外源BoCAL基因对花椰菜花球形态发生的调节及其遗传

花椰菜和结球甘蓝是芸薹属甘蓝种的两个变种,前者的BobCAL基因发生提前终止突变而失去了原有的功能,而后者的BoCAL基因具有完整的编码区。在农杆菌的介导下,我们获得了BoCAL转基因花椰菜。T_2代的遗传研究表明,外源BoCAL基因转入后花椰菜转基因植株都没有形成花球,而是只形成松散的由花蕾组成的绿色花序。这一结果说明,花椰菜BobCAL被甘蓝BoCAL互补了,转基因花椰菜因此失去了形成花球的能力。这些转基因植株自交到T_3代时花序的形态特征与T_2代一致,为松散的绿色花序,但是花序出现的时间与T_1代相比提早了15天。将转基因花椰菜与野生型花椰菜杂交,结果发现杂交后代的植株形成夹杂有花蕾的花球,且花序出现的时间大大推迟,在播种后135天后才形成花球。

REGULATION TO CURD MORPHOGENESIS AND GENETICS OF EXOGENOUS BoCAL GENE IN CAULIFLOWER

r Cauliflower (Brassica oleracea var. botrytis L. ) and cabbage (B. oleracea var capi-tata L. ) are two varieties of species B. oleracea . Cauliflower BobCAL gene losses the original function due to its terminated mutation while cabbage BoCAL gene has the complete function. We obtained cauliflower plants transgenic for BoCAL gene using Arobacterium-mediated transformation. Genetic analysis of T2 generation indicated that all cauliflower plants transgenic for BoCAL failed to form curd and produced the green, loosed inflorescences composed of flower buds instead, demonstrating that cauliflower BobCAL was complemented by cabbage BoCAL , and thus transgenic cauliflower lost the a-bility to form curd. Selfing of these transgenic plants gave rise to the similar inflorescence phenotype of T3 plants except 15 days delay of inflorescence appearance compared with the plants of T1 generation. When transgenic cauliflower was crossed with wild-type cauliflower, the progenies formed the curd with a few of flower buds, and they delayed inflorescence onset till 135 days after sowing.