黑龙江省蜜环菌生物种的地理分布概况

自1999年至2002年间对黑龙江省境内几个主要林区中的蜜环菌生物种进行了调查、采集和鉴定,并对其寄主种类和子实体发生规律以及地理分布特点进行了总结分析。结果表明:黑龙江省境内至少存在5个蜜环菌生物种,即芥黄蜜环菌Armillaria sinapina,高卢蜜环菌A.gallica,黄盖蜜环菌A.luteopileata,奥氏蜜环菌A.ostoyae和中国生物种F;寄主包括10个针叶和阔叶树种;与其他几种蜜环菌生物种相比较,A.gallica是黑龙江省境内出现概率最大的一个生物种;根据采集经验发现,温度和湿度是影响子实体发生的主要因子。     

锡林河流域不同植被带土壤绿菌门微生物群落的空间分布特征

[目的] 为了探究锡林河流域中游不同植被带土壤绿菌门（Chlorobi）成员的空间分布特征及驱动因子。[方法] 本文选择典型河滨带环境为研究对象,沿河流中心至河流阶地（陆向）方向,在无植被带（BC）、水莎草沼泽（BS）、灯芯草沼泽化草甸（LF）、鹅绒委陵菜草甸（HF）、河流阶地羊草草原（LT）、丘陵坡地大针茅典型草原（HT）中分别采集0-10 cm土壤样品。基于16S rRNA基因高通量测序分析土壤绿菌门微生物群落的组成、丰度及空间分布特征;结合土壤理化因子分析绿菌门微生物群落空间异质性的驱动因子。[结果] 在属水平上共检测到来自绿菌目（Chlorobiales）和Ignavibacteriales目的9个类群。Chlorobiales1、2、6及Ignavibacteriales7、9类群的最高相对丰度低于0.40%;Ignavibacteriales3、4、5、8类群的最高相对丰度介于0.54%-1.06%。Chlorobiales1、2类群在HF、LT和HT的相对丰度显著高于BS（P<0.05）,Chlorobiales1类群的相对丰度与pH和总有机碳含量呈极显著正相关（P<0.01）;Chlorobiales2类群的相对丰度与粉黏粒含量呈极显著正相关（P<0.01）;Ignavibacteriales3、5、7、9和Ignavibacterium4类群在LF的相对丰度显著高于BC（P<0.05）,与含水量呈极显著正相关（P<0.01）;Chlorobiales6和Ignavibacteriales8类群在BS的相对丰度显著高于其他植被带（P<0.05）,与氨态氮含量呈极显著正相关（P<0.01）。变异权重分析表明,土壤含水量解释了绿菌门微生物群落空间变异的65.7%。[结论] 锡林河流域不同植被带土壤绿菌门微生物群落存在明显的空间异质性;土壤含水量是不同植被带绿菌门微生物群落空间异质性的主要驱动因子。     

卡伍尔氏链霉菌NA4突变株〖WTHX〗ΔbafAI的次级代谢产物研究

链霉菌产生的次级代谢产物是农用和医药抗生素的重要来源。为了更深入挖掘卡伍尔氏链霉菌NA4潜在多样的次级代谢产物,对阻断NA4主产物bafilomycins的突变株ΔbafAI随机激活的代谢产物进行分离和鉴定。采用HP20固相萃取、硅胶柱色谱、凝胶柱色谱以及半制备HPLC等方法对ΔbafAI代谢产物进行分离纯化;使用NMR和MS确定化合物结构,并对单体化合物进行了生物活性测定。共分离鉴定6个化合物：环（L-异亮氨酸-L-脯氨酸）（1）、环（L-缬氨酸-L-脯氨酸）（2）、环（L-脯氨酸-L-亮氨酸）（3）、环（L-脯氨酸-L-苯丙氨酸）（4）、（2E, 4E）-5-（3-羟苯基）-戊-2, 4-二烯酰胺（5）和5′-脱氧-5′-甲硫肌苷（6）。6个化合物均是阻断NA4主产物后非特异激活的或产量显著提高的化合物,均为该菌中首次分离;化合物5和6是第二次从天然提取物中分离得到;化合物1和2显示出抗白色念珠菌活性,并首次报道了化合物5的抗氧化活性。进一步丰富了卡伍尔氏链霉菌NA4次级代谢产物研究,为激活沉默或低表达次级代谢产物合成基因簇提供了有益借鉴。     

