Non-destructive analysis of rapeseed quality by NIRS of small seed samples and single seeds

Abstract

Near infrared-reflectance spectroscopy (NIRS) is widely used as an efficient and nondestructive method for seed quality analysis in oilseed rape (Brassica napus L.). Normally, calibration equations are developed for seed samples sizes of 3-4 g. However, during the breeding process much less than 3 g of samples are frequently only available for analysis. The objective of the present study was to analyse whether calibration equations developed for standard sample sizes can be used to predict the oil, protein, moisture, glucosinolate and fatty acid content of sample sizes ranging from about 450 to 5 mg (single seeds). Special adapters were made for the standard ring cups to hold the smaller samples during NIRS scanning. Close Spearman rank correlations (r S = 0.82-1.00**) showed that NIRS calibration equations developed for standard small ring cups can be used to predict the oil, protein, and glucosinolate content of smaller samples of 450-100 mg seeds. For oleic, linolenic and erucic acid, close correlations were only found for adapter sizes holding 450-250 mg seeds (r S = 0.79-0.98**). Only moderate to very low correlations were found for the moisture content.The standard NIRS calibration equations could also be used to predict the oil content (R 2 = 0.79**) and the protein content (R 2 = 0.72**) of single seeds (ca. 5 mg), whereas this was not possible for the glucosinolate content (R 2 = 0.54**). Therefore, single seed NIRS calibration equations were developed for alkenyl, indole and total glucosinolate content. The coefficients of determinations in cross validation ranged from 0.83 (alkenyl) to 0.86 (indole and total glucosinolates).

Predicting rapeseed oil content with near-infrared spectroscopy

“…This variability is typically observed in Brassica napus. The accuracy of the equation in Figure 1 (SEC = 0.78 and SEP = 1.22) was similar to the one obtained by Tkachuk (1981) and Hom et al (2007). However, this accuracy was greater than the one found by Velasco et al (1999), mainly because these authors used other species from the Brassicaceae family to estimate the equation (SEC = 1.85 and SEP = 1.92).…”

New winter oilseed rape varieties – seed quality and morphological traits depending on sowing date and rate

“…Their values were used for NIRS calibrations for oil and protein contents. NIRS allows for a simultaneous analysis of seed components in intact samples such as: acid detergent fibre (ADF), neutral detergent fibre (NDF), total glucosinolate, total alkenyl glucosinolates, gluconapin, glucobrassiconapin, progoitrin, napoleiferin, glucobrassicin, 4OHIN-4-hydroksyglucobrassicin according to the methods described by Hom et al (2007), Wittkop et al (2012). Analysis of glucosinolates composition was performed using spectrometer NIRSystems 6500 in spectrum from 400 to 2500 nm and ISIscan Routine Analysis Software.…”

Genetic variation of storage compounds and seed weight in rapeseed (Brassica napus L.) germplasms

“…The quantitative and qualitative traits of seeds have been analyzed using this method in many crops of cereals and oilseeds (Charron et al 2005, Weinstock et al 2006. In rapeseed, several researchers reported that NIRS using intact-seeds is useful to estimate seed components from the viewpoint of validity of NIRS analysis on seed compositions (Font et al 2006, Sato 2008, Velasco and Becker 1998, single seed (Sato et al 1998, Velasco et al 1999, Velasco and Mollers 2002, and small seed samples (Hom et al, 2007).…”