渍涝对不同耐性花生品种根系形态特征及解剖结构的影响

为解析渍涝对花生根系形态特征的影响，以耐性品种湘花2008与敏感品种中花4号根系为研究材料，在自制根架系统内进行盆栽培养，于幼苗期分别进行0、3、6、9、12 d渍涝胁迫处理，通过根系的鲜（干）重以及显微和超微结构研究不同耐性花生品种根系形态特征的差异。结果表明，渍涝胁迫下中花4号根系受影响较大，随着淹水天数延长，根系颜色加深，臭味加重，而湘花2008仅根系中、上部根色变黄，臭味较轻，湘花2008根系鲜重耐渍系数高于中花4号。湘花2008出现了通气组织，且随着淹水时间增加，通气组织数量增加、横截面积加大；主根中段木质部基本保持正常，导管大体呈射线状分布。而中花4号未形成明显的通气组织，木质部和导管呈不规则分布。湘花2008主根细胞内的细胞核、线粒体虽受到影响，但仍能维持细胞活动，保持根系生长状态。中花4号细胞器受渍涝胁迫较敏感，加速衰老死亡。综上认为，渍涝胁迫下湘花2008根色和根味受影响较小，主根出现了通气组织，主根中段木质部与细胞中的细胞核、线粒体基本正常。而中花4号根色和根味受影响较重，未形成明显的通气组织，主根中段木质部和导管呈不规则分布，主根中段细胞中的细胞质溶解，线粒体异常。本研究可为解析花生耐渍涝机理提供依据。

Effects of waterlogging stress on root morphological characteristics and anatomical structure of peanut varieties with different tolerance

In order to analyze the influence of waterlogging on the morphological characteristics of peanut root system, a tolerant variety Xianghua 2008 and a sensitive variety Zhonghua 4 were used as materials, and pot experiment was carried out with the self-made root rack system. After 0, 3, 6, 9, and 12 days of waterlogging stresses in the seedling stage, the root morphological characteristics were studied based on the fresh （dry） weight, microscopic and ultrastructure of the root system. The results showed that the root system of Zhonghua 4 was greatly damaged by waterlogging stress. As the days of flooding prolonged, the root color of Zhonghua 4 became darker and smelled bad, while, for Xianghua 2008, only the middle-and-upper roots was slightly yellow and lighter odor. Waterlogging tolerance cofficient of fresh weight of the root system was higher than that of Zhonghua 4. In addition, aerenchyma appeared in Xianghua 2008, the number and cross-sectionalarea of aerenchyma increased with flooding time. Xylem of the middle section of the main root remained basically normal, and the ducts were generally distributed in rays. On the contrary, no obvious aerenchyma was formed in roots of Zhonghua 4, and the xylem and ducts were irregularly distributed. Although the nucleus and mitochondria in the main root cells of Xianghua 2008 are affected, they could still maintain cell activity and root growth. The organelles of Zhonghua 4 were more sensitive to waterlogging stress and accelerate senescence and death. In summary, the root of Xianghua 2008 were less affected under waterlogging stress, aerenchyma appeared in the main root, the xylem and the nucleus and mitochondria in cells in the middle of the main root were basically normal. However, the roots of Zhonghua 4 were severely damaged, and no obvious aerenchyma was formed. The xylem and ducts in the middle of the main root were irregularly distributed, the cytoplasm of the cells in the middle of the main root was dissolved, and the mitochondria were abnormal. This study could provide a basis for analyzing the waterlogging resistance mechanism of peanut.