TITLE:
Insights into Seasonal Dormancy of Perennial Herbaceous Forages
AUTHORS:
Laxman Adhikari, Rasyidah M. Razar, Dev Paudel, Ruyue Ding, Ali M. Missaoui
KEYWORDS:
Herbaceous Perennials, Seasonal Dormancy, Genes, Endodormancy, Forages, Hormones
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.8 No.11,
October
16,
2017
ABSTRACT: Seasonal dormancy is an adaptive mechanism where plants suspend growth
and become physiologically inactive to avoid extreme environmental conditions.
Environmental factors like temperature, photoperiod, nutrients, and soil
moisture control plant growth and development through various complex molecular
mechanisms. Crown and seed dormancy of plants are mostly influenced by day
length and temperature. Genes and physiological pathways triggered by these two
factors along with genotype variability are some targets to manipulate seasonal
dormancy. There is genetic variation in the depth and duration of seasonal
dormancy. Therefore, their genetic manipulation is possible. Manipulations of
summer and fall dormancy are relatively easier compared to winter dormancy
because plants require protection of their apical meristem from freezing
temperatures and limited water supply. Genetic factors that regulate seed
dormancy may also have regulatory role for seasonal dormancy of the maternal
plants. Limited genetic and genomic information are available for seasonal
dormancy in herbaceous perennial species. Knowledge of genes controlling
seasonal dormancy of eudicots, forest trees, and horticultural crops could be
interpolated to explore possible dormancy mechanisms in perennial forages. This
study reviews current knowledge of seasonal dormancy of herbaceous forages
emphasizing the genetic and physiological context that would be valuable to
breeders and plant biologists to expand the production season of perennial
species by developing non-dormant and semi-dormant cultivars.