Components of Sustainable Production Systems for Vegetables-Conserving soil Moisture

Abstract

Conservation tillage systems offer distinct advantages for crop production under erosive and droughty soil conditions. This report contains 4 years of data on the effects of in situ cereal rye and wheat mulches on yield of cabbage (Brassica oleracea L. var. capitata) grown under limited-irrigation, conservation-tillage systems. Three tillage systems were studied: conventional plow-disk (CT); strip tillage (ST) and no-tillage (NT). The summers of 1987 and 1990 were characterized by below-average total rain and periods of prolonged (45 days) of dry weather during head enlargement; cabbage yields were highest in the mulched ST and NT plots. In contrast, the 1988 and 1989 growing seasons were above average in total rain and there were no prolonged periods of dry weather. Cabbage yields were unaffected by tillage treatments in 1988, while, in 1989, yields with NT were 65% and 60% lower than with CT and ST, respectively. A combination of abundant rain, soil compaction, and delayed planting retarded plant growth in the 1989 NT plots, resulting in smaller, less-productive plants than in the tilled ST and CT plots. These data show that: 1) conservation tillage and particularly strip tillage systems are viable options for production of cabbage; and 2) rain-irrigation patterns, site selection, and planting dates are major determinants of the relative advantages of conservation tillage compared to conventional tillage systems.