Herbarium survey on the genus Azolla (Salviniaceae) in Italy: distributive and taxonomic implications

An analysis of Italian herbarium specimens belonging to the genus Azolla was carried out using optical microscope and SEM techniques. According to recent international reviews, three micro-morphological characters have been considered for the specimen analysis: (i) number of leaf trichome cells, (ii) septation of glochidia and (iii) features of the macrospore perine. The analysis of the patterns concerning both vegetative and reproductive characters was complicated by the relatively low number of sporulated specimens stored in the Italian Herbaria. The analysis of the selected specimens showed the presence of two well distinct systematic groups. One group was characterized by bicellular leaf trichomes, pluriseptate glochidia and not-warty perine, traits that permitted to taxonomically attribute it to A. cristata. The second group was characterized by monocellular leaf trichomes, non-septate or uniseptate glochidia and warty perine, so that it could be taxonomically attributed to A. filiculoides Lam. This study confirmed the large use in the past of the name ‘A. caroliniana’ to indicate the species actually named A. cristata. In Italy, this species was found to be collected only in the past, while A. filiculoides was found to be present with both ancient and recent herbarium specimens.     

Plant functional group responses in an African tropical forest recovering from disturbance

Background: Newly protected, tropical forests recovering from logging and clearance are increasingly important targets for conservation. Recovery is typically evaluated or monitored by using a few easily identified species groups, but this may not be sufficient as unmonitored groups of equivalent ecological importance are unlikely to respond in a similar manner due to physiological or dispersal differences.

Aims: We compared four groups of plants: large trees, shrubs and saplings, herbs and ferns in a forest recovering from disturbance. We quantified the relative importance of disturbance history and local environmental conditions in determining species richness and community composition of these groups and assessed whether the groups could act as surrogate indicators for one another.

Methods: Vegetation was surveyed on a gradient of disturbance intensity and recovery time (20–60 years) in Mabira Forest, Uganda. We looked for correlations between species groups in richness or composition across sites and used constrained ordinations to identify important environmental variables.

Results: Neither species richness nor composition patterns were correlated between groups. All groups were weakly related to disturbance history; trees and shrubs were related to soil, herbs to microhabitat and ferns to microclimate.

Conclusions: No group acted as an indicator for another. The relative influence of disturbance and local environmental effects varied in the manner predicted, with disturbance stronger for trees and environment stronger for ferns.     

A new species in the Elaphoglossum petiolatum complex (Elaphoglossaceae) from Mexico

Elaphoglossum trichomidiatum is described from northeastern Mexico. The new species is a member of theE. petiolatum comples, which is widespread in tropical America, Africa, Southeast Asia, and the Pacific Islands. It is unique in the complex and in sectionLepidoglossa in bearing trichomidia on the abaxial blade surface.     

海南岛蕨类植物新资料

记录海南蕨类植物新分布15种,这15种植物是毛叶粉背蕨(Aleuritopteris squamosa)、光脚短肠蕨(Allantodia deoderleinii)、淡绿短肠蕨(Allantodia virescens)、台湾车前蕨(Antrophyum formosanum)、岭南铁角蕨(Asplenium sampsonii)、薄叶阴地蕨(Botrychium daucifolium)、黑足鳞毛蕨(Dryopteris fuscipes)、太平鳞毛蕨(Dryopteris pacifica)、爪哇鳞始蕨(Lindsaeajavanensis)、黑鳞剑蕨(Loxogramme assimilis)、网脉海金沙(Lygodium subareolatum)、三轴凤尾蕨(Pteris longipes)、翠绿凤尾蕨(Pteris longipinnula)、布郎卷柏(Selaginella braunii)和高雄卷柏(Selaginella repanda)。海南现有蕨类植物已达到约450种(包括变种)。     

福建梅花山观赏蕨类植物资源及其开发利用

对闽西梅花山国家级自然保护区的观赏蕨类植物资源进行调查,发现具有观赏价值的野生蕨类植物29科48属68种。对该区各种观赏蕨按观赏用途分为园林绿化、盆景配置、切花配叶和盆栽观赏等4个别类,并对其种类组成、垂直分布、水平分布与生态分布、优势资源以及利用途径进行分析,同时提出开发利用建议。     

Development of EST‐SSRs from the Alpine Lady‐fern,Athyrium distentifolium

The utility of EST‐simple sequence repeats (EST‐SSRs) was evaluated in the fern Athyrium distentifolium. From 1152 frond cDNA clones, 165 microsatellites, including di‐, tri‐, tetra and penta‐nucleotide repeat motifs, were identified. Primer design was possible for 74 of the SSRs; subsequent screening of 10 loci on 186 individuals from six natural populations revealed between two and seven alleles per locus and expected heterozygosity (H_E) estimates ranging from 0.027 to 0.809. Eight of these loci were further examined for cross‐species and cross‐generic amplification in other Woodsiaceae species, and polymorphic products were detected. EST‐derived SSRs provide robust, informative and potentially transferable polymorphic markers suitable for biodiversity research.     

二回原始观音座莲蕨光合作用的生理生态学研究

利用 CO2 光合测定仪分析了引种栽培的二回原始观音座莲叶片的光合补偿点和光合饱和点及其日变化 ,通过控制叶室的光合有效辐射、CO2 浓度、温度和相对湿度 ,分析了叶片的羧化效率和 CO2 补偿点 ,并进行光合有效辐射 ,温度或相对湿度对光合速率的单因子影响研究。二回原始观音座莲的二回羽状复叶上午、中午和下午的光合补偿点分别为 6 .1、6 .4和 3.1μmol/m2 s,光合饱和点分别为 2 50、50 0和 2 50 μm ol/m2 s。最适光合有效辐射为 10 0～ 50 0μmol/m2 s。叶片的羧化效率为 0 .0 191,CO2 补偿点为 59.1μmol/m ol。光合速率在叶温 2 2～ 2 8°C范围内 ,随温度升高上升 ;2 8～ 33°C随温度升高下降 ,最适温度为 2 4～ 30°C。相对湿度 30 %～85%的试验范围内 ,叶片光合速率随湿度增加而增大 ,最适相对湿度条件在 75%以上。     

蕨类植物的VA菌根及其协同进化的初步研究

蕨类植物的ＶＡ菌根及其协同进化的初步研究赵之伟张涛和兆荣（云南大学生物系,昆明６５００９１）（云南大学生态地植物研究所,昆明６５００９１）ＳｔｕｄｉｅｓｏｎＶＡＭｙｃｏｒｒｈｉｚａｌＳｔａｔｅｏｆＰｔｅｒｉｄｏｐｈｙｔｅｓａｎｄＴｈｅｉｒＣｏｅｖｏ...