淹水胁迫对两种栎树生长的影响

Influences of Waterlogging Stress on the Growth and Leaf Anatomical Structures of Two Oak Species

对纳塔栎、南方红栎的2 a生苗在深度淹水约20 cm、浅度淹水(完全水饱和)、对照3种水平下持续76 d的生长进行研究,其中又以抗涝性极强的落羽杉作为参照。主要测定了各树种的生物量和株高,并对外部形态特征及叶片内部解剖结构的变化进行了观察。结果表明:浅淹没有造成苗木死亡,深度淹水第49天南方红栎开始出现枯死植株,第76天纳塔栎出现轻微受害症状,落羽杉没有出现受害症状。与各自对照相比,浅淹水平对落羽杉、纳塔栎的高生长及生物量的累积均具有促进作用,且对落羽杉影响较显著,而对南方红栎影响不显著;深淹水平对落羽杉、纳塔栎的高生长及生物量的累积影响不显著,但对南方红栎具有显著的抑制作用。同时,发现淹水对落羽杉、纳塔栎的叶片解剖性状影响不显著,而深淹水平下,数据显示南方红栎的叶片内部细胞间隙明显增大。综合表明两种栎树都具有较强的耐水性,而纳塔栎更优于南方红栎,仅次于落羽杉。

The two-year-old Quercus nuttallii and Quercus Shumavdii B. seedlings were planted in three treatments of deep （20cm） waterlogging, shallow （saturated water conten） waterlogging and no waterlogging for 76 days to study the influences of waterlogging stress on their growth and leaf anatomical structures. Taxodiaceae taxodium L was selected as the control species with the same treatments. Biomass and the height of seedlings were measured, and external morphological characters and anatomic structures in leaves were observed. The results showed that there was no death seedling of two oak species in the condition of shallow waterlogging stress, while under deep waterlogging stress Q. Shttmavdii seedlings began to die after 49 days, Q. nuttallii seedlings was lightly harmed after 76 days, and no any damaged symptoms were observed in the T. taxodium seedlings. Compared with the control, shallow waterlogging stress could improve biomass accumulation and the height of Q. nuttallii and T. taxodium, especially for the former. Under deep waterlogging stress, the height and biomass of Q. Shumavdii seedling was suppressed obviously, while for Q. muttallii and T. taxodium seedlings the effects were not obvious. Waterlogging stress had no obviously influences on the anatomical structures in leaves of T. taxodium and Q. nuttallii, while the intercellular spaces in leaves of Q. Shttmavdii were greater than the control. Synthetically, waterlogging-tolerance of two oak species was stronger, and comparatively, Q. nuttallii was stronger than Q. Shumavdii and weaker than T. taxodt＇um in waterlogging-tolerance.