竹柏中两个新二萜双内酯

从竹柏[Podocarpus nagi(Thunb.)Zoll. et Mor. ex Zoll.]种子中分离到两种新化合物:表赛络文C(1)和竹柏内酯甙B(2),并用波谱及化学方法鉴定了其结构。化合物1显示较强的细胞毒性,化合物2则无活性。     

黄棉木中两个新的三萜类化合物

从黄棉木（Metadina trichotoma（Zoll．et．Mor．）Bakn．）树皮中分离得到2个新的三萜类化合物：3-oxo-29-hydroxy-urs-12-en-27,28-dioicacid（黄棉木素A,1）和3-oxo-21β-hydroxy-urs-12-en-27,28-dioicacid（黄棉木素B,2）。其结构主要通过MS,1D以及2DNMR等波谱方法鉴定。     

The Chemical Constituents from Podocarpus nagi (II)

Continuing the former report, four more constituents Were isolated from the seeds of Podocarpus nagi (Thunb.) Zoll. et Mor. ex Zoll. (Podocarpaceae). They were identified as sciadopitysin (Ⅰ), amentoflavone-4', 4"', 7, 7"-tetramethyl ether (Ⅱ), nagilactone C(Ⅲ) and ethyl-β-D-pyranoglucoside (Ⅳ). Ⅰ, Ⅱ and Ⅳ were first reported in this plant. Ⅲ shows stronge cytotoxic activity.     

Lijndenia, a re–established paleotropical genus of the Melastomataceae–Memecyleae

The genus Lijndenia Zoll. & Mor. is re–established and emended to include four species, L. laurina Zoll. & Mor. from W Malesia and Java, L. capitellata (Arn.) Bremer from Ceylon, L. gardneri (Thw.) Bremer from Ceylon, and L. barteri (Hook. f.) Bremer from tropical W Africa. The latter three names are new combinations.     

裸子植物上的三个小煤炱科新种

本文报道寄生在裸子植物上的三个小煤炱科新种。它们是(1)杉科上的杉木附丝壳Appendiculella cunninghamiae Y.X.Hu et B.Song,杉科是小煤炱科寄主的世界新记录;(2)罗汉松科上的竹柏生小煤炱Meliola podocarpicola Y.X.Hu et B.Song;(3)买麻藤科上的买麻藤生小煤炱Meliola gneticola Y.X.Hu。其形态特征有拉丁文和汉文描述,并附有形态图。模式标本存放在广东省微生物研究所。     

天线蛋白和类囊体膜脂对光合系统紫黄质循环的调节作用研究进展

紫黄质循环是紫黄质(V)经过中间物单环氧玉米黄质(A)形成玉米黄质(Z)的可逆转换,是光合系统聚光复合体在低光下的聚光状态与高光下的能量耗散状态之间的转换开关.叶黄素中的玉米黄质可钝化(去激发)激发三线态叶绿素(3Chl*)和激发单线态氧(1O2*),紫黄质循环可直接或间接地通过非光化学淬灭(NPQ)耗散PSⅡ天线蛋白中的过量光能.天线蛋白被认为是依赖玉米黄质(Z)耗散过量光能的部位,天线蛋白通过结合紫黄质循环组分(V,A和Z)来调节紫黄质循环.类囊体膜脂的性质和结构影响紫黄质循环组分(V,A和Z)间的转换,V的脱环氧化速率依赖于V在类囊体膜脂上侧向扩散的速率,紫黄质脱环氧化作用第一步(由V到A的转换)的速度常数是第二步(由A到Z的转换)速度常数的4～6倍.现有的结果表明,天线蛋白和类囊体膜脂是紫黄质循环最基本的调节器.该文对近年来国内外关于紫黄质循环的基本反应及其功能、紫黄质循环酶结构性质和辅因子以及天线蛋白和类囊体膜脂对紫黄质循环的调节作用及其机理等方面的研究进展进行了综述.     

