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Full-Text Articles in Life Sciences

Assessing The Impact Of Dietary Addition Of Lignin On Growth Performance, Nitrogen Balance And Faecal Microorganisms In Grain-Fed Veal Calves, L E. Phillip, E S. Idziak Jun 2024

Assessing The Impact Of Dietary Addition Of Lignin On Growth Performance, Nitrogen Balance And Faecal Microorganisms In Grain-Fed Veal Calves, L E. Phillip, E S. Idziak

IGC Proceedings (1997-2023)

A study was conducted with ALCELLR - lignin (A-lignin) to evaluate its impact on performance of grain- fed veal calves. Thirty two male calves (avg. initial wt, 190 kg) were fed for 13 weeks grain corn and a protein supplement with added A-lignin to supply 0, 1.25%, 2.5% or 5.0% of diet. Eight other calves were used to study nitrogen balance, and grab samples of faeces were analyzed for anaerobic, aerobic and coliform bacteria. A-lignin at 1.25% of diet increased (p<.01) weight gain by 12%. Addition of A-lignin also decreased (p< 0.01) organic matter digestion, increased (p<.01) faecal N excretion but did not significantly alter N balance. A-lignin reduced (p< 0.01) faecal ammonia concentration but increased (p <.01) DM content of grab samples of faeces; there were no significant effects on populations of faecal microorganisms. The study revealed a beneficial effect of A-lignin on calf growth but the reason for the response was not uncovered.


Morphological Development Rates Of Perennial Forage Grasses, R B. Mitchell, L E. Moser, K J. Moore, D D. Redfearn Apr 2024

Morphological Development Rates Of Perennial Forage Grasses, R B. Mitchell, L E. Moser, K J. Moore, D D. Redfearn

IGC Proceedings (1997-2023)

The objective of this study was to determine the rate of change in the morphological development of switchgrass (Panicum virgatum L.) and big bluestem (Andropogon gerardii Vitman). Pure stands of each species were sampled at weekly intervals in 1990 and 1991 at Mead, NE, and morphologically classified as mean stage count (MSC) and mean stage weight (MSW). Linear day of the year equations accounted for 94% of the variation in switchgrass MSC and MSW. Switchgrass MSC and MSW increased at an average rate of 0.0204 and 0.0234 units per day, respectively. Linear day of the year equations accounted …


Physiological And Chemical Characteristics Of Five Cultivars Of Cynodon, C C.C. Gomide, L.R. De A. Rodrigues, T.De J.D. Rodrigues, R A. Reis, D A. Banzatto Feb 2024

Physiological And Chemical Characteristics Of Five Cultivars Of Cynodon, C C.C. Gomide, L.R. De A. Rodrigues, T.De J.D. Rodrigues, R A. Reis, D A. Banzatto

IGC Proceedings (1997-2023)

The experiment was carried out at UNESP, Brazil, to evaluate five Cynodon cultivars: (Cynodon nlemfuensis Vanderyst cv “Tifton 68”, Cynodon spp. cv “Tifton 85”, Cynodon dactylon cv “Florakirk”, Cynodon nlemfuensis Vanderyst var. nlemfuensis cv “Florico” e Cynodon nlemfuensis Vanderyst var. nlemfuensis cv “Florona”). Plants were sampled once a week from 14 to 84 days of growth to study physiological characteristics and at 14-day intervals to study chemical characteristics. The following variables were studied: DM production, leaf/stem ratio, leaf weight/total dry matter ratio, relative growth rate, chlorophyll contents, leaf area, specific leaf area, LAI, and the contents of CP, NDF, …


The Effect Of Nitrogen Fertilisation On The Morphological Development And Growth Rate Of Star Grass (Cynodon Nlemfuensis), P. P. Del Pozo, R. S. Herrera, A. Hameleers Jun 2023

The Effect Of Nitrogen Fertilisation On The Morphological Development And Growth Rate Of Star Grass (Cynodon Nlemfuensis), P. P. Del Pozo, R. S. Herrera, A. Hameleers

IGC Proceedings (1997-2023)

Nitrogen is one of the main inputs used in forage production systems to increase productivity. However, in Cuba, the availability of fertiliser N is limited and therefore if applied, needs to be used with high efficiency. Previous studies (Johnson, 2001, Del Pozo, 2003) investigated the effects of N on growth, carbohydrate and protein content but did not consider morphological changes in Cynodon nlemfuensis. A study was therefore undertaken investigating how N application influences morphological development of the plant and how these changes might affect the efficiency of use of applied N.


