Spelling suggestions: "subject:"roundup ready"" "subject:"roundup heady""
11 |
Microbial community structure and nematode diversity in soybean-based cropping systems / Chantelle JansenJansen, Chantelle January 2014 (has links)
Soil is an important ecosystem that supports a wide variety of organisms such as bacteria,
fungi, arthropods and nematodes. This sensitive ecosystem may be influenced by various
factors, including agricultural management practices. With the introduction of genetically
modified (GM) glyphosate-tolerant (RoundUp ® Ready: RR) crops, herbicides such as
glyphosate have been increasingly used. However, little is known about the effect of
glyphosate on the biological communities in these herbicide-sprayed soils. With the intimate
proximity that microorganisms and nematodes have with the roots of plants, these
organisms can be used to assess changes that may occur in the soil surrounding roots of
RR crops. The aim of this study was to determine microbial community structure and
nematode diversity, with emphasis on that of non-parasitic nematodes, in soil samples from
conventional soybean (CS) - and RR- soybean fields compared to that in adjacent natural
veld (NV) areas.
Samples were collected from twenty three sites at six localities that are situated within the
soybean-production areas of South Africa. These sites represented fields where RR and CS
soybean grew, as well as surrounding NV. All RR fields have been treated with glyphosate
for no less than five years. Microbial community structures of the twenty three sites in the
RR, CS and NV ecosystems were determined by phospholipid fatty acid (PLFA) analyses.
Nematode diversity was determined by extracting the nematodes from soil samples and
conducting a faunal analysis. Soil physical and chemical properties were determined by an
independent laboratory, Eco-Analytica (North West University, Potchefstroom) according to
standard procedures.
Results from this study indicated differences in microbial community structure between the
various localities. However, there were no significant (p ≤ 0.05) differences in microbial
community structures between RR- and CS ecosystems. Soils of both RR- and CS crops
were primarily dominated by bacteria. Nematode identification and faunal analysis also
indicated no significant (p ≤ 0.05) differences between the different non-parasitic/beneficial
nematodes that were present in soils of these two ecosystems during the time of sampling.
Non-parasitic nematode communities were primarily dominated by bacterivores. A faunal
analysis indicated that most of the sites contained enriched, but unstructured soil food-webs.
However, four of the sites showed enriched and structured food webs due to the presence of
non-parasitic nematodes with high coloniser-persister (cp) values. Relationships between non-parasitic nematode – and microbial communities showed that there was a positive
relationship between nematode functional groups and their corresponding microbial prey.
From the results obtained in this study, it can be concluded that the community structures of
both non-parasitic nematodes and microorganisms shared similarities. These community
structures showed no long-term detrimental effects of glyphosate application in the soils
surrounding roots of RR soybean crops. Relationships existed between non-parasitic
nematode and microbial communities in the rhizosphere of soybean crops and natural veld.
For example, bacterivore nematodes had a strong positive relationship with gram-negative
bacteria. Similar but weaker relationships also existed between carnivores, omnivores, plantparasitic
nematodes and gram-negative bacteria. A positive relationship also existed
between fungivores and fungal fatty acids. This emphasises the value of these organisms as
indicators of soil health and also the impact that agricultural practices can have on soils. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014
|
12 |
Microbial community structure and nematode diversity in soybean-based cropping systems / Chantelle JansenJansen, Chantelle January 2014 (has links)
Soil is an important ecosystem that supports a wide variety of organisms such as bacteria,
fungi, arthropods and nematodes. This sensitive ecosystem may be influenced by various
factors, including agricultural management practices. With the introduction of genetically
modified (GM) glyphosate-tolerant (RoundUp ® Ready: RR) crops, herbicides such as
glyphosate have been increasingly used. However, little is known about the effect of
glyphosate on the biological communities in these herbicide-sprayed soils. With the intimate
proximity that microorganisms and nematodes have with the roots of plants, these
organisms can be used to assess changes that may occur in the soil surrounding roots of
RR crops. The aim of this study was to determine microbial community structure and
nematode diversity, with emphasis on that of non-parasitic nematodes, in soil samples from
conventional soybean (CS) - and RR- soybean fields compared to that in adjacent natural
veld (NV) areas.
Samples were collected from twenty three sites at six localities that are situated within the
soybean-production areas of South Africa. These sites represented fields where RR and CS
soybean grew, as well as surrounding NV. All RR fields have been treated with glyphosate
for no less than five years. Microbial community structures of the twenty three sites in the
RR, CS and NV ecosystems were determined by phospholipid fatty acid (PLFA) analyses.