西藏青稞根际细菌群落结构及多样性

【目的】分析西藏不同种植区青稞根际土壤细菌群落结构及其影响因素，揭示特定环境下根际细菌生物标志物，为发掘研究优异根际促生菌及其作用提供参考。【方法】采用16S rRNA基因高通量测序技术和数据统计分析，比较了西藏5个市青稞种植区根际土壤细菌群落组成和结构差异，分析了青稞根际细菌生物标志物及群落结构变化的驱动因素。【结果】通过测序45个根际土壤样品获得10 715个操作分类单元（operational taxonomic units，OTUs），共43门、1 244属、2 783种，其中放线菌门（Actinobacteriota）、变形菌门（Proteobacteria）、绿弯菌门（Chloroflexi）、酸杆菌门（Acidobacteriota）、拟杆菌门（Bacteroidota）、厚壁菌门（Firmicutes）、芽单胞菌门（Gemmatimonadota）、粘球菌门（Myxococcota）和髌骨细菌门（Patescibacteria）为优势菌门，相对丰度占比94.92%-96.56%。五个市的根际细菌群落结构存在明显的差异，组间差异大于组内差异（R=0.226 9，P=0.001），其中放线菌门、绿弯菌门、酸杆菌门、拟杆菌门和髌骨细菌门丰度存在显著性差异（P<0.05）。五个市青稞根际土壤存在潜在生物标志物，拉萨和山南只有3个和6个特有细菌进化支，共现网络更为复杂、OTUs间联系更为紧密。变形菌门、绿弯菌门、放线菌门和酸杆菌门是青稞根际土壤中主要的关键细菌门，内生菌门、Methylomirabilota和蓝细菌分别是林芝市、日喀则市和山南市的特有关键类群。青稞根际细菌群落结构的变化主要与环境因子pH、全钾（total potassium，TK）、速效钾（available potassium，AK）、碳磷比（C：P）和海拔有关，其中TK是影响根际土壤细菌群落最重要的因子（r²=0.621 4，P=0.001）。【结论】西藏青稞根际细菌多样性丰富，5市间存在显著差异，且不同生长区青稞根际具有特有的生物标志物，为进一步研究特有根际细菌在青稞生长和环境适应中的作用，发掘优异根际促生菌提供参考。     

复合菌系降解玉米秸秆过程中群落演替与秸秆降解的关系

[目的] 为了获得木质素降解复合菌系LDC降解玉米秸秆的适宜条件,明确秸秆降解过程中可能发挥重要作用的功能微生物类群。[方法] 以培养温度、pH、培养基装液量和接菌量等单因素试验结果为依据,采用响应面法优化复合菌系降解玉米秸秆的培养条件,利用Miseq高通量测序技术,分析不同降解时期复合菌系的群落结构变化规律。[结果] 复合菌系对秸秆最佳降解条件为：培养温度32℃、初始pH为8.2、装液量为40%,接菌量为10%。此条件下木质素最大降解率为44.5%,相比未优化处理提高13.3%。在门水平上,变形菌门（Proteobacteria）、拟杆菌门（Bacteroidetes）和厚壁菌门（Firmicutes）是复合菌系LDC的优势菌门。在玉米秸秆降解过程中,降解初期的优势菌属为Proteiniphilum（11.9%）、Sphaerochaeta（8.4%）、Ruminofilibacter（8.4%）、Pannonibacter（6.7%）、Pseudomonas（6.1%）和Rhizobium（5.7%）;在降解高峰期时,Anaerocolumna（24.0%）、Caenispirillum（9.2%）和Thauera（7.0%）的丰度显著上升,分别是其在降解初期的16.5倍、3.0倍和5.9倍,而Ruminofilibacter（10.9%）的丰度仍然很高且排在第二位。在降解末期的优势菌属为Ruminofilibacter（25.4%）、Pseudomonas（9.7%）、Sphaerochaeta（8.8%）、Caenispirillum（8.4%）、Pannonibacter（4.3%）、Thauera（4.0%）以及Desulfomicrobium（3.4%）。[结论] 明确了玉米秸秆降解复合菌系的最佳培养条件以及在不同降解时期微生物群落结构变化规律,在玉米秸秆降解过程中发挥重要作用的微生物类群为Pseudomonas、Pannonibacter、Thauera、Ruminofilibacter和Anaerocolumna。     