Forecast Of Herbage Production Under Continuous Grazing, K. Søegaard, J. Berntsen, K. A. Nielsen, I. Thysen Feb 2023

Forecast Of Herbage Production Under Continuous Grazing, K. Søegaard, J. Berntsen, K. A. Nielsen, I. Thysen

IGC Proceedings (1997-2023)

The utilization of pasture is very sensitive to oscillations in herbage growth. The farmer’s daily planning involves decisions on pasture use as well as on the amount and composition of supplement feeding. In this planning, expected daily growth rate is an important factor. Often the knowledge and experience about the growth rate is first available after changes in management should have been made. A different growth rate than expected should lead to changes in the grazing area or in the supplement feeding. Therefore, a simple model of grass/clover growth under grazing and irrigated conditions was developed. From spring 2004, the …


Phytoplankton Thermal Trait Parameterization Alters Community Structure And Biogeochemical Processes In A Modeled Ocean, Stephanie I. Anderson, Clara Fronda, Andrew D. Barton, Sophie Clayton, Tatiana A. Rynearson, Stephanie Dutkiewicz Jan 2023

Phytoplankton Thermal Trait Parameterization Alters Community Structure And Biogeochemical Processes In A Modeled Ocean, Stephanie I. Anderson, Clara Fronda, Andrew D. Barton, Sophie Clayton, Tatiana A. Rynearson, Stephanie Dutkiewicz

OES Faculty Publications

Phytoplankton exhibit diverse physiological responses to temperature which influence their fitness in the environment and consequently alter their community structure. Here, we explored the sensitivity of phytoplankton community structure to thermal response parameterization in a modelled marine phytoplankton community. Using published empirical data, we evaluated the maximum thermal growth rates (μmax) and temperature coefficients (Q10; the rate at which growth scales with temperature) of six key Phytoplankton Functional Types (PFTs): coccolithophores, cyanobacteria, diatoms, diazotrophs, dinoflagellates, and green algae. Following three well-documented methods, PFTs were either assumed to have (1) the same μmax and …


Ubjective Information And Survival In A Simulated Biological System, Tyler S. Barker, Massimiliano Pierobon, Peter J. Thomas Apr 2022

Ubjective Information And Survival In A Simulated Biological System, Tyler S. Barker, Massimiliano Pierobon, Peter J. Thomas

School of Computing: Faculty Publications

Information transmission and storage have gained traction as unifying concepts to characterize biological systems and their chances of survival and evolution at multiple scales. Despite the potential for an information-based mathematical framework to offer new insights into life processes and ways to interact with and control them, the main legacy is that of Shannon’s, where a purely syntactic characterization of information scores systems on the basis of their maximum information efficiency. The latter metrics seem not entirely suitable for biological systems, where transmission and storage of different pieces of information (carrying different semantics) can result in different chances of survival. …


Far-Red Photography For Measuring Plant Growth: A Novel Approach, Cole Webb, F. Mitchell Westmoreland, Bruce Bugbee, Xiaojun Qi Jan 2022

Far-Red Photography For Measuring Plant Growth: A Novel Approach, Cole Webb, F. Mitchell Westmoreland, Bruce Bugbee, Xiaojun Qi

Techniques and Instruments

A critical part of agricultural studies is determining plant stress and growth rate. Modern computer vision provides a series of tools that can be applied to derive this data. In this paper, we will show our findings, analyze their accuracy, and define a system capable of deriving this data with near-human accuracy in a fraction of the time. Denoising techniques applicable to this system will be discussed, as will our discoveries and findings. Finally, suggestions for further research opportunities will be provided.