Nematode diversity was determined by extracting the nematodes from soil samples and
conducting a faunal analysis. Soil physical and chemical properties were determined by an
independent laboratory, Eco-Analytica (North West University, Potchefstroom) according to
standard procedures.
Results from this study indicated differences in microbial community structure between the
various localities. However, there were no significant (p ≤ 0.05) differences in microbial
community structures between RR- and CS ecosystems. Soils of both RR- and CS crops
were primarily dominated by bacteria. Nematode identification and faunal analysis also
indicated no significant (p ≤ 0.05) differences between the different non-parasitic/beneficial
nematodes that were present in soils of these two ecosystems during the time of sampling.
Non-parasitic nematode communities were primarily dominated by bacterivores. A faunal
analysis indicated that most of the sites contained enriched, but unstructured soil food-webs.
However, four of the sites showed enriched and structured food webs due to the presence of
non-parasitic nematodes with high coloniser-persister (cp) values. Relationships between non-parasitic nematode – and microbial communities showed that there was a positive
relationship between nematode functional groups and their corresponding microbial prey.
From the results obtained in this study, it can be concluded that the community structures of
both non-parasitic nematodes and microorganisms shared similarities. These community
structures showed no long-term detrimental effects of glyphosate application in the soils
surrounding roots of RR soybean crops. Relationships existed between non-parasitic
nematode and microbial communities in the rhizosphere of soybean crops and natural veld.
For example, bacterivore nematodes had a strong positive relationship with gram-negative
bacteria. Similar but weaker relationships also existed between carnivores, omnivores, plantparasitic
nematodes and gram-negative bacteria. A positive relationship also existed
between fungivores and fungal fatty acids. This emphasises the value of these organisms as
indicators of soil health and also the impact that agricultural practices can have on soils. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014
|
13 |
Evaluation of organophosphate insecticides on performance of transgenic and conventional cottonHundley, Christopher Alan 29 August 2005 (has links)
Genetically modified cotton (Gossypium hirsutum L.) acreage has increased dramatically over the last six years. Reports of variable results in fiber quality and yield have arisen in these cultivars. Some changes in production practices have occurred coincident with the introduction of transgenic technology, such as reduced use of broad-spectrum insecticides, including organophosphates (OP) that could potentially influence the growth and yield of cotton. One factor that might affect these parameters is the difference in the amount of foliarly-applied phosphorus (P) between an OP and non-phosphate (NP) insecticide regime. Therefore, a study was conducted to investigate selected growth characteristics, yield, and fiber quality of genetically modified and conventional cotton as influenced by OP and foliar phosphorus (FP) applications. A four replication strip-plot experimental design was utilized with cultivar serving as the whole plot and insecticide regime as the sub-plot. Three cultivars of the same recurrent parent (ST4892BR, ST4793R, and ST474) were planted in 2001 and 2002 under irrigated conditions in Burleson County, TX on a Weswood silty clay loam (fine-silty, mixed, thermic Fluventic Ustochrept). The insecticide regime consisted of NP, NP+FP, and OP treatments. The FP was applied at P2O5 weight equivalent to the P component in the concurrent OP application. ST4892BR had greater lint yield than ST4793R and ST474. The yield increase can be explained through plant mapping analysis which showed ST4892BR producing larger bolls and greater boll numbers. In addition, evaluation of fruiting distribution showed ST4892BR contained more lint on sympodial branches 6 through 10. The insecticide regime effect on lint yield resulted in higher yield (P=0.08) for the NP+FP regime. Examination of yield components revealed NP+FP increased second position bolls, predominantly at sympodial branches 6 through 10. Leaf tissue analysis revealed increased levels of P for the OP and NP+FP over that of the NP insecticide regime, which indicates a potential for plants to acquire P from OP insecticides. Furthermore, the considerable yield response to small amounts of FP is not clearly understood. While conclusive evidence exists regarding cultivar yield differences, this study does not provide sufficient evidence to conclude that OP insecticides influence growth, yield, or fiber quality characteristics of these cotton cultivars.
