Structure of the unusual explosive fruits of the early diverging angiosperm Illicium (Schisandraceae s.l., Austrobaileyales)

All Illicium spp. have explosive fruits, which is a unique character among the basal grade of angiosperms. Illicium fruits consist of several ventrally dehiscing follicles developing from conduplicate carpels, with a prominent, slightly postgenitally fused ventral slit. The closure of the ventral slit is also secured by two mirror‐symmetrical massive longitudinal sclerenchymatous bands in the mesocarp along the edges and by turgor pressure. The pericarp differentiates into a fleshy (or coriaceous) peripheral zone (exocarp and mesocarp) with numerous ethereal‐oil‐containing cells and a sclerenchymatous (single‐layered, palisade) inner zone (endocarp). Dehydration of the fleshy zone of the pericarp and partial compression of the epidermal sclereids with U‐shaped wall thickenings lining the ventral suture are instrumental in explosive fruitlet dehiscence. Generally, the fruit structure of Illicium differs dramatically from those in other early diverging angiosperms. Gynoecium and fruit structure (and a probable early Cretaceous divergence from the Schisandra‐Kadsura clade) provide evidence for treatment of Illicium as separate from Schisandraceae s.s. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013 , 171 , 640–654.     

扁桃幼果发育的形态解剖学研究

以普通扁桃品种‘纸皮’为研究对象,观察测定了扁桃幼果生长发育动态,并采用石蜡切片法研究了扁桃幼果发育过程。结果表明,扁桃幼果鲜重、体积及果径增长均呈单“S”曲线。大体可分为3个生长时期,增长速率为:第Ⅱ期>第I期>第Ⅲ期。扁桃果实由单心皮上位子房发育而成,边缘胎座,横生胚珠。果皮由外果皮、中果皮和内果皮构成:外果皮是一种复合结构,由表皮毛和表皮细胞组成;中果皮主要是由薄壁细胞和分布其中的维管束组成;内果皮也有丰富的维管束组织分布,其木质化顺序由外向内。中果皮细胞分裂终止早于内果皮。     

A remarkable new species of Salacia (Celastraceae: Salacioideae) from the Western Ghats,India

A new species of Salacia is described from Karnataka and Kerala states of the Western Ghats, India. It is unique within the genus on account of its obliquely dehiscing anthers and 7–10 cm long, prolate to broadly ellipsoid or ovoid, keeled, greenish-yellow 5- to 8-seeded fruit with thin epicarp and dry mesocarp. Salacia megacarpa sp. nov. can be grouped with S. fruticosa Heyne ex M.A.Lawson and S. oblonga Wight & Arn. which are the only other species from the sub-continent which exhibit axillary, ramiflorous, dichotomously branched cymes.     

The ontogeny and structure of the pericarp and seed-coat of Harpephyllum caffrum Bernh. ex Krauss (Anacardiaceae)

The exocarp sensu lato , which develops from the outer epidermis and adjacent parenchyma of the ovary wall, consists of collenchyma cells with a stomatous epidermis. The fleshy, parenchymatous mesocarp or sarcocarp develops after endocarp differentiation. The endocarp is partly spongy and partly woody. The spongy endocarp contains most of the vascular tissue and fills the cavities and grooves of the intricately sculptured outer woody endocarp. The inner woody endocarp and adjacent woody, endocarpal operculum develop from the inner epidermis and subepidermal parenchyma of the ovary wall. The bitegmic, anatropous ovule develops into a derived, exalbuminous seed with an undifferentiated seed-coat. An extensive chalaza, extensive hypostase sensu lato and the raphe are important in the development of the seed-coat. The pericarp and seed-coat of H. caffrum is compared with those of Sclerocarya birrea subsp. caffra and Lannea discolor . The close phylogenetic relationship of these three species of the Spondieae is reaffirmed. The marked similarities in pericarp and seed structure between H. caffrum and species of the genus Spondias are noted.     