Genotype-Specific Lesion Growth Rates In Stargardt Disease, Rachael C. Heath Jeffery, Jennifer A. Thompson, Johnny Lo, Tina M. Lamey, Terri L. Mclaren, Ian L. Mcallister, Ian J. Constable, John N. De Roach, Fred K. Chen Dec 2021

Genotype-Specific Lesion Growth Rates In Stargardt Disease, Rachael C. Heath Jeffery, Jennifer A. Thompson, Johnny Lo, Tina M. Lamey, Terri L. Mclaren, Ian L. Mcallister, Ian J. Constable, John N. De Roach, Fred K. Chen

Research outputs 2014 to 2021

Reported growth rates (GR) of atrophic lesions in Stargardt disease (STGD1) vary widely. In the present study, we report the longitudinal natural history of patients with confirmed bial-lelic ABCA4 mutations from five genotype groups: c.6079C > T, c.[2588G > C;5603A > T], c.3113C > T, c.5882G > A and c.5603A > T. Fundus autofluorescence (AF) 30◦ × 30◦ images were manually seg-mented for boundaries of definitely decreased autofluorescence (DDAF). The primary outcome was the effective radius GR across five genotype groups. The age of DDAF formation in each eye was calculated using the x-intercept of the DDAF effective radius against age. Discordance between age at DDAF …


Evaluation Of Ten Tropical Grasses In The Northwest Region Of The State Of São Paulo-Brazil, C. V. Soares Filho, L. R. De A. Rodrigues Nov 2021

Evaluation Of Ten Tropical Grasses In The Northwest Region Of The State Of São Paulo-Brazil, C. V. Soares Filho, L. R. De A. Rodrigues

IGC Proceedings (1997-2023)

The experiment was carried out in the northwest region of the State of São Paulo-Brazil to evaluate ten grasses recently introduced in the region. The grasses studied were: Cynodon nlemfuensis cv. Tifton 68, C. dactylon cv. Tifton 78, Cynodon spp. cv. Tifton 85, C. dactylon cv. Florakirk, C. nlemfuensis cv. Florico, C. nlemfuensis cv. Florona, C. dactylon cv. Coastcross, Paspalum notatum cv. Tifton 9, Brachiaria brizantha cv. Marandu, Panicum maximum cv. Tanzânia 1. The following variables were determined: DM production, growth rate, IVDMD, CP, ADF and NDF.

The GRs varied from 81 to 102 and from 14 to 26 Kg …


Effects Of Conservative Tillage On The Productive Performance Of Hunnigreen On The Fallow Of Wheat Stubbles, Hai Wang, Kuanhu Dong Feb 2021

Effects Of Conservative Tillage On The Productive Performance Of Hunnigreen On The Fallow Of Wheat Stubbles, Hai Wang, Kuanhu Dong

IGC Proceedings (1997-2023)

No abstract provided.


Turf Performance Of 19 Tall Fescue Varieties During Summer Stress, Zhiming Yang, Zhihua Li Jan 2021

Turf Performance Of 19 Tall Fescue Varieties During Summer Stress, Zhiming Yang, Zhihua Li

IGC Proceedings (1997-2023)

No abstract provided.


The Study On Cross‐Breeding Of Zoysia Willd., Hailin Guo, Jianxiu Liu, Aigui Guo Jan 2021

The Study On Cross‐Breeding Of Zoysia Willd., Hailin Guo, Jianxiu Liu, Aigui Guo

IGC Proceedings (1997-2023)

No abstract provided.


Adenosine Triphosphate (Atp) As A Metric Of Microbial Biomass In Aquatic Systems: New Simplified Protocols, Laboratory Validation, And A Reflection On Data From The Literature, Alexander B. Bochdansky, Alison N. Stouffer, Nyjaee N. Washington Jan 2021

Adenosine Triphosphate (Atp) As A Metric Of Microbial Biomass In Aquatic Systems: New Simplified Protocols, Laboratory Validation, And A Reflection On Data From The Literature, Alexander B. Bochdansky, Alison N. Stouffer, Nyjaee N. Washington

OES Faculty Publications

The use of adenosine triphosphate (ATP) as a universal biomass indicator is built on the premise that ATP concentration tracks biomass rather than the physiological condition of cells. However, reportedly high variability in ATP in response to environmental conditions is the main reason the method has not found widespread application. To test possible sources of this variability, we used the diatom Thalassiosira weissflogii as a model and manipulated its growth rate through nutrient limitation and through exposure to three different temperatures (15°C, 20°C, and 25°C). We simplified the ATP protocol with hot‐water or chemical extraction methods, modified a commercially available …


