cereals

Apomictic species in genus Hierochloё R. Br.

The article is dedicated to cytoembryology investigation of two cereals species: HierochO glabra (two populations from Kamchatka) and H. repens (one population from Lower Volga region). The plants of these populations are characterized by high frequency of ovules with few (2-4) megagametophytes (5,7; 8,6 и 25%, respectively). This point to the apoarhespory - development of unreduced embryo sacs from somatic nucellus cells.

Aposporiy in representatives of the genus Koeleria Pers.

The article presents the results of cytoembryological analysis of two cereal species: Koeleria cristata (L.) Pers. и K. sabuletorum (Domin) Klok. It was found that in the plants of both species many ovules (23 and 30%, respectively) contain from 2 to 5 megagametophytes. In the ovules the multiple embryo sacs were on the same or different development stage. In the nuccelus of some ovules near the embryo sac the big cells could also be observed. The morphology of these cells liked to initial cells of aposporous embryo sacs.

Pollen-ovule ratios in cereals with different mode of reproduction

The article presents the results of studying of pollen-ovules ratios (P/O), the quality and size of the pollen in wild cereals with different mode of reproduction (sexual: Alopecurus pratensis L., Elymus caninus L., Glyceria fluitans (L.) R. Br., Poa annua L., Zerna riparia (Rehm.) Nevski; facultative apomict: Dactilis glomerata L., Koeleria cristata (L.) Pers., Festuca valesiaca Schleich.