|
14 |
Evaluation of organophosphate insecticides on performance of transgenic and conventional cottonHundley, Christopher Alan 29 August 2005 (has links)
Genetically modified cotton (Gossypium hirsutum L.) acreage has increased dramatically over the last six years. Reports of variable results in fiber quality and yield have arisen in these cultivars. Some changes in production practices have occurred coincident with the introduction of transgenic technology, such as reduced use of broad-spectrum insecticides, including organophosphates (OP) that could potentially influence the growth and yield of cotton. One factor that might affect these parameters is the difference in the amount of foliarly-applied phosphorus (P) between an OP and non-phosphate (NP) insecticide regime. Therefore, a study was conducted to investigate selected growth characteristics, yield, and fiber quality of genetically modified and conventional cotton as influenced by OP and foliar phosphorus (FP) applications. A four replication strip-plot experimental design was utilized with cultivar serving as the whole plot and insecticide regime as the sub-plot. Three cultivars of the same recurrent parent (ST4892BR, ST4793R, and ST474) were planted in 2001 and 2002 under irrigated conditions in Burleson County, TX on a Weswood silty clay loam (fine-silty, mixed, thermic Fluventic Ustochrept). The insecticide regime consisted of NP, NP+FP, and OP treatments. The FP was applied at P2O5 weight equivalent to the P component in the concurrent OP application. ST4892BR had greater lint yield than ST4793R and ST474. The yield increase can be explained through plant mapping analysis which showed ST4892BR producing larger bolls and greater boll numbers. In addition, evaluation of fruiting distribution showed ST4892BR contained more lint on sympodial branches 6 through 10. The insecticide regime effect on lint yield resulted in higher yield (P=0.08) for the NP+FP regime. Examination of yield components revealed NP+FP increased second position bolls, predominantly at sympodial branches 6 through 10. Leaf tissue analysis revealed increased levels of P for the OP and NP+FP over that of the NP insecticide regime, which indicates a potential for plants to acquire P from OP insecticides. Furthermore, the considerable yield response to small amounts of FP is not clearly understood. While conclusive evidence exists regarding cultivar yield differences, this study does not provide sufficient evidence to conclude that OP insecticides influence growth, yield, or fiber quality characteristics of these cotton cultivars.
|
15 |
Value-laden risk assessment and biotechnology regulation in CanadaAhmad, Rana Amber 17 September 2003
<p>Canadas regulatory system is science-based and relies on risk assessment to inform decisions about which products of biotechnology (and other technologies) are safe enough for commercial application. Since regulation involves the loss of certain liberties, it is imperative that any regulatory regime be as objective as possible. Scientific risk assessment seems to be a good way to produce the information, which guides policy makers since it involves quantitative analysis and the production of seemingly objective data.</p><p>The view adopted by regulators and in current risk assessment practices is that objective means value-free. Therefore, because risk assessment data is scientific it is thought to be value-free but this is not the case. Risk assessment necessarily involves value assumptions. Assumptions must be made at all stages of the production of risk data. This does not mean, however, that risk assessment is hopelessly subjective. The notion of value-free objectivity can be replaced with the view that genuine objectivity arises through peer review and social discourse. Regulators can adopt this understanding of objectivity to acknowledge the value-ladenness of risk assessment data.</p><p>At present, the value assumptions made by industry, government and private scientists during risk assessment go largely unnoticed yet have an effect on the outcome of regulatory decisions. Such assumptions must be recognized in order to ensure that the decisions made about the risks society face are not biased. This is particularly true in the case of biotechnology regulation. The development of the science of biotechnology has occurred concurrently with the development of the biotech industry creating the opportunity for industry-biased risk assessments.</p><p>It is possible to make changes to the existing regulatory regime in Canada in order to avoid some of the major problems associated with unrecognized value assumptions in risk assessment. A complete restructuring of the regime is unnecessary, however. Maintaining the current regulatory structure with some minor changes could address these problems. These changes include: creating an independent review board, making explicit that value assumptions are part of risk assessment in government advisory reports, and enhancing the role of regulators. Canadas regulatory system can better address the risks associated with biotechnology if it acknowledges that risk assessment is value-laden.</p>
|
16 |
Value-laden risk assessment and biotechnology regulation in CanadaAhmad, Rana Amber 17 September 2003 (has links)