The Effect Of Planting Date On The Dry Matter Production Of Italian And Westerwolds Ryegrass In The Southern Cape Of South Africa, Philip R. Botha, Janke Van Der Colf, Lethukuthula B. Zulu, Pieter A. Swanepoel Apr 2020

The Effect Of Planting Date On The Dry Matter Production Of Italian And Westerwolds Ryegrass In The Southern Cape Of South Africa, Philip R. Botha, Janke Van Der Colf, Lethukuthula B. Zulu, Pieter A. Swanepoel

IGC Proceedings (1997-2023)

Perennial pasture species such as lucerne (Medicago sativa), kikuyu (Pennisetum clandestinum), perennial ryegrass (Lolium perenne) and perennial clovers (Trifolium spp.) make an important contribution to the fodder flow programmes for dairy production in the southern Cape. One of the main challenges when these species make up the primary pasture base within a pasture system is the mutually low growth rates during winter (Van Heerden et al., 1989; Swanepoel et al., 2014). In order to bridge pasture shortages during the critical winter months, producers establish annual Italian (Lolium multiflorum var. italicum …


Effect Of Nitrogen Fertiliser Applications On Botanical Composition, Lydia R. Turner, Daniel J. Donaghy, Keith G. Pembleton, Richard P. Rawnsley Mar 2020

Effect Of Nitrogen Fertiliser Applications On Botanical Composition, Lydia R. Turner, Daniel J. Donaghy, Keith G. Pembleton, Richard P. Rawnsley

IGC Proceedings (1997-2023)

The diminishing returns associated with nitrogen (N) fertiliser use over time are well recognised, as are the detrimental effect to the environment of excess N fertiliser use (Eckard 1998). However, many Tasmanian dairy farmers apply continually high rates of N fertiliser (e.g. in excess of 500 kg/ha annually) to minimise risk associated with variable pasture dry matter (DM) yields, and this often occurs at the expense of white clover populations within the pasture (Frame 1990; Frame et al. 1998). The responses of botanical composition and perennial ryegrass DM yields to N fertiliser application rate were investigated in the …


Growth Of Bali Bulls On Rations Containing Sesbania Grandiflora In Central Lombok, Indonesia, H. Dahlanuddin, Baiq Tutik Yuliana, Tanda Panjaitan, Michael J. Halliday, H. Max Shelton Dec 2019

Growth Of Bali Bulls On Rations Containing Sesbania Grandiflora In Central Lombok, Indonesia, H. Dahlanuddin, Baiq Tutik Yuliana, Tanda Panjaitan, Michael J. Halliday, H. Max Shelton

IGC Proceedings (1997-2023)

The demand for meat in Indonesia is currently growing by up to 8% per year, with beef cattle fattening identified as a major livestock industry (Purwantara et al. 2012). Bali cattle (Bos javanicus) account for almost 27% of total beef cattle in Indonesia; they are the predominant breed in the eastern islands and are highly favoured by smallholder farmers for their high fertility, low calf mortality and generally higher price at markets (Purwantara et al. 2012). Lombok in west Nusa Tenggara is one of the biggest suppliers of Bali cattle in Indonesia.

A major constraint to …


"The Effects Of Ocean Warming And Sedimentation On The Survival And Growth Of Acropora Cervicornis" And "Differential Prevalence Of Chimerism During Embryogenesis In Corals", Hayley De Marchis Nov 2017

"The Effects Of Ocean Warming And Sedimentation On The Survival And Growth Of Acropora Cervicornis" And "Differential Prevalence Of Chimerism During Embryogenesis In Corals", Hayley De Marchis

HCNSO Student Theses and Dissertations

Part I:

Coral reefs are essential to coastal economies, protecting coastlines from storms, and harboring high biodiversity. However, reefs are declining due to local anthropogenic stressors and ocean warming. Sedimentation, a local stressor, aggravates the impacts of warming on corals and hinders their survival and growth. Therefore, it is important to investigate whether sedimentation and temperature have a synergistic effect on vulnerable coral species, especially during earlier stages of development. To quantify these effects, survival and growth of newly settled Acropora cervicornis corals were measured at two temperatures (29 and 31°C, representing current and predicted for 2050 Summer temperatures) and …


