Nodulation of legume trees from South East Brazil

Summary An extended survey of nodulation of legume trees from South-East Brazilian forests was conducted. Six new species from the Caesalpinioideae, 23 from the Mimosoideae and 27 from the Papilionoideae are reported to have nodules. Nitrogenase activity (acetylene reduction) was tested for all nodules and rhizobia were isolated from the most active.     

树鼩血红蛋白正常值测定

本文报道了30只产于我国云南的成年树鼩(Tupaia belangeri chinensis)的血红蛋白正常值。结果如下:抗碱血红蛋白均数(％)为0.90±0.09,HbF细胞均数(％)0.10±0.05,Heinz小体生成率均数(％)为12.35±0.81,热变性血红蛋白均数(％)为2.48±0.35,血红蛋白溶解度均数(％) 为83.58±1.12。异丙醇试验为阴性,未见H包涵体。上述结果与人的血红蛋白正常值进行了分析比较。血红蛋白的醋酸纤维素薄膜电泳显示了树鼩Hb的五个区带,树鼩Hb的电泳迁移率慢于人的Hb。     

Changes in mediterranean shrub communities with Cytisus purgans and Genista scorpius

Summary Shrub communities are important in the mediterranean landscape and linked very much with human activities. The permaneney and the spreading of these communities are related to biological characteristics of the dominant species which control the patterns of changes in structure, richness, types of life forms, and ability of colonization by trees. In this paper, changes in communities are analysed and compared for Cytisus purgans and Genista scorpius (both Papilionaceae). For both communities the schemes of origin and spreading are rather the same: overgrazing and fire play a prominent role. Changes in structure show different stages emphasized by the types of distribution of the chlorophyll containing stratum. There is a direct relation between changes in structure and changes in species richness and life form spectrum: richness decreases generally from the second or third year after fire. According to the dryness of the stand therophytes may or may not be important in the youngest stands. The colonization of the shrub communities by trees is dependent on several conditions, either on the shrub community itself, or on the plant-matrix surrounding the shrub community patch and also on animals; man, too, plays an important role. In conclusion we think that the above-mentioned changes in shrub communities fit the inhibition model proposed by Connell & Slatyer (1977); but, more generally it seems that the plant successions observed in our regions follow both, this model and the facilitation and tolerance models of the same authors. Linked with this fact, it seems that the successions show generally fluctuating values of richness as is suggested by Whittaker (1975). We think that plant succession must be well analyzed at different levels of organization and include the study of the influences man and animals may have.Plant nomenclature follows Fournier (1961); for birds see Peterson et al. (1967).We are very much indebted to Ch. Rimbault for her contribution to the translation of this paper.     

Sorghum-sudan green manure; Its effect on nursery stock

Summary The use of sorghum-sudan green manure has recently attained popularity among nurserymen because of the assumption that toxic excretions of these hybrids control root-rot fungi. Greenhouse trials of 2-year duration have revealed that green manure of sorghum-sudan inflicts severe damage of tree seedlings, largely by eradication of mycorrhiza-forming fungi. Early plowing under of green manure, periodic watering, and late fall seeding of nursery crop may alleviate phytotoxicity of the sorghum-sudan residues, but the biocidic properties of these plants defeat the primary purpose of using green manure in contemporary nurseries, namely the biodegradation of toxic compounds.Research supported by the College of Agricultural and Life Sciences, University of Wisconsin, Madison, and the Wisconsin Department of Natural Resources.     

Die Feinstruktur der Kehlkopfmuskeln des Laubfrosches,Hyla arborea arborea (L.), im Vergleich zu einem Skelettmuskel

Zusammenfassung Um Hinweise auf die Funktion des Kehlkopfes bei der Rufabgabe zu bekommen, führten wir eine vergleichende elektronenmikroskopische Untersuchung an den vier Kehlkopfmuskeln rufaktiver Laubfrösche durch. Zum weiteren Vergleich studierten wir auch einen Extremitätenmuskel.Die Kehlkopfmuskeln sind untereinander gleich gebaut, unterscheiden sich aber in mehrfacher Hinsicht vom Extremitätenmuskel: Ihre Myofibrillen sind nur ein Drittel so dick. Die Kehlkopfmuskeln enthalten sehr viele, auffallend große und dichte Mitochondrien; das sarcoplasmatische Retikulum ist mächtig entwickelt. Sie enthalten außerdem sehr viel Fett, das stets mit den Mitochondrien assoziiert ist. In beiden Muskeltypen kommt Glykogen vor; seine Menge ist in den Kehlkopfmuskeln jedoch größer als im Extremitätenmuskel. Die Zahl der motorischen Endplatten ist in den Kehlkopfmuskeln 25 mal höher als im M. plantaris longus. Die Zahl der Triaden pro Sarcomer und ihre Anordnung ist bei den beiden Muskeltypen gleich.Die Kehlkopfmuskeln winterstarrer Hyla-Männchen unterscheiden sich in ihrem Feinbau und Fettgehalt nicht von den Muskeln rufaktiver Tiere.

