952 resultados para Leafworm cotton


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ZnO nanostructures were deposited on flexible polymer sheet and cotton fabrics at room temperature by activated reactive evaporation. Room-temperature photoluminescence spectrum of ZnO nanostructured film exhibited a week intrinsic UV emission and a strong broad yellow-orange visible emission. TEM and HRTEM studies show that the grown nanostructures are crystalline in nature and their growth direction was indentified to be along [002]. ZnO nanostructures grown on the copper-coated flexible polymer sheets exhibited stable field-emissio characteristics with a threshold voltage of 2.74 V/mu m (250 mu A) and a very large field enhancement factor (beta) of 23,213. Cotton fabric coated with ZnO nanostructures show an excellent antimicrobial activity against Staphylococcus aureus bacteria (Gram positive), and similar to 73% reduction in the bacterial population is achieved compared to uncoated fabrics after 4 h in viability. Using a shadow mask technique, we also selectively deposited the nanostructures at room temperature on polymer substrates.

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Diesel spills contaminate aquatic and terrestrial environments. To prevent the environmental and health risks, the remediation needs to be advanced. Bioremediation, i.e., degradation by microbes, is one of the suitable methods for cleaning diesel contamination. In monitored natural attenuation technique are natural processes in situ combined, including bioremediation, volatilization, sorption, dilution and dispersion. Soil bacteria are capable of adapting to degrade environmental pollutants, but in addition, some soil types may have indigenous bacteria that are naturally suitable for degradation. The objectives for this work were (1) to find a feasible and economical technique to remediate oil spilled into Baltic Sea water and (2) to bioremediate soil contaminated by diesel oil. Moreover, the aim was (3) to study the potential for natural attenuation and the indigenous bacteria in soil, and possible adaptation to degrade diesel hydrocarbons. In the aquatic environment, the study concentrated on diesel oil sorption to cotton grass fiber, a natural by-product of peat harvesting. The impact of diesel pollution was followed in bacteria, phytoplankton and mussels. In a terrestrial environment, the focus was to compare the methods of enhanced biodegradation (biostimulation and bioaugmentation), and to study natural attenuation of oil hydrocarbons in different soil types and the effect that a history of previous contamination may have on the bioremediation potential. (1) In the aquatic environment, rapid removal of diesel oil was significant for survival of tested species and thereby diversity maintained. Cotton grass not only absorbed the diesel but also benefited the bacterial growth by providing a large colonizable surface area and hence oil-microbe contact area. Therefore use of this method would enhance bioremediation of diesel spills. (2) Biostimulation enhances bioremediation, and (3) indigenous diesel-degrading bacteria are present in boreal environments, so microbial inocula are not always needed. In the terrestrial environment experiments, the combination of aeration and addition of slowly released nitrogen advanced the oil hydrocarbon degradation. Previous contamination of soil gives the bacterial community the potential for rapid adaptation and efficient degradation of the same type of contaminant. When the freshly contaminated site needs addition of diesel degraders, previously contaminated and remediated soil could be used as a bacterial inoculum. Another choice of inoculum could be conifer forest soil, which provides a plentiful population of degraders, and based on the present results, could be considered as a safe non-polluted inoculum. According to the findings in this thesis, bioremediation (microbial degradation) and monitored natural attenuation (microbial, physical and chemical degradation) are both suitable techniques for remediation of diesel-contaminated sites in Finland.

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This study concerns the effect of duration of load increment (up to 24 h) on the consolidation properties of expansive black cotton soil (liquid limit = 81%) and nonexpansive kaolinite (liquid limit = 49%). It indicates that the amount and rate of compression are not noticeably affected by the duration of loading for a standard sample of 25 mm in height and 76.2 mm in diameter with double drainage. Hence, the compression index and coefficient of consolidation can be obtained with reasonable accuracy even if the duration of each load increment is as short as 4 h. The secondary compression coefficient (C-alpha epsilon) for kaolinite can be obtained for any pressure range with 1/2 h of loading, which, however, requires 4 h for black cotton soil. This is because primary consolidation is completed early in the case of kaolinite. The paper proves that the conventional consolidation test can be carried out with much shorter duration of loading (less than 4 h) than the standard specification of 24 h or more even for remolded fine-grained soils.

