Antibiosis and antixenosis to Aphis gossypii (Homoptera: Aphididac) in Colocasia esculenta

Fifty cultivars of taro, Colocasia esculenta (L.) Schott (Araceae), collected from islands in Micronesia and Polynesia, eight cultivars from the University of Hawaii's taro germplasm collection, and a closely related aroid, Xanthosorna sagittifolium (L.) (Araceae), were screened for antibiosis and antixenosis to Aphis gossypii Clover. Life history data for A. gossypii were collected by assessing survivorship and fecundity of aphids caged on taro leaves in the field. Significant differences in aphid reproductive rate and longevity were observed among the taro cultivars, and cultivars were ranked from most resistant to most susceptible. Antixenosis was assayed in the laboratory in a multiround choice test where A. gossypii were offered four leaf discs excised from different taro cultivars. Additionally, field observations of aphid abundance on taro cultivars were made to corroborate clip cage studies and laboratory experiments. 'Iliuaua','Rumung Mary','Maria', 'Ketan 36', and'Agaga' were the most resistant in terms of reducing aphid fecundity and survivorship, whereas the Iliuana,'Purple', 'TC-83001', and 'Putih 24' were least preferred in aphid choice tests. X. sagittifolium consistently exhibited strong aphid resistance. Resistant cultivars identified in this study may form the basis of breeding programs seeking to combine aphid resistance with other desirable agronomic traits in taro.     

The major tuber storage protein of araceae species is a lectin. Characterization and molecular cloning of the lectin from Arum maculatum L.

A new lectin was purified from tubers of Arum maculatum L. by affinity chromatography on immobilized asialofetuin. Although this lectin is also retained on mannose-Sepharose 4B, under the appropriate conditions free mannose is a poor inhibitor of its agglutination activity. Pure preparations of the Arum lectin apparently yielded a single polypeptide band of approximately 12 kD upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. However, N-terminal sequencing of the purified protein combined with molecular cloning of the lectin have shown that the lectin is composed of two different 12-kD lectin subunits that are synthesized on a single large precursor translated from an mRNA of approximately 1400 nucleotides. Lectins with similar properties were also isolated from the Araceae species Colocasia esculenta (L.) Schott, Xanthosoma sagittifolium (L.) Schott, and Dieffenbachia sequina Schott. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration of the different Araceae lectins have shown that they are tetrameric proteins composed of lectin subunits of 12 to 14 kD. Interestingly, these lectins are the most prominent proteins in the tuber tissue. Evidence is presented that a previously described major storage protein of Colocasia tubers corresponds to the lectin.     

Hybridisation and fruit formation in macabo cocoyam (Xanthosoma sagittifolium (L.) Schott)

Studies on the floral morphology of macabo cocoyam (Xanthosoma sugittifolium (L.) Schott) indicated that it required 50 to 70 days for flower formation while fruit maturity took 40 to 60 days after pollination. Among the three types of cocoyams (“white”, “red” and “yellow”), male flowers were more sterile in the “red” and “yellow” types. The spadix consisted of three parts, a bottom pistillate section, a central constricted region with sterile flowers separating the pistil from a third staminate section. The fruiting head formed as a result of hybridisation, is dome shaped and is comprised of a dense cluster of berries. Mean number of berries per fruiting head was 244 ± 40 while the weight of each head was 16.15 ± 6.38 gm. There were an average of 15 ± 6 seeds per berry with 100 seeds weighing 0.0266 ± 0.0048 gm. The longitudinally shaped seed is ridged and grooved like a pumpkin pod when observed under high magnification (400 ×)     

A semi-lunar periodicity of neurotransmitter-like substances from plants

Cardioacceleratory activity was found in ethanolic extracts of the leaves of Coleus blumei (Benth, var. verschaffeltii), Phaseolus vulgaris L., and Philodendron (Schott) sagittifolium. The cardioacceleratory activity fluctuated considerably from day to day and from sample to sample but displayed a consistent tendency to drop to very low levels shortly after full moon and new moon. The tendency to fall to low levels at semi-lunar intervals is compared with similar findings in cockroach, mouse and human blood and complementary findings in cockroach nervous tissue.     

