Fig. 2. Biplot of the first two ordination scores for standardized number of spikelets per panicle (SPP) for diverse rice cultivars in six managed environments. The environment vectors are labeled as in Table 1. The codes for cultivars are from Table 2. PCA = principal component axis. Group S1, comprising Cultivars 7, 17, 25, 36, 44, and 48, clusters at the origin and has been omitted.