This work, carried out at Research Centre for Industrial Crops of CREA in Rovigo, aimed at assessing the performance of a modified combine header and seed losses during late harvest of 5 hemp varieties. The renewed interest in Italy for hemp cultivation is aimed at seed production unlike the traditional cultivation aimed at fibre. However, it must face the lack of monoecious varieties suitable for Italian environment. In the case of dioecious varieties, traditionally cultivated in Italy for fibre production, the high crop height makes it difficult the mechanical harvesting with conventional combines. Similarly, the uneven height recorded in the case of imported varieties for seed production, requires adjusting continuously the height of the combine header. So, modified combine headers capable of be moved upwards and downwards by a lift have been developed. The aim is to avoid the risk of possible clogging of threshing apparatus introducing big pieces of stalks. Moreover, in this way, the stalks can be harvested separately in order to increase the income for farmers. In view of valorise the whole plant, as multipurpose crop, the right harvest time should be a trade-off between seed yield and fibre quality. Early harvesting guaranties a good fibre quality but causes also the harvest of seed not completely ripened. On the contrary delaying the harvest reduces the seed yield due to seed loss for dehiscence. In addition to losses for dehiscence prior to harvest, the trials aimed at distinguishing the loss incurred during harvest attributable both to crop disturbance by combine header and to the setting of the combine’s threshing and separation elements.

Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 197-200