Impact of Iodine Biofortification on Greenhouse Melon (Cucumis melo L.) Growth and Production

Aims: Evaluate the impact and biofortification of iodide (I-) and iodate (IO3-), on melon morphology and physiology under greenhouse conditions. 
Study Design: Experimental design was completely randomized with a 2x2x3 factorial arrangement, for a total of 12 treatments and 4 repetitions, giving a total of 48 experimental units. Means were compared using LSD test at 0.05. 
Place and Duration of Study: Experiment was established in greenhouses of Universidad Autónoma Agraria Antonio Narro, Saltillo. Coahuila. Mexico, between April and July 2020. 
Methodology: Iodine applications were made 15 days after transplant, with a total of 10 applications to substrate and 5 foliar applications during experiment. Treatments consisted of potassium iodide (KI) applications directly to the substrate and foliar at 0.0, 0.5 and 1 mM of iodide (I-), every week to the substrate and every 15 days in a foliar way. In same way, with potassium iodate (KIO3) treatments, applying 0, 0.5 and 1 mM of iodate (IO3-). 
Results: Applications of 1 mM iodate to the substrate increased the number of leaves and leaf area. Yields decreased where iodine was applied. Nitrogen uptake improved in almost all applications of iodide and iodate. Potassium decreased with iodide and iodate applications. The concentration of iodine in the stage of flowering and maturity with applications of iodide to the substrate 1 mM. Iodine concentrations in melon fruit were better at low concentrations of foliar applied iodide and 0.5 mM substrate. 
Conclusion: Applications of iodide and iodate have a positive effect to melon fruits, without presenting phytotoxic effects.