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).

The genetics of seed compounds is complex because seed quality traits might be exclusively determined by the genotype of the female parent or, depending on the genotype of the embryo, may also be affected by the genotype of the pollen parent. For many quality traits of oilseed rape (Brassica napus L.), the influence of the pollen parent is not well known. In this study, two male sterile lines (female parent) were pollinated by 10 genotypes (pollen parent) differing largely in seed quality. Field experiments were conducted at three locations in Northern Germany, with two replications in 1 yr. Pollen parents were sown in plots and 10 male sterile plants from each female parent were hand planted into the center of each plot. Seeds were harvested from pollen parents and from the interplanted female parents. Seeds were analyzed for oil, protein, and sinapic acid esters by near‐infrared reflectance spectroscopy; for glucosinolate and tocopherol content by high‐performance liquid chromatography; and for fatty acid content by gas liquid chromatography. Earlier results were confirmed in that fatty acid composition is dependent on the embryo genotype and is therefore largely influenced by the pollen parent. Significant pollen parent effects were also observed for oil content, indole glucosinolate, sinapoylglucose, total sinapic acid ester, and γ‐tocopherol contents. The F1 seed quality was positively correlated with the pollen parent seed quality. In conclusion, not only the fatty acid composition but also other seed quality traits such as oil content are influenced by the genotype of the pollen parent. This should be considered when analyzing open pollinated plants.

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