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Full-Text Articles in Plant Sciences

Melamine Contamination Of Infant Formula In China: The Causes, Food Safety Issues And Public Health Implications, Emmanuel Ohene Afoakwa Nov 2008

Melamine Contamination Of Infant Formula In China: The Causes, Food Safety Issues And Public Health Implications, Emmanuel Ohene Afoakwa

Professor Emmanuel Ohene Afoakwa

No abstract provided.


No Evidence That Bacillus Thuringiensis Genes And Their Products Influence The Susceptibility Of Corn Residue To Decomposition, R. Michael Lehman, Shannon L. Osborne, Kurt A. Rosentrater Nov 2008

No Evidence That Bacillus Thuringiensis Genes And Their Products Influence The Susceptibility Of Corn Residue To Decomposition, R. Michael Lehman, Shannon L. Osborne, Kurt A. Rosentrater

Kurt A. Rosentrater

The possibility that Bacillus thuringiensis (Bt) corn (Zea mays L.) residues resist decomposition compared to non-Bt residues would present direct (soil carbon turnover times) and indirect (changes in tillage practices) effects on carbon budgets in agricultural systems. We evaluated the relative decomposition of residue from two pairs of Bt and non-Bt corn hybrids from different seed manufacturers buried in the root zone of adjacent Bt and non-Bt corn plots over a period of 384 d. We found no persistent differences in residue decomposition among the different hybrids regardless of the seed manufacturer or the presence of the Bt genes (both …


School Feeding Programmes In Africa - A Case Study, Emmanuel Ohene Afoakwa Jul 2008

School Feeding Programmes In Africa - A Case Study, Emmanuel Ohene Afoakwa

Professor Emmanuel Ohene Afoakwa

No abstract provided.


Improving Productivity In Mixed-Species Plantations, Mila Bristow, J Doland Nichols, Jerome K. Vanclay Jun 2008

Improving Productivity In Mixed-Species Plantations, Mila Bristow, J Doland Nichols, Jerome K. Vanclay

Professor Jerome K Vanclay

Mixed species plantations are often promoted as being environmentally preferable to monocultures, but are rarely considered operationally viable by commercial forest growers. Despite many publications documenting benefits demonstrated in research studies (e.g., Kelty 2006; Forrester et al. 2006b; Wood and Vanclay 1995), and despite continuing calls from a wide range of advocates for mixed-species plantations, polyculture remains the exception rather than the rule in industrial plantation forestry (Nichols et al 2006)...


Extraction Of Lipids From Buttermilk Using Supercritical Carbon Dioxide, Harit K. Vyas, Johanna C. Astaire, Rafael Jiménez-Flores May 2008

Extraction Of Lipids From Buttermilk Using Supercritical Carbon Dioxide, Harit K. Vyas, Johanna C. Astaire, Rafael Jiménez-Flores

Rafael Jiménez-Flores

Abstract of paper presented at the 2002 Joint Annual Meeting of the American Dairy Science Association & the American Society of Animal Science.


Disulfide Bonding Patterns Between Β-Lactoglobulin And Κ-Casein In A Heated And Spray-Dried Milk-Model, Annie Bienvenue, C. S. Norris, Michael J. Boland, Lawrence K. Creamer, Rafael Jiménez-Flores May 2008

Disulfide Bonding Patterns Between Β-Lactoglobulin And Κ-Casein In A Heated And Spray-Dried Milk-Model, Annie Bienvenue, C. S. Norris, Michael J. Boland, Lawrence K. Creamer, Rafael Jiménez-Flores

Rafael Jiménez-Flores

Abstract of paper presented at the 2002 Joint Annual Meeting of the American Dairy Science Association & the American Society of Animal Science.


Iron Fertilization Of Kentucky Bluegrass, David Wehner, Jean Haley May 2008

Iron Fertilization Of Kentucky Bluegrass, David Wehner, Jean Haley

David J. Wehner

Iron applications are sometimes used to enhance the color (darker green) of turfgrass stands even when iron is not deficient. A study was conducted to determine the feasibility of replacing a portion of the total yearly N applied to Kentucky bluegrass (Poa pratensis L.) with iron. Turfgrass response to iron chelate (Sequestrene 330) applications at 2.2 kg Fe ha-1 in combination with three liquid-applied N sources (urea, Formolene, and FLUF) at 25 kg N ha-1 was compared to turf response from applications of the N sources at 49 kg N ha-1. Iron was substituted for …


Building Sustainable Agricultural Development Through Home-Grown School Feeding - The African Approach, Emmanuel Ohene Afoakwa, Linley Chiwona-Karltun Apr 2008

