Katalog - Lichenological literature

2307

Thomas M. A., Nash III T. H., Gries C. (1997): Ecophysiological comparison of two tropical/subtropical lichen species: Dictyonema glabratum from an alpine habitat and Coenogonium interplexum from a lowland forest, Bibl. Lichenol., 67: 183-195

The effects of variation in temperature, photon flux density and thallus water content levels on CO2 gas exchange were examined in two tropical lichen species: Coenogonium in (et-plexum, an algal dominated ascolichen, and an alpine form of Dictyonema glabratum, a basidiolichen with a cyanobacterial symbiont. The basic C02 gas exchange patterns clearly reflect the habitats from which the material was collected. For example, within the conditions of our experiments, D. glabratum exhibited a temperature … Read more...

2306

Winkler J.B. & Kappen L. (1997): Photosynthetic capacity of endolithic lichens from South-Africa, Bibliotheca Lichenologica, 67: 165-181

The photosynthetic perfonuance of four lichen species growing as endoliths or as cryptoendoliths in sandstone was investigated. Measured were net photosynthesis and dark respiration of Lecidea aff. sarcogynoides and Sarcogyne cf. austroafricana in Tshipise sandstone from Mutamba Ranch (northern Transvaal) in a semi-arid region of South-Africa and Lecidea aff. sarcogynoides, Lecidea confluentula and Lithoglypha aggregata in Clarens sandstone from the Golden Gate Highlands National Park (eastern Orange … Read more...

2305

Dietz S. & Hartung W. (1997): Regulation of the abscisic acid content in the two lichen species Hypogymnia physodes and Peltigera praetextata, Bibliotheca Lichenologica, 67: 137-144

We investigated the ABA content of Hypogymnia physodes and Peltigera praetextata sampled at natural habitats at different times of a year. The ABA content showed high variability in both lichen species and was far higher in H. physodes than in P. praetextata at ever)' time by a mean factor of about 20. Conjugation of 14C-ABA was only small in wet thalli as well as in desiccating thalli, and no oxidative degradation could be found. Efflux experiments showed relative high rate constants for ABA exchange … Read more...

2304

Máguas C., Valladares F., Brugnoli E., Catarino F. (1997): Carbon isotope discrimination, chlorophyll fluorescence and quantitative structure in the assessment of gas diffusion resistance of lichens, Bibl. Lichenol., 67: 119-135

In this study, we examine the potentialities of carbon isotope discrimination, chlorophyll fluorescence and quantitative structure techniques for the evaluation of gas diffusion resistances in lichens. For that, a comparative analysis was performed between two species of Lobaria, one with a cyanobiont exhibiting CO: concentrating mechanism (CCM) activity (L. scrobiculata) and the other with a phycobiont lacking CCM activity (L. pulmonaria). Carbon isotope discrimination (A) was affected by the CCM … Read more...

2303

Scheidegger C., Frey B., Schroeter B. (1997): Cellular water uptake, translocation and PSII activation during rehydration of desiccated Lobaria pulmonaria and Nephroma bellum, Bibl. Lichenol., 67: 105-117

The time of regaining photosynthetic activity was shown to be extremely fast after water was added to the thallus of desiccated Lobaria pulmonaria. Rapid increase of the fluorescence yield evidenced a recovery of photosynthetic activity within less than 20 seconds. X-ray microanalysis of thalli re- hydrated with a solution containing tracers for apoplastic (La) and cell-to cell- transport (Rb) showed that the water was translocated in the apoplast, irrespective whether the fungal hyphae were thick-walled … Read more...

2302

Proksch P. & Hesbacher S. (1997): Lichen products in lichen-herbivore interactions, Bibliotheca Lichenologica, 67: 91-102

The role and fate of lichen compounds in interactions of lichens with polyphagous and oligophagous herbivores including insects and snails was studied. Several frequently occurring lichen products such as usnic acids or vul- pinic acid are highly toxic and deterrent towards polyphagous pest insects like larvae of the noctuid Spodoptera littoralis that are not adapted to feed on lichens. Members of the lepidopteran family Arctiidae, however, which feed on lichens in nature do not only tolerate dietary … Read more...

2301

Zorer R., Türk R., Stocker-Wörgötter E. (1997): Resynthesis of the lichen Cladonia fimbriata from the axenic cultures of the isolated symbionts, Bibl. Lichenol., 67: 85-89

Successful resynthesis was achieved between the mycobiont of Cla- donia fimbriata and its Trebouxia photobiont. High concentration of fumarprotocetraric acid was detected by TLC analysis of acetone extracts from the synthesized lichen thallus and podetia. The success of the resynthesis experiments depends on the light and temperature conditions and especially on the humidity. The alternation of moist and dry' periods is necessary for the development and for the morphogenesis of the lichen and probably … Read more...

2300

Sokol R. (1910): Okolí české Kubice, Rozpravy České Akademie, 19(25): 1-19