The present paper deals with the morphological, anatomical structure of achenes in the East Asian species of Rhaponticum, Klasea Serratula and Synurus. The structure of pericarp epidermal cells, mesocarp, has been described, as well as the structure of testa epidermal cells. The specific characters of the genera, as well as the identification characters of the species, are described.

We tested the differentiation and morphogenetic capacity of floral organs of Iris ensata, I. setosa , and I. sanguinea cultured in vitro . Organogenesis through direct formation of shoots from explants, callogenesis, and floral organogenesis were demonstrated in I. ensata callus culture in vitro . These processes depended on the plant species and on the content of phytohormones in the medium. Adventitious shoots proved to develop on the basal part of the perianth tube and on the apical part of the ovary, while roots were not formed. Direct organogenesis was induced by the following phytohormones: α -naphthylacetic acid and 6-benzylaminopurine for I. ensata and 2,4-dichlorophenoxyacetic acid and 6-benzylaminopurine for I. setosa and I. sanguinea ; while callogenesis was induced by 2,4-dichlorophenoxyacetic acid. The obtained data indicate that development of adventitious structures from iris floral organs requires the presence of 6-benzylaminopurine in the growth medium. PLANT PHYSIOLOGYŠ š

Flavonoids uncharacteristic of intact plants were isolated from callus tissue of Iris ensata and were identified as 5-hydroxy-4′-methoxyflavone, 5-hydroxy-3′-methoxyflavone, and 5-hydroxy-2′-methoxyflavone using PMR and mass spectrometry. It was proposed that the lack of growth of callus tissue after changing cultivation conditions was related to the inhibiting effect of these flavones on cell proliferation.Key words: Iris ensata, Iridaceae, callus tissue, 5-hydroxy-4′-methoxyflavone, 5-hydroxy-3′-methoxyflavone, 5-hydroxy-2′-methoxyflavone.Flavonoids are the most studied group of secondary plant metabolites from the Iridaceae family [1]. Information on the contents of these compounds is used in chemotaxonomic studies of representatives of this family. The flavonoid composition is known for almost 60% of Iris species [2]. However, little attention has been paid to the secondary metabolites of in vitro tissue from cultivated species of this genus. It has been demonstrated that Iris cell cultures contain terpenoids [3,4]. Earlier we studied the qualitative pigment composition of I. ensata Thunb. heterotrophic callus culture [5]. A determination of the nature of pigments from callus tissue of this plant indicated an acculumation of flavonoids. The goal of the present work was to isolate and identify red pigments from callus tissue of I. ensata.Extract of I. ensata callus tissue contained three isomers of 5-hydroxy-monomethoxyflavone. The isolated compounds were identified as 5-hydroxy-2-(4-methoxyphenyl)-chromen-4-one (5-hydroxy-4′-methoxyflavone) (1), 5-hydroxy-2-(3-methoxyphenyl)-chromen-4-one (5-hydroxy-3′-methoxyflavone) (2), and 5-hydroxy-2-(2-methoxyphenyl)-chromen-4-one (5-hydroxy-2′-methoxyflavone) (3).Compound 3 and other lipophilic flavones unsubstituted at the 7-position were observed in secretory emissions of aerial organs of plants from the genus Primula [6,7]. It has been found that flavones found in leaves of P. veris are synthesized in in vitro cultivated tissues of this plant [8].The results suggest that the spectrum of synthesized secondary-exchange compounds changed in callus culture of I. ensata when compared with the intact plants. According to the literature, intact plants of this species contain flavonoid pigments of the anthocyan [9, 10], flavone, and xanthone [11] types. However, the dominant pigments in callus tissue were lipophilic flavones 1-3 uncharacteristic of this plant.Our results for the pigment composition of I. ensata callus tissue showed that flavone formation in tissue was suppressed in the subcultivation medium [5]. However, the change of cultivation conditions (reduced content of phytohormones, increased concentration of saccharose, change of pH) favored flavonoid accumulation and inhibited callus growth.It was noted that the synthesis of secondary compounds in isolated instances was related to a slowing or cessation of cell proliferation [12,13]. Apparently the flavonoids identified by us and compounds similar to them in biogenetic origin were responsible for the suppression ...

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