Pompelli M F, Martins S C V, Celin E F, Ventrella M C, Damatta F M
Departamento de Botânica, Centro de Ciências Biológicas, Universidade Federal de Pernambuco, Recife, PE, Brazil.
Braz J Biol. 2010 Nov;70(4):1083-8. doi: 10.1590/s1519-69842010000500025.
Stomata are crucial in land plant productivity and survival. In general, with lower irradiance, stomatal and epidermal cell frequency per unit leaf area decreases, whereas guard-cell length or width increases. Nevertheless, the stomatal index is accepted as remaining constant. The aim of this paper to study the influence of ordinary epidermal cells and stomata on leaf plasticity and the influence of these characteristics on stomata density, index, and sizes, in the total number of stomata, as well as the detailed distribution of stomata on a leaf blade. As a result, a highly significant positive correlation (R²(a) = 0.767 p ≤ 0.001) between stomatal index and stomatal density, and with ordinary epidermal cell density (R²(a) = 0.500 p ≤ 0.05), and a highly negative correlation between stomatal index and ordinary epidermal cell area (R²(a) = -0.571 p ≤ 0.001), were obtained. However in no instance was the correlation between stomatal index or stomatal density and stomatal dimensions taken into consideration. The study also indicated that in coffee, the stomatal index was 19.09% in shaded leaves and 20.08% in full-sun leaves. In this sense, variations in the stomatal index by irradiance, its causes and the consequences on plant physiology were discussed.
气孔对于陆地植物的生产力和生存至关重要。一般来说，随着光照强度降低，单位叶面积的气孔和表皮细胞频率会下降，而保卫细胞的长度或宽度会增加。然而，气孔指数被认为保持不变。本文旨在研究普通表皮细胞和气孔对叶片可塑性的影响，以及这些特征对气孔密度、指数、大小、气孔总数以及叶片上气孔详细分布的影响。结果发现，气孔指数与气孔密度之间存在极显著的正相关（R²(a) = 0.767，p ≤ 0.001），与普通表皮细胞密度也存在正相关（R²(a) = 0.500，p ≤ 0.05），而气孔指数与普通表皮细胞面积之间存在极显著的负相关（R²(a) = -0.571，p ≤ 0.001）。然而，在任何情况下都未考虑气孔指数或气孔密度与气孔尺寸之间的相关性。该研究还表明，在咖啡中，遮荫叶片的气孔指数为19.09%，全日照叶片的气孔指数为20.08%。从这个意义上讲，讨论了光照强度引起的气孔指数变化及其对植物生理学的影响。
