The Induction of Contractile Root Activity in Sauromatum guttatum (Araceae)

Contraction of Sauromatum guttatum roots creates a slow, downward underground corm movement, the corm be-coming covered by a greater amount of soil, and the geophilous plant surviving the dormancy period at a safer soil position. Corm movement of Sauromatum guttatum is only possible if root contraction results in pulling activity. This pulling activity can be quantified using the lifting technique. Measurements of the pulling activity are shown as working curves over time and as the maximum work of a single contractile root. Our results show that root activity varies in individuals cultivated under different parameter conditions. It can be shown that two factors induce root contraction: first, rapid temperature fluctuations during the preceding growth period; second, illumination of the sheath leaves during the actual growth period. However, light induction is, as found here, more important and hierarchically superior, for the temperature effect is only seen in plants whose sheath leaves are not illuminated. Mobility of S. guttatum plants can thus be described as photo-movement. If the light effect is not present, the mobility of S. guttatum may become thermo-movement. However, at present, there is no indication that this movement is oriented to the direction of stimulus.     

斑龙芋属(天南星科)及近缘属植物的叶表皮形态

光镜、电镜下观察了天南星科天南星族下斑龙芋属2个种及近缘属13个种植物的叶表皮形态特征。实验结果显示,4属植物的叶表皮组成及其形态特征较相似,属间不存在明显差异,但某些特征在种间存在差异,可作为种的鉴别特征。叶表皮特征支持将单籽犁头尖和昆明犁头尖两个种合并为一个种。15个种的气孔器均具有2个副卫细胞,Stebbins andKhush认为这是气孔器类型中较具2个以上副卫细胞更进化的一种类型,而天南星科大多数族的气孔器都具有2个以上的副卫细胞,这也证明了天南星族是天南星科较进化的族。     

Ultrastructural changes in the appendix of the Sauromatum guttatum inflorescence during anthesis

Summary The ultrastructure of the epidermal and sub-epidermal cells of the appendix of the Sauromatum guttatum inflorescence reveals developmental changes during anthesis. These changes precede, and probably make possible, heat and odor production. Two days before D-day (the day of heat production and inflorescence-opening) the mitochondria of the epidermis divide; apparent division of the amyloplasts was observed at the same time. The presence of lipid bodies and peroxisomes in the epidermis was clearly evident. On D-day, the epidermis becomes a continuous layer in which the cell walls separating two adjacent cells disappear. At the same time, in the sub-epidermal cells, the mitochondria and the amyloplasts undergo division. The mitochondria become electron-dense, and their DNA is clearly visible. On that day, lipids as well as starch are being depleted. The peroxisomes change in structure every day, from D-2 to D-day. It has also been demonstrated by histochemical techniques that during anthesis the activity of cytochrome c oxidase (3,3-diaminobenzidine as a substrate) decreases whereas the activity of NADH dehydrogenase [tetrazolium salts: nitro-blue tetrazolium chloride (NBT) or neotetrazolium chloride (NT) in the presence of NADH], increases. Oxygen consumption of isolated mitochondria from the D-day appendix was inhibited in the presence of the two tetrazolium salts to a different degree: oxidation of NADH in the presence of NBT was the most sensitive to inhibition, more so than the oxidation of malate and succinate. NT was less effective as an inhibitor in the presence of those three respiratory substrates.     

Purification and partial characterization of two biologically active compounds from the inflorescence of Sauromatum guttatum Schott (Araceae)

The active principle triggering the metabolic outburst of theappendices of certain arum lily species has been purified andpartially characterized. Although in the past it has been thoughtof as a single factor ("calorigen"), both paper chromatographyand DEAE-Sephadex ion exchange chromatography reveal that thereare two compounds (calorigen I and II) with calorigen activity.These can act alone or together, but show no synergism. Theyare low-molecular compounds which appear to be common constituentsof the inflorescence of Sauromatum guttatum Schott. CalorigenII is also present in the spadix of Arum maculatum L., Arumdioscoridis Sibth. & Sm., and Dracunculus vulgaris Schott.Calorigen I absorbs UV at 242, 267 and 278 nm, calorigen IIat 229 and 295 nm. No spectral changes are noted in alkalineenvironment, whereas at low pH-values there is a shift of theabsorption peaks of both compounds towards longer wavelengths.Calorigen II displays a strong blue fluorescence and has a maximalemission at 410 nm when activated at 295 nm. The possible mechanismof calorigen action is discussed. ¹ Present address: Department of Biochemistry, University ofWashington, Seattle, Washington 98195, U.S.A. (Received August 26, 1974; )     

