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小麦与珍珠栗远缘杂交的受精作用和胚胎发育 总被引:1,自引:0,他引:1
对波斯小麦、“中国春”小麦与珍珠栗远缘杂交的受精作用和胚胎发育进行了研究。珍珠栗花粉管能在小麦柱头上萌发,并且有多个花粉管进入花柱及胚囊。波斯小麦已授粉的207个子房中,11.11%既形成胚又形成胚乳,7.25%中形成胚,而1.93%只形成胚乳,在这个杂交中受精率和成胚率分别为20.29%和18.36%。“中国春”小麦已授粉的167个子房中,相应数字是2.99%、5.99%、0、8.98%和8.9 相似文献
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娑罗子为七叶树科植物欧洲七叶树(Aesculus hippocastannum)、日本七叶树(Aesculus turbinata Blume)和中国天师栗(Aesculus Wilsonii Rehd)的果实或种子。欧洲七叶树,又名欧马栗(horse chestnut),其种子和幼枝的外皮可入药,在欧洲应用广泛,早在18世纪即用于解热,19世纪后期可用于治疗痔疮。七叶皂苷是从娑罗子(七叶树种子)中提取的主要活性成分,属于三萜皂苷类药物。它具有抗渗、消肿、改善血液循环、增加静脉张力、抑制胃排空、清除活性氧和抗肿瘤作用。临床上可广泛应用于慢性静脉功能不全,痔疮、水肿、哮喘等。本文对七叶皂苷的药理作用及其临床应用进行综述。 相似文献
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采用聚丙烯酸胺凝胶电泳方法,从栗疫病菌Cryphonectriaparasitica的18种酶体系中筛选到9种分辨率高的同工酶。对同工酶的检测结果表明,在中国的北京、辽宁、江西、福建及意大利、美国、日本共7个群体的115个栗疫病菌菌株中,多酚氧化酶(PPO)、过氧化物酶(POX)、细胞色素氧化酶(CCO)、乙醇脱氢酶(ADH)、超氧化物歧化酶(SOD)为单态性;α-酯酶(α-EST)、β-酯酶(β-EST)、苹果酸脱氢酶(MDH)、苹果酸酶(ME)为多态性,分别具有10、7、3、3种电泳表现型。通过9种同工酶的凝胶电泳分析,对栗疫病菌的群体结构进行了比较。中国地区4个群体间的遗传相似性较大,与美国、意大利、日本群体间的相似性较小;美国、意大利群体间的遗传相似性较大,且它们与日本群体间的相似性大于与中国各群体间的相似性,这一结果表明美国的栗疫苗可能是从日本传人的。病菌群体的遗传变异率为of60,其中83.1%由群体内的变异引起,16.9%由群体间的差异引起。群体间的基因流动值为246。 相似文献
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笔者经过多年的反复试验,并在桂林、天津两地推广应用,充分证明:银杏断胚根是有效的促根措施,也是培育壮苗,促进早实丰产的重要技术措施之一。 催芽之后,一般在胚根长1厘米以上时,及时在根颈以下2—3毫米处剪断发芽种子的胚根。 剪切部位对断胚根来说是至关重要的,如果在根颈以上剪切,会使这粒种子不能成苗,一定要在根颈以下剪 相似文献
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从世界栗属植物研究的现状看中国栗属资源保护的重要性 总被引:18,自引:1,他引:18
栗属(Castanea)植物世界上有7个种,广泛分布于北半球温带的广阔地域[1]。分布在亚洲的4个种:中国板栗(C.mollissimaBI.)、茅栗(C.SequiniiDode)和锥栗(C.henryiRehd.&Wils.)分布在中国大陆;日本栗(C.crenataSieb.&Zucc.)分布在日本及朝鲜半岛。分布在北美洲的有2个种:美洲栗〔C.den-tata(Marsh.)Brokh.)和美洲榛果栗(C.PumilaMill.)。美洲榛果栗曾划分为6个种:C.Pumila、C.Ozarkensis(Ashe)、C.ashei(Sidw.)、C.alnifolia(Nutt.)、C.floridena(Ahe),和C.paucispina(Ash… 相似文献
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To gain a better understanding of the effects of spatial structure on patterns of neighbourhood competition among hardwood trees, the three-dimensional extension of primary branches was surveyed for ten community-grown Castanea crenata (Fagaceae) trees with respect to the positioning of neighbouring branches and the slope of the forest floor. There were significantly more branches extending towards the lower side of the slope than towards the upper side, but structural properties such as branch length and vertical angle were not affected by slope. When horizontal extension of a branch towards its neighbour was compared for a C. crenata branch and a neighbouring heterospecific, the former was significantly narrower than the latter when the inter-branch distance (horizontal distance between the base positions of two neighbouring branches) was short (< approx. 5 m). Castanea crenata branches tended to extend in a direction avoiding neighbouring branches of heterospecifics when the inter-branch distance was short. Furthermore, for an inter-branch distance <3 m, the horizontal extension of a C. crenata branch was less when it was neighbouring a heterospecific branch than when neighbouring a conspecific branch. These results suggest that horizontal extension of C. crenata branches is more prone to spatial invasion by nearby neighbouring branches of heterospecifics, and that the invasion can be lessened when C. crenata trees are spatially aggregated. The reason why such an arrangement occurs is discussed in relation to the later leaf-flush of C. crenata compared with that of other species in the forest. 相似文献
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采用随机区组试验设计法对不同海拔高度与板栗产量的关系进行研究,通过对比分析,结果表明:不同海拔高度板栗之间的果苞数和产量差异显著,板栗产量与海拔高度未成比例关系,合适海拔高度的板栗产量高、经济效益好。适宜板栗种植的海拔高度为400~800 m。 相似文献
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Molecular evidence for an Asian origin and a unique westward migration of species in the genus Castanea via Europe to North America 总被引:1,自引:0,他引:1
