焕镛木属——中国木兰科一新属

焕镛木属(Woonyoungia Law)曾分布于广西西北部罗城县,现星散分布于广西北部环江县,贵州省东部荔坡县、云南西南部马关县、是珍稀濒危树种。焕镛木属的花单性异株,与木兰科其他各属均不同;雄花的花被片形态相似而雌花的花被片则明显异形,这也是与木兰科其他各属均不同。此外,焕镛木属的雄蕊两药室稍分开,内侧向开裂,药隔伸出成舌状尖;雌蕊6-9,心皮全部合生,仅露出柱关面;成熟心皮革质,沿背缝开裂,形成近球形的聚合果。与它近缘的单性木兰属(Kmeria Dandy)则雄蕊两药室紧贴,内向开裂,顶端钝,药隔不伸出;成熟心皮木质、沿腹缝全裂及顶端开裂,最后裂成两果瓣、形成各成熟心皮散开的聚合果等不同。依上述不相同特征,故成立焕镛木属属新属。     

濒危植物焕镛木的兼性无融合生殖

2001～2002年连续两年在广西环江木论和广西罗城大黄泥的2个焕镛木(Woonyoungia septentrionalis(Dandy)Law)自然种群中,对单性异株的濒危植物焕镛木进行繁育系统测定,对即将开花的雌花花蕾分别进行套袋、套网、人工授粉处理,并用自然授粉雌花作对照,其座果率和结实率统计结果表明:自然授粉、人工授粉、套袋和套网处理的花均能结实,但它们的座果率和结实率存在较大的差异.在两个种群中,人工授粉和自然授粉的总结实率(PERS)均比套袋和套网处理的高,其中人工授粉的最高,套网处理的最低.由此可见,焕镛木既能通过有性生殖方式结实,又能通过无融合生殖方式结实,而且这两种生殖方式获得的种子均能萌发成幼苗,由此断定,焕镛木的繁育系统为兼性无融合生殖.这是首次报道木兰科植物存在无融合生殖现象.     

濒危植物焕镛木的兼性无融合生殖

2001—2002年连续两年在广西环江木论和广西罗城大黄泥的2个焕镛木(Woonyoungia septentrionalis (Dandy) Law)自然种群中,对单性异株的濒危植物焕镛木进行繁育系统测定,对即将开花的雌花花蕾分别进行套袋、套网、人工授粉处理,并用自然授粉雌花作对照,其座果率和结实率统计结果表明：自然授粉、人工授粉、套袋和套网处理的花均能结实,但它们的座果率和结实率存在较大的差异。在两个种群中,人工授粉和自然授粉的总结实率(PERS)均比套袋和套网处理的高,其中人工授粉的最高,套网处理的最低。由此可见,焕镛木既能通过有性生殖方式结实,又能通过无融合生殖方式结实,而且这两种生殖方式获得的种子均能萌发成幼苗,由此断定,焕镛木的繁育系统为兼性无融合生殖。这是首次报道木兰科植物存在无融合生殖现象。     

焕镛木小孢子发生及雄配子体发育研究

运用常规石蜡切片法和细胞学压片法,对焕镛木[Woonyoungia septentrionalis (Dandy) Law]小孢子发生、雄配子体发育以及花粉萌发进行观察分析.结果显示:焕镛木花单性,雄花的雄蕊多数、离生,每一花药具4个花粉囊,花药壁5～7层.腺质绒毡层具1～2层细胞;小孢子形成时胞质分裂方式为修饰性同时型;四分体排列方式以四面体型为主,并有交叉型和左右对称型,偶见T型和直线型;成熟花粉粒为二细胞型花粉粒.小孢子发生和雄配子体发育过程中存在变形及败育现象.花粉萌发率为79.89%～80.62%.结合焕镛木花粉粒数目和萌发率的分析认为,雄配子体发育中的败育不是影响焕镛木濒危的主要因素.     

基部被子植物雪香兰（金粟兰科）单性花的形态发生和发育

基部被子植物金粟兰科（Chloranthaceae）的单性花或两性花结构十分简单,雪香兰（Hedyosmum orientale）花单性、雌雄异株,花的形态及结构与其它属物种具有显著的差异,对于研究被子植物花特别是花被的起源和系统进化具有重要意义。该研究采用电子显微镜和光学显微镜观察了雪香兰单性花的器官发生及发育过程。结果表明,雌、雄花均为顶生和腋生,多个小花呈聚伞圆锥状排列。雄花外侧是苞片,每朵雄花上着生150–200个雄蕊,花轴基部着生少数退化的叶原体。苞片原基及其腋生的花原基最初呈圆丘状,随后伸长。在雄花发育过程中,苞片原基比雄蕊原基生长快,雄花原基纵向伸长,叶原体原基在基部发生,雄蕊原基自下而上发生。每2朵雌花底部合生形成小聚伞花序,每朵雌花被一苞叶包裹,由单心皮和三棱型子房构成,外覆三裂叶状花被。在雌花发育过程中,雌花原基比苞片原基生长快,花被原基首先于花顶端发生,随后花顶端中心凹陷,进一步发育成具有单心皮的子房原基。雪香兰的单性花发育不经过两性同体阶段,花分生组织只起始雄蕊器官或雌蕊器官的发育。研究结果支持雪香兰单性花是原始性状的观点,雄花叶原体与雌花三裂叶状花被同源,可能是花被（萼片与花瓣）的起源。     

