2017 Volume 61 Issue 3 Pages 107-116
Erianthus arundinaceus (Retz.) Jeswiet collected in Japan is a promising breeding material for sugarcane improvement because of its high biomass productivity and overwintering ability in temperate areas. However, its early heading behavior prevents intergeneric crossing with sugarcane under natural day length. The aim of this study is to develop a more effective delayed heading technique for the Japanese E. arundinaceus to achieve intergeneric crossings with sugarcane. Using the earliest and the latest heading accessions JW630 and JW4, respectively, as experimental materials, we evaluated the effects on their delayed heading by photoperiodic treatment (PT)—namely long-day and short-day treatments from 22 June to 23 August and from 24 August to 8 November, respectively—with different ratooning times (April, June and July). The effects on delayed heading were enhanced when PT was applied to the later-ratooning materials. The heading was delayed by –1 to 5 days in JW630 and 8 days in JW4 with the April-ratooning, and by 5 to 9 days in JW630 and 12 to 13 days in JW4 with the June-ratooning, and by 18 to 21 days in JW630 and 16 to 19 days in JW4 with the July-ratooning, respectively. As a result, headings could be delayed in JW630 and JW4 until mid- and late November, respectively, at maximum. Since pollen-germination rates in PT plots exceeded 25%, they could be used as a male parent for crossing with sugarcane. JW630 and JW4 were crossed with 40% and 80% sugarcane breeding materials, respectively, using this technology.
