Prediction of Sprouting Capacity Using Near-infrared Spectroscopy in Potato Tubers

Abstract

The potential of near infra-red spectroscopy (NIRS) for predicting the sprouting capacity of potato (Solanum tuberosum L.) tubers was investigated. The experiment was conducted for 2 years using ‘Superior’ and ‘Atlantic’ potatoes. A total of 380 potato tubers (200, Superior; 180, Atlantic) weighing 100–200 g were scanned by NIRS, and the sample sets were divided into four groups; three groups were classified based on the cultivars or years as follows: ‘Superior’, 2004; ‘Superior’, 2005; ‘Atlantic’, 2005; the fourth group contained the total number of samples. The reference value for the sprouting capacities was measured by determining the sprout weight after 30 days of incubation at 20°C. The first derivative transformation equation for raw optical data was standardized by applying standard normal variate (SNV) and detrending (DT) algorithms, and calibration equations between them were developed by modified partial least square (MPLS) regression. The coefficient of determination (r2) ranged from 0.868 to 0.965 with a standard error of calibration (SEC) from 0.31 to 0.40 for the calibration sets; r2 ranged from 0.724 to 0.904 with a standard error of prediction (SEP) from 0.532 to 0.602 for the four validation sets. These results indicate that the calibration model obtained from this experiment is applicable to all the different cultivars for different years, and the NIRS method is a powerful tool for the predictive assessment of the sprouting capacity of potato tubers.