The phenology of leaf life spans in woodland populations of the ferns Dryopteris filix-mas (L.) Schott and D. dilatata (Hoffm.) A. Gray in Derbyshire

WILLMOT, A., 1989. The phenology of leaf life spans in woodland populations of the ferns Dryopteris filix-mas (L.) Schott and D. dilatata (Hoffm.) A. Gray in Derbyshire. The results of a survey on the number of upright fronds per plant in a population of Dryopteris filix-mas and in a population of D. dilatata over a 14 month period are presented. These coupled with similar information on the number of developing fronds per plant demonstrate that large plants in the population of each species were summergreen, while small ones were wintergreen. This size-specific difference in leaf phenology does not seem to have been recorded before in Dryopteris filix-mas. It is suggested that this difference, in both species, may have been due to either the different environments in which the plants grew or to a risk-sensitive strategy in the small plants. It is considered that such a strategy might be concerned with the obtaining or retention of resources at a critical period in the life history of the species.     

中国珍珠菜属(报春花科)一新种——右旋过路黄

对新种右旋过路黄Lysimachia dextrorsiflora X. P. Zhang, X. H. Guo &; J. W. Shao进行了描述和绘图。该新种产于中国安徽和福建, 因茎匍匐, 叶对生, 花黄色, 单生叶腋与过路黄L. christinae Hance近缘, 但其花冠裂片在蕾期右旋(顺时针)旋转排列(俯视), 花梗通常长于叶片与叶柄长之和, 花期4月初至5月初而不同。     

Infrared thermography ofArum lily inflorescences

The infrared radiation emitted from the surface of inflorescences of 12 aroid species was monitored with an infrared camera, capable of 0.1°C resolution, and the data were converted to temperature values by means of temperature reference standards. Images representing surface temperatures were obtained forAmorphophallus bulbifer Blume,A. campanulatus Blume,A. forbesii Engl. et Gehrm.,A. rivieri Dur.,Philodendron selloum Koch,Monstera deliciosa Liebm.,Dracunculus vulgaris Schott,Arum italicum Mill.,A. dioscoridis Sibth.,A. creticum Boiss et Heldr.,Caladium sp., andRemusatia vivipara Schott. These images were different among species with respect to temperature, duration of detectable heat development, and organ type (male and female flowers, spathe and appendix) found to be thermogenic. All these species, however, exhibited three common characteristics: 1) production of heat by the male flowers; 2) pollen-shedding immediately after heat production had ceased; and 3) when male flowers were some distance away from female flowers along the spadix, heat was not detected in female flowers. Heat emission was associated with the alternative, cyanide-insensitive pathway that was fully operative.     

山西蕨类植物新资料

报道了山西省新记录的蕨类植物6种1变种,隶属6科、7属,它们是井栏边草、东方狗脊、贵阳铁角蕨、雅致针毛蕨、沼泽蕨、毛轴假蹄盖蕨和高大耳蕨.     

中国玉叶金花属一新记录种——长瓣玉叶金花

报道中国茜草科(Rubiaceae)玉叶金花属一新记录种——长瓣玉叶金花(Mussaenda longipetala H. L. Li)。该种在形态上与尾裂玉叶金花(M. caudatiloba D. Fang)和狭瓣玉叶金花(M. lancipetal X. F. Deng & D. X. Zhang)相似,但区别在于叶片长圆状卵形或椭圆状卵形,托叶早落,正常的萼裂片长6~8 mm,花冠管长约3 cm,裂片披针形,长约12 mm。目前仅知分布于越南北部的广宁省和中国的广西北部湾沿海地区。凭证标本存放于广西植物标本馆(IBK)。     

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; )     

Nanocnide zhejiangensis sp. nov. (Urticaceae: Urticeae) from Zhejiang Province,East China

Nanocnide zhejiangensis X.F. Jin & Y.F. Lu, a new species of Urticaceae from Zhejiang, east China, is described with illustrations. The new species is morphologically similar to Nanocnide japonica in having staminate inflorescence longer than leaves, but differs by having glabrous stems, petioles, peduncles and abaxial leaf surfaces, glabrous perianth lobes of staminate flowers, dorsally glabrous perianth lobes of pistillate flowers, and acuminate or solitary spinose–setaceous at the apex. Analysis based on ITS, atpF–H, atpB–rbcL and trnL–F sequences also demonstrate that Nanocnide japonica is the closest extant relative to the new species.     