成土时间对黄河三角洲植物及微生物演替的影响

受时空因素的限制,研究土壤、微生物和植物的演替过程通常采用以空间换时间的时空替代法,关于成土时间的驱动力研究较少。选取黄河三角洲4块代表性冲积区域（形成年代分别为1904-1929年,1929-1934年,1964-1976年和1976年至今）,由沿海到农田（1-40 km）设计采样路线,通过多样性调查、土壤采样、MiSeq测序等方法对陆地生态系统的植物、细菌和真菌多样性以及微生物功能组成进行了监测。结果表明,随成土时间的增加,植物物种丰富度和生物量显著提高（P<0.05）,低盐度指示物种白茅的分布区域向海岸推进;细菌群落酸杆菌门（Acidobacteriota）等3个门类占比显著增加,拟杆菌门（Bacteroidota）等12个门类占比显著减少（P<0.05）,涉及基因信息处理、核苷酸代谢等基础生命活动和光合作用的功能通路在年代最晚的扇区富集,而涉及细胞老化调控、外源物质生物降解与代谢、芳香化合物降解等功能的通路在年代最早的扇区富集（LDA score>2,P<0.05）;真菌群落涉及病理营养的捕虫霉门（Zoopagomycota）等类群相对丰度的显著增加（P<0.05）。耐盐菌、自养菌、反硝化菌、反硫化菌等功能群在成土较晚区域的丰富度较高,有促进成土初期土壤碳氮积累、土壤养分循环和有效性的提升的功能潜力,进而影响植物演替。成土时间还驱动适应高营养环境的类群对先锋类群比值的增大,促进微生物生态位的分化。研究表明成土时间是对黄河三角洲植物和微生物群落组成变化的重要而显著的驱动力,为提高评估滨海生态系统植物和微生物演替规律的准确性提供了科学依据。     

胡杨根际土壤来源放线菌分离及其拮抗活性筛选

根际土壤微生物在抵御病原微生物的入侵、提高植物的抗病能力等方面具有重要作用。胡杨作为沙漠地区的常见植物,其根际土壤微生物种类丰富且具有很高的研究价值。为了探究根际土壤微生物的作用,丰富和完善极端环境拮抗活性微生物菌种库,本研究基于选择培养基筛选法分析了新疆南疆地区10种不同地区的胡杨根际土壤的放线菌资源多样性,并采用细菌的16S rDNA测序和平板对峙法筛选。结果表明：经过分离与筛选,共获得269株菌株,选择生长状态较好的78株进行分析鉴定,分别为5个属,其中链霉菌属（Streptomyces）为优势类群。利用平板对峙法和琼脂扩散法以白色念珠菌（Candida albicans）、细极链格孢菌（Alternaria tenuissima）、大丽轮枝菌 （Verticillium dahliae）、尖孢镰刀菌（Fusarium oxysporum）、金黄色葡萄球菌（Staphylococcus aureus）、铜绿假单胞菌（Pseudomonas aeruginosa）、大肠杆菌（Escherichia coli）、肺炎克雷伯菌 （Klebsiella pneumoniae）、解淀粉欧文氏菌（Erwinia amylohydrolylic）、伤寒沙门氏菌（Salmonella typhi）为靶标菌,对分离出来的菌株进行拮抗活性检测,筛选出32株活性放线菌。这些结果丰富了微生物资源并为新疆主要农牧业病害的防控提供了菌种基础。     

