四种独花报春属植物种子萌发特性初探

独花报春属植物主要分布于喜马拉雅东段、缅甸北部至我国云南、四川西部,分布区狭窄,种群数量少,接近濒危.通过对独花报春属四个种种子萌发特性的研究表明:独花报春种子大小存在一定差异,不同种的萌发率存在显著的差异,光照是独花报春种子萌发的必须条件.     

贵州种子植物新分布

对采自梵净山国家级自然保护区的植物标本鉴定和查阅相关资料,发现了贵州十字花科一新分布属:山萮菜属(Eutrema R Br.),4个贵州新分布种:山萮菜(Eutrema yunnanerse Franch.),长伞梗英迷(Viburnum longiradiatum Hsu et S.W.Fan),莸(叉枝莸)(Caryopteris divaricata Maxim.),巴东木莲(Manglietia patungensis Hu).     

贵州蕨类植物新记录——长根假冷蕨和膜叶冷蕨

报道2种贵州蕨类植物新纪录:长根假冷蕨Pseudocystopteris repens Ching和膜叶冷蕨Cystopteris pellucida(Franch.) Ching.     

佛教在贵州的传播与茶叶生产的发展及饮茶

正佛教自唐代起传入贵州。唐贞观13年(公元630年),由候弘仁将佛教传入贵州。思州地界的梵净山是西南佛重点之一,与四川峨眉山、云南鸡足山齐名,在它周围纷纷建立道场(《梵净山佛教苑》P:61,龙云清松桃县政协《梵净山纪略》)。另据《太平广记》引唐·牛肃《记闻》云:"唐中腾,字思远,唐时散大夫郏城令,弃官从奴,精心释教,从其志终     

贵州梵净山自然保护区悬钩子属植物资源考察及开发利用

对贵州梵净山自然保护中心的蔷薇科悬钩子属植物的野生种的分布、生长习性等现状进行了调查,共采集到31种2变种,其中梵净山悬钩子为梵净山特有种;绵果悬钩子、五叶鸡爪茶、无刺掌叶悬钩子为梵净山的新记录种;三花悬钩子、山莓、宜昌悬钩子、尾叶悬钩子分布最为广泛;绵果悬钩子、红腺悬钩子、宜昌悬钩子、尾叶悬钩子具有很高的利用价值和开发前景,并就该保护区悬钩子植物的开发利用潜力进行评价。     

贵州省堇菜属植物分布新纪录

报道贵州堇菜属植物分布新纪录1种,即紫背堇菜(Viola violacea),调查发现堇菜属3种植物在贵州有新分布,即庐山堇菜(Viola stewardiana)、如意草(Viola arcuata)、球果堇菜(Viola collina),并且修订了纤茎堇菜(Viola tenuissima)以前错误使用情况。     

贵州省淫羊藿属(小檗科)特有和珍稀植物及其保护价值

报道贵州省小檗科淫羊藿属特有植物(或已知仅贵州分布植物)10种1变种,分别为黔北淫羊藿(E.borealiguizhouenseS.Z.He & Y.K.Yang)、短茎淫羊藿(E.brachyrrhizum Steam)、德务淫羊藿(E dewuense S.Z.He,Probst & W.F.xu)、普定淫羊藿(E.pudingense S.Z.He,Y.Y.Wang & B.L.Guo)、多花淫羊藿(E.multiflorum T.S.Ying)、剑河淫羊藿(E.myrianthum Steam var.jianheense S.Z.He & B.L.Guo)、小叶淫羊藿(E.parvifolium S.Z.He & T.L.Zhang)、拟巫山淫羊藿(E.pseudowushanense B.L.Guo)、贵州淫羊藿[E.sagittatum (Siebold & Zuccarini)Maximowicz var.guizhouense S.Z.He & B.L.Guo]、水城淫羊藿(E.shuichengense S.Z.He)和单叶淫羊藿(E.simplicifolium T.S.Ying);易危植物2种,分别为小叶淫羊藿和单叶淫羊藿,被《中国物种红色名录》收录.描述了贵州淫羊藿属特有植物和珍稀植物的药用和保护价值及其分布产地.对淫羊藿属存在的问题进行总结分析,并提供贵州省小檗科淫羊藿属植物新名录和以贵州标本命名的淫羊藿属新物种名录.     

