MICROSPOROGENESIS AND DEVELOPMENT OF POLLEN GRAIN IN HYBRIDS OF SEA BUCKTHORN (Hippophaё rhamnoides L.) OF VARIOUS ECOGEOGRAPHIC ORIGIN

Abstract

, E, P vitamins, polyunsaturated fatty acids, caro-tene, 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. hy-brids of various ecologo-geographic origin of Nizhny Novgorod State Agricultural Academy breeding. The stage of male gametophyte development was deter-mined 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. Keywords: sea buckthorn, hybrids, microsporogenesis, sum of positive temperatures.