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In Central Pacific region, Mexico, are cultivated around 17,000 ha of cucurbitaceous. This crops are affected by wilt, this disease is caused by Fusarium oxysporum (F.o.) Schlechtend. Some farmers are using resistant varieties to this disease, but resistance is different to each cultivar. Soil fumigation is other way to control this pathogen. Soil solarization is a new alternative for Fusarium oxysporum control. The objective of this research was to evaluate the effect of soil solarization on Fusarium oxysporum for wilt control in muskmelon crop in Colima State. The experiment was carried out under field conditions, using Cantaloupe melon (Cucumis melo L.) Cv. Ovation, in Ixtla-huacán municipality during November-December. Clear plastic was used (thickness 110). Evaluation of solarization periods were 0, 10, 20, and 30 days. Experimental design was full random blocks, with four replications. Evaluated variables were: soil temperature at 5-,10-, and 20-cm soil depth, propagule number of Fusarium oxysporum in soil, wilt incidence and yield. For determine Fusarium oxysporum survival, a strain isolated from infected plants was used. Fungi was introduced in cloth bags, containing 10 gr of sterile sand with 10 mL of a suspension of 19,000 conidia/mL. Later were introduced four cloth bags per treatment at 5-,10-, and 20-cm soil depth. When plants were harvested, was taken the sick plants percentage. Results shown that soil solarization periods had not an effect on the propagule number at the soil depth for the solarization periods. Also soil solarization had not and effect on plant yield. Is necessary to do the same experiment during different season, as June-July or September-October, to have a higher soil temperature and humidity.

Soil solarization is used for soil born pathogens control, as a result of temperature increase in soil, around 10 °C higher than in not solarized soils. In Mexico, is mostly used to decrease cost to control of different diseases that affect to melon crop, one of them is caused by Fusarium oxysporum f. sp. melonis (L & C) Snyder & Hansen, which is characterized by wilt and yellowing in melon plants. The objective of this assay was to evaluate the effect of heat on infective capacity of F. oxysporum f. sp. melonis in melon plants and its reproduction capacity after to be under different periods of heat under laboratory conditions. Isolated was taken from melon plants from Carmelitas Ranch in the Colima Municipality. Inoculation was 1 × 10^-6 conidia concentration. Cloth bags, with 20 g of inoculated soil, were introduced at 9 cm depth in metallic pots (16 cm diameter and 18 cm depth) containing 4 kg of not inoculated soil during 24, 48, 72, 96, and 120 h, with 6 replications. After each period, 1 g was taken from the cloth bags used in heat treatments, later was diluted in 50 mL of distillated water, and petri dishes containing PDA, were inoculated with 1 mL from that dilution and inoculum viability was registered at 96 h after incubation. Parameters evaluated were: mycelium growth, propagule number, and conidia number. Results showed a positive effect to control of Fusarium oxysporum f. sp. melonis, in treatments with a higher heat period, respecting to the control. Is necessary to evaluate this technique under field conditions during summer season.