摘要

Fast kernel drydown is an important trait that corn (maize) (Zea mays L.) breeders need to select for in short-season growing regions. Hybrids with faster drydown rates will decrease costs associated with forced air kernel drying after harvest. The goal of our research was to develop a tool that could be used to non-destructively measure kernel moisture in the field, thereby allowing the selection of genotypes with faster kernel drydown rates. An Electrophysics moisture meter model MT808 was modified with two steel pins which penetrated the husk and kernels to measure kernel moisture content. Analysis of the influence of husk and cob (rachis) on meter readings and moisture measurements was also conducted. The results indicated that the modified MT808 can be used for measuring corn ear and kernel moisture. Meter readings and kernel moisture, measured after destructive sampling and oven drying, were highly correlated. Total ear moisture readings (readings taken by inserting the pins thru the husk and into the kernels) could be used to predict oven dried kernel moisture, using the calibration curve y = 1.11x (r(2) = 0.79). Genotypic differences in kernel moisture were measurable using this meter. Husks influenced moisture measurements more in the early stages of ear development; while cobs influenced moisture measurements when kernel moisture was between 20-60%. The use of this modified hand-held moisture meter can be used to improve the selection for kernel drydown in short-season corn as this meter records data faster and is lighter weight and easier to use in the field than previously used meters.