The genus Castanea (Fagaceae) is widely distributed in the deciduous forests of the Northern Hemisphere. The striking similarity between the floras of eastern Asia and those of eastern North America and the difference in chestnut blight resistance among species has been of interest to botanists for a century. To infer the biogeographical history of the genus, the phylogeny of Castanea was estimated using DNA sequence data from different regions of the chloroplast genome. Sequencing results support the genus Castanea as a monophyletic group with Castanea crenata as basal. The three Chinese species form a strongly supported sister clade to the North American and European clade. A unique westward expansion of extant Castanea species is hypothesized with Castanea originating in eastern Asia, an initial diversification within Asia during the Eocene followed by intercontinental dispersion and divergence between the Chinese and the European/North American species during the middle Eocene and a split between the European and the North American species in the late Eocene. The differentiation within North America and China might have occurred in early or late Miocene. The North America species are supported as a clade with C. pumila var. ozarkensis, the Ozark chinkapin, as the basal lineage, sister to the group comprising C. pumila var. pumila, the Allegheny chinkapin, and Castanea dentata, the American chestnut. Morphological evolution of one nut per bur in the genus may have occurred independently on two continents. 相似文献
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Both qualitative and quantitative estimates of the relative amounts of several poly-phenols in buds of juvenile and adult plants of chestnut ( Castanea sativa x C. crenata ) were carried out. In buds of both types of plants, chesnatin, crenatin, cretanin and (+)-catechin were identified. Crenatin and cretanin showed inhibitory activity of peroxidase-catalysed indoleacetic acid oxidation. Auxin protection capacity was greater in extracts of the juvenile tissues which also were richer in active phenols. The phenolic content and its possible relationship to the easier establishment in vitro of juvenile tissue is discussed. 相似文献
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Kijun Nam Woo-Kyun Lee Moonil Kim Doo-Ahn Kwak Woo-Hyuk Byun Hangnan Yu Hanbin Kwak Taesung Kwon Joohan Sung Dong-Jun Chung Seung-Ho Lee 《中国科学:生命科学英文版》2015,58(7):713-723
This study analyzes change in carbon storage by applying forest growth models and final cutting age to actual and potential forest cover for six major tree species in South Korea. Using National Forest Inventory data, the growth models were developed to estimate mean diameter at breast height, tree height, and number of trees for Pinus densiflora, Pinus koraiensis, Pinus rigida, Larix kaempferi, Castanea crenata and Quercus spp. stands. We assumed that actual forest cover in a forest type map will change into potential forest covers according to the Hydrological and Thermal Analogy Groups model. When actual forest cover reaches the final cutting age, forest volume and carbon storage are estimated by changed forest cover and its growth model. Forest volume between 2010 and 2110 would increase from 126.73 to 157.33 m3 hm-2. Our results also show that forest cover, volume, and carbon storage could abruptly change by 2060. This is attributed to the fact that most forests are presumed to reach final cutting age. To avoid such dramatic change, a regeneration and yield control scheme should be prepared and implemented in a way that ensures balance in forest practice and yield. 相似文献
