soil loss, soil chemical properties and yield of chickpea in North Gondar, Ethiopia

    Science.gov (United States)

    Demelash, Nigus; Klik, Andreas; Holzmann, Hubert; Ziadat, Feras; Strohmeier, Stefan; Bayu, Wondimu; Zucca, Claudio; Abera, Atikilt

    2016-04-01

    Cover crops improve the sustainability and quality of both natural system and agro ecosystem. In Gumara-Maksegnit watershed which is located in Lake Tana basin, farmers usually use fallow during the rainy season for the preceding chickpea production system. The fallowing period can lead to soil erosion and nutrient losses. A field experiment was conducted during growing seasons 2014 and 2015 to evaluate the effect of cover crops on runoff, soil loss, soil chemical properties and yield of chickpea in North Gondar, Ethiopia. The plot experiment contained four treatments arranged in Randomized Complete Block Design with three replications: 1) Control plot (Farmers' practice: fallowing- without cover crop), 2) Chickpea planted with Di-ammonium phosphate (DAP) fertilizer with 46 k ha-1 P2O5 and 23 k ha-1 nitrogen after harvesting vetch cover crop, 3) Chick pea planted with vetch cover crop incorporated with the soil as green manure without fertilizer, 4) Chick pea planted with vetch cover crop and incorporated with the soil as green manure and with 23 k ha-1 P2O5 and 12.5 k ha-1 nitrogen. Each plot with an area of 36 m² was equipped with a runoff monitoring system. Vetch (Vicia sativa L.) was planted as cover crop at the onset of the rain in June and used as green manure. The results of the experiment showed statistically significant (P plant, above ground biomass and grain yield of chick pea. However, there was no statistically significant difference (P > 0.05) on average plant height, average number of branches and hundred seed weight. Similarly, the results indicated that cover crop has a clear impact on runoff volume and sediment loss. Plots with vetch cover crop reduce the average runoff by 65% and the average soil loss decreased from 15.7 in the bare land plot to 8.6 t ha-1 with plots covered by vetch. In general, this result reveales that the cover crops, especially vetch, can be used to improve chickpea grain yield in addition to reduce soil erosion in the

  12. Effects of grass-clover management and cover crops on nitrogen cycling and nitrous oxide emissions in a stockless organic crop rotation

    DEFF Research Database (Denmark)

    Brozyna, Michal Adam; Petersen, Søren O; Chirinda, Ngoni

    2013-01-01

    Nitrogen (N) supply in stockless organic farming may be improved through use of grass-clover for anaerobic digestion, producing biogas and digested manure for use as fertilizer in the crop rotation. We studied the effects of grass-clover management on N cycling, nitrous oxide (N2O) emissions...... and cash-crop yields in an organic arable crop rotation on a sandy loam soil in a cool temperate climate. The four-course crop rotation included spring barley (with undersown grass-clover), grass-clover, potato and winter wheat (with undersown cover crop). Two fertilization treatments were compared: “−M...... in the rotation (spring barley, potato and winter wheat); actual digestion of grass-clover cuttings was not possible, instead digested pig manure was used as substitute for digested grass-clover. Nitrous oxide fluxes were monitored between April 2008 and May 2009. In general, application of digested manure had...

  13. 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

  14. The role of rabbit density and the diversity of weeds in the development of cover crops in olive groves

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero-Casado, J.; Carpio, A.J.; Prada, L.M.; Tortosa, F.S.

    2015-07-01

    Cover crops are an effective means to reduce soil erosion and to provide food and shelter for wildlife. However, in areas of intensive farming, which are characterised by the scarcity of weed communities, wild herbivores may focus their grazing on cover crops, which could make their implementation difficult. In this work, we test whether rabbit grazing can prevent the growth of herbaceous cover crops in olive groves in Southern Spain in addition to assessing the role of rabbit abundance and diversity of weeds in the development of cover crops. This question has been addressed by sowing Bromus rubens between the rows of five olive groves in Cordoba province (Spain). We then monitored the surface covered by B. rubens, along with both diversity of weed communities and rabbit abundance. Two rabbit exclusion areas were also placed in each olive grove in order to assess the impact of rabbits on the development of cover crops. Our results showed that the surface occupied by B. rubens was considerably higher in the rabbit exclusion areas (mean 56.8 ± 5.65 %) than in those areas in which they could feed (mean 35.6 ± 4.32 %). The coverage occupied by cover crops was higher in areas with lower rabbit density, although this relationship was modulated by the weed diversity index, since in areas with the same rabbit abundance the coverage was higher in those with a richer weed community. These findings suggest that high rabbit abundances can prevent the development of herbaceous cover crops in olive groves, particularly in areas in which alternative food resources (measured as weed diversity) are scarce. (Author)

  15. The role of rabbit density and the diversity of weeds in the development of cover crops in olive groves

    Directory of Open Access Journals (Sweden)

    José Guerrero-Casado

    2015-09-01

    Full Text Available Cover crops are an effective means to reduce soil erosion and to provide food and shelter for wildlife. However, in areas of intensive farming, which are characterised by the scarcity of weed communities, wild herbivores may focus their grazing on cover crops, which could make their implementation difficult. In this work, we test whether rabbit grazing can prevent the growth of herbaceous cover crops in olive groves in Southern Spain in addition to assessing the role of rabbit abundance and diversity of weeds in the development of cover crops. This question has been addressed by sowing Bromus rubens between the rows of five olive groves in Cordoba province (Spain. We then monitored the surface covered by B. rubens, along with both diversity of weed communities and rabbit abundance. Two rabbit exclusion areas were also placed in each olive grove in order to assess the impact of rabbits on the development of cover crops. Our results showed that the surface occupied by B. rubens was considerably higher in the rabbit exclusion areas (mean 56.8 ± 5.65 % than in those areas in which they could feed (mean 35.6 ± 4.32 %. The coverage occupied by cover crops was higher in areas with lower rabbit density, although this relationship was modulated by the weed diversity index, since in areas with the same rabbit abundance the coverage was higher in those with a richer weed community. These findings suggest that high rabbit abundances can prevent the development of herbaceous cover crops in olive groves, particularly in areas in which alternative food resources (measured as weed diversity are scarce.

  16. Green manuring effect of pure and mixed barley - hairy vetch winter cover crops on maize and processing tomato N nutrition

    DEFF Research Database (Denmark)

    Tosti, Giacomo; Benincasa, Paolo; Farneselli, Michela

    2012-01-01

    with the appropriate critical N dilution curves. The results highlight the effectiveness of mixtures for the management of the winter cover crop practice. In the two considered years, the species proportion influences the aboveground biomass (ranging from 2.90 to 5.94 Mg ha-1) and N accumulation (ranging from 73......Adopting mixtures between legumes and non legumes can be an efficient tool to merge the advantages of the single species in the fall-sown cover crop practice. Nevertheless there is a lack of information on how the species proportion may affect N accumulation and C/N of the cover crops and how...... this can influence the N uptake and N status of different subsequent summer cash crops. In this study the N effect of barley (Hordeum vulgare L.) and hairy vetch (Vicia villosa Roth.) grown in pure stands or in mixtures with different sowing proportion was tested on maize (Zea Mays L.) and processing...

  17. The kill date as a management tool for cover cropping success.

    Directory of Open Access Journals (Sweden)

    María Alonso-Ayuso

    Full Text Available Integrating cover crops (CC in rotations provides multiple ecological services, but it must be ensured that management does not increase pre-emptive competition with the subsequent crop. This experiment was conducted to study the effect of kill date on: (i CC growth and N content; (ii the chemical composition of residues; (iii soil inorganic N and potentially mineralizable N; and (iv soil water content. Treatments were fallow and a CC mixture of barley (Hordeum vulgare L. and vetch (Vicia sativa L. sown in October and killed on two different dates in spring. Above-ground biomass and chemical composition of CC were determined at harvest, and ground cover was monitored based on digital image analysis. Soil mineral N was determined before sowing and after killing the CC, and potentially mineralizable N was measured by aerobic incubation at the end of the experiment. Soil water content was monitored daily to a depth of 1.1 m using capacitance sensors. Under the present conditions of high N availability, delaying kill date increased barley above-ground biomass and N uptake from deep soil layers; little differences were observed in vetch. Postponing kill date increased the C/N ratio and the fiber content of plant residues. Ground cover reached >80% by the first kill date (∼1250°C days. Kill date was a means to control soil inorganic N by balancing the N retained in the residue and soil, and showed promise for mitigating N losses. The early kill date decreased the risk of water and N pre-emptive competition by reducing soil depletion, preserving rain harvested between kill dates and allowing more time for N release in spring. The soil potentially mineralizable N was enhanced by the CC and kill date delay. Therefore kill date is a crucial management variable for maximizing the CC benefits in agricultural systems.

  18. Weed infestation of spring barley (Hordeum vulgare L. depending on the cover crop and weed control method

    Directory of Open Access Journals (Sweden)

    Dorota Gawęda

    2014-04-01

    Full Text Available The aim of this 3-year field study was to evaluate the effect of some stubble crops and weed control methods on the species composition, number and air-dry weight of weeds in a spring barley crop grown in short-term monoculture. The study was conducted in the period 2009–2011 at the Uhrusk Experimental Farm, on mixed rendzina soil classified as very good rye soil complex. It included stubble crops which were ploughed under in each year (control treatment without cover crop, white mustard, lacy phacelia, a mixture of legumes – narrow-leaf lupin + field pea and 3 weed control methods used in spring barley crops (mechanical, mechanical and chemical, chemical weed control. Veronica persica was the weed species that occurred in greatest numbers in the spring barley crop sown after stubble crops. All cover crops reduced the numbers of Avena fatua which was the dominant species in the control treatment. Chemical as well as chemical and mechanical weed control significantly reduced the numbers of Avena fatua compared to the treatment where only double harrowing was used for weed control. The stubble crops did not reduce weed infestation of spring barley. Compared to the control treatment, the ploughing-in of white mustard and the mixture of legumes reduced the dry weight of weeds by 49.1 and 22.7%, respectively. Mechanical weed management proved to be less effective in reducing the number and dry weight of weeds compared to the other weed control methods. A significant negative correlation was found between the dry weight of weeds in the spring barley crop and the dry weight of the ploughed-in white mustard cover crop under the conditions of chemical weed control as well as in the case of the mixture of legumes when complete mechanical and chemical weed control was used.

  19. Eficácia de glyphosate em plantas de cobertura Efficacy of glyphosate in cover crops

    Directory of Open Access Journals (Sweden)

    P.C. Timossi

    2006-09-01

    Full Text Available Objetivou-se comparar a eficácia de três dosagens do herbicida glyphosate para a dessecação de Brachiaria decumbens, B. brizantha cv. Marandu e vegetação espontânea, visando a adoção do sistema plantio direto. Utilizou-se delineamento experimental de blocos ao acaso, num esquema fatorial 3 x 3, com quatro repetições. Testaram-se três tipos de cobertura vegetal e três dosagens de glyphosate (1,44, 2,16 e 2,88 kg ha-1. Aos 7, 14, 21 e 28 dias após a aplicação (DAA, foram feitas avaliações visuais da porcentagem de controle das coberturas vegetais e, aos 45 DAA, avaliações visuais da porcentagem de reinfestação da área. Conclui-se que, para as espécies que compunham a vegetação espontânea, o uso de 1,44 kg ha-1 proporcionou bom controle, sem no entanto evitar rebrotes de Digitaria insularis. Para as braquiárias, a mesma taxa de controle foi observada a partir de 2,16 kg ha-1. A camada de palha das braquiárias sobre o solo não foi capaz de suprimir a emergência de Cyperus rotundus, Alternanthera tenella, Raphanus raphanistrum, Bidens pilosa e Euphorbia heterophylla.This work aimed to compare rates of glyphosate to desiccate Brachiaria decumbens, B. brizantha cv. Marandu and spontaneous plants (weeds, aiming to adopt the no-tillage system. A randomized block experimental design in a factorial scheme was used (3x3, with four replications. The factors consisted of three species of cover crops and three rates of glyphosate (1.44, 2.16 and 2.88 kg ha-1. At 7, 14, 21 and 28 days after application of the herbicide, visual evaluations of the percentage of cover crop control were carried out and at 45 days of the reinfestation percentage of the area. It was concluded that the spontaneous plants presented a good control at 1.44 kg ha-1, without, however, preventing Digitaria insularis sprouts. The same control rate starting at 2.16 kg ha-1 was observed for the Brachiaria species. The straw layer of these cover crops on the soil

  20. Self-reseeding annual legumes for cover cropping in rainfed managed olive orchards

    Energy Technology Data Exchange (ETDEWEB)

    Ângelo Rodrigues, M.; Ferreira, I. Q.; Freitas, S.L.; Pires, J.M.; Arrobas, M.P.

    2015-07-01

    Given the environmental impact of nitrogen (N)-fertilizer manufacture and use, the sustainable management of agro-systems should be sought by growing N-fixing legumes. In this work, eleven self-reseeding annual legumes were grown in pure stands as mulching cover crops in a rainfed olive orchard managed without grazing animals. Dry matter yield, N content in above-ground biomass, groundcover percentage and persistence of the sown species were assessed during four growing seasons. All covers provided enough soil protection over the year, with living plants during the autumn/winter period and a mulch of dead residues during the summer. The legumes overcame a false break observed in the third year recovering the dominance of the covers in the fourth growing season. This means that the seed bank established in previous seasons ensured the persistence of the sown legume even when a gap in seed production occurred. The early-maturing cultivars produced less biomass and fixed less N (approx. 50 kg N/ha/yr present in the above-ground biomass) than the late-maturing ones, but would compete less for water since the growing cycle finished earlier in the spring. They seem best suited to being grown in dry farmed olive orchards with low N demand in drought prone regions. (Author)

  1. Influence of cover crops and crop residue treatment on soil organic carbon stocks evaluated in Swedish long-term field experiments

    Science.gov (United States)

    Poeplau, Christopher; Bolinder, Martin A.; Börjesson, Gunnar; Kätterer, Thomas

    2015-04-01

    Soil organic carbon (SOC) stocks in agricultural soils are strongly controlled by management. In this study we quantified the effect of cover crops and crop residue management on SOC stocks in Swedish long-term experiments. Eight pairs of cover crop (undersown ryegrass) vs. no cover crop were investigated in Swedish long-term field experiments (16 to 24 years). Yields of the main crop were not affected by the cover crop. Cover crops significantly increased SOC stocks, with a mean carbon sequestration rate in all experiments (excluding one) of 0.32±0.29 Mg C ha-1 yr-1. Interestingly, this sequestration is similar to that estimated for a U.S.experiment, where ryegrass growth is much less temperature- and light-limited than under Swedish conditions. This sequestration rate is also the same as that recently reported for many other cover crops in a global meta-analysis but less than SOC changes in ley-dominated rotations which under Nordic conditions were shown to accumulate in average 0.5 Mg C ha-1 yr-1 more carbon compared to exclusively annual cropping systems. Thus, originally introduced in agricultural rotations to reduce nitrate leaching, cover crops are also an effective practice to increase SOC stocks, even at relatively high latitudes. The effect of crop residue treatment was studied in 16 pairs of straw incorporated (SI) vs. straw removed (SR) treatments in six Swedish long-term field experiments. Data series on SOC with 5-28 sampling dates during 27-53 years were analysed using ICBM, a dynamic SOC model. At five out of six sites, the humification coefficient for straw (hlitter; the fraction of straw C that is entering the slow C pool) was much smaller (0-0.09) than the ICBM default h-value for plant material estimated in previous studies (0.125). The derived hlitter-values and thus the stabilization of straw-derived carbon increased significantly with clay content. For an Italian site (with five pairs of SI vs. SR) that was used for model validation we found

  2. [Intake of leguminous in the Department of Santander, Colombia, 2000-2003].

    Science.gov (United States)

    Prada, Gloria E; Soto, Adriana; Herrán, Oscar F

    2005-03-01

    With the objective of describing the participation and quantity (g) in the intake of leguminous in two geographical areas (metropolitan and rural), three surveys were re-analyzed, in them 571 subjects (148 scholars and 443 mothers) described their intake by the 24-hour dietary recall method. For the above mentioned, descriptive measures and confidence intervals were calculated with a reliability of 95% (IC 95%), the comparison of the intake among groups was carried out by t test and analysis of variance. 36.4% of the subjects consumes leguminous dry; differences were observed in the consumption of leguminous for geographical area; leguminous dry (p = 0.03) and green (p = 0.04). Of the group of leguminous, the dry ones represent the best resource to cover the energy necessities and nutritious; the biggest contribution to the daily recommendation is for folic acid, magnesium, thiamine, protein, phosphorus, iron and zinc. The contribution of the leguminous ones to the recommendations of nutrients was different for geographical area (p leguminous dry, especially to the daily recommendations of folic acid and proteins are aspects to consider in their promotion.

  3. Cover crops influence soil microorganisms and phytoextraction of copper from a moderately contaminated vineyard.

    Science.gov (United States)

    Mackie, K A; Schmidt, H P; Müller, T; Kandeler, E

    2014-12-01

    We investigated the ability of summer (Avena sativa [oat], Trifolium incarnatum [crimson clover], Chenopodium [goosefoot]) and winter (Vicia villosa [hairy vetch], Secale Cereale L. [Rye], Brassica napus L. partim [rape]) cover crops, including a mixed species treatment, to extract copper from an organic vineyard soil in situ and the microbial communities that may support it. Clover had the highest copper content (14.3mgCukg(-1) DM). However, it was the amount of total biomass production that determined which species was most effective at overall copper removal per hectare. The winter crop rye produced significantly higher amounts of biomass (3532kgDMha(-1)) and, therefore, removed significantly higher amounts of copper (14,920mgCuha(-1)), despite less accumulation of copper in plant shoots. The maximum annual removal rate, a summation of best performing summer and winter crops, would be 0.033kgCuha(-1)y(-1). Due to this low annual extraction efficiency, which is less than the 6kgCuha(-1)y(-1) permitted for application, phytoextraction cannot be recommended as a general method of copper extraction from vineyards. Copper concentration did not influence aboveground or belowground properties, as indicated by sampling at two distances from the grapevine row with different soil copper concentrations. Soil microorganisms may have become tolerant to the copper levels at this site. Microbial biomass and soil enzyme activities (arylsulfatase and phosphatase) were instead driven by seasonal fluxes of resource pools. Gram+ bacteria were associated with high soil moisture, while fungi seemed to be driven by extractable carbon, which was linked to high plant biomass. There was no microbial group associated with the increased phytoextraction of copper. Moreover, treatment did not influence the abundance, activity or community structure of soil microorganisms. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Tillage systems and cover crops on soil physical properties after soybean cultivation

    Directory of Open Access Journals (Sweden)

    Rafael B. Teixeira

    Full Text Available ABSTRACT Soil management alters soil physical attributes and may affect crop yield. In order to evaluate soil physical attributes in layers from 0 to 0.40 m and soybean grain yield, in the 2012/2013 agricultural year, an essay was installed in the experimental area of the Federal University of Mato Grosso do Sul (UFMS/CPCS. Soil tillage systems were: conventional tillage (CT, minimum tillage (MT and no tillage (DS, the cover crops used were millet, sunn hemp and fallow. The experimental design was randomized blocks with split plots. For the layer of 0.20-0.30 m, millet provided the best results for soil bulk density, macro and microporosity. The resistance to penetration (RP was influenced in the layer of 0-0.10 m, and millet provided lower RP. The DS provided the lowest RP values for the layer of 0.10-0.20 m. The treatments did not influence yield or thousand-seed weight.

  5. Impact of cover crops in vineyard on the aroma compounds of Vitis vinifera L. cv Cabernet Sauvignon wine.

    Science.gov (United States)

    Xi, Zhu-Mei; Tao, Yong-Sheng; Zhang, Li; Li, Hua

    2011-07-15

    This study compared the influence of different cover crops with clean tillage on wine aroma compounds of 5-year-old Cabernet Sauvignon vines. White clover, alfalfa, and tall fescue were used in the vineyard and compared with clean tillage. Aroma compounds of wine were analysed by solid-phase microextraction gas chromatography-mass spectrometry (SPME-GC/MS). Forty-seven volatile compounds were identified and quantified. Wines made from grapes grown with various cover crops had higher levels of aroma compounds. Ethyl acetate, isoamyl acetate, ethyl octanoate, ethyl hexanoate, phenylethyl acetate, isoamyl alcohol, linalool, citronellol, β-damascenone, α-ionone, and 5-amyl-dihydro-2(3H)-furan were the impact odorants of sample wines. Wines from cover crop also had higher contents of these impact odorants than the control. For different cover crops, alfalfa sward yielded the highest levels, followed by the tall fescue treatment. According to the data analysis of aroma compounds and sensory assess, permanent cover crop may have the potential to improve wine quality. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  6. Effect of the different cover crops on the soil moisture in a Hungarian vineyard

    Science.gov (United States)

    Donkó, Ádám; Miglécz, Tamás; Valkó, Orsolya; Deák, Balázs; Kelemen, András; Török, Péter; Tóthmérész, Béla; Drexler, Dóra

    2017-04-01

    Since many years it is well known that the one-sided mechanical soil cultivation of vineyard inter-rows has many disadvantages. Growers can choose from alternative tillage technologies, such as the usage of green manure, or covering the inter-rows with straw mulch. Another possible technology is tto cover the inter-rows with species-rich seed mixtures. However, selection of the most suitable species is crucial; we have to take into consideration the age of the vines, and the specific characteristics of the vineyards involved. Species rich cover crop technology has many advantages: 1) it helps to prevent erosion and creates easier cultivation circumstances, 2) it has a positive effect on soil structure, soil fertility and ecosystem services, 3) we can create native mixtures from local provenance, adapted to the local climate/vine region/vineyard which enhances the nature conservation value of our site. But, they should not compete significantly with the grapevines, or negatively influence produce quality. In the year of 2012 we created, and started to study three different cover-crop mixtures in Hungarian wine regions under on-farm conditions: Biocont-Ecovin mixture, Mixture of Legumes, Mixture of Grass and Herbs. The results of the botanical surveys, yield and pruning weight were published in many papers and presentations before (e.g. Miglécz et al. 2015, Donkó et al. 2016). Besides the above measures, one key point of the effectiveness and sustainability of the living mulch vegetation is the level of soil moisture. That is why we started to investigate the soil moisture (vol %) of different treatments (Biocont-Ecovin mixture, Mixture of Legumes, Mixture of Grass and Herbs, coverage with Lolium perenne, and Control (spontaneous weed flora)) in at the Feind Winery in Balatonfőkajár (Hungary). The investigated variety is Welschriesling on loamy soil (Tihany Formation), planted in 2010. The seed mixtures were sown in the spring of 2013. We measured soil moisture

  7. Cover-crops - improvement of soil fertility and provision of biomass

    Science.gov (United States)

    Kirchmeyr, Franz; Szerencsits, Manfred

    2017-04-01

    Besides climate change, erosion, inadequate crop rotation and intensive tillage may turn arable land into marginal land. On the other hand, reclamation approaches which include arable farming methods may result only in short-term success if they do not consider their effects on humus content and erosion. Additionally, effective reclamation will also have to address the growing need for food production besides biomass provision. Therefore, we investigated if cover or catch crops (CC) may accomplish both goals: Improve soil quality and humus content even if CC-biomass is used for biogas production. Humus content and soil fertility: In comparison to complete fallow in a crop rotation with silage maize and cereals the humus balance can be improved from -50 to +280 kg humus carbon (C) ha-1 year-1 through additional CC (4.5 t DM ha-1) used for biogas production and an equivalent amount of digestate returned to the field. With a CC-yield of 2.5 t DM ha-1 the humus balance results in 220 kg C ha-1 year-1. It is still slightly higher if the same CC remains on the field as green manure (170 kg C ha-1 year-1). Additionally it is important to consider that 20 - 50 % of the assimilated carbon can be found in the plant roots and that roots and root exudates as well as CC harvest residues provide fresh organic matter for soil life. Furthermore, biomass production of cover crops was considerably higher, if they were used for biogas production because of earlier cultivation and later harvest than mulching. Erosion control: The risk of erosion can be reduced by approx. 50 % in comparison to complete fallow if CC with 2.5 t DM ha-1 remain on the field as green manure. A comparable reduction can be achieved, if CC with 4.5 t DM ha-1 are harvested for biogas production. Because of better weed suppression, tilth and soil structure of CC with higher biomass, it is more likely to apply conservation tillage and avoid ploughing. Without ploughing a CC with 4.5 t DM ha-1 used for biogas the

  8. COVER CROPS EFFECTS ON THE DEVELOPMENT OF UPLAND RICE UNDER ORGANIC FARMING SYSTEM PLANTAS DE COBERTURA DE SOLO E SEUS EFEITOS NO DESENVOLVIMENTO DA CULTURA DO ARROZ DE TERRAS ALTAS EM CULTIVO ORGÂNICO

    Directory of Open Access Journals (Sweden)

    Roberta Paula de Jesus

    2007-12-01

    Full Text Available

    This research was conducted in an experimental area in Santo Antônio de Goiás (16º28'S, 49º17'W and altitude 823 m, Brazil, during the months of June, 2004, and March, 2005. The upland rice variety Aimoré was used along with several cover crops aiming to evaluate leaf area, number of tillers, dry matter, and nitrogen content in the phytomass during the rice crop cycle. The experimental design was the randomized blocks one, with five treatments and four replications. The treatments consisted of different cover crops, such as velvet bean (Mucuna aterrima, sunn hemp (Crotalaria juncea, dwarf pigeon pea (Cajanus cajan, broom sorghum (Sorghun bicolor, and a check treatment with spontaneous vegetation growing among the rice plants. The leguminous plants, specially C. juncea, presented better results in tillering production, leaf area index, dry matter yield, and accumulated nitrogen content, if compared to the treatments where grasses were used as soil cover crop. It was concluded that rice presented a satisfactory development in the different soil cover treatments, specially after leguminous cultivation.

    KEY-WORDS: Rice, green manure, leaf area index, dry matter.

    O experimento foi conduzido numa área experimental em Santo Antônio de Goiás (16º28'S, 49º17'W e altitude de 823 m, no período de junho de 2004 a março de 2005. Utilizou-se a cultivar Aimoré de arroz de terras altas, em seqüência a diferentes plantas de cobertura de solo, com o objetivo de avaliar o índice de área foliar (IAF, número de afilhos, acúmulo de massa de matéria seca (MMS e o teor de nitrogênio acumulado na fitomassa durante o ciclo da cultura do arroz. O delineamento experimental foi o de blocos ao acaso, com cinco

  9. Comportamento de dois genótipos de milho cultivados em sistema de aléias preestabelecido com diferentes leguminosas arbóreas Behaviour of two maize genotypes grown in alley cropping system pre-established with diferents leguminous trees

    Directory of Open Access Journals (Sweden)

    Andréia Araújo Lima Leite

    2008-12-01

    feasibility of maize crop in a leguminous tree alley cropping. A random block experimental design was adopted, with four replicates and five treatments: alleys of "sombreiro" (Clitoria fairchildiana, inga (Inga edulis, pigeon pea (Cajanus cajan, and leucaena (Leucaena leucocephala and a control treatment without alley. C and N partitioning, grain yield, 1000 grain mass and interspecifics competition between maize varieties and legume hedgerows were evaluated. Grain yield was higher for C. fairchildiana and L. leucocephala treatments. The grain yield of hibrid maize was higher than that of maize variety at all treatments. The grain yield and 1000 grain mass maize was not affected by distance of legume hedgerows. This study concluded that the alley cropping with leguminous tree is an important alternative to the sustainable management of agroecosystems in humid tropics. Furthermore, in this region, the productivity of maize grain is favored in alley cropping with leguminous trees, like sombreiro, inga and leucena by genotypes efficient in the use of nitrogen, whose timing between its release and absorption when applied by means of pulses, must be enhanced.

  10. How Reliable is the MODIS Land Cover Product for Crop Mapping Sub-Saharan Agricultural Landscapes?

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    Louise Leroux

    2014-09-01

    Full Text Available Accurate cropland maps at the global and local scales are crucial for scientists, government and nongovernment agencies, farmers and other stakeholders, particularly in food-insecure regions, such as Sub-Saharan Africa. In this study, we aim to qualify the crop classes of the MODIS Land Cover Product (LCP in Sub-Saharan Africa using FAO (Food and Agricultural Organisation and AGRHYMET (AGRiculture, Hydrology and METeorology statistical data of agriculture and a sample of 55 very-high-resolution images. In terms of cropland acreage and dynamics, we found that the correlation between the statistical data and MODIS LCP decreases when we localize the spatial scale (from R2 = 0.86 *** at the national scale to R2 = 0.26 *** at two levels below the national scale. In terms of the cropland spatial distribution, our findings indicate a strong relationship between the user accuracy and the fragmentation of the agricultural landscape, as measured by the MODIS LCP; the accuracy decreases as the crop fraction increases. In addition, thanks to the Pareto boundary method, we were able to isolate and quantify the part of the MODIS classification error that could be directly linked to the performance of the adopted classification algorithm. Finally, based on these results, (i a regional map of the MODIS LCP user accuracy estimates for cropland classes was produced for the entire Sub-Saharan region; this map presents a better accuracy in the western part of the region (43%–70% compared to the eastern part (17%–43%; (ii Theoretical user and producer accuracies for a given set of spatial resolutions were provided; the simulated future Sentinel-2 system would provide theoretical 99% user and producer accuracies given the landscape pattern of the region.

  11. Impact of climate change on water balance components in Mediterranean rainfed olive orchards under tillage or cover crop soil management

    Science.gov (United States)

    Rodríguez-Carretero, María Teresa; Lorite, Ignacio J.; Ruiz-Ramos, Margarita; Dosio, Alessandro; Gómez, José A.

    2013-04-01

    The rainfed olive orchards in Southern Spain constitute the main socioeconomic system of the Mediterranean Spanish agriculture. These systems have an elevated level of complexity and require the accurate characterization of crop, climate and soil components for a correct management. It is common the inclusion of cover crops (usually winter cereals or natural cover) intercalated between the olive rows in order to reduce water erosion. Saving limited available water requires specific management, mowing or killing these cover crops in early spring. Thus, under the semi-arid conditions in Southern Spain the management of the cover crops in rainfed olive orchards is essential to avoid a severe impact to the olive orchards yield through depletion of soil water. In order to characterize this agricultural system, a complete water balance model has been developed, calibrated and validated for the semi-arid conditions of Southern Spain, called WABOL (Abazi et al., 2013). In this complex and fragile system, the climate change constitutes a huge threat for its sustainability, currently limited by the availability of water resources, and its forecasted reduction for Mediterranean environments in Southern Spain. The objective of this study was to simulate the impact of climate change on the different components of the water balance in these representative double cropping systems: transpiration of the olive orchard and cover crop, runoff, deep percolation and soil water content. Four climatic scenarios from the FP6 European Project ENSEMBLES were first bias corrected for temperatures and precipitation (Dosio and Paruolo, 2011; Dosio et al., 2012) and, subsequently, used as inputs for the WABOL model for five olive orchard fields located in Southern Spain under different conditions of crop, climate, soils and management, in order to consider as much as possible of the variability detected in the Spanish olive orchards. The first results indicate the significant effect of the cover

  12. Modeled Impacts of Cover Crops and Vegetative Barriers on Corn Stover Availability and Soil Quality

    Energy Technology Data Exchange (ETDEWEB)

    Ian J. Bonner; David J. Muth Jr.; Joshua B. Koch; Douglas L. Karlen

    2014-06-01

    Environmentally benign, economically viable, and socially acceptable agronomic strategies are needed to launch a sustainable lignocellulosic biofuel industry. Our objective was to demonstrate a landscape planning process that can ensure adequate supplies of corn (Zea mays L.) stover feedstock while protecting and improving soil quality. The Landscape Environmental Assessment Framework (LEAF) was used to develop land use strategies that were then scaled up for five U.S. Corn Belt states (Nebraska, Iowa, Illinois, Indiana, and Minnesota) to illustrate the impact that could be achieved. Our results show an annual sustainable stover supply of 194 million Mg without exceeding soil erosion T values or depleting soil organic carbon [i.e., soil conditioning index (SCI)?>?0] when no-till, winter cover crop, and vegetative barriers were incorporated into the landscape. A second, more rigorous conservation target was set to enhance soil quality while sustainably harvesting stover. By requiring erosion to be <1/2 T and the SCI-organic matter (OM) subfactor to be >?0, the annual sustainable quantity of harvestable stover dropped to148 million Mg. Examining removal rates by state and soil resource showed that soil capability class and slope generally determined the effectiveness of the three conservation practices and the resulting sustainable harvest rate. This emphasizes that sustainable biomass harvest must be based on subfield management decisions to ensure soil resources are conserved or enhanced, while providing sufficient biomass feedstock to support the economic growth of bioenergy enterprises.

  13. Can cover crops pull double duty: Conservation and profitable forage production in the Midwestern U.S.?

    Science.gov (United States)

    Data from a recent survey suggests that the major reasons Nebraska farmer’s plant cover crops are to: improve soil organic matter, reduce erosion, improve soil water holding capacity, produce forage, and increase soil microbial biomass. Many of these benefits appear to be positively correlated with...

  14. Vegetative, productive and qualitative performance of grapevine "Cabernet Sauvignon" according to the use of winter cover crops

    Directory of Open Access Journals (Sweden)

    Jean Carlos Bettoni

    Full Text Available ABSTRACT To study the effect of winter cover crops on the vegetative, productive and qualitative behavior of "Cabernet Sauvignon" grapevines, an experiment was conducted in two wine harvests by sowing different species of winter cover crops and additional treatments with manual weeding and mechanical mowing in an experimental vineyard located at the Experimental Station of Epagri in Videira, state of Santa Catarina, Brazil. Plant attributes of the grapevine, such as number of rods and weight of pruned material and number of branches per plant. At the time of skin color change, petioles of recently matured leaves were collected for analysis of the levels of N, P, K, Ca, Mg, Fe, Mn, Zn and B. Moments before harvest, 100 grape berries were collected randomly to determine the total soluble solids, titratable acidity and pH. At harvest, the number of bunches per branch, the number and mass of clusters per plant and the average mass of clusters per plot were determined. Fresh and dry matter yields of the cover crop and weed plants were also determined when coverage reached full bloom. The winter cover crops did not alter the yield and quality of "Cabernet Sauvignon" grapes and showed no differences from each other for the management of spontaneous vegetation by hand weeding or mechanical mowing. Rye and ryegrass are effective alternatives for weed control alternatives. The species of white and red clover present difficulty in initial establishment, producing a small amount of biomass.

  15. Effects of terminating cover crops with rolling/crimping and herbicides in a cotton no-till system

    Science.gov (United States)

    In fall of 2008, a field experiment was initiated in central Alabama to study the effects of rolling/crimping and different herbicides with different application rates on cover crops termination rates, cotton population and yield. Results from 2009 and 2010 growing seasons are presented. A roller/cr...

  16. Weed control in organic rice using plastic mulch and water seeding methods in addition to cover crops

    Science.gov (United States)

    Weeds are a major yield limiting factor in organic rice farming and are more problematic than in conventional production systems. Water seeding is a common method of reducing weed pressure in rice fields as many weeds connot tolerate flooded field conditions. The use of cover crops is another method...

  17. Coberturas vegetais no desenvolvimento vegetativo de plantas de pessegueiro Crop covers in the vegetative development of peach trees

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    Leo Rufato

    2007-04-01

    Full Text Available A utilização de cultivos de cobertura em pomares de pessegueiro no Brasil ainda é pouco difundida, apesar de haver diversas espécies de cobertura vegetal com potencial para tanto. Neste trabalho, estudaram-se os efeitos da a utilização de cinco espécies de plantas para cobertura vegetal de inverno: aveia-preta, chícharo, ervilha forrageira; nabo forrageiro; tremoço-azul, quatro consorciações entre elas e mais a testemunha, com vegetação espontânea sobre o desenvolvimento vegetativo de plantas de pessegueiro cv. Maciel sobre capedeboscq. Todas as espécies vegetais avaliadas adaptaram-se como cobertura vegetal nas condições edafoclimáticas da região Sul do Rio Grande do Sul. As coberturas vegetais, com exceção, sobretudo, do nabo forrageiro, incrementaram o desenvolvimento das plantas de pessegueiro.The use of the crop covers in Brazilian peach orchards is still not so spread, though there are several species of crop covers with the potential have the effect studied. This research presents the effects of the five plant species use for winter vegetal crop covers: Avena strigosa, Lathyrus sativus, Pisum sativum subesp. arvense, Raphanus sativus var. oleiferus, Lupinus angustifolius, four combinations among these species and the control treatments (native vegetation, with spontaneous vegetationon the vegetative development of "Maciel" peach tree under Capdeboscq rootstock. All of the crop covers evaluated adapted themselves to the soil and climate conditions of the south of "Rio Grande do Sul'. The crop covers, except the Raphanus sativus var. oleiferus, increased positively the phenological and vegetative development of peach trees; the Lupinus angustifolius also increased the phenological and vegetative development of plants.

  18. Peculiarities in covering the requirements for seed material of sorghum crops

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    С. І. Мельник

    2017-12-01

    Full Text Available Purpose. To assess the demand for sorghum seed material and sufficiency of domestic seeds. Results. The analysis of the State register for the period of 2002–2012 showed that there was the tendency not only towards increasing quantity of sorghum crops in general but their substitution by hybrids of foreign breeding. During the period from 2002 to 2017, 72 sorghum varieties were entered on the State register in total, among them only 12 varieties were of domestic breeding, the rest 60 was presented by foreign breeding institutions. Investigation results allowed to determine that the production of base and prebase seeds of sorghum in 2010 amounted to 1,3 t, in 2016 was 43 t. During the same period the production of sugar sorghum increased from 0,2 to 12,0 t, grass sorghum – from 4,0 to 83 t. In 2017, requirements of acreage of such crops as grass sorghum and broomcorn were completely satisfied by the amount of grown seeds. At the same time, the need for seeds of sorghum and sugar sorghum can not be covered completely at the expense of domestic varieties reproduction. In 2017, general demand for sorghum seeds was 400,5 t, among which only 42,0 t was of domestic production. The rest demand for seeds will be met at the expense of import of foreign breeding seeds into the country to be grown and prepared for sowing abroad. Conclusions. In the Register of plant varieties suitable for dissemination in Ukraine, there are 72 sorghum varieties among them only 12 varieties were of domestic breeding, that is 17%, as compared to 83% of recommended great sorghum varieties of foreign breeding. In Ukraine, the area occupied by sorghum cultivation was 22,8 thou ha in 2005, up to 2017 it increased to 89,0 thou ha, and accordingly the demand for seeds run up from 102,6 to 400,5 t. The area occupied by the sugar sorghum in 2005 amounted to only 2,6 thou ha, in 2017 – 20,0 thou ha, that accordingly determined increase of demand for seed material from 13,0 to 99

  19. Allelopathic effects of two cover crops Commelina diffusa Burm. F. and Tradescantia zebrina Shunltz on Coffea arabica L.

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    Georgina Berroa Navarro

    2016-03-01

    Full Text Available Allelopathic effect of the cover crops Tradescantia zebrina Shunltz (cucaracha and Commelina diffusa Burm. F. (canutillo were evaluated on Coffea arabica Lin. seeds Caturra Rojo variety. Germination tests were carried out “in vitro” and it was evaluated the root longitude, percentage of total germination and period of germination, as well as the height of the plant and the emergency percentage for the incorporation tests to the soil. It was also carried out, to both over crops, the preliminary chemical qualitative characterization. The results showed that the extracts of T. zebrina and of C. diffusa stimulated the “in vitro” germination and growth of C. arabica at different concentration levels. The incorporation to the soil of the extracts of C. diffusa stimulated the development of the plants of C. arabica, in a significant way, that supposes a considerable advantage in that concerns to the employment of these cover crops, when not implying noxious effects beside all the benefits implied when using cover crops. These last ones go from the protection and improvement of the properties of the soil, to the control of the spontaneous flora in the coffee agroecosystems.

  20. Weed Flora and Dormant-season cover crops have no effects on arbuscular mycorrhizae of grapevine

    Science.gov (United States)

    We tested the hypotheses that mycorrhizal colonization of a perennial crop increases with a high frequency of mycorrhizal hosts within the plant community, and that a high diversity of mycorrhizal hosts is associated with a high diversity of arbuscular mycorrhizal fungi (AMF) on the perennial crop. ...

  1. Long-term use of cover crops and no-till shift soil microbial community life strategies in agricultural soil.

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    Radomir Schmidt

    Full Text Available Reducing tillage and growing cover crops, widely recommended practices for boosting soil health, have major impacts on soil communities. Surprisingly little is known about their impacts on soil microbial functional diversity, and especially so in irrigated Mediterranean ecosystems. In long-term experimental plots at the West Side Research and Extension Center in California's Central Valley, we characterized soil microbial communities in the presence or absence of physical disturbance due to tillage, in the presence or absence of cover crops, and at three depths: 0-5, 5-15 and 15-30 cm. This characterization included qPCR for bacterial and archaeal abundances, DNA sequencing of the 16S rRNA gene, and phylogenetic estimation of two ecologically important microbial traits (rRNA gene copy number and genome size. Total (bacterial + archaeal diversity was higher in no-till than standard till; diversity increased with depth in no-till but decreased with depth in standard till. Total bacterial numbers were higher in cover cropped plots at all depths, while no-till treatments showed higher numbers in 0-5 cm but lower numbers at lower depths compared to standard tillage. Trait estimates suggested that different farming practices and depths favored distinctly different microbial life strategies. Tillage in the absence of cover crops shifted microbial communities towards fast growing competitors, while no-till shifted them toward slow growing stress tolerators. Across all treatment combinations, increasing depth resulted in a shift towards stress tolerators. Cover crops shifted the communities towards ruderals-organisms with wider metabolic capacities and moderate rates of growth. Overall, our results are consistent with decreasing nutrient availability with soil depth and under no-till treatments, bursts of nutrient availability and niche homogenization under standard tillage, and increases in C supply and variety provided by cover crops. Understanding how

  2. Long-term use of cover crops and no-till shift soil microbial community life strategies in agricultural soil.

    Science.gov (United States)

    Schmidt, Radomir; Gravuer, Kelly; Bossange, Anne V; Mitchell, Jeffrey; Scow, Kate

    2018-01-01

    Reducing tillage and growing cover crops, widely recommended practices for boosting soil health, have major impacts on soil communities. Surprisingly little is known about their impacts on soil microbial functional diversity, and especially so in irrigated Mediterranean ecosystems. In long-term experimental plots at the West Side Research and Extension Center in California's Central Valley, we characterized soil microbial communities in the presence or absence of physical disturbance due to tillage, in the presence or absence of cover crops, and at three depths: 0-5, 5-15 and 15-30 cm. This characterization included qPCR for bacterial and archaeal abundances, DNA sequencing of the 16S rRNA gene, and phylogenetic estimation of two ecologically important microbial traits (rRNA gene copy number and genome size). Total (bacterial + archaeal) diversity was higher in no-till than standard till; diversity increased with depth in no-till but decreased with depth in standard till. Total bacterial numbers were higher in cover cropped plots at all depths, while no-till treatments showed higher numbers in 0-5 cm but lower numbers at lower depths compared to standard tillage. Trait estimates suggested that different farming practices and depths favored distinctly different microbial life strategies. Tillage in the absence of cover crops shifted microbial communities towards fast growing competitors, while no-till shifted them toward slow growing stress tolerators. Across all treatment combinations, increasing depth resulted in a shift towards stress tolerators. Cover crops shifted the communities towards ruderals-organisms with wider metabolic capacities and moderate rates of growth. Overall, our results are consistent with decreasing nutrient availability with soil depth and under no-till treatments, bursts of nutrient availability and niche homogenization under standard tillage, and increases in C supply and variety provided by cover crops. Understanding how agricultural

  3. Organic weed conrol and cover crop residue integration impacts on weed control, quality, and yield and economics in conservation tillage tomato - A case study

    Science.gov (United States)

    The increased use of conservation tillage in vegetable production requires more information be developed on the role of cover crops in weed control, tomato quality and yield. Three conservation-tillage systems utilizing crimson clover, brassica and cereal rye as winter cover crops were compared to ...

  4. Sensitivity of crop cover to climate variability: insights from two Indian agro-ecoregions.

    Science.gov (United States)

    Mondal, Pinki; Jain, Meha; DeFries, Ruth S; Galford, Gillian L; Small, Christopher

    2015-01-15

    Crop productivity in India varies greatly with inter-annual climate variability and is highly dependent on monsoon rainfall and temperature. The sensitivity of yields to future climate variability varies with crop type, access to irrigation and other biophysical and socio-economic factors. To better understand sensitivities to future climate, this study focuses on agro-ecological subregions in Central and Western India that span a range of crops, irrigation, biophysical conditions and socioeconomic characteristics. Climate variability is derived from remotely-sensed data products, Tropical Rainfall Measuring Mission (TRMM - precipitation) and Moderate Resolution Imaging Spectroradiometer (MODIS - temperature). We examined green-leaf phenologies as proxy for crop productivity using the MODIS Enhanced Vegetation Index (EVI) from 2000 to 2012. Using both monsoon and winter growing seasons, we assessed phenological sensitivity to inter-annual variability in precipitation and temperature patterns. Inter-annual EVI phenology anomalies ranged from -25% to 25%, with some highly anomalous values up to 200%. Monsoon crop phenology in the Central India site is highly sensitive to climate, especially the timing of the start and end of the monsoon and intensity of precipitation. In the Western India site, monsoon crop phenology is less sensitive to precipitation variability, yet shows considerable fluctuations in monsoon crop productivity across the years. Temperature is critically important for winter productivity across a range of crop and management types, such that irrigation might not provide a sufficient buffer against projected temperature increases. Better access to weather information and usage of climate-resilient crop types would play pivotal role in maintaining future productivity. Effective strategies to adapt to projected climate changes in the coming decades would also need to be tailored to regional biophysical and socio-economic conditions. Copyright © 2014

  5. Productivity and Utilization of Leguminous Tree Indigofera zollingeriana on Dry Land

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    Iwan Herdiawan

    2014-06-01

    Full Text Available Indigofera is well known as tarum plant, has about 700 species, including Indigofera zollingeriana. These plants are leguminous species that have high nutrient content and production as well as tolerant to abiotic stresses. This plant originated in tropical Africa, Asia, Australia, and North and South America, then spread to arid zone of Africa and Asia. In early 1900, it was brought by Europeans colonial to Indonesia. Indigofera can grow well at altitudes between 0-2200 m above sea level, with rainfall between 600-3000 mm/year. It can be used as a fodder crop because it has high nutrient content and production. It can be harvested at the age of eight months with an average production of 2,595 kg of fresh biomass/tree, with a total production of fresh approximately 52 tons/ha. Indigofera zollingeriana has crude protein content of 27.60%; neutral detergent fiber (NDF 43.56%; acid detergent fiber (ADF 35.24%; calcium (Ca 1.16%; phosphorous (P 0.26%; in vitro-dry matter digestibility (IVDMD 67.50%; organic matter digestibility (IVOMD 60.32%; 0.08% tannins and 0.41% saponin. Additionally I. zollingeriana is often used as green manure, cover crop in plantation areas, fabric dyeing and therapeutic herbs.

  6. Suitability of peanut residue as a nitrogen source for a rye cover crop Resíduos da cultura de amendoim como fonte de nitrogênio para uma cultura de cobertura de centeio

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    Kipling Shane Balkcom

    2007-01-01

    Full Text Available Leguminous winter cover crops have been utilized in conservation systems to partially meet nitrogen (N requirements of succeeding summer cash crops, but the potential of summer legumes to reduce N requirements of a winter annual grass, used as a cover crop, has not been extensively examined. This study assessed the N contribution of peanut (Arachis hypogaea L. residues to a subsequent rye (Secale cereale L. cover crop grown in a conservation system on a Dothan sandy loam (fine-loamy, kaolinitic, thermic Plinthic Kandiudults at Headland, AL USA during the 2003-2005 growing seasons. Treatments were arranged in a split plot design, with main plots of peanut residue retained or removed from the soil surface, and subplots as N application rates (0, 34, 67 and 101 kg ha-1 applied in the fall. Peanut residue had minimal to no effect on rye biomass yields, N content, carbon (C /N ratio, or N, P, K, Ca and Zn uptake. Additional N increased rye biomass yield, and N, P, K, Ca, and Zn uptakes. Peanut residue does not contribute significant amounts of N to a rye cover crop grown as part of a conservation system, but retaining peanut residue on the soil surface could protect the soil from erosion early in the fall and winter before a rye cover crop grows sufficiently to protect the typically degraded southeastern USA soils.Culturas leguminosas de inverno tem sido utilizadas em sistemas conservacionistas para suprimento parcial das necessidades de nitrogênio (N de culturas subseqüentes de verão, mas o potencial destas culturas leguminosas de verão no sentido de reduzir as necessidades de N de gramíneas anuais de inverno, utilizadas como culturas de cobertura, ainda não foi extensivamente estudado. Este trabalho avaliou a contribuição dos resíduos de uma cultura de amendoim (Arachis hypogaea L. sobre as necessidades de N de uma cultura subsequente de centeio (Secale cereale L. como cobertura desenvolvida dentro de um sistema conservacionista, em um

  7. Comparison of radiocesium concentration changes in leguminous and non-leguminous herbaceous plants observed after the Fukushima Dai-ichi Nuclear Power Plant accident.

