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以克隆植物结缕草为研究对象,采用18 O作为示踪元素,从克隆植株不同生长发育阶段的复合节根系引入H218 O,在“异质高水”、“均质低水”两种环境条件下,探测和分析结缕草克隆植株复合节根、匍匐茎、A和B分株叶各构件组分系列内的水分生理整合格局特征及其生态效应。结果表明:(1)在两种水分环境条件下,H218 O在克隆植株主匍匐茎内各构件组分系列中均表现出双向传输的趋势,但更倾向于向顶传输。(2)H218 O向顶传输时,在“异质高水”生境内,基部复合节根系吸收的H218 O呈先增加后降低的趋势,而中部复合节根系吸收的H218 O呈先降低后增加的趋势;在“均质低水”生境内,中部复合节根系吸收的H218 O呈持续增加趋势。(3)在两种生境的3种引入情况下,H218 O均向顶传输到尖端生长点。其中在“异质高水”和“均质低水”生境内H218 O在克隆植株中向基传输过程中,传输强度整体上呈下降趋势;H218 O在主匍匐茎中传输时18 O分配于分株叶片中的量较多;H218 O在二级匍匐茎中的传输都呈现出明显的向顶趋势,传输距离都到达了二级匍匐茎的顶端生长点。(4)在绝大多数情况下,A分株叶系列的18 O丰度均明显高于B分株叶系列,这与A、B分株系列的生长发育特征相一致;但在“异质高水”生境内,中部分株吸收的H218 O在二级匍匐茎中传输时,分配于B分株叶系列的18 O明显高于A分株叶系列,即A分株系列相对于B分株系列的比较优势并不是一成不变的,在某些情况下还可以发生逆转。
Taking the plant Zoysiagrass as the research object, 18 O was used as the tracer element to introduce H218 O from the root segments of the composite plants at different growth and development stages of the cloned plants, Under the two environmental conditions, the physiological and biochemical patterns of the water physiological patterns and their ecological effects in the roots, stolons and leaves of A and B ramets were detected and analyzed. The results showed that: (1) Under the two water environmental conditions, H218 O showed a bi-directional transmission trend in all component components of the main stolons of cloned plants, but the translocation toward the top was more likely. (2) In the “heterogeneous high-water” habitat, H218 O absorbed by roots of root complex firstly increased and then decreased when H218 O was transferred to the top, while H218 O absorbed by roots of the middle compound root decreased first In the “homogeneous low water” habitat, the H218 O absorbed by the roots of the Central Composite Roots continued to increase. (3) In the three kinds of habitats introduced in both habitats, H218 O is transported to the top of the growing point. In the “heterogeneous high water” and “homogeneous low water” habitat, the transmission intensity of H218 O in the clonal plant was decreased in general. The transmission of H218 O in the main stolons O was more distributed in the leaves of ramets. The transmission of H218 O in the secondary stolons showed a significant upward trend, and the transmission distance reached the top growth point of secondary stolons. (4) In the vast majority of cases, the abundances of 18 O in leaves of A ramets were significantly higher than those in B ramets, which was consistent with the growth characteristics of ramets A and B; however, When the H218 O absorbed by middle strain in the high-quality water-high habitat was transferred in the secondary stolon, the 18 O distributed in the leaf series B was significantly higher than that in the A leaf series, The comparative advantages of the ramet series are not static and can in some cases also be reversed.