Correlations among fruit traits and evolution of different fruits within Melastomataceae

The anatomy and morphology of nearly mature fruits in 85 mainly palaeotropical species of Melastomataceae were examined using microtome- and hand-sectioning, and differential staining. Much structural heterogeneity was observed in both capsules and berries. Mul-tivariate analyses of 31 of the 52 characters recorded for each species, revealed that indehiscence is associated with fusion of ovary and hypanthium tissues, placenta persistence, lack of a persistent endocarp, and a dearth of srlereids in these tissues, while dehiscenre is correlated with the opposite states and a persistent exocarp. Other fruit characters such as lignification or fleshiness of tissues do not show a consistent association with dehiscence. Break down of broad fruit types, such as 'berry' and 'capsule', into their individual morphological and anatomical traits shows how unusual fruit types, such as woody berries, fleshy capsules, and capsules containing fleshy placentas (display fruits), which are common in palaeotropical Melastomeae and Dissochaeteae, contribute to a loosening of expected correlations. Thus, discriminant analysis clearly differentiated display fruits from the other fruit types because of their combination of fleshy placentas with a persistent endocarp and absence of ovary/hypanthium fusion. The evolution of fruit types within Melastomataceae, and especially Dissochaeteae, and their reliability as phylogenetic indicators is discussed in the light of molecular phylogenies for these groups that show that berries and capsules evolved several times independently, explaining the observed heterogeneity of outwardly similar fruits. Fruit diversity within Melastoma , a monophyletic genus of 22 species, provides an example of the plasticity afforded by the particular construction of Melastomataceae fruits, which has contributed to ecological diversification in melastome seed dispersal.     

矮樱桃果实发育的解剖学研究

利用石蜡制片法解剖研究魏樱桃果实的发育过程,将其发育过程分为３个时期：（１）果实细胞旺盛分裂和增大期：外果皮细胞垂周分裂,以增加果实表面积;中果皮和内果皮主要进行平周分裂３以增加细胞层数,同时３层果皮的细胞体积也增大。（２）内果皮细胞硬化期：外果皮和中果皮的细胞停止分裂,体积增大也不明显,内果皮细胞壁逐渐加厚、硬化。９３）中果皮细胞显著增大期：中果皮的细胞的体积弦向增大的同时,径向延长更明显。其成     

Characterization of peroxidases in lignifying peach fruit endocarp

Developing peach (Prunus persica L. Batsch `Redskin') fruit were used to characterize the role of peroxidases in lignification. During development, the endocarp of these drupes becomes lignified while the mesocarp remains parenchymatous. Acidic peroxidase from lignifying endocarp were similar to those of the fleshy mesocarp. The endocarp had a larger amount and number of basic peroxidases than the mesocarp. Cultured peach leaf cells are thought to be lignified because their walls give a positive reaction with phloroglucinol-HCI. These cells also secreted a basic peroxidase. Peroxidases were difficult to extract from endocarp tissue as they lignified. This was also demonstrated by tissue printing on nitrocellulose. Flesh, but not endocarp peroxidase was evident in tissue prints. This suggests that tissue printing may fail to reveal the presence of enzymes which are firmly attached to the cell.     

槐属分类系统的修订

自《槐属的研究》一文发表后,作者对本属植物的地理分布特点、主要形态特征和某些化学物质的演化趋势及其与临近属的相互关系等作了综合分析研究。结果表明:本属植物的演化趋势是由乔木→灌木或亚灌木→草本;羽状复叶→近掌状复叶或单叶;托叶有逐步退化趋势,小托叶有→无;顶生圆锥花序→多种着生的总状花序;花萼裂片连合程度逐步增加,小苞片有→无;荚果果皮构造及质地也呈进行性退化趋势,即果皮从三层完整果皮向二层过渡,质地肉质→木质→革质或近革质,开裂方式由不开裂→豆科典型的二瓣开裂→本属特有的四瓣开裂。金雀花碱在本属植物中出现较早,在肉果亚属已有较多种类含有此碱,并随着植物的进化而含有种类在逐步减少,而苦参碱在本属植物中出现的较晚,肉果亚属的植物只有少数种类含有此碱,裂果亚属含此碱的种类较多,并随着植物的进化而含有种类在逐步减少。据此,作者提出了本属植物的系统树,并对本属各分类群的系统位置作了全面修订与补充。     

