Influence of agronomic factors on yield and quality of hemp (Cannabis sativa L.) fibre and implication for an innovative production system

Research and development of an innovative production system for hemp (Cannabis sativa L.) fibre for textile use requires the integration of multidisciplinary knowledge from cultivation technique to realization of end products. Research was carried out to study the effect of the agronomic factors cultivation year (2003-2004), genotype (Futura 75 and Tiborszallasi), plant population (720, 240 and 360 plants m(-2)) and harvesting time (beginning and full flowering) on fibre yield and quality in the whole hemp stem, and in the basal and apical stem portions separately. The study of separate stem portions was done to determine the effect on fibre quality of an innovative harvesting and processing system in which hemp stems are cut in two portions of approximately 1 m at harvest to enable processing on modern flax scutching lines. Stem and fibre yield were affected by most of the agronomic factors. The extreme drought experienced in the first year reduced stem and fibre yield, but stems had higher percentage of fibre (16.5%), that were finer (22.9 mu m) and with a higher degree of maturity (73.6%) in 2003 than in 2004 (respectively 16.0%; 24.5 mu m; 55.8%). Between the two genotypes under trial the monoecious Futura 75 largely out yielded the dioecious Tiborszallasi in both years. The latter however had finer primary fibres and less secondary ones. In both genotypes primary fibres maturity and quantity of secondary fibres increased at later harvest. Plant population affected stem biometrics and fibre characteristics, with finer fibres and less secondary growth at higher stands. It can be concluded that cultivation technique can be exploited in order to maximize the quality and yield of stems destined for the innovative harvesting and processing system herein described. (C) 2008 Elsevier B.V. All rights reserved.