Acta Botanica 35. (1989)
1989 / 1-4. szám
ACTA BOTANICA HUNGARICA 35/1-4 1989 CONTENTS Einfluss erhöhter UV-B Strahlung als Folge des Ozonabbaues der Stratosphäre auf den Stickstoff-Metabolismus von Microorganismen (G. Döhler) ................................................................. 3 The disciplinar roots and some possible interpretations of the life-strategy concept in the lichenology (T. Kiss) ................................................................................................................... 39 Lichens as indicators of air pollution in the Budapest agglomeration (Edit Farkas. T. Pátkai) ............................................................................................................................................................ 55 Foliicolous lichen-mimicry of a rainforest treefrog? (Edit Farkas, T. Poes) .......................... 73 Comparative study of the phytomass production of Middle- and East European steppes (E. Kovács-Láng, T.L. Bystritzkava, R. Mészáros-Draskovits, V.V. Snakin) ...................... 77 An experimental approach to the study of community stability: resilience and resistence (Klára Viráqh) ......................................................................................................................................... 99 The effect of selective herbicides on temporal population patterns in an old perennial grassland community (Klára Virágh) .................................................................................................. 127 Short-term structural changes in sandy grassland comnunities (L. Körmöczi) ............................ 145 Element concentration cadasters in a Quercetum petraeae-cerris forest (Margit Kovács, G. Turcsányi, A. Koltay, L. Kaszab, P. Szőke, L. Nagy) ............................................................... 161 Comparative histological study of diseased and sound Quercus petraea stems (K. Babos) .... 173 Effect of heavy metals inhibiting the growth of plant callus tissues III. (M. Maroti, 3. Bognár) ...................................................................................................................................................... 185 Flower structure of historical and cultivated plums, relationship between morphological characters and self-fertility (D. Surányi) .................................................................................... 199 Floral nectaries and nectar production of sour-cherry cv. "Pándy" clones (Zsuzsanna Orosz-Kovács, 5. Gulyás) ...................................................................................................................................227 Periodicity of nectar production of sour cherry cv. "Pándy" (Zsuzsanna Orosz-Kovács, S. Gulyás, Zs. Halászi) ...............................................................................................................................237 Distribution development and structure of gum-resin producing tissue systems in Vateria indica L. (A.M. Babu, A.R.5. Menőn) ................................................................................................ 245 Reactivation of the dormant lenticels in two Himalayan tree species by the exogenous application of STIK+ and GA^ (H.K. Badola, G.S. Paliwal, A.K. Badoni, 5.P. Sharma) ----- 255 Trapping test of phenolic substances by cross-linked insoluble polymers (A. Fukushima, M. Tamura, T. Hómmá, K. Saito) .................................................................................................................261 Extracellular adhesive substances on bryophyte rhizoids (E.A. Odu) ............................................ 273 Critical notes to Cardamine pratensis agg. in NE Hungary (К. Marhold) ...................................... 279 El género Exostema L.C. Rich. (Rubiaceae) en Cuba (A. Borhidi, Maira Fernandez Zequeira) . 287 Studies on Rondeletieae (Rubiaceae) XI. Critical notes on some Central American species of Rondeletia s.l. (A. Borhidi) ...............................................................................................................509 El herbario Jimeno (Milaqros Moncada Ferrera, P. Herrera Oliver) ................................................ 513 MAGYAR Tudományos akaoími* KÖNYVTARA