Building Sustainable Agricultural Development Through Home-Grown School Feeding - The African Approach, Emmanuel Ohene Afoakwa, Linley Chiwona-Karltun

Professor Emmanuel Ohene Afoakwa

Proper nutrition is critical for optimal growth, cognitive development, general well-being and academic performance of children. Access to good nutrition either at home or through the educational system can contribute to the elimination of malnutrition and its associated health and developmental problems. In this regard, The 2005 UN World Summit recommended the expansion of local school feeding programmes, using home-grown foods where possible as one of the “Quick impact initiatives” to achieve the Millennium Development Goals, especially for rural areas facing the dual challenge of high chronic malnutrition and low agricultural productivity.


A Microecosystem For Fertilizer And Pesticide Fate Research, B. E. Branham, David J. Wehner, W. A. Torello, A. J. Turgeon Apr 2008

A Microecosystem For Fertilizer And Pesticide Fate Research, B. E. Branham, David J. Wehner, W. A. Torello, A. J. Turgeon

David J. Wehner

A microecosystem was designed to study the behavior of pesticides, fertilizers, or related compounds applied to plant stands. The system consists of three parts: a brass base that holds the plant growth media, a glass atmospheric chamber that rests on the base, and a set of analytical traps. The brass base is fitted with a porous ceramic plate so that tension can be applied to the water in the growing media. Air enters the bottom of the glass atmospheric chamber and exits through the top into appropriate trapping systems to recover volatilized pesticides, ammonia, or metabolized 14CO2 from labeled compounds. …


The Fate Of Diazinon Applied To Thatched Turf, B. E. Branham, David J. Wehner Apr 2008

The Fate Of Diazinon Applied To Thatched Turf, B. E. Branham, David J. Wehner

David J. Wehner

Diazinon (0,0-diethyl-0-(2-isopropyl-6-methyl-4-primidinyl) phosphorothioate) is widely used to control turfgrass insect pests. Poor control of soil-inhabiting insects has been found where diazinon has been applied to thatched turfgrass stands. The purpose of this study was to evaluate the environmental fate of diazinon applied to turfgrass stands. A microecosystem was used to follow the fate of radiolabeled diazinon surface applied to Kentucky bluegrass (Poa pratensis L.) turfs, with or without a thatch layer, growing on Flanigan silt loam (fine, montmorillonitic, mesic Aquic Argiudoll) irrigated daily or every 4 days. Loss of diazinon by volatilization, leaching, and degradation accompanied by release of …


Heat Tolerance Screening Of Field-Grown Cultivars Of Kentucky Bluegrass And Perennial Ryegrass, D. D. Minner, P. H. Dernoeden, David J. Wehner, M. S. Mcintosh Apr 2008

Heat Tolerance Screening Of Field-Grown Cultivars Of Kentucky Bluegrass And Perennial Ryegrass, D. D. Minner, P. H. Dernoeden, David J. Wehner, M. S. Mcintosh

David J. Wehner

The quality of cool-season turfgrasses frequently declines during periods of high temperature stress. Simple tests are needed to rapidly identify heat tolerant germplasm for incorporation into breeding programs. Facilitative screening tests have been devised, however, in the few studies that have been performed only immature and greenhouse or growth chamber-grown plants have been evaluated. To be of practical value, results of screening tests, employing plants grown under artificial conditions, should correlate closely with results of tests involving field grown plants. The objective of this research was to evaluate the heat tolerance of several cultivars of Kentucky bluegrass (Poa pratensis L.) …


Urease Activity In A Kentucky Bluegrass Turf, W. A. Torello, David J. Wehner Apr 2008

Urease Activity In A Kentucky Bluegrass Turf, W. A. Torello, David J. Wehner

David J. Wehner

The components of a turfgrass ecosystem, including plants, an intervening layer of thatch and the underlying soil, influence the fate of topically applied urea fertilizer. The loss of urea N by ammonia volatilization may be governed by the rate of urea hydrolysis. The main objective of this study was to determine the extent of urease activity associated with turfgrass plant tissue, thatch, and the underlying soil. This information may help elucidate the mechanism of ammonia loss following urea application. Because a turfgrass stand frequently possesses an extensive thatch layer that may serve as the primary plant growth medium, additional objectives …


Heat Tolerance Of Kentucky Bluegrasses, Perennial Ryegrasses, And Annual Bluegrass, David J. Wehner, T. L. Watschke Apr 2008

Heat Tolerance Of Kentucky Bluegrasses, Perennial Ryegrasses, And Annual Bluegrass, David J. Wehner, T. L. Watschke

