Soybean row spacing and weed emergence time influence weed competitiveness and competitive indices
| Autor: | Stevan Z. Knezevic, John L. Lindquist, Alex Martin, Shawn M. Hock |
|---|---|
| Rok vydání: | 2006 |
| Předmět: |
0106 biological sciences
Relative scale fungi food and beverages Sowing 04 agricultural and veterinary sciences Plant Science respiratory system Biology 01 natural sciences 010602 entomology Agronomy Yield (wine) Competitive index parasitic diseases 040103 agronomy & agriculture 0401 agriculture forestry and fisheries Dry matter Weed Agronomy and Crop Science |
| Zdroj: | Weed Science. 54:38-46 |
| ISSN: | 1550-2759 0043-1745 |
| DOI: | 10.1614/ws-05-011r.1 |
| Popis: | Weed competitiveness can be quantified with the concept of competitive index (CI), a relative scale of weed competitiveness. Field studies were conducted in 2002 and 2003 in northeastern and southeastern Nebraska to evaluate the influence of soybean row spacing and relative weed emergence time on the competitiveness of major weed species in soybean. Ten weed species were seeded in soybean spaced 19 and 76 cm apart at the planting, emergence, and first trifoliate leaf stages of soybean. Total weed dry matter (TDM), weed plant volume, and percent soybean yield loss were arbitrarily selected as a base for determining the CI for each weed species. Soybean yield loss was the least variable parameter used to quantify weed competitiveness and rank their CIs. In general, weeds grown with soybean planted in 19-cm rows produced less TDM, plant volume, and reduced soybean yield less than weed species grown in 76-cm rows. Later-emerging weeds produced less TDM, plant volume, and reduced soybean yield less than the early-emerging ones. In general, broadleaf species were more competitive than grass weed species. Common sunflower was the most competitive weed species in this study. |
| Databáze: | OpenAIRE |
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