Pericarp anatomy of wild roses (Rosa L., Rosaceae)

The pericarp anatomy of representatives of all subgenera and sections of the genus Rosa was studied. All species have the same basic pericarp structure: it is composed of inner and outer endocarps, mesocarp and exocarp formed by the epidermis and hypodermis. The differences concern mainly the thickness of particular layers, and the shape and size of their cells. Cells of the endocarp and mesocarp are thick-walled. The only exception is Rosa rugosa mesocarp, which is composed of rather thin-walled cells with a large lumen. The endocarp structure of Rosa achenes resembles the drupe of the genus Prunus s.l. and drupelets of Rubus species.     

Unusual Network of Internal Phloem in the Pod Mesocarp of Cowpea [Vigna unguiculata (L.) Walp. (Fabaceae)]

A mycelium-like network of internal phloem was observed in theinner mesocarp of the lateral pod walls of the fruit of certaingenotypes of cowpea [Vigna unguiculata (L.) Walp.] In the cultivarVita 3, the network consists of single, or rarely double, strandsof sieve elements and associated phloem parenchyma, orientedmainly parallel with the fibres of the adjacent endocarp, andstretching marginally beyond the sheets of fibres to connectabove and below with the outermost phloem of the longitudinalstrands of the dorsal and ventral sutures of the fruit. Theinternal phloem network does not relate conformationally to,or interconnect with the conventional (xylem+phloem) vasculatureof the mid mesocarp of the pod wall. In Vita 3, sieve elementsdifferentiate in the internal phloem after those in the majorveins of the pod, but before the presumptive endocarp fibrescommence wall thickening. The pod walls of twenty-one otherspecies of legumes proved negative for internal phloem, whileof nine varied genotypes of cowpea examined, six proved positive,three negative for the trait. Presence of internal phloem incowpea is not always associated with presence of endocarp fibresor necessarily with large fruits with large seeds. Possiblefunctions suggested for the phloem network are to provide assimilatesfor fibre wall thickening or to transport solutes to or fromsites of temporary storage in the fleshy inner layers of thepod wall. Internal phloem, legume fruit, translocation, mesocarp, pod wall, Vigna unguiculata, cowpea     

Anatomical development of the pericarp and seed of Oncidium flexuosum Sims (ORCHIDACEAE)

Interpretation of the anatomical structure of the ovary and fruit of the Orchidaceae family is still controversial, which makes it difficult to understand the development and dehiscence of the fruit. The genus Oncidium is polyphyletic and is currently the subject of taxonomic studies. In this study, we have investigated the anatomical development of the pericarp and seed of Oncidium flexuosum Sims to determine important diagnostic characters that, along with molecular data, can assist in defining this group. We have found a new anatomical characteristic of the family: the presence of precursor cells for fruit dehiscence, which were visible from the beginning of development and located on the outer walls of the sterile valves. In contrast with what has been observed by different authors with other species, in the mature fruit of O. flexuosum, only the endocarp of the fertile valves and a few cells near the exocarp and the vascular bundle in the sterile valves show parietal thickening, while the rest remains parenchymatous. During the development of the ovule and embryo, we have shown that the embryonic sac of this species has eight nuclei and that the embryo has a long and elaborate suspensor.     

Localization of beta-D-glucosidase activity and glucovanillin in vanilla bean (Vanilla planifolia Andrews)

The morphology, anatomy and histology of mature green vanilla beans were examined by light and transmission electron microscopy. Beans have a triangular cross-section with a central cavity containing seeds. Each angle is lined with tubular cells, or papillae, while the cavity sides consist of placental laminae. The epicarp and endocarp are formed by one or two layers of very small cells, while the mesocarp contains large, highly vacuolarized cells, the cytoplasm being restricted to a thin layer along the cell walls. The radial distributions of glucovanillin and beta-glucosidase activity, measured on p-nitrophenyl-beta-glucopyranoside and glucovanillin, are superimposable and show how beta-glucosidase activity increases from the epicarp towards the placental zone, whereas glucovanillin is exclusively located in the placentae and papillae. Subcellular localization of beta-glucosidase activity was achieved by incubating sections of vanilla beans in a buffer containing 5-bromo-4-chloro-3-indolyl-beta-d-glucopyranoside as a substrate. Activity was observed in the cytoplasm (and/or the periplasm) of mesocarp and endocarp cells, with a more diffuse pattern observed in the papillae. A possible mechanism for the hydrolysis of glucovanillin and release of the aromatic aglycon vanillin involves the decompartmentation of cytoplasmic (and/or periplasmic) beta-glucosidase and vacuolar glucovanillin.     