<p>Canadas regulatory system is science-based and relies on risk assessment to inform decisions about which products of biotechnology (and other technologies) are safe enough for commercial application. Since regulation involves the loss of certain liberties, it is imperative that any regulatory regime be as objective as possible. Scientific risk assessment seems to be a good way to produce the information, which guides policy makers since it involves quantitative analysis and the production of seemingly objective data.</p><p>The view adopted by regulators and in current risk assessment practices is that objective means value-free. Therefore, because risk assessment data is scientific it is thought to be value-free but this is not the case. Risk assessment necessarily involves value assumptions. Assumptions must be made at all stages of the production of risk data. This does not mean, however, that risk assessment is hopelessly subjective. The notion of value-free objectivity can be replaced with the view that genuine objectivity arises through peer review and social discourse. Regulators can adopt this understanding of objectivity to acknowledge the value-ladenness of risk assessment data.</p><p>At present, the value assumptions made by industry, government and private scientists during risk assessment go largely unnoticed yet have an effect on the outcome of regulatory decisions. Such assumptions must be recognized in order to ensure that the decisions made about the risks society face are not biased. This is particularly true in the case of biotechnology regulation. The development of the science of biotechnology has occurred concurrently with the development of the biotech industry creating the opportunity for industry-biased risk assessments.</p><p>It is possible to make changes to the existing regulatory regime in Canada in order to avoid some of the major problems associated with unrecognized value assumptions in risk assessment. A complete restructuring of the regime is unnecessary, however. Maintaining the current regulatory structure with some minor changes could address these problems. These changes include: creating an independent review board, making explicit that value assumptions are part of risk assessment in government advisory reports, and enhancing the role of regulators. Canadas regulatory system can better address the risks associated with biotechnology if it acknowledges that risk assessment is value-laden.</p>
|
17 |
Evaluation of Various Herbicides for Saw Greenbrier [Smilax bona-nox L.] and Southern Dewberry [Rubus trivialis Michx.] Control and Bermudagrass [Cynodon dactylon (L.) Pers.] Tolerance and Sharppod Morningglory [Ipomoea trichocarpa var. trichocarpa Ell.] Control in Roundup Ready Flex® and LibertyLink® Cotton SystemsJanak, Travis Wayne 2011 December 1900 (has links)
Field studies were conducted during 2006 and 2007 to evaluate control of saw greenbriar and southern dewberry by various pasture herbicides and to assess forage tolerance of Tifton 85 bermudagrass to these herbicides. Herbicides evaluated in each study included triclopyr, picloram, 2,4-D, fluroxypyr, dicamba, aminopyralid, metsulfuron methyl and various combinations of the above. Visual ratings were taken on each herbicide efficacy experiment. Visual evaluations of phytotoxicity, measurements of dry matter yield, and forage quality were quantified for each of the bermudagrass tolerance trials. Saw greenbriar was best controlled at approximately one year after treatment by triclopyr at 10.9% ae v/v with diesel as the carrier (88-98%), although the lower rate of triclopyr + diesel at 0.87% ae v/v + 5% v/v and triclopyr alone at 0.87% ae v/v provided 49 to 86% control. Triclopyr + fluroxypyr at 0.25% ai v/v + 0.086% ai v/v gave best control of southern dewberry in both years when applied as an individual plant treatment (IPT) six weeks after shredding. In general, shredding 45 days prior to herbicide application gave an advantage to southern dewberry control versus not shredding. In 2006, triclopyr + fluroxypyr (IPT) was the only treatment to decrease Tifton 85 dry matter yield at the first harvest, with no effect observed at the second harvest. In 2007, both broadcast treatments containing triclopyr + fluroxypyr and the IPT treatment of triclopyr decreased dry matter yield at the first harvest, with triclopyr (IPT) being the only treatment to lower dry matter yield at the second harvest. Field studies were also conducted in 2006 and 2007 to assess sharppod morningglory control in Roundup Ready Flex® and LibertyLink® cotton systems. Herbicides evaluated included glyphosate, glufosinate, prometryn, fluometuron, and diuron. Visual ratings of percent weed control and sharppod morningglory plant counts were taken to assess control. Prometryn at 1.8 kg ai ha⁻¹ and fluometuron at 1.8 kg ai ha⁻¹ provided significant preemergence control (33-81%) of seedling sharppod morningglory. All rates of glyphosate (1.06 and 1.54 kg ai ha⁻¹) and glufosinate (0.45 and 0.6 kg ai ha⁻¹) controlled sharppod morningglory from 55 to 100% at both application timings. The addition of diuron at 1.12 kg ai ha⁻¹ to glyphosate and glufosinate at the late season application enhanced sharppod morningglory control by 3 to 16%. Additionally, in both years, no reduction in cotton yield was observed in the morningglory infested treatment when compared to the weed free treatment.