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ZnO nanostructured films were deposited at room temperature on glass substrates and cotton fabrics by activated reactive evaporation in a single step without using metal catalyst or templates. Morphological observation has shown that the nanostructured film contains seaurchin-like structures, and this seaurchin containing large number of randomly grown ZnO nanoneedles. Microstructural analysis revealed the single crystalline nature of the grown nanoneedles and their growth direction was indentified to be along [0002]. PL spectrum of nanostructured films has shown a relatively weak near-band-edge emission peak at 380 nm, and a significant broad peak at 557 nm due to the oxygen vacancy-related emission. ZnO nanostructured films grown on glass substrates and cotton fabrics have shown good photocatalytic activity against rhodamine B.

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The paper brings out the role of calcium carbonate (CaCO3) on the volume change behaviour of natural black cotton soil with 1N sulfuric acid (H2SO4) as pore fluid. Natural black cotton soil contained predominantly montmorillonite [Ca0.2(Al,Mg)2Si4 O10 (OH)2 .4H2O] along with other minerals such as amesite [(Mg Fe)2 Al (Si Al)2 O5 (OH)4], kalsilite [KAlSiO4] and quartz [SiO2]. The calcitic soil, reacted with H2SO4 during consolidation testing, showed the presence of the new mineral yavapaiite [K Fe(SO4)2]. Consequently, the carbonate soil treated with 1N H2SO4 led to higher swell at seating load and more compression upon loading than the soil with no carbonate. The swelling increased with increase in the amount of carbonate present in the soil.

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Fly ashes are used to improve the properties of expansive soils. The paper brings out the effect of two different fly ashes containig different lime contents on shrinkage and swelling behaviour of expansive Indian Black cotton soil. Since the specific gravities of the fly ashes are considerably different,Void ratio at shrinkage limit and % of swelling are used to describe the shrinkage and swell behaviour of soils. Both fly ashes increase the shrinkage void ratio and decrease the % swell of the soil. While high lime fly ash is more effective in increasing the shrinkage void ratio, low lime flyash is more effective in reducing the swelling. Lime content which causes floculation of soil particle, is responsible for the differences.

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Uma das maiores atividades humanas que gera impacto ao meio ambiente é o setor de transportes automotores, especialmente veículos que utilizam óleo diesel mineral como forma de combustível. Independente do conforto ou objetivos que levem a utilização deste tipo de transporte, estes produzem emissões que contém diversos tipos de poluentes atmosféricos. A substituição de óleo diesel mineral pelo biodiesel vegetal, vem se apresentando como uma alternativa para este setor, especialmente para o Brasil, que com base em sua imensa biodiversidade com plantas oleaginosas deverá se constituir em um dos maoires produtores mundiais de biodiesel vegetal. Este trabalho apresenta um estudo comparativo entre três tipos de oleaginosas (soja, algodão e mamona) e uma msitura binária v/v soja e algodão. Os resultados obtidos neste estudo foram comparados as especificações definidas pelas normas: Brasileira (RANP 07/2008), Européia (EN/14214) e Americana (ASTM D-6751). Entre todas as amostras estudadas, o óleo de mamona não atende algumas propiedades físico-químicas das normas em questão. As amostras de biodiesel de soja e algodão, individualmente e combinadas, com caracteristicas, aplicações, zoneamento agroclimático e sazonalidade de produção regionalmente diferente apresentam propiedades físico-químicas semelhantes, podendo ser considerada uma fonte renovavél de energia.

