ASSESSMENT OF BREEDING METHODS AND PARENTAL VALUE OF CO CANES DEVELOPED DURING 1918 - 2017

The performance of 1454 Co canes developed during 1918 to 2017 spanning one hundred years was assessed for nine contributing characters of cane yield and juice quality to identify the best and poorest Co canes and their parentages examined to assess the relative merit of different breeding methods adopted for their development as well as the parents responsible for their development. The study identified trait specific superior and inferior Co canes as well as Co canes superior for multiple traits. All quality traits and cane yield parameters, other than number of millable canes had a preponderance of recent selections under the best group, indicating that the genetic gain achieved in a century of breeding has been substantial. The biparental crosses accounting to 89.79 % of total Co canes is the best breeding method and highlighted the importance of specific combining ability in sugarcane improvement. On the contrary, only eleven female parents and 17 male parents bred more than 50 % of the best Co canes indicated the relevance of general combining ability, thus demonstrating the importance of both additive and non-additive variances in sugarcane. A fair number of proven parents and crosses for specific traits as well as for simultaneous enhancement of multitraits were identified offering the breeder an option to choose the parental combinations guided by the per se performance as well as their breeding value. The genetic gain achieved is being sustained with the addition of novel parental clones of diverse genetic background.