Effect of gypsum, deep ripping, and irrigation on determinate tomatoes

Abstract

Treatments of gypsum, deep ripping, and level of irrigation were applied to alluvial soils at Carnarvon, Western Australia, to assess the effect on yield of determinate tomatoes. Yield was increased (P<0.05) from 3 1.9 to 41.5 t/ha when gypsum (5 t/ha) was applied and increased (P<0.05) with level of irrigation (65.6 t/ha at 699 mm v. 14.9 t/ha at 270 mm). Blossom end rot and total soluble solids in fruit were significantly (P<0.05) higher at low and medium irrigation (355 mm) levels than at the high level. Total soluble solids increased significantly (P<0.05) when gypsum was applied to deep-ripped treatments. Dispersion of soil colloids was significantly (P<0.05) reduced by gypsum. Deep ripping to 0.6 m removed the soil hardpan but had no effect on tomato yield or dispersion.