Practical suggestions for successful immunoenzyme double-staining experiments

Summary Many methodologies exist to perform an immunoenzyme double staining. Hence, the practical problem arises as to which of these methods is optimal for one's own experimental design. A process of selection is described which is derived from our own practical experience. First, a general strategy is outlined for the handling of tissue sections to be used for multiple staining methods. Secondly, the selection of an appropriate immunoenzyme double-staining concept is made using a flow chart. Thereafter we give criteria for the definitive selection of an immunoenzyme double-staining protocol based on the characteristics of the tissue or cell type under study. Particular attention is given to the selection of appropriate detection systems, applying enzymes or gold particles, and good contrasting colour combinations. The problems of visualizing co-localization using immunoenzyme double staining are dealt with, and suggestions are made to adapt the method, if necessary, in order to optimize it.This paper (in modified form) is part of the thesis of C. M. van der Loos: Free University Press 1992, Amsterdam, The Netherlands (ISBN 90-5383-081-2).     

EFFECTS OF FERTILIZATION ON EPICUTICULAR WAX MORPHOLOGY OF NEEDLE LEAVES OF DOUGLAS FIR,PSEUDOTSUGA MENZIESII (PINACEAE)

Fertilized stands of Pseudotsuga menziesii were found to have glaucous needles. We investigated the morphological and quantitative characteristics of the epicuticular waxes of needles of fertilized and control trees. Glaucousness was caused by ornate tubular epicuticular wax. Dipping needles in chloroform, which dissolves waxes, eliminated the glaucous appearance. Based on cryostage scanning electron microscopic observations, the epicuticular waxes in the nonstomatal region were much more ornate on the needles of the fertilized trees (experimental needles) than in unfertilized trees (control needles). The stomatal region in both experimental and control needles showed similarly ornate waxes. Quantities of waxes were similar in experimental and control needles. The glaucousness was not the result of greater quantities of wax; rather, fertilization altered wax morphology in the nonstomatal regions.     

Revision of Bomarea subgenus Sphaerine (Alstroemeriaceae)

The subgenus Sphaerine of Bomarea (Alstroemeriaceae) recently contains 33 validly published names. Extended field studies in Peru and extensive investigation of herbarium material revealed the urgent necessity for a revision. As a result, the number of species is reduced to 12, among them two species are newly described. 9 species are members of an other subgenus. A key to determine the species is given in English and Spanish. The typical growth form and its variability, habitat preferences and distribution are discussed separately for each species.     

Euhemerobe Kalk-Kieferngesellschaften der Kleinen Karpaten

Man made stands withPinus nigra Arn. were studied on limestone bedrock. They were planted out on biotops of previous calciphilous beech or xerothermophilous oak forests. The analysis of present phytocenological composition and the changes in ecological conditions, especially of nitrogen content in the soil, conduce to their classification, following the conception ofHada? andSofron (1980), as a new euhemerobic forest community, associationClematidi vitalbae-culti-Pinetum nigrae.     

Einige neue oder bemerkenswerte Flechten mit gyalectoiden Apothecien von Nord-Indien und Nepal

This paper presents the results of taxonomic investigation of 8 species of lichens with gyalectoid apothecia collected in North-India and Nepal. Four species are recognized as new:Dimerella isidiata (sp. nova),D. nepalensis (sp. nova),Gyalideopsis lithophila (sp. nova) andRamonia nepalensis (sp. nova). Four species are reported for the first time from Nepal:Coenogonium moniliforme, Gyalectidium caucasicum, Gyalidea lecideopsis andG. scutellaris.     

The grass megagametophyte and its possible phylogenetic implications

The structure of the grasses megagametophyte is considered to be characteristic enough as to deserve a particular place in the megagametophyte typology. Furthermore, it is compared with those of other Monocotyledonous families to point out embryological affinities.Both are members of the Carrera del Investigador (Conicet, Argentina).     

Pleurotrema epiphylla Vězda sp. n., eine neue foliikole Flechte aus Zentral-Afrika

Eine nèue foliikole Flechte (Pleurotrema epiphylla sp. n.) aus Zaïre (Zentral-Afrika) wird beschrieben. Die systematischen Beziehungen der neuen Art zu den anderenPleurotrema-Arten und die Stellung der GattungPleurotrema innerhalb der FamilieParatheliaceae wird kurz diskutiert.