Durum wheat grain quality under organic farming conditions

Abstract. The experiment was conducted on a soil type Pellic Vertisols in the experimental field of the Institute of Field Crops – Chirpan in the period 2019 - 2022. The aim of the present study was to determine the influence of various predecessors on the grain quality of durum wheat grown under the conditions of organic farming in the region of Chirpan. Some indicators related to the quality of durum wheat grain were studied - protein content, wet gluten content, vitreousness, test weight, yellow pigments content. The influence of various predecessors on the investigated parameters related to grain quality was established. The experiment was conducted with the cultivar Progress. Averaged over the studied period under the specific agro-ecological conditions, the highest grain protein content was found for durum wheat after the predecessor peas (11.7% d.b.) and after the predecessor sunflower (11.6% d.b.), while after the predecessor cotton a lower value (11.2% d.b.) was found for this indicator. The wet gluten content after pea and sunflower predecessors (21.6% d.b.) was higher compared to the wet gluten content after cotton predecessor (19.9% d.b.). On average over the study period, the highest content of yellow pigments was found for durum wheat after predecessor cotton (19.17 Minolta b*), followed by that after sunflower (18.81 Minolta b*) and with the lowest content of yellow pigments was the variant after peas (18.54 Minolta b*).