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2024

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Articles 121 - 150 of 7799

Full-Text Articles in Physical Sciences and Mathematics

Intake Of South African Mutton Merino Ewes On Wheat Stubble Grazing, T S. Brand, J M. Van Heerden, F Franck Sep 2024

Intake Of South African Mutton Merino Ewes On Wheat Stubble Grazing, T S. Brand, J M. Van Heerden, F Franck

IGC Proceedings (1993-2023)

Wheat stubble was grazed continuously for 154 days during the summer (December-April) by reproducing and dry ewes (n-8) at 2 stocking rates ( 1 or 2 ewes/ha), Samples were collected for chemical analysis from oesophageally fistulated (OF) sheep. Intake was determined using controlled chromium-release devices. The mean CP, ADF and NDF contents and iii vitro OM digestibility of samples were respectively 16.1:t0.4%; 40.7:t0.8%, 59.0:tl.1% and 48.5±0.7% t 1 ewe/ha and 10.8±1.1%; 53.9±1.1%, 72.1±0.9% and 48.8:t0.7% at 2 ewes/ha. The mean CP intake of dry ewes was 202±7 g/day (I ewe/ha) and 113:t6 g/day (2 ewes/ha), while the CP intake of …

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Earthworms In Pastoral Soils Of Northland, New Zealand, P W. Woods, A.R J. Christie, J N. Couchman Sep 2024

Earthworms In Pastoral Soils Of Northland, New Zealand, P W. Woods, A.R J. Christie, J N. Couchman

IGC Proceedings (1993-2023)

Earthworm populations were surveyed in 4S pastures in Northland, New Zealand. Both sheep and beef, and dairying properties were sampled during late winter. European liumbricid earthworm species encountered were Aporrectodea caliginosa, A. trapezoides, A. rosea, A. longa, Lumbricus rubellus, L. terrestris, L. castaneus and Octolasion cyaneum. Amynthas diffringens, a megascolecid of Asian origin, was also found. Three native megascolecid species were found under developed pasture. Shallow burrowing species such as Lumbricus rubellus and A. caliginosa were the most frequently encountered species, being present on 91% and 89% of sites, respectively. A. caliginosa was the main contributor to earthworm biomass. …

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First Results On Growth Rates Of The Endophytic Fungi Acremonium And Epichloe On Solid And Liquid Media, P Dapprich, A Klose, V H. Paul Sep 2024

First Results On Growth Rates Of The Endophytic Fungi Acremonium And Epichloe On Solid And Liquid Media, P Dapprich, A Klose, V H. Paul

IGC Proceedings (1993-2023)

Growth rates of the ·grass endophytes Acrenonium lolii Latch, Christensen and Samuels, A. coenoplrialiim Morgan-Jones lind Garns and Epichloe typhina' (Fries) Tulasne were measured on different solid media under various conditions and in liquid medium. A. coenophiallum and E. ryphina developed best vegetative growth at 25°C in the dark ori;pofato-dextrose-ilgar (PDA) and on minimal­medium (MM), respectively. A: lo/ii grew best at 2coenophialum and E. typhina produced 1.48 g and 6 g FW, respectively. Within 3 days the conductivit)'. reached constant values.· Osmolarity decreased with the increase of biomass. pH rose in cultures of A. lolii and E. typhina …

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Discovery Of Gynaephora Ruoergensis Nuclear Polyhedrosis Virus (Grnpv) And Its Use As A Baculovirus Pesticide In Qinghai-Tibet Plateau, Liu Shigui, Yang Zhirong, Wu Tieqiao, Zeng Ying, Cheng Shuqiu Sep 2024

Discovery Of Gynaephora Ruoergensis Nuclear Polyhedrosis Virus (Grnpv) And Its Use As A Baculovirus Pesticide In Qinghai-Tibet Plateau, Liu Shigui, Yang Zhirong, Wu Tieqiao, Zeng Ying, Cheng Shuqiu

IGC Proceedings (1993-2023)

A new pathogenic virus agent was isolated from the grassland caterpillar Gynaephora rnoergensis, an important pest of grassland in north-western Sichuan. Identification was based on morphological properties, biological characteristics and biochemical studies. It belongs to Subgroup A of the Baculoviridae, and has been named Gynaephora rnoergensis nuclear polyhedrosis virus (GrNPV). A viral pesticide was prepared using GrNPV. It has a killing efficiency of mote than 84.3% to grassland caterpillars, and has been applied for biological control of the pest to 2.3 million ha of grassland in north we􀁏tern Sichuan grassland and the Qinghai-Tibet,plateau.

