the Role of the photoperiod and temperature in growth regulation. Development of genitals

you are: the Role of the photoperiod and temperature in growth regulation

At some plants under the photoperiodic control is not only itself initsiatsija flowerings, but also development of separate genitals. It is most brightly expressed at the plants forming stamens and pestles in different tsvetkah - on separate plants (dvudomnye) or on the same plant {odnodomnye). Usually photoperiodic conditions accelerating initsiatsiju flowerings, promote display of female signs and suppression of the man's. at dvudomnogo korotkodnevnogo hop plants (Humulus) at tsvetkov, intended to become man's, at a short bottom there are female signs: on man's pylnike are formed ryltsevye tops (a female sign) so stamens are similar to pestles. At korotkodnevnyh plants (Xanthium) which influenced only one short day before carrying over to not inducing conditions of long day, it is formed more tychinochnyh, than pestichnyh, tsvetkov, and at continuous cultivation in the conditions of short day the return parity turns out.

Floor Display can be changed also by means of temperature influence or introduction of hormones. This sort of worth-while experiments have been spent on pumpkin, such as cucumbers, a pumpkin and gherkins (Cucumis anguria).

Usually these odnodomnye form plants man's tsvetki on the bottom knots, and female - on top (fig. 12.19). However long days and heats can cause transformation of some potentially female knots in man's, and short days and low temperatures cause a boomerang effect. Long day it is possible to replace with introduction gibberellovoj acids; it could be expected, as under the influence of long day level endogennogo gibberellina usually increases. Auksin, etilen and abstsizovaja acid promote display of female signs, and endogennye levels of these hormones usually increase at a short bottom. thus, the floor, possibly, is supervised by interactions of the several hormones which maintenance in turn depends on length of day. Most strongly operates auksin: flower kidneys, on the arrangement intended to become man's, can develop as female if them to separate and grow up on the Wednesday containing IUK. The so sharply expressed plasticity in floor display is unusual.