猪笼草吃虫不盖盖

猪笼草,是一类十分奇特的食虫植物,共有７０种左右,广泛分布在东南亚、印度、斯里兰卡及非洲的马达加斯加和澳大利亚北部,其中只有一种分布到我国的海南省和广东省南部,即猪笼草（Ｎｅｐｅｎｔｈｅｓｍｉｒａｂｉｌｉｓ）。猪笼草的叶十分有趣,其下部为叶片状,中部变成卷须状,而上部变成为圆筒形的瓶状体,瓶状体上还有一个盖。由于猪笼草的瓶状体内壁上密生腺体,能分泌消化液并引诱昆虫进入其内,当昆虫落入瓶底后则被其消化液浸死,进而被消化吸收和利用,这是植物捕杀昆虫的典型例子。因此,猪笼草常作为科普教育的材料。必须指…     

中国黄耆属一新种

多年生草本,高2—5厘米,密被开展的中着叉状毛。根木质化,直伸,灰褐色。茎极短缩,不明显。奇数羽状复叶,长3—4厘米,具短叶柄,有小叶10—13对;小叶椭圆形,灰绿色,长4—5毫米,两面被开展的毛,下面毛较密;托叶下半部合生,上部披针形,被开展的毛。总状花序具与叶近等长的总梗,密被开展的长毛。有花3—4朵;苞片披针形,有毛;萼筒状,不膨大,长约1厘米,被开展的白色长毛和混生少量的黑毛,萼齿钻状。长为萼筒的1/2;花冠黄色,旗瓣片近提琴形,长约2厘米,近顶部稍狭,顶端微凹,中部缢缩,下部渐狭成瓣柄,翼瓣与旗瓣近等长,瓣片长圆形,下部有耳,较瓣柄短;龙骨瓣短于翼瓣,瓣柄显著长于瓣片;二体雄蕊,子房线形,近于无柄,有毛;荚果未见。花期5——6月。本种与七叶黄耆A.heptapotamtuus     

三七的胚状体发生和植株再生

植物名称:三七(Panax notoginseng)。材料类别:茎、叶柄、叶。培养条件:(1)诱导愈伤组织和胚状体发生培养基为MS 2,4-D0.5—1.0mg/L(单位下同)(2)胚状体成苗培养基为M8 BAI GA1。培养温度26士1℃,愈伤组织诱导至胚状体发生过程为暗培荞;胚状体成苗为光培养,每日光照10小时,光照度1000～1500lx。生长与分化情况:取还未完全展开幼叶的小苗,按常规消毒后,以茎、总叶柄、小叶柄和叶外植体分别切成小段或小块,切段长度为0.5～0.7cm,叶片切块面积为0.7～1.0cm~2,接种于培养基(1)中,     

安徽碎米荠属一新种

多年生草本,植株高20-35厘米,根状茎粗壮,垂直的,无匍厘茎。茎直立,自基部分枝,有疏柔毛。基生叶柄长3-10厘米,羽状复叶具1对小叶,顶生小叶近圆形,长1.2-3厘米,宽1.4-3.5厘米,边缘圆钝齿,基部浅心形,侧生小叶小而同形,小叶柄长约0.5厘米;茎生叶叶柄长1.5-6厘米,羽状复叶具1-2对小叶,顶生小叶圆形或卵形,长1.5-3厘米,宽1-3厘米,边缘具圆钝齿,基部心形或楔形,侧生小叶小而同形,无小叶柄,全部小叶上面散生贴伏的短毛,下面无毛。     

猪笼草形态结构及食性的观察

通过对猪笼草的实地观察及实验,对其形态结构及食性有了进一步的了解。证实了昆虫掉入猪笼草瓶体后,瓶盖不会自动关闭的事实;发现了猪笼草既养蚊又食蚊的现象;还对猪笼草在维持生态平衡中的重要作用进行了讨论,提出应加强保护。     