贵州蕨类植物新资料

报道了在贵州西部新发现的5种蕨类植物纪录种:即峨眉瘤足蕨(Plagiogyri aassurgens Christ)、姬蹄盖蕨(Athyrium subrigenscens(Hayata)Hayata ex H.Ito)、喜马拉雅蹄盖蕨(A.foliolosum Moore ex Sim.)、滇南蹄盖蕨(A.austroyunnanense Ching)和假边果鳞毛蕨(Dryopteris caroli-hopei Fraser-Jenkins),其中姬蹄盖蕨[Athyrium.subrigenscens(Hayata)Hayata ex H.Ito]为中国大陆新分布。新纪录凭证标本保存于毕节学院植物标本室。     

濒危植物梵净山冷杉的种子育苗试验研究

梵净山冷杉为国家一级保护的濒危植物.本研究以2014年秋季采收的梵净山冷杉种子为材料,于2014和2015年采用不同方法进行育苗试验,研究了梵净山冷杉种子繁育技术.结果表明,梵净山冷杉的出苗时间为3月初至4月下旬.不同播种时间、不同基质和不同遮阳方式的梵净山冷杉出苗时间、出苗率和苗木保存率不同.当年播种的出苗时间在3月初较第2年播种的提前1个月出苗;以黔中山地黄壤+松林腐殖土为基质出苗数量和苗木保存率为最高;3-10月搭建遮阳网比不遮阳苗木保存率高.     

贵州兰科植物新分布记录(Ⅲ)

贵州省兰科(Orchidaceae)植物分布新纪录5种,即斑叶杓兰(Cypripedium margaritaceum Franch),红头金石斛(Flickingeria calocephalaZ.H.Tsi et S.C.Chen),二耳沼兰(Crepidium biaurita(Lindl.) Kuntze),条叶舌唇兰(Platanthera leptocaulon (Hook.f.)Soo),文山兜兰(Paphiopedilum wenshanense Z.J.Liu et J.Y.Zhang).     

The U.S.-Canada Free Trade Agreement and Commodity Transportation Services among U.S. States

The Free Trade Agreement (FTA) implemented beginning in 1989 by the United States aid Canada will have significant impacts on bilateral trading patterns. In addition to its long-term, investment-related repercussions, the FTA will affect the volume, commodity composition, and spatial distribution of trade and, consequently, the transportation services required to move commodities between the two nations. This paper examines the changing spatial structure of U.S.-Canadian trade under the FTA. It employs commodity-specific analyses of tariffs and non-tariff barriers, as well as price and income elasticities of demand, to estimate sectoral and special changes among U.S. states in total, land, water, and airborne commodity flows since 1988 attributable to the FTA. The analysis details the assumptions and methodology used, elaborates upon the likely consequences for me nation's ten largest customs districts, particularly New York, and concludes with some comments on other forces that may alter the expected results.     

U.S. Economic Growth vs. Environmental Conditions

A widely-held belief is that stricter environmental regulations stifle economic growth. To determine empirically the effect of environmental conditions and policies on state-level per capita income growth, a Barro-type economic growth model was estimated for the years 1982 to 1991, which correspond to two consecutive troughs in the business cycle. States with better environmental conditions had significantly higher income growth rates during this period. At the same time, stricter environmental policies did not significantly depress income growth. Data used include recently developed, consistent measures of environmental policy and quality for individual states, as well as data from the 1980 U.S. Census and Bureau of Economic Analysis.     

