The Different Stability of Chromosomes and the Nature of Mitosis

Embryological features, pollen and seed viability of Arnica montana (Asteraceae) – a threatened endemic species in Europe

“…In contrast with the apomictic species, in which a high percentage of sterile pollen grains is observed (Afzelius 1936, Gustafsson 1937, Babcock and Stebbins 1938, Fagerlind 1939, Battaglia 1947, in Arnica montana we found the formation of morphologically uniform and highly fertile pollen in the majority of the anthers.…”

Radiation Response of Soaked Barley Seeds

“…OAKED seeds have been shown to be damaged more by X-rays than S non-soaked seeds (PETRY, 1921 ; STADLER, 1928; GUSTAFSSON, 1937GUSTAFSSON, , 1947GELIN, 1941;EHRENBERG et d., 1953). Froin these studies it was widely accepted that the radiation susceptibility of a biological system increases with increasing water content.…”

The Cytological Effect of Different Seed-Treatments in X-Rayed Barley

“…The fragments may vary very much in appearance, size and number, but are probably for the most part chromosome fragments (double).In the present investigation longitudinal sections were exclusively used, and disturbed or undisturbed cells were determined at the anaphase or telophase stage. As it was probable, according to GUSTAFSSON (1937), that the frequency of disturbances varied in different tissues of the root, the determinations were made partly for the periblem and the dermatogen, partly for the plerome. The periblem Hereditas X X V I I .…”