瓠瓜离体潜在雌花芽性别分化的激素控制

HORMONAL CONTROL OF SEX DIFFERENTIATION OF POTENTIALLY FEMALE FLORAL BUDS OF LAGENARIA SICERARIA VAR. HISPIDA IN VITRO

在离体条件下,硫代硫酸银（STS）和GA,也能有效地改变瓠瓜（Lagenaria siceraria var.hispida）的潜在雌花芽性别分化的方向。在含有IAA、BA和ACC（1-氨基环丙烷-1-羧酸）各为1nmol/L的MS培养基中,添加GA3（1-500μmol/L）可以诱导瓠瓜侧芽上的潜在雌花芽发育成为雄花,其中以5—20μmol/L GA,的效果最明显。与GA3相比,STS诱导雄花的效果又比GA3的大,尤其以STS的浓度为100—500μmol/L时效果最佳。相反,当上述的IAA和ACC浓度不变,而BA浓度提高到100μmol/L,再添加10—50nmol/L GA3时,则有利于潜在雌花芽向原来方向即雌花方向分化。这说明潜在雌花芽的进一步分化也需要一定浓度的GA,和比较高浓度的BA（100nmol/L）。

In the present study, several kinds of phytohormones were used for the control of sex differentiation of the potentially female floral buds of Lagenaria siceraria var. hispida in vitro. It was shown that both GA_3 and STS (silver thiosulphate) could effectively change the direction of sex differentiation of the potentially female floral buds in vitro. In the MS medium, supplemented with IAA, BA and ACC(1-aminocyclopropane-1-carboxylic acid) at 1 nmol/L, male flowers would be induced from the potentially female floral buds by the addition of GA_3 (1—500μmol/L). Herein the male flowers were induced more effectively by GA_3 within 5—20 μmol/L but it was not as effective as STS. In the MS medium supplemented with IAA, BA and ACC at 1 nmol/L and with GA_3 at 20 nmol/L more male flowers were differentiated from the potentially female floral buds with the addition of STS within 100—500 μmol/L. On the contrary, when the MS medium were supplemented with IAA and ACC at 1 nmol/L and with BA increased to 100 nmol/L more female flowers were differentiated from the potentially female floral buds, even with addition of 10—50 nmol/L of GA_3.