Morphological classification of traditional Philippine upland rice cultivars in upland nurseries using cluster analysis methods for recommendation, breeding and selection purposes

Using eight morphological parameters with six cluster analysis methods, a s et of 21 traditional and four improved Philippine upland rice cultivars (cv s) could be separated into five groups: (1) improved semi-dwarf plant type, (2) improved or 'moderately modified' (short) Indica plant type, (3) tradi tional tall Indica plant type, (4) traditional tall Japonica plant type and (5) traditional short Japonica plant type. The results emphasized the impo rtance of the separation into Indica and Japonica plant types, but the cult ivars could be classified more accurately using growth characteristics such as tillering ability, followed by plant height and leaf area parameters. T he clusters containing Indica cvs consistently showed a higher tiller numbe r per plant, a higher growth stage (DC classification) and narrower leaves than clusters with Japonica cvs. The parameters culm length, plant height, leaf area, leaf length and width were represented in subgroups with both lo ng and short expression of the respective characteristic. Use of the existi ng variability of morphological traits within the group of traditional upla nd rice cvs should be beneficial in recommendation, breeding, selection and development of upland rice cvs for the different rice ecosystems as well a s for the upland rice/rice blast pathosystem.