Age And Growth Of Whale Sharks (Rhincodon Typus) Near The South Ari Atoll, Maldives, Cameron T. Perry Mar 2017

Age And Growth Of Whale Sharks (Rhincodon Typus) Near The South Ari Atoll, Maldives, Cameron T. Perry

HCNSO Student Theses and Dissertations

The whale shark (Rhincodon typus) has a global distribution in warm to warm temperate oceans, and is a species of high conservation concern currently categorized as Endangered on the International Union for Conservation of Nature (IUCN) Red List. Despite its dire conservation status and concerns about the growing number of ecotourism interactions with this species worldwide, relatively little information is available on key aspects of whale shark biology such as growth rates, reproductive rates, survival rates and breeding habitats. In particular, critical information such as age and growth of whale sharks is needed to improve the management and …


Effects Of Temperature, Irradiance And Pco2 On The Growth And Nitrogen Utilization Of Prorocentrum Donghaiense, Zhangxi Hu, Margaret R. Mulholland, Ning Xu, Shunshan Duan Jan 2016

Effects Of Temperature, Irradiance And Pco2 On The Growth And Nitrogen Utilization Of Prorocentrum Donghaiense, Zhangxi Hu, Margaret R. Mulholland, Ning Xu, Shunshan Duan

OES Faculty Publications

Environmental factors such as temp erature, irradiance, and nitrogen (N) supply affect the growth of Prorocentrum donghaiense, but the interactive effects of these physical factors and the effects of atmospheric CO2 (pCO2) on growth and N uptake have not been examined. We compared growth kinetics of P. donghaiense grown on 4 different N substrates (nitrate [NO3 -], ammonium [NH4 +], urea, and glutamic acid [glu]) with respect to temperature, irradiance, and pCO2. Temperature (15 to 30°C) had a positive effect on growth (max. growth rates: 0.17 to 0.65 d …


Survival And Growth Rate Of Translocated Freshwater Mussels Lampsilis Fasciola And Medionidus Conradicus, Laura L. Pullum Aug 2015

Survival And Growth Rate Of Translocated Freshwater Mussels Lampsilis Fasciola And Medionidus Conradicus, Laura L. Pullum

Masters Theses

Freshwater mussels (Family Unionidae and Margaritiferidae) are a widely threatened group of bivalve molluscs, particularly in the Southeastern United States. Translocation of freshwater mussels is an increasingly common conservation method. However, there are relatively few studies that quantitatively investigate the factors influencing translocation success or failure. In October 2013, hundreds of Medionidus conradicus and Lampsilis fasciola were translocated to the Pigeon and Nolichucky Rivers in Tennessee, with an interim partial survey (June 2014) and a full survey (October 2014). In this study, I analyze this field-collected data to determine the mechanism(s) that currently influence the outcomes of Tennessee mussel translocation. …


Survival, Growth, And Settlement Of Dreissena Rostriformis Bugensis Veligers In Low And High Calcium Waters, Emma Ruhmann Aug 2014

Survival, Growth, And Settlement Of Dreissena Rostriformis Bugensis Veligers In Low And High Calcium Waters, Emma Ruhmann

UNLV Theses, Dissertations, Professional Papers, and Capstones

Populations ofDreissena rostriformis bugensis(quagga mussels) have continued to spread throughout the western United States since their discovery in the Boulder Basin of Lake Mead, NV-AZ in early 2007. Today, quagga mussel specific research is still lacking and the physicochemical characteristics of aquatic systems required by quagga mussels to successfully establish is not fully understood. This includes an absence of research in aquatic environments in the western United States and on quagga mussel veligers (larval stage). Calcium is considered the defining factor for determining if a lake or river is suitable for quagga mussel establishment. The minimum calcium threshold for invasion …


Patterns Of Larval Atlantic Croaker Ingress Into Chesapeake Bay, Usa, Jason J. Schaffler, Christian S. Reiss, Cynthia M. Jones Jan 2009

Patterns Of Larval Atlantic Croaker Ingress Into Chesapeake Bay, Usa, Jason J. Schaffler, Christian S. Reiss, Cynthia M. Jones