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Atualmente, o Brasil se apresenta como um grande produtor agrícola mundial com finalidade alimentícia e bioenergética. Ano a ano recordes de produção são batidos pelo setor agropecuário. Por outro lado, tem-se uma perspectiva de problemas alimentícios e energéticos no mundo, em especial no continente africano onde muitos vivem na miséria e na fome. Neste contexto, esta dissertação de mestrado apresenta uma proposta para a análise da dinâmica espaço-temporal de culturas agrícolas empregando os conceitos e instrumentos da Geomática em busca do desenvolvimento sustentável. Desenvolveu-se uma metodologia para a geração de indicadores da produção agrícola em diferentes níveis da estrutura territorial brasileira que permite a apresentação sintética, por meio de cartogramas e animações digitais, das dinâmicas espacial e espaço-temporal das principais culturas. Para isto foi criada uma base de dados da produção das principais culturas, desenvolvidos indicadores que representem a dinâmica espacial da produção agrícola e desenvolvidas ferramentas de apresentação destes indicadores através da dinâmica espaço-temporal. Finalmente, foram relacionadas as áreas voltadas à produção de alimentos e de expansão agrícola para a bioenergia (etanol e óleo de palma). Pretende-se, através deste trabalho, contribuir na tomada de decisão com ferramentas de visualização da realidade agropecuária brasileira. O trabalho estabelece ligações com os zoneamentos agroecológicos, os instrumentos de segurança alimentar e a pegada ecológica, com a apresentação da produção agrícola das culturas como cana-de-açúcar, milho, soja, palma de óleo e algodão.

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Os orifícios de acesso aos parafusos de retenção devem ser preenchidos para que o parafuso não seja danificado caso seja necessária a remoção da prótese. Dentre os materiais mais utilizados estão o algodão, a fita de politetrafluoretileno e a guta percha. O objetivo deste estudo é avaliar a formação de biofilme de Candida albicans nos materiais anteriormente descritos, buscando estabelecer um parâmetro que contribua para a escolha do tipo de material mais adequado a ser utilizado clinicamente. Foram utilizados UCLAs, análogos e parafusos sextavados, todos de titânio. Os conjuntos foram montados com torque de 32N. Os materiais foram condensados no interior dos UCLAs e colocados em meio de cultura com uma suspensão de 3x106 células/ml de Candida albicans. O sistema foi armazenado à 37C com agitação, por 15 dias e o meio foi renovado a cada 48 horas. A quantificação de biofilme foi realizada pelo ensaio de MTT e leitura à 490nm, resultando em diferentes valores de densidade óptica. A normalidade (p=0,304 - Kolmogorov-Smirnov) e a igualdade de variâncias (p=0,721 - Scheffe) foram testadas primeiramente. O teste de análise de variância demonstrou diferença significativa entre os grupos (p<0,001) e com o Holm-Sidak foi observada diferença significativa entre os grupos algodão e guta (p<0,05) e algodão e fita de politetrafluoetileno (p<0,05); não houve diferença significativa entre os grupos guta e fita de politatrafluoretileno (p>0,05), apesar dos valores da fita de politetrafluoetileno terem sido maiores. Considerando-se as limitações deste estudo in vitro, podemos concluir que tanto a guta-percha quanto a fita de politetrafluoretileno apresentaram menor formação de biofilme, não havendo diferença estatisticamente significativa entre os materiais. O algodão apresentou um nível de formação de biofilme significativamente maior que a fita de politetrafluoretileno e a guta percha. Diante disso, serão necessários novos estudos para confirmar as limitações que este tipo de material pode apresentar quando usado como material de preenchimento do acesso do parafuso da prótese sobre implante.

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O objetivo desse estudo foi comparar a capacidade de dois materiais restauradores em prevenir a descoloração coronária causada pela minociclina como medicação intracanal e propor uma técnica de fácil implementação para encorajar o uso da pasta tri-antibiótica para desinfecção do sistema de canais radiculares durante procedimentos de regeneração pulpar sem perda estética. Cem dentes foram selecionados, seus canais radiculares foram instrumentados e divididos em quatro grupos de acordo com o tratamento dentinário utilizado: Grupo OB- Agente adesivo OptiBond All-In-One (KERR); Grupo U200- Cimento resinoso auto-condicionante e auto adesivo RelyX U200 (3M ESPE); Grupo MIN- Sem revestimento; Grupo CN- Sem revestimento (controle negativo). Em todos os grupos, com exceção do CN, foi utilizada pasta de minociclina como medicação intracanal coberta por uma bolinha de algodão e vedados com restauração provisória. As medições de cor foram realizadas com um espectrofotômetro no início do estudo (T0), e 7(T7), 14 (T14), 21 (T21) e 28 dias (T28) pós-minociclina. Os resultados obtidos foram submetidos à análise estatística. As diferenças de cor (E*) foram crescentes nos grupos CN, OB, U200 e MIN, respectivamente. A diferença de luminosidade (L*) foi também crescente nos grupos CN, OB, U200 e MIN, respectivamente. Houve diferença significante entre os grupos MIN e CN, e entre os grupos MIN e U200 (p<0,05). O eixo amarelo-azul (b*) não apresentou alteração de cor significante (p>0,05). Uma alteração de cor significante no eixo vermelho-verde (a*) foi observada no grupo MIN em relação ao grupo CN (p<0,05). Portanto, conclui-se que a técnica foi fácil de ser implementada, ambos materiais reduziram a descoloração da coroa causada pela pasta de minociclina mas foram ineficazes em impedi-la completamente.

