Thermal, physical and morphological properties of durum wheat

Abstract

The aim of this study was to evaluate selected physical, morphological and thermal properties of durum wheat grain. Additionally, the parameters of control grain (grown without fertilizers or a growth retardant) were compared with the grain from treatments with different combinations of nitrogen fertilizer and growth retardant. The grain of durum wheat grown without nitrogen fertilizer or growth retardant was characterized by the lowest values of thousand-kernel weight (47.24 g for the sample collected in 2015 and 45.70 g for the sample collected in 2016), bulk density (814 kg m−3—2015 and 745 kg m−3—2016), length (7.62 mm—2015 and 7.54 mm—2016), width (3.35 mm—2015 and 3.32 mm—2016) and shape factors (specific perimeter of object boundary, Danielsson coefficient). The highest values of thousand-kernel weight, bulk density and width of durum wheat grain harvested in both years of the study were determined in the samples collected in the treatment with a total nitrogen rate of 80 kg ha−1 without the growth retardant. In the samples collected in 2015, the above combination produced grain with the greatest length, the highest specific perimeter of object boundary and the highest Danielsson coefficient. In 2016, these parameters were highest in grain from the treatment where a total nitrogen rate of 80 kg ha−1 was combined with a growth retardant. Different combinations of nitrogen fertilization and the growth retardant did not affect the true density or the thermal properties of wheat grain. Statistically significant differences between the experimental groups were not observed.