Departament de Biologia Vegetal, Facultat de Biologia, Universitat de Barcelona, 08028, Barcelona, Spain.
Photosynth Res. 1990 Oct;26(1):49-57. doi: 10.1007/BF00048976.
Several leaf anatomical and ultrastructural characteristics usually related with photosynthetic capacity were examined in two Flaveria species with strong differences in anatomy and their F1 hybrid. Flaveria trinervia (Spreng.) Mohr (C4) was the female parent and F. brownii A.M. Powell (C4-like) was the male parent. Quantitative anatomical analysis was made on transverse sections of leaves at both the light and electron microscope level. Four kinds of photosynthetic tissues were considered: bundle sheath (BS), mesophyll adjacent to the BS, mesophyll not adjacent to the BS, and larger spongy mesophyll cells. Flaveria trinvervia partitioned a larger proportion of its photosynthetic cells to BS and the mesophyll layer adjacent to BS and also possessed larger chloroplasts, especially in BS, than did F. brownii. These results suggest that although F. brownii is very C4-like, its anatomy is not as completely C4 as is the case for F. trinervia. In the F1 hybrid the relative contribution of the different tissues to the total photosynthetic tissue volume and area per unit leaf area was quite similar to that of F. trinervia. On the other hand, the chloroplast density and size of the F1 hybrid were fairly similar to those of F. brownii, especially in BS. Thus, there was no evidence of maternal inheritance in the chloroplast characteristics studied. A negative correlation (P<0.05) between chloroplast size and density was observed among species and relicates within each kind of tissue. This correlation was highest (r=-0.94, P<0.001) for the BS and when values were plotted on a logarithmic scale. Thus, higher chloroplast numbers for F. brownii and the F1 hybrid were offset by larger chloroplasts in F. trinervia. Less complete C4 photosynthesis in F. brownii may be partially due to incomplete development of Kranz anatomy usually associated with C4 photosynthesis.
两种具有强烈解剖差异的斑鸠菊属（Flaveria）物种及其 F1 杂种的几个叶片解剖和超微结构特征通常与光合作用能力有关，进行了检查。弗拉维尔亚·特林维西亚（Spreng.）Mohr（C4）为雌性亲本，弗拉维尔亚·布劳尼（A.M. Powell）（C4 样）为雄性亲本。在光镜和电子显微镜水平上对叶片的横切面进行了定量解剖分析。考虑了四种光合组织：鞘（BS）、与 BS 相邻的叶肉、与 BS 不相邻的叶肉和较大的海绵叶肉细胞。弗拉维尔亚·特林维西亚（Flaveria trinvervia）将更大比例的光合细胞分配给 BS 和与 BS 相邻的叶肉层，并且其叶绿体，尤其是 BS 中的叶绿体比弗拉维尔亚·布劳尼（Flaveria brownii）更大。这些结果表明，尽管弗拉维尔亚·布劳尼（Flaveria brownii）非常 C4 样，但它的解剖结构并不像弗拉维尔亚·特林维西亚（Flaveria trinervia）那样完全 C4。在 F1 杂种中，不同组织对总光合组织体积和单位叶面积的相对贡献与弗拉维尔亚·特林维西亚（Flaveria trinervia）非常相似。另一方面，F1 杂种的叶绿体密度和大小与弗拉维尔亚·布劳尼（Flaveria brownii）非常相似，尤其是在 BS 中。因此，在所研究的叶绿体特征中没有母体遗传的证据。在物种之间和每种组织内都观察到叶绿体大小和密度之间存在负相关（P<0.05）。这种相关性在 BS 中最高（r=-0.94，P<0.001），当以对数标度绘制时。因此，弗拉维尔亚·布劳尼（Flaveria brownii）和 F1 杂种的叶绿体数量较高被弗拉维尔亚·特林维西亚（Flaveria trinervia）中较大的叶绿体所抵消。弗拉维尔亚·布劳尼（Flaveria brownii）中不完全的 C4 光合作用可能部分是由于与 C4 光合作用通常相关的不完全的 Kranz 解剖结构的发育。
