The effect of epiphytic algae on the growth and production of Potamogeton perfoliatus L. in two light conditions
The effect of epiphytic algae on the growth and production of Potamogeton perfoliatus L. in two light conditions
复制标题
DOI：
10.1016/j.envexpbot.2004.02.001
复制
发表时间：
2004-12-01
影响因子：
5.7
通讯作者：
Fujino, T
中科院分区：
文献类型：
--
作者：
Asaeda, T;Sultana, M;Fujino, T
附生藻对淡水沉水大型植物生长和生产影响的直接证据很少。为了获得关于这一现象的更可靠、定量的数据，在控制条件下，用沉水大型植物perfoliatus进行了84天的实验室实验。试验采用2 × 2因子设计，包括两种附生条件（有附生藻类和没有附生藻类）和两种光照条件（高光照和低光照）。通过测定植株在第14、28、42、70和84天的生物量、叶片叶绿素a浓度和净光合作用来研究植株的生长和生产情况。同时测定了附生藻类叶绿素a浓度。分别于第14、30、70和84天测定植株的形态参数。在高光照条件下和低光照条件下，附生藻叶绿素a浓度在试验期间均显著升高。受附生藻负荷和弱光条件的影响，植物的总芽长、新招芽数和叶表面积的扩张或收缩都发生了显著的形态变化。强光条件下的生物量（地上和地下）和净光合速率均高于弱光条件，但叶绿素a浓度始终高于强光条件。两种光照条件下，无附生藻类植物的叶绿素a浓度、地上生物量积累和净光合作用均显著高于有附生藻类植物。在两种光照条件下，有附生藻的植株死叶干物质均大于无附生藻的植株。因此，附生藻类和弱光现象都会降低生长和产量。一般来说，植物倾向于通过改变其生理和形态来优化弱光产生的阴影，但在本实验中，当附生藻类产生的阴影发生在叶表面时，植物无法做出同样的反应。(C) 2004 Elsevier B.V.版权所有
Direct evidence of epiphytic algal effects on the growth and production of freshwater submerged macrophytes is scarce. To obtain more reliable, quantitative data about this phenomenon, a laboratory experiment was carried out over 84 days in controlled conditions with the submerged macrophyte, Potamogeton perfoliatus. It was based on a 2 x 2 factorial design with two epiphytic conditions (with epiphytic algae and without) and two light conditions (high and low). Growth and production was investigated by measuring biomass, chlorophyll a concentration of leaves and net photosynthesis of the plants on Days 14, 28, 42, 70 and 84. The chlorophyll a concentration of epiphytic algae was also measured on these days. Morphological parameters of the plants were measured on Days 14, 30, 70 and 84. The chlorophyll a concentration of epiphytic algae increased significantly over the experimental period in both HLE (high light with epiphytic algae) and LLE (low light with epiphytic algae) treatments. Plants showed significant morphological changes in total shoot length, number of newly recruited shoots and expansion or contraction of the leaf surface area due to the epiphytic algal load and low light condition. The biomass (both above and below ground) and net photosynthesis rate was higher in high light than in the low light condition, but the chlorophyll a concentration was always higher in the low light condition than in the high light condition. In the plants without epiphytic algae, the chlorophyll a concentration, above ground biomass accumulation and net photosynthesis was significantly higher than in plants with epiphytic algae in both light conditions. The dead leaf dry matter was greater in the plants with epiphytic algae than in those without epiphytic algae in both light conditions. Therefore, epiphytic algae and low light phenomena both reduce growth and production. In general, plants tend to optimize low light-created shade by changing their physiology and morphology, but they could not respond to the same when epiphytic algae-created shade occurred on the leaf surface in the present experiment. (C) 2004 Elsevier B.V. All rights reserved.