    Science.gov (United States)

    Uchida, Shigeo; Tagami, Keiko

    2018-06-01

    Transfer of radiocesium from soil to crops is an important pathway for human intake. In the period from one to two years after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, food monitoring results showed that radiocesium concentrations in soybean (a legume) were higher than those in other annual agricultural crops; in these crops, root uptake is the major pathway of radiocesium from soil to plant. However, it was not clear whether or not leguminous and non-leguminous herbaceous plants have different Cs uptake abilities from the same soil because crop sample collection fields were different. In this study, therefore, we compared the concentrations of 137 Cs in seven herbaceous plant species including two leguminous plants (Trifolium pratense L. and Vicia sativa L.) collected in 2012-2016 from the same sampling field in Chiba, Japan that had been affected by the FDNPP accident fallout. Among these species, Petasites japonicus (Siebold & Zucc.) Maxim. showed the highest 137 Cs concentration in 2012-2016. The correlation factor between all concentration data for 137 Cs and those for 40 K in these seven plants was R = 0.54 (p plants did not differ significantly, but 137 Cs data in the Poaceae family plants were significantly lower than those in T. pratense (p plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Intensity of Ground Cover Crop Arachis pintoi, Rhizobium Inoculation and Phosphorus Application and Their Effects on Field Growth and Nutrient Status of Cocoa Plants

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    John Bako Baon

    2006-08-01

    Full Text Available Arachis pintoiis potentially as a cover crop for cocoa (Theobroma cacaoL. farm, however information regarding its effect on the growth of cocoa plants in the field is very limited. The objective of this experiment is to investigate the combined influence of ground cover crop A. pintoi, rhizobial bacterial inoculation and phosphorus (P fertilizer on the growth of cocoa in the field and nutrient status. This experiment laid out in split-split plot design consisted of three levels of cover crop (without, A. pintoiand Calopogonium caeruleum, two levels of rhizobium inoculation (not inoculated and inoculated and two levels of phosphorus application (no P added and P added. The results showed that in field condition the presence of A. pintoias cover crop did not affect the growth of cocoa. On the other hand, C. caeruleumas cover crop tended to restrict cocoa growth compared to A. pintoi. Application of P increased leaf number of cocoa plant. Biomass production of A. pintoiwas 40% higher than C. caeruleum. Soil organic carbon and nitrogen contents were not affected by ground cover crops, though higher value (0.235% N and 1.63% organic C was obtained from combined treatments of inoculation and P addition or neither inoculation nor P addition. In the case of no rhizobium inoculation, soil N content in cocoa farm with A. pintoicover crop was lower than that of without cover crop or with C. caeruleum. Cover crop increased plant N content when there was no inoculation, on the other hand rhizobium inoculation decreased N content of cocoa tissue. Tissue P content of cocoa plant was not influenced by A. Pintoicover crop or by rhizobium inoculation, except that the P tissue content of cocoa was 28% higher when the cover crop was C. caeruleumand inoculated. Key words : Arachis pintoi, Theobroma cacao, Calopogonium caeruleum, rhizobium, nitrogen, phosphorus.

  9. Nutritional composition and in vitro digestibility of grass and legume winter (cover) crops.

    Science.gov (United States)

    Brown, A N; Ferreira, G; Teets, C L; Thomason, W E; Teutsch, C D

    2018-03-01

    In dairy farming systems, growing winter crops for forage is frequently limited to annual grasses grown in monoculture. The objectives of this study were to determine how cropping grasses alone or in mixtures with legumes affects the yield, nutritional composition, and in vitro digestibility of fresh and ensiled winter crops and the yield, nutritional composition, and in vitro digestibility of the subsequent summer crops. Experimental plots were planted with 15 different winter crops at 3 locations in Virginia. At each site, 4 plots of each treatment were planted in a randomized complete block design. The 15 treatments included 5 winter annual grasses [barley (BA), ryegrass (RG), rye (RY), triticale (TR), and wheat (WT)] in monoculture [i.e., no legumes (NO)] or with 1 of 2 winter annual legumes [crimson clover (CC) and hairy vetch (HV)]. After harvesting the winter crops, corn and forage sorghum were planted within the same plots perpendicular to the winter crop plantings. The nutritional composition and the in vitro digestibility of winter and summer crops were determined for fresh and ensiled samples. Growing grasses in mixtures with CC increased forage dry matter (DM) yield (2.84 Mg/ha), but the yield of mixtures with HV (2.47 Mg/ha) was similar to that of grasses grown in monoculture (2.40 Mg/ha). Growing grasses in mixtures with legumes increased the crude protein concentration of the fresh forage from 13.0% to 15.5% for CC and to 17.3% for HV. For neutral detergent fiber (NDF) concentrations, the interaction between grasses and legumes was significant for both fresh and ensiled forages. Growing BA, RY, and TR in mixtures with legumes decreased NDF concentrations, whereas growing RG and WT with legumes did not affect the NDF concentrations of either the fresh or the ensiled forages. Growing grasses in mixtures with legumes decreased the concentration of sugars of fresh forages relative to grasses grown in monoculture. Primarily, this decrease can be

  10. Anticipating potential biodiversity conflicts for future biofuel crops in South Africa: Incorporating land cover information with Species Distribution Models

    CSIR Research Space (South Africa)

    Blanchard, R

    2012-10-01

    Full Text Available % of biodiversity importance. Anticipating potential biodiversity confl icts for future biofuel crops in South Africa: Incorporating land cover information with Species Distribution Models R BLANCHARD1, DR P O?FARRELL1 AND PROF. D RICHARDSON2 1CSIR Natural... Resources and the Environment, PO Box 320, Stellenbosch, 7599, South Africa 2Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa Email: rblanchard@csir.co.za ? www...

  11. Soil microbial biomass under different management and tillage systems of permanent intercropped cover species in an orange orchard

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    Elcio Liborio Balota

    2011-12-01

    Full Text Available To mitigate soil erosion and enhance soil fertility in orange plantations, the permanent protection of the inter-rows by cover species has been suggested. The objective of this study was to evaluate alterations in the microbial biomass, due to different soil tillage systems and intercropped cover species between rows of orange trees. The soil of the experimental area previously used as pasture (Brachiaria humidicola was an Ultisol (Typic Paleudult originating from Caiuá sandstone in the northwestern part of the State of Paraná, Brazil. Two soil tillage systems were evaluated: conventional tillage (CT in the entire area and strip tillage (ST (strip width 2 m, in combination with different ground cover management systems. The citrus cultivar 'Pera' orange (Citrus sinensis grafted onto 'Rangpur' lime rootstock was used. Soil samples were collected after five years of treatment from a depth of 0-15 cm, under the tree canopy and in the inter-row, in the following treatments: (1 CT and an annual cover crop with the leguminous species Calopogonium mucunoides; (2 CT and a perennial cover crop with the leguminous peanut Arachis pintoi; (3 CT and an evergreen cover crop with Bahiagrass Paspalum notatum; (4 CT and a cover crop with spontaneous Brachiaria humidicola grass vegetation; and (5 ST and maintenance of the remaining grass (pasture of Brachiaria humidicola. Soil tillage and the different cover species influenced the microbial biomass, both under the tree canopy and in the inter-row. The cultivation of brachiaria increased C and N in the microbial biomass, while bahiagrass increased P in the microbial biomass. The soil microbial biomass was enriched in N and P by the presence of ground cover species and according to the soil P content. The grass species increased C, N and P in the soil microbial biomass from the inter-row more than leguminous species.

  12. Alternative cultivation systems for energy crops. Exploitation of phosphor and nitrogen in the cultivation of mixed fruits with leguminous plants under the conditions of drought stress; Alternative Anbausysteme fuer Energiepflanzen. Phosphor- und Stickstoffausnutzung im Mischfruchtanbau mit Leguminosen unter Trockenstressbedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Busch, Stefanie; Eichler-Loebermann, Bettina [Rostock Univ. (Germany). Professur Pflanzenbau

    2013-10-01

    Alternative cropping systems with an efficient utilization of resources are particularly interesting for energy cropping. The P- and N- uptake of phosphorus (P) and nitrogen (N) of maize and sorghum (here called ''energy crops'') intercropped with legumes (substitutive, 50:50) under drought conditions were investigated in a eight week pot experiment. Yield, P- and N- uptake of all species and mixtures were significantly lower under drought conditions than when well watered. The yield and the P-uptake of the mixtures was lower than of the sole cropped energy crops when well watered, but comparable under water deficit with exception of the sorghum mixtures, which reached a lower yield than sole sorghum. Despite the lower N-fertilization the N-uptake of the mixtures was comparable to the sole cropped maize or sorghum when well watered, but under drought N uptake of the mixtures was decreased in comparison to sole cropping. Under drought conditions the N-uptake of maize and sorghum plants in mixtures was not decreased, while the N-uptake of the legumes decreased in comparison to the well watered treatment. This may be an evidence for the benefit of the non-legumes in the investigated intercropping system under drought conditions. (orig.)

  13. Effects of a killed-cover crop mulching system on sweetpotato production, soil pests, and insect predators in South Carolina.

    Science.gov (United States)

    Jackson, D Michael; Harrison, Howard F

    2008-12-01

    Sweetpotatoes, Ipomoea batatas (L.) Lam. (Convolvulaceae), are typically grown on bare soil where weeds and erosion can be serious problems. Conservation tillage systems using cover crop residues as mulch can help reduce these problems, but little is known about how conservation tillage affects yield and quality of sweetpotato or how these systems impact populations of beneficial and pest insects. Therefore, field experiments were conducted at the U.S. Vegetable Laboratory, Charleston, SC, in 2002-2004 to evaluate production of sweetpotatoes in conventional tillage versus a conservation tillage system by using an oat (Avena sativa L. (Poaceae)-crimson clover (Trifolium incarnatum L.) (Fabaceae) killed-cover crop (KCC) mulch. The four main treatments were 1) conventional tillage, hand-weeded; 2) KCC, hand-weeded; 3) conventional tillage, weedy; and 4) KCC, weedy. Each main plot was divided into three subplots, whose treatments were sweetpotato genotypes: 'Ruddy', which is resistant to soil insect pests; and 'SC1149-19' and 'Beauregard', which are susceptible to soil insect pests. For both the KCC and conventional tillage systems, sweetpotato yields were higher in plots that received hand weeding than in weedy plots. Orthogonal contrasts revealed a significant effect of tillage treatment (conventional tillage versus KCC) on yield in two of the 3 yr. Ruddy remained resistant to injury by soil insect pests in both cropping systems; and it consistently had significantly higher percentages of clean roots and less damage by wireworm-Diabrotica-Systena complex, sweetpotato flea beetles, grubs, and sweetpotato weevils than the two susceptible genotypes. In general, injury to sweetpotato roots by soil insect pests was not significantly higher in the KCC plots than in the conventionally tilled plots. Also, more fire ants, rove beetles, and carabid beetle were captured by pitfall traps in the KCC plots than in the conventional tillage plots during at least 1 yr of the study

  14. Kenaf (Hibiscus cannabinus) and cowpea (Vigna unguiculata) as sugarcane cover crops

    Science.gov (United States)

    A Louisiana sugarcane field is typically replanted every four years due to declining yields, and, although, it is a costly process, it is both necessary and an opportunity to maximize the financial return during the next four year cropping cycle. Fallow planting systems (FPS) during the fallow perio...

  15. Evaluation of tillage, cover crop, and herbicide effects on weed control, yield, and grade in peanut

    Science.gov (United States)

    Peanut production plays a large role in agriculture in the Southeastern United States. Weeds are detrimental to their production because of the competition that they create; weeds will compete with crops for resources such as nutrients and sunlight, among others. Therefore, it is important to reduce...

  16. The Effect of Biofertilizers and Winter Cover Crops on Essential Oil Production and Some Agroecological Characteristics of Basil (Ocimum basilicum L.

    Directory of Open Access Journals (Sweden)

    M Jahan

    2013-04-01

    Full Text Available In searching for new strategies of medicinal plant production with high yield but without undesirable compounds or effects, it is important to investigate unconventional alternatives such as application of PGPR and cover crops cultivation. This experiment was conducted in a split plots arrangement with two factors based on randomized complete block design with three replications during years 2009-10, at Research Farm of Ferdowsi University of Mashhad. Cultivation and no cultivation of cover crops in autumn assigned to the main plots. The sub factor was biofertilizer application with four levels, included 1-Nitroxin (containing Azotobacter spp. and Azospirillum spp., 2-Biophosphorous (Bacillus sp. and Pseudomonas sp., 3-Nitroxin + Biophosphorous and 4-Control. During growing season plants were harvested by three cuts. Results showed that total shoots dry weight, leaves yield and LAI in plants under no cover crop cultivation had a significant advantage. Biofertilizers increased most characteristics e.g. fresh and dry total shoot yield, dry leaves and LAI. The interaction between fertilizer and cover crop was significant, as the highest yield of fresh shoots was observed in mix of nitroxin and biophosphorous with no cover crop, the highest and the lowest of leaf and green area index were obtained in plants treated by nitroxin without cover crop and biophosphorous with cover crop, respectively. Plants harvested in cut 3 had the lowest LAI and other two cuts had no significant difference concerning this trait. The highest and the lowest fresh and dry shoot yield were observed in cut 2 and 1, respectively. The most essential oil yield was in cut 2 and 3 (without significant difference and cut 1 was the lowest. The results showed that the interaction between biofertilizers and no cover crop cultivation was significant, as use of the biofertilizers especially nitroxin and biophosphorous in no cover crop condition enhanced the most characteristics of

  17. The short term influence of aboveground biomass cover crops on C sequestration and β–glucosidase in a vineyard ground under semiarid conditions

    Directory of Open Access Journals (Sweden)

    Fernando Peregrina

    2014-10-01

    Full Text Available Tillage and semiarid Mediterranean climatic conditions accelerate soil organic matter losses in Spanish vineyards. Previous studies showed that cover crops can increase soil organic carbon (SOC in Mediterranean vineyards. The objectives of this study were to evaluate the influence of two different cover crops in the short term on soil C sequestration in a semiarid vineyard and to study the potential use of both β–glucosidase enzimatic activity (GLU and the GLU/SOC ratio in order to assess the SOC increase. The experiment was carried out in a cv. Tempranillo (Vitis vinifera L. vineyard on a Oxyaquic Xerorthent soil in Rioja winegrowing region (NE, Spain. The experimental design was established in 2009 with three treatments: conventional tillage; sown barley cover crop (Hordeum vulgare, L.; sown Persian clover cover crop (Trifolium resupinatum L.. Carbon in the aboveground biomass with each cover crop was monitored. Soil was sampled in June 2011 and June 2012, and SOC, GLU and the GLU/SOC ratio were determined. After 3 years both cover crops increased SOC at soil surface with C sequestration rates of 0.47 and 1.19 t C ha-1 yr-1 for BV and CV respectively. GLU and GLU/SOC ratio increased in both cover crops at 0-5 cm soil depth. The C sequestration rates and GLU were related to the cover crops aboveground biomass. In consequence, in semiarid vineyards under cover crops GLU could be an appropriate indicator to asses the increase of SOC and the soil quality improvement in the short-term (2-3 years.

  18. Effect of cover crops on emergence and growth of carrot (Daucus carota L. in no-plow and traditional tillage

    Directory of Open Access Journals (Sweden)

    Marzena Błażewicz-Woźniak

    2015-03-01

    Full Text Available The aim of the experiment was to determine the influence of cover crop biomass incorporated into the soil at different times and using different treatments on carrot emergence and growth. 7 species of cover crops were included in the study: Secale cereale, Avena sativa, Vicia sativa, Sinapis alba, Phacelia tanacetifolia, Fagopyrum esculentum, and Helianthus annuus.  Number of emerged carrot plants significantly depended on the cover crop used and on the method of pre-winter and spring pre-sowing tillage. Carrot emerged best after a rye or oats cover crop. Regardless of the cover crop species used, the largest number of carrots emerged in cultivation on ridges. In other variants of no-plow tillage, number of seedlings was significantly lower and did not differ from that under traditional plow tillage. The highest leaf rosettes were formed by carrot growing after a rye or oats cover crop. The highest rosettes were produced by carrots in the treatments where tillage was limited to the use of a tillage implement in spring and the lowest ones after pre-winter plowing. The effect of tillage on the emergence and height of carrot leaves largely depended on weather conditions in the successive years of the study. The largest number of leaves was found in carrots grown after a buckwheat cover crop and in cultivation without cover crop, while the smallest one after phacelia and white mustard. Carrots produced the largest number of leaves after a sunflower cover crop and the use of a tillage implement in spring, while the number of leaves was lowest when the mustard biomass was incorporated into the soil in spring. The use of cover crops significantly increased the mass of leaves produced by carrot as compared to the cultivation without cover crop. The largest mass of leaves was produced by carrots grown after the phacelia and mustard cover crops. Conventional plow tillage and pre-winter tillage using a stubble cultivator promoted an increase in the mass

  19. Weed infestation of spring common wheat (Triticum aestivum L. grown in monoculture depending on the cover crop and weed control method

    Directory of Open Access Journals (Sweden)

    Dorota Gawęda

    2012-10-01

    Full Text Available The aim of this 3-year field study was to evaluate the effect of some stubble crops and in-crop weed control methods on the species composition, number and air-dry weight of weeds in a wheat crop grown in short-term monoculture. The study was conducted in the period 2009-2011 in the Uhrusk Experimental Farm on mixed rendzina soil classified as very good rye soil complex. It included various types of stubble crops ploughed in each year (control treatment without cover crop, white mustard, lacy phacelia, a mixture of legumes – narrow-leaf lupin + field pea and methods of weed control in spring wheat (mechanical, mechanical and chemical, chemical weed control. On average during the study period, all stubble crops used reduced the air-dry weight of weds in the treatments with mechanical weed management relative to the control treatment. Irrespective of the weed control method, the number of weeds in the wheat crop was significantly lower only after the ploughing in of white mustard. Mechanical weed management proved to be less effective in reducing the number and dry weight of weeds compared to other weed control methods. The white mustard and legume mixture cover crops had a reducing effect on the number of weed species in relation to the treatment without cover crops. The highest floristic diversity of weed communities was found in the spring wheat crop in which only mechanical weeding alone was used.

  20. The ability of cover crops to reduce nitrogen and phosphorus losses from arable land in southern Scandinavia and Finland

    DEFF Research Database (Denmark)

    Aronsson, H.; Hansen, Elly Møller; Thomsen, Ingrid Kaag

    2016-01-01

    This review summarizes current knowledge from the literature and experimental studies on the role of cover crops (CCs) in reducing nitrogen (N) leaching and phosphorus (P) losses to waters under the marine and humid continental climate conditions of southern Scandinavia and Finland. Field leaching...... CC biomass. CCs have been implemented to varying degrees into agri-environmental programs. They are mandatory in Denmark and subsidized in Norway, Sweden, and Finland. CCs are grown on 8% of arable land in Denmark, 5% in Sweden, 1% in Finland, and 0.5% in Norway, but CC area is now increasing...... systems with harvesting of biomass). There is also a need to devise balanced solutions for maintaining and increasing the frequency of CCs in crop rotations to exploit the possible benefits of CCs in reducing nutrient losses....

  1. Classification of rare land cover types: Distinguishing annual and perennial crops in an agricultural catchment in South Korea.

    Science.gov (United States)

    Bogner, Christina; Seo, Bumsuk; Rohner, Dorian; Reineking, Björn

    2018-01-01

    Many environmental data are inherently imbalanced, with some majority land use and land cover types dominating over rare ones. In cultivated ecosystems minority classes are often the target as they might indicate a beginning land use change. Most standard classifiers perform best on a balanced distribution of classes, and fail to detect minority classes. We used the synthetic minority oversampling technique (smote) with Random Forest to classify land cover classes in a small agricultural catchment in South Korea using modis time series. This area faces a major soil erosion problem and policy measures encourage farmers to replace annual by perennial crops to mitigate this issue. Our major goal was therefore to improve the classification performance on annual and perennial crops. We compared four different classification scenarios on original imbalanced and synthetically oversampled balanced data to quantify the effect of smote on classification performance. smote substantially increased the true positive rate of all oversampled minority classes. However, the performance on minor classes remained lower than on the majority class. We attribute this result to a class overlap already present in the original data set that is not resolved by smote. Our results show that resampling algorithms could help to derive more accurate land use and land cover maps from freely available data. These maps can be used to provide information on the distribution of land use classes in heterogeneous agricultural areas and could potentially benefit decision making.

  2. Cover Image Identification of Plant Species for Crop Pollinator Habitat Enhancement in the Northern Prairies

    Directory of Open Access Journals (Sweden)

    Diana Bizecki Robson

    2014-09-01

    Full Text Available Wild pollinators have a positive impact on the productivity of insect-pollinated crops. Consequently, landowners are being encouraged to maintain and grow wildflower patches to provide habitat for important pollinators. Research on plant-pollinator interaction matrices indicates that a small number of “core” plants provide a disproportionately high amount of pollen and nectar to insects. This matrix data can be used to help design wildflower plantings that provide optimal resources for desirable pollinators. Existing interaction matrices from three tall grass prairie preserves in the northern prairies were used to identify core plant species that are visited by wild pollinators of a common insect-pollinated crop, namely canola (Brassica napus L.. The wildflower preferences of each insect taxon were determined using quantitative insect visitation and floral abundance data. Phenology data were used to calculate the degree of floral synchrony between the wildflowers and canola. Using this information I ranked the 41 wildflowers that share insect visitors with canola according to how useful they are for providing pollinators with forage before and after canola flowers. The top five species were smooth blue aster (Symphyotrichum laeve (L. A. & D. Löve, stiff goldenrod (Solidago rigida L., wild bergamot (Monarda fistulosa L., purple prairie-clover (Dalea purpurea Vent. and Lindley’s aster (Symphyotrichum ciliolatum (Lindl. A. & D. Löve. By identifying the most important wild insects for crop pollination, and determining when there will be “pollen and nectar gaps”, appropriate plant species can be selected for companion plantings to increase pollinator populations and crop production.

  3. Impacts of Watershed Characteristics and Crop Rotations on Winter Cover Crop Nitrate-Nitrogen Uptake Capacity within Agricultural Watersheds in the Chesapeake Bay Region.

    Directory of Open Access Journals (Sweden)

    Sangchul Lee

    Full Text Available The adoption rate of winter cover crops (WCCs as an effective conservation management practice to help reduce agricultural nutrient loads in the Chesapeake Bay (CB is increasing. However, the WCC potential for water quality improvement has not been fully realized at the watershed scale. This study was conducted to evaluate the long-term impact of WCCs on hydrology and NO3-N loads in two adjacent watersheds and to identify key management factors that affect the effectiveness of WCCs using the Soil and Water Assessment Tool (SWAT and statistical methods. Simulation results indicated that WCCs are effective for reducing NO3-N loads and their performance varied based on planting date, species, soil characteristics, and crop rotations. Early-planted WCCs outperformed late-planted WCCs on the reduction of NO3-N loads and early-planted rye (RE reduced NO3-N loads by ~49.3% compared to the baseline (no WCC. The WCCs were more effective in a watershed dominated by well-drained soils with increased reductions in NO3-N fluxes of ~2.5 kg N·ha-1 delivered to streams and ~10.1 kg N·ha-1 leached into groundwater compared to poorly-drained soils. Well-drained agricultural lands had higher transport of NO3-N in the soil profile and groundwater due to increased N leaching. Poorly-drained agricultural lands had lower NO3-N due to extensive drainage ditches and anaerobic soil conditions promoting denitrification. The performance of WCCs varied by crop rotations (i.e., continuous corn and corn-soybean, with increased N uptake following soybean crops due to the increased soil mineral N availability by mineralization of soybean residue compared to corn residue. The WCCs can reduce N leaching where baseline NO3-N loads are high in well-drained soils and/or when residual and mineralized N availability is high due to the cropping practices. The findings suggested that WCC implementation plans should be established in watersheds according to local edaphic and agronomic

  4. Impacts of Watershed Characteristics and Crop Rotations on Winter Cover Crop Nitrate-Nitrogen Uptake Capacity within Agricultural Watersheds in the Chesapeake Bay Region.

    Science.gov (United States)

    Lee, Sangchul; Yeo, In-Young; Sadeghi, Ali M; McCarty, Gregory W; Hively, W Dean; Lang, Megan W

    2016-01-01

    The adoption rate of winter cover crops (WCCs) as an effective conservation management practice to help reduce agricultural nutrient loads in the Chesapeake Bay (CB) is increasing. However, the WCC potential for water quality improvement has not been fully realized at the watershed scale. This study was conducted to evaluate the long-term impact of WCCs on hydrology and NO3-N loads in two adjacent watersheds and to identify key management factors that affect the effectiveness of WCCs using the Soil and Water Assessment Tool (SWAT) and statistical methods. Simulation results indicated that WCCs are effective for reducing NO3-N loads and their performance varied based on planting date, species, soil characteristics, and crop rotations. Early-planted WCCs outperformed late-planted WCCs on the reduction of NO3-N loads and early-planted rye (RE) reduced NO3-N loads by ~49.3% compared to the baseline (no WCC). The WCCs were more effective in a watershed dominated by well-drained soils with increased reductions in NO3-N fluxes of ~2.5 kg N·ha-1 delivered to streams and ~10.1 kg N·ha-1 leached into groundwater compared to poorly-drained soils. Well-drained agricultural lands had higher transport of NO3-N in the soil profile and groundwater due to increased N leaching. Poorly-drained agricultural lands had lower NO3-N due to extensive drainage ditches and anaerobic soil conditions promoting denitrification. The performance of WCCs varied by crop rotations (i.e., continuous corn and corn-soybean), with increased N uptake following soybean crops due to the increased soil mineral N availability by mineralization of soybean residue compared to corn residue. The WCCs can reduce N leaching where baseline NO3-N loads are high in well-drained soils and/or when residual and mineralized N availability is high due to the cropping practices. The findings suggested that WCC implementation plans should be established in watersheds according to local edaphic and agronomic

  5. On the Ground or in the Air? A Methodological Experiment on Crop Residue Cover Measurement in Ethiopia

    Science.gov (United States)

    Kosmowski, Frédéric; Stevenson, James; Campbell, Jeff; Ambel, Alemayehu; Haile Tsegay, Asmelash

    2017-10-01

    Maintaining permanent coverage of the soil using crop residues is an important and commonly recommended practice in conservation agriculture. Measuring this practice is an essential step in improving knowledge about the adoption and impact of conservation agriculture. Different data collection methods can be implemented to capture the field level crop residue coverage for a given plot, each with its own implication on survey budget, implementation speed and respondent and interviewer burden. In this paper, six alternative methods of crop residue coverage measurement are tested among the same sample of rural households in Ethiopia. The relative accuracy of these methods are compared against a benchmark, the line-transect method. The alternative methods compared against the benchmark include: (i) interviewee (respondent) estimation; (ii) enumerator estimation visiting the field; (iii) interviewee with visual-aid without visiting the field; (iv) enumerator with visual-aid visiting the field; (v) field picture collected with a drone and analyzed with image-processing methods and (vi) satellite picture of the field analyzed with remote sensing methods. Results of the methodological experiment show that survey-based methods tend to underestimate field residue cover. When quantitative data on cover are needed, the best estimates are provided by visual-aid protocols. For categorical analysis (i.e., >30% cover or not), visual-aid protocols and remote sensing methods perform equally well. Among survey-based methods, the strongest correlates of measurement errors are total farm size, field size, distance, and slope. Results deliver a ranking of measurement options that can inform survey practitioners and researchers.

  6. Radiation budget in green beans crop with and without polyethylene cover

    International Nuclear Information System (INIS)

    Souza, J.L. de; Escobedo, J.F.

    1997-01-01

    The radiation budget in agricultural crops is very important on the microclimate characterization, on the water losses determination and on dry matter accumulation of vegetation. This work describes the radiation budget determination in a green beans crop (Phaseolus vulgaris L.), in Botucatu, SP, Brazil (22° 54′S; 48° 27′W; 850 m), under two different conditions: the normal field culture and in a polyethylene greenhouse. The densities of fluxes of radiation were used to construct diurnal curves of the components of global radiation (Rg), reflected radiation (Rr), net radiation (Rn).The arithmetic's relations allowed to obtain the components net short-waves (Rc) and net long-waves (Rl). The analysis of these components related to the leaf area index (LAI) in many phenological phases of the culture showed Rg distributed in 68%, 85%, 17% and 66%, 76%, 10% to Rn, Rc and Rl in the internal and external ambients in a polyethylene greenhouse, respectively [pt

  7. Use of nitrogen from fertilizer and cover crops by upland rice in an Oxisol under no-tillage in the Cerrado

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Edson Cabral da; Muraoka, Takashi; Bendassolli, Jose Alberto, E-mail: edsoncabralsilva@gmail.com, E-mail: muraoka@cena.usp.br, E-mail: jab@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil); Franzini, Vinicius Ide, E-mail: vinicius.franzini@embrapa.br [Embrapa Amazonia Oriental, Belem, PA (Brazil); Sakadevan, Karuppan, E-mail: K.Sakadevan@iaea.org [Joint FAO/IAEA, Division of Nuclear Techniques in Food and Agriculture, Soil and Water Management and Crop Nutrition Subprogram, Vienna International Centre, Vienna (Austria); Buzetti, Salatier; Arf, Orivaldo, E-mail: sbuzetti@agr.feis.unesp.br, E-mail: arf@agr.feis.unesp.br [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Ilha Solteira, SP (Brazil). Faculdade de Engenharia; Soares, Frederico Antonio Loureiro, E-mail: fredalsoares@hotmail.com [Instituto Federal Goiano, Rio Verde, GO (Brazil)

    2016-06-15

    The objective of this work was to evaluate the effects of cover crops on the yield of upland rice (Oryza sativa) grown under no-tillage system, in the presence and absence of N fertilizer, as well as to quantify, in the field, the use efficiency of N from urea and cover crops by upland rice, through the {sup 15}N isotope dilution technique. The field experiment was carried out in the municipality of Selviria, in the state of Mato Grosso do Sul, Brazil, in an Oxisol (Rhodic Hapludox) in the Cerrado (Brazilian savanna) region. The experimental design was a randomized complete block with 15 treatments and four replicates, in a 5 x 3 factorial arrangement. The treatments were four cover crops (Crotalaria juncea, Cajanus cajan, Mucuna pruriens, and Pennisetum glaucum) + spontaneous vegetation (fallow in off-season), combined with three forms of N fertilization: control treatment, without N fertilizer application; 20 kg ha{sup -1} N at sowing; and 20 kg ha{sup -1} N at sowing plus 60 kg ha{sup -1} N as topdressing. Rice is not affected by N fertilizer application as topdressing, when legume cover crops are used. The use of legume cover crops provides higher grain yield and use of fertilizer-N by rice than that of millet or fallow. Legume cover crops promote an effect equivalent to that of the application of 60 kg ha{sup -1} N as urea on rice yield. (author)

  8. Improved crop residue cover estimates by coupling spectral indices for residue and moisture

    Science.gov (United States)

    Remote sensing assessment of soil residue cover (fR) and tillage intensity will improve our predictions of the impact of agricultural practices and promote sustainable management. Spectral indices for estimating fR are sensitive to soil and residue water content, therefore, the uncertainty of estima...

  9. Influence on wine biogenic amine composition of modifications to soil N availability and grapevine N by cover crops.

    Science.gov (United States)

    Pérez-Álvarez, Eva P; Garde-Cerdán, Teresa; Cabrita, Maria João; García-Escudero, Enrique; Peregrina, Fernando

    2017-11-01

    Vineyard soil management can modify the nitrogen soil availability and, therefore, grape amino acid content. These compounds are precursors of biogenic amines, which have negative effects on wine quality and human health. The objective was to study whether the effect of conventional tillage and two cover crops (barley and clover) on grapevine nitrogen status could be related to wine biogenic amines. Over 4 years, soil NO 3 - -N, nitrogen content in leaf and wine biogenic amine concentration were determined. Barley reduced soil NO 3 - -N availability and clover increased it. In 2011, at bloom, nitrogen content decreased with barley treatment in both blade and petiole. In 2012, nitrogen content in both leaf tissues at bloom was greater with clover than with tillage and barley treatments. Also, total biogenic amines decreased in barley with respect to tillage and clover treatments. There were correlations between some individual and total biogenic amine concentrations with respect to nitrogen content in leaf tissues. Wine biogenic amine concentration can be affected by the grapevine nitrogen status, provoked by changes in the soil NO 3 - -N availability with both cover crop treatments. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  10. Do cover crops enhance N₂O, CO₂ or CH₄ emissions from soil in Mediterranean arable systems?

    Science.gov (United States)

    Sanz-Cobena, A; García-Marco, S; Quemada, M; Gabriel, J L; Almendros, P; Vallejo, A

    2014-01-01

    This study evaluates the effect of planting three cover crops (CCs) (barley, Hordeum vulgare L.; vetch, Vicia villosa L.; rape, Brassica napus L.) on the direct emission of N₂O, CO₂ and CH₄ in the intercrop period and the impact of incorporating these CCs on the emission of greenhouse gas (GHG) from the forthcoming irrigated maize (Zea mays L.) crop. Vetch and barley were the CCs with the highest N₂O and CO₂ losses (75 and 47% increase compared with the control, respectively) in the fallow period. In all cases, fluxes of N₂O were increased through N fertilization and the incorporation of barley and rape residues (40 and 17% increase, respectively). The combination of a high C:N ratio with the addition of an external source of mineral N increased the fluxes of N₂O compared with -Ba and -Rp. The direct emissions of N₂O were lower than expected for a fertilized crop (0.10% emission factor, EF) compared with other studies and the IPCC EF. These results are believed to be associated with a decreased NO₃(-) pool due to highly denitrifying conditions and increased drainage. The fluxes of CO₂ were in the range of other fertilized crops (i.e., 1118.71-1736.52 kg CO₂-Cha(-1)). The incorporation of CC residues enhanced soil respiration in the range of 21-28% for barley and rape although no significant differences between treatments were detected. Negative CH₄ fluxes were measured and displayed an overall sink effect for all incorporated CC (mean values of -0.12 and -0.10 kg CH₄-Cha(-1) for plots with and without incorporated CCs, respectively). © 2013 Elsevier B.V. All rights reserved.

  11. Antifungal proteins and peptides of leguminous and non-leguminous origins.

    Science.gov (United States)

    Ng, T B

    2004-07-01

    Antifungal proteins and peptides, as their names imply, serve a protective function against fungal invasion. They are produced by a multitude of organisms including leguminous flowering plants, non-leguminous flowering plants, gymnosperms, fungi, bacteria, insects and mammals. The intent of the present review is to focus on the structural and functional characteristics of leguminous, as well as non-leguminous, antifungal proteins and peptides. A spectacular diversity of amino acid sequences has been reported. Some of the antifungal proteins and peptides are classified, based on their structures and/or functions, into groups including chitinases, glucanases, thaumatin-like proteins, thionins, and cyclophilin-like proteins. Some of the well-known proteins such as lectins, ribosome inactivating proteins, ribonucleases, deoxyribonucleases, peroxidases, and protease inhibitors exhibit antifungal activity. Different antifungal proteins may demonstrate different fungal specificities. The mechanisms of antifungal action of only some antifungal proteins including thaumatin-like proteins and chitinases have been elucidated.

  12. Determination of Germination Response to Temperature and Water Potential for a Wide Range of Cover Crop Species and Related Functional Groups.

    Science.gov (United States)

    Tribouillois, Hélène; Dürr, Carolyne; Demilly, Didier; Wagner, Marie-Hélène; Justes, Eric

    2016-01-01

    A wide range of species can be sown as cover crops during fallow periods to provide various ecosystem services. Plant establishment is a key stage, especially when sowing occurs in summer with high soil temperatures and low water availability. The aim of this study was to determine the response of germination to temperature and water potential for diverse cover crop species. Based on these characteristics, we developed contrasting functional groups that group species with the same germination ability, which may be useful to adapt species choice to climatic sowing conditions. Germination of 36 different species from six botanical families was measured in the laboratory at eight temperatures ranging from 4.5-43°C and at four water potentials. Final germination percentages, germination rate, cardinal temperatures, base temperature and base water potential were calculated for each species. Optimal temperatures varied from 21.3-37.2°C, maximum temperatures at which the species could germinate varied from 27.7-43.0°C and base water potentials varied from -0.1 to -2.6 MPa. Most cover crops were adapted to summer sowing with a relatively high mean optimal temperature for germination, but some Fabaceae species were more sensitive to high temperatures. Species mainly from Poaceae and Brassicaceae were the most resistant to water deficit and germinated under a low base water potential. Species were classified, independent of family, according to their ability to germinate under a range of temperatures and according to their base water potential in order to group species by functional germination groups. These groups may help in choosing the most adapted cover crop species to sow based on climatic conditions in order to favor plant establishment and the services provided by cover crops during fallow periods. Our data can also be useful as germination parameters in crop models to simulate the emergence of cover crops under different pedoclimatic conditions and crop

  13. Dynamics of nonpersistent aphid-borne viruses in lettuce crops covered with UV-absorbing nets.

    Science.gov (United States)

    Legarrea, S; Betancourt, M; Plaza, M; Fraile, A; García-Arenal, F; Fereres, A

    2012-04-01

    Aphid-transmitted viruses frequently cause severe epidemics in lettuce grown under Mediterranean climates. Spatio-temporal dynamics of aphid-transmitted viruses and its vector were studied on lettuce (Lactuca sativa L.) grown under tunnels covered by two types of nets: a commercial UV-absorbing net (Bionet) and a Standard net. A group of plants infected by Cucumber mosaic virus (CMV, family Bromoviridae, genus Cucumovirus) and Lettuce mosaic virus (LMV, family Potyviridae, genus Potyvirus) was transplanted in each plot. The same virus-infected source plants were artificially infested by the aphid Macrosiphum euphorbiae (Thomas). Secondary spread of insects was weekly monitored and plants were sampled for the detection of viruses every two weeks. In 2008, the infection rate of both CMV and LMV were lower under the Bionet than under the Standard cover, probably due to the lower population density and lower dispersal rate achieved by M. euphorbiae. However, during spring of 2009, significant differences in the rate of infection between the two covers were only found for LMV six weeks after transplant. The spatial distribution of the viruses analysed by SADIE methodology was "at random", and it was not associated to the spatial pattern of the vector. The results obtained are discussed analyzing the wide range of interactions that occurred among UV-radiation, host plant, viruses, insect vector and environmental conditions. Our results show that UV-absorbing nets can be recommended as a component of an integrated disease management program to reduce secondary spread of lettuce viruses, although not as a control measure on its own. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. What is the potential of cropland albedo management in the fight against global warming? A case study based on the use of cover crops

    Science.gov (United States)

    Carrer, Dominique; Pique, Gaétan; Ferlicoq, Morgan; Ceamanos, Xavier; Ceschia, Eric

    2018-04-01

    Land cover management in agricultural areas is a powerful tool that could play a role in the mitigation of climate change and the counterbalance of global warming. First, we attempted to quantify the radiative forcing that would increase the surface albedo of croplands in Europe following the inclusion of cover crops during the fallow period. This is possible since the albedo of bare soil in many areas of Europe is lower than the albedo of vegetation. By using satellite data, we demonstrated that the introduction of cover crops into the crop rotation during the fallow period would increase the albedo over 4.17% of Europe’s surface. According to our study, the effect resulting from this increase in the albedo of the croplands would be equivalent to a mitigation of 3.16 MtCO2-eq.year‑1 over a 100 year time horizon. This is equivalent to a mitigation potential per surface unit (m2) of introduced cover crop over Europe of 15.91 gCO2-eq.year‑1.m‑2. This value, obtained at the European scale, is consistent with previous estimates. We show that this mitigation potential could be increased by 27% if the cover crop is maintained for a longer period than 3 months and reduced by 28% in the case of no irrigation. In the second part of this work, based on recent studies estimating the impact of cover crops on soil carbon sequestration and the use of fertilizer, we added the albedo effect to those estimates, and we argued that, by considering areas favourable to their introduction, cover crops in Europe could mitigate human-induced agricultural greenhouse gas emissions by up to 7% per year, using 2011 as a reference. The impact of the albedo change per year would be between 10% and 13% of this total impact. The countries showing the greatest mitigation potentials are France, Bulgaria, Romania, and Germany.

  15. A comparative analysis to quantify the biogeochemical and biogeophysical cooling effects on climate of a white mustard cover crop

    Science.gov (United States)

    Ferlicoq, Morgan; Ceschia, Eric; Brut, Aurore; Tallec, Tiphaine; Carrer, Dominique; Pique, Gaetan; Ferroni, Nicole

    2017-04-01

    During the COP21, agriculture was recognised as a strategic sector and an opportunity to strengthen climate mitigation. In particular, the "4 per 1000" initiative relies upon solutions that refer to agro-ecology, conservation agriculture, … that could lead to increase carbon storage. Among those agro-ecology practices, including cover crops during fallow periods is considered as a fundamental agronomic lever for storing carbon. However, if biogeochemical benefits of cover-crops (CC) have already been addressed, their biogeophysical effects on climate have never been quantified and compared to biogeochemical effects. This comparative study (CC vs. bare soil), quantified and compared biogeochemical (including carbon storage) and biophysical effects (albedo and energy partitioning effect) of CC on climate. An experimental campaign was performed in 2013 in Southwest France, during the fallow period following a winter-wheat crop (and before a maize). The experimental plot was divided in two: the northern part was maintained in bare soil (BS) while white-mustard (WM) was grown during 3-months on the southern part. On each subplot, continuous measurements of CO2, latent and sensible fluxes (by eddy covariance) and solar radiation were acquired. Also, N2O emissions were measured by means of automatic chambers on each subplots. Moreover, by using a Life-Cycle-Analysis approach, each component of the greenhouse gas budget (GHGB) was quantified for each subplot, including emissions associated to field operations (FO). To quantify the albedo induced radiative forcing (RFα) caused by the white-mustard, the bare soil subplot was used as a reference state (IPCC, 2007). Finally, the net radiative forcing for each subplot was calculated as the sum of biogeochemical and biogeophysical (albedo effect) radiative forcing. The white-mustard allowed a net CO2 fixation of 63 g C-eq.m-2, corresponding to 20% of the net annual CO2 flux that year (-332 g C-eq.m-2). Through the WM seeds

  16. Effects of Planting Dates, Irrigation Management and Cover Crops on Growth and Yield of Saffron (Crocus sativus L.

    Directory of Open Access Journals (Sweden)

    A Koocheki

    2017-01-01

    coming spring (May, 2010. Therefore, data were analyzed as split-plot in the first year and split-split-plot in the second year. Data analysis was done using SAS 9.1 and means were compared using Duncan multiple range test in 5% level of probability. Results and discussion Results showed that most growth and flowering indices of saffron were significantly affected by experimental factors. Quantitative indices of saffron were decreased considerably by delaying in planting date in both studied years. The highest flower yield was obtained in June planting date (28 and 98 kg.ha-1 in 2009 and 2010, respectively, while the lowest was shown in October planting date (18 and 34 kg.ha-1 in 2009 and 2010, respectively. Enhanced growth and yield of saffron in spring planting date is because of real dormancy stage of corms in this time. All studied indices were superior in no-irrigated treatments after planting in both studied years. The flower yield was 9 and 43 kg.ha-1 in 2009 and 2010 in irrigated treatments, respectively, while these values were 37 and 78 kg.ha-1in 2009 and 2010 in no-irrigation treatment, respectively. It has been reported that irrigation during the creation of the primary leaves in the corm buds is negative, while irrigation after this period and simultaneous with the beginning of primary reproductive organs creation is suitable for saffron flowering. The application of cover crops improved partially the quantitative indices of saffron, particularly in Bitter vetch treatment. In addition, the highest flowering rate and the lowest leaf appearance rate were observed in June planting date, no-irrigation and Bitter vetch cover crop treatment. The positive effects of short-growth cycle companion crops on saffron is related to improvement of soil physical, biological and chemical properties, soil temperature regulation, prevention from nutrient leaching, N-fixation by Fabaceae species and help to weeds control. Conclusion In total, saffron corm planting few days

  17. PEMANFAATAN LEGUM COVER CROP UNTUK MEMPERBAIKI SIFAT KIMIA TANAH PADA LAHAN BEKAS TAMBANG EMAS DI KABUPATEN SIJUNJUNG

    Directory of Open Access Journals (Sweden)

    Giska Oktabriana

    2018-01-01

    ABSTRACT Sijunjung is one of the regencies in West Sumatra, which has reserves of gold mines. Gold mining in Sijunjung usually done illegally conducted dialiran river and spread the paddy rice is traditionally owned by the community. Problems encountered on mined land is that low productivity due to less good is the chemical properties of the soil it self like acid soil, N-total, P-available, cation exchange capacity (CEC and the content of bases (K, Ca, Mg and Na is low and Al dissolved in the soil is very high. One way you can do to fix it is by the use of Legume Cover Crop (LCC which is able to live on land that is damaged and is useful to protect the soil from erosion damage and is able to produce large amounts of organic matter. The purpose of this research is to improve the chemical properties of the gold mined land and to determine the type of Legume Cover Crop (LCC are good at improving the chemical nature of the gold mined lands. This research was conducted in Nagari Koto subdistrict Pala Outer Seven Sijunjung for 3 months and continued with the analysis in the Laboratory of Soil Faculty of Agriculture, Andalas University. The design used in this study is a randomized block design (RAK with 5 treatments and 3 replications, treatment plant use LCC where, A = Control (without LCC,B =Mucuna conchinchinensis, C = Calopogonium mucunoide, D =Centrocema pubescen, E = Mucuna bracteata. Data analysis using Anova table 5% if F count is count more than F table 5% and a further test HSD 5%. From the research results can be concluded that the use of LCC M. conchinchinensisable to improve soil chemical properties in the gold mining land in Sijunjung.

  18. Effect of cover crops on greenhouse gas emissions in an irrigated field under integrated soil fertility management

    Science.gov (United States)

    Guardia, Guillermo; Abalos, Diego; García-Marco, Sonia; Quemada, Miguel; Alonso-Ayuso, María; Cárdenas, Laura M.; Dixon, Elizabeth R.; Vallejo, Antonio

    2016-09-01

    Agronomical and environmental benefits are associated with replacing winter fallow by cover crops (CCs). Yet, the effect of this practice on nitrous oxide (N2O) emissions remains poorly understood. In this context, a field experiment was carried out under Mediterranean conditions to evaluate the effect of replacing the traditional winter fallow (F) by vetch (Vicia sativa L.; V) or barley (Hordeum vulgare L.; B) on greenhouse gas (GHG) emissions during the intercrop and the maize (Zea mays L.) cropping period. The maize was fertilized following integrated soil fertility management (ISFM) criteria. Maize nitrogen (N) uptake, soil mineral N concentrations, soil temperature and moisture, dissolved organic carbon (DOC) and GHG fluxes were measured during the experiment. Our management (adjusted N synthetic rates due to ISFM) and pedo-climatic conditions resulted in low cumulative N2O emissions (0.57 to 0.75 kg N2O-N ha-1 yr-1), yield-scaled N2O emissions (3-6 g N2O-N kg aboveground N uptake-1) and N surplus (31 to 56 kg N ha-1) for all treatments. Although CCs increased N2O emissions during the intercrop period compared to F (1.6 and 2.6 times in B and V, respectively), the ISFM resulted in similar cumulative emissions for the CCs and F at the end of the maize cropping period. The higher C : N ratio of the B residue led to a greater proportion of N2O losses from the synthetic fertilizer in these plots when compared to V. No significant differences were observed in CH4 and CO2 fluxes at the end of the experiment. This study shows that the use of both legume and nonlegume CCs combined with ISFM could provide, in addition to the advantages reported in previous studies, an opportunity to maximize agronomic efficiency (lowering synthetic N requirements for the subsequent cash crop) without increasing cumulative or yield-scaled N2O losses.

  19. Evaluating the relationship between biomass, percent groundcover and remote sensing indices across six winter cover crop fields in Maryland, United States

    Science.gov (United States)

    Prabhakara, Kusuma; Hively, W. Dean; McCarty, Gregory W.

    2015-07-01

    Winter cover crops are an essential part of managing nutrient and sediment losses from agricultural lands. Cover crops lessen sedimentation by reducing erosion, and the accumulation of nitrogen in aboveground biomass results in reduced nutrient runoff. Winter cover crops are planted in the fall and are usually terminated in early spring, making them susceptible to senescence, frost burn, and leaf yellowing due to wintertime conditions. This study sought to determine to what extent remote sensing indices are capable of accurately estimating the percent groundcover and biomass of winter cover crops, and to analyze under what critical ranges these relationships are strong and under which conditions they break down. Cover crop growth on six fields planted to barley, rye, ryegrass, triticale or wheat was measured over the 2012-2013 winter growing season. Data collection included spectral reflectance measurements, aboveground biomass, and percent groundcover. Ten vegetation indices were evaluated using surface reflectance data from a 16-band CROPSCAN sensor. Restricting analysis to sampling dates before the onset of prolonged freezing temperatures and leaf yellowing resulted in increased estimation accuracy. There was a strong relationship between the normalized difference vegetation index (NDVI) and percent groundcover (r2 = 0.93) suggesting that date restrictions effectively eliminate yellowing vegetation from analysis. The triangular vegetation index (TVI) was most accurate in estimating high ranges of biomass (r2 = 0.86), while NDVI did not experience a clustering of values in the low and medium biomass ranges but saturated in the higher range (>1500 kg/ha). The results of this study show that accounting for index saturation, senescence, and frost burn on leaves can greatly increase the accuracy of estimates of percent groundcover and biomass for winter cover crops.

  20. Investigation the Vertical Distribution of Leaf Area and Dry Matter of Sweet Basil (Ocimum basilicum L., Borage (Borago officinalis L. and Cover Crops in Competition with Weeds

    Directory of Open Access Journals (Sweden)

    zeinab shirzadi margavi

    2017-10-01

    Full Text Available Introduction Distribution of leaf area and dry matter are the effective factors that influence on absorption the radiation, evaporation and transpiration of canopy and eventually dry matter accumulation and grain yield in plants. Plant canopy is the spatial arrangement of shoots in a plant population. In plant canopy, leaves are responsible for radiation absorption and gas exchange with the outside. Stem and branches arrange photosynthetic organs somehow, which gas exchange and light distribution best done. The effect of canopy structure on gas exchange and absorption of radiation in plant communities caused detailed study of the canopy structure to be more important. Materials and methods In order to investigate the vertical distribution of leaf area and dry matter of borage and sweet basil in competition with weeds by cover crops treatments, a field experiment was carried out in a randomized complete block design with 8 treatments and 3 replications in Agricultural Sciences and Natural Resources University of Sari in 2013. Treatments were cover crops mung bean (Vigna radiata L. and Persian clover (Trifolium resupinatum L. in the rows between the sweet basil (Ocimum basilicum L. and borage (Borago officinalis L.. Moreover, in order to evaluate the effectiveness of cover crops to control weeds, pure stand of sweet basil and borage in terms of weeding and no weed controls per replicates were used. Each plot was included 5 rows of medicinal plants. Cover crop inter-seeded simultaneously in the main crop. Estimation of leaf area and dry matter of each plant in different canopy layers (0-20, 20-40, 40-60, 80.100, 100-120 and 120-140 cm were done after 75 planting days, with 1 m × 1 m quadrate per plot. For this purpose a vertical card board frame marked in 20-cm increments was used in the field as a guide to cut standing plants (crops, cover crops and weeds into 20-cm strata increments (Mosier & Oliver, 1995. All samples were transferred to the

  1. Mycorrhiza formation and nutrient concentration in leeks (¤Allium porrum¤) in relation to previous crop and cover crop management on high P soils

    DEFF Research Database (Denmark)

    Sørensen, J.N.; Larsen, J.; Jakobsen, I.

    2005-01-01

    An improved integration of mycorrhizas may increase the sustainability in plant production. Two strategies for increasing the soil inoculum potential of mycorrhizal fungi were investigated in field experiments with leeks: Pre-cropping with mycorrhizal main crops and pre-establishment of mycorrhiz...

  2. Cover crop with Teramnus labialis in a citrus orchard: effects on some physical properties of the soil / Cubierta vegetal con Teramnus labialis en plantaciones citrícolas: efectos sobre algunas propiedades físicas del suelo Cubierta vegetal con Teramnus labialis en plantaciones citrícolas: efectos sobre algunas propiedades físicas del suelo

    Directory of Open Access Journals (Sweden)

    Leydis Castellano Rodríguez

    2009-03-01

    Full Text Available The use of leguminous cover crops in citrus orchards constitutes a viable alternative for the improvement of soil properties, whenever they are appropriately managed. In Ciego de Avila University, Cuba, it was evaluated the effect of a leguminous cover crop on some properties of an orchard soil. The work was carried out during four years in an orange plantation of Valencia late (Citrus sinensis L. Osbeck in a 22 years-old orchard, with a plantation frame of 8 X 4 m, planted on a typical red Ferralitic soil, belonging to the CPA ¨José Martí¨, in Ciego de Avila. It was used a random block design with three treatments: one with covering of Teramnus labialis (T1, one with expontaneous vegetation (T2 and the third with no vegetation (T3. The functional structure properties of the soil were determined, and also the composition of macroaggregates expressed in the structure coefficient and the percentage of stable added in water, soil density, humidity and porosity. The increments in the humidity of the soil, the specific volume of pores and air, the structure coefficient, as well as the percentage of stable added in water, in the soil where the covering of Teramnus labialis was stablished, show the efficiency of cover crops in these citrus orchards.El uso de coberturas vivas de leguminosas en plantaciones citrícolas constituye una alternativa viable para el mejoramiento de las propiedades de los suelos, siempre que ellas se manejan adecuadamente en estas áreas. En la universidad de Ciego de Ávila, Cuba se viene trabajando en la evaluación del efecto de coberturas vivas de leguminosas en plantaciones citrícolas en producción, con el objetivo de evaluar el efecto que ejerce la cobertura de leguminosa sobre algunas propiedades del suelo. El trabajo se realizó durante cuatro años (2001-2005 en una plantación de naranja Valencia Late ( Citrus sinensis L. Osbeck en producción de 22 años, con marco de plantación de 8 X 4 m, plantada sobre un

  3. Regional variability of environmental effects of energy crop rotations

    Science.gov (United States)

    Prescher, Anne-Katrin; Peter, Christiane; Specka, Xenia; Willms, Matthias; Glemnitz, Michael

    2014-05-01

    The use of energy crops for bioenergy production is increasingly promoted by different frameworks and policies (ECCP, UNFCCC). Energy cropping decreases greenhouse gas emissions by replacing the use of fossil fuel. However, despite this, growing in monocultures energy crop rotations has low environmental benefit. It is broadly accepted consensus that sustainable energy cropping is only realizable by crop rotations which include several energy crop species. Four crop rotations consisting of species mixtures of C3, C4 and leguminous plants and their crop positions were tested to identify the environmental effect of energy cropping systems. The experimental design included four replicates per crop rotation each covering four cultivation years. The study took place at five sites across Germany covering a considerable range of soil types (loamy sand to silt loam), temperatures (7.5 ° C - 10.0 ° C) and precipitation (559 mm - 807 mm) which allow a regional comparison of crop rotation performance. Four indicators were used to characterize the environmental conditions: (1) greenhouse gas (GHG) emissions from the management actions; (2) change in humus carbon (Chum); (3) groundwater recharge (RGW) and (4) nitrogen dynamics. The indicators were derived by balance, by an empirical model and by a dynamic model, respectively, all based and calibrated on measured values. The results show that the crop rotation impact on environmental indicators varied between plant species mixtures and the crop positions, between sites and climate. Crop rotations with 100 % energy crops (including C4 plants) had negative influence on Chum, GHG emissions per area and RGW in comparison to the rotation of 50 % energy crops and 50 % cash crops, which were mainly due to the remaining straw on the field. However, the biogas yield of the latter rotation was smaller, thus GHG emissions per product were higher, pointing out the importance to distinguish between GHG emissions per product and per area

  4. High quality residues from cover crops favor changes in microbial community and enhance C and N sequestration

    Directory of Open Access Journals (Sweden)

    Ileana Frasier

    2016-04-01

    Full Text Available The objective of the study was to evaluate the effect of a change in management on the soil microbial community and C sequestration. We conducted a 3-year field study in La Pampa (Argentina with rotation of sorghum (Sorghum bicolor in zero tillage alternating with rye (Secale cereale and vetch (Vicia villosa ssp. dasycarpa. Soil was sampled once a year at two depths. Soil organic matter fractions, dissolved organic matter, microbial biomass (MBC and community composition (DNA extraction, qPCR, and phospholipid FAME profiles were determined. Litter, aerial- and root biomass were collected and all material was analyzed for C and N. Results showed a rapid response of microbial biomass to a bacterial dominance independent of residue quality. Vetch had the highest diversity index, while the fertilized treatment had the lowest one. Vetch–sorghum rotation with high N mineralization rates and diverse microbial community sequestered more C and N in stable soil organic matter fractions than no-till sorghum alone or with rye, which had lower N turnover rates. These results reaffirm the importance of enhanced soil biodiversity for maintaining soil ecosystem functioning and services. The supply of high amounts of N-rich residues as provided by grass–legume cover crops could fulfill this objective.

  5. PORE SIZE DISTRIBUTION AND SOIL HYDRO PHYSICAL PROPERTIES UNDER DIFFERENT TILLAGE PRACTICES AND COVER CROPS IN A TYPIC HAPLUSULT IN NORTHERN NIGERIA

    Directory of Open Access Journals (Sweden)

    Halima Mohammed Lawal

    2017-05-01

    Full Text Available Tillage practices influence soil physical, chemical and biological qualities which in-turn alters plant growth and crop yield. In the Northern Guinea Savanna (NGS ecological zone of Nigeria, agricultural production is mainly constrained by low soil nutrient and water holding capacity, it is therefore, imperative to develop appropriate management practices that will give optimal soil hydro-physical properties for proper plant growth, effective soil and water management and environmental conservation. This study investigated the effect of three tillage practices (no till, reduced till and conventional till and four cover crops (Centrosema pascuorum, Macrotyloma uniflorum, Cucurbita maxima and Glyine max and a bare/control (no cover crop on some soil physical properties of a Typic Haplusult during the rainy seasons of 2011, 2012 and 2013 in Samaru, NGS ecological zone of Nigeria. The field trials were laid out in a split plot arrangement with tillage practices in the main plots and cover crops in the subplots, all treatments were replicated three times. Auger and core soil samples were collected at the end of each cropping season each year in three replicates from each treatment plot at four depths (0-5, 5-10, 10-15 and 15-20 cm. Particle size distribution, bulk density, total pore volume and water retention at various soil matric potentials were determined using standard methods. Data obtained were compared with optimum values and fitted into a RETC computer code for quantifying soil hydraulic behavior and physical quality. Results showed that different tillage practices had varied effect on soil physical properties. No-till had the highest water holding capacity at most suction points evaluated, it had 4.3 % and 12.9 % more soil moisture than the reduced till  and conventionally tilled systems across all matric potentials while Centrosema pascuorum (3.1% and Cucurbita maxima (5.5% were best among evaluated cover crops in retaining soil moisture

  6. Notice of Release of US-1136, US-1137, and US-1138 Cowpea Gerplasm Lines with Potential For Use As A Cover Crop

    Science.gov (United States)

    In 1998, field screening trials were initiated to identify cowpea (Vigna unguiculata L.) populations suitable for use as a weed-suppressing cover crop. After the preliminary field studies, eleven populations were selected for more detailed evaluations. After three additional years of evaluation, e...

  7. Assessing the impacts of future climate conditions on the effectiveness of winter cover crops in reducing nitrate loads into the Chesapeake Bay Watersheds using SWAT model

    Science.gov (United States)

    Winter cover crops (WCCs) have been widely implemented in the Coastal Plain of the Chesapeake Bay watershed (CBW) due to their high effectiveness at reducing nitrate loads. However, future climate conditions (FCCs) are expected to exacerbate water quality degradation in the CBW by increasing nitrat...

  8. Assessing climate change impacts on winter cover crop nitrate uptake efficiency on the coastal plain of the Chesapeake Bay watershed using the SWAT model

    Science.gov (United States)

    Climate change is expected to exacerbate water quality degradation in the Chesapeake Bay watershed (CBW). Winter cover crops (WCCs) have been widely implemented in this region owing to their high effectiveness at reducing nitrate loads. However, little is known about climate change impacts on the ef...

  9. Effects of break crops, and of wheat volunteers growing in break crops or in set-aside or conservation covers, all following crops of winter wheat, on the development of take-all (Gaeumannomyces graminisvar.tritici) in succeeding crops of winter wheat.

    Science.gov (United States)

    Jenkyn, Jf; Gutteridge, Rj; White, Rp

    2014-11-01

    Experiments on the Rothamsted and Woburn Experimental Farms studied the effects on take-all of different break crops and of set-aside/conservation covers that interrupted sequences of winter wheat. There was no evidence for different effects on take-all of the break crops per se but the presence of volunteers, in crops of oilseed rape, increased the amounts of take-all in the following wheat. Severity of take-all was closely related to the numbers of volunteers in the preceding break crops and covers, and was affected by the date of their destruction. Early destruction of set-aside/conservation covers was usually effective in preventing damaging take-all in the following wheat except, sometimes, when populations of volunteers were very large. The experiments were not designed to test the effects of sowing dates but different amounts of take-all in the first wheats after breaks or covers apparently affected the severity of take-all in the following (second) wheats only where the latter were relatively late sown. In earlier-sown second wheats, take-all was consistently severe and unrelated to the severity of the disease in the preceding (first) wheats. Results from two very simple experiments suggested that substituting set-aside/conservation covers for winter wheat, for 1 year only, did not seriously interfere with the development of take-all disease or with the development or maintenance of take-all decline (TAD). With further research, it might be possible for growers wishing to exploit TAD to incorporate set-aside/conservation covers into their cropping strategies, and especially to avoid the worst effects of the disease on grain yield during the early stages of epidemics.

  10. Assessing the environmental impacts of cropping systems and cover crops : Life cycle assessment of FAST, a long-term arable farming field experiment

    NARCIS (Netherlands)

    Prechsl, U E; Wittwer, R; van der Heijden, M.G.A.; Luscher, G; Jeanneret, P; Nemecek, T

    2017-01-01

    To reduce environmental impacts of cropping systems, various management strategies are being discussed. Longterm field experiments are particularly suitable to directly compare different management strategies and to perform a comprehensive impact assessment. To identify the key drivers of several

  11. Diversity of root nodule bacteria from leguminous crops

    Directory of Open Access Journals (Sweden)

    Agrawal Pooja

    2016-01-01

    Full Text Available In the present study, a total of 353 nodule-associated bacteria were isolated from 220 legume plant samples belonging to Cicer arietinum (85, Glycine max (74, Vigna radiata (21 and Cajanus cajan (40. A total of 224 bacteria were identified as fast-growing Rhizobium spp. on the basis of differential staining (Gram staining and carbol fuchsin staining and biochemical tests. All the isolates were tested for indole acetic acid production (IAA, phosphate solubilization and siderophore production on plate assay. To examine the effect of volatile organic metabolites (VOM and water soluble soil components (WSSC on nodule bacteria, culture conditions were optimized by observing the effects of various parameters such as pH, salt content and temperatures on the growth of bacteria. Selected rhizobia were subjected to random amplified polymorphic DNA (RAPD and amplified ribosomal DNA restriction analysis (ARDRA analysis to identify their species. On the basis of RAPD and ARDRA, 10 isolates were identified as Rhizobium meliloti. In this study, Rhizobium GO4, G16, G20, G77, S43, S81, M07, M37, A15 and A55 were observed as the best candidates among the tested bacteria and can be further used as potent bioinoculants.

  12. Rotation of Maize with some Leguminous Food Crops for ...

    African Journals Online (AJOL)

    GMX 92–16-2M), bambara groundnut (Vigna subterranea (L.) Verd, var. Ada) and groundnut (Arachis hypogea L., var. goronga). The experimental treatments were: incorporated legume residues, recommended inorganic fertilizer application (100 kg N, 60 kg P O and 40 kg K SO ha-1) and no fertilization as 2 5 2 4 control.

  13. EFFECTS OF ATMOSPHERIC H2S ON THIOL COMPOSITION OF CROP PLANTS

    NARCIS (Netherlands)

    BUWALDA, F; DE KOK, LJ; Stulen, I.

    Exposure of crop plants to H2S resulted in an increase in thiol level and a change in the composition of the thiol pool. Non-leguminous species accumulated cysteine and glutathione in the light, whereas in the dark, substantial amounts of gamma-glutamyl-cysteine were also detected. In leguminous

  14. Plantas de cobertura de solo como hospedeiras alternativas de Colletotrichum guaranicola Cover crops as intermediate hosts to Colletotrichum guaranicola

    Directory of Open Access Journals (Sweden)

    L.J. Mileo

    2006-12-01

    Full Text Available As plantas de cobertura de solo usadas para suprimir o crescimento de plantas daninhas podem hospedar fungos fitopatogênicos. Para testar essa hipótese, elaborou-se este trabalho com o objetivo de avaliar o comportamento de nove espécies de plantas como possíveis hospedeiras do fungo Colletotrichum guaranicola. O experimento foi conduzido em casa de vegetação sob delineamento inteiramente casualizado, com quatro repetições. Cada vaso com três plantas da mesma espécie representou uma unidade experimental. As espécies que constituíram os tratamentos foram: Arachis pintoi, Calopogonium mucunoides, Chamaecrista rotundifolia, Crotalaria striata, Desmodium ovalifolium, Flemingia congesta, Mucuna aterrima, Pueraria phaseoloides e Tephrosia candida. Quarenta dias após a semeadura, as plantas foram inoculadas com suspensão de esporos de C. guaranicola na concentração de 10(5 conídios mL¹, enquanto as plantas testemunhas receberam somente água. As plantas foram mantidas em câmara úmida por 48 horas. Diariamente, foram feitas observações por 15 dias após a inoculação, para visualizar sintomas da doença. As espécies que não apresentaram sintomas de C. guaranicola foram Arachis pintoi, Chamaecrista rotundifolia, Desmodium ovalifolium, Flemingia congesta e Tephrosia candida, e as que manifestaram sintomas após a inoculação foram Calopogonium mucunoides, Crotalaria striata, Mucuna aterrima e Pueraria phaseoloides, que podem ser fontes de inóculo do patógeno da antracnose para o guaranazeiro.Cover crops used to suppress weed growth can be intermediate hosts to phytopathogenic fungi. To test this hypothesis, nine species of cover crops were evaluated as hosts to Colletotrichum guaranicola. The experiment was arranged in a randomized design, with four replicates, and conducted under greenhouse conditions. Each vase with three plants of one species constituted one plot. The species treated were: Arachis pintoi, Calopogonium

  15. Migration and Enrichment of Arsenic in the Rock-Soil-Crop Plant System in Areas Covered with Black Shale, Korea

    Directory of Open Access Journals (Sweden)

    Ji-Min Yi

    2003-01-01

    Full Text Available The Okchon black shale, which is part of the Guryongsan Formation or the Changri Formation of Cambro-Ordovician age in Korea provides a typical example of natural geological materials enriched with potentially toxic elements such as U, V, Mo, As, Se, Cd, and Zn. In this study, the Dukpyung and the Chubu areas were selected to investigate the migration and enrichment of As and other toxic elements in soils and crop plants in areas covered with black shale. Rock and soil samples digested in 4-acid solution (HCl+HNO3+HF+HClO4 were analyzed for As and other heavy metals by ICP-AES and ICP-MS, and plant samples by INAA. Mean concentration of As in Okchon black shale is higher than those of both world average values of shale and black shale. Especially high concentration of 23.2 mg As kg-1 is found in black shale from the Dukpyung area. Mean concentration of As is highly elevated in agricultural soils from the Dukpyung (28.2 mg kg-1 and the Chubu areas (32.6 mg kg-1. As is highly elevated in rice leaves from the Dukpyung (1.14 mg kg-1 and the Chubu areas (1.35 mg kg-1. The biological absorption coefficient (BAC of As in plant species decreases in the order of rice leaves > corn leaves > red pepper = soybean leaves = sesame leaves > corn stalks > corn grains. This indicates that leafy plants tend to accumulate As from soil to a greater degree than cereal products such as grains.

  16. Integrating high residue cover crops and weed control options for resistant weeds threatening conservation agriculture and water resources

    Science.gov (United States)

    Conservation tillage reduces the physical movement of soil to the minimum required for crop establishment and production. When consistently practiced as a soil and crop management system, it greatly reduces soil erosion and is recognized for the potential to improve soil quality and plant water avai...

  17. The influence of cover crops and tillage on actual and potential soil erosion in an olive grove

    Science.gov (United States)

    Sastre, Blanca; Bienes, Ramón; García-Díaz, Andrés; Panagopoulos, Thomas; José Marqués, Maria

    2014-05-01

    The study was carried out in an olive grove in central Spain (South of Madrid; Tagus River Basin). In this semi-arid zone, the annual mean temperature is 13.8 ºC and the annual precipitation is 395 mm. Olive groves are planted in an erosion prone area due to steep slopes up to 15%. Soil is classified as Typic Haploxerept with clay loam texture. The land studied was formerly a vineyard, but it was replaced by the studied olive grove in 2004. It covers approximately 3 ha and olive trees are planted every 6 x 7 metres. They were usually managed by tillage to decrease weed competition. This conventional practice results in a wide surface of bare soil prone to erosion processes. In the long term soil degradation may lead to increase the desertification risk in the area. Storms have important consequences in this shallow and vulnerable soil, as more than 90 Mg ha-1 have been measured after one day with 40 mm of rainfall. In order to avoid this situation, cover crops between the olive trees were planted three years ago: sainfoin (Onobrychis viciifolia), barley (Hordeum vulgare), and purple false brome (Brachypodium distachyon), and they were compared with annual spontaneous vegetation after a minimum tillage treatment (ASV). The results regarding erosion control were positive. We observed (Oct. 2012/Sept. 2013) annual soil loss up to 11 Mg ha-1 in ASV, but this figure was reduced in the sown covers, being 8 Mg ha-1 in sainfoin treatment, 3,7 Mg ha-1 in barley treatment, and only 1,5 Mg ha-1 in false brome treatment. Those results are used to predict the risk of erosion in long term. Moreover, soil organic carbon (SOC) increased with treatments, this is significant as it reduces soil erodibility. The increases were found both in topsoil (up to 5 cm) and more in depth, in the root zone (from 5 to 10 cm depth). From higher to lower SOC values we found the false brome (1.05%), barley (0.92%), ASV (0.79%) and sainfoin (0.71%) regarding topsoil. In the root zone (5-10 cm depth

  18. Energy efficiency for establishment and management of cover crops; Eficiencia energetica na implantacao e manejo de plantas de cobertura do solo

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, R.; Gamero, C.A.; Boller, W.

    2000-07-01

    An experiment was conducted in Botucatu, SP, Brazil to evaluate the energy balance involved in the establishment and management of cover crops and also to determine specific heating seeds and biomass of different species of cover crops. Black oat (Avena strigosa Schreb), forage radish (Raphanus sativus L. var. oleiferus Metzg) and lupinus (Lupinus angustifolius L.) were grown in a randomized block design, in twelve replicates. Oat showed higher energy production as compared to lupinus, while higher specific heat were determined for forage radish seeds and also for lupinus and oat biomass. While fuel and fertilizers were the most important energy inputs for the establishment and management of oat and forage radish, seeds and fuel were the most used energy input for lupinus. (author)

  19. Herbicide and cover crop residue integration for amaranth control in conservation agriculture cotton and implications for resistance management

    Science.gov (United States)

    Conservation agriculture practices are threatened by glyphosate-resistant Palmer amaranth. Integrated practices including PRE herbicides and high-residue conservation agriculture systems may decrease Amaranth emergence. Field experiments were conducted from autumn 2006 through cash crop harvest in...

  20. The suitability of non-legume cover crops for inorganic soil nitrogen immobilisation in the transition period to an organic no-till system

    Directory of Open Access Journals (Sweden)

    Lars Rühlemann

    2016-01-01

    Full Text Available The aim of the study was to evaluate non-legume cover crops for growing no-till grain legumes in organic farming systems. Evaluated cover crops should be able to suppress weed growth, reduce plant available nitrogen in the soil and produce large amounts of biomass with slow N mineralisation. Six non-legume species; spring rye (Secale cereale L., black oat (Avena sativa L., sunflower (Helianthus annuus L., white mustard (Sinapis alba L., buckwheat (Fagopyrum esculentum Moench and hemp (Cannabis sativa L. were tested. Plots with organic fertiliser (50 kg N ha−1 and without fertiliser incorporation at three locations in south-east Germany were trialled and the cover crops’ ability to produce biomass and accumulate N in plant compartments was evaluated. The N mineralisation from stem and leaf material was simulated using the STICS model. The biomass production ranged from 0.95 to 7.73 Mg ha−1, with fertiliser increasing the total biomass at locations with low-N status. Sunflower consistently displayed large biomass and N accumulation at all locations and fertiliser variations, although not always significantly more than other species. Most N was stored in sunflower leaf material, which can be easily mineralised making it less suited as cover crop before no-till sown spring grain legumes. Rye, which produced slightly less biomass, but accumulated more N in the stem biomass, would be better suited than sunflower in this type of system. The N mineralisation simulation from rye biomass indicated long N immobilisation periods potentially improving weed suppression within no-till sown legume cash crops.

  1. Overland flow connectivity in olive orchard plots with cover crops and conventional tillage, and under different rainfall scenarios

    Science.gov (United States)

    López-Vicente, Manuel; García-Ruiz, Roberto; Guzmán, Gema; Vicente-Vicente, José Luis; Gómez, José Alfonso

    2016-04-01

    The study of overland flow connectivity (QC) allows understanding the redistribution dynamics of runoff and soil components as an emergent property of the spatio-temporal interactions of hydrological and geomorphic processes. However, very few studies have dealt with runoff connectivity in olive orchards. In this study we simulated QC in four olive orchard plots, located on the Santa Marta farm (37° 20' 33.6" N, 6° 13' 44" W), in Seville province (Andalusia) in SW Spain. The olive plantation was established in 1985 with trees planted at 8 m x 6 m. Each bounded plot is 8 m wide (between 2 tree lines) and 60 m long (total area of 480 m2), laid out with the longest dimension parallel to the maximum slope and to the tree lines. The slope is uniform, with an average steepness of 11%. Two plots (P2 and P4) were devoted to conventional tillage (CT) consisting of regular chisel plow passes depending on weed growth. Another set of two plots had two types of cover crops (CC) in the inter tree rows (the area outside the vertical olive canopy projection): uniform CC of Lolium multiflorum (P3) and a mixture of L. rigidum and L. multiflorum together with other species (P5). The tree rows were treated with herbicide to keep bare soil. We selected the Index of runoff and sediment Connectivity (IC) of Borselli et al. (2008) to simulate three rainfall scenarios: i) low rainfall intensity (Sc-LowInt) and using the MD flow accumulation algorithm; ii) moderate rainfall intensity (Sc-ModInt) and using MD8; and iii) high rainfall intensity (Sc-HighInt) and using D8. After analysing the values of rainfall intensity during two hydrological years (Oct'09-Sep'10 and Oct'10-Sep'11) we associated the three scenarios with the followings months: Sc-LowInt during the period Jan-Mar, that summarizes 42% of all annual rainfall events; Sc-ModInt during Oct-Nov and Apr-May (32% of all events); and Sc-HighInt during the period Jun-Sep and in December (26% of all events). Instead of using the C

  2. Assessment of the AquaCrop model for use in simulation of irrigated winter wheat canopy cover, biomass, and grain yield in the North China Plain.

    Directory of Open Access Journals (Sweden)

    Xiu-liang Jin

    Full Text Available Improving winter wheat water use efficiency in the North China Plain (NCP, China is essential in light of current irrigation water shortages. In this study, the AquaCrop model was used to calibrate, and validate winter wheat crop performance under various planting dates and irrigation application rates. All experiments were conducted at the Xiaotangshan experimental site in Beijing, China, during seasons of 2008/2009, 2009/2010, 2010/2011 and 2011/2012. This model was first calibrated using data from 2008/2009 and 2009/2010, and subsequently validated using data from 2010/2011 and 2011/2012. The results showed that the simulated canopy cover (CC, biomass yield (BY and grain yield (GY were consistent with the measured CC, BY and GY, with corresponding coefficients of determination (R(2 of 0.93, 0.91 and 0.93, respectively. In addition, relationships between BY, GY and transpiration (T, (R(2 = 0.57 and 0.71, respectively was observed. These results suggest that frequent irrigation with a small amount of water significantly improved BY and GY. Collectively, these results indicate that the AquaCrop model can be used in the evaluation of various winter wheat irrigation strategies. The AquaCrop model predicted winter wheat CC, BY and GY with acceptable accuracy. Therefore, we concluded that AquaCrop is a useful decision-making tool for use in efforts to optimize wheat winter planting dates, and irrigation strategies.

  3. Assessment of the AquaCrop model for use in simulation of irrigated winter wheat canopy cover, biomass, and grain yield in the North China Plain.

    Science.gov (United States)

    Jin, Xiu-liang; Feng, Hai-kuan; Zhu, Xin-kai; Li, Zhen-hai; Song, Sen-nan; Song, Xiao-yu; Yang, Gui-Jun; Xu, Xin-gang; Guo, Wen-shan

    2014-01-01

    Improving winter wheat water use efficiency in the North China Plain (NCP), China is essential in light of current irrigation water shortages. In this study, the AquaCrop model was used to calibrate, and validate winter wheat crop performance under various planting dates and irrigation application rates. All experiments were conducted at the Xiaotangshan experimental site in Beijing, China, during seasons of 2008/2009, 2009/2010, 2010/2011 and 2011/2012. This model was first calibrated using data from 2008/2009 and 2009/2010, and subsequently validated using data from 2010/2011 and 2011/2012. The results showed that the simulated canopy cover (CC), biomass yield (BY) and grain yield (GY) were consistent with the measured CC, BY and GY, with corresponding coefficients of determination (R(2)) of 0.93, 0.91 and 0.93, respectively. In addition, relationships between BY, GY and transpiration (T), (R(2) = 0.57 and 0.71, respectively) was observed. These results suggest that frequent irrigation with a small amount of water significantly improved BY and GY. Collectively, these results indicate that the AquaCrop model can be used in the evaluation of various winter wheat irrigation strategies. The AquaCrop model predicted winter wheat CC, BY and GY with acceptable accuracy. Therefore, we concluded that AquaCrop is a useful decision-making tool for use in efforts to optimize wheat winter planting dates, and irrigation strategies.

  4. Crop residues as driver for N2O emissions from a sandy loam soil

    DEFF Research Database (Denmark)

    Pugesgaard, Siri; Petersen, Søren O.; Chirinda, Ngonidzashe

    2017-01-01

    -term experiment on a loamy sand soil at Foulum in Denmark. All cropping systems included winter wheat, a leguminous crop (faba bean or grass-clover), potato and spring barley grown in different 4-crop rotations varying in strategies for N supply (fertilizer/manure type and rate, use of catch crops and green...

  5. Nitrogen-fixing bacteria associated with leguminous and non-leguminous plants

    OpenAIRE

    Franche, Claudine; Lindstrom, K.; Elmerich, C.

    2009-01-01

    Nitrogen is generally considered one of the major limiting nutrients in plant growth. The biological process responsible for reduction of molecular nitrogen into ammonia is referred to as nitrogen fixation. A wide diversity of nitrogen-fixing bacterial species belonging to most phyla of the Bacteria domain have the capacity to colonize the rhizosphere and to interact with plants. Leguminous and actinorhizal plants can obtain their nitrogen by association with rhizobia or Frankia via different...

  6. The effect of plant growth promoting rhizobacteria (PGPR on quantitative and qualitative characteristics of Sesamum indicum L. with application of cover crops of Lathyrus sp. and Persian clover (Trifolium resopinatum L.

    Directory of Open Access Journals (Sweden)

    M. Jahan

    2016-05-01

    Full Text Available Cover crops cultivation and application of plant growth rhizobacteria are the key factors to enhance agroecosystem health. A field experiment was conducted at the Research Farm of Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, during growing season of 2009-2010. A split plot arrangement based on a complete randomized block design with three replications was used. Cultivation and no cultivation of Lathyrus sp. and Persian clover (Trifolium resopinatum in autumn assigned to the main plots. The sub plot factor consisted of three different types of biofertilizers plus control, including 1-nitroxin (containing of Azotobacter sp. and Azospirillum sp., 2- phosphate solubilizing bacteria (PSB (containing of Bacillus sp. and Pseudomonas sp., 3- biosulfur (containing of Thiobacillus ssp. and 4- control (no fertilizer. The results showed the effect of cover crops on seed number and seed weight per plant, biological and seed yield was significant, as the seed yield increased of 9 %. In general, biofertilizers showed superiority due to the most studied traits compared to control. Nitroxin, PSB and biosulfur increased biological yield of 44, 28 and 26 % compared to control, respectively. Cover crops and biofertilizers interactions, showed significant effect on all studied traits, as the highest and the lowest harvest index resulted in cover crop combined with biofertilizers (22.1% and cultivation and no cultivation of cover crops combined with control (15.3%, respectively. The highest seed oil and protein content resulted from cover crops plus biofertilizers (42.4% and cover crops plus PSB (22.5%, respectively. In general, the results showed cover crops cultivation in combination with biofertilizers application could be an ecological alternative for chemical fertilizers, in addition of achieving advantages of cover crops. According to the results, it should be possible to design an ecological cropping system and produce appropriate and healthy

  7. Cover crop rotations in no-till system: short-term CO2 emissions and soybean yield

    Directory of Open Access Journals (Sweden)

    João Paulo Gonsiorkiewicz Rigon

    Full Text Available ABSTRACT: In addition to improving sustainability in cropping systems, the use of a spring and winter crop rotation system may be a viable option for mitigating soil CO2 emissions (ECO2. This study aimed to determine short-term ECO2 as affected by crop rotations and soil management over one soybean cycle in two no-till experiments, and to assess the soybean yields with the lowest ECO2. Two experiments were carried out in fall-winter as follows: i triticale and sunflower were grown in Typic Rhodudalf (TR, and ii ruzigrass, grain sorghum, and ruzigrass + grain sorghum were grown in Rhodic Hapludox (RH. In the spring, pearl millet, sunn hemp, and forage sorghum were grown in both experiments. In addition, in TR a fallow treatment was also applied in the spring. Soybean was grown every year in the summer, and ECO2 were recorded during the growing period. The average ECO2 was 0.58 and 0.84 g m2 h–1 with accumulated ECO2 of 5,268 and 7,813 kg ha–1 C-CO2 in TR and RH, respectively. Sunn hemp, when compared to pearl millet, resulted in lower ECO2 by up to 12 % and an increase in soybean yield of 9% in TR. In RH, under the winter crop Ruzigrazz+Sorghum, ECO2 were lower by 17%, although with the same soybean yield. Soil moisture and N content of crop residues are the main drivers of ECO2 and soil clay content seems to play an important role in ECO2 that is worthy of further studies. In conclusion, sunn hemp in crop rotation may be utilized to mitigate ECO2 and improve soybean yield.

  8. Distribution of isoflavonoids in non-leguminous taxa - an update.

    Science.gov (United States)

    Mackova, Zuzana; Koblovska, Radka; Lapcik, Oldrich

    2006-05-01

    Common emphasis of the fact that isoflavonoids are characteristic metabolites of leguminous plants sometimes leads to overlooking that the presence of isoflavonoids has been reported in several dozen other families. The spectrum of isoflavonoid producing taxa includes the representatives of four classes of multicellular plants, namely the Bryopsida, the Pinopsida, the Magnoliopsida and the Liliopsida. A review, recently published by Reynaud et al. [Reynaud, J., Guilet D., Terreux R., Lussignol M., Walchshofer N., 2005. Isoflavonoids in non-leguminous families: an update. Nat. Prod. Rep. 22, 504-515], provided listing of 164 isoflavonoids altogether reported in 31 non-leguminous angiosperm families. In this contribution we complement the abovementioned inventory bringing the references on further 17 isoflavonoid producing families and on additional 49 isoflavonoids reported to occur in non-leguminous plants.

  9. Herbicide and cover crop residue integration for amaranthus control in conservation agriculture cotton and implications for resistance management

    Science.gov (United States)

    Conservation agriculture (CA) practices are threatened by glyphosate-resistant Palmer amaranth. Integrated control practices including PRE herbicides and high-residue CA systems can decrease Amaranthus emergence. Field experiments were conducted from autumn 2006 through crop harvest in 2009 at two s...

  10. Impact of broadcasting a cereal rye or oat cover crop before corn and soybean harvest on nitrate leaching

    Science.gov (United States)

    The corn and soybean rotation in Iowa has no living plants taking up water and nutrients from crop maturity until planting, a period of over six months in most years. In many fields, this results in losses of nitrate in effluent from artificial drainage systems during this time. In a long-term fiel...

  11. Effects of earthworms on soil aggregate stability and carbon and nitrogen storage in a legume cover crop agroecosystem.

    NARCIS (Netherlands)

    Ketterings, Q.M.; Blair, J.M.; Marinissen, J.C.Y.

    1997-01-01

    We investigated the effects of earthworms on soil aggregate size-distribution, water-stability, and the distribution of total C and N among aggregates of different sizes. Earthworm populations were experimentally manipulated (reduced, unaltered or increased) in field enclosures cropped to soybean

  12. User-inspired Research Quantifies How Floodplain Restoration Paired With Cover Crops Reduces Nutrient Export From an Agricultural Catchment Translating to Conservation Success in the Midwestern Cornbelt.

    Science.gov (United States)

    Tank, J. L.; Hanrahan, B.; Christopher, S. F.; Mahl, U. H.; Royer, T. V.

    2017-12-01

    The Midwestern US has undergone extensive land use change as forest, wetlands, and prairies have been converted to agroecosystems. Today, excess fertilizer nutrients from farm fields enter agricultural streams, which degrades both local and downstream water quality. We are quantifying the nutrient reduction benefits of two conservation practices implemented at the catchment scale. In partnership with The Nature Conservancy, in a small Indiana catchment, we have quantified how 600m of floodplain restoration (i.e., a two-stage ditch) increased nitrate-N removal via denitrification and reduced sediment export, but impacts on stream nutrient concentrations were negligible due to very high catchment loading relative to the short implementation reach. Requests from state and federal partners led to development and parameterization of a new two-stage ditch module in the SWAT model to determine the potential catchment-scale benefits when implementation lengths were extended. More recently, in partnership with state SWCD managers, we have added a landscape practice to quantify how winter cover crops reduce nutrient loss from fields, sampling year-round nutrient fluxes from multiple subsurface tile drains and longitudinally along the stream channel. Nitrate-N and dissolved P fluxes were significantly lower in tiles draining fields with cover crops compared to those without. At the urging of farmers and federal NRCS partners, we also linked tile drain nutrient reductions to changes in soil chemistry. Both soil nitrate-N and dissolved P were lower in cover cropped fields, and we found significant correlations between soil and tile drain nutrients, which may encourage future adoption of the conservation practice as soil health benefits appeal to farmers. As biogeochemists, this research has provided valuable insights on how floodplains and land cover change can alter patterns of catchment-scale nutrient export. The translation of successful soil and water quality outcomes

  13. Culturas de cobertura e qualidade física de um Latossolo em plantio direto Cover crops and physical quality of a Latosol under no-tillage

    Directory of Open Access Journals (Sweden)

    Rui da S. Andrade

    2009-08-01

    Full Text Available Com este trabalho se objetivou determinar o efeito de culturas de cobertura na qualidade física de um Latossolo Vermelho distrófico em plantio direto. O experimento foi irrigado por pivô central e conduzido na Embrapa Arroz e Feijão, em Santo Antônio de Goiás, GO, no delineamento de blocos ao acaso, com oito repetições. Os tratamentos consistiram de oito culturas de cobertura: braquiária; milho consorciado com braquiária; guandu anão; milheto; mombaça; sorgo; estilosantes e crotalária. As sete primeiras vêm sendo cultivadas no verão desde dezembro de 2001 e a crotalária a partir de novembro de 2003. No inverno de cada ano e após dessecação dessas culturas, foi implantado o feijoeiro irrigado e, em fevereiro de 2006, determinados o conteúdo de matéria orgânica do solo, alguns atributos físicos e sua qualidade física, por meio do índice S. As culturas de cobertura, especialmente as gramíneas, favoreceram a agregação do solo na camada superficial. O cultivo do solo modificou a sua estrutura comparativamente à mata nativa, aumentando sua densidade e reduzindo a macroporosidade, porosidade total e qualidade física. Entre as culturas de cobertura guandu, crotalária e milho consorciado com braquiária, foram as que mantiveram a camada superficial do solo com boa qualidade física.The objective of this study was to determine the effect of cover crop mulches on the physical quality of a distrophic Red Latosol (Oxisol under no-tillage. The experiment was carried out under center pivot at Embrapa Rice & Beans, in Santo Antônio de Goiás, GO, in a randomized block design, with eight replications. The treatments consisted of eight cover crops: Brachiaria brizantha; corn associated with B. brizantha; pigeon pea; millet; Panicum maximum; sorghum; Stylosanthes guianensis; and Crotalaria juncea. The first seven crops had been cultivated in summer season since December 2001 and C. juncea since November 2003. In the winter season

  14. Improvement of soil carbon sink by cover crops in olive orchards under semiarid conditions. Influence of the type of soil and weed

    Directory of Open Access Journals (Sweden)

    F. Márquez-García

    2013-05-01

    Full Text Available The olive tree is one of the most important crops in Spain, and the main one in the region of Andalusia. Most orchards are rain-fed, with high slopes where conventional tillage (CT is the primary soil management system used. These conditions lead to high erosion and a significant transport of organic carbon (OC. Moreover, soil tillage accelerates the oxidation of the OC. Cover crops (CC are the conservation agriculture (CA approach for woody crops. They are grown in-between tree rows to protect the soil against water erosion and their organic residues also help to increase the soil carbon (C sink. Soil and OC losses associated to the sediment were measured over four seasons (2003-07 using micro-plots for the collection of runoff and sediment in five experimental fields located in rain-fed olive orchards in Andalusia. Two soil management systems were followed, CC and CT. Furthermore, the changes in soil C in both systems were analyzed at a depth of 0-25 cm. CC reduced erosion by 80.5%, and also OC transport by 67.7%. In addition, Cover crops increased soil C sink by 12.3 Mg ha-1 year-1 of carbon dioxide (CO2 equivalent, with respect to CT. CC in rainfed olive orchards in a Mediterranean climate could be an environmental friendly and profitable system for reducing erosion and increasing the soil C sink. However, C fixing rate is not regular, being very high for the initial years after shifting from CT to CC and gradually decreasing over time.

  15. Manejo de plantas de cobertura no controle de plantas daninhas na cultura do milho Cover crop management and weed control in corn

    Directory of Open Access Journals (Sweden)

    P.V.D. Moraes

    2009-06-01

    Full Text Available O sistema de semeadura direta na cultura do milho tem apresentado expansão na região Sul do Brasil. A escolha adequada de espécies de cobertura, associada ao manejo em pré-semeadura da cobertura, pode intensificar o efeito alelopático sobre plantas daninhas. Foi avaliada a adaptabilidade de espécies vegetais e os efeitos alelopáticos, associados às práticas de manejo da cobertura e ao uso de herbicida pós-emergente, no controle de plantas daninhas na cultura do milho. O delineamento experimental utilizado foi em blocos ao acaso, com quatro repetições. Os tratamentos foram: espécies de cobertura, manejo das coberturas e aplicação ou não de herbicida em pós-emergência. As variáveis avaliadas foram: porcentagem de cobertura, matéria seca da cobertura, número de plantas daninhas, além de estatura, área foliar, matéria seca de plantas de milho e produtividade de grãos. As espécies nabo forrageiro e azevém apresentaram maior cobertura do solo. A cobertura de azevém proporciona maior redução de plantas daninhas e maior crescimento de plantas de milho. A dessecação das culturas de cobertura com glyphosate e paraquat, em geral, reduz o número de plantas daninhas e favorece o crescimento da cultura do milho. A influência do manejo da cobertura de solo na produtividade de grãos depende da espécie utilizada. A aplicação do herbicida nicosulfuron aumentou a produtividade do milho, independentemente da cultura de cobertura ou do manejo adotado.No-till planting system in corn cropping is widely used in southern Brazil. Adequate choice of cover species, associated to cover pre-sowing management, can intensify the allelopathic effect over weed plants. Adaptability of plant species and their allelopathic effects were evaluated, associated to management practices of cover crops and use of pre-emergent herbicide to control weeds in corn. The experimental design consisted of complete randomized blocks, with 4 replications

  16. Classification of rare land cover types: Distinguishing annual and perennial crops in an agricultural catchment in South Korea

    OpenAIRE

    Bogner, Christina; Seo, Bumsuk; Rohner, Dorian; Reineking, Björn

    2018-01-01

    Many environmental data are inherently imbalanced, with some majority land use and land cover types dominating over rare ones. In cultivated ecosystems minority classes are often the target as they might indicate a beginning land use change. Most standard classifiers perform best on a balanced distribution of classes, and fail to detect minority classes. We used the synthetic minority oversampling technique (smote) with Random Forest to classify land cover classes in a small agricultural catc...

  17. Changes In Soil Properties Under Alley Cropping System Of Three ...

    African Journals Online (AJOL)

    A study to evaluate the changes in soil properties, under existing alley cropping system with three leguminous crops (Leucaena leucocephala, Gliricidia sepium, and Cajanus cajan) was conducted in the experimental farm of the Faculty of Agriculture and Natural Resources Management, Ebonyi State University, Abakaliki ...

  18. Synergistic Effects of Agronet Covers and Companion Cropping on Reducing Whitefly Infestation and Improving Yield of Open Field-Grown Tomatoes

    Directory of Open Access Journals (Sweden)

    Stella Mutisya

    2016-09-01

    Full Text Available Tomatoes (Lycopersicon esculentum Mill are one of the biggest vegetable crops in the world, supplying a wide range of vitamins, minerals and fibre in human diets. In the tropics, tomatoes are predominantly grown under sub-optimal conditions by subsistence farmers, with exposure to biotic and abiotic stresses in the open field. Whitefly (Bemisia tabaci Gennadius is one of the major pests of the tomato, potentially causing up to 100% yield loss. To control whitefly, most growers indiscriminately use synthetic insecticides which negatively impact the environment, humans, and other natural pest management systems, while also increasing cost of production. This study sought to investigate the effectiveness of agronet covers and companion planting with aromatic basil (Ocimum basilicum L. as an alternative management strategy for whitefly in tomatoes and to evaluate the use of these treatments ontomato growth and yield. Two trials were conducted at the Horticulture Research and Training Field, Egerton University, Njoro, Kenya. Treatments comprised a combination of two factors, (1 growing environment (agronet and no agronet and (2 companion planting with a row of basil surrounding tomato plants, a row of basil in between adjacent rows of tomato, no companion planting. Agronet covers and companion cropping with a row of basil planted between adjacent tomato rows significantly lowered B. tabaci infestation in tomatoes by 68.7%. Better tomato yields were also recorded in treatments where the two treatments were used in combination. Higher yield (13.75 t/ha was obtained from tomatoes grown under agronet cover with a basil row planted in between adjacent rows of the tomato crop compared to 5.9 t/ha in the control. Non-marketable yield was also lowered to5.9 t/ha compared to 9.8 t/ha in the control following the use of the two treatments in combination. The results of this study demonstrate the potential viability of using companion cropping and agronet

  19. EVALUACION DE CUBIERTAS VEGETALES ("COVER CROPS") EN VINEDOS: EFECTOS DE LA NUTRICION, ESTADO HIDRICO DE LA VID Y SU RELACION CON LA PRODUCCION DE UVA Y CALIDAD DEL VINO.

    OpenAIRE

    Carlos Francisco Ovalle Molina; Alejandro Humberto Del Pozo Lira; Jorge Arturo Lavin Acevedo; Karla Canales Espinoza; Manuel Jesús Navarrete Fernández; Víctor Manuel Pérez Loyola

    2005-01-01

    EVALUATION OF COVER CROPS IN VINEYARDS: EFFECTS OF NUTRITION, WATER CONDITION OF THE VINE AND THEIR RELATIONSHIP TO GRAPE PRODUCTION AND WINE QUALITY Cover crops are used worldwide on vines as a sustainable method for soil management. This method is presumed to improve soil fertility conditions, particularly nitrogen contributions from leguminosae grown between rows, and also to enhance physical properties, avoid erosion, and reduce weeds. All of the above does not damage nor has harmful ...

  20. Hydrogen Reactions of Nodulated Leguminous Plants

    Science.gov (United States)

    Schubert, Karel R.; Engelke, Jean A.; Russell, Sterling A.; Evans, Harold J.

    1977-01-01

    The ATP-dependent evolution of H2 catalyzed by nitrogenase and the hydrogenase-catalyzed oxidation of H2 have been implicated as factors influencing the efficiency of energy utilization in the N2 fixation process. The effects of rhizobial strain and plant age on the H2-evolving and H2-utilizing activity of leguminous root nodules are described in this manuscript. Two classes of legume-Rhizobium combinations were observed in studies with soybeans (Glycine max L. Merr.) and cowpeas (Vigna unguiculata L. Walp.). One group evolved H2 in air; the other group did not exhibit net evolution of H2. The latter group metabolized H2 formed within the nodule through the action of a hydrogenase. The capacity to oxidize H2 was strongly linked to the strain of Rhizobium used to inoculate cowpeas and soybeans. Although the magnitude of H2 evolution in air changed during vegetative growth of a given symbiont, the ratio of H2 evolved in air to total nitrogenase activity was not appreciably altered during this period. No consistent difference in nitrogenase activity as measured by the C2H2 reduction assay was observed between symbionts with an active hydrogenase and those that apparently lack the enzyme and evolve H2. The effects of the two reactions of H2 on total N2 fixation and yield must now be established. PMID:16660157

  1. Comparison of DNDC and RZWQM2 for simulating hydrology and nitrogen dynamics in a corn-soybean system with a winter cover crop

    Science.gov (United States)

    Desjardins, R.; Smith, W.; Qi, Z.; Grant, B.; VanderZaag, A.

    2017-12-01

    Biophysical models are needed for assessing science-based mitigation options to improve the efficiency and sustainability of agricultural cropping systems. In order to account for trade-offs between environmental indicators such as GHG emissions, soil C change, and water quality it is important that models can encapsulate the complex array of interrelated biogeochemical processes controlling water, nutrient and energy flows in the agroecosystem. The Denitrification Decomposition (DNDC) model is one of the most widely used process-based models, and is arguably the most sophisticated for estimating GHG emissions and soil C&N cycling, however, the model simulates only simple cascade water flow. The purpose of this study was to compare the performance of DNDC to a comprehensive water flow model, the Root Zone Water Quality Model (RZWQM2), to determine which processes in DNDC may be limiting and recommend improvements. Both models were calibrated and validated for simulating crop biomass, soil hydrology, and nitrogen loss to tile drains using detailed observations from a corn-soybean rotation in Iowa, with and without cover crops. Results indicated that crop yields, biomass and the annual estimation of nitrogen and water loss to tiles drains were well simulated by both models (NSE > 0.6 in all cases); however, RZWQM2 performed much better for simulating soil water content, and the dynamics of daily water flow (DNDC: NSE -0.32 to 0.28; RZWQM2: NSE 0.34 to 0.70) to tile drains. DNDC overestimated soil water content near the soil surface and underestimated it deeper in the profile which was presumably caused by the lack of a root distribution algorithm, the inability to simulate a heterogeneous profile and lack of a water table. We recommend these improvements along with the inclusion of enhanced water flow and a mechanistic tile drainage sub-model. The accurate temporal simulation of water and N strongly impacts several biogeochemical processes.

  2. Effect of leguminous lectins on the growth of Rhizobium tropici CIAT899.

    Science.gov (United States)

    de Vasconcelos, Mayron Alves; Cunha, Cláudio Oliveira; Arruda, Francisco Vassiliepe Sousa; Carneiro, Victor Alves; Bastos, Rafaela Mesquita; Mercante, Fábio Martins; do Nascimento, Kyria Santiago; Cavada, Benildo Sousa; dos Santos, Ricardo Pires; Teixeira, Edson Holanda

    2013-05-17

    Rhizobium tropici is a Gram-negative bacterium that induces nodules and fixed atmospheric nitrogen in symbiotic association with Phaseolus vulgaris (common bean) and some other leguminous species. Lectins are proteins that specifically bind to carbohydrates and, consequently, modulate different biological functions. In this study, the d-glucose/ d-mannose-binding lectins (from seeds of Dioclea megacarpa, D. rostrata and D. violacea) and D-galactose-binding lectins (from seeds of Bauhinia variegata, Erythina velutina and Vatairea macrocarpa) were purified using chromatographic techniques and evaluated for their effect on the growth of R. tropici CIAT899. All lectins were assayed with a satisfactory degree of purity according to SDS-PAGE analysis, and stimulated bacterial growth; in particular, the Dioclea rostrata lectin was the most active among all tested proteins. As confirmed in the present study, both d-galactose- and d-glucose/d-mannose-binding lectins purified from the seeds of leguminous plants may be powerful biotechnological tools to stimulate the growth of R. tropici CIAT99, thus improving symbiotic interaction between rhizobia and common bean and, hence, the production of this field crop.

  3. Effect of Leguminous Lectins on the Growth of Rhizobium tropici CIAT899

    Directory of Open Access Journals (Sweden)

    Mayron Alves de Vasconcelos

    2013-05-01

    Full Text Available Rhizobium tropici is a Gram-negative bacterium that induces nodules and fixed atmospheric nitrogen in symbiotic association with Phaseolus vulgaris (common bean and some other leguminous species. Lectins are proteins that specifically bind to carbohydrates and, consequently, modulate different biological functions. In this study, the d-glucose/ d-mannose-binding lectins (from seeds of Dioclea megacarpa, D. rostrata and D. violacea and D-galactose-binding lectins (from seeds of Bauhinia variegata, Erythina velutina and Vatairea macrocarpa were purified using chromatographic techniques and evaluated for their effect on the growth of R. tropici CIAT899. All lectins were assayed with a satisfactory degree of purity according to SDS-PAGE analysis, and stimulated bacterial growth; in particular, the Dioclea rostrata lectin was the most active among all tested proteins. As confirmed in the present study, both d-galactose- and d-glucose/d-mannose-binding lectins purified from the seeds of leguminous plants may be powerful biotechnological tools to stimulate the growth of R. tropici CIAT99, thus improving symbiotic interaction between rhizobia and common bean and, hence, the production of this field crop.

  4. Crop-insurance

    NARCIS (Netherlands)

    Wijk, van der S.

    1945-01-01

    Crop insurance was fairly new in the Netherlands but there was no legal objection or limitation to particular crops. If a crop were insured, it was important that the whole area of the crop were insured. Speculative insurance seemed preferable to mutual insurance.

    Crop insurance covered all risks

  5. AgRISTARS: Early warning and crop condition assessment. Plant cover, soil temperature, freeze, water stress, and evapotranspiration conditions

    Science.gov (United States)

    Wiegand, C. L. (Principal Investigator); Nixon, P. R.; Gausman, H. W.; Namken, L. N.; Leamer, R. W.; Richardson, A. J.

    1981-01-01

    Emissive (10.5 to 12.5 microns) and reflective (0.55 to 1.1 microns) data for ten day scenes and infrared data for six night scenes of southern Texas were analyzed for plant cover, soil temperature, freeze, water stress, and evapotranspiration. Heat capacity mapping mission radiometric temperatures were: within 2 C of dewpoint temperatures, significantly correlated with variables important in evapotranspiration, and related to freeze severity and planting depth soil temperatures.

  6. Tenor of macro nutrients and dry matter productivity of covering crops in function of the potassium doses

    Directory of Open Access Journals (Sweden)

    Amilton Ferreira da Silva

    2014-01-01

    Full Text Available With the adoption of the system of direct sowing it is necessary the formation of a straw layer in the surface of the soils. In this sense, some species of grass can be used for that goal, besides; those plants can act in the recycling for the accumulation of nutrients in the aerial part, and its readiness for the subsequent culture. The potassium is one of the most accumulated nutrients for many of those plants. The objective of this work was to quantify the macronutrients tenor and the productivity of dry matter of Penisetum glaucum L. and Panicum miliaceum L. under different potassium doses. A blocks at random design, with the treatments disposed in factorial 3x2, was used, being the factors: covering cultures (P.glaucum and P. miliaceum and potassium doses (0; 50 and 100 kg ha-1 of K2 O, with four repetitions. The matter dries was evaluated and the tenors of N, P, K, Ca, Mg and S in them, at 50 days after sowing covering cultures. P.glaucum produced larger dry matter content and tenor of N, K and Mg in the aerial part, independently of the K dose applied, while the tenor of P decreased with the application of high dose of K in the soil. The application of K influenced on the tenors of Ca and S in the two covering cultures, nevertheless P.glaucum accumulated higher tenor of those macronutrients in the absence of application of K.

  7. Associations between soil bacterial community structure and nutrient cycling functions in long-term organic farm soils following cover crop and organic fertilizer amendment.

    Science.gov (United States)

    Fernandez, Adria L; Sheaffer, Craig C; Wyse, Donald L; Staley, Christopher; Gould, Trevor J; Sadowsky, Michael J

    2016-10-01

    Agricultural management practices can produce changes in soil microbial populations whose functions are crucial to crop production and may be detectable using high-throughput sequencing of bacterial 16S rRNA. To apply sequencing-derived bacterial community structure data to on-farm decision-making will require a better understanding of the complex associations between soil microbial community structure and soil function. Here 16S rRNA sequencing was used to profile soil bacterial communities following application of cover crops and organic fertilizer treatments in certified organic field cropping systems. Amendment treatments were hairy vetch (Vicia villosa), winter rye (Secale cereale), oilseed radish (Raphanus sativus), buckwheat (Fagopyrum esculentum), beef manure, pelleted poultry manure, Sustane(®) 8-2-4, and a no-amendment control. Enzyme activities, net N mineralization, soil respiration, and soil physicochemical properties including nutrient levels, organic matter (OM) and pH were measured. Relationships between these functional and physicochemical parameters and soil bacterial community structure were assessed using multivariate methods including redundancy analysis, discriminant analysis, and Bayesian inference. Several cover crops and fertilizers affected soil functions including N-acetyl-β-d-glucosaminidase and β-glucosidase activity. Effects, however, were not consistent across locations and sampling timepoints. Correlations were observed among functional parameters and relative abundances of individual bacterial families and phyla. Bayesian analysis inferred no directional relationships between functional activities, bacterial families, and physicochemical parameters. Soil functional profiles were more strongly predicted by location than by treatment, and differences were largely explained by soil physicochemical parameters. Composition of soil bacterial communities was predictive of soil functional profiles. Differences in soil function were

  8. Yield and yield structure of spring barley (Hodeum vulgare L. grown in monoculture after different stubble crops

    Directory of Open Access Journals (Sweden)

    Dorota Gawęda

    2012-12-01

    Full Text Available A field experiment was conducted in the period 2006- 2008 in the Uhrusk Experimental Farm belonging to the University of Life Sciences in Lublin. The experimental factor was the type of stubble crop ploughed in each year after harvest of spring barley: white mustard, lacy phacelia, winter rape, and a mixture of narrow-leaf lupin with field pea. In the experiment, successive spring barley crops were grown one after the other (in continuous monoculture. The aim of the experiment was to evaluate the effect of stubble crops used on the size and structure of barley yield. The three-year study showed an increasing trend in grain yield of spring barley grown after the mixture of legumes, lacy phacelia, and white mustard compared to its size in the treatment with no cover crop. Straw yield was significantly higher when barley was grown after the mixture of narrowleaf lupin with field pea than in the other treatments of the experiment. The type of ploughed-in stubble crop did not modify significantly plant height, ear length, and grain weight per ear. Growing the mixture of leguminous plants as a cover crop resulted in a significant increase in the density of ears per unit area in barley by an average of 14.7% relative to the treatment with winter rape. The experiment also showed the beneficial effect of the winter rape cover crop on 1000-grain weight of spring barley compared to that obtained in the treatments with white mustard and the mixture of legumes. All the cover crops caused an increase in the number of grains per ear of barley relative to that found in the control treatment. However, this increase was statistically proven only for the barley crops grown after lacy phacelia and the mixture of legumes.

  9. Modeling soil organic carbon stock after 10 years of cover crops in Mediterranean vineyards: improving ANN prediction by digital terrain analysis.

    Science.gov (United States)

    Lo Papa, Giuseppe; Novara, Agata; Santoro, Antonino; Gristina, Luciano

    2014-05-01

    Estimate changes in soil organic carbon (SOC) stock after Agro Environment Measures adoption are strategically for national and regional scale. Uncertainty in estimates also represents a very important parameter in terms of evaluation of the exact costs and agro environment payments to farmers. In this study we modeled the variation of SOC stock after 10-year cover crop adoption in a vine growing area of South-Eastern Sicily. A paired-site approach was chosen to study the difference in SOC stocks. A total 100 paired sites (i.e. two adjacent plots) were chosen and three soil samples (Ap soil horizons, circa 0-30 cm depth) were collected in each plot to obtain a mean value of organic carbon concentration for each plot. The variation of soil organic carbon (SOCv) for each plot was calculated by differences between concentrations of the plot subjected to cover crops (SOC10) and the relative plot subjected to traditional agronomic practices (SOC0). The feasibility of using artificial neural networks as a method to predict soil organic carbon stock variation and the contribution of digital terrain analysis to improve the prediction were tested. We randomly subdivided the experimental values of SOC-stock difference in 80 learning samples and 20 test samples for model validation. SOCv was strongly correlated to the SOC0 concentration. Model validation using only SOCv as unique covariate showed a training and test perfection of 0.724 and 0.871 respectively. We hypothesized that terrain-driven hydrological flow patterns, mass-movement and local micro-climatic factors could be responsible processes contributing for SOC redistributions, thus affecting soil carbon stock in time. Terrain attributes were derived by digital terrain analysis from the 10 m DEM of the study area. A total of 37 terrain attributes were calculated and submitted to statistical feature selection. The Chi-square ranking indicated only 4 significant covariates among the terrain attributes (slope height

  10. The impact of no-tillage cultivation and white mustard as a cover crop on weed infestation and yield of carrot and red beet

    Directory of Open Access Journals (Sweden)

    Andrzej Borowy

    2015-03-01

    Full Text Available In a two-year field experiment, no-tillage cultivation using white mustard (Sinapis alba L. ‘Bardena’, 30 kg ha−1, as a cover crop did not influence emergence of red beet (Beta vulgaris L. ‘Czerwona Kula REW’ and had a favorable effect on emergence of carrot (Daucus carota L. ‘Berlikumer 2 – Perfekcja REW’. However, further growth of both vegetables was significantly slower under no-tillage cultivation. Both vegetables produced a higher yield of roots and the diameter of these roots was bigger under conventional cultivation. The effect of cultivation method on the content of total nitrogen, phosphorus, potassium, calcium and magnesium in carrot and red beet leaves varied, while the content of dry matter, monosaccharides and total sugars was significantly higher in the roots of both vegetables harvested under no-tillage cultivation. The number of weeds growing on no-tilled plots covered with mustard mulch 4 weeks after seed sowing was lower by about 75%, but their fresh weight was higher more than 6 times in comparison to that under conventional cultivation. This was caused by the emergence of wintering and winter hardy weeds in places not covered by mustard plants in the autumn of the year preceding the cultivation of vegetables. Next year, they started to grow in the early spring and some of them produced a considerable amount of fresh weight and attained the flowering stage in the middle of April.

  11. Ciclagem de nutrientes por plantas de cobertura na entressafra em um solo de cerrado Nutrient cycling in off-season cover crops on a Brazilian savanna soil

    Directory of Open Access Journals (Sweden)

    Carlo Adriano Boer

    2007-09-01

    Full Text Available O objetivo deste trabalho foi avaliar o acúmulo e a liberação de nutrientes (N, P, K, Ca, Mg e S de resíduos culturais de plantas de cobertura na entressafra, em condições de Cerrado. O experimento foi conduzido em um Latossolo Vermelho distroférrico com textura argilosa. As plantas de cobertura avaliadas foram: amaranto (Amaranthus cruentus L., milheto (Pennisetum glaucum L. e capim-pé-de-galinha (Eleusine coracana (L. Gaertn.. O delineamento experimental utilizado foi o de blocos ao acaso, no esquema de parcelas subdivididas, com quatro repetições. Na fase de florescimento das espécies, foi avaliada a produção de matéria seca e o acúmulo de nutrientes. A fim de avaliar a liberação de nutrientes dos resíduos culturais, o material vegetal de cada espécie foi acondicionado em sacolas de náilon, as quais foram dispostas sobre o solo e seu conteúdo analisado em intervalos de 30 dias, até 240 dias após sua instalação. As maiores quantidades de nutrientes acumulados na fitomassa das plantas de cobertura foram observadas no milheto e no capim-pé-de-galinha. O potássio foi o nutriente acumulado em maior quantidade, chegando a atingir 416,9 kg ha-1 no milheto. As maiores taxas de liberação de nutrientes foram observadas nos resíduos culturais do amaranto.The objective of this work was to evaluate the accumulation and the liberation of nutrients (N, P, K, Ca, Mg and S of cultural residues by three species of cover crops, in off-season. Tested cover crops were amaranthus (Amaranthus cruentus L., pearl millet (Pennisetum glaucum L. and finger millet (Eleusine coracana (L. Gaertn.. The experiment was carried out in a Typic Haplorthox clay texture soil. A randomized block desing in a split-plot array in time, with four replications, was used. At the flowering of the species, the production of dry matter and the accumulation of nutrients were evaluated. Proportional samples of dry matter of each cover crop species were placed in

  12. Developmental morphology of cover crop species exhibit contrasting behaviour to changes in soil bulk density, revealed by X-ray computed tomography.

    Science.gov (United States)

    Burr-Hersey, Jasmine E; Mooney, Sacha J; Bengough, A Glyn; Mairhofer, Stefan; Ritz, Karl

    2017-01-01

    Plant roots growing through soil typically encounter considerable structural heterogeneity, and local variations in soil dry bulk density. The way the in situ architecture of root systems of different species respond to such heterogeneity is poorly understood due to challenges in visualising roots growing in soil. The objective of this study was to visualise and quantify the impact of abrupt changes in soil bulk density on the roots of three cover crop species with contrasting inherent root morphologies, viz. tillage radish (Raphanus sativus), vetch (Vicia sativa) and black oat (Avena strigosa). The species were grown in soil columns containing a two-layer compaction treatment featuring a 1.2 g cm-3 (uncompacted) zone overlaying a 1.4 g cm-3 (compacted) zone. Three-dimensional visualisations of the root architecture were generated via X-ray computed tomography, and an automated root-segmentation imaging algorithm. Three classes of behaviour were manifest as a result of roots encountering the compacted interface, directly related to the species. For radish, there was switch from a single tap-root to multiple perpendicular roots which penetrated the compacted zone, whilst for vetch primary roots were diverted more horizontally with limited lateral growth at less acute angles. Black oat roots penetrated the compacted zone with no apparent deviation. Smaller root volume, surface area and lateral growth were consistently observed in the compacted zone in comparison to the uncompacted zone across all species. The rapid transition in soil bulk density had a large effect on root morphology that differed greatly between species, with major implications for how these cover crops will modify and interact with soil structure.

  13. Crescimento e produtividade do meloeiro Torreon influenciado pela cobertura do solo = Growth and yield of the Torreon melon crop influenced by soil cover

    Directory of Open Access Journals (Sweden)

    Elís Regina Costa de Morais

    2010-04-01

    Full Text Available Objetivou-se com este trabalho, avaliar índices de crescimento e fisiológicos do meloeiro em função dos graus-dia acumulados e determinar a relação dos índices fisiológicos com a produtividade da cultura em coberto com filme plástico nas cores preto, prateado, amarelo e marrom, e do solo descoberto como testemunha. O experimento foi desenvolvido na Fazenda Santa Júlia Agrocomercial Exportadora de Frutos Tropicais Ltda., Mossoró, Estado do Rio Grande do Norte (agosto-outubro de 2003, em Latossolo Vermelho eutrófico Argissólico, utilizando-se o melão Torreon em blocos casualizados comquatro repetições. A taxa de crescimento absoluta e a taxa de crescimento relativa para o número de folhas e índice de área foliar foram influenciadas pela cobertura do solo e decresceram com o desenvolvimento da planta, e ainda que a maior produtividade de frutoscomercializáveis foi registrada nas coberturas do solo com plástico.The objective of this work was to evaluate the growth and physiological indexes of the melon crop in function of accumulated degree-days and to determine the relationship between the physiological index and yield of the crop in soil covered with plastic film in the colors black, silver, yellow, and brown, and of the uncovered soil as witness. The experiment was conducted at Fazenda Santa Júlia Agrocomercial Exportadora de Frutos Tropicais Ltda, Mossoró, Rio Grande do Norte State (August-October 2003 in Oxissol, using the Torreon melon in a randomized experimental blocks design with four replications. The relative growth rate for the number of leaves and leaf area index were influenced by soil cover and decreased with the development of the plant; the highestproductivity of marketable fruits was registered on plastic soil coverage.

  14. Developmental morphology of cover crop species exhibit contrasting behaviour to changes in soil bulk density, revealed by X-ray computed tomography.

    Directory of Open Access Journals (Sweden)

    Jasmine E Burr-Hersey

    Full Text Available Plant roots growing through soil typically encounter considerable structural heterogeneity, and local variations in soil dry bulk density. The way the in situ architecture of root systems of different species respond to such heterogeneity is poorly understood due to challenges in visualising roots growing in soil. The objective of this study was to visualise and quantify the impact of abrupt changes in soil bulk density on the roots of three cover crop species with contrasting inherent root morphologies, viz. tillage radish (Raphanus sativus, vetch (Vicia sativa and black oat (Avena strigosa. The species were grown in soil columns containing a two-layer compaction treatment featuring a 1.2 g cm-3 (uncompacted zone overlaying a 1.4 g cm-3 (compacted zone. Three-dimensional visualisations of the root architecture were generated via X-ray computed tomography, and an automated root-segmentation imaging algorithm. Three classes of behaviour were manifest as a result of roots encountering the compacted interface, directly related to the species. For radish, there was switch from a single tap-root to multiple perpendicular roots which penetrated the compacted zone, whilst for vetch primary roots were diverted more horizontally with limited lateral growth at less acute angles. Black oat roots penetrated the compacted zone with no apparent deviation. Smaller root volume, surface area and lateral growth were consistently observed in the compacted zone in comparison to the uncompacted zone across all species. The rapid transition in soil bulk density had a large effect on root morphology that differed greatly between species, with major implications for how these cover crops will modify and interact with soil structure.

  15. Plantas de cobertura, manejo da palhada e produtividade da mamoneira no sistema plantio direto Cover crops, straw mulch management and castor bean yield in no-tillage system

    Directory of Open Access Journals (Sweden)

    Jayme Ferrari Neto

    2011-12-01

    Full Text Available Espécies de cobertura que apresentem elevada produção de fitomassa e reciclagem de nutrientes são essenciais para maximizar a produtividade das culturas em sucessão, no sistema plantio direto. O presente trabalho teve por objetivo avaliar a produção de massa de matéria seca e o acúmulo de nutrientes pelo guandu-anão (Cajanus cajan e o milheto (Pennisetum glaucum, em cultivo solteiro e consorciado, e o efeito do manejo mecânico da palhada na produtividade da mamoneira de safrinha, na fase de implantação do sistema plantio direto. O experimento foi instalado em um Nitossolo Vermelho, em Botucatu, SP. O delineamento foi o de blocos ao acaso, em parcelas subdivididas, com quatro repetições. As parcelas foram constituídas por três coberturas vegetais (guandu-anão, milheto e o cultivo consorciado das duas espécies e as subparcelas pela ausência ou presença do manejo mecânico da palhada com triturador horizontal, 20 dias após o manejo químico. O milheto solteiro produziu maior quantidade de massa de matéria seca (14.040 kg ha-1, apresentou maiores concentrações de K e Mg e acumulou maiores quantidades de macronutrientes na parte aérea. A mamoneira apresentou maior produtividade de grãos em sucessão ao consórcio guandu-anão + milheto. A produtividade de grãos da mamoneira foi maior na ausência do manejo mecânico da palhada.Cover crops that have high phytomass production and nutrient cycling are essential to maximize the crop yields in succession under no-tillage system. This study aimed to evaluate dry matter production and nutrients accumulation by pigeonpea (Cajanus cajan and pearl millet (Pennisetum glaucum, in sole crop and intercropped, and the effect of straw mulch mechanical management on out-of-season castor bean performance, in no-tillage system establishment. The experiment was carried out on a Rhodic Nitisol, in Botucatu, SP, Brazil. A randomized blocks design, in a split-plot scheme, with four replications

  16. Taxonomic studies of nodulated leguminous weeds from the flora of ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-05-18

    May 18, 2009 ... Taxonomic studies of nodulated leguminous weeds from the flora of North Western part (Dera Ismail Khan) of Pakistan. Sarfaraz Khan Marwat*, Mir Ajab Khan, Mushtaq Ahmad, Muhammad Zafar, Farooq Ahmad and Abdul Nazir. Department of Plant Sciences, Quaid-i-Azam University Islamabad, Pakistan.

  17. Antifungal potential of leaf extracts of leguminous trees against ...

    African Journals Online (AJOL)

    In order to search environmental friendly alternatives from natural resources, methanolic extracts of three leguminous tree species namely Acacia nilotica (L.) Willd. ex Delile subsp. indica (Benth.) Brenan, Prosopis juliflora (Sw.) DC. and Albizia lebbeck (L.) Benth. were evaluated for their antifungal activity against S. rolfsii ...

  18. Taxonomic studies of nodulated leguminous weeds from the flora of ...

    African Journals Online (AJOL)

    Taxonomic studies of nodulated leguminous weeds from the flora of North Western part (Dera Ismail Khan) of Pakistan. ... Results were systematically arranged by alphabetic order of botanical names, followed by synonyms (if any), description of the plant, flowering and fruiting period, type, local and general distribution.

  19. Qualitative attributes and postharvest conservation of green ears of maize grown on different cover crops in organic no-till system

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Favarato

    Full Text Available ABSTRACT Postharvest quality of sweet maize varies depending on the type of seed, soil, quality of fertilizer, climatic conditions, and stage of maturation. This study aimed to evaluate the post-harvest quality and shelf life of green ears of maize grown on three soil covers in organic no-till sytem. The study was conducted in the municipality of Domingos Martins, ES (20° 22'16.91" S and 41° 03' 41.83" W. The experiment was arranged in a randomized block design with six replications and five treatments, consisting of three cover crops in organic no-till system: black-oat straw, white lupin, oat/lupin intercrop and two systems, organic and conventional, without straw. Maize double hybrid AG-1051 was sown in a spacing of 1.00 x 0.20 m. The variables evaluated included relative percentage of grain, straw and cob, pH, titratable acidity, soluble solids, grain moisture and shelf life. The use of different straws in the organic no-till system does not influence the postharvest quality of green ears. Ears packed in polystyrene trays with plastic film are suitable for marketing until the fifth day of storage at room temperature.

  20. Soybean growth and yield under cover crops Análise de crescimento e produtividade de grãos de soja sobre plantas de cobertura

    Directory of Open Access Journals (Sweden)

    Priscila de Oliveira

    2013-04-01

    Full Text Available The use of cover crops in no-tillage systems can provide better conditions for the development of soybean plants with positive effects on grain yield and growth analysis techniques allow researchers to characterize and understand the behavior of soybean plants under different straw covers. Thus, the aim of this study was to characterize, using growth analysis, yield components and agronomic performance of soybean under common bean, Brachiaria brizantha and pearl millet straws. The experiment was performed on a soil under cerrado in the municipality of Santo Antônio de Goiás, GO. The experiment was arranged in a randomized complete block design with three treatments (cover crops and five replications. Soybean grain yield was lower in the B. brizantha straw treatment (3,708 kg ha-1 than both in the pearl millet (4.772 kg ha-1 and common bean straw treatments (5,200 kg ha-1. The soybean growth analysis in B. brizantha, pearl millet and common bean allowed characterizing the variation in the production of dry matter of leaves, stems, pods and total and leaf area index that provided different grain yields. The cover crop directly affects the soybean grain yield.O uso de plantas de cobertura no sistema plantio direto pode proporcionar melhores condições para o desenvolvimento da cultura da soja com reflexos positivos na produtividade de grãos, e o uso da técnica de análise de crescimento permitirá caracterizar e entender o comportamento das plantas de soja sobre diferentes palhadas. Dessa forma, o objetivo deste trabalho foi caracterizar, por meio da análise de crescimento, os componentes e o desempenho agronômico da soja sobre as palhadas de feijão-comum, Brachiaria brizantha e milheto. O experimento foi conduzido em solo de cerrado no município de Santo Antônio de Goiás, Estado de Goiás. O delineamento experimental foi o de blocos completos casualizados, com três tratamentos (palhadas de cobertura e cinco repetições. A

  1. Bacterial diversity in the rhizosphere of cucumbers grown in soils covering a wide range of cucumber cropping histories and environmental conditions.

    Science.gov (United States)

    Tian, Yongqiang; Gao, Lihong

    2014-11-01

    Rhizosphere microorganisms in soils are important for plant growth. However, the importance of rhizosphere microorganisms is still underestimated since many microorganisms associated with plant roots cannot be cultured and since the microbial diversity in the rhizosphere can be influenced by several factors, such as the cropping history, biogeography, and agricultural practice. Here, we characterized the rhizosphere bacterial diversity of cucumber plants grown in soils covering a wide range of cucumber cropping histories and environmental conditions by using pyrosequencing of bacterial 16S rRNA genes. We also tested the effects of compost addition and/or bacterial inoculation on the bacterial diversity in the rhizosphere. We identified an average of approximately 8,883 reads per sample, corresponding to around 4,993 molecular operational taxonomic units per sample. The Proteobacteria was the most abundant phylum in almost all soils. The abundances of the phyla Bacteroidetes, Actinobacteria, Firmicutes, Acidobacteria, and Verrucomicrobia varied among the samples, and together with Proteobacteria, these phyla were the six most abundant phyla in almost all analyzed samples. Analyzing all the sample libraries together, the predominant genera found were Flavobacterium, Ohtaekwangia, Opitutus, Gp6, Steroidobacter, and Acidovorax. Overall, compost and microbial amendments increased shoot biomass when compared to untreated soils. However, compost addition decreased the bacterial α-diversity in most soils (but for three soils compost increased diversity), and no statistical effect of microbial amendment on the bacterial α-diversity was found. Moreover, soil amendments did not significantly influence the bacterial β-diversity. Soil organic content appeared more important than compost and microbial amendments in shaping the structure of bacterial communities in the rhizosphere of cucumber.

  2. CHEMICAL ATTRIBUTES OF A SOIL CULTIVATED WITH DIFFERENT COVER CROPS ATRIBUTOS QUÍMICOS DE SOLO CULTIVADO COM DIFERENTES CULTURAS DE COBERTURA

    Directory of Open Access Journals (Sweden)

    Luís Fernando Stone

    2010-08-01

    Full Text Available  

    The effect of cover crops annually implanted in the summer, since 2001, under no-tillage system, on the soil chemical attributes was evaluated. The experiment was carried out in Embrapa Rice & Beans, in Santo Antônio de Goiás, GO, Brazil, in a Dystrophic Red Latosol (Red Oxisol. Brachiaria brizantha, corn (Zea mays L. associated with B. brizantha, pigeon pea, millet, Panicum maximum, sorghum, Stylosanthes guianensis, and sunn hemp were used as cover crops. Sixty days after the cut of the cover crops, common bean crop was implanted, under a central pivot sprinkler irrigation system. In November 2001, 2005, and 2006, soil samples were collected in the depths of 0-5 cm, 5-10 cm, and 10-20 cm. Immediately after the 2005 sampling, it was applied 4,000 kg ha-1 of dolomitic lime, in all the experimental area. Cover crops affected soil pH and magnesium content in the superficial layer. Soil under millet showed higher phosphorus content in subsuperficial layers, in relation to the initial values. The soil P and Cu contents were higher in the subsuperficial layers, while the other chemical attributes were higher in the superficial layer. There was movement of Ca and Mg in the soil profile, one year after the application of lime in the soil surface.

  3. Macrofauna invertebrada edáfica em cultivo de mandioca sob sistemas de cobertura do solo Edaphic invertebrate macrofauna in cassava cultivation under vegetable cover crops

    Directory of Open Access Journals (Sweden)

    Rogério Ferreira da Silva

    2007-06-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito do cultivo da mandioca em diferentes sistemas de cobertura do solo na densidade e diversidade da comunidade da macrofauna de invertebrados edáfica. O trabalho foi conduzido no Município de Glória de Dourados, MS, num Argissolo Vermelho, sob sistema convencional (SC, plantio direto sobre palhada de mucuna (PDMu, sorgo (PDSo e milheto (PDMi, além de sistema com vegetação nativa (VN, como referencial para comparação. As avaliações foram realizadas em quatro épocas distintas: abril/2003 (antes do plantio, novembro/2003 (6 meses após o plantio, abril/2004 (11 meses após o plantio e novembro/2004 (18 meses após o plantio. Houve efeito da interação entre os sistemas avaliados e as épocas de amostragens sobre a densidade, riqueza e diversidade da macrofauna invertebrada do solo. Entre os grupos da macrofauna invertebrada do solo, cupins, formigas e coleópteros (imaturo e adulto foram predominantes no ambiente estudado. O uso de plantas de cobertura no pré-cultivo de mandioca no sistema plantio direto proporcionou condições para a recomposição da comunidade de macrofauna invertebrada do solo, o que indica que as espécies utilizadas, mucuna, sorgo e milheto, representam alternativas promissoras para melhor manejo dessa cultura.The objective of this work was to evaluate the effect of cassava cultivation under different vegetable cover crops according to the density and diversity of soil invertebrate macrofauna. Field experiment was carried out at Glória de Dourados, Mato Grosso do Sul State, Brazil, on an Oxisol, under conventional drilling (SC, no-tillage system under Stizolobium cinereum (PDMu, Sorghum bicolor (PDSo and Pennisetum glaucum (PDMi mulching, with comparison of native vegetation system (VN. Evaluations were performed in April/2003 (before sowing, November/2003 (6 months after sowing, April/2004 (11 months after sowing and November/2004 (18 months after sowing. Significant

  4. Cover Crops in West Africa

    International Development Research Centre (IDRC) Digital Library (Canada)

    Effects of UV-B on activities of enzymes of secondary phenolic metabolism in barley primary leaves. Physiologia Plantarum, 93, 734–739. Lubis, I.S.; Sastrapradha, S.H.A. 1981. L-dihydroxy-phenylalanine (L-Dopa) in Mucuna seeds. Annales Bogorienses, 7(3), 107–114. Manyam, B. 1995. An alternative medicine treatment ...

  5. Production of pulse in mono-cropped rice system in the coastal region of Eastern India

    International Nuclear Information System (INIS)

    Khan, A.R.; Nanda, P.; Chandra, Dinesh; Ghorai, A.K.; Behera, M.S.

    2001-04-01

    This experiment was undertaken with an objective to increase the yield of black-gram leguminous pulse crop through optimal doses of phosphatic fertilizer with supplemental irrigation in mono-cropped rice-fallow regions of India. Irrigation and phosphorus fertilizer application were introduced for enhancing productivity of black-gram to provide better returns to available water resources

  6. 60 changes in soil properties under alley cropping system of three ...

    African Journals Online (AJOL)

    OLUWOLE AKINNAGBE

    2009-01-01

    Jan 1, 2009 ... A study to evaluate the changes in soil properties, under existing alley cropping system with three leguminous crops (Leucaena ... This exploits the biological .... chemical properties were observed in the last two years of study (2004-2005) over the pre-planting soil result. The pH values in the C. cajan alley.

  7. New Ravenelia species on leguminous hosts from the Brazilian Cerrado

    OpenAIRE

    REZENDE, DENISE V.; DIANESE, JOSÉ C.

    2001-01-01

    Four new Ravenelia species were described on native leguminous hosts from the Brazilian Cerrado, as follows: Ravenelia cerradensis sp. nov., R. chapadensis sp. nov., R. mineirosensis sp. nov. and R. emaensis sp. nov. on Chamaecrista clausenii var. cyclophylla, Chamaecriista conferta var. virgata, Anadenanthera colubrina var. colubrina, and on Anadenanthera sp., respectively. Quatro espécies novas de Ravenelia foram descritas em leguminosas do Cerrado brasileiro, a saber: Ravenelia cerraden...

  8. Protection against productivity versus erosion vineyards. Testing of vegetal covers in slope crops; Proteccion contra la erosion versus productividad en venidos. Ensayos de cubiertas vegetales en cultivos en pendiente

    Energy Technology Data Exchange (ETDEWEB)

    Marques, M. J.; Ruiz-Colmenero, M.; Garcia-Munoz, S.; Cabello, F.; Munoz-Organero, G.; Perez-Jimenez, M. A.; Bienes, R.

    2009-07-01

    Temporary and permanent cover crops were used in three rain fed vineyards in the Center of Spain. They were sown in the middle of the strips to assess their ability to control erosion as well as their influence on grape production. Data from the year 2008 are compared with those obtained with traditional tillage treatment. The permanent cover formed by Brachypodium distachyon showed better ability to control erosion but it produced a decrease in production in young vines. barley and rye treatments were temporary covers, mowed in spring. They also reduced the erosion compared with the tillage however they did not appear to affect the vineyard production. (Author)

  9. Adubação nitrogenada no feijoeiro cultivado sob plantio direto em sucessão de culturas Nitrogen fertilization of common bean grown under no-tillage system after several cover crops

    Directory of Open Access Journals (Sweden)

    Pedro Marques da Silveira

    2005-04-01

    Full Text Available O nitrogênio é um nutriente essencial ao feijoeiro e sua carência é observada em quase todos os solos. O objetivo deste trabalho foi avaliar a resposta do feijoeiro irrigado por aspersão à adubação nitrogenada em cobertura, num Latossolo Vermelho distrófico. O cultivo foi realizado em sistema pivô central, em condições de plantio direto com sucessão de diferentes culturas. Os tratamentos constituíram-se de sete culturas: braquiária cv. Marandu, milho em consórcio com braquiária, guandu, milheto, mombaça, sorgo granífero e estilosantes cv. Mineirão. Sobre as palhadas picadas das culturas, foi semeado o feijão cv. Pérola e aplicados em cobertura 0, 30, 60 e 120 kg ha-1 de N (uréia. Houve efeito das palhadas sobre a produtividade de grãos e as maiores produtividades alcançadas foram sobre as palhadas de milheto e do guandu. O feijoeiro responde à aplicação de N em cobertura em todas as sucessões, com resposta quadrática sobre o milheto e o guandu, e linear nas demais.Nitrogen is an essential nutrient to common bean and its shortage is observed in almost all types of soils. The objective of this work was to evaluate the performance of irrigated common bean grown under no-tillage in succession to different cover crops and in relation to nitrogen topdressing fertilization in a Dystrophic Red Latosol (Typic Hapludox. The treatments were seven cover crops: Brachiaria brizantha cv. Marandu, B. brizantha associated with corn (Zea mays L., pigeon pea (Cajanus cajan L. Millisp, millet (Pennisetum glaucum L. R. Br., Panicum maximum cv. Mombaça, sorghum (Sorghum bicolor L. Moench and Stylosanthes guianensis cv. Mineirão. The bean crop (cv. Perola was seeded on the cover crop and 0, 30, 60, and 120 kg ha-1 of N (urea were topdressed. The cover crops affected the common bean grain yield. The highest grain yields were attained on millet and pigeon pea mulches. The common bean grain yield showed response to nitrogen topdressing

  10. Diferentes manejos da cobertura vegetal de aveia preta em pomar no sul do Brasil Different management of black oat crop cover in orchard at Southern Brazil

    Directory of Open Access Journals (Sweden)

    Andrea De Rossi

    2007-01-01

    Full Text Available O experimento foi implantado no Pomar Didático do Centro Agropecuário da Palma, da Faculdade de Agronomia Eliseu Maciel, Universidade Federal de Pelotas, com o objetivo de avaliar o efeito de diferentes manejos da cobertura vegetal de aveia preta sobre a porcentagem de água, temperatura, conteúdo de matéria orgânica e resistência à penetração do solo e ao grau de infestação de plantas daninhas em pomar. Os tratamentos constaram de diferentes técnicas de manejo da cobertura vegetal de solo com aveia preta: incorporação da aveia ao solo; dessecação com herbicida; acamamento com rolo faca; roçada a 5 cm e uma testemunha (solo descoberto. A semeadura da aveia foi realizada em abril de 2002 e a aplicação dos tratamentos, no fim do mês de agosto do mesmo ano. O experimento foi desenvolvido em blocos casualizados, com três blocos, cinco tratamentos e uma repetição. Os dados foram submetidos à analise da variância através do teste F e as médias comparadas pelo teste de Duncan. Nos tratamentos em que houve manutenção da cobertura vegetal no pomar, observaram-se redução da temperatura, aumento da umidade do solo e da resistência à penetração. O revolvimento do solo aumentou a diversidade de plantas daninhas. A incorporação da aveia preta, após 60 dias, teve o mesmo comportamento que o solo descoberto, quanto à umidade e temperatura do solo.The experiment was managed in the Didactic Orchard of the Agricultural Center of Palma, which belongs to the Federal University of Pelotas (UFPel. The treatments consisted of 5 different managements of black oat crop cover: incorporation of black oat to soil; chemical management with herbicide; lodging; mowing at 5 cm and control (uncovered soil. The sowing of the oat was accomplished by April of 2002 and the installation of the experiment, by the end of August of the same year. The analyzed variables were percentage of soil moisture at a depth of 15 cm, temperature of the soil at

  11. [Definition of saponins in new sorts of pea and haricot flour their influence on foaming property of leguminous cultures].

    Science.gov (United States)

    Artemova, E N; Sychev, S N; Tsareva, N I

    2008-01-01

    Foam-forming properties of the leguminous cultures are directly associated with their chemical composition and first of all with the present of proteins and saponins. Basic results and parametrs of chromatographic analysis of the leguminous cultures are provided.

  12. Cover crops growth under water deficitCrescimento de plantas de cobertura sob déficit hídrico

    Directory of Open Access Journals (Sweden)

    Edison Ulisses Ramos Junior

    2013-03-01

    Full Text Available One of the challenges to be overcome in no till deploying in tropical regions is the production of straw in the offseason, a period commonly with low water availability. To help in the choice of species to be used as cover crop in dry winter regions, the aim of this work was to evaluate the effect of soil water potential on growth of black oat (Avena strigosa Sckreb, pearl millet (Pennisetum glaucum (L. R. Brown, grain sorghum (Sorghum bicolor L. Moench. e guinea sorghum (Sorghum bicolor subespécie bicolor raça guinea. Pearl millet is a good option to be cropped during offseason by show high yield potencial, even been more sensitive to water deficit. Grain sorghum and guinea sorghum are also good options, particularly by showed abundant root system, which possibly gives them a certain tolerance to low water availability conditions. The black oat, even with high tolerance to water stress (tolerance conferred by highest percentage of fine roots, seems to be much affected by higher temperatures, common to these regions. Um dos desafios a serem vencidos na implantação do sistema de semeadura direta em regiões tropicais é a produção de palhada na entressafra, período comumente com baixa disponibilidade hídrica. Visando auxiliar a escolha das espéciesa serem empregadas como planta de cobertura em regiões de inverno seco, objetivou-se com este trabalho avaliar o efeito de potenciais de água no solo no crescimento de aveia preta (Avena strigosa Sckreb, milheto (Pennisetum glaucum (L. R. Brown, sorgogranífero (Sorghum bicolor L. Moench. esorgo-de-guiné(Sorghum bicolor subespécie bicolor raça guinea, bem como detectar possíveis estratégias destas espécies para contornarem condições de baixa disponibilidade hídrica. O milheto, mesmo sendo mais sensível ao déficit hídrico, é uma boa opção a ser cultivado na entressafra pelo seu elevado potencial produtivo. O sorgo granífero e o sorgo-de-guiné também são boas opções, em

  13. Atributos químicos e estabilidade de agregados sob diferentes culturas de cobertura em Latossolo do cerrado Chemical properties and aggregate stability under different cover crops in cerrado Oxisol

    Directory of Open Access Journals (Sweden)

    Glenio G. Santos

    2012-11-01

    Full Text Available Objetivou-se, com este trabalho, avaliar o efeito de diferentes culturas de cobertura sobre os atributos químicos e a estabilidade de agregados de um Latossolo do cerrado, sob plantio direto. O estudo foi conduzido em área experimental na Embrapa Arroz e Feijão, em Santo Antônio de Goiás, GO. As culturas de cobertura avaliadas foram: braquiária, milho em consórcio com braquiária (integração lavoura-pecuária, guandu anão, milheto, capim mombaça, sorgo granífero, estilosantes e crotalária. As amostras foram coletadas em abril de 2005 e 2006. O delineamento experimental foi o de blocos completos ao acaso com quatro repetições e os tratamentos arranjados em esquema fatorial 8 x 2, sendo oito culturas de cobertura e duas profundidades de amostragem do solo: 0-0,10 e 0,10-0,20 m. As culturas de cobertura influenciam, de forma diferenciada, os valores de pH e os teores de cálcio, magnésio, alumínio, fósforo, potássio, cobre, zinco e ferro do solo. O tratamento estilosantes tem maior poder em acidificar o solo. A agregação do solo varia com as culturas de cobertura e com a profundidade.The objective of this study was to evaluate the effect of different cover crops on chemical properties and aggregate stability in a cerrado Oxisol under no-tillage. The study was carried out in Embrapa Rice and Beans, in Santo Antônio de Goiás, GO, Brazil. The cover crops evaluated were: Urochloa brizantha, Urochloa brizantha and corn in association (crop-livestock integrated, Cajanus cajan, Pennisetum glaucum, Panicum maximum, Sorghum bicolor, Stylosanthes guianensis and Crotalaria juncea. The soil samples were collected in April and September 2005 and April 2006. The experimental design was in completely randomized blocks with four replications and treatments arranged in factorial scheme 8 x 2, eight cover crops and two soil sampling depths, 0-0.10 and 0.10-0.20 m. The different cover crops affect pH values and calcium, magnesium, aluminum

  14. Assessing the impacts of future climate conditions on the effectiveness of winter cover crops in reducing nitrate loads into the Chesapeake Bay Watershed using SWAT model

    Science.gov (United States)

    Lee, Sangchul; Sadeghi, Ali M.; Yeo, In-Young; McCarty, Gregory W.; Hively, W. Dean

    2017-01-01

    Winter cover crops (WCCs) have been widely implemented in the Coastal Plain of the Chesapeake Bay watershed (CBW) due to their high effectiveness at reducing nitrate loads. However, future climate conditions (FCCs) are expected to exacerbate water quality degradation in the CBW by increasing nitrate loads from agriculture. Accordingly, the question remains whether WCCs are sufficient to mitigate increased nutrient loads caused by FCCs. In this study, we assessed the impacts of FCCs on WCC nitrate reduction efficiency on the Coastal Plain of the CBW using Soil and Water Assessment Tool (SWAT) model. Three FCC scenarios (2085 – 2098) were prepared using General Circulation Models (GCMs), considering three Intergovernmnental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) greenhouse gas emission scenarios. We also developed six representative WCC implementation scenarios based on the most commonly used planting dates and species of WCCs in this region. Simulation results showed that WCC biomass increased by ~ 58 % under FCC scenarios, due to climate conditions conducive to the WCC growth. Prior to implementing WCCs, annual nitrate loads increased by ~ 43 % under FCC scenarios compared to the baseline scenario (2001 – 2014). When WCCs were planted, annual nitrate loads were substantially reduced by ~ 48 % and WCC nitrate reduction efficiency water ~ 5 % higher under FCC scenarios relative to the baseline. The increase rate of WCC nitrate reduction efficiency varied by FCC scenarios and WCC planting methods. As CO2 concentration was higher and winters were warmer under FCC scenarios, WCCs had greater biomass and therefore showed higher nitrate reduction efficiency. In response to FCC scenarios, the performance of less effective WCC practices (e.g., barley, wheat, and late planting) under the baseline indicated ~ 14 % higher increase rate of nitrate reduction efficiency compared to ones with better effectiveness under the baseline (e

  15. Emergency and growth of cover crops in function of the sowing depth / Emergência e crescimento de plantas de cobertura em função da profundidade de semeadura

    Directory of Open Access Journals (Sweden)

    Fabiano André Petter

    2009-07-01

    Full Text Available The objective of this study was evaluated emergence of four cover crops at different seeding depths, in order to use them intercropped and oversown with annual crops. The experiment was installed in a greenhouse, and it was organized as a 5 × 7 factorial combination, with crop of fve cover crops: Pennisetum glaucum var. ADR 300, ADR 500, and BN2, Eleusine coracana (fnger millet, and a cober crop( hybrid sorghum with sudan-grass [Sorghum bicolor x Sorghum sudanese]; seven cover crops seeding depths: (0 cm without any mulch; 0 cm with a mulch of leaves over the seeds;1; 4; 8; 10; and 15 cm.The cover crops were cropping in vases for 40 days. It was evaluated emergence index, emergence time, plant height, green biomass and dry biomass of the above-ground part, leaf area, root dry biomass and root length density. There was reduction of emergence when cover crops was seeded at zero cm depth with a mulch of leaves, except for the E. coracana, that had a better performance in the oversown. Pearl millets and hybrid S. bicolor x S. sudanense show up some restrictions when used in simultaneous consortium. The 15 cm sowing depth must not be used.O objetivo do trabalho foi avaliar a emergência de cinco plantas de cobertura em diferentes profundidades de semeadura, visando à obtenção de informações que subsidiem sua utilização na consorciação e sobressemeadura de culturas anuais. O experimento foi conduzido em casa-de-vegetação, no delineamento experimental de blocos ao acaso, em esquema fatorial 5 x 7, composto pelas plantas de cobertura Pennisetum glaucum var. ADR 300, ADR 500 e BN2, Eleusine coracana e cober crop [híbrido de sorgo com capim-sudão (Sorghum bicolor x Sorghum sudanense], e por sete profundidades de semeadura das plantas de cobertura (0 cm sem presença de folhas de soja sobre as sementes, 0 com presença de folhas de soja sobre as sementes, 1, 4, 8, 10 e 15 cm. As sementes foram semeadas em vasos e as plantas cultivadas por 40

  16. Desempenho operacional de semeadura-adubadora em diferentes manejos da cobertura e da velocidade Operational performance of seeder in different forward speed and winter cover crop management

    Directory of Open Access Journals (Sweden)

    Carlos E. A. Furlani

    2007-08-01

    Full Text Available O presente trabalho teve como objetivo avaliar o desempenho de uma semeadora-adubadora no sistema plantio direto. Os fatores estudados foram três manejos das culturas de cobertura, selecionados em função do tamanho de fragmentos da vegetação, triturador de palhas (palha totalmente triturada, roçadora (palha parcialmente picada e rolo-facas (palha acamada, combinados com três velocidades do conjunto trator-semeadora-adubadora, sendo 4,0; 5,0 e 6,0 km h-1. O delineamento experimental foi em blocos casualizados, em esquema fatorial 3 x 3, com nove tratamentos e oito repetições, totalizando 72 observações. Para comparar os tratamentos, avaliaram-se a capacidade de campo operacional, a força de tração e a potência na barra, o consumo horário e por área, e a patinagem dos rodados do trator. O desempenho da semeadora-adubadora não foi influenciado pelos três manejos na cultura de cobertura vegetal. O aumento da velocidade provocou diminuição da força de tração, sendo o inverso para a capacidade de campo operacional e a potência na barra. O consumo horário de combustível aumentou com a velocidade, enquanto o operacional diminuiu.The present work aimed to evaluate the seeder performance in the direct sowing system. The studied factors were three cover crop managements, chosen according to the size of the vegetation fragment, such as straw (straw totally triturated, weeder (straw partially chopped and knife-rolls (straw practically entire, combined with three speeds of the seeder, being 4.0; 5.0 and 6.0 km h-1. The experimental outlining was carried out in casual blocks in factorial scheme 3 x 3, with nine treatments and eight repetitions, totalizing 72 observations. In the course of the experiment the following variants were evaluated: effective field capacity, force and power in the bar, hourly and area consumption of fuel and tractor’s pulleys sliding. The data reached were tabulated and submitted to factorial variant

  17. Bradyrhizobium Populations Occur in Deep Soil under the Leguminous Tree Acacia albida

    Science.gov (United States)

    Dupuy, Nicolas C.; Dreyfus, Bernard L.

    1992-01-01

    Soil cores were drilled under the leguminous tree Acacia albida growing in two different ecoclimatic zones of West Africa: the Sahelian area (100 to 500 mm of annual rainfall) and the Sudano-Guinean area (1,000 to 1,500 mm of annual rainfall). Soil samples were collected at different depths from the surface down to the water table level and analyzed for the presence of rhizobia able to nodulate A. albida. In both areas, population densities of rhizobia were substantially greater near the water table than near the surface. In the Sahelian area, rhizobia were present as deep as 34 m at a concentration of 1.3 × 103/g of soil. In the Sudano-Guinean area, population densities at 0.5 to 4.5 m depth were higher than in the Sahelian area and, at several depths, comparable to that of temperate soils supporting legume crops (104 rhizobia per g of soil). Surface and deep soil isolates from all four sites were found to be slow-growing rhizobia (Bradyrhizobium sp.). The proportion of effective isolates was almost the same within surface and deep soils. PMID:16348745

  18. The effect of cover crop and crop rotation on soil water storage and on sorghum yield Efeito de cultura de cobertura e de rotação de cultura no armazenamento de água do solo e no rendimento de sorgo

    Directory of Open Access Journals (Sweden)

    Demóstenes Marcos Pedrosa de Azevedo

    1999-03-01

    Full Text Available Crop rotation and cover crop can be important means for enhancing crop yield in rainfed areas such as the lower Coastal Bend Region of Texas, USA. A trial was conducted in 1995 as part of a long-term cropping experiment (7 years to investigate the effect of oat (Avena sativa L. cover and rotation on soil water storage and yield of sorghum (Sorghum bicolor L.. The trial design was a RCB in a split-plot arrangement with four replicates. Rotation sequences were the main plots and oat cover crop the subplots. Cover crop reduced sorghum grain yield. This effect was attributed to a reduced concentration of available soil N and less soil water storage under this treatment. By delaying cover termination, the residue with a high C/N acted as an N sink through competition and/or immobilization instead of an N source to sorghum plants. Crop rotation had a significantly positive effect on sorghum yield and this effect was attributed to a significantly larger amount of N concentration under these rotation sequences.Rotação de cultura e cultura de cobertura constituem importantes meios para melhoria do rendimento de culturas em áreas de sequeiro como a região "Coastal Bend" do Estado do Texas. Um ensaio foi conduzido em 1995, como parte de um experimento de longa duração (7 anos, com o objetivo de investigar o efeito da aveia (Avena sativa L. como cultura de cobertura, e da rotação de cultura, no armazenamento da água do solo e no rendimento do sorgo (Sorghum bicolor L.. O delineamento experimental adotado foi o de blocos ao acaso, em parcelas subdivididas, com quatro repetições. As rotações foram alocadas nas parcelas, e a cultura de cobertura, nas subparcelas. A cultura de cobertura reduziu o rendimento do sorgo. Este efeito foi atribuído à reduzida concentração de N disponível do solo. Por atraso no extermínio e incorporação da aveia, seu resíduo, com elevada relação C/N, atuou como dreno, pela imobilização, em lugar de ser fonte

  19. Sistema radicular de plantas de cobertura sob compactação do solo Root system of cover crops under soil compaction

    Directory of Open Access Journals (Sweden)

    Wainer G. Gonçalves

    2006-04-01

    Full Text Available Com o objetivo de avaliar a capacidade de crescimento de raízes em camadas de solo compactadas, quatro espécies de plantas de cobertura (amaranto, milheto ADR 500, capim pé-de-galinha e kenaf foram cultivadas em anéis de PVC, com níveis de compactação em subsuperfície (densidade do solo: 1,18; 1,34; 1,51 e 1,60 Mg m-3, sendo o experimento conduzido em casa de vegetação, utilizando-se de um Latossolo Vermelho distroférrico. A camada compactada em subsuperfície foi restritiva ao crescimento de raízes das espécies estudadas, ocasionando a concentração de raízes na camada superficial. O milheto ADR 500 e o amaranto foram as espécies que se destacaram na produção de massa seca da parte aérea e conseguiram desenvolver-se nas camadas compactadas e abaixo delas. O milheto ADR500 apresentou maior densidade de comprimento radicular em todas as camadas. O capim pé-de-galinha e o amaranto tiveram comportamento semelhante quanto à densidade de comprimento radicular. O capim pé-de-galinha e o kenaf apresentaram menor massa seca de raízes em relação às demais espécies. O kenaf apresentou menores valores de massa seca da parte aérea, mas não foi afetado pela presença de camadas compactadas.With the objective of evaluate the root growth capacity in the compacted soil layer, four vegetal species of the cover crops (amaranth, pearl millet ADR500, finger millet and kenaf were cultivated in columns of PVC with increasing levels of subsurface compaction (soil bulk densities: 1.18; 1.34; 1.51 and 1.60 Mg m-3. The experiment was carried out in a greenhouse conditions, using a Dusky Red Latosol. The subsurface compacted layer was restrictive to the roots growth of the studied species, causing the root concentrating to the surface. Pearl millet ADR500 and the amaranth were the species that had detached in the production of dry matter weight and developed itself in the compacted layers and below of them. Pearl of millet ADR500 presented the

  20. Atributos físicos do solo e produtividade de milho em resposta a culturas de pré-safra Soil physical attributes and corn yield as a response to cover crops prior to corn

    Directory of Open Access Journals (Sweden)

    Eurico Lucas de Sousa Neto

    2008-02-01

    Full Text Available O objetivo deste trabalho foi avaliar os atributos físicos de um Latossolo Vermelho distrófico argiloso e a produtividade de milho em sistemas de manejo que incluem plantas de cobertura cultivadas em pré-safra (setembro a novembro. Foram utilizadas, durante quatro anos, as seguintes plantas de cobertura: crotalária (Crotalaria juncea; milheto (Pennisetum americanum sin. tiphoydes; lab-lab (Dolichus lablab em sistema de semeadura direta; e pousio cultivado em sistema de preparo convencional, antecedendo o cultivo de milho. O delineamento experimental foi de blocos ao acaso com parcelas subdivididas e quatro repetições. Amostras de solo indeformadas foram coletadas para determinações físicas e avaliou-se a produtividade de milho em área de 22,5 m². As plantas de cobertura no sistema de semeadura direta promoveram maior estabilidade de agregados e maior densidade do solo na camada superficial, sem alteração do conteúdo de água disponível às plantas. A utilização de lab-lab, em pré-safra, promoveu a menor produtividade de milho. A utilização de plantas de cobertura em pré-safra no sistema de semeadura direta de milho é viável no Estado de São Paulo.The objective of this work was to evaluate soil physical attributes and corn productivity of a Typic Hapludox in system including cover crops before corn. During four years the following cover crop species were used: sunn hemp (Crotalaria juncea; millet (Pennisetum americanum sin. tiphoydes; lab-lab (Dolichus lablab in no-tillage system. An additional treatment was used with a tillage system composed of a disk plow and two harrowing. The experiment was set up in randomized block with split-plot design, with four repetitions. Undisturbed soil samples were collected for physical determinations and corn yield was evaluated in 22.5 m² areas. The cover crop treatments in no-tillage promoted bigger aggregate stability and bulk density in the superficial layer, but did not affect the

  1. 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...

  2. Efeito de coberturas de inverno e sua época de manejo sobre a infestação de plantas daninhas na cultura de milho Effect of winter cover crops and their management timing on weed infestation in maize crop

    Directory of Open Access Journals (Sweden)

    A.A. Balbinot Jr.

    2007-09-01

    Full Text Available No sistema de plantio direto, a presença de palha sobre o solo proporciona significativa supressão de plantas daninhas. O objetivo deste trabalho foi avaliar o potencial de coberturas de inverno e sua época de manejo em reduzir a infestação de plantas daninhas na cultura de milho quando semeada em sucessão. Dois experimentos foram realizados em Canoinhas, SC, nas safras 2003/04 e 2004/05. No primeiro experimento, avaliaram-se seis coberturas de solo no inverno: nabo forrageiro, aveia-preta, centeio, azevém, consórcio entre aveia-preta e ervilhaca e o consórcio entre nabo forrageiro, aveia-preta, centeio, azevém e ervilhaca. Essas coberturas foram roçadas em três épocas antes da semeadura do milho: 1, 10 e 25 dias. Já no segundo experimento, foram avaliados os efeitos de supressão de plantas daninhas pela palha das seis coberturas citadas anteriormente, mais a ervilhaca. As palhas de azevém e do consórcio das cinco espécies utilizadas no experimento apresentaram alta capacidade em suprimir a emergência e o acúmulo de massa seca das plantas daninhas, enquanto a palha de nabo forrageiro apresentou baixo potencial de supressão. O manejo das coberturas próximo à semeadura da cultura de milho reduziu a infestação de plantas daninhas.Straw on the soil significantly reduces weed infestation under the no-tillage system. The aim of this research was to evaluate the potential of winter cover crops and their management timing in reducing weed infestation in maize crop. Two experiments were carried out in Canoinhas, SC, Brazil, in 2003/2004 and 2004/2005. In the first experiment, six winter cover crops were investigated: oilseed radish, black oat, rye, rye grass, intercropped among black oat and common vetch and among oilseed radish, black oat, rye, ryegrass and common vetch. These cover crops were slashed down at three different times before maize seeding (1, 10 and 25 days. In the second experiment, the potential to reduce weed

  3. Stimulation treatments of large-seed leguminous plants Pt. 1

    International Nuclear Information System (INIS)

    Nagy, Istvan; Borbely, Ferenc; Nagy, Janos; Dezsi, Zoltan

    1983-01-01

    The effect of low dose X-ray irradiation on the sprouting and initial growth of some leguminous plants was studied. After having the seeds of peas, beans, lupines and horse beans irradiated, the sprouting rate, the amount of sprouting plants, the length of the roots, the sprouts and the sprouting plants, the electrolyte conductivity and the water uptake were determined. The height and the amount of the plants were measured after a period of 6 weeks. According to the sprout-length values, an increased variation in the plant features can be observed as a result of irradiation treatment: both stimulation and inhibition of plant growth occured, depending on the variety of the leguminosae. The indices of sprouting and initial growth agree well with each other. (V.N.)

  4. The Current State and Future Directions of Organic No-Till Farming with Cover Crops in Canada, with Case Study Support

    OpenAIRE

    Heather M. Beach; Ken W. Laing; Morris Van De Walle; Ralph C. Martin

    2018-01-01

    Eliminating regular tillage practices in agriculture has numerous ecological benefits that correspond to the intentions of organic agriculture; yet, more tillage is conducted in organic agriculture than in conventional agriculture. Organic systems face more management challenges to avoid tillage. This paper identifies factors to consider when implementing no-till practices particularly in organic agronomic and vegetable crop agriculture and describes techniques to address these factors. In so...

  5. ORGANOFINERY: FROM GREEN CROPS TO PROTEINS, ENERGY AND FERTILISER

    DEFF Research Database (Denmark)

    Salces, Beatriz Molinuevo; Fernandez, Maria Santamaria; Kiel, P.

    Difficulties with the supply of organic protein feed; low crop yields and low value of leguminous forage crops and a lack of organic fertilisers are nowadays some of the major challenges faced in organic farming with monogastric animals. Thus, organic farmers are forced to import feed and manure ...... from conventional farms. In order to overcome these challenges, the OrganoFinery project targets to develop a green biorefinery concept where organic crops are utilised for animal feed, fertiliser and energy production by producing biogas....

  6. Efeito da cobertura vegetal sobre a pérola-da-terra (Hemiptera: Margarodidae na cultura da videira = Effect of cover crops on brazilian ground pearl (Hemiptera: Margarodidae in vineyards

    Directory of Open Access Journals (Sweden)

    Marcos Botton

    2010-10-01

    Full Text Available O uso da cobertura vegetal em vinhedos é uma prática empregada paraminimizar a erosão e melhorar as qualidades químicas e físicas do solo. Neste trabalho, foi avaliado o efeito de coberturas vegetais sobre a população da pérola-da-terra Eurhizococcus brasiliensis (Hemiptera: Margarodidae na cultura da videira. No primeiro experimento, o vinhedo foi mantido sem cobertura vegetal por meio da aplicação trimestral do herbicida glifosato comparado com o uso de vegetação espontânea, durante o ano, de vegetação espontânea, no verão, e de aveia preta no inverno. No segundo experimento foi avaliado o efeito da mucuna-preta (Stizolobium aterrimum cultivada no vinhedo durante o verão comparado com a vegetação espontânea. No primeiro experimento, a população da pérolada-terra nas raízes de plantas de videira foi maior em áreas mantidas sem cobertura vegetal emostrou-se semelhante em áreas onde se manteve a vegetação espontânea, ao longo do ano, e com aveia preta no inverno e vegetação espontânea no verão. A infestação das plantas de videira em áreas onde foi empregada a mucuna-preta durante o verão foi equivalente à da vegetação espontânea. S. aterrimum foi registrada pela primeira vez como hospedeira de E. brasiliensis. The use of cover crops is an important strategy to reduce erosion and improve chemical and physical soil properties. In this work, we evaluate the effect of cover crops to reduce Brazilian ground pearl Eurhizococcus brasiliensis (Hemiptera: Margarodidae infestation in vineyards. In the first experiment, glyphosate was sprayed each three months to avoid cover crops. This treatment was compared with naturally occurring vegetation during the year and the use of Avena sativa in the winter. In a second experiment, Stizolobium aterrimum was cultivated during the summer compared with naturally occurringvegetation. Brazilian ground pearl population was higher in glyphosate sprayed areas than where cover

  7. Effects of legume cover crop and sub-soiling on soil properties and Maize (Zea mays L) growth in semi arid area of Machakos district, Kenya = Efecto del cultivo de cobertua y el subsolado sobre las propiedades del suelo y crecimiento de maiz (Zea mays L.) en la region semi arida de Machakos, Kenia

    NARCIS (Netherlands)

    Karuma, A.; Gachene, C.K.K.; Gicheru, P.; Mwangombe, A.W.; Mwangi, H.W.; Clavel, D.; Verhagen, A.; Kaufmann, Von R.; Francis, J.; Ekaya, W.

    2011-01-01

    Low crop yields in the semi arid areas of Kenya have been attributed to, among other factors, low soil fertility, low farm inputs, labour constraints and inappropriate tillage practices that lead to pulverized soils. The aim of this study was to determine the effects of legume cover crops (LCC) on

  8. Produtividade e composição de uva e de vinho de videiras consorciadas com plantas de cobertura Productivity and composition of grapes and wine of vines intercropped with cover crops

    Directory of Open Access Journals (Sweden)

    Jovani Zalamena

    2013-02-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência de plantas de cobertura verde sobre a produtividade das videiras e sobre a composição da uva e do vinho. Durante duas safras, foram feitas avaliações de três tipos de consórcio, dois manejos das coberturas e de um tratamento controle, com plantas espontâneas controladas por herbicidas e roçagem. Utilizou-se vinhedo de uvas 'Cabernet Sauvignon', localizado a 1.130 m de altitude, em um Cambissolo Húmico distrófico, em São Joaquim, SC. Os consórcios foram realizados com a sucessão de cultivos anuais de moha (Setaria italica com azevém (Lolium multiflorum e de trigo mourisco (Fagopyrum esculentum com aveia‑branca (Avena sativa, bem como com a planta perene festuca (Fetusca sp.. Os manejos consistiram da transferência ou não do resíduo cultural da linha para a entrelinha. As videiras apresentaram maior produtividade de uva no consórcio com as plantas anuais, em comparação ao tratamento controle, ou com a planta perene festuca. O manejo da cobertura verde não teve influência sobre as variáveis avaliadas. Os consórcios não influenciaram de forma consistente os teores de N da uva nem a composição do mosto, embora, na última safra, o teor de sólidos solúveis totais do mosto tenha sido maior nos tratamentos com consórcio, em comparação ao controle. Além disso, as videiras consorciadas com festuca podem proporcionar vinho com maior teor de antocianinas e polifenóis totais.The objective of this work was to evaluate the influence of green cover crops on vine productivity and on grape and wine composition. For two growing seasons, evaluations were done for three intercrops, two managements of the cover crops, and for a control treatment with weeds controlled by herbicides and mowing. A vineyard of 'Cabernet Sauvignon', located at 1,130 m altitude in a Haplumbrept soil, in São Joaquim, SC, Brazil was used. Intercropping was done with a succession of the cover crops moha

  9. Adubação nitrogenada para milho com o uso de plantas de cobertura e modos de aplicação de calcário Forms of lime application, cover crops and nitrogen rates in maize

    Directory of Open Access Journals (Sweden)

    Aguinaldo José Freitas Leal

    2013-04-01

    Full Text Available O sistema plantio direto (SPD é uma realidade na região dos Cerrados, mas alguns questionamentos persistem nesse tipo de manejo como o modo de realização da calagem e a dose de nitrogênio (N a ser adotada em cultura comercial, em relação às culturas precedentes. Desse modo, objetivou-se avaliar modos de aplicar o calcário na implantação do SPD e o efeito de culturas de cobertura precedentes sobre a necessidade de adubação nitrogenada da cultura do milho, durante diferentes anos agrícolas. O delineamento experimental utilizado foi de blocos casualizados, em esquema fatorial 5 x 2 (modos de aplicação do calcário x culturas de cobertura e posterior divisão em três subparcelas, referentes às doses de N (0, 90 e 180 kg ha-1. Foram avaliados quatro modos de aplicação de calcário: incorporado a 0-0,2 m, em out./2001; dose total em superfície aplicada, em out./2001; aplicação de 1/2 da dose, em out./2001, e 1/2, em ago./2002, na superfície; e aplicação de 1/3 da dose recomendada, em mar./2001, + 1/3, em out./2001, e 1/3, em ago./2002, também em superfície. Além de um tratamento testemunha (sem calcário e duas culturas de cobertura, crotalária e milheto. Os diferentes modos de calagem não alteraram a produtividade de grãos de milho. O cultivo de milho após crotalária apresentou melhor desempenho e menor demanda de adubação nitrogenada, quando comparado ao cultivado após milheto.The no-tillage (NT management is widely used in the Cerrado region, but some questions remain unanswered, for example about the need of liming and adequate nitrogen rates for commercial crops when preceded by cover crops. Our objective was to evaluate the effect of precedent cover crops on the maize demand for nitrogen fertilization and forms of liming preceding the adoption of no-tillage management (NT in different growing seasons. The experiment was arranged in a randomized block factorial design 5 x 2 (liming forms x cover crops and

  10. Soil erosion and runoff response in almond orchards under two shrub cover-crops strips in a high slope in semi-arid environment

    International Nuclear Information System (INIS)

    Carceles-Rodriguez, B.; Francia-Martinez, J. R.; Martinez-Raya, A.; Duran-Zuazo, V. H.; Rodriguez-Pleguezuelo, C. R.; Casado-Mateos, J. P.

    2009-01-01

    Soil erosion is one of the main physical processes of land degradation in Spain. Several studies in the Mediterranean environment have demonstrated the positive effect of vegetation covers on the reduction of water erosion and their indirect improvement of the soil physical and chemical properties, essentially by the incorporation of organic matter. (Author)

  11. Temperatura do solo em função do preparo do solo e do manejo da cobertura de inverno Soil temperature as affected by soil tillage and management of winter cover crops

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Angeli Furlani

    2008-02-01

    Full Text Available Com o objetivo de avaliar o efeito do preparo do solo e do manejo da cobertura de inverno (consórcio aveia-preta + nabo forrageiro sobre a temperatura do solo, realizou-se um experimento em um Nitossolo em Botucatu-SP no outono/inverno de 2000. Utilizou-se um delineamento em blocos casualizados em esquema fatorial 3 x 3 (três preparos e três manejos. O preparo do solo constou de: preparo convencional, preparo conservacionista com escarificação e plantio direto, e o manejo da cobertura: consórcio dessecado, rolado e triturado. Foram avaliados a temperatura do solo (termopares a 5 cm de profundidade, de hora em hora, aos 7, 14, 30, 45 e 60 dias após a emergência das plantas do consórcio; o teor de água do solo na profundidade de 10 cm, nas mesmas épocas; e a cobertura do solo (massa seca e índice de cobertura, imediatamente após aplicação dos tratamentos. O sistema plantio direto apresentou temperaturas do solo menores que as do preparo convencional, até o 14º dia após emergência (DAE das plantas. A partir do 30° DAE das plantas, a temperatura não foi mais influenciada pelos tratamentos, devido à cobertura do consórcio e ocorrência de boa disponibilidade de água no solo. Os manejos da cobertura com rolo-faca, triturador e herbicida não influenciaram a temperatura do solo. A temperatura do solo não interferiu no crescimento e desenvolvimento das culturas de cobertura.To evaluate the effect of soil tillage and management of winter cover crops (black oat + radish intercrop on the soil temperature, an experiment was conducted in a Nitossol (Alfisol in Botucatu, state of São Paulo, Brazil, in the 2000 fall/winter season. A design in randomized blocks was used in a 3 x 3 factorial scheme (three tillage and three cover crop managements. Soil tillage consisted of: conventional tillage, conservation tillage with chiseling, and no-tillage. The cover crops managements included plant killing with post-emergence herbicide, rolling

  12. Atributos biológicos do solo sob influência da cobertura vegetal e do sistema de manejo Soil biological attributes influenced by cover crops and management systems

    Directory of Open Access Journals (Sweden)

    Mozaniel Batista da Silva

    2007-12-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos de culturas de cobertura e dos sistemas plantio direto (PD e convencional (PC sobre indicadores biológicos do solo, cultivado com feijoeiro-comum, no inverno, sob irrigação. O experimento foi conduzido em Santo Antônio de Goiás, GO, em Latossolo Vermelho distrófico textura argilosa. Culturas de cobertura foram implantadas anualmente no verão, desde 2001, sendo utilizadas a braquiária, guandu, milheto, capim-mombaça, sorgo, estilosantes, braquiária consorciada com milho, e mata nativa, como tratamento referência. Em 2005, 60 dias após o corte das culturas de cobertura foi implantada a cultura do feijoeiro, cultivar BRS Valente, sob irrigação, com semeadura realizada em 16/6/2005 e colheita efetuada em 19/9/2005. Coletaram-se amostras de solo, na profundidade de 0-10 cm, em três épocas: novembro de 2004 (pré-plantio das culturas de coberturas, junho (pré-plantio do feijoeiro e julho (florescimento do feijoeiro de 2005. Avaliaram-se a respiração basal, o carbono e o nitrogênio da biomassa microbiana, a razão carbono da biomassa microbiana/carbono orgânico, a razão nitrogênio da biomassa microbiana/nitrogênio total e o quociente metabólico do solo. Esses atributos biológicos do solo são influenciados pelas culturas de cobertura, manejo do solo e épocas de amostragem.The objective of this work was to evaluate the effects of cover crops and direct and conventional tillage systems on soil biological attributes when cultivated with dry bean in winter under sprinkle irrigation. The experiment was conducted in Santo Antônio de Goiás, GO, Brazil, in a clayey Rhodic Haplustox. Cover crops were cultivated annually in the summer since 2001, using Brachiaria brizantha, Cajanus cajan, Pennisetum glaucum, Panicum maximum, sorghum, Stylosanthes guianensis, brachiaria in association with corn, and native vegetation as reference. In 2005, 60 days after cutting the cover crops, BRS

  13. Factors associated with Leguminous Green Manure Incorporation and Fusarium wilt suppression in watermelon

    Science.gov (United States)

    A fall planted Vicia villosa cover crop incorporated in spring as a green manure can suppress Fusarium wilt [Fusarium oxysporum f. sp. niveum (FON)] of watermelon in Maryland and Delaware. Experiments were conducted to determine whether the mechanism of this suppression was general or specific, and ...

  14. EFEITO DA COBERTURA VEGETAL DO SOLO SOBRE A ABUNDÂNCIA E DIVERSIDADE DE INIMIGOS NATURAIS DE PRAGAS EM VINHEDOS EFFECTS OF COVER CROPS ON THE ABUNDANCE AND DIVERSITY OF NATURAL ENEMIES OF GRAPEVINE PEST

    Directory of Open Access Journals (Sweden)

    MARCOS ANTÔNIO MATIELLO FADINI

    2001-12-01

    Full Text Available O controle de pragas da videira no Brasil restringe-se basicamente ao uso de inseticidas, devido à inexistência de trabalhos que visem a complementar o manejo de pragas através de controle biológico. Neste trabalho, objetivou-se verificar o efeito de diferentes coberturas vegetais nas entrelinhas de plantio de videira sobre a abundância e diversidade de potenciais inimigos naturais de pragas da videira no município de Caldas, região Sul do Estado de Minas Gerais. Foram testadas sete diferentes coberturas de solo (aveia-preta, aveia-preta e ervilhaca, ervilhaca, cobertura morta, uso de herbicida, capina mecânica e mato roçado. A cobertura vegetal do solo influenciou tanto a diversidade quanto a abundância de inimigos naturais, sendo o consórcio de aveia-preta e ervilhaca, cultivadas simultaneamente, o tratamento que proporcionou maior diversidade e abundância de inimigos naturais. Assim, a cobertura vegetal do solo pode, potencialmente, ser um componente importante em programas de manejo integrado de pragas na cultura da videira.The control of grapevine pests in Brazil is only based in the use of chemical products. It is due to the whole absence of experimental works developed to test and evaluate alternative control systems, like the biological control. The objective of this work was to evaluate the effect of different types of cover crops, placed between the cultivation lines of grapevine, in the abundance and diversity of natural control arthropods of grapevine pests. The experiment was conduced in the EPAMIG, Caldas Research Farm, located in the Minas Gerais State, Brazil. They Were tested seven different systems of soil covering. The presence of vegetal covering was beneficial to improve the diversity as well as the abundance of biological control agents present on the grapevine crop. The cultivation of black oat and pea together, was the treatment that showed the better result to diversity and abundance. Therefore, the cover

  15. Upland rice yield as affected by previous summer crop rotation (soybean or upland rice and glyphosate management on cover crops Produtividade do arroz de terras altas afetada pela rotação de cultura e pelo manejo de glifosato nas plantas de cobertura do solo

    Directory of Open Access Journals (Sweden)

    A.S Nascente

    2013-03-01

    Full Text Available The appropriate chemical management of cover crops in no-tillage aims to obtain greater benefits with its employment in agricultural systems. The objective of this study was to assess upland rice yield as affected by the previous summer crop, species and desiccation timing of cover crops by glyphosate. Sown cover crops were sown (November 2007, followed by rice in half of the experimental area and soybean in the other half (November 2008. After the harvesting of these crops, the same cover crops were sown again (March 2009 and followed by upland rice in the total area (November 2009. The experiment consisted of the combination of five cover crops (fallow, Panicum maximum, Brachiaria ruziziensis, B. brizantha and Pennisetum glaucum, four desiccation timings (30, 20, 10 and 0 days before rice sowing, and two antecedents of the summer crop (rice or soybean under no-tillage system (NTS, plus two control treatments at conventional tillage system (CTS. Cover crops significantly affect rice grain yield and its components. There is a significant tendency to highest yield when cover crop desiccation is conducted farther from the rice sowing date (from 2,577.1 kg ha-1 - desiccation at rice sowing to 3,115.30 kg ha-1 - desiccation 30 days before rice sowing. Soybean as an antecedent of summer crop allows better upland rice yield (3,754 kg ha-1 than rice as an antecedent of summer crop (2,635 kg ha-1; fallow/soybean/fallow (4,507 kg ha-1 and millet/soybean/millet (4,765 kg ha-1 rotation at no-tillage system, and incorporated fallow /soybean/ incorporated fallow (4,427 kg ha-1 at conventional tillage system allow the highest rice yield; upland rice yield is similar at no-till (3,194 kg ha-1 and till system (2,878 kg ha-1.O correto manejo químico das plantas de cobertura visa obter maiores benefícios com a sua introdução nos sistemas agrícolas. O objetivo deste estudo foi avaliar como a produção do arroz de terras altas é afetada pela safra de ver

  16. Development and Characterization of Transcription Factor Gene-Derived Microsatellite (TFGM) Markers in Medicago truncatula and Their Transferability in Leguminous and Non-Leguminous Species.

    Science.gov (United States)

    Liu, Wenxian; Jia, Xitao; Liu, Zhimin; Zhang, Zhengshe; Wang, Yanrong; Liu, Zhipeng; Xie, Wengang

    2015-05-15

    Transcription factors (TFs) are critical adaptor molecules that regulate many plant processes by controlling gene expression. The recent increase in the availability of TF data has made TFs a valuable resource for genic functional microsatellite marker development. In the present study, we developed TF gene-derived microsatellite (TFGM) markers for Medicago truncatula and assessed their cross-species transferability. A total of 203 SSRs were identified from 1467 M. truncatula TF coding sequences, 87.68% of which were trinucleotide repeats, followed by mono- (4.93%) and hexanucleotide repeats (1.48%). Further, 142 TFGM markers showed a high level of transferability to the leguminous (55.63%-85.21%) and non-leguminous (28.17%-50.00%) species. Polymorphisms of 27 TFGM markers were evaluated in 44 alfalfa accessions. The allele number per marker ranged from two to eight with an average of 4.41, and the PIC values ranged from 0.08 to 0.84 with an average of 0.60. Considering the high polymorphism, these TFGM markers developed in our study will be valuable for genetic relationship assessments, marker-assisted selection and comparative genomic studies in leguminous and non-leguminous species.

  17. Evaluating the nodulation status of leguminous species from the Amazonian forest of Brazil.

    Science.gov (United States)

    de Faria, Sergio M; Diedhiou, Abdala G; de Lima, Haroldo C; Ribeiro, Robson D; Galiana, Antoine; Castilho, Alexandre F; Henriques, João C

    2010-06-01

    Numerous leguminous species are used or have potential uses for timber production, pharmacological products, or land reclamation. Through N(2)-fixation, many leguminous trees contribute to the N-balance of tropical wetlands and rainforests. Therefore, studies of the N(2)-fixation ability of leguminous species appear to be crucial for the better use and conservation of these resources. The global nodulation inventory in the Leguminosae family is constantly being enriched with new records, suggesting the existence of undiscovered nodulated species, especially in tropical natural ecosystems and other hot spots of biodiversity. In this respect, the nodulation of leguminous species from the Amazonian forest of Porto Trombetas (Brazil) was surveyed. Overall, 199 leguminous species from flooded and non-flooded areas, were examined for their nodulation status by combining field observations, seedling inoculations, and screening of N(2)-fixing bacterial strains from the collected nodules. The results revealed a tendency for a higher relative frequency of nodulation in the species from the flooded areas (74%) compared with those from the non-flooded areas (67%). Nodulation was observed in the Caesalpinioideae, Mimosoideae, and Papilionoideae, with 25, 88, and 84% of the examined species in each subfamily, respectively. Of the 137 nodulated leguminous species, 32 including three Caesalpinoideae, 19 Mimosoideae, and 10 Papilionoideae are new records. One new nodulated genus (Cymbosema) was found in the Papilionoideae. Twelve non-nodulating leguminous species were also observed for the first time. The results are discussed based on the systematics of the Leguminosae family and the influence of available nutrients to the legume-bacteria symbiosis.

  18. Ferric Leghemoglobin in Plant-Attached Leguminous Nodules.

    Science.gov (United States)

    Lee, Kk.; Shearman, L. L.; Erickson, B. K.; Klucas, R. V.

    1995-01-01

    Leghemoglobin (Lb) is essential for nitrogen fixation by intact leguminous nodules. To determine whether ferric Lb (Lb3+) was detectable in nodules under normal or stressed conditions, we monitored the status of Lb in intact nodules attached to sweet clover (Melilotus officinalis) and soybean (Glycine max [L.] Merr.) roots exposed to various conditions. The effects of N2 and O2 streams and elevated nicotinate levels on root-attached nodules were tested to determine whether the spectrophotometric technique was showing the predicted responses of Lb. The soybean and sweet clover nodules' Lb spectra indicated predominantly ferrous Lb and LbO2 in young (34 d) plants. As the nodule aged beyond 45 d, it was possible to induce Lb3+ with a 100% O2 stream (15 min). At 65 d without inducement, the nodule Lb status indicated the presence of some Lb3+ along with ferrous Lb and oxyferrous Lb. Nicotinate and fluoride were used as ligands to identify Lb3+. Computer-calculated difference spectra were used to demonstrate the changes in Lb spectra under different conditions. Some conditions that increased absorbance in the 626 nm region (indicating Lb3+ accumulation) were root-fed ascorbate and dehydroascorbate, plant exposure to darkness, and nodule water immersion. PMID:12228593

  19. Accumulation and function of trigonelline in non-leguminous plants.

    Science.gov (United States)

    Ashihara, Hiroshi; Watanabe, Shin

    2014-06-01

    As part of our studies of the occurrence, biosynthesis, function and human use of trigonelline, we looked at trigonelline-accumulating plant species and at the distribution of trigonelline in different organs of trigonelline-accumulating non-leguminous plants. There are many trigonelline-synthesizing plant species, but apart from legume seeds only a few species accumulate high concentrations of trigonelline. We have found only three species that accumulate high levels of trigonelline: Murraya paniculata (orange jessamine), Coffea arabica (coffee) and Mirabilisjalapa (four o'clock flower). Trigonelline was found in all parts of Murraya paniculata seedlings at 4-13 micromol/g fresh weight; more than 70% was distributed in the leaves. In the coffee plant, trigonelline was found in all organs, and the concentrations in the upper stems, including tips (48 micromol/g FW) and seeds (26 micromol/g FW), were higher than in other organs. In Mirabilis jalapa plants, trigonelline was found in leaves, stems, flowers, roots and seeds; the concentration varied from 0.3 to 13 micromol/g FW and was generally higher in young tissues than in mature tissues, except for seeds. Exogenously supplied nicotinamide increases the trigonelline content. The in planta role of trigonelline and the possible use oftrigonelline-accumulating plants in herbal medicine are discussed.

  20. Scanning electron microscopy in characterizing seeds of some leguminous trees

    Science.gov (United States)

    Ghosh, Nabarun; Chatterjee, Amiyanghshu; Smith, Don W.

    2009-05-01

    SEM has greatly increased our knowledge of the microstructure of seeds. Mature seed coats are rather thick walled and stable in a vacuum: this allows quick preparation for SEM examination, without the need of complicated dehydration techniques. The low level of technical expenditure required, in combination with the high structural diversity exhibited and the intuitive ability to understand the "three dimensional", often aesthetically appealing micro-structures visualized, has turned seed-coat studies into a favorite tool of many taxonomists. We used dry mature seeds of 26 species of 4 Leguminous genera, Acacia, Albizia, Cassia and Dalbergia to standardize a procedure for identifying the seeds through SEM on the seed surface and seed sections. We cut transverse and longitudinal sections of the seeds and observed the sections from different regions of seeds: midseed, near the hilum and two distal ends. Light microscopy showed the color, texture, pleurograms, fissures and hilum at lower magnification. The anatomical study with SEM on the seed sections revealed the size, shape, and number of tiers and cellular organization of the epidermis, hypodermis, endosperm and internal structural details. We found the ornamentation pattern of the seeds including undulations, reticulations and rugae that were species specific. Species of Dalbergia (assamica, latifolia and sissoo), Albizia (odoratissima and procera), Acaia (arabica and catechu) and Cassia (glauca, siamia and spectabilis) are difficult to distinguish externally, but SEM studies provided enough characteristic features to distinguish from the other. This technique could be valuable in identifying seeds of important plant species for conservation and trading.

  1. Modelagem da proteção do solo por plantas de cobertura no sul de Minas Gerais = Modeling of soil protection by cover crops in southern Minas Gerais, Brazil.

    Directory of Open Access Journals (Sweden)

    Diego Antonio França de Freitas

    2012-08-01

    Full Text Available A cobertura do solo é o fator de maior importância relativa no controle da erosão hídrica. Assim, objetivou-se no presente estudo elaborar a modelagem da cobertura vegetal de vinte e quatro plantas de cobertura, em diversos sistemas de plantio e históricos de uso, com potencial para cultivo no Sul de Minas Gerais. Para avaliação da cobertura vegetal foram realizadas avaliações no campo utilizando uma régua de classificação da cobertura vegetal, sendo o delineamento experimental inteiramente casualizado, com três repetições, utilizado neste experimento. As plantas cultivadas sobre a palhada de feijãoirrigado apresentaram alto índice de cobertura do solo, o que pode estar relacionado à maior disponibilidade de nutrientes deixado por esta cultura na palhada e a maior reserva de água no solo, promovido pela irrigação do feijão. O milheto cultivado em nível e sobre a palhada de milheto e feijão-de-porco apresentou o menor índice de cobertura entre as plantas testadas. Na região sul de Minas Gerais os padrões de chuvas ocorrem em maior quantidade nos períodos de outubro a março, com elevação em dezembro e janeiro. Neste período o solo deve estar protegido do impacto da gota de chuva, pois o risco de erosão hídrica é maior. Assim, a utilização das plantas de cobertura é de grande importância, pois estas protegem o solo do impacto direto dasgotas de chuvas e diminuem os picos de temperatura do solo, sendo que estas devem ser cultivadas, preferencialmente, sobre a palhada de feijão.The ground cover is the most important factor relative to control erosion. Thus, the objective of this study was to develop a model plant cover for 24 cover crops used in several cropping systems and historical use, with potential for cultivation in southern Minas Gerais State, Brazil. To evaluate the vegetation cover field assessments using the strip land cover classification. A completely randomized design with three replications was

  2. Best Accuracy Land Use/Land Cover (LULC Classification to Derive Crop Types Using Multitemporal, Multisensor, and Multi-Polarization SAR Satellite Images

    Directory of Open Access Journals (Sweden)

    Christoph Hütt

    2016-08-01

    Full Text Available When using microwave remote sensing for land use/land cover (LULC classifications, there are a wide variety of imaging parameters to choose from, such as wavelength, imaging mode, incidence angle, spatial resolution, and coverage. There is still a need for further study of the combination, comparison, and quantification of the potential of multiple diverse radar images for LULC classifications. Our study site, the Qixing farm in Heilongjiang province, China, is especially suitable to demonstrate this. As in most rice growing regions, there is a high cloud cover during the growing season, making LULC from optical images unreliable. From the study year 2009, we obtained nine TerraSAR-X, two Radarsat-2, one Envisat-ASAR, and an optical FORMOSAT-2 image, which is mainly used for comparison, but also for a combination. To evaluate the potential of the input images and derive LULC with the highest possible precision, two classifiers were used: the well-established Maximum Likelihood classifier, which was optimized to find those input bands, yielding the highest precision, and the random forest classifier. The resulting highly accurate LULC-maps for the whole farm with a spatial resolution as high as 8 m demonstrate the beneficial use of a combination of x- and c-band microwave data, the potential of multitemporal very high resolution multi-polarization TerraSAR-X data, and the profitable integration and comparison of microwave and optical remote sensing images for LULC classifications.

  3. Forages and Pastures Symposium: Cover Crops in Livestock Production: Whole-System Approach: Managing Grazing to Restore Soil Health And farm livelihoods.

    Science.gov (United States)

    Teague, W R

    2018-02-01

    To ensure long-term sustainability and ecological resilience of agro-ecosystems, agricultural production should be guided by policies to ensure regenerative cropping and grazing management protocols. Changing current unsustainable high-input agricultural practices to low-input practices that regenerate ecosystem function will be necessary for sustainable, resilient agro-ecosystems. Effective soil management provides the greatest potential for achieving sustainable use of agricultural land with rapidly changing, uncertain and variable climate. With appropriate management of grazing enterprises, soil function can be regenerated to improve essential ecosystem services and farm profitability. Affected ecosystem services include carbon sequestration, water infiltration, soil fertility, nutrient cycling, soil formation, biodiversity, wildlife habitat, and increased ecosystem stability and resilience. Collectively, conservation agriculture managed regeneratively supports ecologically healthy, resilient agro-ecosystems and enhances watershed function. To accomplish this, it is important for scientists to partner with farmers who have improved the environment and excel financially to convert experimental results into sound environmental, social and economic benefits regionally and globally. Benefits include: addressing questions at commercial scale; integrating component science into whole-system responses; identifying emergent properties and unintended consequences; incorporating pro-active management to achieve desired goals under changing circumstances; and including the potential of the human element to achieve superior economic and environmental goals. Developing and implementing regenerative management protocols that include ruminant grazing animals will be necessary to ensure long-term sustainability and ecological resilience of agro-ecosystems. © The Author(s) 2018. Published by Oxford University Press on behalf of American Society of Animal Science. All rights

  4. Atributos químicos do solo e produtividade de videiras alterados pelo manejo de coberturas verdes na Serra Gaúcha Soil chemical properties and grapevine yield affected by cover crop management in Serra Gaucha, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Jaqueline Dalla Rosa

    2009-02-01

    Full Text Available O manejo do solo pode interferir na disponibilidade de nutrientes e na produtividade de frutos. O objetivo deste estudo foi avaliar o efeito de formas de manejo da fitomassa de diferentes espécies de plantas de cobertura verde sobre características químicas do solo, relacionadas à matéria orgânica e à disponibilidade de nutrientes, e sobre a produtividade de uva. O experimento foi realizado na Embrapa Uva e Vinho, em Bento Gonçalves, RS, sobre um Cambissolo Háplico, num parreiral implantado em 1989, com os cultivares Niágara Branca e Niágara Rosada, no sistema de latada. Os tratamentos testados foram implantados em 2002 e consistiram em três coberturas vegetais: vegetação espontânea, aveia-preta e consórcio de trevo-branco + trevo-vermelho + azevém; e dois sistemas de manejo: dessecado com herbicida e roçado, os quais foram realizados no outono, previamente à ressemeadura das espécies. O delineamento experimental foi de blocos ao acaso com três repetições. Os atributos químicos indicadores da acidez e da disponibilidade de nutrientes no solo foram pouco influenciados pelas espécies de cobertura. A dessecação das plantas aumentou os teores de Ca e Mg trocáveis, P disponível e C orgânico total em relação ao manejo roçado. A produtividade de uva nas safras de 2004 e 2006 foi baixa em relação ao potencial dos cultivares, possivelmente por restrições climáticas, contudo foi maior quando se utilizou a aveia como planta de cobertura do que com o consórcio de plantas.Soil management can have effects on nutrient availability and fruit yield. The objective of this study was to evaluate the effect of phytomass management forms of different cover crop species on soil chemical properties related to organic matter, nutrient availability, and on grapevine yields. The experiment was carried out in Embrapa Uva e Vinho, in Bento Gonçalves, RS, in Southern Brazil, on a Haplic Cambissol, in a vineyard established in 1989

  5. Soybean production and carpogenic germination of Sclerotinia sclerotiorum under different cover cropsProdução de soja e germinação carpogênica de Sclerotinia sclerotiorum sob diferentes coberturas de solo

    Directory of Open Access Journals (Sweden)

    Luciano Reis Venturoso

    2013-05-01

    Full Text Available The aim of this work was to evaluate the influence of different soil cover crops on the carpogenic germination of Sclerotinia sclerotiorum and the development and yield of soybean. The treatments consisted of mulches of brachiaria, canola, safflower, crambe, sunflower and forage radish mulch, and a control with no cover mulch. The crops were sown in pots containing 4.4 dm³ of soil type Rhodic Acrustox. After 45 days the plant material was cut into pieces in order to standardize the amount of straw to 2800 kg ha-1. Soybean seeds were sown and seven days after seedling emergence two sclerotia were allocated in each pot. With regard to carpogenic germination, we analyzed the time to germination of sclerotia and formation of apothecia, number of stipes and apothecia per sclerotia and the percentage apothecia formed. In the soybean crop was determined plant height at flowering and harvest, relative chlorophyll index, dry matter mass and root, number of pods per plant, number of seeds per pod, grain yield, number of nodules per plant and dry mass of nodules. With the exception of safflower mulch, the use of cover crops reduced the formation of stipes and apothecia of S. sclerotiorum. The covers with brachiaria, sunflower and forage radish mulch increased by 16, 10 and 6 days respectively the overall period of apothecium formation, but only brachiaria reduced the percentage of apothecia formed. The sunflower mulch hindered soybean development and yield. O trabalho teve por objetivo avaliar a influência de diferentes coberturas vegetais de solo sobre a germinação carpogênica de Sclerotinia sclerotiorum e sobre o desenvolvimento e rendimento da cultura da soja. Os tratamentos constaram da palhada de braquiária, canola, cártamo, crambe, girassol e nabo forrageiro, mais um controle sem cobertura. As culturas de cobertura foram semeadas em vasos contendo 4,4 dm³ de solo do tipo Latossolo Vermelho Distroférrico. Após 45 dias o material vegetal foi

  6. DAMPAK FASILITATIF TUMBUHAN LEGUM PENUTUP TANAH DAN TANAMAN BERMIKORIZA PADA SUKSESI PRIMER DI LAHAN BEKAS TAMBANG KAPUR (Facilitative Impacts of Legume Cover-crop and Mycorrhizal-inoculated Plant on Primary Succession of Limestone Quarries

    Directory of Open Access Journals (Sweden)

    Retno Prayudyaningsih

    2015-11-01

    melalui peningkatkan kerapatan individu dan keanekaragaman jenis pada semua tingkatan habitus, meskipun untuk tingkat herba dan semak, kerapatan individu dan keanekaragaman jenis terendah pada areal pertanaman tanpa mikoriza. ABSTRACT Limestone mining using open pit mining method that involves vegetation removal and soil drilling and blasting in accessing limestone material has caused ecosystem damages. Natural recovery of such a harsh site is a slow process as the site condition in the successional process do not favor the natural vegetation development. Plants Establishment could facilitate other plants by ameliorating harsh environmental characteristics and/or increasing the availability of nutrient resources. Facilitation impact of legume cover crop (Centrosema pubescens and mycorrhizal-inoculated plantation (Vitex cofassus was studied on primary succession of TNS limestone mining quarry. The emergence of natural plants is measured using individual density, diversity and number of species by quadrat systematic plot method base on their habitus. Site conditions measured by litterfall thickness and biomass, soil organic matter content and soil organic carbon levels. The study was conducted in four types of areas on limestone postmining lands are open areas/natural conditions without planting, legume cover crop area, non mycorrhizal-inoculated plant area and mycorrhizal-inoculated plant area. The results indicated, establishment of legume cover crops and mycorrhizal-inoculated plants improved site conditions of limestone quarry. Legume cover crops establishment produced a large amount of litters with 1.08 cm of a thickness and 188.96 g/m2 of biomass, and it’s subsequent decomposition increased soil organic matter of 3.80% and the organic carbon content of 2.20%. Plantation formation gave similar impact as well, particulary those inoculated with Arbuscula Mycorrhizae Fungi (AMF produced amount of litters with 1.32 cm of a thickness and 220.48 g/m2 of biomass, with 3

  7. ANTIFUNGAL POTENTIAL OF LEAF EXTRACTS OF LEGUMINOUS TREES AGAINSTSCLEROTIUM ROLFSII.

    Science.gov (United States)

    Sana, Nighat; Shoaib, Amna; Javaid, Arshad

    2016-01-01

    Sclerotium rolfsii Sacc. is a destructive soil-borne plant pathogen that infects over 500 plant species and causes significant yield losses in many economically important plant species. Synthetic fungicides used to combat the menace also pollute the environment and cause health hazards. In order to search environmental friendly alternatives from natural resources, methanolic extracts of three leguminous tree species namely Acacia nilotica (L.) Willd. ex Delile subsp. indica (Benth.) Brenan, Prosopis juliflora (Sw.) DC. and Albizia lebbeck (L.) Benth. were evaluated for their antifungal activity against S. rolfsii and A. nilotica subsp. indica exhibited the maximum fungicidal potential. Two hundred grams dried leaf material of each of the three test plant species were extracted with methanol for two weeks. After filtration, methanol was evaporated on a rotary evaporator. Malt extract broth was used to make various concentrations of the crude methanolic extracts and their antifungal potential was determined by comparing the fungal biomass in various treatments with control. Chemical composition of methanolic leaf extract of A. nilotica subsp. indica was determined through GC-MS analysis. Methanolic leaf extract of A. nilotica subsp. indica showed the highest fungicidal activity. Fungal biomass was decreased by 17-55% due to various concentrations of this extract over control. Different concentrations of P. juliflora reduced fungal biomass by 3-52%. Fourteen compounds were identified in methanolic extract of A. nilotica subsp. indica . 9,12,15-octadecatrienoic acid, methyl ester, (Z,Z,Z,)- (16.59%) was the most abundant compound followed by 1-pentanol, 2 methyl-, acetate (14.80%); hexanedioic acid, dimethyl ester (13.10%) and cyclotriaconta- 1, 7, 16, 22-tetraone (10.28%). This study concludes that methanolic leaf extract of A. nilotica subsp. indica can be used for management of S. rolfsii .

  8. Concomitant sensitization to legumin, Fag e 2 and Fag e 5 predicts buckwheat allergy

    DEFF Research Database (Denmark)

    Geiselhart, S; Nagl, C; Dubiela, P

    2018-01-01

    pattern in sera from allergic patients when compared to sensitized individuals. Several IgE-reactive proteins were purified from crude buckwheat extract, namely legumin (Fag e 1 plus its large subunit), Fag e 2 (2S albumin), and newly identified Fag e 5 (vicilin-like) as well as hevein-like antimicrobial...... vicilin-like protein as a new relevant marker allergen, designated Fag e 5. Additionally, another new allergen, Fag e 4, potentially important for cross-reactivity to latex was added to the allergen panel of buckwheat. Further, our data show that the full-length legumin comprising both, large and small...... subunit should be applied for component resolved diagnosis. Our data indicate that concomitant sensitization to legumin, Fag e 2 and Fag e 5 predicts buckwheat allergy. This article is protected by copyright. All rights reserved....

  9. [Immunity of a leguminous plant infected by nodular bacteria Rhizobium spp. F.

    Science.gov (United States)

    Glyan'ko, A K; Ischenko, A A

    2017-01-01

    Recent studies of the immune system of leguminous plants infected with nodular bacteria (rhizobia) are summarized. The possibility of blocking the invasion of rhizobia into plant organs not affected by the primary infection is discussed. The concept of local and systemic resistance of the leguminous plant to rhizobial infection is introduced. The Nod factors of rhizobia are considered, as well as the plant receptors that interact with these factors upon the formation of symbiosis of the plant and bacteria. The role of bacterial surface exopolysaccharides in the suppression of the protective system of the plants is discussed. The innate immunity of leguminous plant cells is assumed to affect the formation and functioning of the symbiosis of the plant and the bacteria.

  10. Reproductive Indicators of Leguminous Plants as a Characteristic of the Ecological State of Urban Areas

    Science.gov (United States)

    Zamaletdinov, R. I.; Okulova, S. M.; Gavrilova, E. A.; Zakhvatova, A. A.

    2018-01-01

    This article examines the results of many years of research on the reproductive performance of six species of leguminous plants (FabaceaeLind., 1836) under conditions of urbanization of habitat (Kazan). The range of variability of the main reproductive indices in six species is illustrated: the potential productivity, the actual productivity of the six main types of leguminous plants. The features of variability of seed death at different stages of development are shown depending on habitat conditions. It is established that the main regularities of changes in reproductive parameters depending on habitat conditions are manifested both in native species and in the introduced species Caraganaarborescens Lam., 1785. Based on the results of the study we made conclusion about the advisability of monitoring the reproductive parameters of leguminous plants for indicating the state of the environment in a large city.

  11. Decomposição de resíduos vegetais em latossolo sob cultivo de milho e plantas de cobertura Decomposition of plant residues in latosol under corn crop and cover crops

    Directory of Open Access Journals (Sweden)

    Arminda Moreira de Carvalho

    2008-12-01

    .Soil degradation occurs as a consequence of intensive preparation associated with monocropping systems with deposition of residues that are rapidly decomposed. The objective of this study was to investigate the decomposition rates of different cover plants residues in Latosol (Oxisol under conventional and no-tillage systems. The cover plants (Crotalaria juncea, Canavalia brasiliensis, Cajanus cajan, Mucuna pruriens, Helianthus annuus, Pennisetum glaucum, Raphanus sativus and natural fallow, as a control were used in a succession with maize. The cover plants were cut when flowering reached approximately 50 % and remained on the soil until the sowing of the maize. In the conventional system, plant residues were incorporated in subplots with plough. Litter bags with 10 g of dry matter of each species were placed on the soil surface and covered with plant residues to determine the decomposition rate along the dry (60 and 90 days of incubation and wet seasons (180, 210 and 240 days of incubation under both systems. During soil preparation and herbicide application before the sowing of maize, the remaining bags were removed from the field and kept in cold storage (0 ºC. After the sowing of maize, these bags were returned to the respective subplots, either on the surface for the no-tillage treatment or buried at 10 cm depth when under the incorporation treatment. The lowest decomposition rates were found for residues of Cajanus cajan Pennisetum glaucum, Mucuna pruriens, and natural fallow. Incorporation of plant residues accelerated the decomposition time, when compared to no-tillage system, except for Raphanus sativus. Maize yield was highest after the rotation with Canavalia brasiliensis.

  12. Plantas de cobertura e adubação nitrogenada na produção de milho em sistema de plantio direto Cover crops and nitrogen fertilization in corn production under no-tillage system

    Directory of Open Access Journals (Sweden)

    Abel W. de Albuquerque

    2013-07-01

    Full Text Available A utilização de plantas de cobertura do solo pode otimizar o aporte de material orgânico e nutrientes e proteger o solo dos processos erosivos enquanto o N é um dos nutrientes mais exigidos pelas culturas agrícolas, podendo tornar-se um fator limitante de seu rendimento. Neste contexto, realizou-se um experimento para avaliar a influência de três diferentes leguminosas usadas como plantas de cobertura sobre os componentes morfológicos e de produção do milho cultivado em sucessão sob sistema de plantio direto, na ausência e na presença de adubação nitrogenada mineral (80 kg ha-1 de N na forma de sulfato de amônio. O estudo foi desenvolvido em Latossolo Amarelo nos tabuleiros costeiros do estado de Alagoas. Os componentes de produção do milho apresentaram melhores resultados em sucessão à crotalária spectabilis. Constatou-se efeito da interação entre adubação verde e adubação nitrogenada resultando em maior produtividade de grãos para a cultura do milho.The cultivation of cover crops can optimize the input of organic material and nutrients and protect the soil from erosion, while the N is one of the most required nutrient by agricultural crops and may become a limiting fator in its productivity. In this context, an experiment was carried out to evaluate the influence of three different legumes used as cover crops on morphological components and production of corn grown in succession under no-tillage system, in the absence and presence of mineral N fertilization (80 kg N ha-1, in the form of ammonium sulfate. This study was conducted in an Oxissol of the Coastal Tablelands in the State of Alagoas. The components of maize production showed better results in succession to Crotalaria spectabilis. Significant interaction was found between green manure and N fertilization, resulting in higher grain productivity.

  13. Effect of guar crispbread with cereal products and leguminous seeds on blood glucose concentrations of diabetics.

    Science.gov (United States)

    Jenkins, D J; Wolever, T M; Taylor, R H; Barker, H M; Fielden, H; Jenkins, A L

    1980-01-01

    To compare the effect on blood glucose concentrations of guar incorporated into crispbreads with that of unprocessed high-fibre foods groups of four to six diabetics took a total of seven test breakfasts on separate days. By comparison with a breakfast of wholemeal bread and cheese, guar crispbread combined with bread reduced the area under the glucose response curve to 51% (p leguminous seeds may not make such meals more acceptable than meals of guar products, but a combination of leguminous seeds and guar may allow smaller and more acceptable amounts of both to be used. PMID:6253021

  14. Cultivos de cobertura,¿una alternativa viable para la región semirárida pampeana? Cover crops: a viable alternative for the semiarid Pampa region?

    Directory of Open Access Journals (Sweden)

    Romina Fernández

    2012-12-01

    N disponible en el suelo para el cultivo de maíz y sorgo. El rendimiento de maíz fue dependiente de la disponibilidad hídrica en el suelo a la siembra, ya que en B fue de 1015 kg ha-1, mientras que el rendimiento promedio con antecesor CC fue de 4044 kg ha-1. Para el caso del cultivo de sorgo, el manejo previo (con o sin CC no condicionó los rendimientos del mismo, debido a su ciclo fenológico más largo que facilitó que el cultivo aprovechara mayores precipitaciones específicamente durante el período entre siembra y floración.The effect of cover crops (CC on the provision of soil cover, N sequestration, accumulation of available water and the yield of a subsequent summer crop was evaluated. A field experiment with the following treatments was established: fallow without cover crop (B and rye as CC, control (CT, and fertilized (CF in a randomized complete block design with plots divided in two moments of drying of CC: July (CTJ and CFJ respectively and August (CTA and CFA respectively. On all treatments, two summer crops (CV, corn and sorghum were planted after fallowing at the end of November. Soil moisture and nitrate-N were determined at seeding of the CC, during their growing season, and at planting and flowering of corn and sorghum. Consumptive water use (UC and water use efficiency (EUA of CC, corn and sorghum were calculated. The standing biomass of CC was determined at the two dates of drying (J and A, and at planting of the summer crops and during their growing period the CC biomass litter was measured. The carbon (C, nitrogen (N and phosphorus (P contents of the dry matter were determined for all sampling dates. At planting of the summer crops, B treatment had less available water stored in the soil than CC, and J stored more water than A treatment. Total dry matter production of CC was higher in F and when dried in A. The CC sequestered important amounts of C, N and P, preventing potential leaching losses of N during the fallow, and CC litter

  15. Manejo de Conyza bonariensis resistente ao glyphosate: coberturas de inverno e herbicidas em pré-semeadura da soja Management of glyphosate resistant Conyza bonariensis: winter cover crops and herbicides in soybean pre-seeding

    Directory of Open Access Journals (Sweden)

    F.P. Lamego

    2013-06-01

    Full Text Available Conyza bonariensis tornou-se a principal planta daninha da cultura da soja no Sul do Brasil, em decorrência da evolução para resistência ao herbicida glyphosate. O objetivo deste trabalho foi avaliar o efeito de diferentes coberturas de inverno e da associação de manejo de dessecação pré-semeadura da soja, visando ao controle de C. bonariensis resistente ao glyphosate. Um experimento foi conduzido em campo, na safra 2010/2011. Os tratamentos foram conduzidos em esquema de parcelas subdivididas, em que as coberturas de inverno foram alocadas nas parcelas principais: aveia-preta, nabo, ervilhaca, azevém, trigo e pousio. Nas subparcelas, foram alocados os tratamentos de manejo de dessecação pré-semeadura da soja: glyphosate (720 g e.a ha-1, glyphosate (720 g e.a ha-1 + 2,4-D (1.050 g e.a ha-1, glyphosate (720 g e.a ha-1 + 2,4-D (1.050 g e.a ha-1/paraquat (200 g i.a ha-1 + diuron (100 g i.a ha-1, glyphosate (720 g e.a ha-1 + chlorimuron-ethyl (80 g i.a ha-1, glyphosate (720 g e.a ha-1 + chlorimuron-ethyl (80 g i.a ha-1/paraquat (200 g i.a ha-1 + diuron (100 g i.a ha‑1 e roçada. O nabo foi a espécie de cobertura que produziu o maior volume de massa seca durante o inverno, enquanto a ervilhaca foi a que apresentou maior efeito supressor sobre a germinação e o desenvolvimento inicial de C. bonariensis. Associações de glyphosate com 2,4-D ou chlorimuron-ethyl, seguidas da aplicação sequencial de paraquat + diuron, causaram maior redução na infestação de C. bonariensis.Conyza bonariensis became the main weed in soybean crop in Southern Brazil, as a consequence of the evolution of resistance to the herbicide glyphosate. The objective of this work was to evaluate the effect of different winter cover crops and the association of burn-down herbicides on the control of glyphosate-resistant C. bonariensis. A field experiment was conducted in the 2010/2011 season. The treatments were arranged in a split-plot scheme, with the winter

  16. Atributos químicos de solo sob produção orgânica influenciados pelo preparo e por plantas de cobertura Chemical attributes of soil under organic production as affected by cover crops and soil tillage

    Directory of Open Access Journals (Sweden)

    Eurâimi de Q Cunha

    2011-10-01

    Full Text Available Este trabalho objetivou determinar a influência das plantas de cobertura crotalária (Crotalaria juncea, guandu (Cajanus cajan (L. Millsp, mucuna-preta (Mucuna aterrima, sorgo vassoura (Sorgum technicum e pousio, nos atributos químicos de solo cultivado com feijão e milho orgânicos, sob semeadura direta (SD e preparo convencional (PC. O trabalho foi conduzido em Santo Antônio de Goiás, GO, em Latossolo Vermelho distrófico, no delineamento de blocos ao acaso, com quatro repetições. Em novembro de 2003 foram instalados quatro experimentos, dois em SD e dois em PC. Em cada preparo do solo um experimento foi conduzido com feijão e outro com milho. Amostragens de solo foram realizadas em setembro de 2003 e em novembro de 2007, nas camadas de 0-0,10 e 0,10-0,20 m. O pH e os teores de P, K+, Ca2+, Mg2+, Cu2+, Zn2+, Fe3+, Mn2+, H+ + Al³+ e M.O. foram analisadas e calculadas a capacidade de troca catiônica e a saturação por bases. Após quatro anos as plantas de cobertura não diferiram entre si quanto aos seus efeitos nos atributos químicos do solo; no entanto, elevaram o teor de M.O. em relação à condição inicial, seja sob SD ou sob PC. Em geral, a reciclagem dos nutrientes pelas plantas de cobertura não foi suficiente para a manutenção dos teores de P, K+, Fe3+ e Mn2+ no solo.This study aimed to determine the influence of the cover crops sunhemp (Crotalariajuncea, pigeon pea (Cajanus cajan (L. Millsp, velvet bean (Mucuna aterrima, sorghum (Sorgum technicum, and fallow on chemical attributes of soil cultivated with organic common bean and corn, under no-tillage (NT and conventional tillage (CT systems. The work was conducted in Santo Antônio de Goiás-GO, in Oxisol, in a randomized block design, with four replications. In November 2003 four experiments were installed, two of them under NT and the other two in CT. In each soil management system, an experiment was carried out with common bean crop and another with corn. Samples

  17. Adubação nitrogenada em cobertura na cultura do trigo em sistema de plantio direto após diferentes culturas Nitrogen fertilization of wheat grown under no-tillage after different cover crops

    Directory of Open Access Journals (Sweden)

    Antônio Joaquim Braga Pereira Braz

    2006-04-01

    Full Text Available Avaliou-se o comportamento do trigo irrigado, cultivado em sistema de plantio direto em sucessão a diferentes culturas de cobertura, em relação a adubação nitrogenada em cobertura. O experimento foi conduzido na Embrapa Arroz e Feijão, no município de Santo Antônio de Goiás, GO, em Latossolo Vermelho distrófico. Os tratamentos aplicados às parcelas do experimento foram constituídos pelas seguintes culturas plantas de cobertura: braquiária, milho em consórcio com braquiária, guandu, milheto, mombaça, sorgo granífero e estilosantes. Sobre as palhadas das culturas, após picadas, foi semeado o trigo para estudar a sua resposta à adubação nitrogenada em cobertura. Foram utilizadas quatro doses de nitrogênio em cobertura: 0, 30, 60 e 120 kg ha-1, usando como fonte a uréia.O rendimento de grãos do trigo após o cultivo de milho em consórcio com braquiária, guandu, sorgo e estilosantes obedeceu a uma função quadrática em resposta a adubação nitrogenada e após de braquiária e milheto a resposta foi linear. Não houve resposta na produtividade do trigo cultivado sobre mombaça à adubação nitrogenada em cobertura. As maiores produtividades do trigo em resposta à adubação nitrogenada em cobertura foram obtidas quando o mesmo foi cultivado em sucessão às gramíneas sorgo e braquiária.The performance of irrigated wheat grown under no-tillage in succession to different cover crops were evaluated in relation to nitrogen topdressing fertilization. The experiment was carried out at Embrapa Rice & Beans, in the municipality of Santo Antônio de Goiás, GO, on a Dystrophic Red Latosol. The treatments applied to the main plots were seven cover crops: (Brachiaria brizantha (Hochst. ex. A. Rich. Stapf. cv. Marandu; B.brizantha associated with corn (Zea mays L.; pigeon pea (Cajanus cajan (L. Millisp; millet (Pennisetum glaucum (L. R. Br.; Panicum maximum (Jacq. cv. Mombaça; sorghum (Sorghum bicolor (L. Moench; and

  18. Molecular characterisation and infectivity of a "Legumovirus" (genus Begomovirus: family Geminiviridae) infecting the leguminous weed Rhynchosia minima in Pakistan.

    Science.gov (United States)

    Ilyas, Muhammad; Qazi, Javaria; Mansoor, Shahid; Briddon, Rob W

    2009-11-01

    The legume yellow mosaic viruses (LYMVs) that cause extensive losses to grain legumes across southern Asia are an evolutionarily unusual group of begomoviruses (genus Begomovirus; family Geminiviridae) with bipartite genomes. All previously identified LYMVs were isolated from leguminous crop species. Here we have identified a virus related to the LYMVs in a common weed, the legume Rhynchosia minima originating from Pakistan. Analysis of the sequence of the virus shows it to be a typical bipartite begomovirus. Sequence comparisons to all other begomovirus sequences available in the databases show the virus from R. minima to be distinct, with the highest level of sequence identity (69.5%) to an isolate of Mungbean yellow mosaic virus. This indicates that the virus identified here is a new species in the genus Begomovirus for which we propose the name Rhynchosia yellow mosaic virus (RhYMV). By Agrobacterium-mediated inoculation we show that, in common with the other LYMVs, the clones of RhYMV are not infectious to the experimental host Nicotiana benthamiana. In soybean, the results of inoculation depended upon the variety. In soybean var. Ig6 the symptoms were mild and plants recovered from infection. However, in var. FS-85, symptoms were severe and progressed to necrosis, indicative of a hypersensitive response. These results indicate that there is resistance to RhYMV in the soybean germplasm. The significance of these results is discussed.

  19. Dinâmica do potássio nos resíduos vegetais de plantas de cobertura no Cerrado Potassium dynamics in crop residues of cover plants in Cerrado

    Directory of Open Access Journals (Sweden)

    José Luiz Rodrigues Torres

    2008-08-01

    Full Text Available A produção de biomassa, a manutenção dos resíduos vegetais sobre o solo e sua posterior decomposição são fatores de grande importância no estudo da ciclagem de nutrientes. Este estudo foi desenvolvido na área experimental do CEFET-Uberaba-MG, onde foram avaliados oito tipos de coberturas vegetais: milheto (Pennisetum americanum sin. tiphoydes, braquiária (Brachiaria brizantha, sorgo-forrageiro (Sorghum bicolor L. Moench, guandu (Cajanus cajan (L. Mill sp., crotalária (Crotalarea juncea, aveia-preta (Avena strigosa Schreb, pousio e área em preparo convencional de solo (testemunha em área de Cerrado, na região do Triângulo Mineiro. Avaliaram-se a fitomassa seca (FS, a decomposição dos resíduos em bolsas de decomposição, e a liberação de K. Utilizou-se um modelo matemático para descrever a decomposição dos resíduos e a liberação de K, e calcularam-se a constante de decomposição (k e o tempo de meia-vida (T½. O milheto, o sorgo e a crotalária foram as coberturas que apresentaram maiores produções de matéria seca. O maior acúmulo de K ocorreu em gramíneas e a maior liberação de K ocorreu no milheto, aveia, braquiária e crotalária nos primeiros 42 dias após manejo, nos dois períodos avaliados. A braquiária apresentou o menor T½ vida e a maior taxa de liberação de K.Crop residue production, plant residue maintenance and their decomposition are important factors in the understanding of nutrient recycling process. To evaluate K accumulation and release a study with eight cover crops types was developed: pearl millet (Pennisetum americanum sin. tiphoydes, brachiaria grass (Brachiaria brizantha, sorghum (Sorghum bicolor L. Moench, pigeonpea (Cajanus cajan (L. Millsp, sunn hemp (Crotalarea juncea and black oats (Avena strigosa Schreb, fallow land and conventional culture (control in the experimental area of CEFET-Uberaba-MG, in a Cerrado area. The dry mass production, crop residue decomposition in litter bags

  20. How effective are slurry storage, cover or catch crops, woodland creation, controlled trafficking or break-up of compacted layers, and buffer strips as on-farm mitigation measures for delivering an improved water environment?

    Directory of Open Access Journals (Sweden)

    Randall Nicola P

    2012-10-01

    Full Text Available Abstract Background Agriculture has intensified over the last 50 years resulting in increased usage of fertilizers and agrochemicals, changes in cropping practices, land drainage and increased stocking rates. In Europe, this has resulted in declines in the quality of soils and waters due to increased run off and water pollution. Fifty percent of nitrates in European rivers are derived from agricultural sources in the UK this value is as high as 70%, where agriculture also contributes to approximately 28% of phosphates and 76% of sediments recorded in rivers. Catchments dominated by agricultural land use have increased levels of pesticides and bacterial pathogens. European member states have a policy commitment to tackle water pollution through the Water Framework Directive. An analysis of the effectiveness of water pollution mitigation measures should enable decision makers and delivery agencies to better facilitate catchment planning. The aim of this systematic review is to assess the effectiveness of slurry storage, cover/catch crops, woodland creation, controlled trafficking/break-up of compacted layers and buffer strips, as on farm mitigation measures, for delivering an improved water environment. Methods The systematic review will consist of a searchable systematic map database for all the named interventions. Where possible, quantitative analysis will be used to assess the effectiveness of interventions. Electronic databases, the internet, and organisational websites will be searched, and stakeholders will be contacted for studies that investigate the impact of the on-farm mitigation measures on water quality. All studies found will be assessed for suitability for inclusion in the next stage. Inclusion criteria will be based on subject, intervention, comparator and outcome. The details of included studies will be incorporated into the systematic map database, and studies scored for effectiveness of intervention and study design. Where

  1. Legumin allergens from peanuts and soybeans: Effects of denaturation and aggregation on allergenicity

    NARCIS (Netherlands)

    Boxtel, E.L. van; Broek, L.A.M. van den; Koppelman, S.J.; Gruppen, H.

    2008-01-01

    Legumin proteins Ara h 3 from peanuts and glycinin from soybeans are increasingly described as important allergens. The stability of an allergen's IgE binding capacity towards heating and digestion is considered an important characteristic for food allergens. We investigated the effects of heating

  2. Potential values of some non-leguminous browse plants as dry ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-05-03

    May 3, 2010 ... plants as dry season feed for ruminants in Nigeria. D. O. Ogunbosoye* and O. J. Babayemi ... Inadequate feed supply is a major constraint to ruminant production during the dry season in the tropics. ... nutritional composition of some non leguminous multi- purpose trees by their chemical composition and in ...

  3. The active role of leguminous plant components in type 2 diabetes.

    Science.gov (United States)

    Gętek, Monika; Czech, Natalia; Muc-Wierzgoń, Małgorzata; Grochowska-Niedworok, Elżbieta; Kokot, Teresa; Nowakowska-Zajdel, Ewa

    2014-01-01

    Diabetes appears to be one of the most frequent noncommunicable diseases in the world. A permanent growth in the incidence of diabetes can be observed and according to the International Diabetes Federation (IDF) the year 2030 will mark the increase in the number of diabetics to 439 mln worldwide. Type 2 diabetes accounts for about 90% of all diabetes incidence. Nutrition model modification not only features the basic element in type 2 diabetes treatment but also constitutes the fundamental factor influencing a morbidity rate decrease. Leguminous plants are a key factor in the diabetic diet; plants such as pulses or soybeans are nutritious products valued highly in nutrition. These legumes are high in the content of wholesome protein and contain large amounts of soluble alimentary fiber fractions, polyunsaturated fatty acids, vitamins and minerals, and bioactive substances with antioxidant, anti-inflammatory, and anticancer activity. They are distinguished by the high amount of bioactive compounds that may interfere with the metabolism of glucose. The most significant bioactive compounds displaying antidiabetic activity in leguminous plants are as follows: genistein and daidzein, alpha-amylase inhibitors, and alpha-glucosidase inhibitors. In vitro research using leguminous plant extracts has confirmed their antidiabetic properties. Leguminous plants should be employed in the promotion of healthy lifestyles in terms of functional food.

  4. Potential N2O emissions from leguminous tree plantation soils in the humid tropics

    Science.gov (United States)

    Arai, Seiko; Ishizuka, Shigehiro; Ohta, Seiichi; Ansori, Saifuddin; Tokuchi, Naoko; Tanaka, Nagaharu; Hardjono, Arisman

    2008-06-01

    We compared nitrous oxide (N2O) emissions over 1 year from soils of plantations growing acacia, which is a leguminous plant capable of symbiotic nitrogen fixation in root nodules, and secondary forests in Sumatra, Indonesia. N2O emissions from acacia plantation soils fluctuated seasonally, from high in the wetter season to low in the drier season, whereas N2O emissions from secondary forest soils were low throughout the year. Water-filled-pore-space data showed that denitrification contributed substantially to N2O emissions from soils at acacia sites. The average annual N2O flux in acacia plantations was 2.56 kg N ha-1 a-1, which was eight times higher than that from secondary forest soils (0.33 kg N ha-1 a-1). In secondary forests, NH4+ was the dominant form of inorganic nitrogen. However, in acacia plantations, the NH4+: NO3- ratio was relatively lower than that in secondary forests. These results suggest that secondary forests were nitrogen limited, but acacia plantations were less nitrogen limited. Leguminous tree plantations may increase nitrogen cycling, resulting in greater N2O emissions from the soil. However, on a global warming potential basis, N2O emissions from acacia plantation soils accounted for less than 10% of the carbon uptake by plants. Nevertheless, because of the spread of leguminous tree plantations in Asia, the importance of N2O emissions from leguminous tree stands will increase in the coming decades.

  5. Changes to soil organic N dynamics with leguminous woody plant encroachment into grasslands

    Science.gov (United States)

    The encroachment of nitrogen-fixing trees and shrubs into grasslands and savannas occurs worldwide. In the Rio Grande Plains region of southern Texas, previous studies have shown that woody encroachment by leguminous Prosopis glandulosa (mesquite) trees increases soil and microbial biomass nitrogen ...

  6. The Active Role of Leguminous Plant Components in Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Monika Gętek

    2014-01-01

    Full Text Available Diabetes appears to be one of the most frequent noncommunicable diseases in the world. A permanent growth in the incidence of diabetes can be observed and according to the International Diabetes Federation (IDF the year 2030 will mark the increase in the number of diabetics to 439 mln worldwide. Type 2 diabetes accounts for about 90% of all diabetes incidence. Nutrition model modification not only features the basic element in type 2 diabetes treatment but also constitutes the fundamental factor influencing a morbidity rate decrease. Leguminous plants are a key factor in the diabetic diet; plants such as pulses or soybeans are nutritious products valued highly in nutrition. These legumes are high in the content of wholesome protein and contain large amounts of soluble alimentary fiber fractions, polyunsaturated fatty acids, vitamins and minerals, and bioactive substances with antioxidant, anti-inflammatory, and anticancer activity. They are distinguished by the high amount of bioactive compounds that may interfere with the metabolism of glucose. The most significant bioactive compounds displaying antidiabetic activity in leguminous plants are as follows: genistein and daidzein, alpha-amylase inhibitors, and alpha-glucosidase inhibitors. In vitro research using leguminous plant extracts has confirmed their antidiabetic properties. Leguminous plants should be employed in the promotion of healthy lifestyles in terms of functional food.

  7. Desenvolvimento de plantas de cobertura e produtividade da soja conforme atributos físicos em solo compactado Growth of cover crops and soybean yield according to physical attributes in compacted soil

    Directory of Open Access Journals (Sweden)

    Romano R. Valicheski

    2012-09-01

    Full Text Available Com a intensa utilização de tecnologias voltadas à mecanização das operações agrícolas, a compactação do solo é um fator que tem limitado a produtividade. Para atenuar este problema, o uso de plantas de cobertura do solo é frequentemente recomendado. Com o objetivo de avaliar o efeito da compactação nas propriedades físicas do solo, no desenvolvimento de plantas de cobertura e na produtividade da soja, conduziu-se um experimento no delineamento em blocos casualizados no esquema fatorial 2 x 5, sendo duas espécies de plantas de cobertura (aveia preta - Avena strigosa e nabo forrageiro - Raphanus sativus e cinco níveis de compactação (0, 2, 4, 6 e 8 passadas de trator com 5,0 Mg na superfície do solo, com quatro repetições. Intensidades de tráfego superiores a 2 passadas de trator alteram a densidade do solo, a porosidade total e a resistência mecânica à penetração, na camada de 0-0,10 m, e reduzem, de forma linear, a altura e a produção de matéria seca da parte aérea das plantas de cobertura. O cultivo da aveia preta ou nabo forrageiro antecedendo a soja, associado ao uso de sulcadores na operação de semeadura da soja minimiza os efeitos da compactação do solo, possibilitando obter-se produtividades superiores a 3,5 t ha-1.With the intense use of technologies geared toward the mechanization of agricultural operations, soil compaction is a factor limiting productivity. To mitigate this problem, the use of ground cover crops is frequently recommended. With the objective to determine the effect of compaction on the soil physical properties, an experiment was carried out using randomized block design in a 2 x 5 factorial scheme. Two cover crop species (black oat - Avena strigosa and forage radish - Raphanus sativus, five levels of compaction (0, 2, 4, 6 and 8 tractor passes with 5.0 Mg on the soil surface, with four repetitions were studied. Traffic intensities greater than 2 tractor passes change soil density

  8. Cultivos de cobertura: efectos sobre la macroporosidad y la estabilidad estructural de un suelo franco-limoso Cover crops: effects on soil macroporosity and soil structural stability in a silt loam soil

    Directory of Open Access Journals (Sweden)

    María Florencia Varela

    2011-07-01

    Full Text Available Los suelos franco-limosos manejados con siembra directa a menudo poseen porosidad estructural baja e inestable. Con el objetivo de determinar la capacidad de los cultivos de cobertura (CC de mejorar la porosidad y estabilidad estructural de estos suelos se llevaron a cabo experimentos de campo y de invernáculo. Ambos tuvieron tratamientos con y sin CC (avena, Avena sativa L., en rotación con soja (Glicine max L. Merr.. Luego de los CC se midieron densidad aparente (DA, el índice de inestabilidad estructural (IE y en el ensayo de invernáculo además, se midió la evolución de la distribución de tamaño de poros (DTP. En ambos ensayos la introducción de CC no disminuyó la DA, aunque incrementó la estabilidad del suelo (PNo- till (NT silt loam topsoils have often a low and unstable structural porosity. The objective of this study was to determine the capability of cover crops (CC of improving the structural porosity and stability of silt loam soils under NT. Greenhouse and field experiments were carried out on a silt loam soil (Typic Argiudoll with and without CC (oat, Avena sativa L. in crop sequences with soybean (Glicine max L. Merr.. Soil bulk density (DA and aggregate instability index (IE were measured after the CC in both experiments. In the greenhouse experiment, soil pore size distribution (DTP was measured. The use of CC did not change DA, but soil IE was significantly lower in crop sequences with CC (P < 0.05 both under field and greenhouse conditions. Stability increases were likely due to the effect of CC residues and root mass. No differences in DTP were found between treatments, although a significant effect of sampling date was observed (P<0.05. Changes in DTP were due to significant increases in mesopore (517.5% and macropore (52.7% volumes. Such changes occurred in all the treatments, probably due to the soil wetting-drying cycles. The results found in this study agree with other studies carried out on silt loams in the

  9. Fósforo no solo e desenvolvimento de soja influenciados pela adubação fosfatada e cobertura vegetal Phosphorus in soil and soybean growth as affected by phosphate fertilization and cover crop residues

    Directory of Open Access Journals (Sweden)

    Juliano Corulli Corrêa

    2004-12-01

    Full Text Available A eficiência agronômica dos adubos fosfatados pode ser afetada pelas fontes de fosfato, propriedades do solo, modos de aplicação e espécies vegetais. O objetivo deste trabalho foi avaliar o efeito de doses de fósforo e resíduos de plantas de cobertura na dinâmica do fósforo no solo e no desenvolvimento inicial da soja. O experimento foi realizado em casa de vegetação, em vasos com material de um Latossolo Vermelho distrófico. Os tratamentos constituíram-se de três palhadas, milheto, aveia e sorgo-de-guiné, simulando a cobertura do solo, na quantidade de 8 t ha-1 de massa de matéria seca, interagindo com 0, 50, 100 e 150 kg ha-1 de P, aplicados sobre a palhada, na forma de superfosfato simples. As doses de P e os diferentes tipos de palha influenciaram a dinâmica do P no solo. A cobertura com milheto foi mais eficiente na lixiviação do P disponível, enquanto as coberturas com aveia e sorgo-de-guiné foram mais eficientes em lixiviar o P orgânico.The efficiency of phosphate fertilizers can be affected by phosphate sources, soil properties, way of application and plant species. The objective of this work was to evaluate the effect of phosphorus levels and cover crops residues on phosphorus dynamics in the soil and soybean initial growth. The experiment was carried out in a greenhouse in pots containing a dystrophic Red Latosol (Typic Hapludox. The treatments consisted of three cover crop residues: pear millet (Penisetum americanum L., oats (Avena strigosa and guinea sorghum (Sorghum bicolor at 8 t ha-1, interacting with 0, 50, 100 and 150 kg ha-1 of P , applied over straw mulch, as simple superphosphate. Phosphorus levels and the different residues affected P transport through the soil. Pear millet was more efficient in leaching available P while oats and guinea sorghum were more effective in leaching organic phosphorus.

  10. Caracterização das perdas e distribuição de cobertura vegetal em colheita mecanizada de soja Characterization of losses and crop residue cover distribution in soybean mechanized harvest

    Directory of Open Access Journals (Sweden)

    Anderson de Toledo

    2008-12-01

    Full Text Available O conceito de controle de qualidade nas operações inserido na agricultura é viabilizado por incidir diretamente nos principais objetivos do processo produtivo: retorno econômico e aumento da produtividade. A colheita mecanizada normalmente é realizada sem que haja controle efetivo para que a variabilidade das perdas fique dentro de padrões aceitáveis. Esta pesquisa teve o objetivo de determinar e caracterizar as perdas e a distribuição da cobertura vegetal após a colheita mecanizada da soja, por meio de ferramenta de controle estatístico de processo (cartas de controle. A média da perda de grãos total foi próxima do limite superior aceitável para a cultura da soja, apresentando alta variabilidade entre os pontos, tornando o processo fora de controle. A distribuição de cobertura vegetal manteve-se em processo controlado, com maior variabilidade onde o relevo foi mais inclinado. A utilização das cartas de controle foi eficiente na identificação dos pontos fora de controle e na avaliação da qualidade do processo de colheita.The concept of operation control inserted in agriculture is made possible by making a directly influence in the main objectives of productive process, economic return and increase of productivity. The mechanized harvest normally is carried out without an effective control of the variability of losses so that it maintains acceptable standards. This research aimed to determinate and characterize the losses and crop residue cover distribution after soybean mechanized harvest, using the tool of statistical process control (control charts. The average of total grain losses was near the upper limit specified for losses in soybean, showing high variation between points, and putting the process out of control. The residue crop cover distribution stayed under control process, with greater variability where the terrain was more sloping. The use of control charts was efficient to identify the points out of control

  11. Cover crop management in the weed control and productive performance in cornManejo de plantas de cobertura no controle de plantas daninhas e desempenho produtivo da cultura do milho

    Directory of Open Access Journals (Sweden)

    Pedro Valério Dutra de Moraes

    2013-05-01

    Full Text Available Objetivou-se avaliar espécies vegetais com potencial alelopático, associados às práticas de manejo e ao uso de herbicida nicosulfuron, no controle de plantas daninhas e nos componentes de produtividade da cultura do milho. O delineamento experimental utilizado foi em blocos ao acaso, com quatro repetições. O experimento foi composto por três fatores: espécies de cobertura, manejo das coberturas e aplicação ou não de herbicida nicosulfuron em pós-emergência. As variáveis avaliadas foram: número de plantas daninhas, número de fileiras de grãos, número de grãos por fileira, número de grãos por espiga e produtividade de grãos de milho. A cobertura de azevém, em geral, reduz o número de plantas daninhas emergidas e favorece o desempenho produtivo do milho. O manejo das plantas de cobertura com roçada e retirada da palha reduz a produtividade do milho. A maior produtividade do milho, foi observada com a aplicação de nicosulfuron em pós-emergência, independente da cultura de cobertura ou do manejo adotado. The objective of the study was evaluate the allelopathy of cover species, associated to management practices and use of nicosulfuron herbicide on the productive performance of corn. The experimental design consisted of complete randomized block with four replications. The treatments were: cover species, cover management and application or not of post-emergence herbicide. The variables evaluated were: number of weeds, number of rows kernels, number of kernels rows, number of kernels ear and grain yield of corn. Lolium multiflorum, reduced the number of emerged weeds and provides the best results in productive performance. The management simulated grazing, does not favor the yield of corn. The application of nicosulfuron in post-emergence, along with the allelopathic activity increases the productive performance of corn, regardless of cover crop or soil management.

  12. Crops, Nitrogen, Water: Are Legumes Friend, Foe, or Misunderstood Ally?

    Science.gov (United States)

    Adams, Mark A; Buchmann, Nina; Sprent, Janet; Buckley, Thomas N; Turnbull, Tarryn L

    2018-03-17

    Biological nitrogen fixation (BNF) by crop legumes reduces demand for industrial nitrogen fixation (INF). Nonetheless, rates of BNF in agriculture remain low, with strong negative feedback to BNF from reactive soil nitrogen (N) and drought. We show that breeding for yield has resulted in strong relationships between photosynthesis and leaf N in non-leguminous crops, whereas grain legumes show strong relations between leaf N and water use efficiency (WUE). We contrast these understandings with other studies that draw attention to the water costs of grain legume crops, and their potential for polluting the biosphere with N. We propose that breeding grain legumes for reduced stomatal conductance can increase WUE without compromising production or BNF. Legume crops remain a better bet than relying on INF. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Macrofauna edáfica associada a plantas de cobertura em plantio direto em um Latossolo Vermelho do Cerrado Soil macrofauna communities and cover crops in a Cerrado Oxisol under no tillage

    Directory of Open Access Journals (Sweden)

    Glenio Guimarães Santos

    2008-01-01

    Full Text Available O objetivo deste trabalho foi caracterizar a macrofauna edáfica e avaliar o efeito de plantas de cobertura em plantio direto, nos principais grupos da macrofauna do solo, em duas épocas de avaliação em um Latossolo Vermelho distroférrico. O delineamento experimental foi o de blocos ao acaso, com oito tratamentos (plantas de cobertura e quatro repetições. As plantas de cobertura: Crotalaria juncea, guandu-anão (Cajanus cajan, Stylosanthes guianensis, Brachiaria brizantha, B. brizantha consorciada com milho (Zea mays, milheto (Pennisetum glaucum, mombaça (Panicum maximum e Sorghum bicolor foram cultivadas de novembro a abril. Em setembro de cada ano, foi realizado o plantio de feijão, em cultivo irrigado por pivô central. A área útil em cada parcela foi de 60 m². Amostras de solo na forma de monólitos (25x25 cm foram retiradas aleatoriamente em cada parcela, para contagem da macrofauna, às profundidades de 0-10 cm e 10-20 cm, em abril e em setembro de 2005. Os grupos taxonômicos, identificados em ordem decrescente de densidade relativa, são: Formicidae, Oligochaeta, Dermaptera, Coleoptera, Hemiptera, Miriapoda, Isoptera, Araneae, Lepidoptera, Blattodea e larvas de Diptera. Crotalaria juncea apresentou maior densidade de macrofauna, seguida por B. Brizantha, B. Brizantha consorciada com milho, Sorghum bicolor, Stylosanthes guianensis, Cajanus Cajans, Pennisetum Glaucum e Panicum maximum. O uso das plantas de cobertura, associado à irrigação na avaliação de setembro, favorece a colonização do solo pela macrofauna.The objective of this work was to characterize soil fauna groups and to evaluate the effects of cover crops under no-tillage system, in a Cerrado Oxisol, in two evaluation periods. The cover crops: Crotalaria juncea, Cajanus cajan, Stylosanthes guianensis, Brachiaria brizantha, Brachiaria brizantha/ Zea mays association, Pennisetum glaucum, Panicum maximum and Sorghum bicolor were cultivated from November to April

  14. Manejo de nitrogênio no milho sob plantio direto com diferentes plantas de cobertura, em Latossolo Vermelho Nitrogen management in corn under no-tillage with different cover crops in a Rhodic Hapludox soil

    Directory of Open Access Journals (Sweden)

    Edson Cabral da Silva

    2006-03-01

    Full Text Available O objetivo deste trabalho foi definir a melhor dose e época de aplicação, e a eficiência de utilização do N, utilizando-se uréia marcada com 15N, pelo milho cultivado sob plantio direto, em sucessão à crotalária (Crotalaria juncea, ao milheto (Pennisetum americanum e à vegetação espontânea (pousio, em um Latossolo Vermelho no Cerrado. O delineamento experimental foi o de blocos ao acaso, com 24 tratamentos e quatro repetições, em esquema fatorial incompleto, 3x3x2 + 6: três doses de N (80, 130 e 180 kg ha-1; três sistemas de cobertura do solo (crotalária, milheto e pousio; duas épocas de aplicação do N (estádio quatro ou oito folhas; e seis tratamentos adicionais (três sem aplicação de N e três que receberam 30 kg ha-1 de N na semeadura. O cultivo do milho em sucessão à crotalária proporciona maior quantidade na planta e aproveitamento pela planta do N proveniente do fertilizante e maior produtividade de grãos. A aplicação do N ao milho com quatro folhas proporciona maior produtividade de grãos, comparada à aplicação com oito folhas, quando em sucessão ao milheto.The objective of this work was to evaluate the best rate and time for N application, and N utilization using urea-15N, by corn crop grown under no-tillage system, in succession to sun hemp (Crotalaria juncea L., millet (Pennisetum americanum and to the spontaneous vegetation (fallow ground, in a Rhodic Hapludox soil in Cerrrado. The experimental design was randomized complete blocks, with 24 treatments and four replications, in an incomplete factorial 3x3x2 + 6: three N rates (80, 130 and 180 kg ha-1 N; three preceding cover crops (sun hemp, millet and fallow ground; two N application time (four leaves or eight leaves stage; and six additional treatments (three without N application and three that received 30 kg ha-1 N at seeding. The corn grown in succession to sun hemp provided higher amount of N derived from fertilizer, N utilization efficiency

  15. Leguminous species sequester more carbon than gramineous species in cultivated grasslands of a semi-arid area

    Science.gov (United States)

    Liu, Yu; Tian, Fuping; Jia, Pengyan; Zhang, Jingge; Hou, Fujiang; Wu, Gaolin

    2017-01-01

    The establishment of grasslands on abandoned cropland has been proposed as an effective method to mitigate climate change. In this study, five cultivated grasslands (three leguminous species and two gramineous species), one abandoned cropland, and one natural grassland were studied to examine how soil organic carbon (SOC) sequestration rate and sequestration efficiency change in a semi-arid area in China. Our results showed that leguminous grasslands had greater total biomass (above- and belowground biomass), SOC storage, SOC sequestration rate, and efficiency than gramineous grasslands, abandoned cropland, and natural grassland during the experimental period. The largest soil carbon (C) accumulation in leguminous grassland was mainly attributed to the capacity to incorporate C and the higher biomass production. Leguminous grasslands accumulated more SOC than gramineous grasslands by 0.64 Mg C ha-1 yr-1. The average SOC sequestration efficiency in leguminous grassland (1.00) was about 2 times greater than gramineous grassland (0.34). The results indicate that cultivated leguminous grassland sequestered more SOC with higher SOC sequestration efficiency than cultivated gramineous grassland in arid and semi-arid areas. Our results provide a reference for ecological management in arid and semi-arid areas.

  16. ECONOMIC VALUE OF SOME LEGUMINOUS PLANT SPECIES OF THE COLLECTIONS FROM THE BOTANICAL GARDEN (INSTITUTE OF THE ACADEMY OF SCIENCES OF MOLDOVA

    Directory of Open Access Journals (Sweden)

    Alexandru TELEUTA

    2016-12-01

    Full Text Available The results of the evaluation of the growth and development rates, the seed productivity, the green mass yield, the biochemical composition and the content of amino acids, phosphorous and calcium, the nutritive and energy value of the forage, as well as the biomethane productivity of local ecotypes of the leguminous species maintained in monoculture, in the collection of the Botanical Garden (Institute of the Academy of Sciences of Moldova (BG ASM: Astragalus ponticus, Coronilla varia, Lotus corniculatus, Medicago falcata, Onobrychis arenaria and Trifolium repens are presented in this article. Control variants – the traditional forage crops: Medicago sativa and Onobrychis viciifolia. The local ecotypes of the studied leguminous species were characterized by different growth and development rates. Coronilla varia and Lotus corniculatus, in the 2nd-3rd years, could be harvested, for the first time, 5 days earlier than Medicago sativa, but Medicago falcata and Onobrychis viciifolia – 18 days later. The green mass yield varied from 0.83 kg/m2 to 4.08 kg/m2. The studied ecotypes reached amounts of 0.60-0.89 nutritive units/kg and metabolizable energy 8.05-9.90 MJ/kg of dry matter, the content of digestible protein, of 106.28-225.09 g/nutritive unit, met the zootechnical standards; seed production: 19.12-83.00 g/m2; the biomethane yield ranged from 692 to 3197 m3/ha. Higher yield of natural forage, dry matter and biomethane was produced by Onobrychis arenaria and Coronilla varia.

  17. Ecological effects of matching between mycorrhizal fungus and leguminous plants in solid wastes of mine area

    Energy Technology Data Exchange (ETDEWEB)

    Bi Yin-li; Wu Fu-yong; Quan Wen-zhi [China University of Mining & Technology, Beijing (China). School of Resources and Safety Engineering

    2006-05-15

    The matching relations between two kinds of AM fungus and three kinds of leguminous plants including white clover, alfaifa and acacia was studied based on two special kinds of solid waste (coal gangue and fly ash) in mine area. G. mosseae fungi were screened out as superiority fungi taken the biomass, phosphorus adsorption efficiency, the infection rate and the mycorrhizal dependency of host plant as the criterion. The results show that: the two optimal combinations of AM fungi and leguminous plant were formed, one was G. mosseae and alfalfa in fly ash and the mixture of coal gangue and fly ash, the other was G. geosporum and acacia in the mixture of coal gangue and sand; the growth and absorbing ability to phosphorus of plants were improved; and the dependences between mycorrhizal fungus and plants and the infectivity of mycorrhizal were better. The good ecological effects was obtained. 18 refs., 7 tabs.

  18. Ana o 2, a major cashew (Anacardium occidentale L.) nut allergen of the legumin family.

    Science.gov (United States)

    Wang, Fang; Robotham, Jason M; Teuber, Suzanne S; Sathe, Shridhar K; Roux, Kenneth H

    2003-09-01

    We recently cloned and described a vicilin and showed it to be a major cashew allergen. Additional IgE-reactive cashew peptides of the legumin group and 2S albumin families have also been reported. Here, we attempt to clone, express and characterize a second major cashew allergen. A cashew cDNA library was screened with human IgE and rabbit IgG anti-cashew extract antisera, and a reactive nonvicilin clone was sequenced and expressed as a fusion protein in Escherichia coli. Immunoblotting was used to screen for reactivity with patients' sera, and inhibition of immunoblotting was used to identify the corresponding native peptides in cashew nut extract. The identified allergen was subjected to linear epitope mapping using SPOTs solid-phase synthetic peptide technology. Sequence analysis showed the selected clone, designated Ana o 2, to encode for a member of the legumin family (an 11S globulin) of seed storage proteins. By IgE immunoblotting, 13 of 21 sera (62%) from cashew-allergic patients were reactive. Immunoblot inhibition data showed that the native Ana o 2 constitutes a major band at approximately 33 kD and a minor band at approximately 53 kD. Probing of overlapping synthetic peptides with pooled human cashew-allergic sera identified 22 reactive peptides, 7 of which gave strong signals. Several Ana o 2 epitopes were shown to overlap those of the peanut legumin group allergen, Ara h 3, in position but with little sequence similarity. Greater positional overlap and identity was observed between Ana o 2 and soybean glycinin epitopes. We conclude that this legumin-like protein is a major allergen in cashew nut. Copyright 2003 S. Karger AG, Basel

  19. Mimosine, the Allelochemical from the Leguminous Tree Leucaena leucocephala, Selectively Enhances Cell Proliferation in Dinoflagellates

    Science.gov (United States)

    Yeung, Patrick K. K.; Wong, Francis T. W.; Wong, Joseph T. Y.

    2002-01-01

    Mimosine, the allelochemical from the leguminous tree Leucaena leucocephala, is toxic to most terrestrial animals and plants. We report here that while mimosine inhibits major phytoplankton groups, it enhances cell proliferation in dinoflagellates. On addition to coastal seawater samples, mimosine is able to confer a growth advantage to dinoflagellates. The use of mimosine will promote the isolation and culture of this group of phytoplankton. PMID:12324368

  20. Cultivo orgânico sequencial de hortaliças com dois sistemas de irrigação e duas coberturas de solo Successive organic cultivation of vegetable crops in two irrigation systems and two soil covers

    Directory of Open Access Journals (Sweden)

    Roberto BF Branco

    2010-03-01

    replications, resulting in 24 experimental units. The following treatments were assessed: a two irrigation systems, sprinkle and drip, b two soil covers, plastic and straw of sugar cane and c two hybrids or cultivars. Two different cropping sequences were carried out: (1 iceberg lettuce - tomato - broccoli and; (2 crisp lettuce - snap beans - cabbage. The agronomic characteristics of each species were evaluated. In sequence 1, iceberg lettuce growth performed better when irrigated by the drip system, but there was no difference between the soil covers and 'Rubette' presented higher yield. Higher tomato yields were observed in "mulching"plastic regardless the irrigation system and broccoli was unaffected by treatments. In sequence 2, crisp lettuce and snap beans were more productive when irrigated by drip and grown on plastic covering. Cabbage performed better with plastic film covering soil surface.

  1. Soil macrofauna in cover crops of figs grown under organic management Macrofauna edáfica sob coberturas do solo no cultivo de figo sob manejo orgânico

    Directory of Open Access Journals (Sweden)

    Analy de Oliveira Merlim

    2005-01-01

    Full Text Available Soil fauna plays an important role in organic management through their effects on soil organic decomposition, nutrient mineralization, and amelioration of the soil's physical properties. This work evaluates the density and diversity of the soil macrofauna under types of cover plants in areas cultivated with Ficus carica L. under organic management. The soil macrofauna was collected in 0.25 × 0.25 m areas, down to a soil depth of 0.3 m, and at the surface layer. The treatments consisted of bahiagrass living mulch (Paspalum notatum, siratro living mulch (Macroptilium atropurpureum, and bahiagrass mulch. The highest macrofauna density and the lowest diversity were observed in bahiagrass, of which 80% were represented by ants, thus characterizing the soil under this cover crop as showing the lowest functional diversity and quality.A fauna do solo tem papel importante em sistemas orgânicos, através dos seus efeitos na decomposição da matéria orgânica, mineralização de nutrientes e condicionamento físico do solo. Este trabalho avaliou a densidade e a diversidade da macrofauna edáfica sob tipos de cobertura do solo em áreas cultivadas com Ficus carica L. sob manejo orgânico do solo. A macrofauna foi coletada em áreas de 0,25 × 0,25 m e amostraram-se as camadas de material vegetal e solo até a profundidade de 0,3 m, nos meses de março e setembro de 2001. Os tratamentos constaram de cobertura viva com grama batatais (Paspalum notatum, cobertura viva de siratro (Macroptilium atropurpureum e cobertura morta formada por palha de grama batatais. A mais alta densidade da macrofauna e a mais baixa diversidade foi observada em grama batatais, sendo mais de 80% dessa fauna de formigas, o que caracteriza o solo sob influência desta cobertura como o de mais baixa diversidade funcional e qualidade, comparado às outras coberturas.

  2. Transformation of leguminous plants to study symbiotic interactions.

    Science.gov (United States)

    Iantcheva, Anelia; Mysore, Kirankumar S; Ratet, Pascal

    2013-01-01

    Legume plants are important in agriculture because they represent an important source of protein for human and animal consumption. This high protein content results from their capacity to use atmospheric nitrogen for their nutrition as a consequence of their symbiotic interaction with rhizobia. Understanding this interaction at the molecular level is a prerequisite for its better use in agriculture and for the long term objective of its transfer to other crops. Agrobacterium-mediated transformation is a tool of choice for studying this interaction and for unraveling the function of the different genes discovered through classical genetic approaches. However, legume plants are often recalcitrant to regeneration and transformation. This paper describes the technology developments (regeneration, transformation, insertion mutagenesis) related to Agrobacterium transformations that were established in the legume plants, as well as different examples of the technology developments or gene discoveries resulting from these studies.

  3. Cambios en las propiedades de un suelo franco bajó producción orgánica de manzano utilizando coberturas vegetales Changes in soil properties in a loamy soil under organic production of apples using cover crops

    Directory of Open Access Journals (Sweden)

    Martía Cristina Aruani

    2006-12-01

    tratamientos con coberturas perennes (A+F y Tr.Orchard floor management in the Rio Negro valley is based on continuous tillage which in the long term may negatively affect soil properties. Therefore, the aim of this research was to evaluate the effect of different soil management treatments in an organic apple orchard (Malus domestica Bork. cv. Royal Gala on nutrient availability, soil aggregates stability and organic carbon (CO and total nitrogen (Nt concentration in soil aggregates in a loamy soil. In March 1999, cover treatments applied to the inter-row spaces were: 1 permanent cover of fescue (Festuca arundinacea plus alfalfa (Medicago sativa (A+F; 2 permanent cover of strawberry clover (Trifolium fragiferum (Tr; 3 seeding of common vetch (Vicia sativa (V; and 4 control, natural soil vegetation and disking twice in late winter (T. In November 2002, soil samples were taken at three soil depths, 0-7.5; 7.5-15, and 15-30 cm to determine soil organic matter (OM, total nitrogen (Nt, available phosphorus (P and exchangeable bases (Ca+2, K+ and Mg+2. In the top 0-7.5 cm macro aggregate (100-2,000 µm micro aggregate (0-100 µm fractions and the content of OM, OC and Nt were determined. Organic matter and Nt concentration in the perennial cover crops treatments (A+F and Tr increased, and K+ were higher only in the 0-7.5 cm soil depths respect the V and T treatments. Magnesium concentration increased two-fold in the top 15 cm of soil in A+F compared to T. Calcium concentrations in A+F and Tr were higher than T at all soil depths and for the top 15 cm, respectively. In the T treatment macro-aggregates diminished and microaggregates increased due to soil cultivation compared to the perennial cover crops.

  4. Isolation and biochemical characterization of a novel leguminous defense peptide with antifungal and antiproliferative potency.

    Science.gov (United States)

    Wang, Shaoyun; Rao, Pingfan; Ye, Xiuyun

    2009-02-01

    Leguminous plants have formed a popular subject of research owing to the abundance of proteins and peptides with important biological activities that they produce. The antifungal proteins and peptides have been purified from a number of leguminous species. However, research continues to discover novel antifungal plant-produced peptides and proteins are being needed, specially those novel ones with both antifungal activity and other significant bioactivities. The objective of this study was to isolate a novel peptide from Phaseolus limensis. A 6.8 kDa peptide designated Limyin, with both antifungal and antiproliferative activity, was isolated from the large lima bean (P. limensis) legumes. The isolation procedure consisted of extraction, precipitation, affinity chromatography on Affi-gel blue gel, ion chromatography on SP-Toyopearl, and gel filtration on Superdex 75. Its N-terminal sequence was determined to be KTCENLATYYRGPCF, showing high homology to defensin and defensin precursors from plants. It potently suppressed mycelial growth in Alternaria alternata, Fusarium solani, and Botrytis cinerea. Its antifungal activity was stable up to 80 degrees C. It showed antiproliferative activity towards tumor cells including human liver hepatoma cells Bel-7402 and neuroblastoma cells SHSY5Y. However, it had no effect on bacteria Staphylococcus aureus and Salmonella. The present findings make a significant addition of the research on leguminous plants.

  5. Evaluation of natural 15N abundance method in estimating symbiotic dinitrogen fixation by leguminous grasses

    International Nuclear Information System (INIS)

    Yao Yunyin; Cheng Ming; Ma Changlin; Wang Zhidong; Hou Jinqin; Zhang Lihong; Luo Yongyun

    1991-01-01

    Natural 15 N abundance method was used to estimate contribution of symbiotic dinitrogen fixation by leguminous grasses. With the method the expensive 15 N fertilizer did not need to be applied to the soil and the normal ecosystem was not disturbed. Collecting samples of shoots of leguminous grasses and measuring the content of 15 N in them wee all to do for estimating potential of symbiotically fixed N 2 . Isotopic fractionation associated with N 2 fixation by legumes was studied. Values for 7 cultivars of alfalfa were ranged between 1.0000 ∼ 1.0015 (δ 15 N values were -0.05 ∼ 1.47 per mille); and the values for white clover, mung bean and whitepopinac lead tree were 0.0079, 0.9983 and 1.0018 (δ 15 N values: 2.15, 1.74 and -1.81 per mille) respectively. According to the δ 15 N values of grasses tested, the potential of N 2 fixation for 6 cultivars of alfalfa was estimated. Glory and rambler had higher potential of N 2 fixation; Baoding, Aigonquin and Minto had lower potential, and Peru was the lowest.N 2 fixing activity of alfalfa varied with different periods. The peak was found between June and July. Effects of non-N 2 -fixing references and different methods on estimates of %Ndfa of leguminous grasses were also discussed

  6. 76 FR 71271 - Common Crop Insurance Regulations; Fresh Market Tomato (Dollar Plan) Crop Provisions

    Science.gov (United States)

    2011-11-17

    ... policy does not cover the inability to market the insured crop due to quarantine, boycott, or refusal of... are unable to market the insured crop due to quarantine, boycott, or refusal of any person to accept...

  7. Calagem superficial e cobertura de aveia preta antecedendo os cultivos de milho e soja em sistema plantio direto Surface lime application and black oat cover preceding corn and soybean crops under a no-till system

    Directory of Open Access Journals (Sweden)

    Eduardo Fávero Caires

    2006-02-01

    rendimento de milho, mas não influiu no rendimento de soja, cultivada após o milho, no sistema plantio direto.Cover crop residues mobilize cations and benefit the action of lime applied on the soil surface owing to the release of low molecular weight organic acids from the soluble fraction of residues. However, these effects in no-till system are yet to be confirmed in field studies. A five-year trial was carried out on a no-till dystrophic Rhodic Hapludox in Ponta Grossa, State of Paraná, Brazil, with the aim of evaluating changes in chemical soil attributes, as well as the corn and soybean response to surface application of dolomitic lime (0, 2.5, 5.0 and 7.5 t ha-1, with and without black oat cover. Lime rates were applied onto the main plots in November 2000 and the treatments on the subplots consisted of the presence or absence of black oat in 2001 and 2002, preceding corn and soybean crops. Surface-applied lime did not influence the dry matter yield of black oat, which was approximately 4 t ha-1 in both 2001 and 2002 years. Liming did not affect the H+ ions neutralizing capacity (482 mmol c dm-3, the sum of soluble cations (29.5 mmol c L-1 or electric conductivity (1,230 µS cm-1 of the black oat extract either. Liming applied on the soil surface decreased exchangeable Al3+ and increased pH, exchangeable Ca2+ and exchangeable Mg2+ down to a 10 cm depth. Black oat residue on the soil surface under no-till did not benefit the mobility of surface-applied lime to alleviate subsoil acidity. Surface application of lime did not affect corn mineral nutrition or corn and soybean yields, but decreased Zn and Mn concentrations in soybean leaves. Cover black oat residue raised the P, Ca, and Mg concentrations in the corn and N and P in the soybean leaves and caused a decrease of Mn concentration in the soybean leaves. The black oat cover on the soil surface increased corn yield, but did not affect soybean yield, grown under no-till after corn.

  8. Land Cover

    Data.gov (United States)

    Kansas Data Access and Support Center — The Land Cover database depicts 10 general land cover classes for the State of Kansas. The database was compiled from a digital classification of Landsat Thematic...

  9. Soil cover and wind erosion

    Energy Technology Data Exchange (ETDEWEB)

    Fryrear, D.W.

    Wind erosion on agricultural lands can be reduced if the soil surface is protected with crop residues. In evaluating the influence of residues on wind erosion, previous research has expressed residues of various crops as an equivalent of flat, small grain. This becomes difficult as the density of the residue changes with weathering, or as crops other than the major cultivated crops are grown. Soil losses due to wind erosion were determined by covering various percentages of the soil surface with simulated flat residues (wood dowels 3.1 to 25.4 mm in diameter). Covering 20% of the soil surface reduced soil losses 57%, and a 50% cover reduced soil losses 95%. The expression SLR = 1.81 e/sup x/ where x = /sup -0.072% SC/ describes the relationship between soil loss ratio (SLR) and percent soil cover (% SC) with a correlation coefficient of -0.94 (soil cover limits 8 to 80%). The cover can be any nonerodible material such as large clods, gravel, cotton gin trash, or any diameter stick between 3.1 and 25.4 mm. Percent soil cover is easily measured in the field or can be estimated with a minimum of training and experience.

  10. Alternative crops

    International Nuclear Information System (INIS)

    Andreasen, L.M.; Boon, A.D.

    1992-01-01

    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.)

  11. Produção de milho em plantio direto com adubação nitrogenada e cobertura do solo na pré-safra Corn in no-till system with nitrogen fertilization and soil cover crops preceding

    Directory of Open Access Journals (Sweden)

    Itamar Andrioli

    2008-08-01

    Full Text Available A utilização de plantas de cobertura de solo em pré-safra é uma alternativa para fornecer nitrogênio (N ao milho e viabilizar o sistema plantio direto nas Regiões Sudeste, Centro-Oeste, Norte e Nordeste, com inverno seco. Este estudo teve o objetivo de avaliar o efeito de doses de N e de espécies de plantas de cobertura, cultivadas em pré-safra, no fornecimento de N e na produtividade de milho em plantio direto. O delineamento experimental foi de blocos ao acaso, com parcelas subdivididas e quatro repetições. O estudo foi desenvolvido de 2000 a 2003. Os tratamentos principais foram constituídos de quatro sistemas de uso e manejo: milho em plantio direto após crotalária (PDcrot; milho em plantio direto após braquiária no primeiro ano e lablab nos dois últimos (PDlab; milho em plantio direto após milheto (PDmil; milho em plantio convencional após pousio (PC; e os secundários de três doses de N em cobertura para o milho (0, 60 e 120 kg ha-1. Foram avaliados, no milho, massa da matéria seca da parte aérea, produtividade de grãos, N acumulado e eficiência de utilização do N. A maior eficiência de utilização do N pelas plantas de milho ocorreu nos sistemas de plantio direto e crotalária em pré-safra e plantio convencional após pousio, que não diferiu entre os dois sistemas e foram superiores à dos sistemas de plantio direto em que foram utilizados lablab e milheto em pré-safra, que também não diferiram entre si. A máxima produtividade de grãos de milho foi de 7.259; 7.234; 6.723 e 6.461 kg ha-1, nas doses de N de 97,1; 120,0; 87,8 e 96,1 kg ha-1 nos sistemas plantio direto e crotalária, plantio convencional, plantio direto e lablab, e plantio direto e milheto em pré-safra, respectivamente (média dos três anos. No cultivo de milho em sistema de plantio direto a utilização de crotalária proporcionou maior produtividade em relação ao milheto e lablab em pré-safra.The use of cover crops preceding corn is an

  12. Impact of crop rotation and soil amendments on long-term no-tilled soybean yields

    Science.gov (United States)

    Continuous cropping systems without cover crops are perceived as unsustainable for long-term yield and soil health. To test this, cropping sequence and cover crop effects on soybean (Glycine max L.) yields were assessed. Main effects were 10 cropping sequences of soybean, corn (Zea mays L.), and co...

  13. Consorciação de plantas de cobertura antecedendo o milho em plantio direto: I - Dinâmica do nitrogênio no solo Cover crop mixtures preceding no-till corn: I - Soil nitrogen dynamics

    Directory of Open Access Journals (Sweden)

    C. Aita

    2004-08-01

    ém que o potencial de perdas de N por lixiviação foi maior após a ervilhaca solteira do que após a aveia e o nabo solteiros e os consórcios de aveia e ervilhaca.The dynamics of nitrogen in soils under no-tillage in Southern Brazil are poorly studied so far. A field experiment on a typic Hapludalf on the experimental area of the Soil Science Department, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul State, Brazil, was carried out in 1998/99 and 1999/00 to evaluate the effect of single crop and mixtures of black oat (BO (Avena strigosa Schieb, common vetch (CV (Vicia sativa L. and oilseed radish (OR (Raphanus sativus L. var. oleiferus Metzg. on the soil nitrogen (N dynamics. The experiment was set in a complete randomized block design with four replications. The treatments were: 100 % BO (80 kg ha-1 of seeds, 100 % CV (80 kg ha-1, 100 % OR (14 kg ha-1, 15 % BO + 85 % CV, 45 % BO + 55 % CV, and 30 % BO + 70 % OR. Additionally, two plots under winter fallow were also used for comparison. Other two control treatments were corn cultivated without N fertilizer in one plot and fertilized with 180 kg ha-1 of N-urea in another one. Mineral soil N was measured nine times, beginning ten days after cover crops were killed. Samples were taken from the 0-5, 5-15, 15-30, 30-60, and 60-90 cm soil layers. The sum of mineral N in the five soil depths was greater for single common vetch than for fallow and single BO treatment. At the end of the first month, common vetch had already approximately 30 kg ha-1 more N than the other treatments. The soil under oilseed radish had lower mineral N contents than single common vetch and similar values to those of the mixture between oat and common vetch. The results of this study indicated that the oat-vetch mixture reduced the amount of mineral soil N in relation to single vetch and this effect was proportional to the amount of oat in the crop mixture. It was also verified that the potential N loss by leaching was greater

  14. Input of dry matter by roots and shoots of summer cover cropsAporte de matéria seca por raízes e parte aérea de plantas de cobertura de verão

    Directory of Open Access Journals (Sweden)

    Cristiane de Conti Medina

    2013-05-01

    Full Text Available The advantages of using cover crops or green manures are already well known, but little is known about the contribution of the root system of these plants in the stock of organic matter in the soil. The aim of this study was to evaluate the dry matter, carbon and nitrogen supply by above ground parts and roots (down to 1.0 m deep of cover crop plants (Jack-bean – Canavalia ensiformis; velvet bean – Stizolobium niveum Kuntze; Crotalaria juncea L.; and millet – Pennisetum americanum, in sequence of corn – turnip – oat plus vetch. Trenches were dug and roots samplings were collected at seven depths (0-0.10; 0.10-0.20; 0.20-0.30; 0.30-0.40; 0.40-0, 60; 0.60-0.80; and 0.80-1.00 m. The experimental design was randomized blocks and the results were submitted to ANOVA and Tukey test. Despite millet presented the highest dry mass input (3.58 Mg ha-1 from above ground part (AGP, its C contribution from root system (RS was lower than C. juncea, because AGP/RS millet relation was 1.46 while this value for C. juncea was 0.75. Among the evaluated green manures, the roots of C. juncea contribute the most carbon (1.40 Mg ha-1 than the others, while the roots of velvet bean contribute the largest amount of nitrogen (72.38 kg ha-1 to the soil.As vantagens do uso de plantas de cobertura ou adubos verdes nos sistemas de produção já são bem conhecidas, mas pouco se sabe sobre a contribuição do sistema radicular dessas plantas no estoque de matéria orgânica do solo em profundidades maiores que 0,30 m, nas quais têm sido relatados maiores efeitos do manejo do solo, principalmente em regiões de clima tropical e subtropical. O objetivo do trabalho foi avaliar os aportes de matéria seca, C e N e a densidade de comprimento radicular até 1,0 m de profundidade de plantas de cobertura de verão (feijão-de-porco, mucuna cinza, Crotalaria juncea e milheto, bem como a profundidade efetiva das raízes e a relação parte aérea/sistema radicular (PA/SR, em

  15. CROPS Clever Robots for Crops

    NARCIS (Netherlands)

    Bontsema, J.; Hemming, J.; Pekkeriet, E.J.

    2015-01-01

    In the EU-funded CROPS project robots are developed for site-specific spraying and selective harvesting of fruit
    and fruit vegetables. The robots are being designed to harvest crops, such as greenhouse vegetables, apples,
    grapes and for canopy spraying in orchards and for precision target

  16. Climate under cover

    CERN Document Server

    Takakura, Tadashi

    2002-01-01

    1.1. INTRODUCTION Plastic covering, either framed or floating, is now used worldwide to protect crops from unfavorable growing conditions, such as severe weather and insects and birds. Protected cultivation in the broad sense, including mulching, has been widely spread by the innovation of plastic films. Paper, straw, and glass were the main materials used before the era of plastics. Utilization of plastics in agriculture started in the developed countries and is now spreading to the developing countries. Early utilization of plastic was in cold regions, and plastic was mainly used for protection from the cold. Now plastic is used also for protection from wind, insects and diseases. The use of covering techniques started with a simple system such as mulching, then row covers and small tunnels were developed, and finally plastic houses. Floating mulch was an exception to this sequence: it was introduced rather recently, although it is a simple structure. New development of functional and inexpensive films trig...

  17. Decomposition and nutrient release of leguminous plants in coffee agroforestry systems

    Directory of Open Access Journals (Sweden)

    Eduardo da Silva Matos

    2011-02-01

    Full Text Available Leguminous plants used as green manure are an important nutrient source for coffee plantations, especially for soils with low nutrient levels. Field experiments were conducted in the Zona da Mata of Minas Gerais State, Brazil to evaluate the decomposition and nutrient release rates of four leguminous species used as green manures (Arachis pintoi, Calopogonium mucunoides, Stizolobium aterrimum and Stylosanthes guianensis in a coffee agroforestry system under two different climate conditions. The initial N contents in plant residues varied from 25.7 to 37.0 g kg-1 and P from 2.4 to 3.0 g kg-1. The lignin/N, lignin/polyphenol and (lignin+polyphenol/N ratios were low in all residues studied. Mass loss rates were highest in the first 15 days, when 25 % of the residues were decomposed. From 15 to 30 days, the decomposition rate decreased on both farms. On the farm in Pedra Dourada (PD, the decomposition constant k increased in the order C. mucunoides < S. aterrimum < S. guianensis < A. pintoi. On the farm in Araponga (ARA, there was no difference in the decomposition rate among leguminous plants. The N release rates varied from 0.0036 to 0.0096 d-1. Around 32 % of the total N content in the plant material was released in the first 15 days. In ARA, the N concentration in the S. aterrimum residues was always significantly higher than in the other residues. At the end of 360 days, the N released was 78 % in ARA and 89 % in PD of the initial content. Phosphorus was the most rapidly released nutrient (k values from 0.0165 to 0.0394 d-1. Residue decomposition and nutrient release did not correlate with initial residue chemistry and biochemistry, but differences in climatic conditions between the two study sites modified the decomposition rate constants.

  18. Author Details

    African Journals Online (AJOL)

    Njoku, J.C. Vol 2, No 2 (2006) - Articles Contributions of leguminous cover crops in yam production systems in Southeastern Nigeria: I Biomass production and weed suppression. Abstract · Vol 2, No 2 (2006) - Articles Contributions of leguminous cover crops in yam production systems in Southeastern Nigeria: II.

  19. Cover crops affecting levels of ammonium and nitrate in the soil and upland rice developmentPlantas de cobertura afetando os níveis de nitrato e amônio no solo e o desenvolvimento do arroz de terras altas

    Directory of Open Access Journals (Sweden)

    Adriano Stephan Nascente

    2013-10-01

    Full Text Available The use of cover crops in no-tillage systems (NTS increases the levels of organic matter and could increase the nitrogen content of the soil, contributing to reduce fertilizers costs. The knowledge of these processes is fundamental for deciding whether cover crops can be effectively incorporated into the agricultural production system. The objective of this study was to evaluate the effect of cover crop species on the levels of nitrate and ammonium in the soil in early upland rice development, as well upland rice yield. A field experiment was performed and treatments consisted of growing rice on five cover crops (Panicum maximum, Brachiaria ruziziensis, Brachiaria brizantha, millet and fallow in an NTS and two control treatments (Brachiaria brizantha and fallow under a conventional tillage system, CTS, (one plowing and two disking. The experimental design was a complete randomized block with three replications. The soil samples were collected during a period of six weeks (0, 7, 14, 21, 28 and 35 days in relation to upland rice sowing. The cover crops Brachiaria brizantha, Panicum maximum and Brachiaria ruziziensis in the NTS and B. brizantha fallow incorporated into the CTS favored higher levels of nitrate in the soil. In contrast, B. brizantha and fallow in the CTS and millet and P. maximum in the NTS favored the buildup of high levels of ammonium in the soil. The treatments under the plowed cover crops millet and fallow allowed for a higher upland rice yield. The tillage system and nature of the cover crops could be used to achieve the desired levels and forms of nitrogen in soil. O uso de plantas de cobertura no sistema plantio direto (SPD aumenta os níveis de matéria orgânica e pode ajudar a aumentar os teores de nitrogênio no solo contribuindo para reduzir os custos de fertilizantes. O conhecimento desse processo é fundamental para que as plantas de cobertura possam ser efetivamente incorporadas aos sistemas de produção agrícola. O

  20. Can sea trout Salmo trutta compromise successful eradication of Gyrodactylus salaris by hiding from CFT Legumin (rotenone) treatments?

    DEFF Research Database (Denmark)

    Davidsen, J. G.; Thorstad, E. B.; Baktoft, H.

    2013-01-01

    In this study, 34 anadromous brown trout (sea trout) Salmo trutta were equipped with acoustic transmitters in order to examine whether they performed avoidance behaviour in response to a CFT Legumin (rotenone) treatment in the Norwegian River Vefsna. Migratory behaviour of the S. trutta was monit......In this study, 34 anadromous brown trout (sea trout) Salmo trutta were equipped with acoustic transmitters in order to examine whether they performed avoidance behaviour in response to a CFT Legumin (rotenone) treatment in the Norwegian River Vefsna. Migratory behaviour of the S. trutta...

  1. Evidence for linkages between ecoenzyme activity and soil organic matter chemistry following encroachment of leguminous woody plant into grasslands.

    Science.gov (United States)

    Filley, Timothy; Stott, Diane; Boutton, Thomas; Creamer, Courtney; Olk, Dan

    2010-05-01

    respect to bulk Corg accrual. The opposite relationship between PPO and lignin indicates a suppression of PPO activity possibly by N-accrual in this leguminous system. Other relationships are evident among enzymes and land cover/age profiles and will be discussed. These results have important implications for the modeling of woodland-grassland conversion and the dynamics of biogeochemical cycles in this globally significant land cover change.

  2. Introducción de cultivos de cobertura en la rotación soja-maíz: efecto sobre algunas propiedades del suelo Inclusion of cover crops in a soybean-corn rotation: effect on some soil properties

    Directory of Open Access Journals (Sweden)

    Silvina Beatriz Restovich

    2011-07-01

    -tillage (NT show a progressive decline in their physical and chemical fertility. The inclusion of cover crops (CC in these agricultural systems could help mitigate these types of degradation. The objectives of this study were: 1 to evaluate the effect of different CC on some soil properties (porosity distribution, structural stability, bulk density, soil organic carbon (SOC and labile carbon and 2 to analyze the evolution of these properties during the inclusion of CC in a soybean-corn rotation under NT. In 2005, a two-year study was carried out on a silt loam Typic Argiudoll using different winter species as CC: barley (Hordeum vulgare L., ryegrass (Lolium multiflorum L., oats (Avena sativa L., rescue grass (Brumus unioloides L., vetch (Vicia sativa L., rape seed (Brassica napus L. and forage radish (Raphanus sativus L., a mixture of vetch and oats, and a control without CC. We measured an increase in soil macroporosity and structural stability and an increase in SOC content and the labile fraction. These changes were of moderate to low magnitude, occurring mainly near the soil surface (0-5 cm; they were associated with moments of important residue contributions and disappeared in periods of heavy rain. The rotations that included CC accumulated more SOC. Forage radish outstanded as a generator of porosity and oats as a stabilizer of the porous system.

  3. Produção de biomassa por cultivos de cobertura do solo e produtividade do algodoeiro em plantio direto Cover crops biomass production and cotton yield in no-tillage system

    Directory of Open Access Journals (Sweden)

    Alexandre Cunha de Barcellos Ferreira

    2010-06-01

    Full Text Available O objetivo deste trabalho foi avaliar a produção, a persistência da matéria seca e a eficiência da dessecação em espécies vegetais utilizadas para cultivos de cobertura do solo, e quantificar seus efeitos sobre a produtividade do algodoeiro em plantio direto. O trabalho foi realizado em Santa Helena de Goiás, GO, com 16 tratamentos: Panicum maximum, cultivares Mombaça, Tanzânia e Massai; Urochloa brizantha, cultivares Piatã, Xaraés, Marandu e MG4; U. decumbens; Paspalum atratum cv. Pojuca; Sorghum bicolor cultivares Santa Eliza e BRS 700; Pennisetum glaucum cv. ADR 500; Raphanus sativus; Eleusine coracana, Crotalaria spectabilis, além da testemunha em pousio. As espécies foram semeadas no início de março (2007. As espécies com menores produtividades e persistência da matéria seca foram C. spectabilis, E. coracana e R. sativus. As produtividades de algodão em caroço e fibra foram maiores no cultivo sobre palhas residuais das cultivares Tanzânia e Mombaça de P. maximum, em comparação às observadas com uso de P. atratum cv. Pojuca, R. sativus e pousio. Em geral, S. bicolor, P. glaucum e as cultivares Tanzânia e Mombaça de P. maximum, e MG4, Piatã e Xaraés de U. brizantha apresentam produção e persistência da matéria seca adequadas para o cultivo do algodoeiro no sistema de plantio direto, no cerrado brasileiro.The objectives of this work were to evaluate biomass production and persistence and the desiccation efficiency in plant species used as cover crops, and to quantify its effects on cotton yield in a no-tillage system. The study was carried out in Santa Helena de Goiás, GO, Brazil, using 16 plant species: Panicum maximum, cultivars Mombaça, Tanzânia and Massai; Urochloa brizantha, cultivars Piatã, Xaraés, Marandu and MG4; U. decumbens; Paspalum atratum cv. Pojuca; Sorghum bicolor cultivars Santa Eliza and BRS 700; Pennisetum glaucum cv. ADR 500; Raphanus sativus; Eleusine coracana, Crotalaria spectabilis

  4. Atributos físicos do solo sob diferentes preparos e coberturas influenciados pela distribuição de poros Soil physical attributes under different tillage systems and cover crops, as influenced by pore distribution

    Directory of Open Access Journals (Sweden)

    Eurâimi de Q. Cunha

    2010-11-01

    Full Text Available Com este trabalho se propõe avaliar a influência da distribuição de poros sobre alguns atributos físicos do solo sob semeadura direta (SD e preparo convencional (PC, cultivado com diferentes culturas de cobertura, no sistema de produção orgânica de feijão e milho. O trabalho foi conduzido em Santo Antônio de Goiás, GO, em Latossolo Vermelho distrófico. Em novembro de 2003 foram instalados quatro experimentos, dois em SD e dois em PC, um em cada manejo com feijão e o outro com milho. Foram comparados em blocos ao acaso com quatro repetições, crotalária, guandu, mucuna-preta, sorgo e pousio. Amostragens de solo das parcelas e de uma mata próxima foram realizadas nas profundidades de 0-0,10 e 0,10-0,20 m, em novembro de 2007, para determinação do teor de matéria orgânica (M.O. e de atributos físicos do solo. O uso do solo sob vegetação de cerrado para a produção agrícola, independentemente do sistema de cultivo, resultou em redução na porosidade total (Pt, macroporosidade (Mp e capacidade de aeração do solo (CAS. Os atributos físicos do solo foram afetados favoravelmente pela M.O. As variações em Pt, Mp, CAS e capacidade de água disponível do solo podem ser explicadas pela variação na distribuição do tamanho de poros do solo, principalmente daqueles com ∅ > 0,075 mm.This study aimed to evaluate the influence of pore distribution on some physical attributes of soil under no-tillage (NT and conventional tillage (CT systems, cultivated with different cover crops, in organic production of common bean and corn. The work was carried out in Santo Antônio de Goiás, GO, on an Oxisol. In November 2003 four experiments were installed, two of them under NT and the other two under CT. In each soil tillage system, an experiment was conducted with corn and another with common bean. Sunn hemp, pigeon pea, velvet bean, sorghum, and fallow were compared in a randomized block design, with four replications. Samples were

  5. Benthic Cover

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic cover (habitat) maps are derived from aerial imagery, underwater photos, acoustic surveys, and data gathered from sediment samples. Shallow to moderate-depth...

  6. Diversity of rhizobia associated with leguminous trees growing in South Korea.

    Science.gov (United States)

    Kang, Jun Won; Song, Jaekyeong; Doty, Sharon L; Lee, Don Koo

    2013-03-01

    This study was carried out to examine the diversity of 34 isolates collected from 11 species of leguminous trees growing in South Korea. Phylogenetic relationships between these 34 isolates and reference strains of the Azorhizobium, Bradyrhizobium, Mesorhizobium, Rhizobium and Ensifer/Sinorhizobium were analysed by using 16S rRNA gene sequences. Twenty-one isolates were related to Mesorhizobium, four isolates to Rhizobium, and nine isolates to Bradyrhizobium. But none of isolates were related to Sinorhizobium/Ensifer and Azorhizobium. Robinia pseudoacacia and Amorpha fruticosa were nodulated by various genotypes of rhizobia out of them, most of the isolates belonged to the genus Mesorhizobium. The isolates from Lespedeza bicolar belonged to diverse genera of Mesorhizobium, Rhizobium, and Bradyrhizobium. The isolates from Maackia amurensis and Lespedeza maximowiezii var. tomentella were phylogenetically related to the genera of Bradyrhizobium. PCR-based RAPD method and phylogenetic analysis of the 16S rRNA results revealed a high phylogenetic diversity of rhizobial strains nodulating leguminous trees in South Korea. Also, the relationships between host and bacterial phylogenies showed that only Robinia pseudoacacia, and Wisteria floribunda have significantly unique branch length than expected by chance based on phylogenetic tree. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Increase of multi-metal tolerance of three leguminous plants by arbuscular mycorrhizal fungi colonization.

    Science.gov (United States)

    Lin, Ai-Jun; Zhang, Xu-Hong; Wong, Ming-Hung; Ye, Zhi-Hong; Lou, Lai-Qing; Wang, You-Shan; Zhu, Yong-Guan

    2007-12-01

    A greenhouse pot experiment was conducted to investigate the effects of the colonization of arbuscular mycorrhizal fungus (AMF) Glomus mosseae on the growth and metal uptake of three leguminous plants (Sesbania rostrata, Sesbania cannabina, Medicago sativa) grown in multi-metal contaminated soil. AMF colonization increased the growth of the legumes, indicating that AMF colonization increased the plant's resistance to heavy metals. It also significantly stimulated the formation of root nodules and increased the N and P uptake of all of the tested leguminous plants, which might be one of the tolerance mechanisms conferred by AMF. Compared with the control, colonization by G. mosseae decreased the concentration of metals, such as Cu, in the shoots of the three legumes, indicating that the decreased heavy metals uptake and growth dilution were induced by AMF treatment, thereby reducing the heavy metal toxicity to the plants. The root/shoot ratios of Cu in the three legumes and Zn in M. sativa were significantly increased (P<0.05) with AMF colonization, indicating that heavy metals were immobilized by the mycorrhiza and the heavy metal translocations to the shoot were decreased.

  8. Microbial community biogeographic patterns in the rhizosphere of two Brazilian semi-arid leguminous trees.

    Science.gov (United States)

    Lançoni, Milena Duarte; Taketani, Rodrigo Gouvêa; Kavamura, Vanessa Nessner; de Melo, Itamar Soares

    2013-07-01

    Arid environments are regular and well distributed over all continents and display drought characteristics whether full-time or seasonal. This study aims to characterize how the microbial communities of the rhizosphere of two leguminous trees from the Brazilian semi-arid biome the Caatinga are geographically and seasonally shaped, as well as the factors driving this variation. With that purpose, the soil rhizosphere from two leguminous trees (Mimosa tenuiflora and Piptadenia stipulacea (Benth.) Ducke) were sampled in two different seasons: rainy and drought at five different sites. Assessment of bacterial and archaeal communities occurred by T-RFLP analysis of 16S rRNA and archaeal amoA genes. By these means, it was observed that the seasons (wet and dry periods) are the factors that most influence the composition of the microbial community from both analyzed plants, except for the results obtained from the CCA applied to Archaeas. Furthermore, soil physical-chemical factors also had a significant influence on the community and indicated a geographical pattern of the bacterial community. It was not possible to observe significant modifications in the composition in relation to the plant species. We have seen that soil characteristics and rainfall were the factors that most influenced the microbial composition. Also, the bacterial community had a significant correlation with soil characteristics that indicates that these rhizosphere communities might be selected by environmental characteristics. Furthermore, the data suggest that climate plays a key role in structuring the microbial community of this biome.

  9. Phytoprotective effect of arbuscular mycorrhizal fungi species against arsenic toxicity in tropical leguminous species.

    Science.gov (United States)

    de Melo, Rangel Wesley; Schneider, Jerusa; de Souza, Costa Enio Tarso; Sousa, Soares Cláudio Roberto Fonsêca; Guimarães, Guilherme Luiz Roberto; de Souza, Moreira Fatima Maria

    2014-01-01

    Arbuscular mycorrhizal fungi (AMF) improve the tolerance of hosting plants to arsenic (As) in contaminated soils. This work assessed the phytoprotective effect of Glomus etunicatum, Acaulospora morrowiae, Gigaspora gigantea, and Acaulospora sp. on four leguminous species (Acacia mangium, Crotalaria juncea, Enterolobium contortisiliquum, and Stizolobium aterrimum) in an As-contaminated soil from a gold mining area. AMF root colonization, biomass production, As and P accumulation, as well as arsenic translocation index (TI) from roots to shoots were measured. The AMF phytoprotective effect was assessed by the P/As ratio and the activity of plant antioxidant enzymes. The AMF colonization ranged from 24 to 28%. In general, all leguminous species had low As TI when inoculated with AMF species. Inoculation of C. juncea with Acaulospora sp. improved significantly As accumulation in roots, and decreased the activity of ascorbate peroxidase (APX) and superoxide dismutase (SOD), highlighting its phytoprotective effect and the potential use of this symbiosis for phytoremediation of As-contaminated soils. However, S. aterrimum has also shown a potential for phytoremediation irrespectively of AMF inoculation. APX was a good indicator of the phytoprotective effect against As contamination in C. juncea and A. mangium. In general P/As ratio in shoots was the best indicator of the phytoprotective effect of all AMF species in all plant species.

  10. Isoflavonoids in non-leguminous taxa: a rarity or a rule?

    Science.gov (United States)

    Lapcík, Oldrich

    2007-01-01

    Isoflavonoids are characteristic metabolites in legumes and an overwhelming number of reports concerning them come from the Leguminosae. Nevertheless, the spectrum of isoflavonoid producing taxa includes the representatives of four classes of multicellular plants, namely the Bryopsida, the Pinopsida, the Magnoliopsida and the Liliopsida. At least 59 non-leguminous families have been reported to produce isoflavones sensu lato; coumestans have been reported in 3 families, coumaronochromones in 3, pterocarpans in 9 and rotenoids in 8 families. Prenylated isoflavones have been found in 15 non-leguminous families and isoflavone dimers, heterodimers or oligomers in three families. More than two hundred different isoflavonoid aglycones have been reported in non-legumes altogether. The number of individual structures is even greater if the variety of glycosides are considered. Enzymology and genetics of isoflavonoid biosynthesis have been studied almost exclusively in legumes, with the exception of a few model plants (i.e. Beta vulgaris, Arabidopsis thaliana, Nicotiana tabacum and Zea mays). The key step at the very beginning of the isoflavonoid metabolic pathway is the oxidation of flavanone connected with the migration of aryl moiety from C2 to C3 mediated by a CYP450 enzyme isoflavone synthase (IFS), which has been identified and cloned in multiple legumes and in sugar beet (Beta vulgaris, Chenopodiaceae). No information is available about the enzyme(s) responsible for the biosynthesis of isoflavonoid core in other taxa. Experimental data demonstrates the capability of numerous enzymes of non-legume origin to metabolize isoflavones as alternative substrates to other phenolics.

  11. Hijacking of leguminous nodulation signaling by the rhizobial type III secretion system.

    Science.gov (United States)

    Okazaki, Shin; Kaneko, Takakazu; Sato, Shusei; Saeki, Kazuhiko

    2013-10-15

    Root-nodule symbiosis between leguminous plants and nitrogen-fixing bacteria (rhizobia) involves molecular communication between the two partners. Key components for the establishment of symbiosis are rhizobium-derived lipochitooligosaccharides (Nod factors; NFs) and their leguminous receptors (NFRs) that initiate nodule development and bacterial entry. Here we demonstrate that the soybean microsymbiont Bradyrhizobium elkanii uses the type III secretion system (T3SS), which is known for its delivery of virulence factors by pathogenic bacteria, to promote symbiosis. Intriguingly, wild-type B. elkanii, but not the T3SS-deficient mutant, was able to form nitrogen-fixing nodules on soybean nfr mutant En1282. Furthermore, even the NF-deficient B. elkanii mutant induced nodules unless T3SS genes were mutated. Transcriptional analysis revealed that expression of the soybean nodulation-specific genes ENOD40 and NIN was increased in the roots of En1282 inoculated with B. elkanii but not with its T3SS mutant, suggesting that T3SS activates host nodulation signaling by bypassing NF recognition. Root-hair curling and infection threads were not observed in the roots of En1282 inoculated with B. elkanii, indicating that T3SS is involved in crack entry or intercellular infection. These findings suggest that B. elkanii has adopted a pathogenic system for activating host symbiosis signaling to promote its infection.

  12. Does nitrogen affect the interaction between a native hemiparasite and its native or introduced leguminous hosts?

    Science.gov (United States)

    Cirocco, Robert M; Facelli, José M; Watling, Jennifer R

    2017-01-01

    Associations between plants and nitrogen (N)-fixing rhizobia intensify with decreasing N supply and come at a carbon cost to the host. However, what additional impact parasitic plants have on their leguminous hosts' carbon budget in terms of effects on host physiology and growth is unknown. Under glasshouse conditions, Ulex europaeus and Acacia paradoxa either uninfected or infected with the hemiparasite Cassytha pubescens were supplied (high nitrogen (HN)) or not (low nitrogen (LN)) with extra N. The photosynthetic performance and growth of the association were measured. Cassytha pubescens significantly reduced the maximum electron transport rates and total biomass of U. europaeus but not those of A. paradoxa, regardless of N. Infection significantly decreased the root biomass of A. paradoxa only at LN, while the significant negative effect of infection on roots of U. europaeus was less severe at LN. Infection had a significant negative impact on host nodule biomass. Ulex europaeus supported significantly greater parasite biomass (also per unit host biomass) than A. paradoxa, regardless of N. We concluded that rhizobia do not influence the effect of a native parasite on overall growth of leguminous hosts. Our results suggest that C. pubescens will have a strong impact on U. europaeus but not A. paradoxa, regardless of N in the field. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  13. Pattern of fecal endogenous nitrogen excretion in rats fed leguminous diets.

