Characteristics of dry matter production and partitioning in edible yam (Dioscorea spp.) cultivars

Seven yam (Dioscorea spp.) cultivars belonging to three different species, D. rotundata, D. alata, and D. esculenta were grown in the field. The yield was found to be highest in D. rotundata followed by D. alata and D. escule nta. The rate of dry matter (DM) production (mean crop growth rate) did not show significant association with tuber yield. But partitioning of DM (har vest index) showed significant positive association in D. rotundata (r = 0. 9543*), D. alata (r = 0.9376*), and D. esculenta (r = 0.9614*). The regress ion analysis of partitioning of DM to different plant parts showed signific ant DM accumulation in vines. The highest partitioning coefficient for tube r growth in D. rotundata (b = 0.6994) cv. Sree Priya suggested better utili zation of DM and showed highest tuber yield.