Competitive dynamics in two- and three-component intercrops
Competitive dynamics in two- and three-component intercrops
复制标题
DOI：
10.1111/j.1365-2664.2007.01289.x
复制
发表时间：
2007-06-01
影响因子：
5.7
通讯作者：
Jensen, Erik Steen
中科院分区：
文献类型：
--
作者：
Andersen, Mette Klindt;Hauggaard-Nielsen, Henrik;Jensen, Erik Steen
1. 间作在资源利用、减少投入和提高作物生产的可持续性方面具有潜在优势，因此受到越来越多的关注，但我们对间作物种之间相互作用的了解仍然非常有限。在大田条件下，采用替代设计种植豌豆、大麦和油菜作为单种作物和间作。我们收集了连续收获的总干物质数据，并将数据拟合到logistic增长模型中。在每次收获时，我们通过将数据拟合到简单的种间竞争模型来估计三种作物的相对竞争强度（CS）。豌豆单作在生育期中后期产生的生物量最大，但在间作中不占优势。拟合数据的逻辑增长模型强调了作物间相互作用的初始大小差异的重要性。大麦是间作的主要组成部分，很大程度上是因为它最初的大小优势。大麦对其伴生作物的竞争效应，用CS来衡量，在整个生长季节都在增加。5 .每一种作物与另一种作物一起生长时的表现与单独栽培时的表现大不相同，但添加第三种作物对单个作物的表现影响很小。合成与应用。在间作试验中纳入连续收获可以提供关于竞争等级是如何建立和随时间变化的重要信息。我们的研究结果表明，加深对物种间不对称竞争作用的理解，以及由此产生的早期发芽和幼苗出苗的优势，将对间作的设计有价值。为了设计优化的间作系统，需要更多地关注间作物种之间相互作用的控制机制。
1. Intercropping is receiving increasing attention because it offers potential advantages for resource utilization, decreased inputs and increased sustainability in crop production, but our understanding of the interactions among intercropped species is still very limited.2. We grew pea Pisum sativum, barley Hordeum vulgare and rape Brassica napus as sole crops and intercrops under field conditions using a replacement design. We collected total dry matter data from sequential harvests and fitted the data to a logistic growth model. At each harvest we estimated the relative Competitive Strength (CS) of the three crops by fitting the data to a simple interspecific competition model.3. The pea monocrop produced the largest amount of biomass from the middle to the end of the growth period, but pea was not dominant in intercrops.4. Fitting data to a logistic growth model emphasizes the importance of initial size differences for interactions among intercrops. Barley was the dominant component of the intercrops largely because of its initial size advantage. The competitive effect of barley on its companion crops, measured as CS, increased throughout most of the growing season.5. The performance of each crop species was very different when it grew with a second species rather than in monoculture, but addition of a third crop species had only minor effects on behaviour of the individual crops.6. Synthesis and applications. Including sequential harvests in experiments on intercropping can provide important information about how competitive hierarchies are established and change over time. Our results suggest that increased understanding of the role of asymmetric competition among species and the resulting advantages of early germination and seedling emergence would be valuable in designing intercrops. More focus on understanding the mechanisms that govern interactions between intercropped species is needed for designing optimized intercropping systems.