【摘要】 为了解小麦基部小穗不孕突变体的农艺性状和小穗形态发育特点,对EMS诱变小麦品系山农1186所得的基部小穗不孕突变体进行了农艺性状鉴定和小穗发育过程观察。结果表明,10个突变株系基部有2~4个不孕小穗,而山农1186基部小穗正常结实;与受体山农1186相比,10个突变株系的穗长、小穗数没有变化,但穗粒数显著降低,降低幅度为20.63%~44.44%;突变株系的株高、穗下节、倒二节、倒四节、倒五节间长度显著增加,平均增长27.28%、20.55%、22.58%、51.10%和93.55%,倒三节间长度增加不显著,表明株高的增加是由多个节间伸长造成的;大多数株系的旗叶、倒二叶、倒三叶长度增加不显著,但宽度显著变窄,分别比对照平均减少16.93%、18.15%和14.36%,叶长、叶宽的变异并未引起叶面积的明显变化。对小穗发育的形态学观察发现,突变体基部小穗在四分体时期开始退化,雌蕊、雄蕊、子房萎焉失水,变成模糊的一团组织,进而导致基部小穗不孕。更多还原

【Abstract】 Using 10 distal spikelets sterility mutant lines which were obtained from the EMS induced Shannong1186,the agronomic traits were identified and spikelet development was observed.The investigation on agronomic traits showed that 2~4 distal spikelets of all the 10 mutant lines were sterile.However,the distal spikelets of Shannong1186 were fertile.Compared with Shannong1186,grains per spike of all the 10 mutant lines decreased significantly,which ranged from 20.63% to 44.44%,but spike length and spikelets per spike had no significant change.Plant height,length of the first,second,fourth and fifth node from top of all the mutant lines significantly increased 27.28%,20.55%,22.58%,51.10% and 93.55%,respectively.There were no significant difference for length of the third node from top between the mutant lines and Shannong1186.It indicated that the increased length of nodes led to increase of plant height.The increase of length of flag leaf,penultimate leaf and the third leaf from top for the most mutant lines were not significant,but the width of them significantly decreased 16.93%,18.15% and 14.36%,respectively.The variation of length and width of leaves had not caused difference in leat area of them.Observation on spikelet morphological development showed that distal spikelets of the mutant began to degrade in tetrad stage.Pistils,stamens and ovaries of mutants became wilt and turn to illegibile organism.Degeneration was the reason why distal spikelets of mutants were sterility as distal spikelets of Shannong1186 could develop normally in tetrad stage.更多还原