Comparative epidermal morphology of West African species of Jatropha L.(Euphorbiaceae)

Leaf epidermal morphology of the eight species of Jatropha found in West Africa has been studied by both light and scanning electron microscopy. The cells of adaxial and abaxial epidermises are usually polygonal with either straight or curved anticlinal wallS. Wax occurs in some species in the form of either flakes, particles or plugs, while in others prominent cuticular striations are found which may be parallel or random. Paracytic and brachyparacytic stomata which may be superficial, or sunken with either narrow or wide cuticular rim occur on both surfaces of the abaxial surface only. Stomatal size varies both within and between taxa. Pubescent and glabrous species occur within the genus. Trichomes are either unicellular or uniseriate. The presence of stalked glands on leaf margins is unique to J.gossypiifolia. Evidence is presented to show the close relationship between J.neriifolia and J. Atacorenis. Other variable micromorphological characters of the epidermis include cell size, periclinal walls, distribution and density of trichomes. The taxonomic significance of these features in identification and elucidation of species affinity is discussed.     

Pollen morphology in the genus Coffea (Rubiaceae) and its taxonomic significance

The pollen morphology of 38 representative species and varieties within the genus Coffea L. is described. Eight pollen types, placed in two major groups, have been identified on the basis of the number of colpi, colpus characteristics, exine morphology and pollen size. Differences in pollen structures of the species studied do not correspond to present taxonomic groupings, but support a current proposal to place some of the species in the genus Paracoffea Leroy. Among the four sections in the genus, the section Eucoffea contains a high degree of pollen polymorphism.     

The taxonomic relationships within the genus Excoecaria L. (Euphorbiaceae) based on leaf morphology and rDNA sequence data

The tropical Indo-Pacific genus Excoecaria L. (Euphorbiaceae) has several closely related species in Australia whose taxonomic relationships are unclear. The most widely reported species in Australia is the mangrove species Excoecaria agallocha L. (type species), whose taxonomic and geographic limits are difficult to define from its closely related species or sub-species. Two additional taxa have also been described but not clearly differentiated from the type species: Excoecaria dallachyana Baillon and Excoecaria ovalis Endl. This project aimed to determine the taxonomic relationships of the Australian Excoecaria species using both leaf morphological data and DNA sequence data from the internal transcribed spacer (ITS) region of ribosomal genes. The nucleotide differences in the examined ITS1 region show that E. agallocha from eastern Australia and E. ovalis from Western Australia respectively, are genetically uniform within species but differ from each other consistently, thus supporting species status. The leaf morphological data also support this view: single factor analysis of variance consistently separated E. ovalis from E. agallocha on the basis of leaf width, leaf length and length of petiole. In contrast, E. ovalis from the Gulf of Carpentaria differs only slightly from E. ovalis in Western Australia, but no evidence was found to suggest any leaf morphological differentiation within this species. The analysis also suggests that E. dallachyana is not closely related to either mangrove species E. agallocha or E. ovalis, despite superficial morphological similarities.     

Pollen morphology of Justicia L. (Acanthaceae) from Thailand and its taxonomic value

The acetolysed pollen of 33 species of the genus Justicia in Thailand is investigated using both light and scanning electron microscopy. The pollen of the genus is characterised as being isopolar, bilaterally or radially symmetrical, with mostly prolate or prolate spheroidal shape. Based on characters with high factor loading in the cluster analysis and principal components analysis, the studied species are divided into two major groups; one with 3-colporate with six pseudocolpi and the other with 2-porate or 2–3-colporate with aperture areas. The pollen morphology of each group is described and illustrated. Pollen characters are useful for taxonomic delimitation and relationships among Thai species.     

