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排序方式: 共有16条查询结果,搜索用时 15 毫秒
1.
Summary Intervarietal crosses in watermelon, Citrullus lanatus (Thunb.) Mansf., involving six parents with black (J18-1 and J 75), brown (J56-1 and N.H. Midget), red (Bykovski-199) or light cream (Red Nectar) seed-coat colour were made. Parents, F1, F2 and backcross populations were evaluated for their phenotypic expressions with regard to the seed-coat colours involved. Black colour was monogenically dominant over brown light cream and red colour of seed-coat separately or independently. Red colour was dominant over light cream colour of seed-coat by a single pair of genes. The light cream colour was recessive to the brown seed-coat colour of watermelon where a single pair of genes was involved.  相似文献   
2.
Enzymes and chelating agent in cotton pretreatment   总被引:6,自引:0,他引:6  
Desized cotton fabric and cotton seed-coat fragments (impurities) have been treated with commercial cellulase (Celluclast 1.5 L), hemicellulase–pectinase (Viscozyme 120 L) and xylanase (Pulpzyme HC) enzymes. Seed-coat fragments hydrolyzed much faster than the cotton fabric itself. This relative difference in hydrolysis rates makes possible a direct enzymatic removal of seed-coat fragments from desized cotton fabric. Addition of chelating agents such as ethylenediamine-tetra-acetic acid (EDTA) markedly enhanced the directed enzyme action. Pretreatments carried out in acidic solution at pH 5 increased the lightness of seed-coat fragments, contrary to the samples treated in neutral medium at pH 7. Alkaline scouring resulted in darker seed-coat fragments except for the samples pretreated with Pulpzyme HC plus EDTA. This effect is similar to that observed in the biobleaching process in pulp and paper industry.  相似文献   
3.
Seed morphology in Veronica L. (Scrophulariaceae) from south-west Spain   总被引:1,自引:0,他引:1  
Seeds of 12 species of Veronica from south-west Spain were examined with the scanning electron microscope and stereomicroscope. Based on seed shape, colour, cell shape and surface ornamentation, seven morphological types are recognized. Seeds of the different types are described, illustrated and compared. The distribution of seed types among taxa is given. A key to distinguish the different species or groups of species is provided.  相似文献   
4.
Herbert Straka 《Grana》2013,52(2):157-158
A plea for using the terms “sculpture” and “structure” as defined by Potonié is discussed.  相似文献   
5.
In order to examine the systematic application of seed-coat microsculpturing in Isatis, seed surfaces of 23 species (41 populations) in four genera of tribe Isatideae were examined using scanning electron microscopy (SEM). Eight types of basic ornamentation patterns were recognized among the studied specimens. Of these, the reticulate–areolate type was the most common and was found in the genera Isatis, Pachypterygium, Samerari and Tauscheria and 15 species (e.g., I. cappodocica, I. kotschyana and I. tinctoria). The reticulate type, the second most frequent, occurred in 7 species while other types each were represented by only one or 2 species. Although different populations of a given species show similar seed-surface sculpturing in most cases, in some polymorphic species like I. cappadocica and I. kotschyana these patterns were variable among populations. To some extent the variation corresponds to infraspecific taxa for some species, but the differences are not significant enough to be useful in the delimitation of the subspecies recognized by previous workers. Moreover, seed-coat characters do not support the separation of genera Isatis, Pachypterygium, Sameraria and Tauscheria.  相似文献   
6.
In this paper, the shape and size modification of recent pollen grains have been studied. 63 species of recent pollen grains that belongs to 55 genera, 26 families were observed before and after the acetolysis treatment with LM. The length of polar axis and equatorial axis and the thickness of exine were measured from about 20 pollen grains for each species (the thickness of exine were only measured for acetolysed pollen grains). The significance of shape and size modification was examined with the statistical method "ttest". From this investigati0n it can be concluded that: The pollen modification in size and shape 'was related to aperture type, pollen size, wall thickness and sculpture depth. Pantoporate, spheroidal pollens and small perporlate pollens usually change little in there size and shape after acetolysis. The size of colpate pollens was generally increased, or their shape changed. The size or shape change usually got bigger as the pollen size, wall thickness and sculpture depth became bigger and bigger. Oblate pollens were apter to change their size and shape than prolate pollens. The P/E ratio of most colpate pollens became a little bigger after acetolysis.  相似文献   
7.
