Vilson Mirdita

Determination of Mycotoxin Concentration by ELISA and Near-Infrared Spectroscopy in Fusarium-Inoculated Maize

Ear rots of maize caused by Fusarium spp. reduce grain yield and produce mycotoxins, which are harmful to humans and animals. To breed maize cultivars resistant to Fusarium spp., reliable large-scale phenotyping is essential. Our objectives were to (i) examine the precision of the ELISA method for determination of important mycotoxins, namely deoxynivalenol (DON) and fumonisins (FUM), (ii) evaluate the potential of near-infrared reflectance spectroscopy (NIRS) to estimate concentrations of DON and FUM in grain produced in inoculated maize plants, and (iii) compare the efficiency of ELISA, NIRS, and visual rating of disease severity for estimation of mycotoxin concentrations. Insignificant variation was observed between duplicate evaluations of DON and FUM by ELISA, showing the high repeatability of this method. DON and FUM determinations by ELISA were more closely correlated with mycotoxin concentrations predicted through NIRS than with visual rating of disease severity. For the prediction of DON, NIRS had very high magnitude of the coefficients of determination of calibration and cross validation (R 2 = 0.90–0.88). Thus, NIRS has a promising potential to predict DON concentration in grain samples of inoculated maize genotypes evaluated in resistance breeding programs.

A new near infrared spectroscopy sample presentation unit for measuring feeding quality of maize stover.

Maize stover is used to feed farm animals and the improvement of its quality is an important breeding goal. The main objective of our study was to evaluate a new near infrared (NIR) spectroscopy sample presentation unit for measuring feed quality of maize stover. In this context, we investigated the effect of engineering factors (use of glass interface and packing pressure) on the spectral repeatability and the effect of particle sizes (8cm, 6cm, 4cm, 0.5cm) on the calibration performance. The spectral repeatability was examined by calculating spectral variation among replicated spectral measurements collected without glass interface, with glass interface, and glass interface in combination with 3 kg and 6 kg of packing pressure. The effect of particle sizes was assessed for concentrations of nitrogen (N), neutral detergent fibre (NDF), ash and in vitro fermentability (G24), by examining calibration models. The spectral repeatability increased with the use of glass interface and packing pressure and calibration performance improved with a reduction in particle size. The study indicated that the new NIR sample presentation unit has a potential for preliminary screenings of maize genotypes for NDF and G24 in the stover of particular breeding programmes.