The microstructure observation of seed surface structure is needed for protocols of breaking dormancy of seeds with physical dormancy. The seeds of Rubus species are surrounded by a thick, hard endocarp; together, the seed and endocarp make up the stone. We evaluate stone characteristics of 18 species of Rubus through optical microscopic observation, and correlate different stone characteristics with endocarp thickness. As a result of stone size comparison, Rubus species were classified as big stones group including R. parvifolius and R. idaeus, small stones group including R. longisepalus var. longisepalus, R. corchorifolius and R. hirsutus, and middle stones group including rest of the species. The result of this study revealed that stone size and the endocarp thickness in Rubus species was various characteristics in each species. Furthermore stone size and stone weight were also well correlated endocarp thickness and result indicated that heavy stones had harder endocarp than lighter one. Thus from the result of this study it can be presumed that only one stone characteristic approach may be sufficient to estimate other characteristics in Rubus.

One objective of soybean breeders is to develop cultivars with elevated oleic acid content. Testing soybean seeds for oleic acid content is possible using gas chromatography (GC), however it is time-consuming and requires destructing the seeds. Using single seeds, we developed a near-infrared reflectance spectroscopy (NIR) calibration equation relating oleic acid measured with GC to oleic acid predicted by NIR. The slope of the regression line of oleic acid measured with GC on oleic acid predicted by NIR and the intercept was not different from zero. A set of 300 soybean seeds was used to calculate the NIR equation and an independent set of 100 soybean seeds was used for validation. This NIRS equation showed significant correlation between reference values and NIRS estimated values based on the SEP, r2, and the RSP of reference data to SEP. This research shows that NIR prediction of oleic acid using intact soybean seeds is accurate and rapid and should be especially useful for early generation screening.