2,4-D处理可刺激拟南芥抗生长素突变体(axr1-12)去雄后雌蕊的荚果发育(英文)

2,4-D Treatment Could Maintain the Development of Siliques from Emasculated Flowers of an Auxin-resistant Mutant axr1-12

axr1-12是20年前发现的抗生长素突变体,其荚果非正常发育的机制尚不明了。分别研究生长素(2,4-D)、赤霉素(GA3)和细胞分裂素(BAP)对去雄后axr1-12和野生型(Columbia)雌蕊发育的影响,结果表明,1μl(0.1nmol/花柱)的2,4-D处理可促使去雄后的axr1-12子房发育成荚果,而对Columbia荚果的发育起严重的抑制作用。与此同时,0.1nmol2,4-D处理还可促进去雄后axr1-12的胚珠发育成假胚。1μl(0.1～10.0nmol/花柱)的GA3处理对去雄的axr1-12和Columbia的荚果发育均有促进作用。而BAP仅对Columbia荚果有微弱的刺激作用。0.1nmol2,4-D和1.0nmol GA3配合处理去雄axr1-12雌蕊,对其荚果的伸长生长表现出了加性效应。由此可见,2,4-D可明显促进axr1-12荚果的单性生殖生长,GA3在此过程中也起着重要作用。

An auxin-resistant mutant axr1-12 was discovered twenty years ago, the mechanism of its abnormal silique development related to auxin signaling is still unclear. The effects of auxin （2,4-D）, gibberellin （GA3） and cytokinin （BAP） on emasculated flowers of axr1-12 and its wild type plant Columbia were comparatively studied. Silique development from emasculated flower of axr1-12 could be significantly stimulated with 1 μl of 2,4- D （0.1 nmol/pistil） while that of Columbia was severely inhibited. Additionally and interestingly, 2,4-D could also promote axr1-12 ovule developing into pseudo-seed. The silique elongation of emasculated flower in both axr1-12 and Columbia could be greatly stimulated with 1 μl of GA3 （0.1-10.0 nmol/pistil）. BAP only presented a very weak stimulation on Columbia＇ silique development. The application of 2,4-D （0.1 nmol/pistil） along with GA3 （1.0 nmol/ pistil） demonstrated an additive effect on the elongation of emasculated pistil in axr1-12. Taken together, our results suggest that 2,4-D obviously stimulated silique elongation through parthenogenesis in the mutant axr1-12 and GA3 was also important in this process.