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Lectins belonging to the jacalin-related lectin family are distributed widely in the plant kingdom. Recently, two mannose-specific lectins having tandem repeat-type structures were discovered in Castanea crenata (angiosperm) and Cycas revoluta (gymnosperm). The occurrence of such similar molecules in taxonomically less related plants suggests their importance in the plant body. To obtain clues to understand their physiological roles, we performed detailed analysis of their sugar-binding specificity. For this purpose, we compared the dissociation constants (K(d)) of Castanea crenata agglutinin (CCA) and Cycas revoluta leaf lectin (CRLL) by using 102 pyridylaminated and 13 p-nitrophenyl oligosaccharides with a recently developed automated system for frontal affinity chromatography. As a result, we found that the basic carbohydrate-binding properties of CCA and CRLL were similar, but differed in their preference for larger N-linked glycans (e.g. Man7-9 glycans). While the affinity of CCA decreased with an increase in the number of extended alpha1-2 mannose residues, CRLL could recognize these Man7-9 glycans with much enhanced affinity. Notably, both lectins also preserved considerable affinity for mono-antennary, complex type N-linked glycans, though the specificity was much broader for CCA. The information obtained here should be helpful for understanding their functions in vivo as well as for development of useful probes for animal cells. This is the first systematic approach to elucidate the fine specificities of plant lectins by means of high-throughput, automated frontal affinity chromatography. 相似文献
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Analysis of the free amino acid pool in the chestnut fruit (Castanea sativa) shows that it is high in γ-aminobutyric acid. A metabolic connection between arginine and γ-aminobutyric acid is evident. Three enzymatic activities are involved: L-arginine ureohydrolase, L-ornithine 2-oxo-acid aminotransferase and L-glutamate carboxylyase. 相似文献
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Pérez-DE-Luque A Rubiales D Cubero JI Press MC Scholes J Yoneyama K Takeuchi Y Plakhine D Joel DM 《Annals of botany》2005,95(6):935-942
BACKGROUND AND AIMS: Orobanche species represent major constraints to crop production in many parts of the world as they reduce yield and alter root/shoot allometry. Although much is known about the histology and effect of Orobanche spp. on susceptible hosts, less is known about the basis of host resistance to these parasites. In this work, histological aspects related to the resistance of some legumes to Orobanche crenata have been investigated in order to determine which types of resistance responses are involved in the unsuccessful penetration of O. crenata. METHODS: Samples of resistance reactions against O. crenata on different genotypes of resistant legumes were collected. The samples were fixed, sectioned and stained using different procedures. Sections were observed using a transmission light microscope and by epi-fluorescence. KEY RESULTS: Lignification of endodermal and pericycle host cells seems to prevent parasite intrusion into the root vascular cylinder at early infection stages. But in other cases, established tubercles became necrotic and died. Contrary to some previous studies, it was found that darkening at the infection site in these latter cases does not correspond to death of host tissues, but to the secretion of substances that fill the apoplast in the host-parasite interface and in much of the infected host tissues. The secretions block neighbouring host vessels. This may interfere with the nutrient flux between host and parasite, and may lead to necrosis and death of the developing parasite. CONCLUSIONS: The unsuccessful penetration of O. crenata seedlings into legume roots cannot be attributed to cell death in the host. It seems to be associated with lignification of host endodermis and pericycle cells at the penetration site. The accumulation of secretions at the infection site, may lead to the activation of xylem occlusion, another defence mechanism, which may cause further necrosis of established tubercles. 相似文献