| Popis: |
A process-oriented model is presented for the description of root growth in dicotyledonous seedlings with taproots. The model is being developed to describe the relationships between root growth and colonization of the root by various microorganisms and infection by soilborne pathogens. The model is based on processes depicting the initiation and development of root segments. A root segment is defined as that portion of a root between successive branches or from the most terminal branch to the root tip. Each segment is identified by its root order, according to the morphometric root analysis system, and root type. Three root types are recognized: taproot, primary and secondary lateral roots, and basal roots. The model begins with planting, proceeds through seed germination and taproot formation, primary and secondary lateral branching, and basal root initiation and branching. The time delays between successive stages are major determinants of the dynamics of the model. The model is adaptable to fibrous root systems and monocotyledonous seedlings. |