中国天南星科花粉形态的研究

利用扫描电镜对天南星科Araceae22属28种(除Arum maculatum产自德国外,其余均产自中国) 及菖蒲科Acoraceae 1属2种植物的花粉形态进行了观察。结果显示天南星科花粉形态在科内变异很 大。花粉粒形状从球形、近球形、椭球形到扁球形和橄榄形;萌发孔类型有散孔型、具薄壁区型、环沟型 或无萌发孔;外壁纹饰为小穴状、网状、肋条状、条纹状、疣状、具刺或光滑。主要依据花粉形态方面的证 据探讨了崖角藤属Rhaphidophora、麒麟叶属Epipremnam 、龟背竹属Monstera 3属的属间关系以及犁头尖属Typhonium属下分类中存在的一些问题。     

Flavonoids and xanthones from the leaves of Amorphophallus titanum (Araceae)

The flavonoids and xanthones in the leaves of Amorphophallus titanum, which has the largest inflorescence among all Araceous species, were surveyed. Eight C-glycosylflavones, five flavonols, one flavone O-glycoside and two xanthones were isolated and characterized as vitexin, isovitexin, orientin, isoorientin, schaftoside, isoschaftoside, vicenin-2 and lucenin-2 (C-glycosylflavones), kaempferol 3-O-robinobioside, 3-O-rutinoside and 3-O-rhamnosylarabinoside, and quercetin 3-O-robinobioside and 3-O-rutinoside (flavonols), luteolin 7-O-glucoside (flavone), and mangiferin and isomangiferin (xanthones). Although the inflorescence of this species has been surveyed for flavonoids, those of the leaves were reported for the first time.     

花叶芋(天南星科)的花器官发生

利用扫描电镜首次观察了天南星科花叶芋(Colocasia bicolor) 的花器官发生过程。花叶芋的肉穗花序由无花被的单性花构成, 雌花发生于花序基部, 雄花发生于花序上部, 中性花位于花序中间部位。雄花: 3 或4 个初生雄蕊原基轮状发生, 随后每个初生原基一分为二, 形成6或8个次生原基; 一部分次生原基在其后的发育过程中融合, 形成5 或7 枚雄蕊; 雄花发育过程中未见雌性结构的分化; 花药的分化先于花丝; 雄蕊合生成雄蕊柱。雌花: 合生心皮, 3或4个心皮原基轮状发生, 未见雄性结构的分化。中性花来源于雌雄花序过渡带上, 属于雄蕊原基的滞后发育以及发育成熟过程中的退化; 与彩叶芋属(Caladium)不同, 此过渡区未见畸形两性花。初生雄蕊原基二裂产生次生原基的次生现象在目前天南星科花器官发生中显得比较特殊, 同时初步探讨了次生原基的融合方式。     

国产芋属花粉形态

通过光镜和扫描电子显微镜观察了芋属(Colocasia Schott)6种、1变种、1品种的花粉形态,其中贡山芋C．gaoligongensis,龚氏芋C．gongii,李氏香芋C．lihengiae,花叶芋C．bic-olor4个种为首次报道。本属花粉为圆球形,无萌发孔。外壁纹饰分为两类：大野芋C．giga-ntea外壁光滑无刺,其余各种均具刺。花粉大小为20．07—32．76μm。     

天南星科斑龙芋属植物的核型研究

报道了天南星科（Araceae)斑龙芋属（Sauromatum)两种植物的型,它们的静止核均为渐变型,分裂前期染色体均为中间型,体细胞中期染色体均为2n=26,核型分别为：斑龙芋（S.venosum)2n=2x=26=14m 12sm;高黎贡山斑龙芋（S.gaoligongense)2n=2x=26=10m 12sm 4st,其中高黎南山斑龙芋的染色体数目和核型为首次报道。本文还就斑龙芋属的分类地位进行了初步讨论,认为在尚未进行更详细的、多方面的综合研究之前,仅从一些形态上的相似性就匆忙将斑龙芋属归并到犁头尖属是值得商榷的,并从珠芽和细胞学两方面的特性推断属与半夏属可能有较近的亲缘关系。     