Morphology and anatomy of blackberry pyrenes (Rubus L., Rosaceae) Elementary studies of the European representatives of the genus Rubus L.

This article presents the results of studies on the pyrenes of selected European brambles belonging to different subgenera and sections of the genus Rubus. Differences between the pyrenes of particular species are mainly visible in their shape, size and the outer endocarp sculpture. Numerous SEM photographs revealed that the differentiation of the endocarp surface is due to variations in a thin layer of transition sclereids developing between the outer endocarp and a mesocarp parenchyma. The endocarp structure of the genus Rubus can be used in determining some species belonging to different subgenera, even if generally its significance in the taxonomy of the European Rubus is limited.     

无距虾脊兰果实发育及其解剖学特征

以授粉后无距虾脊兰不同发育阶段的蒴果为材料,对果实生长动态进行研究,并用石蜡切片法进行果实结构研究。观察结果表明：无距虾脊兰果实授粉至授粉后40 d生长速度最快。果实由3心皮组成,横切面为6瓣,3瓣有胎座,3瓣无胎座,开裂后6瓣于顶端连接。发育的过程中,果皮细胞层数及果实内外表皮细胞体积不变,果实直径的增加主要来自于细胞平周分裂和中果皮细胞体积的增大。果实成熟时只有少数细胞有细胞壁增厚现象,开裂线的前体细胞细胞壁发生木质化并向不同方向收缩导致果实的开裂。     

The generic position of Lithraea brasiliensis Marchand (Anacardiaceae): evidence from fruit and seed structure

In Lithraea brasiliensis Marchand the exocarp is characterized by brachysclereids and the parenchymatous mesocarp by large secretory ducts; inner sclerenchymatous ridges are absent in die mesocarp. The stratified endocarp s. s. comprises a crystal layer, palisade-like brachysclereids, osteosclereids and macrosclereids. The osteosclereids are characterized by a distinct light line or linea lucida , which has hitherto also been recorded in a species of Rhus. In the partially pachychalazal seed, a typical Anacardiaceae-like hypostase typifies the chalazal part of the seed coat, while the integumentary seed coat reveals a well preserved outer epidermis, a compressed endotegmen and well developed inner cuticular layer. Our comparison of die characters of the ovule, fruit and seed of L. brasiliensis with those of various species of Rhus and other genera of the tribe Rhoeae (some closely related) presents evidence that L. brasiliensis could be most closely associated with the genus Rhus.     

Development and structure of the drupe in Sclerocarya birrea (Richard) Hochst. subsp. caffra Kokwaro (Anacardiaceae), with special reference to the pericarp and the operculum

The development and structure of the exo-, meso- and endocarp of the drupe of Sclerocarya birrea subsp. caffra were examined. The mature exocarp comprises the outer epidermis with stomata and lenticels, subepidermal collenchyma and parenchymatous layers with secretory canals. This exocarp sensu lato develops from the outer epidermis and the outer layers of the ovary wall. The fleshy parenchymatous mesocarp or sarcocarp also contains secretory tissue. The mesocarp develops after endocarp differentiation and lignification. The developmental sequence within the pericarp corresponds to the general pattern in drupes. The endocarp or sclerocarp, which is not stratified, consisting mainly of brachysclereids, fibres and vascular elements, develops from the inner epidermis and adjacent tissue of the young ovary wall including the procambium strands. The operculum represents a well-defined part of the endocarp. Early in its development a parenchymatous zone already clearly demarcates the operculum. The literature on the pericarp of the Anacardiaceae drupe is discussed to establish the diagnostic value of these morphological characteristics for future taxonomic studies.     

