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Articles 18301 - 18330 of 59552

Full-Text Articles in Earth Sciences

Prediction Of Biome-Specific Potential Evapotranspiration In Mongolia Under A Scarcity Of Weather Data, Khulan Batsukh, Vitaly A. Zlotnik, Andrew E. Suyker, Paolo Nasta Sep 2021

Prediction Of Biome-Specific Potential Evapotranspiration In Mongolia Under A Scarcity Of Weather Data, Khulan Batsukh, Vitaly A. Zlotnik, Andrew E. Suyker, Paolo Nasta

Department of Earth and Atmospheric Sciences: Faculty Publications

We propose practical guidelines to predict biome-specific potential evapotranspiration (ETp) from the knowledge of grass-reference evapotranspiration (ET0) and a crop coefficient (Kc) in Mongolia. A paucity of land-based weather data hampers use of the Penman–Monteith equation (FAO-56 PM) based on the Food and Agriculture Organization (FAO) guidelines to predict daily ET0. We found that the application of the Hargreaves equation provides ET0 estimates very similar to those from the FAO-56 PM approach. The Kc value is tabulated only for crops in the FAO-56 guidelines but is unavailable …

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Heavy Metal And Contaminant Loading In The Oder River Floodplains And Consequences For Livestock Management, G. Schalitz, A. Behrendt Sep 2021

Heavy Metal And Contaminant Loading In The Oder River Floodplains And Consequences For Livestock Management, G. Schalitz, A. Behrendt

IGC Proceedings (1977-2023)

The predominately pristine lower Oder floodplains have experienced sedimentation and enrichment of heavy metals and contaminants since the start of industrialization in the region. With the creation of the German-Polish National Park, which included the flooded grassland area, intensive milk production has been prohibited. The objective of this research was to estimate the impact of the floodplain heavy metal and contaminant levels on the lower Oder region. Soil and plant content were analyzed for three transects according to accepted DIN methods. High content in soil did not consistently result in high plant contents; however, higher content levels were often observed …

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Extended Daylength To Increase Fall/Winter Yields Of Warm-Season Perennial Grasses, P. Mislevy, T. R. Sinclair, J. D. Ray Sep 2021

Extended Daylength To Increase Fall/Winter Yields Of Warm-Season Perennial Grasses, P. Mislevy, T. R. Sinclair, J. D. Ray

IGC Proceedings (1977-2023)

Low forage production in fall/winter months is a severe limitation for dairy and beef cattle producers in the southeastern U.S. It was hypothesized that shrt daylengths during these months induce a physiological dormancy in grasses. Four grasses [Pensacola bahiagrass, Paspalum notatum Flugge; Tifton 85 and Florakirk bermudagrass, Cynodon dactylon (L.); Florona stargrass, C. nlemfuensis Vanderyst var. nlemfuensis] were subjected to extended daylengths during the winter/fall months in a field test. Pensacola bahiagrass and Tifton 85 bermudagrass showed especially dramatic increases in forage yield during the fall/winter season under the extended daylength. Genetic elimination of daylength sensitivity in these grasses …

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Blue Carbon In South Florida's Mangroves: The Role Of Large Roots And Necromass, Zoë I. Shribman Sep 2021

Blue Carbon In South Florida's Mangroves: The Role Of Large Roots And Necromass, Zoë I. Shribman

LSU Master's Theses

Blue carbon sequestration and storage in mangroves largely result from belowground biomass allocation in response to flooded anaerobic soil conditions and nutrient availability. Biomass allocation to belowground roots is a major driver of mangrove soil formation and organic matter accumulation leading to blue carbon storage potential. Belowground biomass sampling in mangroves is labor intensive, limiting data availability on biomass stocks, particularly for large roots (>20 mm diameter) and necromass (dead roots). The mangrove nutrient model (NUMAN) uses mostly literature values to parameterize a soil cohort approach to simulate depth distribution of root mass and organic carbon concentration. We evaluated …

