Determination of chemical composition and nutritional attributes of silage corn hybrids by near-infrared spectroscopy on chopper: evaluation of traits, sample presentation systems and calibration transferability

Determination of dry matter and feeding value of silage corn (Zea mays L.) limits the number of genotypes that can be evaluated in breeding programmes. Measuring plot material by near-infrared spectroscopy on chopper (NOC) allows to increase the number of genotypes to evaluate, and improves dramatically the efficiency of the data collection processes. The objectives of our study were to (i) compare the performance of two NOC sample presentation systems (conveyor belt vs. spout) for determination of dry matter and feeding value of silage corn hybrids (ii) identify limiting parameters in the performance of alternative NOC sample presentation designs and (iii) evaluate the calibration transferability between NOC systems equipped with different sample presentation designs. Two chopper machines were equipped with near-infrared diode array spectrometers. Sample presentation designs comprised the conveyor belt and spout systems. Drying-oven and laboratory near-infrared spectroscopy were used as reference methods to develop NOC calibrations. In association with its higher dynamic signal range the conveyor belt system yielded lower standard errors of prediction than the spout system for most traits. Calibration transferability between NOC systems with different sample presentation designs was feasible.