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1.
The association of culm anatomy with lodging susceptibility in modern spring wheat genotypes 总被引：1，自引：0，他引：1
Selection for lodging resistant cultivars in cereal breeding programs is difficult due to the challenge of screening for this
trait under natural field conditions. The identification of easily measurable culm traits related to lodging resistance would
simplify the selection process. The present study was conducted to determine if differences in culm anatomy exist among modern
wheat genotypes differing in lodging susceptibility, and to determine the association between culm characters and lodging.
From a 2-year field study conducted in Edmonton, Alberta, 13 spring wheat cultivars were chosen based on predetermined susceptibility
to artificially induced lodging. Morphological and anatomical culm measurements were made visually and with an environmental
scanning electron microscope. Genotypes differed (P < 0.05) for plant height, number of internodes per culm, basal internode length and diameter, culm wall thickness and the
number of vascular bundles, but not for adventitious root frequency, lumen diameter or sclerenchyma ring thickness. Mean genotype
field scores for artificially induced lodging were correlated (P < 0.05) with plant height (r= 0.51) and the length of the fourth basal internode (r= 0.51). Short, wide basal internodes and thick culm walls were characteristic of three lodging tolerant genotypes: Kohika,
Sapphire and Olso. Nevertheless, despite such apparent genotype specific association between culm anatomy and field lodging,
general applicable associations were not observed for most traits. The most practical and easily selectable trait for lodging
resistance within a wheat breeding program remains plant height.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
烟草组织的环境扫描电镜观察 总被引：1，自引：0，他引：1
以烟草的不同组织为材料,采用改进的环境扫描电镜(ESEM)技术,对烟草的叶表皮、腺毛、花表皮和种子表皮微形态进行了显微观察及拍照。结果表明,改良的环境扫描电镜技术分辨率更高,能更真实地呈现组织的结构特点。同时发现烟草不同组织间细胞形态存在较大差异,一些基因的表达差异也能影响细胞的特征,这为转基因植株的微观性状描述提供了新的研究途径。 相似文献
3.
4.
An elemental chlorine-free (ECF)-bleached soft-wood kraft pulp was treated first with a carboxymethyl cellulose (CMC, degree
of substitution 0.3, 1% on pulp) and then with alkyltrimethylammonium bromides (alkyl chain lengths of C10 to C16). Surprisingly, the treatment with dodecyltrimethylammonium bromide (C12TAB) markedly increased the internal and tensile strengths of the handsheets prepared from the modified pulp. Environmental
scanning electron microscopy (ESEM) showed that these properties could be partly explained by the “rope/gum-like” bridges
that were formed between the fibers. 相似文献
5.
叙述了环境扫描电子显微镜（ESEM）在阻燃纤维板表征分析中的应用现状,使用ESEM对阻燃纤维板进行表征分析。 相似文献
6.
《Journal of Cereal Science》2014,59(3):457-464
Eleven maize landraces were evaluated for pozole quality. The microstructural, thermal and rheological properties of annealed starch granules determine most of the quality of pozole. Annealed starch in traditional nixtamalisation has an important role in increasing gelatinisation onset (To), peak (Tp) and final (Tf) temperatures; peak, setback and final viscosity as well as the stability of the starch granule, all of which significantly affect pozole quality. Annealed starch in Cacahuacintle nixtamal (pozole end-use) increased temperatures To, Tp and Tf by >5.2, >3.8 and >4.1 °C respectively, and narrowed the range Tf − To from 13.78 to 12.62 °C. The enthalpy was reduced from 6.76 to 5.85 J/g, while the nixtamal starch in tortilla maize landraces presented fewer annealing effects. The annealing effect in nixtamal starch seems to stabilize the starch granules and avoid their collapse, compared to native starch, as shown by the X-ray diffraction peak intensity and pattern that is similar to unprocessed maize. Starch in nixtamal changes from Type A to Type V pattern in pozole. Kernel physical parameters, although important, affected the quality to a lesser extent, with the exception of the flotation index. Cacahuacintle maize landrace showed the best quality and yield as well as a short pozole cooking time. 相似文献
7.
对菜豆7个品种和小莱豆、绿豆、小豆和长豇豆各1个品种的花粉进行了环境扫描电镜观察,对观测到的12个亚显微形态性状用SPSS聚类分析进行数量分类学研究。结果表明:11份花粉都呈近球形,花粉粒大小在所观察的材料间有较大差异。品种间在花粉的萌发器官和外壁纹饰方面有一定的差异,长豇豆花粉萌发器官略凹入花粉内,其他材料的花粉其萌发器官均明显外凸;菜豆和小莱豆花粉萌发器表面光滑,而绿豆、小豆和长豇豆萌发器表面皱缩,并有明显突起物;菜豆和小莱豆花粉外壁呈网状,而绿豆、小豆和长豇豆花粉外壁呈穴网状。Q型分析可以将供试材料在系数L1=0.188水平上分为菜豆和小莱豆、绿豆、小豆和长豇豆四大类,小莱豆与菜豆的亲缘关系较近。 相似文献
8.
为研究柞栎象(Curculio dentipes)寄主定位机制,利用环境扫描电镜对柞栎象触角形态、感受器的类型及分布特点等进行了观察。结果表明:柞栎象触角上有感受器5种类型10个亚型,分别为:刺形感受器2个亚型、毛形感受器4个亚型、锥形感受器、齿形感受器2个亚型和腔形感受器。柞栎象雌雄成虫触角性二型不明显,很难作为形态上性别鉴定的可靠依据。雄虫触角感受器数量多于雌虫,但差异不显著。柞栎象触角感受器从基部至端部(柄节至棒节第4亚节)有明显的分化趋势。 相似文献
9.
苹果属观赏海棠品种花粉形态及分类研究 总被引：10，自引：0，他引：10
采用环境扫描电镜观察山荆子等17个苹果属原生种及'道格'等25个观赏海棠品种的花粉形态特征,采用类平均法（UPGMA）进行聚类分析,探讨其花粉的主要特征及差异,研究亲缘关系及类群。结果表明,苹果属植物花粉为N3P4C5型,呈两侧对称的长球形或超长球形,赤道面具3条孔沟,沿极轴方向延伸至两极,萌发沟内有内孔,花粉表面为条状纹饰,有穿孔;各种或品种间花粉粒大小及外壁纹饰差异明显。聚类分析表明,佛罗伦萨海棠等2个苹果属原生种以及'罗宾逊'等7个观赏海棠品种聚为第一类群;山荆子等9个苹果属原生种以及'霍巴'等3个观赏海棠品种聚为第二类群;赛威士苹果等4个苹果属原生种以及'道格'等1个观赏海棠品种聚为第三类群;野香海棠等2个苹果属原生种以及'凯尔斯'等14个观赏海棠品种聚为第四类群。25个观赏海棠品种起源于北美洲基因中心,并通过与欧洲、亚洲基因中心的苹果种间杂交形成亲缘关系复杂的品种。 相似文献
10.
利用环境扫描电子显微镜原位监测木材的断裂过程 总被引：5，自引：0，他引：5
在环境扫描电子显微镜样品舱内低真空模式下,对鱼鳞云杉微切片试样进行原位纵向拉伸试验。并对原位监测裂纹的产生、开裂及扩展的全过程进行研究,拍摄了整个过程的录像并存储了相应的图片,同时记录了载荷——时间曲线。分析了径向面(LR面)裂纹扩展系统的断裂路径和机理。 相似文献