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Spatiotemporal Variability Of Soil Water Δ18o And Δ2h Reveals Hydrological Processes In Two Floodplain Soils, Amanda Ceming-Barbato Sep 2021

Spatiotemporal Variability Of Soil Water Δ18o And Δ2h Reveals Hydrological Processes In Two Floodplain Soils, Amanda Ceming-Barbato

LSU Master's Theses

The movement of water through soil is preferential and heterogeneous. Subsurface interactions between mobile flows and the soil matrix are not uniform and are therefore difficult to predict through time and space. The use of stable isotopes of hydrogen (2H) and oxygen (18O) as conservative tracers of water movement is improving understanding of soil hydrological processes, yet field-scale observations of isotopic variability remain scarce despite implications for identifying dominant hydrologic processes. We sampled two adjacent soils at a ridge-swale topography floodplain forest to determine soil water isotopic variability at a 20 cm depth resolution in soils …

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Nitrogen Or Water Limitation To Grassland Growth During A Moderate Dry Season In The Humid Tropics, P. Cruz, M. Boval Sep 2021

Nitrogen Or Water Limitation To Grassland Growth During A Moderate Dry Season In The Humid Tropics, P. Cruz, M. Boval

IGC Proceedings (1977-2023)

The aim of this work was to compare the effects of nitrogen and water shortage on grassland production during a moderate dry season in a tropical humid environment. The results of two experiments carried out in Guadeloupe (FWI) have shown that during dry spells, the reduction in growth of natural grasslands based on Angleton grass (Dichantium aristatum) is more easily corrected by nitrogen fertiliser application than by irrigation. This shows that it is not the availability of water, but that of nitrogen, which is limiting the primary production of Angleton grass, stands. This result is less clear for …

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Screening Brachiaria Introductions For Resistance To Spittlebugs (Homoptera: Cercopidae), José R. Valério, Cacilda Borges Do Valle, A. P. De Souza, M. C. M. Oliveira Sep 2021

Screening Brachiaria Introductions For Resistance To Spittlebugs (Homoptera: Cercopidae), José R. Valério, Cacilda Borges Do Valle, A. P. De Souza, M. C. M. Oliveira

IGC Proceedings (1977-2023)

Spittlebugs are the most evident and damaging pests of Signal grasses (Brachiaria) in tropical America. Damage caused by these insects can result in the complete loss of available forage, thereby reducing the carrying capacity of infested pastures. Host plant resistance is a low-cost method of controlling insects. High level of spittlebug resistance is found in the cultivar Marandu (B. brizantha), but it requires more fertile soils. Brachiaria germplasm provided by the International Center for Tropical Agriculture (CIAT) is available at National Beef Cattle Research Center of the Brazilian Agricultural Research Corporation (Embrapa Beef Cattle) and it …

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Mgrre_Pureoilscouttickets_Ranch, Stewart_1_21127007280000, Mgrre Sep 2021

Mgrre_Pureoilscouttickets_Ranch, Stewart_1_21127007280000, Mgrre

Legacy Scout Tickets from Pure Oil Company

No abstract provided.

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Selection Of High Yielding And Anthracnose Resistant Stylosanthes For Brazil, India And China, N. White, S. Chakraborty, Celso D. Fernandes, M. J. Charchar, N. P. Melkania, C. R. Ramesh, B. Gangaiah, Guodao Liu, D. F. Cameron, J. W. Miles Sep 2021

Selection Of High Yielding And Anthracnose Resistant Stylosanthes For Brazil, India And China, N. White, S. Chakraborty, Celso D. Fernandes, M. J. Charchar, N. P. Melkania, C. R. Ramesh, B. Gangaiah, Guodao Liu, D. F. Cameron, J. W. Miles

IGC Proceedings (1977-2023)

