
The
transition to flowering is one of the major phase changes that a plant
makes during its life cycle. The transition must take place at a time
that is favorable for fertilization and the formation of seeds, hence
ensuring maximal reproductive success. To meet these needs a plant is
able to interpret important endogenous and environmental cues such as
changes in levels of plant hormones and seasonable temperature and
photoperiod changes.[3] Many perennial and most biennial plants require
vernalization to flower. The molecular interpretation of these signals
is through the transmission of a complex signal known as florigen, which
involves a variety of genes, including CONSTANS, FLOWERING LOCUS C and
FLOWERING LOCUS T. Florigen is produced in the leaves in reproductively
favorable conditions and acts in buds and growing tips to induce a
number of different physiological and morphological changes.[4] The
first step is the transformation of the vegetative stem primordia into
floral primordia. This occurs as biochemical changes take place to
change cellular differentiation of leaf, bud and stem tissues into
tissue that will grow into the reproductive organs. Growth of the
central part of the stem tip stops or flattens out and the sides develop
protuberances in a whorled or spiral fashion around the outside of the
stem end. These protuberances develop into the sepals, petals, stamens,
and carpels. Once this process begins, in most plants, it cannot be
reversed and the stems develop flowers, even if the initial start of the
flower formation event was dependent of some environmental cue.[5] Once
the process begin
No comments:
Post a Comment