Sternopygus castroi,a new species of Neotropical freshwater electric fish,with new synapomorphies to the genus (Sternopygidae: Gymnotiformes: Teleostei)

Sternopygus castroi n. sp. is described as a new species of sternopygid Neotropical freshwater fish from the Rio Cuieiras, tributary of Rio Negro, Amazonas State, Brazil. It differs from the other species of the genus by a combination of characters. Three new synapomorphies for Sternopygus are reported. Only Sternopygus species present a membranous integumental subopercular fold originating postero-ventrally in the opercular region, running anteriorly to the isthmus region. In Sternopygus, the membranous opercular opening is wide and S-shaped (wide but fleshy in Gymnotus). In Sternopygus there is also a medial cephalic fleshy fold at the ventral margin of the opercular membrane, directed forward and ventrally to the isthmus, surrounding the anal pore anteriorly, just behind the subopercular flap.     

Flower fertilization and fruit development prompt changes in free polyamines and ethylene in damson plum (Prunus insititia L.)

The flower opening of damson plum (Prunus insititia L.) was accompanied by an increase in the content of free-polyamines (PA) in the sepals, petals and sex organs, the ovary being most active in accumulating spermine (Spm). The fertilization process and senescence brought on a decline in ovarian Spm, but stimulated putrescine (Put) and spermidine (Spd) content in the sepals. The endocarp of this climacteric fruit produced only ethylene at the end of the S1 phase and throughout S2, in which there was a great richness in ACC and MACC. The greatest amounts of ACC and MACC were observed in the ripening mesocarp and epicarp. The contribution of the endocarp and epicarp to the total ACC in the developing fruit was very similar. During flowering and S1 and S2 phases, Spd was the most abundant PA; in contrast, during S3 and S4 Put was most abundant. The mesocarp contributed the most to the total content in PA throughout the fruit development. The control of SAM distribution towards ethylene and/or PA appears to differ during the development of the endocarp, as the only peak of free-Put (detected in S2) coincided with the highest ACC accumulation and ethylene production. On the contrary, in S3 it is probable that SAM was transformed preferentially into PA, given that free-Spd and Spm, hardly detectable in S1 and S2, peaked in this phase in which there was no gas production.     

‘兰箭3号’箭筈豌豆荚果发育动态及腹缝线结构研究

箭筈豌豆(Vicia sativa)是高海拔地区重要的一年生豆科牧草,但荚果成熟时的开裂现象会造成种子的严重损失。该研究以栽培品种‘兰箭3号’为对象,对其荚果在发育过程中的形态特征、水分含量、腹缝线表面结构及腹缝线横截面解剖结构的动态变化进行观察分析,以探讨箭筈豌豆荚果的裂荚机理,为生产中确定种子收获的适宜时间提供理论依据。结果显示:(1)‘兰箭3号’约在盛花后25~30d荚果变为浅棕色,此时荚果已完成生理成熟,且荚果的大小和干重均达到最大值,含水量降到最小值;盛花后25d荚果腹缝线出现裂缝,盛花后35d腹缝线完全裂开。(2)‘兰箭3号’于盛花后20d腹缝线处离层细胞开始解体;盛花后25d,内、中、外果皮的薄壁细胞均开始失水皱缩,其中内果皮的薄壁细胞部分已开始破裂,离层细胞及其下面的薄壁细胞完全解体,外部果瓣缘细胞内侧细胞壁破裂,但外侧异常加厚的细胞壁仍然保持完整并连接两个果瓣,使荚果不开裂;盛花后30~35d,内、中、外果皮的薄壁细胞完全失水,细胞壁皱缩在一起,同时外部果瓣缘细胞外侧细胞壁断裂成两部分,荚果的两个果瓣裂开。研究表明,盛花后25~30d荚果失去绿色变为浅棕色时是‘兰箭3号’的适宜收获时间,且离层和细胞失水产生的机械拉力是导致箭筈豌豆荚果开裂的主要原因,推测外部果瓣缘细胞外侧增厚融合的细胞壁很可能是‘兰箭3号’抵抗裂荚的关键结构。