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Infection By Bdellovibrio Bacteriovirus Of Leguminous Forage Rhizobia, Xu Heng, Liu Shigui Sep 2024

Infection By Bdellovibrio Bacteriovirus Of Leguminous Forage Rhizobia, Xu Heng, Liu Shigui

IGC Proceedings (1993-2023)

Two bdellovibrio bacteriovirus infecting rhizobia of leguminous forage were isolated from Sichuan-Tibet plateau grassland. The culture characteristics, host range and other biological properties of two bdellovibrio bacterioviruses were researched. Research indicated that the two bdellovibrio bacterioviruses had a wide host range and a strong lyslng ability with Rhlwbium melilotl, R. trlfolll and R, astragalll. 8dellovibrio bacterioviruses affected nodu lation of leguminous forages in grassland, and are one of the main biological factors that lower the yield of leguminous forages.

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Studies On The Mutagenicity Of Gynaephora Ruoergensis Nuclear Polyhedrosis Virus (Grnpv), A New Biological Pesticide, Liu Shigui, Wu Yong, Zeng Ying, Wu Tieqiao, Yang Zhirong Sep 2024

Studies On The Mutagenicity Of Gynaephora Ruoergensis Nuclear Polyhedrosis Virus (Grnpv), A New Biological Pesticide, Liu Shigui, Wu Yong, Zeng Ying, Wu Tieqiao, Yang Zhirong

IGC Proceedings (1993-2023)

To test pathogenicity and mutagenicity of Gynaepllora ruoergensis nuclear polyhedrosis virus (GrNPV), a new biological pesticide, acute and subacute infection tests were carried out in 366 vertebrates (16 species). Results indicated that GrNPV has no toxicity to vertebrates. No mutagenicity to Salmonela. typhimium . was found using the Ames.test. Four tests using cytogenelic methods, sister chromosome exchange (SCB), chromosome aberration test, a micro-nuclear test of mouse eosinophH cells, and lethal effect tests, indicated no mutagenictic effects to vertebrates.

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Survey For Natural Enemies Of Leafy Spurge Of Rangeland In Northern China, Wang Jian Feng Sep 2024

Survey For Natural Enemies Of Leafy Spurge Of Rangeland In Northern China, Wang Jian Feng

IGC Proceedings (1993-2023)

Leafy spurge (Euphorbia esula L,) is a serious. toxic weed in the real Plains region of lhe USA and Canada where it is toxic to s9me; classes of livestock and displaces more desirable forage plants. Leafy spurge is also spreading widely in Inner Mongolia rangeland, but it does limited damage. Biological weed control scientists from China, USA and Canada have co-operated in a survey for natural enemies of leafy spurge.in Innc Mongolia rangeland where there is an abundant diverse assemblage of insects and pathogens , including: Aphthona , chln ch ichi, Apthona s.eriata, Oberea prob . erythrocephala, Chamaespecia sp. …

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A Method For The Greenhouse Evaluation Of Subterranean Clover Breeding Lines For Phytophthora Clandestina Root Rot, S P. Flett, P A. Taylor, V Wakley Sep 2024

A Method For The Greenhouse Evaluation Of Subterranean Clover Breeding Lines For Phytophthora Clandestina Root Rot, S P. Flett, P A. Taylor, V Wakley

IGC Proceedings (1993-2023)