David J. Wehner

Use of cool-season turfgrasses in transitional environments is limited, in part, by their heat tolerance. Development of a rapid heat tolerance screening technique would be of value in determining the potential of turf•grasses for use in warmer areas. The heat tolerance of 22 Kentucky bluegrass (Poa pratensis L.) cultivars, Poa annua L., and four perennial ryegrass cultivars (Lolium perenne L.) was evaluated by exposing plants for 30 min to temperatures ranging from 41 to 49 C in single degree intervals. Ten-week-old plants, which had been grown under a low level of N fertilization and watered infrequently to maximize heat tolerance …


Heat Tolerance Of Kentucky Bluegrasses, Perennial Ryegrasses, And Annual Bluegrass, David J. Wehner, T. L. Watschke Apr 2008

Heat Tolerance Of Kentucky Bluegrasses, Perennial Ryegrasses, And Annual Bluegrass, David J. Wehner, T. L. Watschke

David J. Wehner

Use of cool-season turfgrasses in transitional environments is limited, in part, by their heat tolerance. Development of a rapid heat tolerance screening technique would be of value in determining the potential of turf•grasses for use in warmer areas. The heat tolerance of 22 Kentucky bluegrass (Poa pratensis L.) cultivars, Poa annua L., and four perennial ryegrass cultivars (Lolium perenne L.) was evaluated by exposing plants for 30 min to temperatures ranging from 41 to 49 C in single degree intervals. Ten-week-old plants, which had been grown under a low level of N fertilization and watered infrequently to maximize heat tolerance …


Effect Of P, K, And Lime On Growth, Composition, And P Absorption By Merion Kentucky Bluegrass, T. L. Watschke, D. V. Waddington, David J. Wehner, C. L. Forth Apr 2008

Effect Of P, K, And Lime On Growth, Composition, And P Absorption By Merion Kentucky Bluegrass, T. L. Watschke, D. V. Waddington, David J. Wehner, C. L. Forth

David J. Wehner

Information is needed concerning the effects of different soil fertility levels on the activity of turfgrass roots in that part of the soil profile sampled for routine soil tests. In Pennsylvania, a sampling depth of 5 to 7.5 cm is suggested for established turf. A study was conducted on 'Merion' Kentucky bluegrass (Poa pratensis L.) to determine relationships among lime, phosphorus, and potassium applications; soil test results; foliar growth and elemental analysis; and root activity as determined by 32P uptake from three soil depths. In the field, soil pH values were 5.8 and 7.0, P ranged from 13 to 137 …


Models For Predicting The Lower Limit Of The Canopy-Air Temperature Difference Of Two Cool Season Grasses, Dennis Martin, David Wehner, C. Throssell Apr 2008

Models For Predicting The Lower Limit Of The Canopy-Air Temperature Difference Of Two Cool Season Grasses, Dennis Martin, David Wehner, C. Throssell

David J. Wehner

Estimation of the lower limit of the canopy-air temperature differential, (Tc–Ta)LL, is required for calculation of an empirically-based crop water stress, index. This research determined the complexity of model needed for accurate estimation of (Tc–Ta)LL for several field grown cultivars of Kentucky bluegrass (Poa pratensis L.) and for creeping bentgrass (Agrostis stolonifera L. var. palustris (Huds.) Farw.). Regression models using vapor pressure deficit of the air (VPD), net radiation load (Rn), and wind speed (WS) were developed for predicting (Tc–Ta …


Melamine/Urea And Oxamide Fertilization Of Kentucky Bluegrass, David Wehner, Dennis Martin Apr 2008

Melamine/Urea And Oxamide Fertilization Of Kentucky Bluegrass, David Wehner, Dennis Martin

David J. Wehner

The commercial lawn care industry represents a large market for N sources. A formulated melamine (2,4,6-triamino-s-triazine) plus urea combination (MLU) (45% melamine by weight) and oxamide were evaluated for use by the lawn care industry by comparing turfgrass response from these fertilizers to that from urea, sulfur coated urea (SCU), ureaformaldehyde (Nitroform), and a non-fertilized check. Fertilizers were applied four times per year to field plots of Kentucky bluegrass (Poa pratensis L.) growing on a Flanagan silt loam (fine, montmorillonitic, mesic Aquic Argiudoll) at a rate of 49 kg N ha-1 per application. Color ratings and clipping weights were determined …


Climate Change And Freshwater Resources, Noah D. Hall, Bret B. Stuntz, Robert H. Abrams Jan 2008

Climate Change And Freshwater Resources, Noah D. Hall, Bret B. Stuntz, Robert H. Abrams

