Some factors affecting the responses of plants to acute and chronic radiation exposures

DOSE RATE DEPENDENCE OF MUTATION RATES FROM Γ-Irradiated POLLEN GRAINS OF MAIZE

“…These results of acute and chronic irradiation were in good accord with those of the relation between chromosome aberration and dose rate of X-rays in microspores of Tradescantia (Sax 1941) and with the effects of acute and chronic irradiation on somatic mutation in flower color of snapdragon (Sparrow et al 1961). Therefore, the results of the present study support the view that mutation of endosperm characters from pollen treatment with gamma-rays is as a rule induced by chromosome aberrations.…”

“…However it has been considered that radiation-induced mutation in the characters of maize endosperm is usually the result of chromosome aberration rather than gene mutation (Stadler 1931; review by Brewbaker and Emery 1962); it has been also reported that somatic mutations in snapdragon are due to minor chromosome deficiencies (Sparrow et al 1961 and others).…”

Elimination of X-Ray Induced Aberrant Chromosomes in the Root Meristems of Two-Rowed Barley

“…Similar conclusions have been made by Sparrow and Cuany (1959), Sparrow et al (1961), Matsumura et al (1963) and others in several additional plant species. Amano and Smith (1965) confirmed that many of the X-ray induced mutations in corn were due to deletions.…”

Cytogenetic Studies on the Effect of Co⁶⁰ γ-Irradiation on <i>Vicica faba</i>

“…7), however, in a nearly negligible per centage (Table 2). Although the percentage of chromosome fragmentation is low, yet it has previously been shown that micronuclei are a fair index of the frequency of fragment produc tion (Sparrow and Singleton 1953).…”