Wild Hemp Cannabis ruderalis Janisch and Sugar Beet

Abstract

This paper describes the biological properties of wild hemp Cannabis ruderalis Janisch, an original weed species under Central-European climatic conditions of South and East Slovakia, with the potential of high economic importance especially concerning some localities of the country where sugar beet is grown. It also outlines the specifics for agronomical and herbicidal management of sugar beet stands against the weed, these procedures improve the herbicides efficiency based on 2-3 times repeated or divided application of mixed herbicides based on phenmedipham, desmedipham, ethofumesate and chloridazon until the hemp plants have 2-4 leaves, respectively their efficiency can be improved by further mixtures with triflusulfuron-methyl or metamitron, which is effective also when used on its own preemergently or postemergently. The paper also describes the sensitivity of wild hemp to many other herbicides commonly used in the protection of field crops stands cultivated in Slovakia as fore crop or after crop of sugar beet.