单性木兰花部综合特征及其传粉适应性

对单性木兰花部综合特征和访花昆虫种类及访花行为进行了研究,结果表明,单性木兰花冠顶端呈半合拢状,花被片之间存在间隙,只有那些能够穿过这些间隙的昆虫才能到达花内为其采粉和授粉,对访花者的要求较为苛刻。于降雨前去掉雄花和雌花花被片,使雄花雄蕊群和雌花柱头充分暴露,另外选择雄花和雌花作对照,降雨后将花取回并测定雄花花粉生活力和雌花柱头上的花粉粒。结果表明,在雨天,单性木兰花冠顶端呈半合拢状的开放方式对雄花和雌花均起到了保护作用,这种花部结构的特化是对花期持续降雨的一种生态适应。从访花昆虫种类上看,单性木兰雄花的昆虫种类是雌花的两倍,显然雄花比雌花更能吸引昆虫。     

极危植物焕镛木的群落学特征及其保护

对广西罗城大黄泥常绿阔叶林进行样方调查,分析了极危植物焕镛木(Woonyoungia septentrionalis (Dandy)taw)群落的组成结构特征.1200 m2样地内有维管植物129种,隶属57科103属,以热带属占绝对优势;优势科为樟科、壳斗科、茜草科等.群落中焕镛木为优势种,重要值最大,为35.06,其次为粗丝木、红锥,重要值分别为22.09和19.66,因此,本群落可命名为焕镛木-粗丝木-红锥群落(Woonyoungia septentrionalis+Gomphandra tetrandra+Castanopsis hickelii Community).群落成层现象明显,可分为乔木层(3亚层)、灌木层和草本层3个层次,层间植物丰富.生活型以中、小高位芽为主,占67.18%.叶型以中、小型革质单叶为主.种群频度分布规律为A>B>CE,属于A级的种类占优势,为总种数的41.09%.乔木径级以小径级为主.焕镛木是我国南亚热带常绿阔叶林中非常珍稀濒危的物种,希望有关部门尽快在此设立保护区,以保护焕镛木的种质基因资源.     

番荔枝科两种植物花器官形态发生

用扫描电镜观察了囊瓣木（Saccopetalum prolificum）和刺果番荔枝（Annona muricata）花器官的形态发生过程。刺果番荔枝和囊瓣木花被片均为3轮,其中刺果番荔枝内轮花被片数目为3枚、5枚或7枚。囊瓣木花原基最初为圆锥形,最外轮3枚花被片很快发生,之后中、内轮花被片原基连续发生,3轮花被片互生。此时花原基为六边形。花被片分化完成时,圆球形雄蕊原基沿六边形花原基的6个边螺旋向心发生,最终近轮状排列于花原基上。刺果番荔枝的雄蕊较多（约1000枚）,首先在中轮花被片所对的花原基边缘发生,之后大量雄蕊螺旋状发生。心皮分化的早期阶段,与雄蕊原基很相似,当心皮数目逐渐增多时,不能分辩出发生的顺序。成熟花中,心皮和雄蕊全都被毛覆盖,毛具有粘住传粉滴的作用。     

华北驼绒藜开花生物学特性研究

对华北驼绒藜的开花生物学特性进行了具体调查统计研究.结果显示,华北驼绒藜种群形成了一系列适应风媒传粉的花部特征:单性花,雌雄同株;雄花序细长而柔软,雄蕊4枚,无苞片;雌花小,无花冠,柱头指状,具有大量乳突细胞,便于捕捉花粉;居群内同一植株雌、雄花花期不一致性较高,花期不遇;每枝条雄花开花持续时间频率最高为7 d,而雌花开花持续时间频率最高为6 d;雌、雄花序呈单峰连续集中开花式样;雌、雄花始花时间与花期长度均呈极显著负相关(雌花r=-0.569,P＜0.01;雄花r=-0.665,P＜0.01),开花数与花期长度则为显著正相关关系(r=0.083,P＜0.01),(r=0.346,P＜0.01).研究表明,华北驼绒藜在长期的进化过程中,形成了同株雌、雄花花期不遇的生殖策略,因而减少了同株授粉的比例,提高了结实率.     