大戟科麻疯树属三种植物花器官发生

利用扫描电子显微镜观察了大戟科Euphorbiaceae麻疯树属Jatropha麻疯树J. curcas L.、佛肚树J. podagrica Hook.和棉叶麻疯树J. gossypifolia L.花器官发生。结果表明: 麻疯树、佛肚树和棉叶麻疯树花萼原基均为2/5型螺旋发生。在同一个种不同的花蕾中, 花萼的发生有两种顺序: 逆时针方向和顺时针方向。远轴面非正中位的1枚先发生。5枚花瓣原基几乎同时发生。雄花中雄蕊两轮, 外轮对瓣, 内轮对萼。研究的3种麻疯树属植物雄蕊发生方式有两种类型: 麻疯树亚属麻疯树的5枚外轮雄蕊先同时发生, 5枚内轮雄蕊后同时发生, 佛肚树亚属佛肚树和棉叶麻疯树雄蕊8-9枚, 排成两轮, 内外轮雄蕊同时发生。雌花的3枚心皮原基为同时发生。麻疯树属单性花, 雌花的子房膨大而雄蕊退化, 雄花的雄蕊正常发育, 子房缺失。根据雄蕊发生方式, 支持将麻疯树属分为麻疯树亚属subgen. Jatropha和佛肚树亚属subgen. Curcas。     

膏桐花粉活力与柱头可授性及其生殖特性研究

采用TTC法测定了膏桐花粉的活力和寿命,用联苯胺-过氧化氢法测定其柱头可授期,以套袋结果检测花粉活力与柱头可授性的变化,以研究柱头颜色变化与柱头可授性的关系以及开花式样对生殖成功的影响.结果表明:(1)膏桐雄花单花花期一般为2 d,花后0~9 h内花粉活力相对较高,24~33 h后花粉活力较低,48 h后花粉基本无活力.(2)膏桐雌花单花期为5~12 d,柱头可授性在花后1~4 d最强,5~8 d可授性开始逐渐降低,第9天基本失去可授性.(3)膏桐柱头表面无明显的渗出物,柱头的可授性与柱头颜色的变化相关,柱头绿色越多,柱头可授性越强;遇降雨时,少量雌花的花瓣展开而柱头仍呈球状,或者花瓣不展开而柱头先伸出,此时柱头可授性较差.(4)膏桐常表现为雄性先熟,尽管雌花数目较少,但开放速率较快,且集中在第3~5天开放,雌花开放完毕也仍有雄花未开放,为展开后的柱头留有较长时间等候昆虫传送花粉,为保障生殖成功提供了机会,但少数花序先开雌花,后开雄花,有支持异交而降低自交的倾向.     

小桐子花的性别与开花时间的相互关系

通过对小桐子(Jatropha curcas L.)花序上小花的开花顺序和小花性别的观察,发现其聚伞花序中心花的性别与其开花时间相关联,同时还和周围其它小花的性别有很大的相关性.中心花若在整个花序开花的第一天开放,仅有23.2%的可能是雌花;若在第二天及以后开放,有85%以上的可能为雌花.而中心花的性别又与其它花的性别相关,中心花如为雌花,那么聚伞花序上的其它小花有80%的可能性为雌花;但中心花若为雄花,那么整个聚伞花序上将不会再有雌花.研究小桐子的开花行为及性别控制规律,对于进一步人工调控小桐子花的性别表达,提高小桐子的产量、培育高产稳产品种,具有重要的应用价值.     

Comparative morphology of the leaf epidermis in the genera Codonanthe (Martius) Hanstein and Nematanthus Schrader (Gesneriaceae)*

The leaf epidermis of 14 species ofCodonanthe and 10 species of Nematanthus has been examined. Species of Codonanthe section Codonanthe are geographically restricted to south-eastern Brazil, and are diploid. They possess multicellular-uniseriate nonglandular trichomes, glandular trichomes with a four-celled head and a short body, anisocytic stomata and lack extrafloral nectaries. Species of Codonanthe section Spathuliformae and Codonanthe subgenus Codonanthella are distributed from southern Mexico through Central America to north-western South America and are tetraploid. They possess unicellular non-glandular trichomes (except C. caribaea), glandular trichomes with a two-celled head (except C. caribaea) and a short body, anisocytic stomata and extrafloral nectaries (except C. caribaea). All Nematanthus species are distributed in south-eastern Brazil and are diploid (N=8). Six species of Nematanthus consistently have multicellular-uniseriate nonglandular trichomes, glandular trichomes with a four-celled head and a short (unicellular) or long (multicellular) body, anisocytic stomata and lack extrafloral nectaries. Four species of Nematanthus have multicellular-uniseriate non-glandular trichomes, glandular trichomes with a head of more than four cells and a short body, anisocytic and helicocytic stomata and lack extrafloral nectaries.     

