Weed seedling emergence and seed survival: separating the effects of seed position and soil modification by tillage

• Published in: Weed research Vol. 37; no. 3; pp. 147 - 155
• Main Authors: MOHLER, C. L., GALFORD, A. E.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01-06-1997; Blackwell Science; Blackwell Scientific Publications
• Subjects: Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Generalities, botany, ecology, damages, economic importance; Parasitic plants. Weeds; Phytopathology. Animal pests. Plant and forest protection; Weeds; Malvaceae; Abutilon theophrasti; Amaranthus retroflexus; Cultivated field; Seeds; Cultivated soil; Amaranthaceae; Pot experiments; Dicotyledones; Weed science; Angiospermae; Position effect; Cultural practice; Soil tillage; Weed; Property of soil; Perturbation; Plant emergence; Survival; Outdoor study; Chenopodiaceae; Chenopodium album; Plantlet; Population dynamics; Spermatophyta; Soil plant relation
• ISSN: 0043-1737; 1365-3180
• DOI: 10.1046/j.1365-3180.1997.d01-21.x

Summary
Tillage causes both vertical redistribution of weed seeds and changes in soil physical properties. These two factors are rarely distinguished in studies of the impact of tillage on seedling emergence or seed survival. In this study, seeds of Chenopodium album L., Amaranthus retroflexus L., and Abutilon theophrasti Medik, were planted at particular depths in pots of undisturbed or stirred soil to separate these effects. Emergence and survival data were analysed by non‐linear regression to determine the nature of significant differences between treatments. Emergence increased with slight burial and then decreased exponentially at greater depths. Average emergence over all depths was generally greater in tilled sou than in unfilled soil, particularly for C. album and A. retroflexus. Seed survival approached a maximum with increasing depth. Average survival of seeds that did not produce emerged seedlings was greater in tilled soil than in untilled soil for C. album and A. retroflexus. Thus, tillage affects emergence and seed survival of weeds through changes in soil conditions independently of effects resulting from redistribution of seeds in the soil profile.