中国桑科资料(二)

<正> 本种与尖叶榕(F. henryi Warb.)相似,但叶多变异,长披针形或为琴形,全缘或两侧裂片状,背面被极少白色糖毛,榕果近球形或圆锥状,表面散生白色糙毛,榕果体下部收缢;总花梗长约5毫米,雄花长约2毫米,花被片4,倒卵形,雄蕊2—3枚,雌花长5毫米,有梗,花被片4,倒披针形,子房具柄,花柱侧生,柱头漏斗形;瘿花与雌花相似,但     

单性木兰属(木兰科)植物的分类学订正

根据对单性木兰属Kmeria(Pierre)Dandy植物标本的研究和野外调查,补充描述了该属的一些形态特征,纠正了前人对该属描述中的一些错误,阐述了保留单性木兰属的理由,列出了分种检索表,将焕镛木属Woon-youngiaLaw和单性木兰组MagnoliaLinn.sect.Kmeria(Pierre)Figlar&Noot.作为单性木兰属的新异名,将焕镛木Woonyoungiaseptentrionalis(Dandy)Law和广西木兰MagnoliakwangsiensisFiglar&Noot.作为单性木兰KmeriaseptentrionalisDandy的新异名。     

Phyllotaxis of vegetative shoots, lamina rotation and their systematic implication in Magnoliaceae

Phyllotaxis in vegetative shoots and lamina rotation of Magnoliaceae are described. Most genera in Magnoliaceae investigated (except Parakmeria , Manglietiastrum and Pachylarnax ) show lamina rotation. Paraphoric, a new type of lamina rotation differing from four other types depicted by Charlton is clarified. Manglietia , Parakmeria , Manglietiastrum , Talauma , section Gwillimia and Rytidospermum in subgenus Magnolia , shoots of Woonyoungia , section Theorhodon and Liriodendron have spiral phyllotaxis, however Magnolia section Oyama and Maingol a, Alcimandra , Michelia , Paramichelia , Tsoogiodendron , buds of Woonyoungia , section Theorhodon and Liriodendron have distichous phyllotaxis. The systematic implication of vegetative shoot phyllotaxis and lamina rotation in Magnoliaceae is discussed in this paper.     

濒危植物单性木兰种群径级结构和生命表分析

单性木兰是我国特有的濒危植物。对广西北部木论自然保护区内的单性木兰代表种群进行调查,分析其种群径级结构和存活曲线,编制了静态生命表。结果表明:雄株与雌株的比例约1.06:1,幼苗和幼树在种群中占有较大的比重,单性木兰种群的径级结构呈非典型的金字塔型分布,为稳定型种群;存活曲线接近Deevey-Ⅲ型,种群在两个低龄级Ⅰ和Ⅲ出现相对较高的死亡高峰,死亡率分别为0.23和0.35,而高径级趋于稳定。     

Anatomy and ontogeny of unisexual flowers in dioecious Woonyoungia septentrionalis （Dandy） Law （Magnoliaceae）

Woonyoungia septentrionalis （Dandy） Law is aceae. The floral morphology and structure of the species a dioecious species with unisexual flowers in Magnoliare conspicuously different from other species and are important to the study of floral phylogeny in this family. The floral anatomy and ontogeny were investigated to evaluate the systematic position of W. septentrionalis, using scanning electron microscopy and light microscopy. All of the floral organs are initiated acropetally and spirally. The carpels are of conduplicated type without the differentiation of stigma and style. The degenerated stamens in the female flowers have the same structures as the normal stamens at the earlier developmental stages, but they do not undergo successive development and eventually degenerate. The male floral apex was observed to have the remnants of carpels in a few investigated samples. As the bisexual flower features could be traced both in the male and female flowers in W. septentrionalis, it suggests that the flower sex in Magnoliaceae tends toward unisexual. As well as the unisexual flowers, the reduced tepals and carpels and concrescence of carpels conform to the specialized tendency in Magnoliaceae, which confirms the derived position of W. septentrionalis in this family. As the initiation pattern of floral parts of W. septentrionalis is very similar to other species in this family, it needs further investigation and especially comparison with species in Kmeria to evaluate the separation of Woonyoungia.     

Fatty acid profiles of brain phospholipid subclasses of rats fed n - 3 polyunsaturated fatty acids of marine or vegetable origin. A two generation study.

