Establishing modalities for commercial-based variety evaluation and review of relative cane variety composition in sugarcane plantations

Abstract
Coordinated commercial and trial based variety evaluation is compulsory to avoid sugarcane growers’ unexpected loss due to the pre- and post release variety performance discrepancies. This investigation was conducted to establish modalities for commercial based variety evaluation, estimating the general performance (Gp) and relative variety composition or proportion (RCV) of commercial varieties cultivated in Ethiopia. The cane, sugar and estimated recoverable sucrose yield (ERS) data of commercial varieties obtained from agricultural and factory operations datasets and the survey data were included and analyzed. Three modalities were established for commercial based variety evaluation, estimating GP and RVC of sugarcane varieties. Results from the analysis of variance revealed the existence of significant and complex interactions among the variety, crop cycle, cutting and harvest age effects. