D'Hertefeldt Tina, Falkengren-Grerup Ursula
Plant Ecology, Ecology Building, Lund University, SE-223 62 Lund, Sweden.
Environmental management and Biotechnology, Scottish Crop Research Institute, Invergowrie, Dundee DD2 5DA, Scotland, UK.
New Phytol. 2002 Dec;156(3):469-477. doi: 10.1046/j.1469-8137.2002.00529.x.
• Physiological integration between ramets is beneficial when acquiring heterogeneously distributed resources, and is hypothesized to occur when the benefits of resource sharing outweigh the costs. Our aim was to investigate if resource availability affected physiological integration in Carex arenaria and Carex disticha. • Ramet systems were grown in high potassium and high water (K+ W+), high K and low water (K+ W-), or low K and high water (K- W+) for 1 month. Thereafter, water and K transport were traced with erythrosin and rubidium, respectively. • Carex arenaria and C. disticha transported erythrosin over seven ramet generations and rubidium throughout the whole ramet system, but C. arenaria exported 20% more rubidium from the labelled shoot than C. disticha. A detailed analysis of a subset of plants suggested that C. disticha in low K abundance shared more rubidium than in high K abundance, and that C. arenaria ramets in both K+ W- and K-W+ shared more resources than K+ W+ ramets. • We demonstrated long-distance resource transport for K and water in C. arenaria and C. disticha. The distance of integration was not affected by resource availability in C. arenaria or C. disticha, but local concentrations of K showed marked and contrasting responses to nutrient and water treatment in both species.
• 分株之间的生理整合在获取异质分布资源时是有益的，并且据推测，当资源共享的益处超过成本时就会发生。我们的目的是研究资源可用性是否会影响砂苔草和异穗苔草的生理整合。
• 分株系统在高钾高水（K+W+）、高钾低水（K+W-）或低钾高水（K-W+）条件下培养1个月。此后，分别用赤藓红和铷追踪水分和钾的运输。
• 砂苔草和异穗苔草在七个分株世代中运输赤藓红，在整个分株系统中运输铷，但砂苔草从标记茎中输出的铷比异穗苔草多20%。对一部分植物的详细分析表明，低钾条件下的异穗苔草比高钾条件下的异穗苔草共享更多的铷，并且在K+W-和K-W+条件下的砂苔草分株比K+W+条件下的分株共享更多的资源。
• 我们证明了砂苔草和异穗苔草中钾和水分的长距离资源运输。整合距离不受砂苔草或异穗苔草资源可用性的影响，但两种植物中钾的局部浓度对养分和水分处理表现出明显且相反的反应。
