【摘要】 将含有抗溴苯腈基因bxn和雄性不育基因的重组载体pTA29-Barnase/bxn导入农杆菌(Agrobacterium tumefaciens)后转化烟草(Nicotiana tabacum L.),得到33个转基因植株。在27℃/23℃培养的16株中,有7株表现部分不育,另9株全部可育。而在20℃/15℃培养的17株中,12株表现不育,5株表现部分不育。部分不育的植株上同时开放可育花朵和不育花朵,不过其中的不育花朵中的花粉萌发活力很低。将在20℃/15℃条件下表现不育的12个不育株从20℃/15℃温室移至27℃/23℃温室后30d左右,其中9株表现程度不同的育性恢复现象:5株表现部分可育,另4株表现完全可育;但仍有3株表现雄性不育。雄性不育花朵的花丝变短,花药皱瘪,不散粉。细胞学观察证明,转基因植株的花药绒毡层降解提早于四分体时期,至单核小孢子时期降解殆尽。更多还原

【Abstract】 A chimeric gene TA29-Barnase/bxn was transformed into tobacco (Nicotiana tabacum L.) plants. This gene confers on transgenic plants male sterility feature and resistance to the herbicide-bromoxynil. The resistance to the herbicide was used as a dominant marker for the male sterility trait in agricultural application. Seven of the sixteen transgenic bromoxynil-resistant plants were partially male sterile at the greenhouse temperature of 27C/23C, and the others were male fertile. However twelve of the seventeen transgenic bromoxynil-resistant plants were male sterile at 20C/15C in the greenhouse, and the other five bearing male sterile flowers and fertile flowers were partially male sterile. As the temperature reached 27C or higher, four of the twelve male sterile plants restored their fertility in respect to their morphology and cytology of the new flowers in about one month, and 5 transgenic plants showed partially male sterile and the other 3 transgenic plants remained male sterile. The most prominent morphological change in the male sterile plants was a noticeable shortening of their stamen-filaments and absence of pollen. Cytological abnormality exhibited destruction of tapetal cell layer as early as from the stage of tetrad to the free uninuclear microspore during which the normal tapetum was not observed. The male sterile anthers contained no pollen grains, and the male sterile flowers failed to self-pollinate,then fell off.更多还原