Subterranean clover root rot, caused by Phytophthora clandestina, is a serious disease in both irrigated and dryland pastoral regions of Australia. An Intensive program of screening cultivars and genetic lines of subterranean clover from the National Subterranean Clover Improvement Program (NSCIP) for resistance to root rot caused by Phytophthora clandestina is described, Subterranean clover (Trifolium subterraneum L.) lines, divided into screening runs, were infected with isolates of P. clandestina in a cooled greenhouse and each run required 11 weeks for complete evaluation, Each line was rated for root rot resistance ogainst a standard resistant cv. Larisa and a …

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Enhancing Dtc Control Of Im Using Fuzzy Logic And Three-Level Inverter: A Comparative Study, Siham Mencou, Majid Benyakhlef, Elbachir Tazi Sep 2024

Enhancing Dtc Control Of Im Using Fuzzy Logic And Three-Level Inverter: A Comparative Study, Siham Mencou, Majid Benyakhlef, Elbachir Tazi

Turkish Journal of Electrical Engineering and Computer Sciences

Direct torque control is the most appropriate strategy for induction motor drive systems, due to its considerable ability to reduce the impact of of machine parameter variations, while offering fast dynamic response and simplified control implementation. However, persistent problems associated with high torque ripple and variable switching frequencies prevent its widespread adoption. To overcome these limitations, several techniques have been developed, in particular the use of multi-level inverters and fuzzy logic algorithms. This article proposes an in-depth evaluation of these techniques in a MATALB/Simulink environment, under various operational conditions. The main objective is to provide a detailed performance analysis of …

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Re: Comment Letter For Draft Bpsou 2023 Groundwater Data Summary Report (Dated May 31, 2024), Emma Rott Sep 2024

Re: Comment Letter For Draft Bpsou 2023 Groundwater Data Summary Report (Dated May 31, 2024), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Power Quality Enhancement In Hybrid Pv-Bes System Based On Ann-Mppt, Heli̇n Bozkurt, Özgür Çeli̇k, Ahmet Teke Sep 2024

Power Quality Enhancement In Hybrid Pv-Bes System Based On Ann-Mppt, Heli̇n Bozkurt, Özgür Çeli̇k, Ahmet Teke

Turkish Journal of Electrical Engineering and Computer Sciences

Battery energy systems (BESs) assisted photovoltaic (PV) plants are among the popular hybrid power systems in terms of energy efficiency, energy management, uninterrupted power supply, grid-connected and off-grid availability. The primary objective of this study is to enhance the power quality of a grid-tied PV-BES hybrid system by developing an operation strategy based on Artificial Neural Network (ANN) based maximum power point tracking (MPPT) method. A test system comprising a 10-kWh BES and a 12.4 kW PV plant is structured and simulated on the MATLAB/Simulink platform. The hybrid system is validated with three different cases: constant radiation, rapid changing radiation, …

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Finger Movement Recognition Using Machine Learning Algorithms With Tree-Seed Algorithm, Muhammed Sami̇ Karakul, Ahmet Gökçen Sep 2024

Finger Movement Recognition Using Machine Learning Algorithms With Tree-Seed Algorithm, Muhammed Sami̇ Karakul, Ahmet Gökçen

Turkish Journal of Electrical Engineering and Computer Sciences

Electromyography (EMG) signals have been used to recognize various actions of hand movements, finger movements, and hand gestures. This paper aims to improve the classification accuracy of EMG signals while decreasing the number of features using the Tree-Seed Algorithm. The dataset containing EMG signals utilized in this investigation is derived from a publicly accessible source. The rationale for selecting the Tree-Seed Algorithm centers on its ability to enhance classification accuracy while minimizing the dimensionality of feature sets. The object function and Tree-Seed Algorithm's nature avoids the results to have low accuracy with fewer features. The aim is not just to …

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Mention Detection In Turkish Coreference Resolution, Şeni̇z Demi̇r, Hani̇fi̇ İbrahi̇m Akdağ Sep 2024

Mention Detection In Turkish Coreference Resolution, Şeni̇z Demi̇r, Hani̇fi̇ İbrahi̇m Akdağ

