Cytological consequences of proembryo irradiation

Factors Responsible for Changes in Radiosensitivity of Embryonic Tissues. Technical Progress Report, 1969-1970

“…In the intact plant, buds are continually initiated throughout the five or more months of floral activity. As many as 140 or more flowers may be produced by a cluster which never contains at any one time more than 17 buds in each of its two "cymes" (Mericle and Mericle, 1966b). This continuation of bud initiation over long periods of time is in contrast to the general "blooming-out" of preformed buds only, so often seen following , -2 -irradiation of unrooted Tradescantia cuttings (Sparrow and co-workers, unpublished).…”

“…When senescence of the inflorescence finally does occur, it is not due to termination of bud initiation. Even though the rate of new bud formation does decline with cluster age (Mericle and Mericle, 1966b), at the time of last anthesis as many as five or more incompletely developed buds per "cyme" may still remain.…”

“…7,8 of Mericle and Mericle (1966b), even though both bud number and flowering interval undergo large changes during aging of the inflorescence, the length of the bud cycle remains nearly constant. Age associated differences in the time of appearance of the various developmental stages within the cycle can, however, help to explain the mutation rate differences observed in clusters of different ages (Mericle and Mericle, 1966b).…”

“…In the 02 clone of Tradescantia other factors such as inflorescence age can apparently also play contributory roles (Mericle and Mericle, 1965a, 1965b, 1966a, 1966b.…”

“…The occurrence of somatic color mutations in the flowers of the hybrid Tradescantia 02 clone has been or is being used in several studies other than this one, as a sensitive indicator of radiation level Mericle, 1965a, 1965b) and to measure the modifying influence of and interactions with other environmental components (Mericle and Mericle, 1965b, 1966a, 1966bSparrow, 1966). Relatively little is known, however, concerning the real nature of the changes involved in the production of a red mutant cell(s) amidst the normal bluish-purple cells comprising the petals and stamen hairs of the hybrid.…”