Breeding improved varieties to valorise hemp fibers for biobased materials

Hemp (Cannabis sativa L.) is a multi-purpose and low input fibre crop that fits perfectly into a sustainable and biobased society and the concept of “whole plant use”. The primary products of hemp are very strong bast fibres, which are used for building materials and textiles. In addition to the stems that provide the fibre, the hemp leaves and seeds, currently side stream, contain valuable components that can then be converted into various products for a biobased-economy. Altogether, this makes hemp a promising crop to help realize a circular and climate resilient agriculture. In order to further develop hemp into a more competitive rotation crop for such renewed agricultural systems, the currently available hemp varieties can be improved at specific points.

A known problem in hemp that needs improvement is the uneven development of plants within the crop due to the sexual dimorphism of hemp. The resulting crop heterogeneity can cause severe problems.

There are new, monoecious hemp varieties available that show a better crop homogeneity but for most varieties this trait, monoecy, is unstable and declines over generations. The reason for this is still unknown making the problem difficult to predict and control. Genetic factors, environmental factors or a combination of both may play a role. To accelerate the development of improved and stable monoecious hemp varieties, genotyping tools and a better understanding of the effect of environmental factors are indispensable.

In this project, a consortium of leading Dutch companies involved in hemp production, marketing of hemp products and sowing seed production, together with WUR Plant Breeding, will initiate research to develop key molecular tools to select and maintain improved, homogeneous and robust, monoecious hemp varieties. Whole genome sequencing will be applied to detect genome-wide genetic variation among extreme phenotypes and questions about the effect of specific genomic regions and environmental effects on monoecy and fibre quality will be answered.

The innovations and knowledge obtained in this project will facilitate the breeding of improved hemp varieties for the production of specific fibre qualities, that perform well in a changing climate. This will valorise hemp bast-fibres to keep up with the current high demand for hemp products whereas the expansion of hemp production for biobased materials will contribute to achieve the EU’s 2030 emissions targets. Upon successful implementation the project will increase the primary production of high quality hemp fibres (obtained from the stems) in The Netherlands, for use in e.g. biobased building materials while also the remaining biomass (leaves, seeds) is utilized.