Revista Brasileira de Engenharia Agrícola e Ambiental
versión On-line ISSN 1807-1929
MARTORANO, Lucieta G. et al. Indicators of soil water condition for soy bean under no-tillage and conventional tillage. Rev. bras. eng. agríc. ambient. [online]. 2009, vol.13, n.4, pp. 397-405. ISSN 1807-1929. http://dx.doi.org/10.1590/S1415-43662009000400005.
Soil water condition indicators were assessed in a field experiment conducted in Eldorado do Sul, Brazil. The Paleudult soil of the experimental area has been managed during eight years under no-tillage and conventional tillage. Soy bean cultivar Fepagro Rs-10 was sown on November 20, 2003, with 0.40 m of row spacing and 300,000 plants ha-1, with and without irrigation. Variables of soil, plant and atmosphere were monitored with emphasis during drought periods. Variations of the matrix water potential were monitored from 0.075 to 1.20 m of soil depth. A regular delay was observed in the soil drying process in no-tilled plots, in particular during drought periods, indicating higher water storage in no-tillage than in conventional tillage. Higher matrix water potential, lower maximum temperature and smaller thermal amplitude were observed in no-tillage, in comparison to the conventional tillage. Indirect indicators, such as plant height and leaf area index, were in accordance to the higher water storage in no-tilled plots, due to reductions of water deficit in plants. This set of indicators demonstrated the importance of evaluating crop responses in a systemic approach to soil and water management.
Palabras llave : soil water; soil tillage; water deficit; matrix water potential; soil temperature.