A taxonomic revision and pollen morphology of the genus Dendrokingstonia (Annonaceae)

The genus Dendrokingstonia (Annonaceae) is taxonomically revised and palynologically studied. Three species are recognized, one of which, D. gardneri , is described as new to science. One new combination, D. acuminata , is made. The genus occurs from southern Thailand to Peninsular Malaysia and Sumatra. On the basis of macromorphology and pollen characters, it is considered to be related to Monocarpia. Both genera show a combination of macromorphological characters that is rare in the family, i.e. considerably enlarged stigmas, leaves with percurrent tertiary veins, a highly reduced number of carpels per flower and relatively large monocarps with a thick, hard wall. Scanning and transmission electron microscopy show that the pollen grains of Dendrokingstonia and Monocarpia are monosulcate monads with a columellate infratectum and a more or less bulging intine at the sulcus. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168 , 76–90.     

Diplochory in two Jatropha (Euphorbiaceae) species of the Monte Desert of Argentina

The potential explosive seed dispersal under controlled conditions and the dispersal by ants in natural populations are compared between two diplochoric species: Jatropha hieronymi Kuntze and J. excisa Griseb. The seeds of J. hieronymi are more than eightfold heavier than J. excisa seeds, and were explosively dispersed considerably further distances, reaching a maximum of almost 18 m. The differences in explosive dispersal distances between the two species seem to depend on both carpel wall thickness of the fruit and aerodynamic shape of the seed. Seed removal by ants was positively correlated with the presence of the elaiosome and was higher for J. excisa (83.6%) than for J. hieronymi (31.6%). Seed size was the major factor affecting the removal by ants, as only large bodied ants were able to transport the large seeds of J. hieronymi. The larger size and the higher oleic acid content of the elaiosomes of J. hieronymi seeds had no influence on the observed removal rates by ants. In contrast, ants transported the J. hieronymi seeds further distances than J. excisa seeds. Jatropha hieronymi distances achieved by both dispersal modes are in the range of the furthest distances described for a diplochorous species. Finally, the possible advantages of this dispersal mode in arid zones are discussed.     

小桐子的组织培养和植株再生

以小桐子（Jatropha curcas）的胚芽、子叶、下胚轴、叶柄、叶片和茎段作为外植体,用不同浓度的6-苄基腺嘌呤（6-BA）和α-萘乙酸（NAA）对其进行愈伤组织的诱导和植株再生的研究。结果表明：在MS培养基中加入5．0mg／L6-BA和1．0mg／LNAA对愈伤组织的诱导效果最好;加入5．0mg／L6-BA和0．1mg／LNAA对不定芽的诱导最为有效,加入0．1mg／L6-BA和1．0mg／LNAA有利于芽的生长;加入1．0mg／LNAA的1／2MS培养基对生根最为有利。     

云南小桐子资源调查与评价

对云南省小桐子（Jatropha curcas）资源分布、环境因子和种子相关性状展开了调查和分析,结果表明：所测居群的种子平均千粒重、出仁率、种仁含油率和种子含油率分别为567．9克、56．67％、61．78％和35．13％。居群间种子千粒重、出仁率、种仁含油率、种子含油率都有极显著的差异,丽江A、红河D、丽江C、丽江B和玉溪A等4个居群有较高开发利用价值。温度是影响云南省小桐子地理分布的主要限制因子,分布区的海拔高度和年均温有强负相关性。云南省最适合种植小桐子的地区是金沙江和元江流域的干热河谷地区,其次是临沧、保山、普洱、西双版纳等地的高温低海拔地区。本研究对云南省小桐子的研究和产业发展提出了建议。     