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This is the Irwell: Story of an industrial river document produced by the North West Water in 1979. This report is a leaflet format document. It focuses on the historical evolution of River Irwell, since it was “born” the river Irwell, about three hundred million years ago when shallow seas covered most of south east Lancashire and Europe to present years. It looks at Irwell’s pollution, highlighting the Irwell’s lower stretches were some of the region was the most polluted due to the population growth and establishment of industrial activities i.e. Lancashire’s great cotton industry, breach and dye works, paper mills, tanneries, chemical and gas works. Wastes from these industries were discharged directly to the river, together with crude sewage from an ever increasing population. However over the years the condition of the Irwell was gradually improved.

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Long-term living resource monitoring programs are commonly conducted globally to evaluate trends and impacts of environmental change and management actions. For example, the Woods Hole bottom trawl survey has been conducted since 1963 providing critical information on the biology and distribution of finfish and shellfish in the North Atlantic (Despres-Patango et al. 1988). Similarly in the Chesapeake Bay, the Maryland Department of Natural Resources (MDNR) Summer Blue Crab Trawl survey has been conducted continuously since 1977 providing management-relevant information on the abundance of this important commercial and recreational species. A key component of monitoring program design is standardization of methods over time to allow for a continuous, unbiased data set. However, complete standardization is not always possible where multiple vessels, captains, and crews are required to cover large geographic areas (Tyson et al. 2006). Of equal issue is technological advancement of gear which serves to increase capture efficiency or ease of use. Thus, to maintain consistency and facilitate interpretation of reported data in long-term datasets, it is imperative to understand and quantify the impacts of changes in gear and vessels on catch per unit of effort (CPUE). While vessel changes are inevitable due to ageing fleets and other factors, gear changes often reflect a decision to exploit technological advances. A prime example of this is the otter trawl, a common tool for fisheries monitoring and research worldwide. Historically, trawl nets were constructed of natural materials such as cotton and linen. However modern net construction consists of synthetic materials such as polyamide, polyester, polyethylene, and polypropylene (Nielson et. al. 1983). Over the past several decades, polyamide materials which will be referred to as nylon, has been a standard material used in otter trawl construction. These trawls are typically dipped into a latex coating for increased abrasion resistance, a process that is referred to as “green dipped.” More recently, polyethylene netting has become popular among living resource monitoring agencies. Polyethylene netting, commonly known as sapphire netting, consists of braided filaments that form a very durable material more resistant to abrasion than nylon. Additionally, sapphire netting allows for stronger knot strength during construction of the net further increasing the net’s durability and longevity. Also, sapphire absorbs less water with a specific gravity near 0.91 allowing the material to float as compared to nylon with specific gravity of 1.14 (Nielson et. al. 1983). This same property results in a light weight net which is more efficient in deployment, retrieval and fishing of the net, particularly when towing from small vessels. While there are many advantages to the sapphire netting, no comparative efficiency data is available for these two trawl net types. Traditional nylon netting has been used consistently for decades by the MDDNR to generate long term living resource data sets of great value. However, there is much interest in switching to the advanced materials. In addition, recent collaborative efforts between MDNR and NOAA’s Cooperative Oxford Laboratory (NOAA-COL) require using different vessels for trawling in support of joint projects. In order to continue collaborative programs, or change to more innovative netting materials, the influence of these changes must be demonstrated to be negligible or correction factors determined. Thus, the objective of this study was to examine the influence of trawl net type, vessel type, and their interaction on capture efficiency.

