Characterization of soil properties in relation to maize productivity in Andosols of the western high-land of Guatemala.

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Soil properties in Andosols of the western highlands of Guatemala were investigated and evaluated in relation to maize (Zea mays L.) productivity in comparison to the standard of soil diagnosis for Andosols in Japan to provide basic information. The soil samples were collected from maize fields in 28 sites at a soil depth of 0 to 30 cm in 2008. A maize cultivation experiment was conducted with the same treatment of fertilizer application at 23 sites to discuss the influence of soil properties on maize productivity. The soils were characterized by sandy loam texture, acidic pH, low available phosphorus (P) reflecting high phosphate sorption coefficient, low exchangeable calcium (Ca) and magnesium (Mg), and high exchangeable potassium (K). Cation imbalance derived from relatively low exchangeable Mg and high exchangeable K was observed. Maize yield of the cultivation experiment ranged widely from 0.75 to 6.39 Mg ha−1. Principal component analysis summarized the soil properties into four components relating (1) organic matter and P sorption capacity, (2) soil texture, (3) exchangeable Mg and (4) P availability. Multiple regression analysis indicated that the first component generally related negatively and the third and fourth components related positively to maize yield, and these three components explained as much as 49% of the total variance of maize yield. These results suggested that soil properties greatly influenced maize productivity and low P availability due to high P sorption coefficient, and low exchangeable Mg to K ratio were the main constraints to maize cultivation in this region.