Araceae of Mulu National Park. I. Four new species of Schismatoglottis (Araceae)

Four new species of Schismatoglottis are described and illustrated from Mulu National Park in Malaysian Borneo: Schismatoglottis fossae (Patentinervia Clade), S. roseopedes and S. serratodentata (Calyptrata Clade) and S. pellucida (currently unplaced but likely in the Multinervia clade). A brief summary is provided of botanical exploration at Mulu, notably where pertinent to aroid botany.     

Improvements for Observing Anthurium (Araceae) Floral Structures by Light Microscopy

Three major obstacles must be overcome In the anatomical study of Anthurium floral structure and embryo development including presence of mucilage, hardened carpel walls, and hardened seed coat in the developing fruit and seed. Fixation in 6% glutaraldehyde and 1% cetylpyridinium chloride in 0.05 M sodium cacodylate, pH 6.8, effectively fixed or removed mucilage from the locules of Anthurium andraeanum Hort. in spadices. This treatment enhanced infiltration of the embedding medium through the hardened carpel wall into the locule space and decreased the quantity and size of holes in the embedding block during sectioning. Specimens 16 weeks after pollination could be fixed, infiltrated, and observed without physical removal of the seed coat. Embryos may be excised from the seed at later stages without compromising embryo structure.     

Identification and characterization of 43 novel polymorphic EST-SSR markers for arum lily,Zantedeschia aethiopica (Araceae)

• Premise of the study: A new set of microsatellite or simple sequence repeat (SSR) markers from expressed sequence tags (ESTs) was developed for arum lily (Zantedeschia aethiopica), which is one of the most iconic and widely recognized ornamental plants in the world. • Methods and Results: Using 2175 unigenes derived from 4283 random ESTs in arum lily, 166 primer pairs were designed and tested for amplification in 24 accessions from Asia, Europe, and Africa. A total of 43 loci were polymorphic, with the number of alleles per locus ranging from two to 10. The observed heterozygosity, expected heterozygosity, and polymorphism information content ranged from 0.2313 to 0.8480, 0.3034 to 0.8648, and 0.1015 to 0.7364, respectively. • Conclusions: These novel polymorphic EST-SSR markers will facilitate future studies of genetic variation and molecular-assisted breeding systems in arum lily.     

Oxidation of Proline and Glutamate by Mitochondria of the Inflorescence of Voodoo Lily (Sauromatum guttatum)

In appendices of Sauromatum guttatum that are developing thermogenicity, mitochondria isolated from successive developmental stages of the inflorescence show an increase in the oxidation rates of proline and glutamate. A similar rise in the oxidation rates of these compounds is observed in mitochondria obtained from the spathe, a nonthermogenic organ of the inflorescence. Changes in oxidative metabolism were also observed in mitochondria isolated from sections of immature appendix treated with salicylic acid (SA) at 0.69 microgram per gram fresh weight indicating that they are induced by SA. At that concentration, however, SA has no effect on oxygen consumption by mitochondria in the presence of glutamate, proline, or malate. Furthermore, oxygen uptake by mitochondria in the presence of proline or glutamate is partially sensitive to salicylhydroxamic acid (SHAM) at concentrations greater than 2 millimolar when in the presence of 1 millimolar KCN. For NADH, succinate, and malate a high capacity of the alternative (cyanide-resistant) pathway is found that is completely sensitive to SHAM at 1.5 to 4 millimolar. The increase in the mitochondrial capacity to oxidize either amino acid is also found in four other Araceae species including both thermogenic and nonthermogenic ones. After anthesis, the rates of proline and glutamate oxidation decline.     

