Does Surface or Subsurface Tillage Influence Burley Tobacco Yield, Leaf Temperature, or Alkaloid Content?

摘要

Transplanted crop growth can be adversely affected by soil compaction. Subsoil tillage is commonly used when compaction is suspected. No-tillage (NT) fields are often thought to be compacted although seldom confirmed by soil bulk density (BD) prior tosubsoiling. The objectives of this study were to investigate the effects of surface and subsurface tillage on tobacco (Nicotiana tabacum L.) yield, soil BD, leaf temperature, and leaf alkaloids and to correlate tobacco leaf temperature, leaf alkaloid levels, and soil BD with root-caused yield limitations. In five trials, surface tillage main plots consisted of no-tillage (NT) and conventional moldboard tillage (CT), with the absence/presence of subsoiling as subplots. Soil BD values were influenced bytillage and varied with site-year and sampling depth. They were also influenced by sampling location and the surface traffic pattern, but were not yield limiting. The CT system favored yield in three of five site-years by 6 to 38%, but