Ábrahám Levente (szerk.): Válogatott tanulmányok IV. - Natura Somogyiensis 15. / Miscellanea 4. (Kaposvár, 2009)
Bódis Judit - Molnár Edit: Himantoglossum adriaticum H. Baumann populáció hosszú távú monitorozása a Keszthelyi-hegységben
36 Natura Somogyiensis In spite of the considerable differences between the extreme values of reproductive traits studied, among them three (except for number of seedpods) showed low temporal variability in the whole study period (cf. Table 1). In the case of the number of seedpods, however, the variability was of very large extent indicating the great uncertainty in the annual fecundity. The number of flowers and the height of the stem are similarly stable characteristics in the case of the Dactylorhiza lapponica (Oien and Moen 2002) and the number of flowers per inflorescence does not vary greatly in Tipularia discolor and Liparis lilifolia populations. Observed differences in flowering and fruiting are most likely to be influenced by historical events at the individual level, especially costs associated with sexual reproduction and leaf herbivory (Whigham and O’Neil 1991). Otherwise, the height of spike and the number of flowers per inflorescence were also a year-depending characteristics in the case of Ophrys apifera (Wells and Cox 1991). The rate of the fecundity is usually a variable character and the low levels of fruit-set are typical among wild orchids (Proctor and Yeo 1973, Summerhayes 1968). Only 7% of the flowers got fertilized in Orchis purpurea populations in Belgium, and the number of seedpods seems to be depended on the number of flowers on spike. The large inflorescences produced significantly more fruits than the smaller inflorescences and this phenomenon proved to be independent of population (Jacquemyn et al. 2002). Other orchid species show just the opposite. Fruit-set production is not related to the number of flowers or their density, suggesting that pollination and/or seed set varies between years (Carey et al. 2002, Carey and Farrell 2002). For H. adriaticum 2004 was an extremely good year, when the orchid produced 14 seedpods per plant, in spite of the fact that the number of flowering plants was relatively low and the average number of flowers per plant was the lowest in that year. No correlation was found between the fecundity rate and the height of flowering plants as well as the average length of the inflorescences. In the case of H. hircinum populations in South-England 1993 was an outstanding year, when the mean number of seedpods produced per plant was exceptionally high, nearly 20, in contrast with the regular 5 or even lower values (Carey et al. 2002). No significant relationship was found between the fruit set and inflorescence size in the case of Dactylorhiza fuchsii and Epipactis helleborine (Waite et al. 1991). The reproductive success was not correlated with the number of flowers, but the correlation with the length of inflorescence was found to be significant by other investigations in the case of Dactylorhiza fuchsii, in Bohemia (Janeckova and Kindlmann 2002). Probably, the complicated pollination biology also contribute to the variations of reproductive traits. One of the most important feature is whether the flower produces nectar or not. There is no certainty in the case of the Himantoglossum genus, that there is nectar in the spur or not (Carey and Farrell 2002). Another important factor is the weather at the time of flowering. If the weather is favourable for the pollinator insects, the fecundity rate is better (Light and MacConaill 2002). Conclusion There are only few data about Himantoglossum adriaticum, because the species was only described not long ago. Although the total number of population, flowering frequency could not be estimate if only flowering individuals are used for monitoring,