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The fine structure of the laryngeal muscles of the tree frog, Hyla arborea arborea (L.), compared with that of a skeletal muscle

Summary In order to obtain information on the function of the larynx during vocalization, a comparative electron microscopic study was made of the four laryngeal muscles of male tree frogs druing their vocalizing phase. A skeletal muscle (m. plantaris longus) was examined for comparison.The fine structure of the laryngeal muscles is uniform, but differs from skeletal muscles in several respects: the diameter of the myofibrils of the laryngeal muscles is only 1/3 that of the skeletal muscle. They contain many strikingly large and dense mitochondria. There is a strongly developed sarcoplasmic reticulum. Laryngeal muscles contain large quantities of fat which is always associated with mitochondria. Laryngeal muscles contain more glycogen than skeletal muscle. The number of motor endplates in laryngeal muscles is 25 times larger than in m. plantaris longus. The number of triads per sarcomere and their location is the same in both types of muscle.The laryngeal muscles of hibernating and active tree frogs do not show any difference with respect to fine structure and amount of fat.

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.     

Dendroecological analysis of a longleaf pine Pinus palustris forest in Mississippi

A climate model with time varying parameters was fit to longleaf pine (Pinus palustris) tree rings collected from the proposed Harrison Research Natural Area of the De Soto National Forest in southern Mississippi. The purpose of the analysis was to determine if any unexpected disturbances had influenced the growth of the trees. Current September temperature, August rainfall and February Palmer Drought Severity Index (PDSI) were found jointly to be the best variables in the model to predict growth. August rain had a constant significant effect on growth and February PDSI was not significant except between the years 1968–1983. It was concluded that the Harrison area has been in equilibrium for the past 50 years since no apparent outside influences have caused the trees to become less sensitive to climate. Thus, the forest is a good candidate for a Research Natural Area.Abbreviations (RNA) Research Natural Area     

树鼩(Tupaia belangeri Wagner)三个亚种的染色体比较研究

本文对中国西南部树鼩(Tupaia belangeri)三个亚种的染色体特征进行了详细比较。结果表明滇西亚种(T.b.chinensis),越北亚种(T.b.tonquinia)和瑶山亚种(T.b.yaoshanensis)的染色体数目均为62:G带和C带基本相似;Ag-NORs的数目相同(4—6个),有相似的分布。应用复制带的技术,确定了雄性树鼩的Y染色体。本结果为树鼩的分类鉴定提供了细胞遗传学依据。     

Structure and dynamics of a tropical dry forest in Ghana

Forest under low rainfall (averaging 745 mm yr^-1) on the Shai Hills in S.E. Ghana has redeveloped following cessation of farming in the 1890s. Forest stature is low, with a canopy at about 11 m, principally of three species, Diospyros abyssinica, D. mespiliformis and Millettia thonningii. Drypetes parvifolia and Vepris heterophylla are common understorey trees. Twelve species of woody liane were recorded. Species of thicket vegetation in the area were also present at low density. Most species are evergreen.Tree mortality averaged 2.3% yr^-1 and exceeded recruitment (1.5% yr^-1). Differences between species in mortality and recruitment were pronounced: canopy species showed a small decline in density; understorey species increased markedly and the thicket species declined. Seed production was very variable, but seedling establishment was very poor for all species. Seedling mortality was high (11% yr^-1) especially for small seedlings. These population trends probably represent the latter stages of succession of forest regrowth after farming about 100 years ago.Compared with tropical rain forest, Shai Hills forest has similar relative tree diameter growth (1–3.5% yr^-1), mortality and recruitment rates, and small-litter fall (5.52 t ha^-1 yr^-1).Shai Hills forest differs from rain forest by its short stature, relatively few (evergreen) tree species, poor regeneration from seed, high soil nutrient status and low rainfall. Similar forests have been reported in east Africa and in parts of New Guinea.Abbreviations dbh diameter at breast height (1.3 m) - gbh girth at breast height died May 1984     

A field experiment on dispersal of newly emerged adults ofMonochamus alternatus (Coleoptera: Cerambycidae)

Newly-emerged adults of Monochamus alternatus aged 1 to 5 days were code-numbered with lacquer paint and released by placing them on the trunks of one or two trees in a Pinus thunbergii stand at weekly intervals during the beetle emergence period from 1980 to 1983. Beetles were captured at weekly intervals from one week after the first day of release. Determinations were made on the distance and direction of beetle dispersal during a week after release and analysed by a method of Inoue (1978). When the stand canopy was closed, the rate of beetle's stay on trees was 0.56 per week. The beetles dispersed at random by walk and flight. When the pine stand was sparse, the rate of beetle's stay on trees was 0.02–0.30 per week. They dispersed at random by flight. The average distances traversed were estimated to be 7.1–37.8 m for the first week after emergence. Using other method, the average distance traversed was estimated to be 10–20 m for each week through the first 3 weeks after release. The results of stepwise multiple regression analysis and a simple field experiment suggested that the dispersal of newly-emerged beetles was affected by stand density, number of beetles emerging from individual dead trees, maximum air temperature, and precipitation.     

人和猴T淋巴细胞表面TRBC受体及其配体不同于E2分子和CD2的配体

T淋巴细胞表面的TRBC受体不同介导E花结形成的E受体(CD2)和E2分子。CD2的配体,人红细胞表面的CD58(LFA-3)和绵羊红细胞表面的T11 TS,S42,S14及S110-220,与TRBC受体的配体无关,TRBC玫瑰花结的形成是通过不同于E花结和人自身玫瑰花结的受体-配体相互作用来实现的,进一步表明,人和猴T淋巴细胞表面和TRBC表面,可能都有独特的蛋白质分子介导TRBC玫瑰花结的形成。