Zs. P. Komáromy szerk.: Studia Botanica Hungarica 12. 1977 (Budapest, 1977)
Szujkóné Lacza, Júlia; Sen, Subir: Distribution, diversity and equitability of the Hungarian species of Gentiana and Gentianella ciliata L. (Gentianaceae)
These variations may probably be due either to the difference in climatic condition requirements of the four species or to the difference in the developmental pattern of their inflorescence. In the case of G. cruciata the flowering begins in acropetal succession first in the cluster of the main shoots arising from the rhizome and then in the lateral branches. It starts flowering early July and continues to flower for a long time (October). G. asclepiadea is a tall plant and bears flowers on many nodes of the main shoot. The flowering of this species starts in July reaching its maximum in August, but declines considerably in September. In the case of G. pneumonanthe the flowering shoots arise subsequently from the rhizome, thus the time of flowering is delayed though continues for a longer time. The other possibility is that the plants grow in harvested areas and are sometimes injured by animals or human agencies. So it is forced to bear side shoots, and in that case it may continue to flower for a much longer time. G. ciliata is most interesting, since the flowers are terminal, solitary on the main shoot and lateral branches. Accordingly as long as the vegetative development has not been completed flowering is delayed, but once it has been completed, flowering may continue for a longer period. Thus, it starts flowering in the latter part of August, reaching its highest peak in September and continues to November. Thus, G. ciliata is a true short-day species. Table 5 indicates that G. asclepiadea and G. pneumonanthe show lower diversity and equitability according to altitude. On the other hand, G. cruciata shows the highest diversity among the four species under the precipitation factor. The same species shows high diversity and equitability values in precipitation. These values are very near to G. cruciata and G. ciliata under the same factor. G. asclepiadea exhibits lower diversity and equitability in altitude and precipitation factors. We regard "habitat" as a multidimensional biotic factor. So we also studied the diversity of the four species in relation to different habitat types. In this case we found the lowest diversity in G. cruciata and the highest in G. asclepiadea , while in the other two a middle value. Equitability has been found to be maximum in G. cruciata and minimum in G. pneumonanthe . KUSNEZOW (1896-1904) states that Eugentiana "Dieser typus war (typus Pneumonanthe) in der Miocén- und Pliocenepoche in der Waldzone des palaearktischen Reiches weit Verbreitet In das Ende der Tertierzeit muss man auch die energische Ausbildung der jüngeren typen, Frigida, Aptera und Chondrophylla Verlegen". KUSNEZOW's maps 1-4 for the distribution and history (152-153) of Eugentiana show that our species too have relatives in the paleotropical region. This fact illustrates that the species investigated by us also fall in the group of short-day plants. It is quite clear in the case of G. ciliata . In the temperate zone including the Carpathian Basin and in the Great Hungarian Plain, flowering is delayed not only in the present three species of Gentiana but also in the
