SUSTAINABLE SYSTEMS OF SOIL MANAGEMENT IN VEGETABLE PRODUCTION
A sequence of four lettuce and two tomato crops was grown in a field experiment on a sandy loam soil, under four soil management systems. The treatments included rotary hoeing, zero tillage, zero-tillage with an in-situ mulch crop, and a control. The in-situ mulch crop was Trifolium subterraneum, grown during the autumn and winter, into which vegetable seedlings were transplanted after senescence had occurred in the spring. The experiment was drip irrigated and carried out under optimal water and nutrient conditions. The yields of lettuce were reduced under zero-tillage without mulch, but not under the zero tillage plus in-situ mulch, which resulted in yields as high as the rotary hoed treatment. A similar trend was found for the vegetative growth of tomatoes, although fruit yields did not differ significantly between treatments because the zero tillage without mulch treatment had a greater fruit to shoot ratio. The in-situ mulch treatment effectively controlled weed growth and greatly reduced high soil temperatures. The soil surface was protected from crusting and erosion and soil organic matter was increased.
Stirzaker, R.J., Sutton, B.G. and Collis-George, N. (1989). SUSTAINABLE SYSTEMS OF SOIL MANAGEMENT IN VEGETABLE PRODUCTION. Acta Hortic. 247, 81-84