兰花蕉属植物染色体新计数

首次报道了国产兰花蕉属植物2种1变种的体细胞染色体计数,其中兰花蕉及其变种长萼兰花蕉为2n=54,为六倍体;海南兰花蕉为2n=18,为二倍体。分析了世界范围内兰花蕉属植物染色体数及其倍性的地理学关系。     

长毛红山茶和长尾红山茶的核型分析

<正> 长毛红山茶(Camelliav uillosa Chang et S.Y.Liang)和长尾红山茶(C.longicaudata Chang et S.Y.Liang)均为张宏达教授定的新种,分别隶属于山茶属(Camellia)红山茶组(Sect.Camellia)的滇山茶亚组(Subsect.Reficulala)和光果红山茶亚组(Subsect.Lucidissima),前者分布在我国的湖南、广西和贵州,后者分布在广东和广西。 红山茶组共有33个种、1个亚种,7个变种。根据文献资料统计,该组作过染色体计数的有10个种,1个亚种和6个变种,作过核型分析的有4个种、1个亚种和2个变种。本文对该组的长毛红山茶和长尾红山茶的核型作首次报道,并与该组的10个种,1个亚种和6个变种的染色体数目或核型作了比较。     

中国葛属（Pueraria DC．）的研究

本文对国产葛属植物９种２变种进行了全面整理．对其中的主要类群进行了深入的研究．通过野外考察,腊叶标本的研究和细胞染色体的计数．使对中国葛属植物有一个较为全面的了解。     

紫堇属3种1变种的染色体数目

紫堇属Corydalis Vent.全世界约有300多种,我国约有230种。据文献报道,本属做过染色体计数的约30种以上。本文报道了我国产3种1变种的染色体数目。其中除延胡索C. yanhusuo W. T. Wang ex Z. Y. Su et C. Y. Wu曾有过2n=28的报道外,其余均为首C次报道。     

国产姜科植物的染色体计数(四)

<正> 本文继续报道对国产姜科植物8属15种所作的染色体计数观察的结果,其中9种是染色体计数的新记录(表1、图1),并初步确定茴香砂仁属Achasma和喙花姜属Rhynchanthus的染色体基数分别为12和11。     

中国柴胡属染色体数目和核型研究

采用植物染色体常规压片技术,报道了中国柴胡属(Bupleurum L .)13种5变种24个居群的染色体数目,其中4种5变种为首次报道,同时报道了5种1变种的细胞核型.除天山柴胡两个居群、紫花鸭跖柴胡一个居群和北柴胡一个居群是多倍体外,其它均为二倍体.主要结论如下:(1)秦岭柴胡和细茎有柄柴胡处理为独立的种更为合适;紫花阔叶柴胡作为大叶柴胡变种的处理是合理的;黄花鸭跖柴胡处理为紫花鸭跖柴胡的变种是不合理的.(2)紫花鸭跖柴胡和北柴胡可能都是还没有被完全认识的复合类群,需要进一步研究.(3)x=7可能是柴胡属的原始基数.     

中国悬钩子属空心莓组与木莓组28种和变种的核型比较研究

为了给悬钩子属Rubus植物的分类、系统演化和开发利用积累细胞学证据,对悬钩子属空心莓组sect.Idaeobatus 18个种(变种)和木莓组10个种(变种)的染色体数目和核型进行了比较研究,其中10个种(变种)的染色体数目和26个种(变种)的核型以及该属植物存在混倍体类型为首次报道.研究结果表明,研究的空心莓组和木莓组sect.Malachobatus植物染色体均小形,绝对长度均在3 μm以下,染色体由中部着丝点染色体(约90%)和近中部着丝点染色体构成,核型分类主要属于"1A"型(85%以上),说明这两组植物在整个系统演化中处于相对原始的地位.本研究中的28个种(变种)均为整倍体,未发现有非整倍体类型.但是两个组的染色体数目和核型结构有较大差异.在空心莓组的18种植物中,除拟复盆子R.idaeopsis为2n=3x=21、茅莓R.parvifolius为2n=2x=14与2n=4x=28的混倍体外,其余种染色体数目和类型均为2n=2x=14.而在木莓组的10个种中,除寒莓R.buergeri为2n=8x=56外,其余种的染色体数目和倍性均为2n=4x=28.此外,本研究所涉及的空心莓组11个亚组中的7个亚组的18个种(变种),亚组内的物种间染色体核型构成差异明显,有些甚至超过了亚组间一些物种的差异;而涉及的木莓组13个亚组的6个亚组10个种(变种),亚组间物种染色体核型结构差异较明显,但亚组内物种间染色体核型结构差异较小.本文依据细胞学资料对这两组植物的系统演化和一些种的分类进行了讨论.     