The effects of dietary n - 3 polyunsaturated fatty acids (PUFA) on fatty acid profiles of rat brain phospholipid subclasses as well as on heart phosphatidylethanolamine through two generations were examined: Three groups of rats were fed 20 weight% fat diets in which approx. 30% of the fatty acids were polyunsaturated, either 17% linoleic acid + 13% C20(-) + C22 polyunsaturates from fish oil or 17% linoleic + 13% alpha-linolenic acid from linseed oil or 30% linoleic acid. The rats of the two generations were killed as adults at 18 weeks of age. The results demonstrated that fish oil was a better source than alpha-linolenic acid for incorporation of n - 3 PUFA into the examined phospholipids. This was seen both in brain and heart tissue and in both generations of rats. In the brain phosphatidylethanolamine (PE) and phosphatidylserine (PS) similar fatty acid profiles were found in 1st and 2nd generation, but fish oil was more efficient than 18:3(n - 3) in increasing the levels of 22:6(n - 3), 20:5(n - 3), 22:5(n - 3) and reducing 20:4(n - 6) and 22:5(n - 6). Fatty acid profiles of phosphatidylinositol (PI), phosphatidylinositol-4-phosphate (PIP) and phosphatidylinositol-4,5-bisphosphate (PIP2) were affected by dietary fats. In PIP and PIP2 of 2nd generation rats 20:4(n - 6) was reduced from 36 to 29% following fish oil intake, whereas alpha-linolenic acid had no effects. The cholesterol/phospholipid ratio was not affected in the brain, neither was the degree of unsaturation of the phospholipids. In heart PE the highest levels of 20:5(n - 3)(2%) and 22:6(n - 3) (36%) were observed following fish oil intake. However, in rats fed alpha-linolenic acid a considerable increase in the level of 22:6(n - 3) was observed from the 1st (21%) to the 2nd generation (26%).     

Flow cytometric detection of circulating dendritic cells in healthy subjects

Dendritic cells (DCs) are the key antigen-presenting cells controlling the initiation of the T cell- dependent immune response. Currently, two peripheral blood DC subsets have been identified on the basis of their CD11c expression. The CD11c-negative (CD11c-) DCs (expressing high levels of CD123) are designated as lymphoid-derived DCs (DC2), whereas the CD11c+/CD123- cells, do identify the myeloid-derived DCs (DC1). A growing number of studies have been conducted in recent years on both the quantitative and functional alterations of DCs and their subsets in different pathological conditions. In the present study we assessed, using two different flow cytometric (FCM) techniques, the normal profile of blood DCs in 50 italian adult healthy subjects (M/F: 25/25, median age 42.5 years, range 20-65). The percentage and the absolute number of DCs and their subsets, were obtained starting from whole blood samples in two ways: 1) by calculating the number of DCs when gated as lineage-negative/ HLA-DR+ and identifing the two subsets as CD11c+ (DC1) and CD123+ (DC2) and 2) by using three specific markers: BDCA.1 (CD11c+ high/CD123+ low, myeloid DCs); BDCA.2 (CD11c-/ CD123+high, lymphoid DCs); BDCA.3 (CD11c+low /CD123-, myeloid DCs). Six parameters, 4-color FCM analysis were perfomed with a BD FACSCanto equipment. The mean values of the percentage and of the absolute number were: 0.5+/-0.2% and 30+/-11 cells/microL for DCs; 0.2+/-0.1% and 15+/-6 cells/microL for DC1; 0.2+/-0.1% and 15+/-7 cells/microL for DC2. The same values were: 0.2+/-0.1% and 16+/-7 cells/microL for BDCA.1; 0.2+/-0.1% and 12+/-7 cells/microL for BDCA.2; 0.02+/-0.01% and 2+/-1 cells/microL for BDCA.3, respectively. Our study confirmes that the two types of FCM analysis are able to identify the DC population. We also provides the first reference values on normal rates and counts of blood DCs in italian adult healthy subjects.     

Structure determination of oligosaccharides isolated from Cad erythrocyte membranes by permethylation analysis and 500-MHz 1H-NMR spectroscopy

Alkaline borohydride reductive cleavage (beta-elimination) of glycophorin A isolated from one individual of the rare blood group Cad, resulted in the release of six acidic oligosaccharide-alditols which were separated by high-performance liquid chromatography (HPLC) on an alkyl amine silicagel column. The structure of four of them has been determined by the application of methanolysis, methylation analysis and 1H-NMR spectroscopy at 500 MHz. The structures and relative amounts were as follows: oligosaccharide 1: NeuAc(alpha 2-3)Gal(beta 1-3)GalNAc-ol (3.5%); oligosaccharide 3: GalNAc(beta 1-4)[NeuAc(alpha 2-3)]Gal(beta 1-3)GalNAc-ol (10.5%); oligosaccharide 5: NeuAc(alpha 2-3)Gal(beta 1-3)[NeuAc(alpha 2-6)]GalNAc-ol (10.4%); oligosaccharide 6: GalNAc(beta 1-4)[NeuAc(alpha 2-3)]Gal(beta 1-3)[NeuAc(alpha 2-6)]GalNAc-ol (71.2%). The two other oligosaccharides (2 and 4) were obtained in very low amount. The major pentasaccharide (oligosaccharide 6) carries the blood group Cad determinant and is a potent inhibitor of human anti-Sda antibody.