The climatic influences upon the pollen development of the Italian hemp

Abstract

1. The microsporogenesis of the Italian hemp, grown up under Moscow and Caucasia conditions has been investigated. 2. The Italian hemp cultivated in Caucasia had with a very few exceptions, a quite normal course of pollen development. 3. The same hemp grown up in Moscow district showed a large number of different irregularities during the microsporogenesis. The most striking of them were: fusion of the nuclei in the archesporial tissue, in prophases and in the first and second telophases, failure of conjugation of chromosomes, formation of the restitution-nuclei in the first and second divisions etc. 4. The young pollen grains of the Italian hemp in Caucasia had regular round forms and a small coefficient of variation in size. 5. The young pollen of the Italian hemp in Moscow district had a great number of deformed, gigantic, dwarfish, polynuclear etc. grains. 6. As all the conditions, except the climatic ones, were the same in the both cases, we find that such a difference in the course of microsporogenesis may only be attributed to climatic influences.