IMPROVING FLOWERING OF SUGARCANE FOR BREEDING: PROGRESS AND PROSPECTS

摘要

Flowering of parental germplasm at BSES Meringa is variable and moderate. Consequently, genetic improvement of the Australian sugar industry cannot be fully-effective. This paper summarizes field and photoperiod facility (PF) research conducted to resolve this problem. Regulated field irrigation improved flowering, but under high temperature conditions adequate soil moisture was not a sufficient condition for flowering. Research failed to explain two aberrant flowering effects. Initial PF research produced variable results suggesting uncontrolled variables in photope-riodic regimes and/or plant management. A far-red canopy treatment at the beginning of the dark period, or imposition of a dark break during the day, failed to increase flowering. Recent PF research yielded excellent induction levels, particularly during cooler periods. Misting to maintain canopy temperature <30℃ produced poor and variable induction. Staged exposure of plants to temperatures >35℃ during induction suggested photoinduction sensitivity. Duplication of PF facilities to produce a majority of required panicles is dependent upon verification of research results. Operating PFs twice yearly will reduce output costs, but a timing offset from natural induction may be necessary until high-temperature inhibition of photo-induction is fully understood and management strategies developed.