    Science.gov (United States)

    Domene, S M; de Oliveira, A C

    1996-02-01

    The main objective of this investigation was to establish the pattern in relation to time of the rat fecal endogenous nitrogen excretion by continuous feeding of balanced diets containing common peas, cowpeas or common beans as the protein sources (10% protein), labeled with 1.000 atoms % of 15N-excess. Nitrogen of endogenous origin was measured by the isotope dilution method in a 6-day experiment. Fecal excretion of endogenous nitrogen of rats fed the leguminous diets was roughly twice that of rats fed the non-protein diet (88 mg, 42 mg), and the excretion of total fecal nitrogen did not differ among leguminous diets. From the third to the sixth day of the experiment, the endogenous nitrogen excretion, either as a percentage of quantity (mg), attained a statistically non different value (p > 0.05). A common pattern of excretion of fecal endogenous nitrogen as a function of time was expressed by a strong negative (r nitrogen did not show a common pattern as a function of time for all experimental diets.

  14. Biogenesis of protein bodies during legumin accumulation in developing olive (Olea europaea L.) seed.

    Science.gov (United States)

    Jimenez-Lopez, Jose C; Zienkiewicz, Agnieszka; Zienkiewicz, Krzysztof; Alché, Juan D; Rodríguez-García, Maria I

    2016-03-01

    Much of our current knowledge about seed development and differentiation regarding reserves synthesis and accumulation come from monocot (cereals) plants. Studies in dicotyledonous seeds differentiation are limited to a few species and in oleaginous species are even scarcer despite their agronomic and economic importance. We examined the changes accompanying the differentiation of olive endosperm and cotyledon with a focus on protein bodies (PBs) biogenesis during legumin protein synthesis and accumulation, with the aim of getting insights and a better understanding of the PBs' formation process. Cotyledon and endosperm undergo differentiation during seed development, where an asynchronous time-course of protein synthesis, accumulation, and differential PB formation patterns was found in both tissues. At the end of seed maturation, a broad population of PBs, particularly in cotyledon cells, was distinguishable in terms of number per cell and morphometric and cytochemical features. Olive seed development is a tissue-dependent process characterized by differential rates of legumin accumulation and PB formation in the main tissues integrating seed. One of the main features of the impressive differentiation process is the specific formation of a broad group of PBs, particularly in cotyledon cells, which might depend on selective accumulation and packaging of proteins and specific polypeptides into PBs. The nature and availability of the major components detected in the PBs of olive seed are key parameters in order to consider the potential use of this material as a suitable source of carbon and nitrogen for animal or even human use.

  15. Maize crop residue uses and trade-offs on smallholder crop-livestock farms in Zimbabwe: Economic implications of intensification

    NARCIS (Netherlands)

    Rusinamhodzi, L.; Wijk, van M.T.; Corbeels, M.; Rufino, M.C.; Giller, K.E.

    2015-01-01

    Decisions to use crop residues as soil cover for conservation agriculture create trade-offs for farmers who own cattle in crop-livestock systems. Trade-offs among soil C, crop and animal and crop productivity were analysed using the NUANCES-FARMSIM (FArm-scale Resource Management SIMulator) dynamic

  16. Infection structures of host-specialized isolates of Uromyces viciae-fabae and other species of Uromyces infecting leguminous crops

    NARCIS (Netherlands)

    Emeran, A.A.; Sillero, J.C.; Niks, R.E.; Rubiales, D.

    2005-01-01

    A study was made of the morphology of urediniospores and primary infection structures of 12 isolates of six legume-infecting species of Uromyces. Infection structures were sufficient to distinguish among species. Isolates of Uromyces viciae-fabae proved to be specialized with respect to host,

  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. 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. With the......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....... With the aim to enhance productivity, a number of functional stay-green cultivars have been selected by conventional breeding, in particular of sorghum and maize. In many cases, a positive correlation between leaf area duration and yield has been observed, although in a number of other cases, stay......-green cultivars do not display significant effects with regards to productivity. In several crops, the stay-green phenotype is observed to be associated with a higher drought resistance and a better performance under low nitrogen conditions. Among the approaches used to achieve stay-green phenotypes in transgenic...

  19. Desempenho agronômico e econômico do milho irrigado em sucessão a espécies invernais de cobertura de solo e/ou para produção de grãos Agronomic and economic performance of maize irrigated in succession to winter cover crops and/or to species for grain production

    Directory of Open Access Journals (Sweden)

    Adriano Alves da Silva

    2008-06-01

    Full Text Available As espécies de cobertura de solo no inverno melhoram as características de solo, podendo apresentar também vantagens econômicas. Assim, é importante introduzir espécies de inverno que, além de palha, possam produzir grãos para aumentar a rentabilidade e a sustentabilidade da atividade agrícola. O objetivo desta pesquisa foi avaliar, em três estações de crescimento, os desempenhos agronômico e econômico do milho irrigado em sucessão a espécies invernais para cobertura de solo e/ou para produção de grãos, cultivado sob dois níveis de nitrogênio (N em cobertura. A pesquisa foi conduzida nas estações de crescimento 2003/04, 2004/05 e 2005/06, no município de Eldorado do Sul, RS. Nos três anos, os tratamentos constaram do cultivo do milho irrigado em sucessão a cinco espécies de inverno e ao pousio, como testemunha. O custo de produção do milho em sucessão à ervilhaca comum é menor do que o da aveia preta e do nabo forrageiro. Das espécies invernais de cobertura de solo e de produção de grãos, a margem bruta obtida com o trigo é maior que a com a aveia branca. As vantagens econômicas do uso do nabo forrageiro e da ervilhaca comum como culturas antecessoras ao milho irrigado em relação às espécies poáceas apenas ocorrem sob baixos níveis de N aplicados em cobertura no milho.The growing of winter crop species results in benefits on soil characteristics, and can present economic advantages. Thus, it is important to introduce winter species that, besides straw, produce grains to increase the performance and the sustentability of agricultural activity. The objective of this research was to evaluate, in three growing seasons, the agronomic and economic performance of maize crop grown in succession to five winter cover crops and/or for grain production, cultivated under two rates of side dressing N fertilization. The experiment was carried out in the growing seasons of 2003/04, 2004/05 and 2005/06, in the state of

  20. Nitrogen input effectiveness on carbon sequestration in rainfed cropping system

    Science.gov (United States)

    Novara, Agata; Gristina, Luciano; Poma, Ignazio

    2016-04-01

    The combined effect of total N and C/N ratio had a large influence on the decomposition rate and consequently on potential soil organic carbon sequestration. The aim of the work was to evaluate Carbon sequestration potentiality under three mineral N fertilization levels in interaction with two cropping systems characterized by addition of N input due to leguminous species in the rotation. The study was carried out in the semiarid Mediterranean environment in a 18years long-term experiment. Is well know that in the semiarid environment the excess of N fertilization reduces biomass yield and the consequent C input. On the contrary, both N and C input determine high difference in C/N input ratio and faster organic matter mineralization. Results showed no influence of N fertilization on SOC sequestration and a reduction of SOC stock due to crop rotation due to lower C input. Crop residue quality of durum wheat-pea crop rotation characterized by a faster decomposition rate could explain the lower ability of crop rotation to sequester C in the semiarid environment.

  1. Larvicidal activity of leguminous seeds and grains against Aedes aegypti and Culex pipiens pallens.

    Science.gov (United States)

    Jang, Young-Su; Baek, Bong-Rae; Yang, Young-Cheol; Kim, Moo-Key; Lee, Hoi-Seon

    2002-09-01

    Larvicidal activity of methanol extracts of 26 leguminous seeds and 20 grains against early 4th-stage larvae of Aedes aegypti and Culex pipiens pallens was examined. At 200 ppm of the extracts from Cassia obtusifolia, Cassia tora, and Vicia tetrasperma, more than 90% mortality was obtained in larvae of Ae. aegypti and Cx. pipiens pallens. Extract of C. tora gave 86.7 and 100% mortality in the larvae of Ae. aegypti and Cx. pipiens pallens at 40 ppm but 59.2 and 78.3% mortality against larvae of Ae. aegypti and Cx. pipiens pallens at 20 ppm, respectively. At 40 ppm, extract of C. obtusifolia caused 51.4 and 68.5% mortality of the 4th-stage larvae of Ae. aegypti and Cx. pipiens pallens, respectively. Larvicidal activity of extract of C obtusifolia was significantly reduced when used at 20 ppm. Further studies of these plants as possible agents for mosquito control are warranted.

  2. 15N2 Fixation and H2 Evolution by Six Species of Tropical Leguminous Trees 1

    Science.gov (United States)

    van Kessel, Christopher; Roskoski, Joann P.; Wood, Timothy; Montano, Jorge

    1983-01-01

    The C2H4/15N2 and H2/15N2 ratios for six species of tropical leguminous trees are reported. C2H4/15N2 ratios ranged from 2.4 to 4.7; values for the H2/15N2 ratios were between 0.6 and 1.4. Relative efficiency values, based on C2H2 reduction, 15N incorporation, and H2 evolution during 15N incorporation varied between 0.68 and 0.84 for the six species. Overall, approximately 30% of the electron flow through nitrogenase was used for H2 evolution. PMID:16663109

  3. Leguminous lectins as tools for studying the role of sugar residues in leukocyte recruitment.

    Science.gov (United States)

    Alencar, N M; Teixeira, E H; Assreuy, A M; Cavada, B S; Flores, C A; Ribeiro, R A

    1999-01-01

    The natural physiological ligands for selectins are oligosaccharides found in glycoprotein or glycolipid molecules in cell membranes. In order to study the role of sugar residues in the in vivo lectin anti-inflammatory effect, we tested three leguminous lectins with different carbohydrate binding affinities in the peritonitis and paw oedema models induced by carrageenin in rats. L. sericeus lectin was more anti-inflammatory than D. virgata lectin, the effects being reversed by their specific binding sugars (N-acetylglucosamine and alpha-methylmannoside, respectively). However, V. macrocarpa, a galactose-specific lectin, was not anti-inflammatory. The proposed anti-inflammatory activity of lectins could be due to a blockage of neutrophil-selectin carbohydrate ligands. Thus, according to the present data, we suggest an important role for N-acetylglucosamine residue as the major ligand for selectins on rat neutrophil membranes. PMID:10704148

  4. The use of nitrogen-15 labeling for the assessment of leguminous protein digestibility.

    Science.gov (United States)

    Domene, S M; de Oliveira, A C

    1993-02-01

    This study evaluated the digestibility of leguminous protein labeled with 15N, by using nitrogen balance and quantitation of fecal endogenous nitrogen (FEN), determined by isotopic dilution, in order to correct apparent values. Seeds of common beans, cowpea and common pea labeled with 1.000 atoms% of 15N-excess were used as protein sources in diets for 60 male Wistar rats, during a 6-day assay. The real digestibility values obtained with FEN were 77.6, 84.4, and 86.3% for common beans, cowpea and common pea, respectively. They were higher and statistically different (p < 0.05) than true digestibility values, corrected by non-protein diet. FEN showed a direct, moderate and positive relation with weight of dry matter eaten, initial body weight, weight gain and weight of dry matter of feces, the latter showing the highest correlation, with a coefficient r = 0.8930 at 1% level.

  5. Rhizobia symbiosis of seven leguminous species growing along Xindian riverbank of Northern Taiwan

    Directory of Open Access Journals (Sweden)

    Cheng-Tai Huang

    2018-01-01

    Full Text Available Legume-rhizobia symbioses of seven leguminous species growing along Xindian riverbank of Northern Taiwan were investigated in this study. These legumes form either determinate or indeterminate types of root nodules. The determinate nodules of Alysicarpus vaginalis, Desmodium. triflorum, D. heterophyllum, Sesbania cannabina and the indeterminate nodules of Mimosa pudica harbored bacteroids of morphological uniformity (length of 1-3 μm, while the indeterminate nodules of Crotalaria zanzibarica and Trifolium repens contained bacteroids of highly pleomorphism (size varying from 1 to 5 μm. The enclosed bacteria were isolated from respective nodules, and twenty slow-growing and nine fast-growing rhizobial isolates were recovered. The slow-growing isolates were classified to the genus Bradyrhizobium based on the 16S rRNA sequences, whereas the fast-growing rhizobia comprise four genera, Neorhizobium, Rhizobium, Cupriavidus and Paraburkholderia. Results of stable isotope analyses revealed that the seven leguminous species had similar and consistently negative δ15N values in leaves (mean of -1.2 ‰, whereas the values were positive (varying from 3.7 to 7.3 ‰ in the nodules. These values were significantly higher in the indeterminate nodules than those in the determinate ones. In addition, variations in the values of leaf δ13C (varying from -29 to -34‰ among the seven legumes were measured, indicating their photosynthetic water use efficiencies were different. This is the first field survey to report the rhizobial diversity and the nutrient relationships of sympatric legume in Taiwan.

  6. Effects of cropping systems on soil biology

    Science.gov (United States)

    The need for fertilizer use to enhance soil nutrient pools to achieve good crop yield is essential to modern agriculture. Specific management practices, including cover cropping, that increase the activities of soil microorganisms to fix N and mobilize P and micronutrients may reduce annual inputs ...

  7. Índice de cobertura vegetal pela cultura do milho no período de chuvas intensas no sul de Minas Gerais Plant cover index in the period of intensive rainfall for corn crop at south of Minas Gerais state, Brazil

    Directory of Open Access Journals (Sweden)

    Fabiana Silva de Souza

    2010-04-01

    Full Text Available A cobertura vegetal é a defesa natural do solo contra a erosão hídrica. Nos modelos de estimativas de perdas de solo, o efeito da cobertura vegetal na interceptação da energia cinética da chuva é a variável chave na modelagem do processo erosivo. Assim sendo, objetivou-se avaliar a eficiência da cobertura vegetal, proporcionada pela cultura do milho, e suas relações com os atributos fitotécnicos desta cultura para alguns híbridos. O estudo foi realizado no campo demonstrativo de híbridos de milho da Universidade Federal de Lavras, localizada no município de Lavras, MG. Para determinação da cobertura vegetal utilizou-se um aparato que consiste em uma estrutura horizontal, contendo orifícios para visualização dos pontos com cobertura e sem cobertura vegetal, sendo as leituras feitas de forma aleatória e transversalmente às linhas da cultura. Os atributos fitotécnicos avaliados foram altura da planta, estande, matéria seca e produção de grãos. Diante dos resultados pode-se concluir que o maior índice de cobertura vegetal foi observado para os híbridos de milho P 30F33, P 30F90, P 3021, STRIKE, FORT, VALENT, UFLA 2001, UFLA 2004, CO 32, D 8480, D 8420 DKB 333B, DKB 440, evidenciando boa qualidade como planta protetora do solo. No período de maior ocorrência de chuvas, na região sul de Minas Gerais, a cultura do milho pode minimizar o efeito do processo erosivo. A produção de matéria seca relacionou-se bem com o índice de cobertura vegetal, podendo ser um indicativo quanto à proteção do solo.The plant cover is a natural protection of soil against water erosion. In estimative models of soil loss, the effect of plant cover in the interception of rainfall kinetic energy is the key variable in the modeling of the erosive process. Thus, the aim of this work is to evaluate the efficiency of the plant cover provided by the corn crop and their relations with the phytotechnical attributes of this crop for its respective

  8. THE STRUCTURE AND YIELD LEVEL OF SWEET CORN DEPENDING ON THE TYPE OF WINTER CATCH CROPS AND WEED CONTROL METHOD

    Directory of Open Access Journals (Sweden)

    Robert Rosa

    2014-10-01

    Full Text Available Organic manuring is suggested to be necessary in sweet corn cultivation. It is not always possible to use farmyard manure due to economic, production or technical reasons. Catch crops used as green manures can be an alternative source of organic matter. The experiment was carried out in central-east Poland (52°06’N, 22°55’E, in years 2008–2011. The successive effect of winter catch crops (hairy vetch, white clover, winter rye, Italian ryegrass, winter turnip rape and the type of weed control on the growth and yielding of sweet corn was examined. The catch crops were sown in early September, incorporated in early May. The effect of the winter catch crops on yield was compared to the effect of FYM at a rate of 30 t·ha-1 and the control without organic manuring. The sweet corn was grown directly after organic fertilization. Three methods of weed control was used: Hw – hand weeding, twice during the growing period, GCM – herbicide Guardian CompleteMix 664 SE, immediately after sowing the seed corn, Z+T – a mixture of herbicides Zeagran 340 SE + Titus 25 WG, in the 3–4 leaf stage sweet corn. The highest yields of biomass were found for winter rye (35.5 t·ha-1 FM and 7.3 t·ha-1 DM, the most of macroelements accumulated winter turnip rape (480.2 kg N+P+K+Ca+Mg·ha-1. Generally, leguminous catch crops had similar to the FYM and better than non-leguminous catch crops yield-forming effect. The highest yield of marketable ears of sweet corn was obtained after FYM (14.4 t·ha-1 and after hairy vetch catch crop (14.0 t·ha-1. A similar yield-forming effect also had white clover and Italian ryegrass. The most of ears from 1 ha was achieved after white clover catch crop (59.3 tausend, similar after FYM and hairy vetch catch crop. The highest kernel yields were found after FYM (10.7 t·ha-1. The yields of kernel after hairy vetch and white clover catch crops were significantly higher than after non-leguminous catch crops. Z+T weed control

  9. Produtividade de feijão-guará e efeito supressivo de culturas de cobertura de inverno em espontâneas de verão = Common bean yield and the suppressive effect of winter cover crops on summer weeds

    Directory of Open Access Journals (Sweden)

    Henrique von Hertwig Bittencourt

    2009-10-01

    Full Text Available Investigou-se o efeito das coberturas de inverno centeio, aveia, azevém, ervilhaca e nabo forrageiro (e suas associações, em sistema de plantio direto, sobre a cobertura do solo e a produção de biomassa das coberturas de inverno, sobre a biomassa de plantas espontâneas deverão, no período crítico de competição, e sobre a produtividade do feijão, cv Guará. O experimento foi instalado em delineamento experimental constituído por blocos ao acaso com quatro repetições. Observaram-se as maiores percentagens de cobertura do solo no inverno, com os tratamentos centeio + ervilhaca, centeio + ervilhaca + nabo forrageiro e aveia + ervilhaca; a produção de biomassa de cobertura foi maior com centeio + ervilhaca + nabo forrageiro. Oefeito de supressão observado foi maior no monocultivo de azevém e no consórcio de centeio + ervilhaca + nabo forrageiro, porém não foi detectada correlação da biomassa de cobertura com a supressão de plantas espontâneas de verão. Os melhores rendimentos de feijão foram obtidos com o monocultivo de azevém, monocultivo de aveia e combinação centeio + ervilhaca, que atingiram 1.950, 1.730 e 1.790 kg ha-1, respectivamente. O azevém e a aveia em monocultivo apresentaram os menores custos com sementes e as maiores receitas, ou seja, os maiores retornos por unidade monetária investida.The effect of the winter cover crops rye, oat, ryegrass, vetch and fodder radish (and their mixtures in no-tillage systems was investigated on soil cover, cover crop biomass and summer weed biomass during the critical competition stage with common bean. Bean yield was also evaluated. The experimental design was randomized complete blocks and four repetitions. The highest soil cover during winter was observed in the treatments rye + vetch, rye + vetch +fodder radish and oat + vetch. The highest values of cover crops biomass production were observed in the treatments rye + vetch + fodder radish. Weed suppression was higher

  10. Impact of integrated nutrient management on growth and grain yield of wheat under irrigated cropping system

    International Nuclear Information System (INIS)

    Nawab, K.; Amanullah, A.; Shah, P.; Arif, M.; Khan, A.M.

    2011-01-01

    Field study was conducted during 2001-02 and 2002-03 to investigate the effect of cropping patterns and farm yard manure, potassium and zinc on the grain yield of wheat. Trials were conducted at Agricultural Research Farm, KPK Agricultural University Peshawar, Pakistan. Two factors cropping patterns and manures/fertilizers were studied in the experiment. Randomized complete block design was used with split plot arrangements and four replications having net plot size of 12 m/sup 2/. Wheat variety Ghaznavi-98 was sown in November soon after ploughing the soil at proper moisture level suitable for wheat seed germination. Five cropping patterns were allotted to main plots and the eight combinations of FYM, K and Zn to the sub-plots. Same plots were used for next year sowing. Effects of five cropping patterns i.e., rice-wheat, maize-wheat, sunflower-wheat, sorghum-wheat and pigeon pea-wheat and three organic and in-organic fertilizers (Farmyard Manure, Potassium and Zinc) on subsequent wheat crop were observed. Highest grain yield was obtained when wheat was planted after pigeon pea. Manures/fertilizer application (Farmyard Manure, Potassium and Zinc) produced significantly higher grain yield than the control plots. The findings of the present study revealed that leguminous crops can significantly increase the yield of succeeding crops. Thus use of Farmyard Manure, Potassium and Zinc should be included in integrated crop management approaches for sustainable agriculture. (author)

  11. Nitrous oxide emissions from crop sequences of grass-clover and wheat

    Science.gov (United States)

    Fuß, Roland; Blank, Britta; Christen, Olaf; Munch, Jean Charles; Neuhoff, Daniel; Schmid, Harald; Freibauer, Annette

    2013-04-01

    Organic farming is based on the principle of farm internal nitrogen cycling. Soil N input is managed by fertilization with manure if there is animal stock at the farm. Stockless farms use so called Green Manure, i.e., leguminous crops integrated in a crop sequence of cash crops. A mix of grass and clover is commonly used for this. The crop is either harvested and residues incorporated or whole plants are mulched and incorporated. In order to estimate greenhouse gas (GHG) emissions from organic farming and derive management recommendations, nitrous oxide (N2O) emission data from cultivation of leguminous crops is needed. Currently there is a deficit of published data, in particular for Germany. Hence, N2O fluxes from grass-clover and subsequent wheat cultivation were studied over two years at four sites, which are distributed evenly over Germany. Treatments were (i) harvest of grass-clover and incorporation of residues in fall followed by cultivation of winter wheat, (ii) incorporation of residues in spring followed by summer wheat, (iii) mulching of grass-clover and incorporation in fall followed by winter wheat, (iv) conventional winter wheat with mineral fertilizer. Treatment effects on N2O emissions were marginal compared to site effects such as soil and climate. Overall, direct emissions from the organic treatments were remarkably similar to those from conventional winter wheat with best practice application of mineral fertilizer. Incorporation in spring resulted in higher emissions than incorporation in fall, but there was no consistent difference between incorporation of residues and mulching. Based on the present study regional emission factors for crop sequences of grass-clover and wheat in Germany can be derived.

  12. Ecofunctional Traits and Biomass Production in Leguminous Tree Species under Fertilization Treatments during Forest Restoration in Amazonia

    Directory of Open Access Journals (Sweden)

    Roberto K. Jaquetti

    2016-04-01

    Full Text Available Background: Choosing the correct species and fertilization treatments is a determining factor in the success of forest restoration. Methods: A field study was conducted in a degraded area near the Balbina hydroelectric dam in Amazonas State (AM, Brazil, to evaluate two hypotheses: (i leguminous tree species exhibit differences in growth, leaf nutrient content, and photosynthetic nutrient use efficiencies; and (ii differences in these characteristics depend on the fertilization treatments to which the species have been subjected. Dipteryx odorata, Inga edulis and Schizolobium amazonicum were subjected to the following treatments: (T1 unfertilized control; (T2 post-planting chemical fertilization; (T3 post-planting organic fertilization and (T4 combined chemical and organic post-planting fertilization. Results: In general, I. edulis had the highest absolute growth rate of biomass under all of the fertilization treatments. I. edulis and S. amazonicum showed the highest growth rates under the T4 treatment. D. odorata showed the greatest responses under the T2 and T4 treatments. Native leguminous trees with higher photosynthetic performance and better nutrient use efficiency exhibited greater growth and biomass production. Conclusion: The results suggest that an adequate balance between leguminous species selection and fertilization will aid in the success of forest restoration in Amazonia.

  13. Stress tolerance, genetic analysis and symbiotic properties of root-nodulating bacteria isolated from Mediterranean leguminous shrubs in Central Spain.

    Science.gov (United States)

    Ruiz-Díez, Beatriz; Fajardo, Susana; Puertas-Mejía, Miguel Angel; de Felipe, María del Rosario; Fernández-Pascual, Mercedes

    2009-01-01

    Nine root-nodulating bacterial isolates were obtained from the leguminous shrubs Spartium junceum, Adenocarpus hispanicus, Cytisus purgans, Cytisus laburnuum, Retama sphaerocarpa and Colutea arborescens in areas of Central Spain. A poliphasic approach analyzing phenotypic, symbiotic and genetic properties was used to study their diversity and characterize them in relation to Mediterranean conditions. Stress tolerance assays revealed marked variations in salinity, extreme pH and cadmium tolerance compared with reference strains, with the majority showing salinity, alkalinity and Cd tolerance and three of them growing at acid pH. Variation within the 16S rRNA gene was examined by amplified 16S rDNA restriction analysis (ARDRA) and direct sequencing to show genetic diversity. Phylogeny confirmed the close relationship of four isolates with Bradyrhizobium canariense, three with Phylobacterium myrsinacearum, one with Rhizobium rhizogenes and another with Mesorhizobium huakuii. The cross inoculation tests revealed wide spectra of nodulation. This is the first report of P. myrsinacearum being able to nodulate these leguminous shrubs, and also the first time reported the association between B.canariense, R. rhizogenes and M. huakuii and C. laburnuum, C. purgans and C. arborescens, respectively. These results suggested that native rhizobia could be suitable candidates as biofertilizers and/or inoculants of leguminous shrubs with restoration or revegetation purposes in Mediterranean areas.

  14. Sganzerla Cover

    Directory of Open Access Journals (Sweden)

    Victor da Rosa

    2014-06-01

    Full Text Available Neste artigo, realizo uma leitura do cinema de Rogério Sganzerla, desde o clássico O bandido da luz vermelha até os documentários filmados na década de oitenta, a partir de duas noções centrais: cover e over. Para isso, parto de uma controvérsia com o ensaio de Ismail Xavier, Alegorias do subdesenvolvimento, em que o crítico realiza uma leitura do cinema brasileiro da década de sessenta através do conceito de alegoria; depois releio uma série de textos críticos do próprio Sganzerla, publicados em Edifício Sganzerla, procurando repensar as ideias de “herói vazio” ou “cinema impuro” e sugerindo assim uma nova relação do seu cinema com o tempo e a representação; então busco articular tais ideias com certos procedimentos de vanguarda, como a falsificação, a cópia, o clichê e a colagem; e finalmente procuro mostrar que, no cinema de Sganzerla, a partir principalmente de suas reflexões sobre Orson Welles, a voz é usada de maneira a deformar a interpretação naturalista.

  15. Efeito de diferentes coberturas vegetais e sistemas de preparo do solo na produção da cultura da soja = Effect of different vegetal coverings and soil tillage systems on soybean crop production

    Directory of Open Access Journals (Sweden)

    Reny Adilmar Prestes Lopes

    2007-10-01

    Full Text Available Este trabalho avaliou o desempenho da soja sob a influência de cobertura vegetal e de manejo do solo em um Latossolo Vermelho distrófico. Utilizaram-se aveia, nabo, ervilhaca, ervilha, milheto e tremoço. Avaliaram-se altura e densidade de plantas, altura de inserção de vagens, número de vagens, produtividade, massa de mil grãos, teor de água, densidade e resistência do solo à penetração. O sistema semeadura direta teve maior altura de inserção de vagens, quantidade de vagens, altura de plantas, teor de água e densidade do solo. Maiores valores de resistência do solo à penetração foram verificados no preparo convencional, porém obteve-se maior produtividade. As coberturas e os sistemas de preparo influenciaram na produtividade das plantas de soja. As coberturas vegetaispromoveram melhorias no solo com redução da compactação em algumas camadas do solo. O consórcio aveia/ervilhaca mostrou-se uma técnica de manejo inadequada para as condições às quais o solo foi submetido. O consórcio aveia/milheto mostrou ser uma opção viável de cobertura de solo antecessora à soja. A semeadura direta mostrou ser técnica demanejo adequado para o tipo de solo estudado.This study evaluated the performance of the soybean under the influence of vegetal covering and soil management in Red Latosol dystrofic. Oats, turnip, hairy vetch, pea, millet and lupine were used. The study evaluated height and density of plants, height of insertion in string beans, number of string beans, productivity, athousand grain mass, water contend, bulk density and soil resistance to penetration. The no-tillage system had greater height of insertion of string beans, amount of string beans, height of plants, water contend and soil bulk density. Greater values of soil resistance topenetration were verified in the tillage, though higher productivity was observed. The coverings and the soil tillage systems influenced the productivity of soybean plants. The

  16. 7 CFR 457.169 - Mint crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... mint crop. Cover crop. A small grain crop seeded into mint acreage to reduce soil erosion and wind... produces new mint plants at its tips or nodes. Type. A category of mint identified as a type in the Special... section 1 of the Basic Provisions, will be divided into additional basic units by each mint type...

  17. Optimization of germination time and heat treatments for enhanced availability of minerals from leguminous sprouts.

    Science.gov (United States)

    Bains, Kiran; Uppal, Veny; Kaur, Harpreet

    2014-05-01

    Germinated legumes are highly nutritious food especially for their enhanced iron bioavailability primarily because of reduction of phytates and increase in ascorbic acid with an advancement of germination period. Length of germination time followed by different heat treatments affect the nutritive value of leguminous sprouts. To optimize germination time and heat treatments for enhanced availability of iron from leguminous sprouts, three legumes namely, mungbean, chickpea and cowpea were germinated for three time periods followed by cooking of sprouts by two cooking methods ie. pressure cooking and microwaving. Optimized germination time for mungbean was 12, 16 and 20 h; 36, 48 and 60 h for chickpea and 16, 20 and 24 h for cowpea. Germination process increased ascorbic acid significantly in all the three legumes, the values being 8.24 to 8.87 mg/100 g in mungbean, 9.34 to 9.85 mg/100 g in chickpea and 9.12 to 9.68 mg/100 g in cowpea. Soaking and germination significantly reduced the phytin phosphorus in all the three legumes, the percent reduction being 5.3 to 16.1% during soaking and 25.7 to 46.4% during germination. The reduction in phytin phosphorus after pressure cooking was 9.6% in mungbean, 18.4% in chickpea and 6.1% in cowpea. The corresponding values during microwaving were 8.4, 19.7 and 4.5%. Mineral bioavailability as predicted by phytate:iron enhanced significantly with an increase in germination time. Further reduction i.e. 0.9 to 16.3% was observed in three legumes after the two heat treatments. The study concluded that the longer germination periods ie. 20 h for mungbean, 60 h for chickpea and 24 h for cowpea followed by pressure cooking for optimized time were suitable in terms of better iron availability.

  18. ARBUSCULAR MYCORRHIZAL IN THE GROWTH OF LEGUMINOUS TREES ON COALMINE WASTE ENRICHED SUBSTRATE

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    Shantau Camargo Gomes Stoffel

    2016-06-01

    Full Text Available The objective of this work was to evaluate the effects of arbuscular mycorrhizal inoculation in the growth, colonization and absorption of P and trace elements of leguminous trees on coal mine wastes. Independent assays for Mimosa scabrella Benth. (common name bracatinga, Mimosa bimucronata (DC. Kuntze (maricá and Parapiptadenia rigida (Benth. Brenan (angico-vermelho were carried out in a greenhouse on an entirely casualized experimental delineation composed of six treatments. Five coal mine autochthonous arbuscular mycorrhizal fungal isolates were tested, including Acaulospora colombiana, Acaulospora morrowiae, Dentiscutata heterogama, Rhizophagus clarus and Rhizophagus irregulars, aside from a control treatment, with four replications each. Results show that arbuscular mycorrhizal colonization was greater than 60% for Mimosa species, and up to 26% for Parapiptadenia. Overall, the fungal inoculation promoted better plant growth, with increments of up to 1430%. Phosphorous absorption was favored, especially when inoculation was done with A. colombiana, R. irregularis and A. morrowiae. Even though there was a conclusive reduction in the levels of trace elements in the plant´s shoots, the inoculation with those species of fungi promoted significant increments in the accumulated levels of As, Cu, Zn and Cr for all plant species tested. Therefore, arbuscular mycorrhizal fungi play important roles in these poor, degraded and often contaminated environments.

  19. Role of bioinoculants and organic fertilizers in fodder production and quality of leguminous tree species.

    Science.gov (United States)

    Mishra, Seema; Sharma, Satyawati; Vasudevan, Padma

    2011-01-01

    The comparative effect of dual inoculation of native N fixer (Rhizobium) and AM fungi consortia with different organic fertilizers (vermicompost and farm yard manure) on fodder production and quality of two leguminous tree species (Leucaena leucocephala (Lam) de. Wit. and Sesbania sesban (L.) Merr.) in silvopastoral system and their impact on the fodder production of un-inoculated Panicum maximum Jacq. under cut and carry system. After three years of plantation maximum tree survival was in L. leucocephala in all the treatments in comparison to S. sesban while fodder production was more in S. sesban for initial two years and in third year it accelerated in L. leucocephala. Dual inoculation with vermicompost significantly improved fodder production, fodder quality and rhizosphere microflora in L. leucocephala but in S. sesban dual inoculation was at par with single inoculation of N fixer, AM fungi and control (without inoculation). The grass production was higher with L. leucocephala for two years while in third year it was more with S. sesban. The association of Rhizobium with AM fungi in L. leucocephala was better than in S. sesban.

  20. Cinnamate 4-Hydroxylase (C4H) genes from Leucaena leucocephala: a pulp yielding leguminous tree.

    Science.gov (United States)

    Kumar, Santosh; Omer, Sumita; Patel, Krunal; Khan, Bashir M

    2013-02-01

    Leucaena leucocephala is a leguminous tree species accounting for one-fourth of raw material supplied to paper and pulp industry in India. Cinnamate 4-Hydroxylase (C4H, EC 1.14.13.11) is the second gene of phenylpropanoid pathway and a member of cytochrome P450 family. There is currently intense interest to alter or modify lignin content of L. leucocephala. Three highly similar C4H alleles of LlC4H1 gene were isolated and characterized. The alleles shared more than 98 % sequence identity at amino acid level to each other. Binding of partial promoter of another C4H gene LlC4H2, to varying amounts of crude nuclear proteins isolated from leaf and stem tissues of L. leucocephala formed two loose and one strong complex, respectively, suggesting that the abundance of proteins that bind with the partial C4H promoter is higher in stem tissue than in leaf tissue. Quantitative Real Time PCR study suggested that among tissues of same age, root tissues had highest level of C4H transcripts. Maximum transcript level was observed in 30 day old root tissue. Among the tissues investigated, C4H activity was highest in 60 day old root tissues. Tissue specific quantitative comparison of lignin from developing seedling stage to 1 year old tree stage indicated that Klason lignin increased in tissues with age.

  1. Interactions of plant growth-promoting rhizobacteria and soil factors in two leguminous plants.

    Science.gov (United States)

    Xiao, Xiao; Fan, Miaochun; Wang, Entao; Chen, Weimin; Wei, Gehong

    2017-12-01

    Although the rhizomicrobiome has been extensively studied, little is known about the interactions between soil properties and the assemblage of plant growth-promoting microbes in the rhizosphere. Herein, we analysed the composition and structure of rhizomicrobiomes associated with soybean and alfalfa plants growing in different soil types using deep Illumina 16S rRNA sequencing. Soil pH, P and K significantly affected the composition of the soybean rhizomicrobiome, whereas soil pH and N had a significant effect on the alfalfa rhizomicrobiome. Plant biomass was influenced by plant species, the composition of the rhizomicrobiome, soil pH, N, P and plant growth stage. The beta diversity of the rhizomicrobiome was the second most influential factor on plant growth (biomass). Rhizomicrobes associated with plant biomass were identified and divided into four groups: (1) positively associated with soybean biomass; (2) negatively associated with soybean biomass; (3) positively associated with alfalfa biomass; and (4) negatively associated with alfalfa biomass. Genera assemblages among the four groups differentially responded to soil properties; Group 1 and Group 2 were significantly correlated with soil pH and P, whereas Group 3 and Group 4 were significantly correlated with soil N, K and C. The influence of soil properties on the relative abundance of plant biomass-associated rhizomicrobes differed between soybean and alfalfa. The results suggest the rhizomicrobiome has a pronounced influence on plant growth, and the rhizomicrobiome assemblage and plant growth-associated microbes are differentially structured by soil properties and leguminous plant species.

  2. [Analysis of Symbiotic Genes of Leguminous Plants Nodule Bacteria Grown in the Southern Urals].

    Science.gov (United States)

    Baymiev, An Kh; Ivanova, E S; Gumenko, R S; Chubukova, O V; Baymiev, Al Kh

    2015-12-01

    Bacterial strains isolated from the nodules, tissues, and root surface of wild legumes growing in the Southern Urals related to the tribes Galegeae, Hedysareae, Genisteae, Trifolieae, and Loteae were examined for the presence in their genomes of symbiotic (sym) genes. It was found that the sym-genes are present in microorganisms isolated only from the nodules of the analyzed plants (sym+ -strains). Phylogenetic analysis of sym+ -strains on the basis of a comparative analysis of 16S rRNA gene sequences showed that sym+ -strains belong to five families of nodule bacteria: Mesorhizobium, Bradyrhizobium, Sinorhizobium, Rhizobium, and Phyllobacterium. A study the phylogeny of the sym-genes showed that the nodule bacteria of leguminous plants of the Southern Urals at the genus level are mainly characterized by a parallel evolution of symbiotic genes and the 16S rRNA gene. Thus, cases of horizontal transfer of sym genes, which sometimes leads to the formation of certain types of atypical rhizobial strains ofleguminous plants, are detected in nodule bacteria populations.

  3. Identification of symbiotic nitrogen-fixing bacteria from three African leguminous trees in Gorongosa National Park.

    Science.gov (United States)

    Teixeira, Helena; Rodríguez-Echeverría, Susana

    2016-07-01

    The symbiosis between leguminous plants and symbiotic nitrogen-fixing bacteria is a key component of terrestrial ecosystems. Woody legumes are well represented in tropical African forests but despite their ecological and socio-economic importance, they have been little studied for this symbiosis. In this study, we examined the identity and diversity of symbiotic-nitrogen fixing bacteria associated with Acacia xanthophloea, Faidherbia albida and Albizia versicolor in the Gorongosa National Park (GNP) in Mozambique. To the best of our knowledge, this is the first report on the identity of symbiotic-nitrogen fixing bacteria in this region. 166 isolates were obtained and subjected to molecular identification. BOX-A1R PCR was used to discriminate different bacterial isolates and PCR-sequencing of 16S rDNA, and two housekeeping genes, glnII and recA, was used to identify the obtained bacteria. The gene nifH was also analyzed to assess the symbiotic capacity of the obtained bacteria. All isolates from F. albida and Al. versicolor belonged to the Bradyrhizobium genus whereas isolates from Ac. xanthophloea clustered with Mesorhizobium, Rhizobium or Ensifer strains. Soil chemical analysis revealed significant differences between the soils occupied by the three studied species. Thus, we found a clear delimitation in the rhizobial communities and soils associated with Ac. xanthophloea, F. albida and Al. versicolor, and higher rhizobial diversity for Ac. xanthophloea than previously reported. Copyright © 2016 Elsevier GmbH. All rights reserved.

  4. Prospects of using leguminous species in phytoremediation of total petroleum hydrocarbons polluted soils

    Directory of Open Access Journals (Sweden)

    Smaranda Masu

    2014-05-01

    Full Text Available Selecting the plant species to grow on aged petroleum hydrocarbons polluted soils is an important factor for a successful phytoremediation. Phytoremediation is a green technology that can become a promising solution for decontaminating polluted soils and ecological restoration of the landscape. Our comparative studies evaluate the effect of oil hydrocarbon pollution with high initial concentration on the growth leguminous plant species: Vicia sativa and Glycine max. The experimental block contains control variants, polluted soil unfertilized / fertilized with municipal sludge anaerobically stabilized in absence/presence of modified volcanic tuff amendment. After period of time the experiment’s soil in which plant species had grown well was sampled and analyzed for petroleum hydrocarbons removal. Both species showed promising efficiency in the phytoremediation of petroleum hydrocarbon highly polluted soils but a reduced growth of the surveyed plants was noticed. The efficiency of the petroleum hydrocarbons diminution is increased in the case of the addition of fertilizer 16.6 % for Vicia sativa and 30 % for Glycine max vs. the initial quantity. In the case of the phytoremediation of polluted soils treated with fertilizer and volcanic tuff, the efficiency of the petroleum hydrocarbons reduction was 72.9 % for Vicia sativa and 53.7 % for Glycine max.

  5. Functional congruence of rhizosphere microbial communities associated to leguminous tree from Brazilian semiarid region.

    Science.gov (United States)

    Taketani, Rodrigo Gouvêa; Kavamura, Vanessa Nessner; Mendes, Rodrigo; Melo, Itamar Soares

    2015-02-01

    Semiarid environments are characterized by the uneven spread of rain throughout the year. This leads to the establishment of a biota that can go through long periods without rain. In order to understand the dynamics of rhizosphere microbial communities across these contrasting seasons in Caatinga, we used the Ion Torrent platform to sequence the metagenome of the rhizosphere of a native leguminous plant (Mimosa tenuiflora). The annotation indicated that most abundant groups detected were the Actinobacteria and Proteobacteria, and the dominant functional groups were carbohydrate and protein metabolisms, and that in the wet season, the communities carried carbohydrate and amino acid metabolisms.The major differences observed between seasons were higher abundance of genes related to carbohydrate and amino acid metabolisms in the rainy season, indicating that the populations present might be better adapted to a higher abundance of organic matter. Besides, no clear separation of samples was detected based on their taxonomic composition whereas the functional composition indicates that samples from the rain season are more related. Altogether, our results indicate that there is al arge functional stability in these communities mostly due to the selection of features that aid the biota to endure the dry season and blossom during rain.

  6. Water extracts of Brazilian leguminous seeds as rich sources of larvicidal compounds against Aedes aegypti L.

    Science.gov (United States)

    Farias, Davi F; Cavalheiro, Mariana G; Viana, Martônio P; Queiroz, Vanessa A; Rocha-Bezerra, Lady C B; Vasconcelos, Ilka M; Morais, Selene M; Carvalho, Ana F U

    2010-09-01

    This study assessed the toxicity of seed water extracts of 15 leguminous species upon Aedes aegypti larvae. A partial chemical and biochemical characterization of water extracts, as well as the assessment of their acute toxicity in mice, were performed. The extracts of Amburana cearensis, Anadenanthera macrocarpa, Dioclea megacarpa, Enterolobium contortisiliquum and Piptadenia moniliformis caused 100% of mortalit y after 1 to 3 h of exposure. They showed LC(50) and LC(90) values ranging from 0.43 ± 0.01 to 9.06 ± 0.12 mg/mL and from 0.71 ± 0.02 to 13.03 ± 0.15 mg/mL, respectively. Among the secondary metabolite constituents, the seed water extracts showed tannins, phenols, flavones, favonols, xanthones, saponins and alkaloids. The extracts also showed high soluble proteins content (0.98 to 7.71 mg/mL), lectin (32 to 256 HU/mL) and trypsin inhibitory activity (3.64 = 0.43 to 26.19 = 0.05 gIT/kg of flour) The electrophoretic profiles showed a great diversity of protein bands, many of which already described as insecticide proteins. The extracts showed low toxicity to mice (LD(50) > 0.15 = 0.01 g/kg body weight), but despite these promising results, further studies are necessary to understand the toxicity of these extracts and their constituents from primary and secondary metabolism upon Ae. aegypti.

  7. [Growth responses of six leguminous plants adaptable in Northern Shaanxi to petroleum contaminated soil].

    Science.gov (United States)

    Shan, Bao-Qin; Zhang, Yong-Tao; Cao, Qiao-Ling; Kang, Zhen-Yan; Li, Shu-Yuan

    2014-03-01

    To select appropriate native species in Northern Shaanxi for phytoremediation, the growth index of six kinds of leguminous plants planted in petroleum contaminated soils were investigated through pot culture. Petroleum concentrations were set at 0, 5 000, 10 000, 20 000, 40 000 mg x kg(-1) respectively with three replicates. Using different levels of seed germination rate, germination time, individual height, wilting rate, dry weight and chlorophyll content in leaves of tested plants as the ecological indicator. The results showed that tested plants have significantly different responses to petroleum pollution. Compared with those planted in clean soils, seed germination rate and individual height were promoted when petroleum concentration was lower than 5000 mg x kg(-1), but inhibition occurred when petroleum concentrations were higher than 10000 mg x kg(-1). Strong endurance of Medicago sativa was observed to petroleum polluted soil, especially at lower petroleum concentration. Leaf wilting of Robinia pseudoacacia was unobserved even when petroleum concentration was 40 000 mg x kg(-1), thus displaying the potential of remediating petroleum contaminated soils. The petroleum concentration was significantly and negatively correlated with seed germination rate, individual height and dry weight, but positively correlated with chlorophyll content in leaves.

  8. Weak Evidence of Regeneration Habitat but Strong Evidence of Regeneration Niche for a Leguminous Shrub.

    Science.gov (United States)

    Delerue, Florian; Gonzalez, Maya; Michalet, Richard; Pellerin, Sylvain; Augusto, Laurent

    2015-01-01

    The identification of an ecological niche specific to the regeneration phase has mobilised significant attention. However, the importance of the regeneration niche concept remains unclear. Our main objective was to study the existence of such a regeneration niche for a leguminous shrub, Ulex europaeus. This study was carried out in southwest France in the context of water and nutrient stresses (mainly phosphorus limitation) due to the presence of nutrient-poor sandy soils. We analysed the regeneration of the species from the germination of seeds and emergence of new seedlings until the seedlings reached young shrub size. Our design included a P fertilisation treatment. We also investigated microsite characteristics (micro-topography and vegetation development) as they can interact with meteorological conditions and determine water availability for seeds and seedlings. We found that P availability controlled seedling growth and the time necessary to reach young shrub size. Water availability appeared to impact the species germination and seedlings survival. We also found that P and water availability depended on the interactions between microsite characteristics and climatic variations. Finally we found evidence that P and water availability are important ecological factors shaping the regeneration niche of the species, but we found weak evidence that any microsite would be appropriate for the regeneration of the species in the long term. Future studies regarding regeneration niches need to distinguish more clearly the ecological factors important for regeneration (the regeneration niche per se) and the physical world where the seedlings appear and develop (the regeneration habitat).

  9. Growth of a leguminous tree (Centrolobium tomentosum Guill. ex Benth.) inoculated with Rhizobium and mycorrhizal fungi.

    Science.gov (United States)

    Marques, M S; Gonçalves, L M; Lemos-Filho, J P; Rocha, D; Vale, M T; Scotti, M R

    1997-01-01

    Leguminous trees are being suggested for revegetation programs due to their ability to develop associations with rhizobia and mycorrhizal fungi. The growth of a native species of the Tropical Atlantic Forest, Centrolobium tomentosum, was evaluated in a native forest soil and in a Eucalyptus forest soil under different treatments of inoculation. C. tomentosum produced more biomass under nursery conditions after inoculation with Rhizobium BHICB-Ab1 associated with arbuscular mycorrhizal (AM). This treatment improved shoot and root growth and nodule weight under forest soil condition, while in eucalyptus soil only shoot biomass and nodule weight were significantly modified. In another experiment, using forest soil, height and stem diameter were also increased by dual inoculation procedures. The height and diameter growth promoting effect was observed when BHICB-Ab1 was used as inoculant associated with AM, but not with BHICB-Ab1 alone. In contrast, plants inoculated with BHICB-Ab3 alone were similar in height and diameter growth, to those which were inoculated with BHICB-Ab3 associated with AM. These results suggest that benefits of dual inoculation depend on triparty symbiosis and especially on the choice of Rhizobium strain.

  10. Weak Evidence of Regeneration Habitat but Strong Evidence of Regeneration Niche for a Leguminous Shrub.

    Directory of Open Access Journals (Sweden)

    Florian Delerue

    Full Text Available The identification of an ecological niche specific to the regeneration phase has mobilised significant attention. However, the importance of the regeneration niche concept remains unclear. Our main objective was to study the existence of such a regeneration niche for a leguminous shrub, Ulex europaeus. This study was carried out in southwest France in the context of water and nutrient stresses (mainly phosphorus limitation due to the presence of nutrient-poor sandy soils. We analysed the regeneration of the species from the germination of seeds and emergence of new seedlings until the seedlings reached young shrub size. Our design included a P fertilisation treatment. We also investigated microsite characteristics (micro-topography and vege