广东小脆柄菇属的研究初报

本文报道了广东小脆柄菇属Psathyrella(Fr) Qulet 17个种,其中1个新种,15个国内新记录。新种是近变小脆柄菇Psathyrella subincerta Bi sp.nov.。文中有分种检索表。     

中国小脆柄菇属已知种类及其分布

对中国小脆柄菇属(Psathyrella)真菌进行了整理、修订,对有关分类学问题进行了讨论。中国小脆柄菇属真菌共51个名称记录,分布于26个省(自治区)。其中有18个分类单元引证了标本,2个记录的报道未提供形态描述,2个种存在错误拼写。     

中国环柄菇属一新种

发表中国环柄菇属一新种 ,即红鳞环柄菇 (LepiotasquamulosaB .TolgoretY .Li) ,模式标本存放在吉林农业大学菌物标本馆 (HMJAU)。     

环柄菇属东亚一新记录种——锥鳞环柄菇

报道东亚环柄菇属的—个新记录种——锥鳞环柄菇Lepota jacobi Vellinga ＆ Knudsen,标本采自中国云南。该种的鉴别特征是菌盖密被灰色至暗褐色的锥状鳞片;担孢子椭圆形,腹部近平直,极小;囊状体缺如。     

利用环介导等温扩增技术快速可视化检测肉褐鳞环柄菇

为了实现对肉褐鳞环柄菇科学、快速的物种鉴定,利用环介导等温扩增（LAMP）技术建立了快速检测肉褐鳞环柄菇的方法,即基于肉褐鳞环柄菇ITS序列设计并验证了一套特异性引物,为进一步缩短反应时间,并增强颜色差异优化了反应体系（Bst DNA聚合酶加入量0.5μL,Mg2+浓度3 mmol/L,HNB浓度180μmol/L,时间45 min,温度65℃）。结果表明:设计的引物特异性强,检测限低（7.56 pg/μL）,可在60 min内通过肉眼观察羟基萘酚蓝的颜色变化判定检测结果。说明利用低成本的LAMP技术能够简单快速、灵敏准确地检测出肉褐鳞环柄菇。     

环柄菇属东亚一新记录种———锥鳞环柄菇

报道东亚环柄菇属的一个新记录种———锥鳞环柄菇Lepiota jacobi Vellinga & Knudsen, 标本采自中国云南。该种的鉴别特征是菌盖密被灰色至暗褐色的锥状鳞片; 担孢子椭圆形, 腹部近平直, 极小; 囊状体缺如。     

采自吉林省的中国光柄菇属新记录

报道采自吉林省的中国光柄菇属 Pluteus新记录3种,即球盖光柄菇P. podospileus、波扎里光柄菇P. pouzarianus和汤姆森光柄菇P. thomsonii,并根据我国的材料提供详尽的形态描述和线条图。研究标本存放在吉林农业大学菌物标本馆（HMJAU）。     

广东光柄菇属一新种

本文报道广东地区光柄菇属 Pluteus Fr.7个种,其中1个新种及5个国内新纪录。新种是南光柄菇 Pluteus australis Bi sp.nov.。     

环柄菇属两中国新记录种

报道了环柄菇属距孢环柄菇组的2个中国新记录种:红斑环柄菇(Lepiota erythrosticta)和黄栗环柄菇(Lepiota luteocastanea).根据中国的标本对其特征进行了详细的描述,并就重要显微特征进行绘图,讨论了它们与相近种的区别,总结了其分布、生境等特点.     

白黄小脆柄菇发酵液中的一个新的血苋烷型倍半萜（英文）

从白黄小脆柄菇(Psathyrellacandolleana)发酵液提取物的乙酸乙酯层中分离得到一个新的血苋烷型倍半萜(1)和一个已知的没药烷型倍半萜(2)。通过质谱、核磁等方法确定化合物1的结构为15-hydroxy-drimenol。通过文献对照核磁数据确定化合物2为1α-hydroxy-bisabola-2,10-dien-4-one。     

The mushroom family Psathyrellaceae: evidence for large-scale polyphyly of the genus Psathyrella