Turkish Journal of Electrical Engineering and Computer Sciences

A crucial step in understanding natural language is detecting mentions that refer to real-world entities in a text and correctly identifying their boundaries. Mention detection is commonly considered a preprocessing step in coreference resolution which is shown to be helpful in several language processing applications such as machine translation and text summarization. Despite recent efforts on Turkish coreference resolution, no standalone neural solution to mention detection has been proposed yet. In this article, we present two models designed for detecting Turkish mentions by using feed-forward neural networks. Both models extract all spans up to a fixed length from input text …

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A Single Operational Amplifier-Based Grounded Meminductor Mutators And Their Applications, Shalini Gupta, Kunwar Singh, Shireesh Kumar Rai Sep 2024

A Single Operational Amplifier-Based Grounded Meminductor Mutators And Their Applications, Shalini Gupta, Kunwar Singh, Shireesh Kumar Rai

Turkish Journal of Electrical Engineering and Computer Sciences

In this work, three simple configurations of meminductor mutator are presented. The first two configurations of meminductor mutator have been implemented utilizing one CMOS-based operational amplifier, one memristor, one capacitor, and five resistors, while the third configuration of meminductor mutator is implemented utilizing one CMOS based operational amplifier, two memristors, one capacitor, and four resistors. The implementation and simulation of the proposed configurations are done by using LTspice tool. The viability of the proposed circuits is demonstrated by utilizing TSMC 180 nm CMOS technology parameters. The proposed circuits of the meminductor have a simple structure in contrast to many of …

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Recent Climate Change In Utah, 1870-2023, Scott Hotaling, Kendall Becker Sep 2024

Recent Climate Change In Utah, 1870-2023, Scott Hotaling, Kendall Becker

All Current Publications

Climate change is impacting Utah. Forty-five years of temperature data show that Utah is steadily warming, which, in turn, is driving declines in winter snowpack, shifting the timing and amount of available water, increasing fire risk, and causing ecological change. This fact sheet addresses changes in Utah's temperature, precipitation and snowpack, streamflow, wildfire, and ecology.

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Optimizing Neural Network Architecture Using Kernel Principal Component Analysis, Saige Simcox Sep 2024

Optimizing Neural Network Architecture Using Kernel Principal Component Analysis, Saige Simcox

Theses and Dissertations

Neural networks have proven to be powerful tools for modeling a wide range of problems across applications. However, one of the challenges in implementing a neural network model lies in determining the neural network architecture, i.e. the appropriate number of hidden layers and the number of neurons per hidden layer. It has been suggested that one way to determine the number of hidden layers is by using information on the variability captured by each principal component. In this research, we expand on this idea and propose a new approach to determine the neural network architecture for a multilayer perceptron used …

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A Generalized Machine Learning Model For Long-Term Coral Reef Monitoring In The Red Sea, Justin J. Gapper, Surendra Maharjan, Wenzhao Li, Erik Linstead, Surya Prakash Tiwari, Mohamed A. Qurban, Hesham El-Askary Sep 2024

A Generalized Machine Learning Model For Long-Term Coral Reef Monitoring In The Red Sea, Justin J. Gapper, Surendra Maharjan, Wenzhao Li, Erik Linstead, Surya Prakash Tiwari, Mohamed A. Qurban, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Coral reefs, despite covering less than 0.2 % of the ocean floor, harbor approximately 35 % of all known marine species, making their conservation critical. However, coral bleaching, exacerbated by climate change and phenomena such as El Niño, poses a significant threat to these ecosystems. This study focuses on the Red Sea, proposing a generalized machine learning approach to detect and monitor changes in coral reef cover over an 18-year period (2000–2018). Using Landsat 7 and 8 data, a Support Vector Machine (SVM) classifier was trained on depth-invariant indices (DII) derived from the Gulf of Aqaba and validated against ground …

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Prediction Of Mooring System Characteristics Of The Floating Barge Using Deep Neural Networks, Janghoon Seo, Dong-Woo Park Sep 2024

