THE EFFECT OF IRRADIATION ON SPOROGENESIS, GAMETOPHYTE DEVELOPMENT AND SEED SET IN YELLOW-ANTHERED DALLISGRASS
A study was initiated to evaluate the effects of irradiation on selected clones of yellow-anthered dallisgrass. The studies were planned to determine the effects of radiation on microsporogenesis, megasporogenesis, and embryo sac development and to relate the effects on gametogenesis to fertility as indicated by seed set and pollen quality. It was indicated in these studies that any aberrations in the chromosomes caused by irradiation were detrimental to both the megagametophyte and the microgametophyte. It was apparent that there was no selectivity for a balanced megaspore within the tetrad of megaspores. In all cases only the chalazal megaspore was functional. Damage to the female gametophyte may be definitely more severe as a factor in fertility, since only the single chalazal megaspore is potentially functional in this species while numerous microspores are produced. Neutron and gamma radiation affected both male and female gametophytes though not necessarily to the same extent. The results show that while irradiation at the levels studied generally reduces fertility, it is possible to produce significant desirable changes in growth characteristics without causing serious fertility problems. also, it was apparent that irradiation causes reduction in fertility that cannot be explained on the basis of visible chromosome aberrations. These results indicate that a large population of plants are needed if a breeder is to have reasonable success in selecting desirable mutant plants that are fertile. (M.P.G.)
- Research Organization:
- Originating Research Org. not identified
- NSA Number:
- NSA-18-008193
- OSTI ID:
- 4132175
- Resource Relation:
- Other Information: Thesis. Orig. Receipt Date: 31-DEC-64
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
Similar Records
GENETIC STUDIES ON THE BEHAVIOR OF THE B$sup 3$ CHROMOSOME IN TB-3a, AND THE USE OF A-B TRANSLOCATIONS IN MUTATION STUDIES, IN MAIZE
EFFECT OF IONIZING RADIATION ON MICROSPOROGENESIS IN PINUS RIGIDA MILL