Lindsey M. Altenhofen, Jack Dekker
Applied Ecology and Environmental Sciences. 2013, 1(6), 133-142DOI:
Abstract: Chenopodium album is a common, widespread and troublesome weed in agricultural areas throughout the north temperate regions of the world. A primary reason for this flexible adaptation relies on the complex regulation of seed germination and recruitment. The control of seed germination bythe interaction of light, temperature, after-ripening time, nitrate, and water level was investigated in a factorial experiment under controlled environmental conditions. Stimulation of germination was evaluated in two populations of C. albumseeds collected in 2007 and 2008 at a common Iowa, USA location.Germination of both populations was generally stimulated by light, warm (15-25°C) and hot (25-35°C) temperatures, 0.01 M nitrate, 3 to 5 weeks of after-ripening (4°C, dark, moist), and with the 2008 population, 1.0 and 1.25 ml of water. The interaction of these factors, particularly light, warm temperatures and nitrate, stimulated higher germination than when applied individually. Germination was very lowin cold (5-15°C) temperatures or darkness, regardless of other treatments applied. The goal of this experiment was to lay a foundation with two local Iowa populations to guide further studies developing a seed germination assay to determine variability of dormancy among individual seeds of and between populations. Insights about dormancy variability in C. album gained from the current research included positive responses by both populations to light, warm and hot temperatures, nitrate, and intermediate after-ripening times. However, the populations differed in their response to water quantity and, for most conditions, the 2008 population achieved greater overall germination. The overarching goal of this project is to build a condensed C. album seed germination assay to characterize individual populations to predict seedling emergence patterns in agricultural soils in an effort to decrease interference with crop productivity.