囊萼花属─—中国玄参科新记录属及—新种

报道了我国玄参科的一个新记录属──囊萼花属ＣｙｒｔａｎｄｒｏｍｏｅａＺｏｌｌ，该属为印度－马来西亚分布，它经过泰国北部，缅甸与我国发生连系，到达我国云南贡山、屏边、金平。全世界有１１—１２种，我国（云南）首次记录两种，其中一种为新种。     

罗汉松根瘤内生细菌的分离和特性

罗汉松Ｐｏｄｏｃａｒｐｕｓｍａｃｒｏｐｈｙｌｌｕｓ(Ｔｈｕｎｂ .)Ｄ .Ｄｏｎ是裸子植物亚门罗汉松科一种 ,在我国主产长江以南各省 ,为用材及园林绿化的优良树种 ,种子和根可入药。关于罗汉松根际微生物的研究 ,梁秀棠[1] 、花晓梅[2 ] 曾报道其根与菌根真菌共生形成外生或内生菌根。国外有学者发现 ,几种其它的罗汉松科植物Ｐ .ｎｕｂｉｇｅｎｕｓ等具有结瘤固氮现象[3～ 6] ,但对其与细菌共生形成根瘤以及根瘤内生细菌的分离鉴定至今国内外尚未见报道。作者在广西的南宁、桂林、扶绥及广东的佛山等地进行野外调查 ,证明罗汉松在自然界…     

安徽省楼梯草属新记录

报道了产于安徽省楼梯草属2新记录种,分别为锐齿楼梯草(Elatostema cyrtandrifolium)、深绿楼梯草(Elatostema atroviride).     

Foliar sclereids in Memecylon and Lijndenia (Melastomataceae) from Borneo, Java, Malaya and Sumatra

Foliar sclereids are investigated in 41 Memecylon species and in Lijndenia laurina Zoll. & Mor. (= Memecylon oligoneurum Bl.). The predominance of filiform sclereids in the Memecylon species is remarkable. Lijndenia laurina has ramiform sclereids.     

中国楼梯草属(荨麻科)植物省级分布新记录

报道荨麻科楼梯草属7种1变种植物在我国6个省区分布的新记录,其中广西分布新记录的有算盘楼梯草和多歧楼梯草,贵州分布新记录的有曲毛楼梯草,海南分布新记录的有锐齿楼梯草和深绿楼梯草,湖南分布新记录的有短毛楼梯草,四川分布新记录的有丝梗楼梯草,云南分布新记录的有细角楼梯草。     

Floral Development of Three Maesa Species, with Special Emphasis on the Position of the Genus within Primulales

Floral development of three Maesa Forssk. species, M. argenteaWall., M. japonica(Thunb.) Moritzi ex Zoll. and M. perlarius(Lour.)Merr., was studied with a scanning electron microscope. Thedistinctive floral features of the genus, such as presence oftwo persistent bracteoles, perigynous flowers and many-seededfruits, have been used to discuss the systematic position ofthe genus within Primulales. In addition, the development ofcommon stamen-petal primordia, the number, arrangement and positionof ovules and the shape of the anthers provide evidence in favourof placing Maesa in a separate family, Maesaceae, as suggestedby Anderberg and Ståhl (Canadian Journal of Botany, 73:1699–1730, 1995). Copyright 2000 Annals of Botany Company Primulales, Maesa argentea Wall., Maesa japonica(Thunb.) Moritzi ex Zoll., Maesa perlarius(Lour.) Merr., floral ontogeny, SEM     

Some gasteromycetes from Northern Thailand

11 species of gasteromycetes are recorded from Thailand. 8 are new to the area, viz. Arcangeliella rosea (Harkn.) Zeller & Dodge, Cyathus berkeleyanus (Tul.) Lloyd, Hymenogaster cf. abellus Massee & Rodw., Morganella compacta (Cunn.) Kreisel & Dring, Mutinus bambusinus (Zoll.) Fischer, Nidula niveo–tomentosa (Henn.) Lloyd, Phallus rubicundus (Bosc) Fr., Scleroderma sinnamariense Mont. Further a compiled check–list of the gasteromycetes known from Thailand is provided.     

江津楼梯草, 重庆荨麻科一新种

描述了自重庆南部发现的荨麻科楼梯草一新种,江津楼梯草(Elatostema jiangjinense)。此新种与锐齿楼梯草(E. cyrtandrifolium)近缘,两者的区别在于江津楼梯草的叶在狭侧具2条二级脉,托叶卵形或披针形,以及雄总苞片在顶端具长角状突起。     

