BIOLOGICAL EFFECTS PRODUCED BY X-RAYS AND THERMAL NEUTRONS IN DIPLOID AND HEXAPLOID SPECIES OF AVENA

Journal Article · Thu Nov 01 04:00:00 EST 1962 · Radiation Botany

DOI:https://doi.org/10.1016/S0033-7560(62)80119-7· OSTI ID:4720860

Koo, F K.S.

Differential responses of diploid and hexaploid oats to radiation and comparisons of effects produced by x rays and thermal neutrons are reported. The biological efiects produced by the two iomzing radiations were measured in terms of the number of plants that survived to maturity and plant height in the first treated generation and the mutation rate and mutant types in the second generation. The number of plants that survived to maturity after irradiation treatment was found to be greater and the mutation rate lower in the hexaploid variety Minhafer than in the diploid variety Saia. These were attributed to the reduplication of genes or chromosomes in the hexaploid. Although the difference was small, the mean reduction in plant height was evidently hugher in the hexaploid than in the diploid. This may be attributed to the presence of a proportion of plants with gross chromosomal aberrations that might be responsible for severe plant height reduction in the hexaploid. The better tolerance of the hexaploid to gross chromosomal aberrations was interpreted as due to the reduplication of chromosomes. Though not conclusively, the mutation spectra of the two ploids appeared to be not the same. The proportion for each of the mutant types recovered in one variety was strikingly different from that in the other. In Saia the most frequent mutations were albinos and light greens whi1e in Minhafer the most common types were light greens, bands, and stripes. No apparent difference between the effects of x rays and thermal neutrons on the reduction of plant height was observed. Thermal neutrons appeared to be more effective than x rays in producing mutations in both varieties at the same survival level. It was also found that more albinos in Saia and more bands in Minhafer were induced by thermal neutrons than by x rays. (auth)

• Research Organization: Univ. of Minnesota, St. Paul
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-010457
• OSTI ID: 4720860
• Journal Information: Radiation Botany, Journal Name: Radiation Botany Vol. Vol: 2
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BIOLOGY AND MEDICINE
CEREALS
CHROMOSOMES
GENETICS
MUTATIONS
OATS
QUANTITY RATIO
RADIATION EFFECTS
RADIATION INJURIES
THERMAL NEUTRONS
X RADIATION