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Organization of Club Moss Gametophytes and Juvenile Sporophyte Populations in Pine Forests

Rimgailė-Voicik R., Naujalis J. R., Voicikas A.

Polish Journal of Ecology

2015

Vol. 63, nr 4

467--480

Initial populations of club mosses were investigated in pine forests of southern Lithuania (ass. Cladonio-Pinetum and Vaccinio vitis-idaeae-Pinetum). Results show that populations of lycophyta gametophytes in some forest sites can be abundant (up to 500 individuals in a square meter). All juvenile populations were found in localities where recorded tree canopy cover was 30% or less. Localization of subterranean gametophyte populations was determined by juvenile club mosses. We mapped locations of all Lycopodium L. and Diphasiastrum Holub. juvenile sporophytes and gametophytes that occurred within three randomly selected and excavated 0.25 m2 sample plots at four pine forest sites in different localities in southern Lithuania. The developmental stage of each individual was recorded. Eight out of twelve soil samples from four research localities contained subterranean gametophytes. In total 277 gametophytes and 124 juvenile sporophytes were recorded. The developmental stage and size of the gametophytes varied. Gametophytes were divided into six categories on the basis of external features. Spatial distribution of gametophytes and juvenile sporophytes were evaluated using a nearest neighbor analysis (NNA). Our results suggest that initial populations of gametophytes in pine forests are multi-aged and display a relatively stable degree of spatial aggregation. Greater aggregation occurred among juvenile sporophytes.

Determination of huperzine a in Huperzia selago plants from wild population and obtained in in vitro culture by high-performance liquid chromatography using a chaotropic mobile phase

Szypuła W. J, Kiss A. K, Pietrosiuk A, Świst M, Danikiewicz W., Olszowska O

Acta Chromatographica

2011

Vol. 23, no. 2

339--352

This article is the first report describing a new validated method to determine the content of HupA in Huperzia selago (Huperziaceae) from wild population and obtained in in vitro culture using the chaotropic mobile phase. An aqueous-organic (acetonitrile) mobile phase with an added chaotropic salt (NaPF6) was used. The system of mobile phases ensured very high selectivity and efficiency at up to N = 6683 ± 963 theoretical plates calculated for isocratic mode. A Hypercosil GOLD column, C18 250 × 4.6 mm, and a Hypercosil GOLD precolumn, 5UM 10 × 4 mm, were employed for detection at four wavelengths, 230 nm being analytical. The regression coefficient (R2) of the calibration was 0.9993 over the range 25–1252 μg mL -1. The recovery rates were 98.36–105.1% with RSD <2.9%. The intra- and inter-day precisions, expressed as RSD, ranged from 1.2% to 2.7%. LOD for HupA was 14 ng mL -1 for a signal-to-noise ratio of 3:1. The limit of quantification was 140 ng mL. -1. The huperzine A (HupA) content of the plant material ranged from 0.65 mg g−1 dry weight (d.w.) to 1.59 mg g−1 d.w. (material from wild plants) and from 0.44 to 1.10 mg g−1 d.w. (material from in vitro cultures). Interestingly, in our study, plants of H. selago derived from wild population had one of the highest HupA concentrations recorded for a club moss (1.59 mg g -1 d.w.). The findings demonstrate that H. selago, found in Europe and North America, is an alternative source of HupA, richer than H. serrata. In order to confirm that HupA was present in the alkaloid extracts, HPLC-ESI-MS/MS analyses of the patterns were performed in the positive ion mode. The fragmentation quasi-molecular ion of the standard HupA (m/z = 243, [M+H]+) and the ion with m/z = 243 found in the samples were identical, confirming the compound as HupA.