Development of near-infrared spectroscopy calibrations to measure quality characteristics in intact Brassicaceae germplasm

Abstract

a b s t r a c tDetermining seed quality parameters is an integral part of cultivar improvement and germplasm screening. However, quality tests are often time consuming, seed destructive, and can require large seed samples. This study describes the development of near-infrared spectroscopy (NIRS) calibrations to measure moisture, oil, fatty acid profile, nitrogen, glucosinolate, and chlorophyll content in six species from the Brassicaceae family. Rapeseed and similar oilseeds are potential feedstocks for producing hydrotreated renewable jet fuel. Screening samples with NIRS would allow cultivars with desirable characteristics to be quickly identified. A total of 367 samples of six species (Brassica napus, Brassica carinata, Brassica juncea, Brassica rapa, Sinapis alba, and Camelina sativa) were scanned with NIRS. Global calibrations for all six species were developed using modified partial least squares regression with reference values obtained through wet chemistry techniques. Comparing predicted values to reference data, the coefficients of determination (r 2 ) and ratios of performance to deviation (RPD) varied, with some calibrations performing better than others. The calibration equations for seed oil content (r 2 = 0.98, RPD = 7.3) and nitrogen (r 2 = 0.98, RPD = 5.3) performed very well while the equations for seed moisture (r 2 = 0.93, RPD = 3.8) and total glucosinolate content (r 2 = 0.92, RPD = 2.3) were more qualitative. Large variation was observed for chlorophyll content (0-390 mg/kg) so two calibration equations were developed, one for the higher and one for the lower range of values. When combined, these calibrations also showed very good performance (r 2 = 0.99, RPD = 14). The performance of the calibrations for the fatty acids was more varied, with some performing very well, such as the calibration for C 18:3 (r 2 = 0.99, RPD = 9.9), and others, such as C 22:0 (r 2 = 0.69, RPD = 1.9), showing poor correlation. (E.A. Oblath), terry.isbell@ars.usda.gov (T.A. Isbell), mark.berhow@ars.usda.gov (M.A. Berhow), brett.allen@ars.usda.gov (B. Allen), david.archer@ars.usda.gov (D. Archer), jbrown@uidaho.edu (J. Brown), russ.gesch@ars.usda.gov (R.W. Gesch),

Rapid Nondestructive Analysis of Intact Canola Seeds Using a Handheld Near‐Infrared Spectrometer

“…Our results agreed with and compared favorably to previously reported results. Our SEC (1.05%) was lower than the one obtained by Oblath et al () who reported an SEC of 3.1% for oleic acid with a sample range of 7.1–65.5%. In 1994, Daun et al reported an SEP values of 4.7% and 4.8% for an oleic acid range of 55.6–65.6% for a model obtained with 13 factors (R 2 val = 0.903 and 0.909, RPD = 2.54 and 2.62).…”

“…Daun et al () used 11 and 13 factors in their models with benchtop instruments for a total glucosinolates content range of 9.7–30 μmol/g ( B. napus and B. rapa) ; their SEP and R 2 val ranged from 1.7 to 3.8 μmol/g and 0.812 to 0.899, respectively, depending on the instrument model. Oblath et al () used various Brassica species with a much larger total glucosinolates range (5.5–117.4 μmol/g); their SEC of 8.19 μmol/g was higher than the one obtained with our handheld instrument. Petisco et al () used B. napus and B. carinata to develop a global total glucosinolates model (range 15.8–97.9 μmol/g) using only seven factors.…”

“…The results compared well with previously reported results for benchtop instruments. Oblath et al () reported a SEC value of 0.59%, for a α‐linolenic acid range of 4.7–38.6%. Velasco et al () reported an SEP value of 3.44% with an α‐linolenic acid range of 1.0–69.8%, which is much larger than the range used in this study.…”

“…Daun et al () reported SEPs ranging from 0.43 to 0.55% and R 2 val ranging from 0.963 to 0.979 for canola ( Brassica napus and Brassica rapa ) seeds with oil contents ranging from 39.8 to 49.9%, whereas Petisco et al () reported an SEP of 0.54% and an R 2 val 0.98 for Brassica seeds ( B. napus and Brassica carinata ) with a higher oil content range (34.1–48.4%). Oblath et al () reported only cross‐validation results; the SEC was 0.90% and R 2 cross‐val 0.98 for the oil prediction results of a model developed using various seed samples of the Brassicacea family with an oil content range of 17.6–51.0%. The NF used in the two models also compared positively to what has been previously reported, as Daun et al () reported using 13‐NF, whereas Petisco et al () used only six NF for their model.…”

Identification of genetic variation in Brassica napus seeds for tocopherol content and composition using near‐infrared spectroscopy technique

“…Additionally, the NIRS technique has been successfully applied in Brassica species to predict seed viability (Lee et al, ; Shrestha, Deleuran, & Gislum, ), seed vigour (Kandpal, Lohumi, Kim, Kang, & Cho, ) and seed germination (Al‐Amery et al, ), as well as the seed oil content (Tkachuk, ), fibre fractions (Font et al, ; Stubbs & Kennedy, ; Wittkop, Snowdon, & Wolfgang Friedt, ), protein content (Daun, Clear, & Williams, ), and glucosinolate (Velasco & Becker, ), and chlorophyll concentrations (Oblath et al, ). The NIRS calibration for estimating the tocopherol content in sunflower seeds (Gotor, Berger, et al, ), alfalfa (González‐Martín, Hernández‐Hierro, Bustamante‐Rangel, & Barros‐Ferreiro, ) and olive oil (Cayuela & García, ) have been reported.…”