Psathyrella is the archetypal little brown mushroom genus with few easily discernable characters causing it to be considered a "clean-up" genus for other small brown-spored saprotrophic species found worldwide. While molecular studies have demonstrated that mushroom genera based on homoplastic morphological characters are artificial, the degree of phylogenetic heterogeneity contained within Psathyrella and Psathyrellaceae has never been appropriately addressed. For this study, 132 ribosomal sequences from approximately one-tenth of the known Psathyrella species worldwide, including representatives of most subgeneric subdivisions, and three closely related coprinoid genera (Parasola, Coprinopsis, Coprinellus) were evaluated using multiple phylogenetic methods, including likelihood, with Agaricaceae as the outgroup. Our results indicated that Psathyrella was polyphyletic. Conservatively, the genus can be separated into 11 clades of which five can be raised to generic status. Most species of Psathyrella, including its type species P. gracilis, formed a large clade with Coprinellus, which appeared to be derived from within Psathyrella. Generic limits of Parasola, Lacrymaria, and Coprinopsis should be reevaluated. Several taxa previously synonymized based on morphological features were phylogenetically distinct. Morphological features traditionally used to subdivide Psathyrella appeared to be mostly convergent (homoplasious) when traced upon the resulting phylogenies, although several had high RI values. These results were interpreted in light of the two major taxonomic treatments of Psathyrella and revealed substantial inconsistencies between the molecular- and morphology-derived inferences of relationships.     

三种鳞伞属(Pholiota)真菌的菌丝生物学特性初步研究

研究了多脂鳞伞(Pholiota adiposa)、翘鳞伞(P.squarrosa)和多脂翘鳞伞(P.squarroso-adiposa)三种鳞伞属真菌的菌丝生物学特性。结果表明,多脂鳞伞和翘鳞伞菌丝生长的最适碳源为麦芽糖;多脂翘鳞伞最适碳源为蔗糖和麦芽糖。多脂鳞伞和翘鳞伞最适氮源均为牛肉膏和酵母膏;而多脂翘鳞伞最佳氮源为酵母膏和蛋白胨。三种菌丝生长的最适温度均为25℃。多脂鳞伞在pH值6~8均生长良好,最适pH值7~8,偏碱性;翘鳞伞和多脂翘鳞伞最适pH值均为6~7。     

刈割干扰下内蒙古草原两种丛生禾草繁殖策略的适应性调节

刈割是内蒙古草原的主要利用方式之一。当植物面对刈割干扰时, 可以通过繁殖策略的调节适应变化的环境。研究刈割干扰下植物繁殖策略的调节对于揭示植物的适应与进化机制具有重要意义。为此, 选择内蒙古典型草原的大针茅(Stipa grandis)和糙隐子草(Cleistogenes squarrosa), 在1979年围封的羊草(Leymus chinensis)样地(对照)和毗邻的长期刈割区对其繁殖策略进行了研究。结果显示: 1)长期刈割干扰下, 大针茅的种群生物量与对照区无显著差异, 由于其株丛生物量显著降低, 大针茅种群生物量的维持得益于种群密度的显著增加。糙隐子草的种群生物量比对照区显著提高, 由于其株丛生物量与对照区无显著差异, 糙隐子草种群生物量的增加也是因为密度的显著提高。因此, 密度调节是两种植物应对长期刈割干扰的重要的调节机制。2)长期刈割干扰下, 两种植物在无性繁殖和有性繁殖过程所采取的密度调节策略并不相同。大针茅种群生殖株丛的密度无显著变化, 非生殖株丛的密度显著提高, 导致其非生殖株丛的相对密度显著增加, 而生殖株丛的相对密度显著降低。因此刈割干扰下大针茅种群在密度调节上采取了保持有性繁殖株丛密度, 增加无性繁殖株丛密度的策略。糙隐子草种群非生殖株丛的密度显著增加, 但生殖株丛的密度增加幅度更大, 导致其非生殖株丛的相对密度显著降低, 而生殖株丛的相对密度显著提高。因此刈割干扰下糙隐子草种群在密度调节上采取了增加无性繁殖株丛密度的同时, 更大幅度地增加有性繁殖株丛密度的策略。3)长期刈割干扰下, 两种植物对生物量生殖分配的调节采取了不同的策略。大针茅株丛生物量向生殖枝分配的比例无显著变化, 通过降低生殖枝向穗的生物量分配比例, 降低了对有性生殖过程的生物量分配的投入; 而糙隐子草则通过增加株丛生物量向生殖枝分配的比例, 维持生殖枝向穗的生物量分配比例, 从而增加了对有性繁殖过程生物量分配的投入。4)长期刈割干扰下, 大针茅的株丛面积和株丛分蘖数与对照区无显著差异。糙隐子草株丛面积降低, 但是株丛分蘖数无显著变化。本实验说明, 植物种群有性繁殖和无性繁殖之间的密度调节和资源分配调节是草原植物应对刈割干扰下的重要调节机制, 不同的响应策略影响着植物种群的消长动态。     