Noah D Hall

The Earth’s climate is warming. This is the unequivocal conclusion of climate scientists. Despite the complexities of climatology, certain consistent trends emerge with implications for water availability: as the world gets warmer, it will experience increased regional variability in precipitation, with more frequent heavy precipitation events and more susceptibility to drought. These simple facts will have a profound impact on freshwater resources throughout the United States, as the warmer climate will reduce available water supplies and increase water demand. Unfortunately, current water law and policy are not up to the new challenges of climate change and resulting pressures on freshwater …


Risks, Farmers’ Suicides And Agrarian Crisis In India: Is There A Way Out?, Srijit Mishra Jan 2008

Risks, Farmers’ Suicides And Agrarian Crisis In India: Is There A Way Out?, Srijit Mishra

Srijit Mishra

Poor returns to cultivation and absence of non-farm opportunities are indicative of the larger socio-economic malaise in rural India. This is accentuated by the multiple risks that the farmer faces – yield, price, input, technology and credit among others. The increasing incidence of farmers’ suicides is symptomatic of a larger crisis, which is much more widespread. Risk mitigation strategies should go beyond credit. Long term strategies requires more stable income from agriculture, and more importantly, from non-farm sources. Private credit and input markets need to be regulated. A challenge for the technological and financial gurus is to provide innovative products …


Long-Term Tillage Frequency Effects On Dryland Soil Physical And Hydraulic Properties, Andrew W. Lenssen, J. D. Jabro, U. M. Sainju, W. B. Stevens, R. G. Evans Jan 2008

Long-Term Tillage Frequency Effects On Dryland Soil Physical And Hydraulic Properties, Andrew W. Lenssen, J. D. Jabro, U. M. Sainju, W. B. Stevens, R. G. Evans

Andrew W. Lenssen

Soil tillage is considered one of most important practices in agricultural production due to its influence on physical, chemical, and biological properties of the soil environment. The effect of a long-term tillage [no-till (NT), spring till (ST), and fall and spring till (FST)] was investigated on soil penetration resistance (PR), bulk density (BD), gravimetric water content (GWC) and saturated hydraulic conductivity (Ks) under dryland conditions. Tillage effects on these physical properties were tested after 22 years on a Dooley sandy loam (fine-loamy, mixed Typic Argiborolls) derived from glacial till parent material. The statistical design used was a randomized complete block …


Evaluation Of Winter Cereals For Pasture In Montana, Andrew W. Lenssen, A. N. Hafla, S. D. Cash, L. M. M. Surber, J. A. Paterson, A. L. Todd, M. S. Huffman Jan 2008

Evaluation Of Winter Cereals For Pasture In Montana, Andrew W. Lenssen, A. N. Hafla, S. D. Cash, L. M. M. Surber, J. A. Paterson, A. L. Todd, M. S. Huffman

Andrew W. Lenssen

In the southern Great Plains, it is common to graze winter wheat pastures prior to grain harvest to take advantage of economic returns from the grain crop and value added to livestock. In Montana, a similar management practice could provide complementary pasture for livestock in the late spring to relieve pressure on cool season native rangelands. A two year study was conducted to evaluate the forage yield and quality of winter cereals, when grazed at three growth stages, vegetative (V), boot stage (B), and at heading (H), prior to hay and grain harvest. Western white faced ewes were used to …


No Differences In Decomposition Rates Observed Between Bacillus Thuringiensis And Non-Bacillus Thuringiensis Corn Residue Incubated In The Field, R. Michael Lehman, Shannon L. Osborne, Kurt A. Rosentrater Jan 2008

No Differences In Decomposition Rates Observed Between Bacillus Thuringiensis And Non-Bacillus Thuringiensis Corn Residue Incubated In The Field, R. Michael Lehman, Shannon L. Osborne, Kurt A. Rosentrater

Kurt A. Rosentrater

Recent speculation of slower residue decomposition for Bacillus thuringiensis (Bt) corn (Zea mays L.) hybrids compared with non-Bt corn hybrids has prompted investigative study. We evaluated the residue decomposition rates of Bt and non-Bt corn hybrids over a period of 22 mo under field conditions using the litter bag technique. The four corn hybrids used were (i) DKC60–16 (Bt+, Cry1Ab protein active against the leptidopteran European corn borer, event MON810), (ii) DKC60–12 (Bt+, Cry3Bb1 protein active against the coleopteran corn rootworm, event MON863), (iii) DKC60–14 (stacked Bt++, Cry1Ab and Cry3Bb1 proteins) and, (iv) DKC60–15 (Bt−, base genetics). The biochemical and …