Resistance to anthracnose, dry matter yield (DMY) and seed yield (SY) was assessed for germplasm and breeding lines of Stylosanthes in Brazil, India and China. Overall, Stylosanthes guianensis produced higher DMY than S. scabra, S. capitata and S. macrocephala at most sites in Brazil. Data from China suggest that there are high yielding anthracnose resistant S. guianensis lines that can reduce the reliance on CIAT 184. S. seabrana might also prove successful. S. seabrana in India produced the highest DMY and SY and it can form nodules with native Bradyrhizobium strains. Regional differences in resistance within accessions stress the …

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Mgrre_Pureoilscouttickets_Iroquois Trust Co_1_21127006480000, Mgrre Sep 2021

Mgrre_Pureoilscouttickets_Iroquois Trust Co_1_21127006480000, Mgrre

Legacy Scout Tickets from Pure Oil Company

No abstract provided.

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Underground Burning Of Jharia Coal Mine (India) And Associated Surface Deformation Using Insar Data, Jungrack Kim, Shih-Yuan Lin, Ramesh P. Singh, Chen-Wei Lan, Hye-Won Yun Sep 2021

Underground Burning Of Jharia Coal Mine (India) And Associated Surface Deformation Using Insar Data, Jungrack Kim, Shih-Yuan Lin, Ramesh P. Singh, Chen-Wei Lan, Hye-Won Yun

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The underground burning in the Jharia coal mine (JCM) in India is a highly devastating environmental hazard inducing various adverse consequences. In the present study, we carried out time series analyses based on Interferometric Synthetic Aperture Radar (InSAR) and land surface temperature (LST) to study the environmental risk. First, a permanent scatterer (PS) time series analysis using Sentinel-1 images over three years was performed to detect the spatio-temporal distribution of ground deformation. Comparison of ground thermal anomaly clearly delineated the subsidence spots associated with the oxygen supply to combustion areas. On the contrary, few deformations were mapped showing pronounced uplift …

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Genetic Diversity In The Anthracnose Pathogen Infecting Stylosanthes In Brazil, India And China, P. Weeds, S. Chakraborty, Celso D. Fernandes, M. J. Charchar, C. R. Ramesh, Guodao Liu, S. Kelemu Sep 2021

Genetic Diversity In The Anthracnose Pathogen Infecting Stylosanthes In Brazil, India And China, P. Weeds, S. Chakraborty, Celso D. Fernandes, M. J. Charchar, C. R. Ramesh, Guodao Liu, S. Kelemu

IGC Proceedings (1977-2023)

This work aimed to determine the genetic diversity of Colletotrichum gloeosporioides infecting Stylosanthes spp. in Brazil, China and India. A total of 132 isolate originating from S. seabrana, S. macrocephala, S. capitata, S. scabra, and S. guianensis were used. Four major genetic groups were identified from an analysis of genetic diversity using selection-neutral DNA markers. Group 1 contained 20 isolates and this may represent a genotype that migrated from the center of diversity in Brazil and Colombia to Australia, Thailand and India. Group 2 consisted of 66 Brazilian isolates and group 3 had 19 isolates from …

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Relationship Between Tree Density And Grass Dry Matter Yield In A Southern African Savanna, G. N. Smit Sep 2021

Relationship Between Tree Density And Grass Dry Matter Yield In A Southern African Savanna, G. N. Smit

IGC Proceedings (1977-2023)

The investigation was carried out on a densely wooded area in the Mopani savanna of South Africa. Seven plots were subjected to different intensities of tree thinning, ranging from a totally cleared plot (0 %) to plots thinned to the equivalent of 10 %, 20 %, 35 %, 50 % and 75 % of the leaf biomass of a control plot (100 %). The grasses responded positively to the tree thinning in terms of total dry matter yield. The yields between tree canopies were generally of the same order or higher than under tree canopies, with the yields where trees …

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Seasonal Patterns Of Growth And Senescence In Cynodon Spp. Cv Tifton 85 Grazed Swards, L. F. M. Pinto, L. G. Barioni, S. C. Da Silva Sep 2021

Seasonal Patterns Of Growth And Senescence In Cynodon Spp. Cv Tifton 85 Grazed Swards, L. F. M. Pinto, L. G. Barioni, S. C. Da Silva

IGC Proceedings (1977-2023)

Growth and senescence are very important determinants of grassland productivity and correspond to key features to be considered for grazing management purposes. The present study was carried out at ESALQ, Piracicaba, S.P., Brazil and evaluated growth and senescence as a function of sward surface height. Mathematical models generated revealed that a similar pattern of response occurred as described in the literature for temperate grass species. However, a seasonal variation in response curves for growth and senescence was also observed and could be related to climatic events. Highest herbage accumulation rates were observed within the range of 15 to 20 cm …

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Yields And Sward Characteristics Of Timothy Cultivars Under Grazing, H. T. Kunelius, G. H. Dürr, K. B. Mcrae, S. A. E. Fillmore Sep 2021

Yields And Sward Characteristics Of Timothy Cultivars Under Grazing, H. T. Kunelius, G. H. Dürr, K. B. Mcrae, S. A. E. Fillmore

IGC Proceedings (1977-2023)

Seven timothy (Phleum pratense L.) cultivars were evaluated over three pasture seasons under rotational grazing to 7 or 11 cm post-grazing heights and regrowth periods of four to seven weeks. There was a trend for the pasture type timothy cultivars to outyield Champ timothy (check). Dry matter yields were lower for the 7 cm than 11 cm post-grazing height. Although the overall cultivar x post-grazing height interaction was not significant (P > 0.05), there was variability in grazing tolerance among timothy cultivars. Yield of Kahu was maintained and vegetative tiller density of Kahu increased over the experimental period under 7 …

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A Technique For Assessing Seed Survival Of New Pasture Legumes Following Grazing By Sheep, Caroline T. De Koning, P. E. Beale, A. J. Duncan, S. Hughes, K. Haskard Sep 2021

A Technique For Assessing Seed Survival Of New Pasture Legumes Following Grazing By Sheep, Caroline T. De Koning, P. E. Beale, A. J. Duncan, S. Hughes, K. Haskard

IGC Proceedings (1977-2023)

A technique for assessing the fate of seed grazed by sheep in small field plots was examined using the pasture species Trifolium michelianum cv. Paradana, Medicago truncatula cv. Mogul, Trifolium spumosum and Trigonella balansae. Trifolium spumosum lost the greatest proportion of seed from dry pasture residues (88% seed eaten), whereas Trigonella balansae, Paradana and Mogul lost 61%, 55% and 53% respectively. However, Trifolium spumosum and Paradana had high levels of seed in the faeces (56.8 kg/ha and 65.2 kg/ha respectively), whereas Mogul and Trigonella balansae had low levels (10.3 kg/ha and 11.0 kg/ha respectively). Mogul, due to it's …

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Mgrre_Pureoilscouttickets_Vanderwaal_1_21127006310000, Mgrre Sep 2021

Mgrre_Pureoilscouttickets_Vanderwaal_1_21127006310000, Mgrre

Legacy Scout Tickets from Pure Oil Company

No abstract provided.

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Strong Inclination Pacing Of Climate In Late Triassic Low Latitudes Revealed By The Earth-Saturn Tilt Cycle, Miranda Margulis-Ohnuma, Jessica Whiteside, Paul Olsen Sep 2021

Strong Inclination Pacing Of Climate In Late Triassic Low Latitudes Revealed By The Earth-Saturn Tilt Cycle, Miranda Margulis-Ohnuma, Jessica Whiteside, Paul Olsen

The Yale Undergraduate Research Journal

Gravitational interactions among masses in the solar system are recorded in Earth’s paleoclimate history because variations in the geometry of Earth’s orbit and axial orientation modulate insolation. However, astronomical models are unreliable before ~50 Ma due to the chaotic nature of the solar system and therefore must be constrained using geological observations. Here, we use environmental proxies from paleo-tropical Late Triassic lake deposits of the Newark Rift Basin to identify and tune to previously undescribed strong variations in orbital inclination. Tuning to the 173 kyr Earth-Saturn inclination cycle, theoretically stable due to the high mass of Saturn, reveals both other …

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A Dispersive Force Model Of Caribbean Island Biogeography, Anthony Sarkiss Sep 2021

A Dispersive Force Model Of Caribbean Island Biogeography, Anthony Sarkiss

The Yale Undergraduate Research Journal

Framework-based models serve as an important tool to describe, predict and manage ecological systems. In this paper I construct one such model, a dispersive force model based on MacArthur and Wilson’s (1963) theory of island biogeography, in order to assess island species richness with varying climatic patterns. Specifically, I use island–mainland distance (d), insular area (A), a climatic dispersal parameter (f), and a climatic disturbance parameter (h) to calculate the insular species richness ratio at equilibrium. To test this model through hurricane impact on marine islands, it was executed with data from islands of the Dutch Caribbean. Future climatic conditions …

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Seasonal Growth Curves Of Perennial Ryegrass In Mexico, M. E. Z. Velasco, Alfonso Hernández-Garay, J. P. Pérez, V. A. González-Hernández Sep 2021

Seasonal Growth Curves Of Perennial Ryegrass In Mexico, M. E. Z. Velasco, Alfonso Hernández-Garay, J. P. Pérez, V. A. González-Hernández

IGC Proceedings (1977-2023)

An experiment was established at Colegio de Postgraduados Research Station, Texcoco, México to evaluate the seasonal pattern of growth curve of perennial ryegrass (Lolium perenne) swards. Growth rate increases rapidly from a low level immediately after defoliation, and eventually reaches an equilibrium level as the amount of green leaf in the sward stabilize. The time required to reach this state varied according to the season of year, with the four seasons ranked in the order: spring (4 weeks) < summer (5 weeks) < autumn and winter (6 weeks). Once swards reached equilibrium, growth rates started to decline as a consequence of an increase in dead material and pseudostem. These increases were highest in spring and lowest in winter. The results of this study suggest that sward management to maximise herbage production and utilisation in ryegrass swards must be done once the highest green leaf mass is reached. In this trial, it was reached at 5, 6, 6 and 4 weeks in summer, autumn, winter and spring, respectively.

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The Effects Of Planting Density On The Dry Matter Yield And The Overwintering Ability Of The Dwarf And Normal Napiergrasses In Two Years After Planting, Yasuyuki Ishii, M. M. Mukhtar, Sayan Tudsri Sep 2021

The Effects Of Planting Density On The Dry Matter Yield And The Overwintering Ability Of The Dwarf And Normal Napiergrasses In Two Years After Planting, Yasuyuki Ishii, M. M. Mukhtar, Sayan Tudsri

IGC Proceedings (1977-2023)

The objective of this study is to determine the optimum planting density in napiergrass (Pennisetum purpureum Schumach) among two dwarf varieties introduced from Thailand and two normal ones under three levels of density. Dwarf varieties showed lower plant height and mean tiller weight, and higher leaf area index (LAI) and leaf blade percentage. Crop growth rate was positively correlated with LAI, and net assimilation rate and canopy extinction coefficient (K) were negatively correlated with LAI in the second year, including all dwarf and normal varieties, while K tended to be lower in the dwarf varieties. With the increase in …

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Light Interception And Dry Matter Yield In Grass/Legume Mixtures, H. A. Jönsson Sep 2021

Light Interception And Dry Matter Yield In Grass/Legume Mixtures, H. A. Jönsson

IGC Proceedings (1977-2023)

The influence of grass variety on light interception and dry matter yield in a grass/clover mixture was studied. Two varieties of timothy (Phleum pratense L.) and five varieties of ryegrass (Lolium spp) as components in a mixture were compared during the spring period up to the first cut of the third harvest year. By replacing the timothy variety in the mixture both light interception and dry matter yield were significantly affected. The leaf orientation was thought to be a contributing factor with erect leaves intercepting less light. There were no significant differences neither in light interception nor …

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Photosynthetic Light Response Of Tanzania Grass Under Four Levels Of Leaf Temperature, A. C. L. De Mello, P. M. Santos, Carlos G. S. Pedreira, M. Corsi, C. T. Dos S. Dias Sep 2021

Photosynthetic Light Response Of Tanzania Grass Under Four Levels Of Leaf Temperature, A. C. L. De Mello, P. M. Santos, Carlos G. S. Pedreira, M. Corsi, C. T. Dos S. Dias

IGC Proceedings (1977-2023)

The purpose of this paper is to establish photosynthetic light response curves for Tanzania grass (Panicum maximum Jacq.) under four leaf temperature levels. Photosynthetic rate was measured as a response to levels of photosynthetic photon flux density (PPFD) on the youngest fully expanded leaves of 12 representative tillers with an infra red gas analyzer. The effect of PPFD was tested for each leaf temperature level in a randomized complete block design. Photosynthetic light response curves were adjusted for each leaf temperature using a non-linear hyperbolic model. The maximum photosynthetic response was 25,59; 31,43; 34,57 and 27,53 µmol CO2 …

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Nonstructural Carbohydrate Reserves Of Temperate Perennial Grasses In Autumn Early Growth, Y. Tamura, K. Matoba, A. Fushimi, M. Moriyama Sep 2021

Nonstructural Carbohydrate Reserves Of Temperate Perennial Grasses In Autumn Early Growth, Y. Tamura, K. Matoba, A. Fushimi, M. Moriyama

IGC Proceedings (1977-2023)

The objective of this study was to determine levels of nonstructural carbohydrate reserves of four temperate perennial grasses: Orchardgrass (Dactylis glomerata L.), Timothy (Phleum pratense L.), Perennial ryegrass (Lolium perenne L.), and Reed canarygrass (Phalaris arundinacea L.) in their early growth stages during the cool autumn temperatures in northern Japan. At the time of sampling, all grasses were in their vegetative stage, and Reed canarygrass was not forming rhizomes. Fructosan concentration in reed canarygrass roots (8.04%) was 22 times that of the leaf blade (0.36%) and twice that of the stem (3.40%); the concentration in reed …

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Mgrre_Pureoilscouttickets_Cushing, W. F._1_Na, Mgrre Sep 2021

Mgrre_Pureoilscouttickets_Cushing, W. F._1_Na, Mgrre

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No abstract provided.

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Effect Of Cutting Height On Tiller Population Density And Herbage Biomass Of Buffel Grass, L. S. Beltrán, P. J. Pérez, G. A. Hernández, M. E. García, S. J. Kohashi, H. J. G. Herrera Sep 2021

Effect Of Cutting Height On Tiller Population Density And Herbage Biomass Of Buffel Grass, L. S. Beltrán, P. J. Pérez, G. A. Hernández, M. E. García, S. J. Kohashi, H. J. G. Herrera

IGC Proceedings (1977-2023)

The aim of this trial was to investigate the effect of different cutting heights on tiller population density and herbage biomass of Buffel grass (Cenchrus ciliaris L) grown in miniature swards in a greenhouse. Four treatments with five replicates: five cm, ten cm, and 20 cm cutting height, and control (without cut) were randomly allocated. Intensity of defoliation affected the cumulative herbage harvested; the ten cm cutting height was greater (404.1 g DM m-2) than 5 cm (317.6 g DM m-2) and 20 cm (263.9 g DM m-2), respectively. Cumulative herbage harvested in …

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Leaf Appearance Rate In Brachiaria Decumbens Grown In Nitrogen And Potassium Rates, M. D. C. Ferragine, F. A. Monteiro, S. C. Da Silva Sep 2021