国产姜科植物的染色体计数(2)

<正> 本文继续对国产姜科植物7属,14种和1栽培种作了染色体计数观察,其中9种和1栽培种是染色体计数的新纪录(表1,图1)。通过对大豆蔻Hornstedtia hainanensis的细胞学观察,初步确定大豆蔻属Hornstedtia的染色体基数为12(X=12)。     

杜鹃花属马银花亚属一些种类染色体数目报道

对杜鹃花属马银花亚属中的马银花组和长蕊杜鹃组7种1变种的染色体数目进行了观察,其中6种1变种的染色体数目为首次报道,仅薄叶马银花（Rhododendron leptothrim Balf. f. ＆ Forrest）的染色体数目以前有过报道。细胞学研究结果表明,马银花亚属所观察种类的染色体数目相同,均为2n=26。     

国产姜科植物的染色体计数(6)

<正> 本文继续对5属14种姜科植物作染色体计数观察,其中8种是染色体计数的新记录(表1,图版Ⅰ)。通过对偏穗姜(Plagiostachys austrosinensis T. L.Wu & Senjen)的根尖染色体观察,初步确定偏穗姜属(Plagiostachys)的染色体基数为12,并首次报道了阳荷(Zingiber striolatum Diels)的核型。     

Aspects of maturation and reproduction in hexanchiform and squaliform sharks

Three species of hexanchiform sharks belonging to two families and 12 species of squaliform sharks belonging to three families were recorded in fish landing site surveys in eastern Indonesia. Of these, the Squalidae were the most abundant species landed, with Squalus hemipinnis, Squalus edmundsi and Squalus montalbani contributing 0·4, 0·4 and 0·5% to the total number of sharks recorded in a 5 year survey of Indonesian fish landing sites. In comparison, the hexanchid Hexanchus griseus contributed the largest percentage to the total shark biomass. For many species, the majority of the catch consisted of immature fishes, which had not yet been able to reproduce. The data presented in this article are the first biological data reported on most of these shark species and are thus vital for fisheries managers and conservation assessors.     

Ascomycetous yeast species recovered from grapes damaged by honeydew and sour rot

Aims: To identify ascomycetous yeasts recovered from sound and damaged grapes by the presence of honeydew or sour rot. Methods and Results: In sound grapes, the mean yeast counts ranged from 3·20 ± 1·04 log CFU g^?1 to 5·87 ± 0·64 log CFU g^?1. In honeydew grapes, the mean counts ranged from 3·88 ± 0·80 log CFU g^?1 to 6·64 ± 0·77 log CFU g^?1. In sour rot grapes counts varied between 6·34 ± 1·03 and 7·68 ± 0·38 logCFU g^?1. Hanseniaspora uvarum was the most frequent species from sound samples. In both types of damage, the most frequent species were Candida vanderwaltii, H. uvarum and Zygoascus hellenicus. The latter species was recovered in high frequency because of the utilization of the selective medium DBDM (Dekkera/Brettanomyces differential medium). The scarce isolation frequency of the wine spoilage species Zygosaccharomyces bailii (in sour rotten grapes) and Zygosaccharomyces bisporus (in honeydew affected grapes) could only be demonstrated by the use of the selective medium ZDM (Zygosaccharomyces differential medium). Conclusions: The isolation of several species only from damaged grapes indicates that damage constituted the main factor determining yeast diversity. The utilization of selective media is required for eliciting the recovery of potentially wine spoilage species. Significance and Impact of the Study: The impact of damaged grapes in the yeast ecology of grapes has been underestimated.     

山东地区药用植物染色体数目的观察(Ⅲ)

本文对17科35种药用植物体细胞染色体作了计数,并就有关的细胞学和分类学问题略作了讨论。     

A new pollen type,C-banded and fluorochrome counterstained chromosomes,and evolution inGuatteria and related genera (Annonaceae)

Guatteria, Guatteriopsis, Guatteriella andHeteropetalum share the same conspicuous pollen type which is new for theSpermatophyta. It is zonoaperturate with a folded aperture region and an extremely reduced exine. First chromosome counts and karyotype analyses forGuatteriopsis (4 species investigated) andGuatteriella (1 species) are identical with those ofGuatteria (19 species seen): 2n = 28. The genome is characterized by diploidization and partly telocentric chromosomes. Sequentially Giemsa C- and fluorochrome banded chromosomes and interphase nuclei are described. The cuticular folding pattern is distinct forHeteropetalum only. Growth forms and ecology are reported for many species. The evolutionary pattern of theGuatteria group is discussed and compared with other genera and families.     

First nuclear DNA C-values for 28 angiosperm genera

This paper reports first DNA C-values for 28 angiosperm genera. These include first DNA C-values for 25 families, of which 16 are monocots. Overall familial representation is 47.2 % for angiosperms, but is now much higher for monocots (75 %) and basal angiosperms (73.1 %) than for eudicots (38.7 %). Chromosome counts are reported for 22 taxa, including first records for six genera plus seven species. Unrepresented families will become increasingly enriched for monotypic taxa from obscure locations that are harder to access. Thus, completing familial representation for genome size for angiosperms may prove impossible in any short period, and progress towards this goal will become slower.     

