2018 Volume 87 Issue 2 Pages 165-175
Improvement of cane yield is essential to enhance sugar productivity in the South-western islands of Japan. In the present study, to identify certain traits related to high yield in the South-western islands, we investigated the growth and dry matter production of three high yielding backcrossed first generation (BC1) clones developed by back-crossing an interspecific hybrid derived from Saccharum spontaneum with commercial cultivars. Shoot and root dry weights, and other related traits including leaf area index and specific leaf area of the BC1 clones were measured at different growth stages, and were compared with those of commercial cultivar. The BC1 clones showed 30–58% higher yield, higher specific leaf area at the initial growth stage, higher leaf area index and leaf dry weight throughout the growth period, and vigorous root development at the initial growth stage. Although the photosynthetic rate was also measured during the growth period, there was no significant difference between the commercial cultivar and the BC1 clones. In conclusion, higher yield of the BC1 clones was suggested to be achieved by higher partitioning of assimilates to the leaf at the initial growth stage followed by rapid increase in leaf area index. Better root system development especially at the initial growth stage could contribute to supply enough water and nutrients to the shoot.
