Degree Type

Thesis

Date of Award

2009

Degree Name

Master of Science

Department

Agronomy

Major

Ecology and Evolutionary Biology

First Advisor

John H. Dekker

Abstract

Chenopodium album is a widespread and troublesome weed in Iowa and agricultural areas throughout the north temperate regions of the world. This study investigated the effects of various factors on the stimulation of germination of two populations of C. album seeds collected in 2007 and 2008 at a common location. These factors included light, temperature, after-ripening time, nitrate, and water level. Germination of both populations was generally stimulated by light, warm (15-25yC) and hot (25-35yC) temperatures, 0.01 M nitrate, 3 to 5 weeks of after-ripening (4yC, 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 low in cold (5-15yC) 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. The study presented herein is the foundation of this research.

Copyright Owner

Lindsey Marie Altenhofen

Language

en

Date Available

2012-04-30

File Format

application/pdf

File Size

39 pages

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