小桐子EST-SSR分子标记的开发与种质遗传多样性分析

小桐子（Jatrophacurcm）适应性强,不择土壤,种子油脂性能适宜生物柴油的生产,是重要的生物柴油植物。基于小桐子种子发育过程中的EST序列,采用生物信息学方法,从4640个EST非冗余序列上鉴别了1009个SSR位点并分析其分布特征;开发了11对多态的EST—SSR分子标记,并利用这些分子标记调查了24个不同地理种源的遗传多样性,从每个位点的等位基因数目（2—3,平均为2．45）、期望杂合度（He为0．0887—0．5128,平均是0．2736）、多态信息含量（PIC为0．0847～0．4031,平均是0．2313）等方面反映了小桐子种质的遗传多样性低。进一步分析显示不同地理种源的遗传关系缺乏明显的地理结构。作者开发的EST—SSR分子标记不仅有助于小桐子种质的遗传多样性研究,也有助于小桐子种质间的遗传关系鉴别。     

中国柽柳科（Tamaricaceae）花粉形态研究及其分类意义的探讨

研究观察了中国柽柳科（Tamaricaceae)4属27种植物的花粉形态。中国柽柳科植物花粉为三沟类型,无三拟孔沟类型,形态及外壁雕纹属间差异明显。根据花粉资料,探讨了属间的进化关系和分类地位及本科植物花粉外壁的演化途径。     

Genetic Diversity of Jatropha curcas (Euphorbiaceae) Collected from Southern Yunnan,Detected by Inter-simple Sequence Repeat ( ISSR)

The genetic diversity of 158 individuals from eight semi-wild populations from Yunnan Province was estimated using ISSR method (8 primers). The results revealed an extraordinarily high level of genetic diversity ( at species level,percentage of polymorphic loci PPB = 91.04% , effective number of alleles N_e = 1.5244 , Nei′s (1973 ) gene diversity H_e= 0.3070, and Shannon′s information index H_o = 0 . 4618 ; at population level, PPB = 55. 04% , N_e = 1.3826, Nei′s (1973) gene diversity H_e = 0.2171, and Shannon′s information index H_o = 0.3178). The level of genetic differentiation between populations is lower than that among populations . The low level of genetic differentiation among populations was detected, based on Nei′s genetic diversity analysis (29.44%), and AMOVA (36.50%). There is no associations between geographical distance and genetic identity.We suggest that Jatropha curcas of Yunnan Province might not be introduced from the same place.     

Morphology and taxonomic distribution of a newly discovered feature,postero-lateral glands,in pelagic nemerteans

A variety of pelagic nemerteans from our collections off California and Hawaii between 1992 and 1997 have a pair of epidermal structures, usually visible on the intact specimens, located on the ventro-lateral margins near the caudal end of the body. The only previous reports of similar structures from pelagic or any other nemerteans are for two species of the genus Plotonemertes. Histological serial sections of at least one specimen from each of about 16 morpho-species demonstrate that these are specialized glandular regions of the epidermis, which we broadly term postero-lateral glands. The objects of this study are to describe these glands at the level of light microscopy and to consider their systematic implications and possible functions. Most of the glands consist of two more or less spatially segregated types of secretory cells. One type is usually at the anterior end of the gland and resembles typical mucous goblet cells. The other type usually is the more abundant, and resembles a nemertean serous cell, with secretion that probably is relatively proteinaceous. The glands of one of the Plotonemertes specimens have two additional types of secretory cells that are relatively abundant. This study reports on postero-lateral glands from 30 specimens: three specimens of Plotonemertes in the family Protopelagonemertidae, 18 in at least three genera of the family Pelagonemertidae, six in the monotypic family Balaenanemertidae, and three of Proarmaueria in the family Armaueriidae. The glands are relatively large, with large quantities of secretory vesicles, indicating that they must be of considerable importance to the animals. However, neither structure nor location offer self-evident clues to function of these glands. We also report on different forms of regional specialization in the epidermis of Crassonemertes and Nectonemertes, both of which lack postero-lateral glands.