中国黄梅属地衣的初步订正

本文是作者对中国黄梅属地衣从形态与化学两方面进行比较研究之后的初步订正。研究结果表明,文献中所记载的中国 Parmelia conspersa Ach. 实际上为Xanthoparmeliatinctina(Mah.et Gillet)Hale及X.mexicana (Gyeln.)Hale的误用名称;长白山的Parmeliasubramigera Gyeln. 则为X. mexicana的误用名;Parmelia stenophylla(Ach.)Heug.及Parmeliasubconspersa Nyl为X. taractica(Krempb.)Hale的误用名;Parmelia vagans (Nyl.)Nyl.为X.camtschadalis(Ach.)Hale的误用名。此外,文中还报道了新组合一种,新变种一个,中国新记录一种。     

中国枝孢属的分类研究ⅩⅪ.萝藦枝孢新种和二新记录种

本文报道枝孢属一新种：萝藦枝孢CladosporiummetaplexisZ.Y.ZhangetX.Y．Wang,Sp．nov．和二个新记录种：叶生枝孢槭变种C.eriphyllum（Pers．）Martinvar.acerinumSaccardo和绳状枝孢C.funiculosumYamamoto。新种附有拉丁文描述及形态图,模式标本保存于云南农业大学真菌标本室（MHYAU）。     

Overexpression of Df4CL1 from Dryopteris fragrans Enhances Flavonoids and Lignin Production in Transgenic Tobacco

Russian Journal of Plant Physiology - Dryopteris fragrans (L.) Schott is a fern in the family Dryopteridaceae that shows a good curative efficacy against several skin diseases, such as psoriasis...     

构树雌雄株叶片解剖结构特征的比较研究

为了研究雌雄异株植物构树（Broussonetia papyrifera（L.） Vent.）的性别差异,以其叶片为材料,采用石蜡切片法,对其主要解剖结构特征进行观察和比较。结果显示：（1）构树雌、雄株叶片解剖结构组成一致,均由表皮、叶肉组织和叶脉3部分组成。其上、下表皮均由一层细胞构成,具有较厚的角质层及丰富的表皮毛,叶肉中栅栏组织高度发达,此外,维管系统在叶中所占比例很大;（2）构树雌、雄株叶片细胞大小及厚度在各类型组织间存在一定差异,雄株叶片上表皮厚度、栅栏组织厚度、主脉维管束木质部厚度及维管束厚度均显著大于雌株叶片,且在栅海比、组织结构紧密度、组织结构疏松度和主脉维管束木质部面积占维管束的比例等方面也与雌株有极显著差异。研究结果表明构树叶片的解剖结构不仅具有旱生植物叶片的典型特征,而且还表现出明显的性别差异,这可能与构树雌、雄株的生殖分配有关。     

Xanthosoma sagittifolium tubers contain a lectin with two different types of carbohydrate-binding sites

An unusual lectin possessing two distinctly different types of carbohydrate-combining sites was purified from tubers of Xanthosoma sagittifolium L. by consecutive passage through two affinity columns, i.e. asialofetuin-Sepharose and invertase-Sepharose. SDS-polyacrylamide gel electrophoresis, N-terminal amino acid sequencing, and gel filtration chromatography of the purified lectin showed that the X. sagittifolium lectin is a heterotetrameric protein composed of four 12-kDa subunits (alpha(2)beta(2)) linked by noncovalent bonds. The results obtained by quantitative precipitation and hapten inhibition assays revealed that the lectin has two different types of carbohydrate-combining sites: one type for oligomannoses, which preferentially binds to a cluster of nonreducing terminal alpha1,3-linked mannosyl residues, and the other type for complex N-linked carbohydrates, which best accommodates a non-sialylated, triantennary oligosaccharide with N-acetyllactosamine (i.e. Galbeta1,4GlcNAc-) or lacto-N-biose (i.e. Galbeta1,3GlcNAc-) groups at its three nonreducing termini.     

Detection of Xylella fastidiosa in potential insect vectors by immunomagnetic separation and nested polymerase chain reaction

A sensitive and specific assay for detecting Xylella fastidiosa in potential insect vectors was developed. This assay involves immunomagnetic separation of the bacteria from the insect, followed by a two-step, nested polymerase chain reaction (PCR) amplification using previously developed oligonucleotide primers specific to X. fastidiosa . A total of 347 leafhoppers representing 16 species were captured and sampled from American elm ( Ulmus americana L.) trees growing in a nursery where bacterial leaf scorch caused by X. fastidiosa occurs. Two of these leafhopper species, Graphocephala coccinea and G. versuta , regularly tested positive for X. fastidiosa using this technique. These insects are therefore potential vectors of X. fastidiosa . Using immunocapture and nested PCR, it was possible to detect as few as five bacteria per sample.