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1.以MS无机盐+B 5有机成分为基本培养基,附加2,4-D,KT,ZT等激素,以农艺性状良好,抗枯萎病的棉花品种“冀492”为材料,建立了愈伤组织诱导,体细胞胚胎发生和植株再生体系. 2.实验结果表明,2,4-D是诱导愈伤组织产生的促进因子,效果明显好于其它生长素类物质,但是随着培养基中2,4-D浓度的升高,愈伤组织状态也会变差,褐化严重,而且,附加O.lppm 2,4-D,O.lppm K T的培养基是较为合适的培养基.IAA,NAA对愈伤组织的诱导不十分理想,此外,愈伤组织的产生还同外植体,基因型和一些物理条件有关, 胚性愈伤组织的产生,需不断调节培养基中激素浓度,逐步降低2,4 -D浓度,并添加低浓度ZT,胚状体要在去除2,4-D的培养基上才能产生.虽然,2,4-D对于胚性愈伤组织的诱导是必须的,但是却抑制胚状体的发育. 3.培养基中硝态氮和氨态氮比例,激素浓度和种类,活性炭的添加,对于胚状体的萌发和成熟有重要影响,硝酸钾加倍,硝酸铵减半,并附加低浓度ABA和活性炭是胚状体诱导和成苗(去除ABA)的适宜培养基,而附加0.2ppm N A A,0.2ppm ZT和活性炭的M S2培养基是胚状体成熟的适宜培养基.通过对胚性愈伤组织的干燥处理,培养基中低浓度ABA和活性炭的添加,比较有效地抑制了畸形胚的产生,大大地提高了正常胚的比例. 4.对陆地棉“冀4 9 2”的下胚轴和子叶利用含Bt抗虫基因的根农杆菌(AgrobacterIIm tumefrens)进行了遗传转化研究,在筛选培养基上获得了大量生长旺盛的阳性愈伤组织,葡糖酸苷检测结果表明,大部分愈伤组织均有G us基因的表达. 5.通过花粉管通道法,进行了将含有Bt抗虫基因DNA的大肠杆菌质粒导入陆地棉“冀492”的实验,并收获了近1 0,000粒种子,为从大量种子中筛选出抗性种质材料,建立了卡那霉素田间初步筛选法. 6.利用活体压片和石蜡切片技术对体细胞胚胎发生过程和胚状体起源进行了观察,发现胚状体发生主要是通过类合子途径进行的,胚状体可能起源于单细胞. 7.通过对相同培养基上的非胚性愈伤组织,胚性愈伤组织和不同时期胚状体的可溶性蛋白SDS - PAGE电泳分析,发现16KD和50K D蛋白特异性地存在于胚性愈伤和各期胚状体中,该蛋白可作为胚性愈伤组织的筛选标记.对不同发育时期的愈伤组织进行了同工酶和可溶性蛋白的IE F/SD S-PA G E双向电泳分析,结果表明,不同发育时期的愈伤组织同工酶酶谱和可溶性蛋白电泳图谱之间具有较大的差别,分化前期的胚性愈伤组织酶的活性强,种类多,并且有新的蛋白斑点的出现,这些都可能与体细胞胚胎发生相关.