The breeding of the cultivated potato species solanum x juzepczukii and S. x curtilobum II. The resynthesis of S. x juzepczukii and S. x curtilobum

Summary The possibility of combining anew the genomes of wild and cultivated progenitors of triploid S. x juzepczukii and pentaploid S. x curtilobum by following the known evolutionary pathway of these species was investigated.The resynthesis of S. x juzepczukii was easy, and a wide range of synthetic forms was bred. Among these were forms with higher frost resistance (-5°C) than has been found in natural S. x juzepczukii. The total tuber glycoalkaloid content of several synthetic hybrids was lower than or as low as that of natural clones. Most synthetic hybrids were more vigorous than natural S. x juzepczukii and produced about the same types of tubers as are found in the natural range of variation. The best diploid parents were found in the species S. goniocalyx.The attempt to resynthesize pentaploid S. x curtilobum has not been successful but tetraploid plants were obtained in the process. An explanation for the occurrence of tetraploids resulting from triploid x tetraploid and/or diploid crosses is offered.The newly bred tetraploids contain at least one genome from S. acaule (possibly two) and hybridize easily with ssp. andigena. They thus provide a means for the transfer of S. acaule germ plasm into the tetraploid cultivated gene pool which would profit from the frost resistance of S. acaule.     

Main gene centres of cultivated plants and their wild relatives within the territory of the U.S.S.R.

An account is given of the specific and varietal diversity of the chief indigenous cultivated plants of the U.S.S.R. and their wild relatives. The author also mentions the economic value of this initial material and describes some of the principal achievements of plant breeders in recent times. The genera dealt with are as follows: Triticum, Secale, Hordeum, Helianthus, Linum, Malus, Pyrus, Cydonia, Mespilus, Prunus, Armeniaca, Amygdalus, Cerasus, Microcerasus, Ribes, Cornus, Vitis, Juglans, Pistacia, Corylus, Cucumis, and Medicago.Prepared as a contribution to the symposium on Origin and Evolution of Cultivated Plants, at the Tenth International Botanical Congress, 1964. Submitted by J. B. Hutchinson and J. G. Hawkes.     

U.S. Farm Wages and Labor Market Efficiency

This study examines convergence in real wages for hired farm labor in the U.S. agricultural sector over the period 1978‐92,using the ‘average farm’ in each county as an observation. Convergence is investigated at the aggregate (or the entire U.S. level)and regional levels. Evidence supports convergence with a slower rate at the aggregate level than that at the regional level. Suggested by the evidence is the possibility that absolute benefits of wage equalization across states are ‘contagious’—that one state's successful investment raises productivity and factor payments in neighboring states and that agricultural labor markets are efficient and integrated all over the country.     

苏丹草高梁及其杂种的细胞遗传学研究

苏丹草(S. sudanense)与高粱(S.bicolor)均为禾本科高梁属植物,两者的杂种优势明显,杂交种品质好,抗逆性强,在水产、畜禽养殖及资源利用与环境保护上有着广阔的开发利用前景,但两者是否属于同一个种至今存在争议.本文采用去壁低渗.火焰干燥法,分析了2份苏丹草、2份高粱及其3个杂种F1有丝分裂核型,观察了3个杂种F1减数分裂染色体行为和2个杂种F2体细胞染色体数目.结果表明,苏丹草、高粱及其杂种F1均为1A核型,但核型公式不完全相同,苏丹草Sa为2n=18m+2sm(sat),高粱3042A和3042A×Sa F1为2n=20m,其余材料均为2n=20m(sat).苏丹草、高粱及其杂种F1 3者在10条染色体的绝对长臂、绝对短臂、绝对全长、臂比和相对全长上差异均不显著(P0.05),说明苏丹草与高粱在染色体长度上的变化不明显.杂种F1花粉母细胞减数分裂,终变期和中期Ⅰ染色体核型和数目清晰可见(2n=2x=20),配对行为规则;棒状和环状二价体的频率因组合不同而异,Tx623A×S722 F1、3042A×Sa F1和Tx623A×Sa F1棒状二价体频率分别为4.887、5.710和5.126,环状二价体频率分别为5.113、4.290和4.874;在后期Ⅰ,配对的染色体能够正常分离.杂种F2体细胞染色体数目为20(2n=20).因此,苏丹草与高粱的亲缘关系非常近.