Leaf Appearance Rate In Brachiaria Decumbens Grown In Nitrogen And Potassium Rates, M. D. C. Ferragine, F. A. Monteiro, S. C. Da Silva

IGC Proceedings (1977-2023)

A greenhouse experiment was carried out with Brachiaria decumbens Stapf. cv. Basilisk grown in nutrient solution. Five nitrogen rates (42; 140; 238; 336 and 434 mg/L) and three potassium rates (78; 234 and 390 mg/L) were studied in a factorial experiment, in a randomized complete block design, with four replications. Green leaf number was evaluated in six times in the first period of growth (27, 30, 33, 36, 39 and 42 days after transplanting) and nine times in the second period (45, 48, 51, 54, 57, 60, 63, 66 and 69 days after transplanting). Data was registered in three plants …

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Morphogenesis And Defoliation Frequency Of Italian Ryegrass (Lolium Multiflorum) And Paspalum Urvillei In Lowland Under Three Levels Of P And K, Fernando L. F. De Quadros, A. G. S. Pigatto, D. G. Bandinelli, E. Marchezan, Marta G. Da Rocha Sep 2021

Morphogenesis And Defoliation Frequency Of Italian Ryegrass (Lolium Multiflorum) And Paspalum Urvillei In Lowland Under Three Levels Of P And K, Fernando L. F. De Quadros, A. G. S. Pigatto, D. G. Bandinelli, E. Marchezan, Marta G. Da Rocha

IGC Proceedings (1977-2023)

This trial was conducted to evaluate growth dynamics and defoliation frequency of Italian ryegrass (Lolium multiflorum) and Paspalum urvillei in a lowland area under three levels of P and K. Using randomization tests we observed that, in a general way, fertilizer treatments were not the determinant factors of leaf appearance and elongation rates for both species. Only the leaf appearance rate of Paspalum urvillei at 100 % of recommendation level and the elongation rate for Italian ryegrass, in the same treatment, was different. Probably other factors, like drainage, are contributing to these results. I. ryegrass phyllochron ranged from …

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Variability In Herbage Mass And Chemical Composition Within A Timothy Sward, O. Niemeläinen, E. Miettinen, P. Virkajärvi, L. Alakukku, K. Hakala Sep 2021

Variability In Herbage Mass And Chemical Composition Within A Timothy Sward, O. Niemeläinen, E. Miettinen, P. Virkajärvi, L. Alakukku, K. Hakala

IGC Proceedings (1977-2023)

Variability in herbage mass (HM) and chemical composition of timothy (Phleum pratense L.) sward was studied in a three-hectare field. The field, which was flat, was divided into twelve sections and a sampling site was randomly selected in each. The study was carried out in Sotkamo (64o 01’N, 28o22’E) research station in Finland. Snow depth and frost conditions were measured in winter and soil water content was monitored in the growing season at each sampling site. Observations on the crop included assessment of herbage ground cover and winter damage percentage, stand height and HM and analysis …

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Effects Of Temperature, Nitrogen Fertilisation And Leaf And Tiller Age On Specific Leaf Area Of Brachiaria Decumbens, J. Busqué, M. Herrero Sep 2021

Effects Of Temperature, Nitrogen Fertilisation And Leaf And Tiller Age On Specific Leaf Area Of Brachiaria Decumbens, J. Busqué, M. Herrero

IGC Proceedings (1977-2023)

Signal grass (Brachiaria decumbens Stapf) micro-swards were grown under controlled environmental conditions at different temperatures and nitrogen fertilisation rates. Specific leaf area was responsive both to temperature and nitrogen, but did not change with the level of insertion of the leaf in the tiller. Senescing leaves had higher specific leaf area than old extended green leaves and these had higher values than new extended green leaves. Changes in specific leaf area were more related to changes in leaf area and more exactly to changes in leaf width.

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