Effect of crop rotation on the root system morphology and productivity of triticale (x Triticosecale Wittm)

The root and shoot characteristics of triticale grown in either a monoculture sequence of winter triticale (WT) and spring triticale or in rotation with sugar beet and faba bean (Norfolk rotation) were studied. Grain yield, root and shoot biomass as well as root morphometric parameters, were determined in a long-term field trial carried out in Poland. Spring triticale had lower root biomass and shorter root length than WT as observed at a soil depth of 5-20 cm and was related to the 0.1-0.5mm root diameter fraction. Grain yields were affected by both crop rotation (Norfolk>monoculture) and the type of triticale grown (winter>spring). Straw yield was lower for the Norfolk rotation (7.16 t/ha) than for monoculture (8.47 t/ha). Consequently, the harvest index (HI) was higher in the Norfolk rotation (0.421 v. 0.324). In conclusion, when grown in monoculture, triticale showed lower biomass production and HI compared with triticale grown in a rotation with other non-cereal crops. These differences could be caused not only by deterioration in the physical, biological and/or chemical properties of the soil resulting from the use of a monoculture rotation, but also by the beneficial effects of the organic amendments applied and the legumes grown in the Norfolk rotation.