Boros István (szerk.): A Magyar Természettudományi Múzeum évkönyve 8. (Budapest 1957)

Baksay, L.: The cytotaxonomy of the species Chrysanthemum maximum Ram., Centaurea montana L., Serratula lycopifolia (Vill.) Kern., and Bupleurum falcatum L., ranging in Europe

Serratula lycopifolia (Vili.) Kern. ( = S. heterophylla Desf.) is rather rare within its range (see Map), the plant and its collecting localities are real rarities. In our home flora, it lives in the association of Quercetum pubescentis, a thermophilous, woodland — steppe plant. The genus consists of about 50 species, the main centers of its abundance are Iran and Turkestan, also Siberia. Nearly related to 5. lycopifolia are : S. radiata (W. et K.) MB. ; S. isophylla Claus (Central Russia), and S. centauroides L. (Altai Siberia). The chromosome number of S. lycopifolia, collected in the Mts. Mecsek, the Mts. Vértes (in the area of the Hungarian Central Mountains) is 2n = 60 (4 x ) ; that of 5. radiata, collected in the hills around Budapest, 2n = 30 (2 x). The shapes of the chromosomes are wholly similar in both species, with 4 satellites in the diploid, and 8 in the tetraploid (fig 1 b). Of the related species mentioned above, S. radiata and S. isophylla stand nearest to 5. lycopifolia, with regard to their external morphology. The capitulum of this latter is larger, its stem not ramifying, simple ; the other two species have smaller inflorescences and usually ramify. In Hungary, the blossoming time of S. lycopifolia is about 3 weeks earlier than that of S. radiata. According to the data of the Soviet flora, its flowering time falls between those of 5. isophylla (June) and S. radiata (July-August), that is, June—July. S. lycopifolia is the polyploid of one of these species. Unfortunately, we do not know the chromosome conditions of 5. isophylla. On the basis of stoma measurements, as an auxiliary foothold to deal with this problem, taken from the epidermis, we know that the stoma of 5. radiata and S. isophylla are of identical sizes, those of S. lycopifolia are larger (from Russian plants). It is a striking character of S. lycopifolia that it proliferates very well vegetatively, by subterranean'stolons (presumably the result of polyploidy), it builds locally extensive colonies and produces, according to the observations of the author, very few flowery shoots so that its propagation by seeds is considerably limited ; this will probably also be the cause of its sporadic dispersal. The chromosome number of S. radiata in Russia is, according to Poddubnaia (1935), n = 30, counted in the meiosis of the embryonic sac. This tetraploid number, of not erroneous, cannot be explained by the range of the species. Namely, it is the old-standing observation of cytologists and gene-oecologists that, in the majority of the cases, polyploids are much more suited for the conquest of new areas with a differring oecology in the dispersal of the species than its diploid individuals. Now, by the ancient center of the genus, S. radiata wandered from the east to the west and not oppositely, and the starting species must have been the diploid originating not in Europe but somewhere in the Turkestan or the Caucasus. The few herbarium specimens from Russia do not differ from the European ones. This problem could be solved only by cytological examinations on recent Russian plants. S. lycopifolia and S. radiata are oecologically very similar. On the basis of our home observations, the former one occurs in pubescent oakwoods, and there too in its thinning portions, in carstic shrubberies ; the latter one occurs in rather more open places, on grassy slopes, yet also in copses. The recent range of the species in Russia, between latitudes 48—53, was under the ice-sheat that is, the border of the ice extended along this area. (Wulff) Both species are strongly thermophilous, having wandered (together with woodland-steppe elements) toward the west, in the warming-up period after the postglacial era.