Soil moisture tension and nitrogen fertilization on cantaloupe melon: Part II [Tensión de humedad del suelo y fertilización nitrogenada en melón cantaloupe: Segunda parte]

In 2002, a field experiment was carried out to increase yield and quality of export marketable Cantaloupe melon fruit (Cucumis melo L.) in a Typical Argisustoll soil of Colima, México. Four N doses were applied to the soil (0, 80, 120 and 160 kg ha -1) and three target soil moisture tensions (10, 25, and 45 kPa) were used. During crop development, fertilization of 90 kg N ha -1 was applied with irrigation to all the treatments from blossoming to first harvest. Application to the soil of 80 kg plus 90 kg N ha -1 in the irrigation water had a positive effect on total fruit yield of categories 6 and 9. Fruit yield response to soil moisture tension was linear; the highest yield was reached with 10 kPa of soil moisture tension. The soil water tension calculated for zero yield condition was 191 kPa. It was calculated that yield decreased at a rate of 0.406 Mg ha -1 for each kPa of diminished soil moisture. The interaction Nxsoil moisture tension was significant (p?0.05) and affected fruit yield, as well as the number of aborted and matured fruits; however, when N was lacking, soil moisture did not affect yield. The application of 80 kg N ha -1 (170 g total N) and 10 kPa moisture tension yielded 15 and 27% more fruit than the same N doses applied at 25 and 45 kPa of soil moisture tension. The application to the soil of 120 kg N ha -1 (210 kg total N) at a tension of 10 kPa increased yield 13.5% and 24.6% more than at 25 and 45 kPa. Calculated yield with a multiple regression equation (R 2=0.96) was 81.1 Mg ha -1 with N=142 kg ha -1, and 10 kPa of soil moisture, which maximized 0Brix content (10.0) and yield. Fusarium was identified as the causal agent of plant wilt for melon