观叶植物佳品——马拉巴栗与春羽

马拉巴栗(Pachira macrocarp),别名瓜栗、中美木棉,在台、港、粤等地又称之为“发财树”。木棉科瓜栗属乔木,原产于热带美洲。株高3—5米,树皮光滑,幼树树干常瓶状增粗。叶互生,密生于小枝顶端,掌状复叶,小叶5—7片,倒卵状椭圆形至披针形,中间一片最大,长28厘米,宽8厘米,叶柄长20厘米。花单生于叶腋间,淡黄绿色至淡黄色。蒴果。花期5月,果熟期10—12月。     

七叶树的栽培技术与开发利用

七叶树 ( Aesculuschinensis Bge)又名梭椤树、娑罗树、梭罗树、梭椤子、索罗果、开水果、开师粟 ,为七叶树科 ( H ippocastanaceae)落叶乔木。因叶片掌状复叶 ,小叶 5～ 9,常为 7个而得名。小枝粗壮 ,顶芽大。掌状复叶对生 ,小叶倒卵状长椭圆形或长椭圆状披针形 ,小叶柄长 5～ 1 7mm,总叶柄长 5～ 1 8cm。直立密集圆锥花序顶生 ,长 3 0～ 45 cm,总轴粗状 ,长 6～ 1 4cm;花小 ,白色 ,杂性同株 ,两性花生于花序下部 ,雄花生于上部 ;花萼筒形 ,花瓣 4,不等大 ,白色 ,上面 2瓣常有桔红色或黄色斑纹 ;雄蕊 7。子房上位 ,3室 ,每室有胚珠 2。蒴…     

安徽蔷薇科新植物

<正> 与原变种的区别在于叶柄较长,长5—10厘米,顶生小叶柄长2厘米,顶生小叶先端长尾尖,基部心形,花梗较短,长1.5—3厘米,子房微具腺毛。     

山东盐肤木属新植物

落叶灌木或小乔木,高2-5米;树皮灰色,不裂;小枝粗壮,密被黄褐色绒毛,有少数红褐色圆形皮孔,芽密被褐黄色绒毛。叶互生,连叶柄长14-32厘米,叶柄长4-8厘米,奇数羽状复叶,有小叶3-4(-5)对,叶轴具窄翅,每对小叶间距1.5-4.5厘米,叶轴与叶柄密被黄褐色绒毛;小叶对生,无柄或几无柄,生于叶轴上部的较大,卵状椭圆形或椭圆形,长6-12厘米,宽4-7厘米,先端急尖,基部不对称,宽楔形或圆形,顶生小叶的基部渐窄成翅柄,上部的1(-2)对小叶基部下侧常与叶轴之翅连结,无柄,中上部边缘具疏钝锯齿,上面平滑,除中脉和侧脉具褐色短柔毛外,余处无毛或几无毛,下面密被黄褐色绒毛,中、侧脉和细脉在叶面下陷,在叶背隆起。     

金樱子的识别要点

金樱子株高可达5米,具倒钩状皮刺和刺毛。单数羽状复叶互生,小叶多为3,有时5;小叶片椭圆状卵形,革质。春末夏初开花,花单生于侧枝顶端,白色,芳香。花梗与萼筒均密被刺毛。花托膨大,瓶状;     

EARLY LEAF ONTOGENY AND SHOOT DEVELOPMENT IN BROWNEA ARIZA (LEGUMINOSAE)

Brownea ariza Benth. (Leguminosae: Caesalpinioideae) shows early shoot tip abortion and subsequent renewal growth from the pseudoterminal bud. This species is unusual in that the entire shoot system is formed before flushing from the bud occurs, shoot tip abortion occurs during flushing, and the aborting portion contains three to six leaves as well as primordial structures varying from hood to peg shape. This study focused on the morphological changes from initiation of scale and foliage leaf primordia in the “resting” renewal bud through bud elongation to flushing and bud abortion. Scanning electron microscopy revealed that embryonic scale leaves are hood-shaped while foliage leaf primordia show early segmentation into leaflets and stipules. No transitional stages were observed. Bud scales and foliage leaves show opposite developmental trends. In bud scales, length at maturity increases from first to last formed, while length decreases in sequentially formed foliage leaves. Early in leaf development the stipules keep pace with the elongation of the rachis. When the bud reaches about one half of its final length the leaf rachis begins to exceed the lengths of its stipules. This young rachis terminates in a distinct mucro that persists until maturity at which time it abscises. Growth patterns indicate that mucro and rachis are a single developmental unit. The early abortion of a shoot tip containing several leaves cannot be easily rationalized. Previous suggestions have involved maintenance of form and ecological adaptation. We add the possibility of elimination of cell progeny encumbered by mutations. From this and other studies of this group, it is clear that at maturity leaves of different species may look alike, e.g., Hymenaea and Colophospermum are bifoliolate; Brownea, Saraca, and others are multifoliolate. However, early stages of leaf ontogeny are quite diverse and may be of systematic value, since these early differences are lost or masked by later development.     

