Influence of soil moisture content on soil solarization efficiency

Soil temperature under plastic cover is a function of incoming radiation and thermal characteristics of the mulching material and the soil. A field experiment was conducted at Fudhiliyah Agrometeorological research station to investigate how soil temperature is influenced by different soil moisture content regimes during soil solarization. Two soils, sandy loam and silty clay loam, were brought to five volumetric moisture regimes (M1–M5). The moistened soils were mulched with 180-μm-thick transparent polyethylene. Measurements of hourly soil temperatures for depths of 0.00, 0.05, 0.10 and 0.30 m were recorded from 1 June to 30 September. The results showed that the maximum soil temperatures decreased with increasing soil moisture content. The relationship between the hourly rise in soil temperature and heat flux were significantly affected by soil moisture content. Moreover, soil solarization efficiency decreased with increasing moisture content. The higher temperatures in both soils under the M4 irrigation regime resulted in faster eradication of the pathogenic fungus, Fusarium oxysporum (sp. lycopersici).