Zinc in Soil and Corn Leaves in a Calcareous Rhodic Luvisol from Yucatan Mexico with Acid and Subsoiling

The productivity of corn in Yucatan Mexico is continually threatened by deficiencies of several essential microelements such as Zinc (Zn). The problem is limited to the alkalinity of the soil driving to an unavailable Zn in the soil which is not used by the plants. Another problem facing is the compaction of lower layers in the red Rhodic Luvisols that have been plowed, in an intensive use, for more than 30 years. Several studies have addressed the advantages of using acids to release zinc trapped by carbonates as well as the subsoiling to break up the underground to increase aeration and microbial activity. This work aimed to evaluate the effect of the application of sulfuric acid and sub-soiling on the Zinc contents of both soil and foliage of the CHICHEN ITZA Variety and the commercial HYBRID H-443A in a red arable Rhodic Luvisol in the state of Yucatan Mexico. Eight treatments were replicated by twice, and the results were subjected to an Analysis of Variance (ANOVA). The Determination Coefficients (r²) was calculated to evaluate the relationship between zinc in the soil and in the foliage. Zinc deficiencies were graded by comparing the results with the Critical Limits (CL) given by the literature and the Relative Sufficiency (%) was calculated. No variable showed significant statistical differences between treatments. However, Zinc, in the soil, is reduced with Sub-soiling in both cultivars. The acid, by itself, increased the availability of Zinc. The highest Zinc contents in the soil were found in CHICHEN. The HYBRID showed the lowest Zinc contents in the leaves (12.5 to 15 ppm) corresponding to 83% and 100% of Relative Sufficiency with respect to the CL. In CHICHEN the ranges of foliar Zinc were higher (14.5 to 19 ppm) with 97% and 127% of the Relative Sufficiency.