Reasons and consequences of the lack of a sporopollenin ektexine in Aroideae (Araceae)

The ultrastructure of pollen walls in Araceae is characterized by the absence of a stable sporopollenin outer exine layer in subfamily Aroideae, and by the presence of several distinctive pollen characters typical for the other aroid subfamilies. This article discusses if and to which extent such distinctive pollen characters are mirrored in various classifications of Araceae, basing either on morphological or on molecular data. Accordingly, the pollen characters perfectly reflect the actual subfamily classification, and also recent arrangements of clades in trees basing on molecular data. The actual subfamilies appear no longer eurypalynous, but now strictly stenopalynous. Aside from the (settled) classification problem the fundamental question is addressed why do Aroideae lack an elaborated sporopollenin ektexine. Possible pollination biology benefits, deriving from an absence of an elaborated sporopollenin ektexine in Aroideae, are presented and discussed. Compared with all other subfamilies the most advanced and by far largest subfamily Aroideae has lost several crucial characters and simultaneously acquired corresponding opposed characters, amongst others a non-sporopollenin exine layer and an unusual thick and spongy endexine. Taken together, losses and acquisitions are interpreted as a major paradigm shift in Araceae evolution, which took place according to the fossil record probably in the Paleogene.     

Purification of a NAD(P) Reductase-Like Protein from the Thermogenic Appendix of the Sauromatum guttatum Inflorescence

A NAD(P) reductase-like protein with a molecular mass of 34.146 ± 34 Da was purified to homogeneity from the appendix of the inflorescence of the Sauromatum guttatum. On-line liquid chromatography/electrospray ionization-mass spectrometry was used to isolate and quantify the protein. For the identification of the protein, liquid chromatography/electrospray ionization-tandem mass spectrometry analysis of tryptic digests of the protein was carried out. The acquired mass spectra were used for database searching, which led to the identification of a single tryptic peptide. The 12 amino acid tryptic peptide (FLPSEFGNDVDR) was found to be identical to amino acid residues at the positions 108–120 of isoflavone reductase in the Arabidopsis genome. A BLAST search identified this sequence region as unique and specific to a class of NAD(P)-dependent reductases involved in phenylpropanoid biosynthesis. Edman degradation revealed that the protein was N-terminally blocked. The amount of the protein (termed RL, NAD(P) reductase-like protein) increased 60-fold from D-4 (4 days before inflorescence-opening, designated as D-day) to D-Day, and declined the following day, when heat-production ceased. When salicylic acid, the endogenous trigger of heat-production in the Sauromatum appendix, was applied to premature appendices, a fivefold decrease in the amount of RL was detected in the treated section relative to the non-treated section. About 40 % of RL was found in the cytoplasm. Another 30 % was detected in Percoll-purified mitochondria and the rest, about 30 % was associated with a low speed centrifugation pellet due to nuclei and amyloplast localization. RL was also found in other thermogenic plants and detected in Arabidopsis leaves. The function of RL in thermogenic and non-thermogenic plants requires further investigation.     

Club‐Shaped Organs as Additional Osmophores within the Sauromatum Inflorescence: Odour Analysis,Ultrastructural Changes and Pollination Aspects4

Abstract: Gradient odour emissions in the inflorescence of the Araceae Sauromatum guttatum aim to attract a wide range of insects into the floral chamber. The volatiles are emitted from the spadix appendix, as well as the club‐shaped organs located directly above the female flowers. Volatile analysis of various regions of the appendix and the club‐shaped organs led to the identification of 163 compounds emitted by the appendix top, 124 by the appendix bottom and 105 by the club‐shaped organs. The dominant compounds in all investigated tissues were monoterpenes and sesquiterpenes that were accompanied by numerous aliphatic, aromatic, sulphur‐ and nitrogen‐containing compounds of other biosynthetic origins. Within the appendix, levels of one monoterpene, β‐citronellene, showed considerable variation; it constituted the major compound in the appendix top and gradually decreased in the lower regions, being undetectable in the base. The other prominent monoterpenes, α‐pinene, β‐pinene, limonene, α‐phellandrene and β‐phellandrene, showed no changes along the appendix. The club‐shaped organs located at the base of the floral chamber also emitted volatiles, though of different composition: the monoterpenes α‐terpinolene and linalool constituted major amounts, instead of β‐pinene and β‐citronellene. These qualitative differences and the absence of methanethiol in the club‐shaped organs result in them having a pleasant flowery odour, in contrast to the foul‐smelling appendix. The quantitative spatial variation of β‐citronellene within the appendix and the existence of a second osmophore within the floral chamber, emitting a different scent, suggest that both phenomena might participate in creating an odour gradient for efficient pollinator attraction. Apart from β‐citronellene, nearly all major components of the appendix have already been identified as specific attractants to a broad range of insects that have been observed to be lured to the odour‐emitting inflorescence. Most likely, the club‐shaped organ odour serves to induce the insects attracted by the appendix to move towards the floral chamber. A comparison of the relative emission rates demonstrated that performance of the club‐shaped organs equals or even exceeds the appendix. In the club‐shaped organ tissues, multivesicular bodies, originating from lipid droplets, are the most notable organelles before and during odour production. They fuse with the plasma membrane, releasing their content to the exterior of the cell. The exit route for the volatiles is an extensive intercellular channel system that extends to the surface of the club‐shaped organs. Thus, chemical and ultrastructural analyses suggest, in contrast to previous studies, that the club‐shaped organs function as an osmophore rather than a food source for insects.     

