Improving prodn. of seeds for growing hybrid rice - using mixt. of pre-germinated and dry male seeds, adjusting onset of male plant

摘要

Prodn. of seeds for growing hybrid rice is improved by (1) sowing the male parent seed as a mixt. of 75-25 wt.% pre-germinated seed and 25-75 wt.% dry seed. Pref. process also includes adjusting the onset of heading of the male plant either by draining water from the growing area (if male heading is more advanced than female heading) or by flooding the growing area by raising the water level (if male heading is less advanced than female heading); and/or spraying the female plants with a warm soln. of gibberellin (pref. GA3) at the time the flower begins to emerge from its leaf sheath, the soln. having a temp. of 34-38 (pref. 35-36)deg.C. In method (1), the number of days during which the pollen of the male plant is available is extended; in method (2), synchronisation of heading between male and female plants can be controlled; and in method (3), improved pollination of the female plant is achieved.