Herbivory could unlock mutations sequestered in stratified shoot apices of genetic mosaics
-
-
Authors: M. Marcotrigiano
Date: 2000
Journal: American Journal of Botany
Volume: 87
Number: 3
Pages: 355-361
Summary of Methods: In order to determine whether developmentally sequestered mutations could be released by herbivory (i.e., meristem destruction), a characterized genetic mosaic was subjected to simulated herbivory. Many plants develop two shoot meristems in the leaf axils of some nodes, here referred to as the primary and secondary axillary meristems. Destruction of the terminal and primary axillary meristems led to the outgrowth of secondary axillary meristems. Seed derived from secondary axillary meristems was not always descended from the second apical cell layer of the terminal shoot meristem as is expected for terminal and primary shoot meristems. Vegetative and reproductive analysis indicated that secondary meristems did not maintain the same order of cell layers present in the terminal shoot meristem. In secondary meristems reproductively sequestered cell layers possessing mutant cells can be repositioned into gamete-forming cell layers, thereby adding mutant genes into the gene pool. Herbivores feeding on shoot tips may influence plant evolution by causing the outgrowth of secondary axillary meristems.
Article Summary / Main Points: None
Vegetation Types:
MLRA Ecoregions:
Agrovoc Control Words: Riparian zones Rangelands Wildlife
Article Review Type: Refereed
Article Type: Experimental Research
Keywords: cell fate, herbivory, mutational loading, nicotiana sylvestris, periclinal chimeras, plant evolution
Annotation: Nicotiana sylvestris plants were grown in a greenhouse under 16 hour or longer days to promote flowering. The phenotype of seedlings derived from mosaic shoots was evaluated 10 days after the seed had germinated. Two treatments consisted of different levels of simulated herbivory. In treatment 1, the terminal shoot tip was manually destroyed to eliminate the terminal bud and the most dominant primary axillary shoot was allowed to grow and flower. In treatment 2, the terminal bud and all primary axillary buds were manually destroyed and the most dominant secondary axillary shoot was allowed to grow and flower. Season of use not specified.
-
Get article
Cite article with DOI
-