Breeding new sugarcane varieties with enhanced ratooning ability

摘要

Sugarcane crop-cycle length and yield are largely determined by the ratoon crops and drive economic returns for farming operations. A number of factors affect ratooning ability (RA the percent of the second-ratoon crop yield to the plant-cane crop yield). The transition from manual harvest to mechanized harvest in many industries has had a negative effect on RA, and most agree that the variety component is the key to improving RA. Thus, it is paramount that sugarcane breeding programs set RA as a high priority. Reported broad-sense heritabilities for RA are generally low; accordingly, some breeding programs employ family selection strategies to enhance selection. A few breeding programs have reported other useful statistics that have shaped selection strategies for RA, such as: genetic and genotype-by environment variance component structure; genetic advance values; genetic correlation among traits among crops. However, there is a general paucity of data driving the selection strategy for RA for many sugarcane breeding programs. Introgression breeding efforts have improved RA in some sugarcane industries and offer the necessary genetic variation to exploit through the selection process. The goal of this report is to detail the experiences and progress of sugarcane breeding programs for developing varieties with improved RA.