Ariopsis macrosperma sp. nov. (Araceae) from the northern Western Ghats,India

Ariopsis macrosperma sp. nov. from Western Ghats of Maharashtra, India, is described and illustrated. It differs from the other two species in the genus, A. peltata and A. protanthera, in having a typical terrestrial habit, growing on the soil as undergrowth below the forest canopy, thick, leathery leaves and lower number of larger, ovoid and ribbed seeds.     

Chemical constituents from the tubers of Pinellia ternata (Araceae) and their chemotaxonomic interest

This work describes the isolation and characterization of twenty compounds from the tubers of Pinellia ternata (Thunb.) Breit, including 17 lignanoids (1–17) and three alkaloids (18–20). All structures were established based on analysis of their spectroscopic data. It is the first report of compounds 3–11 and 13–18 from the genus Pinellia, and the first report of compounds 3–4, 6–9, 11 and 13–18 from the family Araceae. In addition, the biosynthetic pathways of the 17 lignanoids are summarized. A liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOFMS/MS) method in both positive and negative ion mode was also used to confirm the identity of these seventeen lignanoids from the tubers of P. ternata. The results from the present work provide further information about the diversity of compounds in the genus Pinellia.     

New insights into the phylogeny and biogeography of subfamily Orontioideae (Araceae)

Proto‐Araceae, the earliest diverged lineage within the family Araceae, includes two subfamilies, Gymnostachydoideae (one species) and Orontioideae (eight species). Based on an extensive sampling (a total of 198 accessions) of six chloroplast non‐coding regions (5799 aligned sites), we assessed phylogenetic relationships among the genera and species within subfamily Orontioideae and estimated the timing of intercontinental disjunct events in the Northern Hemisphere. Overall phylogenetic relationships among the genera were consistent with results from previous studies, but several new important findings were discovered, primarily within Symplocarpus Salisb. ex W. P. C. Barton. First, two major lineages within Symplocarpus were identified: one lineage included S. foetidus (L.) Salisb. ex W. Barton, S. nabekuraensis Otsuka & K. Inoue, and S. renifolius Schott ex Tzvelev (Japan), whereas the other included S. nipponicus Makino, S. egorovii N. S. Pavlova & V. A. Nechaev, and S. renifolius (Korea). Symplocarpus renifolius in Japan was tetraploid and closely related to the tetraploid S. foetidus in eastern North America. Populations of S. renifolius in Korea were confirmed to be diploid (2n = 30) and shared the most recent common ancestor with the other diploid species, S. nipponicus. Second, two recently described species, S. nabekuraensis and S. egorovii, were deeply embedded within S. renifolius in Japan and Korea, respectively, and their distinct taxonomic status requires further assessment. Finally, two intercontinental disjunction events in the subfamily, one in Lysichiton Schott between eastern Asia and western North America and the other in Symplocarpus between eastern Asia and eastern North America, were estimated to be between 4.5 and 1.4 million years ago (Pliocene and Pleistocene) and between 1.9 and 0.5 million years ago (Pleistocene), respectively.