Van der Sman A J M, Blom C W P M, Barendse G W M
Department of Ecology, University of Nijmegen, Toernooiveld, 6525 ED Nijmegen, The Netherlands.
New Phytol. 1993 Sep;125(1):73-84. doi: 10.1111/j.1469-8137.1993.tb03865.x.
The flooding resistance of Rumex maritimus L. and Rumex palustris Sm., two species from frequently flooded areas of river forelands, was studied in two large-scale outdoor experiments. Plants were raised in cohorts and in several stages of development subjected to four weeks of submergence in early summer or in midsummer. The role of under-water shoot elongation in raising foliage above the water line was not equally important in both species. In R. maritimus, survival following either early- or midsummer flooding was restricted mainly to plants which emerged from the water surface by elongating their main shoot. R. palustris was better able to survive submergence, especially under early-summer conditions. As a consequence of survival being restricted to plants in the stem elongation stage, flooded plants of R. maritimus all reproduced in the first growing season and seed output correlated positively with stem length immediately after flooding. This was also the case for R. palustris flooded at midsummer. However, for plants of R. palustris which were flooded in early summer and remained below the water line, flowering was delayed or even postponed to the following season. Variation in seed weight was much larger in R. maritimus than in R. palustris and more clearly related to cohort and treatment effects. Differences between both species in Hooding resistance did not seem to be primarily caused by different abilities of shoot elongation, but by differences in submergence tolerance in relation to life-history characteristics.
在两项大规模户外实验中，对来自河漫滩频繁被淹地区的两种植物——滨海酸模（Rumex maritimus L.）和沼生酸模（Rumex palustris Sm.）的抗淹性进行了研究。植株按批次培育，并在发育的几个阶段于初夏或仲夏遭受四周的淹水。水下茎伸长在将叶片提升至水线以上方面所起的作用，在这两个物种中并非同等重要。在滨海酸模中，初夏或仲夏淹水后的存活主要限于那些通过伸长主茎从水面露出的植株。沼生酸模更能耐受淹水，尤其是在初夏条件下。由于存活限于处于茎伸长阶段的植株，滨海酸模的淹水植株在第一个生长季均能繁殖，种子产量与淹水后立即测量的茎长度呈正相关。仲夏淹水的沼生酸模也是如此。然而，对于初夏淹水且仍处于水线以下的沼生酸模植株，开花延迟甚至推迟到下一季。滨海酸模种子重量的变异比沼生酸模大得多，且更明显地与批次和处理效应相关。两个物种在抗淹性上的差异似乎并非主要由茎伸长能力的不同所致，而是与生活史特征相关的淹水耐受性差异造成的。
