3份典型菊属野生种耐盐性及其解剖结构比较

Salt-tolerance and Anatomical Features of Three Typical Chrysanthemum Species

以野菊、甘菊、菊花脑幼苗为试验材料,用含360 mmol·L^(-1)NaCl溶液的Hoagland营养液进行胁迫处理,观察记录形态变化,分别于0(对照)、3、6、9 d取材测定相关生理指标,同时分别取0、6 d的叶片制作石蜡切片,观察并测量相关解剖结构特征。结果显示:3份材料在胁迫6 d时出现明显的表型差异,9 d时甘菊与菊花脑几全株死亡;叶片细胞质膜透性、脯氨酸质量分数及丙二醛质量摩尔浓度均随胁迫时间增加而增大,叶绿素质量分数则相反;叶片上下表皮厚度、栅栏组织厚度、海绵组织厚度、叶片厚度与中柱鞘直径均小于对照,仅野菊的栅栏组织厚度有所增加,且叶肉中央形成较大的通气组织,而甘菊与菊花脑在胁迫6 d时海绵组织结构模糊,叶肉细胞裂解严重,与表皮逐渐脱离。总之,3份菊属野生种材料均不宜在高浓度盐环境中生存,但野菊对盐环境有一定的适应能力;叶片质膜透性、光合指数与表皮细胞、叶肉细胞特征相关性较大。

In order to reveal the relative of morphological, physiological and anatomical characteristics in Chrysanthemum on sa- linity, we studied salt-tolerance and the anatomical features of its three typical species. C. indicum, C. lavandulifolium and C. nankingense were exposed to 360 mmol · L-1 NaC1 mixed with Hoagland for 9 days. Physiological parameters were deter- mined at 0 （CK） , 3, 6, 9 d, respectively. We measured anatomical variables of 0 and 6 d stressed plants. With the in- creasing of the stressed period, leaves membrane permeability, proline contents and MDA contents were increased, but the chlorophyll contents were the opposite. Compared to the control, thickness of epidermis, palisade mesophyll, spongy meso- phyll and leaves as well as the diameter of mid-vein were mostly reduced in certain extent. However, there was a slightly increase of palisade mesophyll in C. indicum as well as development of aeration tissue. Besides, C. lavandulifolium and C. nankingense were coUapsed in mesophyll cell and separated from epidermis under 6-day stress. Therefore, three species were not tolerant to high salinity, C. indicum showed some adaptive ability to short-term stressed though, and the leaves membrane properties and photosynthesis characteristics were better related with features of the epidermis and mesophyll tis-sues.