上海地区若干种栽培植物的染色体数目

本文报道了上海地区栽培的11属12种植物的染色体数目,并就有关的细胞学和分类学问题略作了讨论。凭证标本藏于复旦大学生物系植物标本室。     

Colonization of the deep sea by fishes

Analysis of maximum depth of occurrence of 11 952 marine fish species shows a global decrease in species number (N) with depth (x; m): log₁₀N = ?0·000422x + 3·610000 (r² = 0·948). The rate of decrease is close to global estimates for change in pelagic and benthic biomass with depth (?0·000430), indicating that species richness of fishes may be limited by food energy availability in the deep sea. The slopes for the Classes Myxini (?0·000488) and Actinopterygii (?0·000413) follow this trend but Chondrichthyes decrease more rapidly (?0·000731) implying deficiency in ability to colonize the deep sea. Maximum depths attained are 2743, 4156 and 8370 m for Myxini, Chondrichthyes and Actinopterygii, respectively. Endemic species occur in abundance at 7–7800 m depth in hadal trenches but appear to be absent from the deepest parts of the oceans, >9000 m deep. There have been six global oceanic anoxic events (OAE) since the origin of the major fish taxa in the Devonian c. 400 million years ago (mya ). Colonization of the deep sea has taken place largely since the most recent OAE in the Cretaceous 94 mya when the Atlantic Ocean opened up. Patterns of global oceanic circulation oxygenating the deep ocean basins became established coinciding with a period of teleost diversification and appearance of the Acanthopterygii. Within the Actinopterygii, there is a trend for greater invasion of the deep sea by the lower taxa in accordance with the Andriashev paradigm. Here, 31 deep‐sea families of Actinopterygii were identified with mean maximum depth >1000 m and with >10 species. Those with most of their constituent species living shallower than 1000 m are proposed as invasive, with extinctions in the deep being continuously balanced by export of species from shallow seas. Specialized families with most species deeper than 1000 m are termed deep‐sea endemics in this study; these appear to persist in the deep by virtue of global distribution enabling recovery from regional extinctions. Deep‐sea invasive families such as Ophidiidae and Liparidae make the greatest contribution to fish fauna at depths >6000 m.     

CHROMOSOME STUDIES IN THE ALPINE AND SUBALPINE FLORAS OF MEXICO AND GUATEMALA

Beaman , J. H. (Michigan State U., East Lansing), D. C. D. De Jong , and W. P. Stoutamire . Chromosome studies in the alpine and subalpine floras of Mexico and Guatemala. Amer. Jour. Bot. 49(1): 41–50. Illus. 1962.—Chromosome counts of 101 collections representing 69 species in 42 genera and 22 families have been obtained. Counts are reported for the first time in 59 species and 2 genera (Oreobroma and Villadia). Counts establishing new basic numbers were found in Draba, Lithospermum, and possibly in Arenaria. Where pertinent, the chromosomal data are related to previous taxonomic or chromosomal investigations. Chromosome numbers are now known in nearly half of the species in the alpine flora of Mexico.     

CHROMOSOME NUMBERS IN COMPOSITAE VIII: HELIANTHEAE

One hundred and ninety-three new counts are reported for the tribe Heliantheae of Compositae, mostly based on determinations of meiotic material, including first counts for the genera Adenothamnus, Chrysogonum, Enceliopsis, Guardiola, Isocarpha, Lipochaeta, Otopappus, and Oyedaea, as well as first counts for 66 species. The original counts are discussed in relation to those previously reported for the tribe, by genera and subtribe. Two-thirds of the approximately 150 genera and more than a third of the roughly 1500 species have now been examined. The incomplete knowledge of generic relationships in the tribe often make the interpretation of these chromosome numbers difficult. Three observations are documented and discussed: (1) genera with low chromosome numbers are few; (2) genera with aneuploid series are abundant; and (3) the original basic chromosome number in the tribe is probably in the range of x = 8 to x = 12.     

Counts of coral reef fishes by an experienced observer are not biased by the number of target species

Fishes are commercially, recreationally and functionally important inhabitants of coral reefs. Accordingly, accurate assessments of fish abundance and diversity are necessary for effective reef management. While some reef fish monitoring programmes target all fishes, many survey a subset of common and visually obvious species. Changing to counts of all species, while desirable, risks new and unwelcome biases from altered observer swimming speeds and search patterns. Here we test whether substantially increasing the number of target species in an established fish monitoring programme biases counts of the original subset, so precluding ongoing comparisons with historical data. A subset of 141 fish species have been visually surveyed along 50 × 5 m transects over 27 years throughout Australia's Great Barrier Reef. We experimentally compared counts of the subset from standard subset-only surveys and from surveys of all species (excluding small site-attached fishes that are surveyed separately) at three diverse reefs. Subset species richness and abundance, in total and of major families, and assemblage structure did not differ due to survey method. The high-level experience of the one observer appeared to overcome new biases from counting more species and the extra 2 min/transect was not logistically excessive. Surveys of all fishes recorded almost 80% more species than subset-only surveys and >130% higher total abundance on average from >150% more genera that included abundant and functionally important taxa. Overall, fish counts by an experienced observer were not biased by the number of species surveyed and counts of all species markedly improved assessments of reef fish diversity and function.