The mutant crispa reveals multiple roles for PHANTASTICA in pea compound leaf development

Pinnate compound leaves have laminae called leaflets distributed at intervals along an axis, the rachis, whereas simple leaves have a single lamina. In simple- and compound-leaved species, the PHANTASTICA (PHAN) gene is required for lamina formation. Antirrhinum majus mutants lacking a functional gene develop abaxialized, bladeless adult leaves. Transgenic downregulation of PHAN in the compound tomato (Solanum lycopersicum) leaf results in an abaxialized rachis without leaflets. The extent of PHAN gene expression was found to be correlated with leaf morphology in diverse compound-leaved species; pinnate leaves had a complete adaxial domain of PHAN gene expression, and peltate leaves had a diminished domain. These previous studies predict the form of a compound-leaved phan mutant to be either peltate or an abaxialized rachis. Here, we characterize crispa, a phan mutant in pea (Pisum sativum), and find that the compound leaf remains pinnate, with individual leaflets abaxialized, rather than the whole leaf. The mutant develops ectopic stipules on the petiole-rachis axis, which are associated with ectopic class 1 KNOTTED1-like homeobox (KNOX) gene expression, showing that the interaction between CRISPA and the KNOX gene PISUM SATIVUM KNOTTED2 specifies stipule boundaries. KNOX and CRISPA gene expression patterns indicate that the mechanism of pea leaf initiation is more like Arabidopsis thaliana than tomato.     

Role ofLLD, a new locus for leaflet/pinna morphogenesis inPisum sativum

Properties of a mutant at theLLD (LEAF-LET DEVELOPMENT) locus in peaPisum sativum L. are reported in this paper. Plants homozygous for the Mendelian recessive mutationlld bear leaves in which a few to many leaflets are incompletely developed. Opposite pinnae of rachis nodes often formed fused incompletely developed leaflets. Thelld mutation was observed to abort pinna development at almost all morphogenetic stages. Thelld mutation demonstrated high penetrance and low expressivity. The phenotypes oflld plants intl, tac, tl tac, tl af andtl af tac backgrounds suggested that LLD function is involved in the separation of lateral adjacent blastozones differentiated on primary, secondary and tertiary rachides and lamina development in leaflets. The aborted development of tendrils and leaflets inlld mutants was related to deficiency in vascular tissue growth. The morphological and anatomical features of the leaflets formed on atl lld double mutant permitted a model of basipetal leaflet development. The key steps of leaflet morphogenesis include origin of the lamina by splitting of a radially symmetrical growing pinna having abaxial outer surface, opposite to the vascular cylinder, through an invaginational groove, differentiation of adaxial surface along the outer boundary of split tissue in the groove and expansion of the lamina ridges so formed into lamina spans.     

14C Translocation pathways in honeylocust and green ash: Woody plants with complex leaf forms