河南卢氏和江西宜春两处锂矿山地表微生物群落分布特征差异及成因分析

[目的] 揭示地表锂矿石表面和风化产物中细菌群落多样性特征。[方法] 针对细菌16S rRNA片段扩增进行高通量测序,分析不同锂矿石表面及其风化产物中细菌群落组成、多样性及功能属性等信息。[结果] 河南卢氏南阳山伟晶岩型锂矿石和江西宜春花岗岩型锂矿石表面及其风化产物的细菌群落多样性有差异。南阳山伟晶岩矿石与其风化产物、宜春花岗岩矿石表面和风化产物（NK-1、NK-1F、YK-1、YK-1F、YK-2、YK-2F、YK-3）的OTUs分别是1010、540、835、828、1117、974和604,其差异与不同的矿物组成显著关联。两矿山均有其优势微生物,在门水平上,两矿山均以放线菌门（Actinobacteria）、变形菌门（Proteobacteria）为优势菌门。同时两矿区微生物群落组成具有显著差异性（P<0.05）,不同地理位置风化产物样本之间差异尤为显著（P<0.001）;在属水平上,NK-1中相对丰度大于5%的属为鞘氨醇单胞菌属（Sphingomonas）、马赛菌属（Massilia）;NK-1F为类芽孢杆菌属（Paenibacillus）、杆状细菌属（Bacillus）、马赛菌属（Massilia）;YK-1F为芽球菌属（Blastococcus）、念珠菌固体杆菌属（Candidatus-Solibacter）、Noviherbaspirillum属、伯克霍尔德氏菌属（Burkholderia-Caballeronia-Paraburkholderia）,YK-2为unidentified-Chloroplast属,YK-2F为北里孢菌属（Kitasatospora）,YK-3为1174-901-12属、甲基杆菌属（Methylobacterium）。不同地理位置的矿石及其风化物样本的功能注释均涉及代谢、遗传信息处理、环境信息处理等6个代谢通路。[结论] 16S rRNA高通量测序揭示不同地区锂矿石及其风化产物的细菌多样性存在差异,各具优势类群,样本间菌落组成、多样性及功能属性的差异与锂矿石化学组成、风化程度和地理分布密切相关。这项研究揭示了优势微生物类群的元素地球化学功能与含锂矿物地表风化的潜在联系,可为微生物生态分布研究及相关微生物资源开发提供新数据。     

松瘿小卷蛾及其寄生蜂对落叶松挥发物的嗅觉行为反应

为确定松瘿小卷蛾（Cydia zebeana）对寄主的定位习性,以及探讨对其的综合防治方法,通过Y型管嗅觉仪行为选择实验,分析松瘿小卷蛾及其两种寄生性天敌小卷蛾革腹茧蜂（Ascogaster olethreuti）和卷蛾长体茧蜂（Macrocentrus sp.）对寄主兴安落叶松（Larix gmelinii）的9种不同浓度挥发物的行为反应。结果表明,对雌蛾产生引诱作用的挥发物为3-蒈烯、水芹烯,产生驱避作用的挥发物为月桂烯、罗勒烯、莰烯;（R）-α-蒎烯表现为低浓度引诱高浓度驱避。对雄蛾产生引诱作用的挥发物为（S）-β-蒎烯,产生驱避作用的挥发物为月桂烯、3-蒈烯、（S）-α-蒎烯、莰烯。对小卷蛾革腹茧蜂有引诱作用的挥发物为（S）-β-蒎烯、（S）-α-蒎烯、叶醇,产生驱避作用的挥发物为罗勒烯、莰烯、水芹烯;对卷蛾长体茧蜂有引诱作用的挥发物为（S）-β-蒎烯、（S）-α-蒎烯、（R）-α-蒎烯、叶醇,产生驱避作用的挥发物为罗勒烯、水芹烯。说明在利用推拉策略防控松瘿小卷蛾时,月桂烯、叶醇和（S）-α-蒎烯可用于保护目标林,驱避害虫吸引天敌;水芹烯可以结合化学防治施用于饵木林,诱杀害虫而驱避寄生蜂。     

