Influence of edaphoclimatic conditions on stem production and stem morphological characteristics of 10 European hemp (Cannabis sativa L.) varieties

Abstract

Six dioecious (Antal, KC Dóra, Kompolti hibrid TC, Monoica, Tiborszallasi and Tisza) and four monoecious (Fedora 17, Futura 75, Santhica 27 and USO 31) European hemp varieties were sown at a density of 300 viable seeds per m2 and a row spacing of 12.5 cm in a three-year field trial (2017-2019) to evaluate the yield of the stems (fresh and dry) and some other biometric characteristics of the stems. No pesticides were used during plant growth to suppress weeds, diseases and pests. The highest yield of fresh and dry stems was achieved by the variety Antal with 12.3 t ha-1and 5.3 t ha-1, respectively, followed by the varieties Futura 75 and Tiborszallasi. The lowest yields of fresh and dry stems were recorded for the monecious variety USO 31 (6.0 and 2.6 t ha-1). In general, dioecious varieties had higher and thicker stems than monoecious varieties. The year of production had a highly significant impact on all variables, in particular on the proportion of weed biomass, which was the highest in 2019 (77.2 %), when weather conditions were most unfavourable for hemp cultivation. The correlation analysis between fresh/dry stem yields and weed biomass was highly negative (-0.85 and -0.83) and strongly statistically significant (p < 0.001), indicating the issue related to weed management.