Prediction Of Mooring System Characteristics Of The Floating Barge Using Deep Neural Networks, Janghoon Seo, Dong-Woo Park

Journal of Marine Science and Technology

The present study establishes deep learning models to predict the tensions and inclinations of mooring lines of a floating barge and verifies applicability of these models. Hydrodynamic and mooring analyses are conducted on the dataset used for the deep learning models. Three types of neural network models include a deep neural network (DNN) with input data representing the six degrees of freedom motions of a floating barge, convolutional neural network (CNN) with input images of the floating barge and mooring lines on a horizontal plane, and hybrid neural network (HNN) that consolidates the characteristics of DNN and CNN models. The …

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Variational Bayesian Inference For Functional Data Clustering And Survival Data Analysis, Chengqian Xian Sep 2024

Variational Bayesian Inference For Functional Data Clustering And Survival Data Analysis, Chengqian Xian

Electronic Thesis and Dissertation Repository

Variational Bayesian inference is a method to approximate the posterior distribution under a Bayesian model analytically. As an alternative to Markov Chain Monte Carlo (MCMC) methods, variational inference (VI) produces an analytical solution to an approximation of the posterior but have a lower computational cost compared to MCMC methods. The main challenge of applying VI comes from deriving the equations used to update the approximated posterior parameters iteratively, especially when dealing with complex data. In this thesis, we apply the VI to the context of functional data clustering and survival data analysis. The main objective is to develop novel VI …

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Monthly Changes In Plant Biomass, Net Primary Productivity And Transfer Dynamics Of A Tropical Grazing Land Ecosystem In Southern India, K.S T.K Karuniachamy, K Paliwal Sep 2024

Monthly Changes In Plant Biomass, Net Primary Productivity And Transfer Dynamics Of A Tropical Grazing Land Ecosystem In Southern India, K.S T.K Karuniachamy, K Paliwal

IGC Proceedings (1993-2023)

Monthly changes in plant biomass, net primary productivity and transfer dynamics of tropical grazing land of western Ghats region, southern India, are presented. The annual above- ground net production was 9.03 g/m2/day and the below-ground net production was 2.56 g/m2/day. Total annual net primary production was estimated at 4232 g/m2/day. Of the total input of 11.59 g/m2/day into the system, about 77.9% was channelled to above-ground and 22.1% to below­ground, The rate of litter disappearance was 0.55 g/m2/day and l.14 g/ m2/day for below-ground disappearance. The total output was 1.69 g/ m2/day which was 14.6% of the total input. Thus, …

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Photosynthesis And Water Relations Of Two Savanna Grasses As Influenced By Shade And Water Stress, M J. Trlica, J I. Kinyamario Sep 2024

Photosynthesis And Water Relations Of Two Savanna Grasses As Influenced By Shade And Water Stress, M J. Trlica, J I. Kinyamario

IGC Proceedings (1993-2023)

Net CO2 assimilation and plant water relations of the African savanna grasses Panicum maximum Jacq. and Tliemeda triandra Porrsk. were measured under controlled conditions. We hypothesised that 1; triandra would be better adapted to higher light and temperature conditions and could withstand greater moisture stress than could P. maximum, as T. tria11dra is commonly found in open areas, whereas P. maximum dominates in the shade of trees. Plants of both species were transplanted into a common soil in large pots and placed under shade (approximately 150 µrnoVm1/s photon flux density (PFD)) or high light (approximately 1200 µmoVm1/s PFD) conditions, with …

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Grazing Management Effects On Diverse White Clover Cultivars, G E. Brink, G A. Pederson Sep 2024

Grazing Management Effects On Diverse White Clover Cultivars, G E. Brink, G A. Pederson

IGC Proceedings (1993-2023)

