干旱胁迫对小麦中国春-Synthetic 6x代换系叶片超微结构的影响

Effect of drought stress on ultrastructure of flag leaves in wheat chromosome substitution lines

观察比较了干旱胁迫下两个小麦代换系品种及其亲本旗叶超微结构的差异,结果表明:在正常灌水条件下,父本Synthetic 6x、母本中国春以及2D、5D代换系旗叶叶肉细胞中叶绿体、细胞核、线粒体结构正常。干旱胁迫条件下,抗旱性较强的父本Synthetic 6x与2D代换系变化较小,叶绿体稍显膨胀,基粒片层较发达,淀粉粒较多;细胞核与线粒体无明显变化。而抗旱性较弱的母本中国春与5D代换系变化明显,叶绿体膨胀成球形,类囊体肿胀,基质片层模糊,脂类小滴增加,淀粉粒数量减少,部分叶绿体开始解体;线粒体部分外膜断裂,嵴结构模糊不清;细胞核无明显变化。叶肉细胞变化程度与小麦的抗旱性呈负相关。

The differences of cell ultra-structure of flags leaves in two wheat substitution lines and parents under drought stress were investigated. The result showed that the ultra-structure of the chloroplasts and nucleus as well as mitochondria of 2D and 5D substitution lines along with parents were alike under normal irrigation. The cell ultra-structure of flags leaves of 2D substitution line and Synthetic 6x with strong drought resistant were less affected than 5D substitution line and Chinese Spring with weak drought resistant under drought stress. The chloroplast with a few starch grains and plentiful grana lamellae of 2D substitution line and Synthetic 6x became a little swelling, whether the nucleus and mitochondria showed no obvious change. The chloroplasts of 5D substitution line and Chinese Spring became more round, thylakoid of chloroplast became swollen, matrix lamella became obscure, the number of lipid body balls increased, the starch grains decreased, a few chloroplast began to disintegrate ; Part of envelope of mitochondria with indistinct cristae began to breakage, the nucleus also showed no obvious change. The changes of flag leaves were negative correlation with wheat drought-resistant.