The leaf chlorosis in the wheat genotype AIM9 was demonstrated to be controlled by a single recessive gene, which was designated as CD5. Significant difference in physiological and yield indices between chlorotic and non-chlorotic plants were observed in 10 F3segregating families of the cross combination CN17/AIM9. Correlation analysis of both chlorotic plants and plants staying green of the F3 populations revealed that there was a significant positive correlation between yield index values and the physiological indices net photosynthetic rate (Pn), stomatal conductance (Gs), and chlorophyll (Chl), as well as a significant negative correlation between yield index values and the physiological indices intercellular CO2 concentration (Ci) and malondialdehyde (MDA). Observation using transmission electron microscopy (TEM) found the irreversible centripetal movement of chloroplasts in chlorotic plants, as a result occurred in three sequential events: (1) chloroplast positions changed from face position (with long axis of chloroplasts at the cell walls perpendicular to light ray) to profile position (with long axis chloroplasts near the cell walls parallel to light ray), (2) chloroplast shapes changed from long elliptical to circular, (3) chloroplasts were separated from the cell wall and moved to the center of the cell.%小麦材料AIM9的叶片失绿表现型是受一对隐性单基因控制的,该基因暂命名为CD5.在10个源于杂交组合CN17/AIM9的F3分离家系中失绿植株和对照植株在许多生理指标和收获指标上呈现显著差异.相关性分析表明收获指标与生理指标,如净光合速率、气孔导度、叶绿素含量等呈显著正相关;而与细胞间CO2浓度及丙二醛含量呈显著负相关.透射电镜观察发现失绿叶片中的叶绿体发生不可逆的向心运动,整个过程大致经历以下几个阶段:(1)叶绿体从叶绿体长轴垂直于光线转变至叶绿体长轴平行于光线;(2)叶绿体的形状从椭圆形转变为圆形;(3)叶绿体脱离细胞壁向细胞中心运动.
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