Selection strategy in families of energy cane based on biomass production and quality traits

Abstract

The aim of this study was to identify the traits that most affect production of sugarcane, fiber and lignin content (LIG) with a view toward optimizing the process of assessment and selection of families of energy cane. Fifty full-sibs families were assessed using an incomplete-block design, with five replications. The traits assessed were mean stalk height (SH), mean stalk diameter (SD), mean number of stalks per plant (NS), mean stalk weight (SW), fiber content (FIB), LIG, tons of cane per hectare (TCH), tons of fiber per hectare (TFH) and tons of lignin per hectare (TLH). Based on path analysis, it was possible to observe that the traits SW and NS, in that order, exhibited the greatest direct effects on TCH, TFH, and TLH. These traits they were indirectly affected to a greater degree by NS. The direct effects of FIB, LIG, SH, and SD on TCH, TFH, and TLH were smaller than the residual effects on the analyses carried out, showing their little importance in the selection process. The increase of TFH and TLH mainly occur due to greater biomass production, which is associated with greater tillering capacity and with the SW of the families. Thus, selection of families with greater FIB might not show genetic gains if the mean values for TCH of their offsprings are low. Therefore, selection of the best families for energy cane should be carried out based on TCH, which may be estimated by way of NS and SW.