Long-distance transport in plants requires precise knowledge of vascular pathways, and these pathways differ among species. This study examines the ¹⁴C translocation pathways in honeylocust (Gleditsia triacanthos L.) and green ash (Fraxinus pennsylvanica Marsh.), species with compound leaves, and compares them with those of cottonwood (Populus deltoides Bartr. ex Marsh.), a species with simple leaves. The stem vasculature of honeylocust conforms to a 2/5 helical phyllotaxy and that of green ash to a decussate phyllotaxy. The plastochron is relatively long in both species – 2.5+ days in honeylocust and 4.5+ days in green ash. Consequently, the transition from upward to downward translocation from mature source leaves is abrupt and occurs close to the apex. Export of ¹⁴C from localized treatment positions within a leaf was found to vary both quantitatively and spatially. To determine export patterns, ¹⁴CO₂ was administered to either individual leaflets of once-pinnate or pinnae of bipinnate leaves of honeylocust, and to either individual veins of simple or leaflets of compound leaves of green ash. Transections of either the petiole or rachis base were then examined for ¹⁴C by micro-autoradiography. In all cases, as treatment positions advanced acropetally in the leaves, the bundles translocating ¹⁴C were situated more dorsally in the basal petiole and rachis vasculatures. ¹⁴C was confined to the right side of the vasculature when structures on the right side of a leaf were treated. Compound leaves of both species mature acropetally. Thus, mature basal pinnae of honeylocust and basal leaflets of green ash translocate acropetally to younger leaf parts that are still rapidly expanding. All translocation pathways, both in the stem and leaf, conformed with vascular organization previously determined by anatomical analyses.     

Assessing the Feasibility of Biofuel Production from Lignocellulosic Banana Waste in Rural Agricultural Communities in Peru and Colombia

Banana cultivation is widespread in tropical and subtropical regions where many rural agricultural communities exist. The banana plant bears fruit once in its life cycle, leaving behind a significant amount of usable agricultural residue. Current practice leaves this residue to decompose in the field spreading diseases and polluting water supplies. We evaluated the technological feasibility of converting lignocellulosic banana residue to ethanol as a localized biofuel production strategy to improve the livelihoods of rural agricultural communities in Peru and Colombia. Liquid hot water (LHW) and steam explosion pretreatment followed by saccharification and fermentation using commercial cellulolytic enzymes and yeast strain were evaluated for three different lignocellulosic residues independently (pseudostems, leaves, and rachis). Stems and rachis, with higher glucan conversion, appeared more promising for biofuel production than leaves (up to 93 and 77 % glucose yields for rachis and pseudostems, respectively). Steam explosion pretreatment allowed higher glucan conversion for stems and leaves, while LHW was better suited for rachis. Pseudostem is the most abundant residue generated with 306,000 tons/year in Uraba Province (Colombia) and 15,000 tons/year in the Chira Valley (Peru) on a dry weight basis. Potential ethanol production in the Chira Valley was estimated in 4.8 and 76.8 ML year^?1 in Colombia, processing stems and rachis combined. This study indicated that there is potential for biofuel production using the lignocellulosic banana residue, which could be expanded to other banana growing communities around the world. Process improvements such as increasing solids loading, water recycling, and optimizing fermentation are still required.     

INDETERMINATE GROWTH OF LEAVES IN GUAREA (MELIACEAE): A TWIG ANALOGUE

Leaves of seed plants are generally characterized as organs of determinate growth. In this regard, Guarea and related genera seem unusual in that the pinnately compound leaves of these plants contain a bud at their tip from which new pinnae expand from time to time. Previous studies (based upon superficial examinations of leaf-tip buds) have produced contradictory conclusions regarding how long the leaf apex remains meristematic and produces new pinna primordia. In order to determine whether leaf development in Guarea is truly indeterminate, we microscopically examined leaf-tip buds of G. guidonia and G. glabra. In both species, the leaf apex remains meristematic and continues to produce new pinna primordia as the leaf ages. Unexpanded leaves of G. guidonia contained an average of 23 pinna primordia, while the oldest leaves we examined had initiated an average of 44 total pinnae. In G. glabra, unexpanded leaves contained 8 pinnae, whereas an average of 28 pinnae had been initiated on the oldest leaves. These results indicate that leaf development in Guarea is truly indeterminate. Periodic examination of individual intact leaves indicated that the leaves commonly continue their growth for 2 or more years (observed maximum = 51 months). As new leaflets are initiated at the shoot apex (and subsequently expand in rhythmic flushes), older (basal) leaflets may abscise. In addition, the petiole and rachis of the leaf thicken and become woody as a result of the activity of a vascular cambium. Guarea leaves therefore seem to function as the analogue of a typical twig (stem) in general habit as well as in their indeterminate apical growth and secondary thickening.     