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本文通过根农杆菌(Agrobacterium tumfaciens)介导法分别将Signal和KDEL修饰的豇豆胰蛋白酶抑制剂(Cowpea trypsin inhibitor, CpTI)基因、豌豆外源凝集素(Pea lectin, P-Lec)和大豆Kunitz型胰蛋白酶抑制剂(Soybean Kunitz typsin inhibitor, SKTI)双价抗虫基因、雪花莲外源凝集素(Galanthus nivals agglutinin, GNA)基因以及高效复合启动子OM控制的苏云金杆菌(Bacillus thuringiensis, B.t.)杀虫毒蛋白基因导入了陆地棉(Gossypium hirsutum L.)栽培品种新陆早1号、新陆中2号、晋棉7号、冀合321、辽9和晋棉12号,并获得了大批转基因再生植株。 实验中对影响棉花转化和再生的一些条件进行了研究,从根农杆菌培养、棉花无菌苗的制备、转化操作和共培养等方面对转化条件进行了探讨;从激素配化、植物表达载体、外植体类型、基因型等方面对抗性愈伤组织的诱导进行了摸索;从激素、从碳源、培养容器、pH值、抗褐化剂及固化剂的选择等方面对影响植株再生的条件进行了优化。 本文开创性地采用嫁接代替移栽,从而极大地提高了转化植株定植成活率,缩短了缓苗时间并增加了转化植株当代的繁殖系数。 在建立了一套较为高效的陆地棉转化及再生系统基础上,本文还进行了其它转化方式和转化体系的初步探讨。利用棉花幼嫩种子无菌苗下胚轴作为外植体,通过改变愈伤组织诱导培养基配方面提高胚性愈伤组织的诱导频率,进而得到更多的体细胞胚状和再生植株,缩短再生周期;尝试用胚性愈伤组织作为外植体的根农杆菌介导法转化,确定了一些与转化有关的条件;建立了一套棉花茎尖培养程序,为运用基因枪法轰击棉花茎尖分生组织或用根农杆菌直接转化茎尖分生组织,以克服根农杆菌转化棉花时体胚发生的基因型局限开辟了一条新途径。 本文还建立了一种快速鉴定转化植株后代的方法。这一简便方法还有助于进行转基因棉纯合系的筛选以及外源基因的遗传稳定性研究。 转基因植株经Npt-II ELISA、PCR、PCR Southern 检测证明外源抗虫基因CpTI、SKTI、P-lec、GNA以及B.t.基因已存在于转化植株基因组内。修饰的CpTI转基因植株抗棉铃虫(Heliothis armigera Hubner)试验结果表明,其杀虫效果显著优于前期未修饰的CpTI转化植株。P-lec和SKTI双价转基因植株抗棉铃虫试验结果表明,转基因植株对棉铃虫幼虫具有较强的杀虫活力。 目前,已获得转以上抗虫基因棉花T1代植株。为今后进一步将植物基因工程技术应用于棉花遗传改良打下了基础。

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将pBIN35S-mGFP4质粒转入受体菌DH5α中,扩繁后提取纯化质粒DNA,待棉花盛花期时,用花粉管通道转化方法将其注射到授粉24小时左右的子房中。在被检测的950个发育10~20天左右的幼胚中,发现七个幼胚在蓝光(460~490nm)激发下发出绿色荧光,而对照发出程度不同的红色荧光。将收获的“转化种子”浸泡萌发得到生长5~6天的黄化无菌苗,在200粒种子来源的无菌苗中,检出两棵转化植株。在紫外光照射灯下转化植株发出绿色荧光,其叶片和下胚轴横切面在蓝光激发下也与对照明显不同。PCR及Southern blotting结果均证实转化植株的真实性,从而为花粉管通道转化方法的可行性提供了直接可靠的细胞及分子生物学证据。 将GFPmut1质粒的gfp通过一端平接一端粘接后重组到pBI121的BamH1和Sal1限制性酶切位点从而代替GUS基因,然后将新的重组质粒用三亲交配法转入到LBA4404菌株中得到双元载体,用于棉花下胚轴切段的转化。结果表明,gfp象gus一样可作为报告基因用于农杆菌介导的棉花转化。在对筛选培养基上生长的“抗性愈伤”进一步进行报告基因检测时,只需手持紫外灯就可以检出GFP阳性愈伤,大大减少了工作量和试验费用。 另外,在进行农杆菌转化前的棉花卡那霉素敏感性实验中发现,卡那霉素对棉花下胚轴的愈伤组织形成和增殖均有明显的抑制作用,随其浓度的增加,愈伤组织形成的频率降低,增殖的倍数减小;当浓度增加到100mg/L时,愈伤组织严重褐化,其正常生长受到完全抑制;下胚轴形态学上端切段较下端更易受卡那霉素的影响。