A new species of Psathyrella (Agaricales,Coprinaceae) from Mexico with discussions on the known species

Psathyrella hypertropicalis, a new species, is described from a high mountain (Cofre de Perote) in the State of Veracruz, Mexico above the subtropical zone. This species is intermediate betweenP. velutina of the temperate regions andP. sepulchralis from the subtropical regions of Mexico. A list of the 26 species ofPsathyrella of Mexico is presented, of which 21 are from the tropics and subtropics, three from the temperate regions (P. velutina, P. spadicea, andP. hypertropicalis), and two with a broad distribution (P. candolleana andP. disseminata). Eleven are only known from Mexico.     

Species-specific response of photosynthesis to burning and nitrogen fertilization

The present study was conducted to examine photosynthetic characteristics of three dominant grass species (Agropyron cristatum, Leymus chinensis, and Cleistogenes squarrosa) and their responses to burning and nitrogen fertilization in a semiarid grassland in northern China. Photosynthetic rate (Pn), stomatal conductance (gs), and water use efficiency (WUE) showed strong temporal variability over the growing season. C. squarrosa showed a significantly higher Pn and WUE than A. cristatum and L. chinensis. Burning stimulated Pn of A. cristatum and L. chinensis by 24-59% (P＜0.05) in the early growing season, but not during other time periods. Light-saturated photosynthetic rate (φmax) in A. cristatum C. squarrosa. The burning-induced changes in soil moisture could explain 51% (P=0.01) of the burning-induced changes The stimulation of Pn under N fertilization was mainly observed in the early growing season when the soil extractable N content was significantly higher in the fertilized plots. The N fertilization-induced changes in soil extractable N content could explain 66% (P=0.001) of the changes in Pn, under N fertilization. The photosynthetic responses of the three species indicate that burning and N fertilization will potentially change the community structure and ecosystem productivity in the semiarid grasslands of northern China.     

Four new species of Calathea (Marantaceae) from French Guiana

Four new species are described: Calathea erecta, C. dilabens, C. granvillei , and C. squarrosa , based on material from French Guiana. Calathea erecta and C. granvillei are known also from the central Amazon Basin. Calathea squarrosa probably also occurs in Surinam. Calathea dilabens is presently known only from French Guiana, but probably occurs in adjacent Brazil and Surinam. A tentative key is provided to the species of Calathea known to occur in French Guiana.     

High mycorrhizal specificity in a widespread mycoheterotrophic plant, Eulophia zollingeri (Orchidaceae)

Because mycoheterotrophic plants fully depend on their mycorrhizal partner for their carbon supply, the major limiting factor for the geographic distribution of these plants may be the presence of their mycorrhizal partner. Although this factor may seem to be a disadvantage for increasing geographic distribution, widespread mycoheterotrophic species nonetheless exist. The mechanism causing the wide distribution of some mycoheterotrophic species is, however, seldom discussed. We identified the mycorrhizal partner of a widespread mycoheterotrophic orchid, Eulophia zollingeri, using 12 individuals from seven populations in Japan, Myanmar, and Taiwan by DNA-based methods. All fungal ITS sequences from the roots closely related to those of Psathyrella candolleana (Coprinaceae) from GenBank accessions and herbarium specimens. These results indicate that E. zollingeri is exclusively associated with the P. candolleana species group. Further, the molecular data support the wide distribution and wide-ranging habitat of this fungal partner. Our data provide evidence that a mycoheterotrophic plant can achieve a wide distribution, even though it has a high mycorrhizal specificity, if its fungal partner is widely distributed.