A new species of Leptocycas(Zamiaceae)from the Upper Triassic sediments of Liaoning Province,China

A new cycad,Leptocycas yangcaogouensis sp.nov.,was found in sediments from the Late Triassic in western Liaoning,China.The pinnately compound leaves(Pseudoctenis type)are screwed in a crown on the stem top.The leaflets are linear,with parallel veins and decurrent bases on the rachis.The leaf bases are persistent.The cataphylls intermix with the leaves.The female cone is ovoid in shape.The characteristics of the new plant are more similar to those of Leptocycas gracilis,a Triassic cycad from North America,but the new species differs from L.gracilis in the size of its stem(7-8 vs.3-5 cm in diameter,respectively),leaves(length × width 100 × 16 vs.30 × 7 cm,respectively)and leaf density along the stem(4-6 vs.1-2 bases/1 cm length,respectively).Both L.gracilis and L.yangcaogouensis,having leaves of the Pseudoctenis type,show a closer relationship to the extant Dioon of Zamiaceae.The present study provides evidence for the origin of the genus Dioon,which may have come from Leptocycas plants of the Triassic.It would be assumed that the extent cycads in Zamiaceae originate from the pteridosperms in the Late Paleozoic and have evolved through the stage of L.gracilis and L.yangcaogouensis in Late Triassic,and reaching the extant Dioon.     

Foliar Nectaries in Mahogany (Swietenia Jacq.)

The pinnately compound leaves of Swietenia spp. have numeroussmall nectaries on petiole, rachis, petiolules, and both surfacesof all leaflets. Nectaries are circular to elongate, eitherlevel with the epidermis or slightly raised or depressed. Thesecretory surface is usually smooth even under high SEM magnification.Each nectary has an outer zone of three or four cell layersof slightly elongate and densely cytoplasmic cells subtendedby two layers of rounded cells with thickened walls and lightlystaining cytoplasm. Proximity of nectaries to vasculature isvariable and seems to be only fortuitous. Meliaceae, Swietenia, mahogany, nectary anatomy, extrafloral nectaries, foliar nectaries     

The impact of two gall-forming arthropods on the photosynthetic rates of their hosts

The impact of herbivores on host plant photosynthetic rates can range from negative to positive. While defoliation by chewing herbivores can result in increases in photosynthesis followed by compensatory growth, other herbivore guilds, such as mesophyll feeders which damage photosynthetic leaf tissues, almost always reduce photosynthetic rates. The impact of galling herbivores on host photosynthesis has rarely been examined, even though the limited tissue disruption and the strong metabolic sinks induced by gall-forming herbivores could potentially stimulate photosynthetic rates. I examined the hypothesis that gall-inducing herbivores could stimulate photosynthesis in neighboring leaves in response to increased sink-demand by the gall. To address this hypothesis, I measured photosynthetic rates of galled leaves or leaflets, neighboring ungalled leaves or leaflets, and ungalled leaves or leaflets on ungalled shoots on naturally growing Prunus serotina (wild cherry) and Rhus glabra (smooth sumac). The leaves of wild cherry were galled by an eriophyid mite, Phytoptus cerasicrumena; the leaves of smooth sumac by an aphid, Melaphis rhois. I found that both species reduced the photosynthetic rates of the leaves or leaflets they galled from 24 to 52% compared to ungalled leaves in ungalled areas of the plants. Contrary to my hypothesis, mite galls on wild cherry reduced photosynthesis of neighboring ungalled leaves within the same shoot by 24% compared to ungalled leaves on gall-free shoots. Aphid galls on sumac leaflets did not significantly alter the photosynthetic rates of neighboring leaflets relative to ungalled leaves on ungalled shoots. Although gall-formers would appear to have the potential to stimulate photosynthesis in the same manner as defoliating herbivores, i.e., by increasing sink demand relative to source supply, I found only negative impacts on photosynthesis. I suggest that sink competition for nutrients between developing leaves and growing gall tissue may account for the negative impacts of sink-inducing gallers on photosynthesis. Received: 17 October 1997 / Accepted: 2 February 1998