Soil application of dazomet combined with 1,3-dichloropropene against soilborne pests for tomato production.

There is a growing problem in China, whereby tomato replant disease is being affected by Fusarium spp., Meloidogyne spp., and Phytophthora spp. To address these pests that live in the soil, we evaluated how well applying a dazomet (DZ) and 1,3-dichloropropene (1,3-D) combination directly to the soil works in three different tomato trials. The combined treatment of DZ + 1,3-D (25 + 10 g a.i. m⁻²), applied at a 50% reduction rate, effectively decreased Meloidogyne spp. populations in the soil by more than 94%. This resulted in low root galling indices of 2.67%, 4.17%, and 10.83% in the different trials. In addition, it significantly decreased the number of Fusarium spp. and Phytophthora spp. colonies by more than 82%, resulting in low root disease indices of 3.33%, 10.00%, and 10.42%, respectively. This also greatly increased tomato yield and profit for growers. The results obtained with DZ alone and methyl bromide (MB) at 50 g a.i. m⁻² were similar. However, these results were better than those obtained with 1,3-D at 20 g a.i. m⁻² alone in controlling soilborne fungi in trials I and III. Compared to the untreated controls and the soil solarization disinfestation treatments, all the chemical treatments performed significantly better. Due to its effectiveness in controlling pests and its economic advantages, soil fumigation with DZ + 1,3-D (25 + 10 g a.i. m⁻²) is recommended in pest management programs for tomato cultivation in China. This treatment is highly effective in managing pests that reside in the soil.