三粒小麦额外雌蕊的分化

Differentiation of Additional Pistils in A Trigrain Wheat

The differentiation process of florets and the three pistils of a trigrainwheat is investigated with a scanning electronic microscope and paraffinsection method.It is observed that the differentiation process of florets ina trigrain wheat is just the same as in common wheat,but after the formationof lodicules and primordia of stamen and pistil,floret differentiation doesnot stop and other two additional pistils are gradually formed by periclinaldivision of sub-hypodermal cell in the axil of lodicules.The productivemanner of the additional pistils which differentiate at the latest in floret,is analogous to that of a bud.According to their origin,the additional pistils are not only differentfrom the primary pistil,which comes from meristem tissue at the top of thefloret,but also without carpellody in constitution.Though the additionalpistils occur late,they develop quickly after style-formation so that theyachieve maturity and get normal fertility as the primary pistil does duringthe blooming.