Potential and Advanced Strategies for Sugarcane improvement

Abstract

Modern sugarcane cultivars are characterized by high genetic complexity making traditional improvement extremely laborious, costly and time consuming. Several biotechnological tools applied at different stages of a classical breeding program can make the overall process more efficient. Exploration, conservation and utilization of genetic resources of sugarcane germplasm bank assisted by molecular markers allow to prevent possible erosion and to select a core collection maximizing allelic diversity. When new germplasm is incorporated, molecular techniques to detect systemic diseases during quarantine and tissue culture to sanitize diseased imported materials accelerate and guarantee the success of the process. Likewise, accessions genotypic information is useful to design the crosses according to the goals of the program. Once the crosses have been made, hybridity tests based on molecular markers allow identifying true hybrids of sugarcane. At the following clone selection stages, molecular markers linked to traits of interest are useful to increase the genetic gain rate. Genomic selection is under development in order to predict the genetic merit of clones more accurately by using next generation sequencing. Later, when a variety is going to be released to commercial cultivation, micropropagation techniques make it possible to provide producers with healthy and true-to-type seed cane. Varieties obtained are the starter material for crop improvement through genetic engineering (genetic transformation or genome editing) in order to add traits of interest for the breeding program. In summary, biotechnological tools applied to the conventional breeding scheme allow increasing the efficiency to obtain new outstanding varieties.