Summary Microfacies-based provenance analysis of Roman mosaics found in Southern Bavaria near Augsburg indicates the use of Mesozoic carbonates and sandstones occurring as boulders within Pleistocene and Holocene deposits near to the mosaic sites. In addition, local allochthonous Late Jurassic ooid-peloid grainstones were used for the fabrication of white tesserae. Microfacies criteria provide a means for evaluating the original location of sculptures as demonstrated by the study of the head of a Roman Goddess made of Alpine Late Triassic limestone.  相似文献   
8.
Fungal enzyme preparations from Phanerochaete chrysosporium, Aspergillus oryzae, Aspergillus giganteus and Trichoderma virens, produced by solid-state fermentation (SSF) on cotton seed-coat fragment waste as substrate and enzyme inducer were investigated in biopreparation of cotton fabric. Cotton seed-coat fragment is rich in lignin, cellulose and hemicelluloses, therefore enzyme complexes produced by target fungi on such a substrate can be used effectively to degrade impurities in cotton fabrics during biopreparation. Activities of extracellular hydrolytic and ligninolytic enzymes were determined from the SSF extract materials. The potential of the hydrolytic and accompanying oxidative enzymes in the whole SSF cultures was exploited in degradation of seed-coat fragments and other coloring materials of greige cotton fabric. Enzyme assays indicated that many extracellular enzymes have been produced under these conditions including both hydrolytic and oxidative enzymes. A. oryzae NRRL 3485 produced significantly higher amounts of both hydrolytic and oxidative enzymes than other tested fungi. Best results in removal of seed-coat fragments from cotton fabric were obtained by P. chrysosporium NCAIM (=ATCC 34541), P. chrysosporium VKM F-1767 and A. oryzae NRRL 3485 SSF enzyme complexes.  相似文献   
9.
本文对中国东北牛儿苗科(Geraniaceae)二属(太阳花属Erodium, 老鹳草属(Geranium)计14种(species)1变种(Variety)和1变型(form)植物的种皮亚显微结构(SEM)及种子形态进行了研究.结果表明, 太阳花属与老鹳草属植物无论从种子形状, 长宽比, 还是种皮初级雕纹及次级雕纹形态都表现出明显差异。在老鹤草属下种及种下等级的鉴定和划分上, 种皮微形态及种子形态特征提供了大量有价值的信息。  相似文献   
10.
Studied in this work was seed morphology of the genus Plantago (2 subgenera, 8 sections, 17 species and 1 variety )in China. The sculpture was observed under scanning election microscope. Four forms of seed morphology are recognized as follows: (1)Multi-angular type: seeds are variously angulate, yellow-brown or black, 6-30 in a fruit; seed-coat sculpture ranges from reticulate to papillate. It occurs in Subgen. Plantago Sect. Polyneuron: P. scheideri, P. denstflorus, P. major, P. hostifolia, P. asiatica, P. erosa and P. centralis. (2) Navicular type: seeds are navicular, yellow, brown to black, 2 in a fruit; seed-coat sculpture is reticulate. It was found in Subgen. Plantago Sect. Novorbis: P. virginica; Sect. Arnoglossum: P. lanceolata; Sect. Leucopsyllium: P. minuta, P. lessingii and P. aristata and Subgen. Psyllium Sect. Psyllium: P. indica. (3)Ovoid type: seeds are long-ovoid, yellow-brown, black and lustrous. Seed-coat sculpture scali-ratiform. P. maxima in Subgen. Plantago Sect. Lamprosantha belongs to this type. (4)Recti-circular type: seeds are recti-circular, yellow-brown, black, 1-2 or 4-5 in a fruit; seed-coat sculpture is reticulate and papillate. It was found in P. maritima var. salsa of Subgen. Plantago Sect. Coronopus and P. depressa, P. camtschatica and P. arachnoidea of Sect. Mesembrynia. The seed morphology and seed-coat sculture exhibit specific characters, by which some of confused species can be clarified and a new species, P. densiflorus J. Z. Liu. is established. The present author’s seed morphology classification is in accordance with Pilger’s systemof the genus, which was established using other features.  相似文献   
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