Sel’skokhozyaistvennaya Biologiya [Agricultural Biology], 2013, № 3, p. 59-65 UDC 634.74:581.331.2 MICROSPOROGENESIS AND DEVELOPMENT OF POLLEN GRAIN IN HYBRIDS OF SEA BUCKTHORN (Hippophaё rhamnoides L.) OF VARIOUS ECOGEOGRAPHIC ORIGIN 2 Nizhny Novgorod Branch of Russian Forest Protection Center, 5, ul. <...> Telmana, Nizhny Novgorod, 603034 Russia Received November 22, 2010 1 Nizhny Novgorod State Agricultural Academy, 97, prosp. <...> Gagarina, Nizhny Novgorod, 603107 Russia e-mail: Lapshin-da@yandex.ru T.N. Kuznetsova1, , D.A. Lapshin2 S u m m a r y Hippophaё rhamnoides L. is of interest as feed and medicinal plant. <...> Its fruits contain the C, B1, B2, E, P vitamins, polyunsaturated fatty acids, carotene, other biologically active compounds. <...> The temperature conditions during winter-spring period is main limiting factor in sea-buckthorn introduction, and the male generative sphere is the most sensitive to unfavorable conditions. <...> The authors investigated a microsporogenesis in Hippophaё rhamnoides L. hybrids of various ecologo-geographic origin of Nizhny Novgorod State Agricultural Academy breeding. <...> The stage of male gametophyte development was determined on squash temporary preparation. <...> As result of analysis the two groups of hybrids were revealed, which differ on the time of beginning and a course of the definite stages of microsporogenesis. <...> The first group involves the hybrids with prevalence of morphophysiological determinants of Katunskii ecotype (Debyut, 5/87, 1/89 and 1/91), the second one — with prevalence of morphophysiological determinants of Baltic ecotype (Gerakl, 31/89, 1/90 and 5/93). <...> In hybrids of the first group the beginning of microsporogenesis and the formation of microspore tetrads occur at the low sum of positive temperatures (respectively, 48.5-49.5 and 114.8-118.5 С) than in hybrids from second group (62.0-71.1 and 135.6-147.0 С). <...> However, the maturation of pollen and blossoming (anthesis) of male plants in studying ecotypes pass practically at the same time, at the sum of positive temperatures from 171.8 to 216.6 С and from 276.3 to 343.9 С, respectively. <...> In ontogeny plant organisms are exposed to various biotic and abiotic factors, one of which often becomes the limiting factor so significant that the other can be neglected. <...> Knowing the influence of external factors on reproductive process of plants <...>