Reduction in Intergeneration Time Interval in Selection of Sugarcane Varieties through Population Testing

Abstract

Traditionally, the variety testing scheme spans over a period of 13 to 15 years. In most countries all releases are based on small plot (i.e. seven stage) trials and small mill analysis. Rarely field planting and large mill tests are carried out with a crush of an hour which is the minimum time required. The current selection programme suffers from old concepts with sample testing and extrapolation of the data, which does not withstand the rigours of field conditions. The gap between the trial plots and field is large on both counts namely Pol% cane and yield. This paper discusses the population-testing concept to facilitate large mill testing and cutting down intergeneration time interval for releasing varieties. In the current scheme, the intergeneration time interval for releasing varieties is reduced from 13 years to 6 to 8 years. This was possible with a change in the variety testing concept. It was a population testing concept which includes early selection based on heritable characters like brix, fibre, pest and disease resistance and later 2.0 ha and more under field conditions. The best clones are taken for multiplication at three locations using single eye buds. The principle is that instead of using small plots, larger populations at three locations are used. The three varieties viz., PI 96-0151, PI 97-0843 and PI 97-1946 were multiplied along with Co 86-032. These varieties were tested in the large mill for their performance and behaviour under field conditions and compared with the standard variety Co 86-032. All the three varieties recorded higher yield and POCS% when compared with Co 86-032. The early and advance yield trial results are discussed and confirmed. We can release the varieties through large population test, much earlier as the system provides conclusive information on varietal performance under field conditions thus reducing the intergeneration time interval in selection of varieties for commercialization.