西藏麦地卡湿地大型土壤动物群落特征与环境因子关系

为了探究西藏麦地卡湿地国家级自然保护区大型土壤动物群落特征与环境因子的关系,于2020年7月和2021年8月根据其地理环境特征在其三个核心区共设置了3个样地（100 m×100 m）,每个样地设置2个样点作为重复;采用手检法收集大型土壤动物,并保存于75%乙醇的收集管中,圆筒式环刀（高30 cm,直径5 cm）取0~10 cm土样,测定相关环境因子。共捕获大型土壤动物336头,经鉴定隶属于3门5纲11目15科,优势类群为石蜈蚣科（Lithobiidae）、芫菁科（Meloidae）、拟步甲科（Tenebrionidae）;单因素方差分析显示,三个样地中,大型土壤动物个体数（F=0.194,P=0.833）、Shannon-Wiener多样性指数（H）（F=0.304,P=0.758）、Pielou均匀度指数（E）（F=0.346,P=0.732）和Simpson优势度指数（C）（F=0.245,P=0.797）均无显著性差异（P>0.05）。三个样地的Jaccard相似性系数（J）在0.56~0.65,为中等相似;功能类群以植食性为主,腐食性最少。Pearson相关性分析表明,Pielou均匀度指数（E）分别与海拔（Alt）和速效钾（RAK）呈极显著正相关（P<0.01）,Pielou均匀度指数（E）分别与土壤含水量（SWC）和全氮（TN）呈显著正相关（P<0.05）,个体数（N）与土壤盐度（SAL）呈极显著负相关（P<0.01）。     

Foreign exploration for Scirtothrips perseae Nakahara (Thysanoptera: Thripidae) and associated natural enemies on avocado (Persea americana Miller)

Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.     

Phylogeny of cardinalfishes (Teleostei: Gobiiformes: Apogonidae) and the evolution of visceral bioluminescence

The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.     

Biological control of three floating water weeds,<Emphasis Type="Italic">Eichhornia crassipes,Pistia stratiotes</Emphasis>, and <Emphasis Type="Italic">Salviniamolesta</Emphasis> in the Republic of Congo

Since 1999, four specific weevils (Coleoptera, Curculionidae) were released in the Republic of Congo against three exotic floating water weeds: Neochetina eichhorniae Warner and N. bruchi Hustache against water hyacinth, Neohydronomus affinis Hustache against water lettuce, and Cyrtobagous salviniae Calder and Sands against water fern. Recoveries of exotic weevils were made from all 24 release sites except one, and all four species have established and spread (up to 800 km for water hyacinth weevils). Within a few years of releases, control of water fern and water lettuce was such that fishing and navigation could be resumed, while reductions of water hyacinth populations were only beginning.     

A molecular phylogeny of Hebeloma species from Europe

In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.     

Taxonomic status of the species of the green algal genusNeochloris

Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.     

Die GattungKarschia — Bindeglied zwischen bitunicaten Ascomyceten und lecanoralen Flechtenpilzen?

The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.

     

Demographic characteristics of an intertidal bay goby (Lepidogobius lepidus)

Synopsis In a fourteen month study (May 1976 – June 1977) I examined the following characteristics of an intertidal bay goby (Lepidogobius lepidus) in Morro Bay, California, U.S.A.: annual and seasonal patterns of abundance, age composition and growth rates, survivorship and mortality patterns, and the reproductive cycle for female gobies. Fishes were collected with the aid of quinaldine and otoliths and ovaries removed. Age and growth rates were estimated from otolith annuli using a back calculation formula and a Brody-Bertalanffy growth curve. Mortality rates were derived using the methods of Heincke (1913), Robson & Chapman (1960), mean age, and a catch curve (Ricker 1975). A gonad index was used to describe the annual reproductive cycle. Results indicated that abundance fluctuated seasonally and that these fluctuations appeared to be caused by reproductive emigrations. Bay gobies reached an age of 7+ and a standard length of 87 mm. Growth was relatively constant (6 mm yr⁻¹) until age 5, at which point it began to decline. The mean rates of survivorship, mortality, and instantaneous mortality were 0.75, 0.25, and 0.29 respectively. Mortality rates for individual age classes ranged from 0.13 to 0.51 and increased with age. This stock appears to reproduce mainly during the winter.     

Systematic significance of mature embryo of bamboos

The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.