|
18 |
基改種子專利到期對於基因改造作物產業之影響-以Monsanto抗嘉磷塞轉基因大豆為例 / The patent expiration of genetic modified seeds and its impact to the agricultural biotech industry- a case study of Monsanto’s roundup ready soybeans林家綺, Lin, Chia Chi Unknown Date (has links)
面對未來全球人口成長、可耕地減少等現象,生物技術在農業上的應用日益增加。其中,基因改造技術等基因層次相關的平臺應用技術更是提升農作物價值的關鍵—透過跨物種功能應用,大幅提升育種效率。自1996年基改作物商業化種植開始至今,美國都是全球最大種植國家,也是基改作物研發先驅國家。生技農業政策以及和基因改造作物有關法規之制訂使基改作物在美國蓬勃發展,尤其是專利保護對於種子產業之影響尤為深遠。專利權所提供的完善保護使大量資本進入種子產業,投入資源將農業生物技術應用於種子培育上,此舉也促成Monsanto等跨國農業生技公司之興起,主導全球基因改造作物之市場。
Monsanto將研發重心放在基改種子之研發,其在生技種子相關營業比重遠高於同業,同時,其投入特殊性狀之基改種子研發之回收遠高於其他公司之相同營業項目之投資報酬率。Monsanto積極藉由併購取得基因、基因轉殖技術以及種子種源。掌握關鍵基因、基因轉殖技術以及大量且優良種源使含有Monsanto轉殖基因作物在市場上佔有極大的比例。在美國,超過一半以上之主要作物種植面積為基因改造作物,尤其是基因改造大豆,佔大豆總種植面積之比例高達94%。市面上絕大多數基改大豆係Monsanto的抗嘉磷塞(RounupReady,RR1Y)基改大豆種子。藉由智慧財產保護策略,Monsanto並進一步限制RR1Y及其他基改作物之使用方式。
惟RR1Y專利將在2014年到期,農民可在2014年時留種種植基改大豆種子而不用每年購買種子,或購買學名(generic)抗嘉磷塞轉基因大豆種子。在美國所種植之大豆約有四成會外銷,而外銷國家基改作物規範法規是出口與否之關鍵。若未取得歐盟、中國等主要外銷國家基改作物主管機關之批准,呈交包括基因之轉殖植物對環境衝擊之風險評估、包含該基因之轉殖植物所製成食品之安全性評估等基改作物資訊,則抗嘉磷塞基因大豆無法進入該國糧食市場。然而,在目前美國農業生技基改作物相關規範下,學名基改種子廠必須在專利種子專利到期後,才能進行實驗及田間試驗,呈交相關資料以符合基改作物主管機關之要求。透過建立學名基改作物快速獲得核准查驗登記之程序,允許學名廠依賴專利基改作物原廠之實驗及田間試驗資料以建立其學名基改作物之安全性與性狀表現有效性,同時,允許學名基改作物在原基改作物開發廠專利期滿前即可開始進行試驗,可以使學名抗嘉磷塞大豆種子以及其他學名基改種子能在原專利基改作物種子專利到期後順利進入市場,促使基改作物種子價格競爭,並對於專利基改作物研發公司進行適度之補償,以促進產業發展。 / The development of new technologies in plant breeding has led to improvements in the efficiency scientists produce improved plant varieties. Genetic modification is among the developments that support plant breeding. The introduction of genetically modified crops has revolutionized the agriculture industry. With patent protection available on GM traits, varieties and other aspects of seed production, private R&D investments in the seed industry have increased tremendously. Monsanto has been the leading company in investing agricultural biotechnology and has obtained a dominant position in the GM traits found in soybeans, cotton, corn and other commercialized crops. Currently, over 90 percent of soybeans planted in the United States were herbicide-resistant, with Monsanto’s Roundup Ready being the dominant soybeans planted.
In 2014, however, the agriculture industry will be facing the expiration of a patent for Roundup Ready soybeans. Despiate the fact that the patent expiration date is approaching, the agricultural biotech industry has no guideline in place to tell its players exactly how to transition seamlessly from patent monopolies to generic competition. The transition problem is espectially significant for soybeans exported to oversea markets as more than 40 percent of the soybeans grown in the U.S. are exported. In order for those soybeans to be accepted in the grain channel, regulatory approvals are required in countries that import soybeans.
Obtaining data, which includes scitific data on the trait being developed, for regulatory approvals can take years to complete. If a generic trait is to reach market immediately after the original trait go off patent, the data generation process should begin before patent expiration. A Hatch-Waxman type patent infringement defense for activities necessary to obtain regulatory approvals for biotech traits can ensure that seed companies have sufficient time to obtain registrations for a generic Roundup Ready trait or other generic traits. Current legislation should be modified to adequately oversee the transition to the generic use of genetically modified crops and, in the mean time, ensure the availability of generic modified crops.
|
Page generated in 0.0297 seconds