Tall fescue (Festuca arundinacea Schreb.) was oversewn with Grasslands Huia, Louisiana S-1, and Regal white clover (Trifolimn repens L.) and stocked the following year continuously or rotationally with cattle to detennine cultivar response to grazing method. When precipitation was 59% above normal, mean leaf area, forage and stolon dry weight, and stolon growing point density in June and August were unaffected by grazing method. These parameters were reduced under continuous stocking when precipitation was 32% below normal. Cultivar ranking for mean leaf area and petiole length was the same as that for leaf size: Grasslands Huin

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Determination Of Nitrogen Sources (Mineral, Atmospheric Or Endogenous) Used By Lucerne During Regrowth, K Tae Hwan, A Ourry, G Lemaire, J Boucaud Sep 2024

Determination Of Nitrogen Sources (Mineral, Atmospheric Or Endogenous) Used By Lucerne During Regrowth, K Tae Hwan, A Ourry, G Lemaire, J Boucaud

IGC Proceedings (1993-2023)

Although for forage legumes such as Medicago saliva, ii is established that nitrogenase activity is very low during the 2 fust weeks of regrowth, there are no data on the amount d nitrogen in regrowin g shoots derived from N1 fixation. In order to ascertain the orisin of N used for regrowth of lucerne, several experiments were unde,taken usin g 15N labellin g to distinguish between endogenous, mineral and atmospheric N recovered' in regrowing shoots of nodulated or non-nodulated lucerne. Calculation of N fluxes from ISN data showed that both N uptake from the medium and N2 fixation strongly decreased …

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Varietal Differences In Brassica Fodder As Affected By Nitrogen Topdressing And Seeding Date, S H. Moon, H Hirota Sep 2024

Varietal Differences In Brassica Fodder As Affected By Nitrogen Topdressing And Seeding Date, S H. Moon, H Hirota

IGC Proceedings (1993-2023)

Two experiments were carried out both in spring and fall with cultivars of rape (Brassica napus spp.) and C.O. (B. campestris x B. oleracea). Both cullivars showed lillle increase in plant length in spring sowing with nitrogen topdressing, but the increments were higher in earlier topdressing (T l) and later topdressing (T2) than in control in autumn sowing, although the difference was not significant. There was no difference in the number of leaves throughout the growing stages between the N topdressing treatments in spring and autumn sowing. Leaf area was greater in Tl and T2 than in control in early …

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Reserve Mobilization During Regrowth After Cutting Of Forage Species: Quantification And Physiological Mechanisms In Ryegrass And Lucerne, A Ourry, J Bigot, T Kim, J Boucaud, J Salette Sep 2024

Reserve Mobilization During Regrowth After Cutting Of Forage Species: Quantification And Physiological Mechanisms In Ryegrass And Lucerne, A Ourry, J Bigot, T Kim, J Boucaud, J Salette

IGC Proceedings (1993-2023)

Time course of remobilisation of reserves was studied during the regrowth of Loli11m perem1e and Medicago sativa by 15N labelling, carbohydrate analyses and by measuring time course of several enzymes activities. When photosynthesis decreased during early regrowth, and consequently reduced availability of carbon skeletons within the plant, both nitrogen (N) uptake (lolium perene) and N2 fixatlon (Medicago saliva) decreased. Nilrogenase, as well as nitrate reductase activities, decreased. Reduction of external N assimilation was compensated for by intensive mobilization of endogenous N in roots of lucerne and in stubble of ryegrass. In the same manner, some of …

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Effect Of Temperature On Nitrogen Fixation Rates In Seven Clover Cultivars, J R. Crush, B D. Campbell, J R. Caradus Sep 2024

Effect Of Temperature On Nitrogen Fixation Rates In Seven Clover Cultivars, J R. Crush, B D. Campbell, J R. Caradus

IGC Proceedings (1993-2023)

Seven white clover (Trifolium repens L) cultivars were grown in growth rooms at S different temperatures between S and 2S°C. Plant growth and nitrogenase activity (acetylene reduction) were measured. There were significant effects of temperature on total plant ay matter (DM) accumulation and nitrogenase activity. Temperature x cultivar interactions were significant for DM accumulation, nitrogenase activity per pot and nitrogenase activity/g DM. There was a strong correlation between DM increment/°C rise in temperature over the range 10-20°C, and nitrogenase activity/g DM. Three cultivars had maximum nitrogenase activity/g plant DM at 200C and 4 cultivars peaked at 15° C. These differences …