中国12省荨麻科植物分布新记录

报道荨麻科16种植物在中国12个省(区)分布的新记录,其中河南省和福建省分布新记录种有粗齿冷水花(Pilea sinofasciata),陕西省和安徽省分布新记录种有假楼梯草(Lecanthus peduncularis),甘肃省分布新记录种有糯米团(Gonostegia hirta)和假楼梯草,青海省分布新记录种有亚高山冷水花(Pilea racemosa),广东省分布新记录种有隆脉冷水花(P.lomatogramma),海南省分布新记录种有锐齿楼梯草(Elatostema cyrtandrifolium),广西壮族自治区分布新记录种有西畴楼梯草(E.xichouense),贵州省分布新记录种有隐脉楼梯草(E.obscurinerve)和红花冷水花(Pilea rubriflora),云南省分布新记录的种有星序楼梯草(Elatostema asterocephalum)、深绿楼梯草(E.at-roviride)、褐脉楼梯草(E.brunneinerve)、多枝楼梯草(E.ramosum)、翅茎赤车(Pellionia caulialata)和光果赤车(P.leiocarpa),西藏自治区分布新记录种有念珠冷水花(Pilea monilifera).     

稻属植物胚的形态结构与二（异）型子叶

长久以来植物学界认定稻 (OryzasativaL .)是单子叶植物。作者从稻胚发育的研究中确认稻胚具二型子叶 ,并非单子叶。稻属其他种的胚胎形态与O .sativa是否相同 ?是否具二型子叶 ?根据扫描电子显微镜的观察结果 ,稻属 (Oryza) 2 2个种和亚种的胚的形态结构可以分为两种类型。O .sativa等 16个种胚具腹鳞和侧鳞 ,属第一类型 ;O .meyeriana (Zoll.etMor.exSteud .)Baill.ssp .tuberculataW .C .WuetY .G .Lu ,G .C .Wang等 6个种 (亚种 )胚缺腹鳞和侧鳞 ,属第二类型。O .sativa和O .meyerianassp .tuberculata的胚胎发育过程所出现的盾片原基、胚根鞘原基、胚芽鞘原基和生长锥均来自原胚 ,前二者发育成胚套 ,是外围子叶 ;胚芽鞘原基发育成围在生长锥外并盖住生长锥的空心的倒锥状胚芽鞘 ,是顶生子叶。第一类型与第二类型稻胚都具有二型子叶。第二类型稻胚在盾片原基发育过程中并不分化出腹鳞和侧鳞 ,因而造成第二类型稻胚缺腹鳞与侧鳞。稻的二型子叶源于原胚的背腹极性分化     

云南地方稻种持久抗瘟性的研究

1996～1999年,在不同纬度、不同海拔和不同稻作生态类型的重病区设立5个持久抗性稻瘟病鉴定圃.试验材料为云南的74份地方稻种资源,其中粳稻56份,籼稻18份(含野生稻3份).通过多个抗性组分进行了系统研究,初步表明大白谷(粳、墨江县)、毫弄早(籼、勐海县)、毫玉浪(籼、勐海县)、疣粒野生稻(野、西双版纳自治州)等具有持久抗瘟性能;其中疣粒野生稻高抗细菌性条斑病,对白叶枯病抗性为0级,接近免疫,中抗稻瘟病.通过对品种多抗性组分分析和品种抗性系统聚类分析,提出在不同生态类型时、空动态的病叶片上的产孢量和病斑表型可作为简易、快速鉴定持久抗瘟性指标.     

Specificity of Distribution of Venation-Anastomosis Patterns in Petals of Phaseoleae (Leguminosae)

Frequency of anastomosis, types of vein anastomosis, and theirpattern of distribution in the standard, wing, and keel of fourspecies (Butea frondosa Wall., Cajanus cajan (Linn.) Millsp.,Dolichos lablab Linn., and Erythrina indica Zoll.), from fourdifferent subtribes of the tribe Phaseoleae (Leguminosae) havebeen analysed. It has been found that the species differ considerablyin these respects. The differences have been found to be significantand species-specific, having a very small range of variationwithin a species. It is suggested that this specificity in thedistribution of vein anastomosis pattern in petal sectors maybe useful in tracing phylogeny.     

Elatostema densistriolatum sp. nov., E. latistipulum sp. nov. and E. cyrtandrifolium var. hirsutum var. nov. (Urticaceae) from southwest China

Two new species and one new variety of Elatostema J. R. Forst. & G. Forst. (Urticaceae) are described from Yunnan and Xizang, China. Habitat details and morphological comparison with similar species are given and discussed. The new taxa proposed are: Elatostema densistriolatum W. T. Wang & Zeng. Y. Wu, E. latistipulum W. T. Wang & Zeng Y. Wu and E. cyrtandrifolium (Zoll. & Mor.) Miq. var. hirsutum W. T. Wang & Zeng Y. Wu.