Asteraceae

In a course of investigation of seed productivity under the pollenless regime of flowering in 154 natural populations of 98 species of 46 the Asteraceae genera from Saratov province gametophytic apomixis has been discovered in populations of 24 species from 14 genera. For the first time this mode of reproduction has bean revealed in 7 genera and 16 species of the family (Hieracium largum, Pilosella echioides, Tragopogon dubius, Lactuca serriola, Scorzonera ensifolia, Chondrilla latifolia. Ch.

We have studied the characteristics of seed reproduction Artemisia 14 species from various parts of the Saratov region. It is shown that a population of five of them (A. vulgaris, A. salsaloides, A. dracunculus, A. glauca, A. austriaca) are characterized by high (at least 20-30%) frequency of gametophytic apomixis in plants, and three species (A. abrotanum, A. absinthium, A. armenica) have lower (10-15%) frequency of gametophytic apomixis.

The morphological variability in populations of Chondrilla was subject to the numerical analysis using the unweighted pair group method with arithmetic mean (UPGMA). The study showed that out of the seven species of the genus found in European Russia, it is only C. ambigua that has the status of undoubted species. A distinct difference is observed between the two groups of populations: the first group comprising C. juncea, C. latifolia, C. brevirostris, and the mixed population of C. juncea/graminea; and the second group comprising the populations of C. graminea and C.