OES Faculty Publications

We compared ingress patterns of Atlantic croaker Micropogonias undulatus larvae into Chesapeake Bay, USA, with published ingress patterns through barrier island inlets, the accepted model for larval fish ingress. This model asserts that larvae ingress on night flood tides at the flooddominated side of the inlet and at all depths. At the Chesapeake Bay mouth and in the adjacent coastal waters, we compared the distribution of abundance, size, age, and growth rates of croaker prior to ingress, In contrast to the barrier island inlet model, croaker larvae were more abundant at depth than closer to the surface regardless of location. …


Sheep Updates 2008 - Part 3, L. J. E. Karlsson, J. C. Greeff, L. Slocombe, K. Jones, N. Underwood, Fred Wilkinson, W. D. Hoffman, W. A. Mckiernan, V. H. Oddy, M. J. Mcphee, B. L. Mcintyre, P. F. Parnell, R. A. Clark, J. Timms, G. Griffith, C. Mulholland, P. Hyland, Danielle England, Fiona Jones, John Lucey, Martin Staines, Richard Morris, Megan Abrahams, Caroline Peek, Dennis Van Gool, Daniel Gardiner, Kari-Lee Falconer, Sandra Prosser, Mario D'Antuono, John Young, Andrew Thompson, Chris Oldham, Brown Besier, Angus Campbell, Ralph Behrendt Jul 2008

Sheep Updates 2008 - Part 3, L. J. E. Karlsson, J. C. Greeff, L. Slocombe, K. Jones, N. Underwood, Fred Wilkinson, W. D. Hoffman, W. A. Mckiernan, V. H. Oddy, M. J. Mcphee, B. L. Mcintyre, P. F. Parnell, R. A. Clark, J. Timms, G. Griffith, C. Mulholland, P. Hyland, Danielle England, Fiona Jones, John Lucey, Martin Staines, Richard Morris, Megan Abrahams, Caroline Peek, Dennis Van Gool, Daniel Gardiner, Kari-Lee Falconer, Sandra Prosser, Mario D'Antuono, John Young, Andrew Thompson, Chris Oldham, Brown Besier, Angus Campbell, Ralph Behrendt

Sheep Updates

This session covers fiveteen papers from different authors:

CONTROLLING FLY STRIKE

1. Breeding for Blowfly Resistance - Indicatoe Traits, LJE Karlsson, JC Greeff, L Slocombe, Department of Agriculture & Food, Western Australia

2.A practical method to select for breech strike resistance in non-pedigreed Merino flocks, LJE Karlsson, JC Greeff, L Slocombe, K. Jones, N. Underwood, Department of Agriculture & Food, Western Australia

3. Twice a year shearing - no mulesing, Fred Wilkinson, Producer, Brookton WA

BEEF

4. Commercial testing of a new tool for prediction of fatness in beef cattle, WD HoffmanA, WA McKiernanA, VH Oddy …


Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins Jan 2008

Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins

OES Faculty Publications

We examined the physiological responses of steady-state iron (Fe)-replete and Fe-limited cultures of the biogeochemically critical marine unicellular diazotrophic cyanobacterium Crocosphaera at glacial (19 Pa; 190 ppm), current (39 Pa; 380 ppm), and projected year 2100 (76 Pa; 750 ppm) CO2 levels. Rates of N2 and CO2 fixation and growth increased in step with increasing partial pressure of CO2 (pCO2), but only under Fe- replete conditions. N2) and carbon fixation rates at 75 Pa CO2 were 1.4-1.8-fold and 1.2-2.0-fold higher, respectively, relative to those at present day and glacial pCO2 …


Root Exploitation Of Fertile Soil Microsites, Robert B. Jackson May 1989

Root Exploitation Of Fertile Soil Microsites, Robert B. Jackson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Root exploitation of enriched soil microsites was examined for the tussock grasses Agropyron desertorum and Agropyron spicatum and the shrub Artemisia tridentata. Two mechanisms of exploitation of the microsites were examined: root proliferation and changes in nutrient uptake capacity. One day after nutrient solution was applied to small soil patches, the mean relative growth rate of Agropyron desertorum roots in enriched patches was two to four times greater than for roots of the same plants in soil patches treated with distilled water. This rapid and striking root proliferation occurred in response to N-P-K enrichment as well as to P or …