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Physiological Characteristics Of Nitrate Uptake By Different Catch Crop Species, P Laine, A Ourry, J Boucaud, J Salette Sep 2024

Physiological Characteristics Of Nitrate Uptake By Different Catch Crop Species, P Laine, A Ourry, J Boucaud, J Salette

IGC Proceedings (1993-2023)

The pollution of aquifers by nitrate is aggravated by farming practices that leave the ground bare during winter. Establishment of catch crops during this time could be suitable farming strategy to decrease nitrate loss from the soil. Only a few studies are available on the physiology of nitrate uptake by these species. Experiments were conducted on Lolium perenne, Secale cereale, Trifolium incarnatum, Trifolirim alexendrnum, Phacelia tanacetifolia, Brassica rapa, Brassica napus, Sinapsis alba and Raphanus sativus grown in hydroponic conditions, in order to investigate the physiological basis of the NO3- uptake system when plants are grown with optimum ocniditons of light, …

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Relationships Between Growth And Carbon Isotope Discrimination For Some Pasture Species, J Virgona Sep 2024

Relationships Between Growth And Carbon Isotope Discrimination For Some Pasture Species, J Virgona

IGC Proceedings (1993-2023)

Carbon isotope discrimination (A) by plants can be directly related to plant water-use efficiency (W, total plant dry matter, OM, per water transpired) and used in selection to achieve greater W. As \V (and A) is a complex characteristic, there maybe inherent relationships between it and plant productivity. A range of pasture cultivars (of temperate grasses and legumes) were grown in pots (lo c. 50 days) and \V, A and total dry mailer measured. Among cultivars the relationship between W and A was negative and significant as was the relationship between A and total OM accumulation. A further experiment showed …

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Acquisition And Allocation Of Phosphorus In A Population Of White Clover Plants In A Rotationally Grazed Pasture, M.J M. Hay, D F. Chapman Sep 2024

Acquisition And Allocation Of Phosphorus In A Population Of White Clover Plants In A Rotationally Grazed Pasture, M.J M. Hay, D F. Chapman

IGC Proceedings (1993-2023)

This paper quantifies the processes of acquisition, allocation and retranslocation of phosphorus (P) within a white clover (Trifolium repens L.) population in a mixed grass-clover pasture during a regrowth period in early winter (13 May-8 July 1991). The work described is part of a broader study examining seasonal variation in these processes. The data allows an analysis of the changing P economy of plants and of whole populations. White clover plants were grouped by !heir hierarchy of branching. Within plants, stolons were grouped by order of branching, dissected into leaf, stolon and root, oven-dried, weighed and analysed for P …

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Defoliation Of Young Branch And Parent Stolons Of White Clover In Rotationally Grazed Pastures, M.J M. Hay, M Kim, R W. Mclean, A Gonzalez-Rodriguez Sep 2024

Defoliation Of Young Branch And Parent Stolons Of White Clover In Rotationally Grazed Pastures, M.J M. Hay, M Kim, R W. Mclean, A Gonzalez-Rodriguez

IGC Proceedings (1993-2023)

This study was undertaken to examine the relative severity of defoliation of young branches (those comprising <4 nodes) and parent stolons of white clover (Trifolium repens L.) in rotationally grazed pastures stocked al either 2.5, 5.0 or 7.5 bulls/ha. On 7 occasions over a year, the defoliation of expanded leaves of parenl and branch stolons was assessed using tagged stolons. Petiole length of leaves ,vas measured before grazing. Leaves of young branch stolons (43% of the total number of leaves defoliated) were less severely defoliated than leaves of parent stolons (64%). Defoliation of branch stolon leaves was relatively greater at the higher stocking rates which had lower residual …

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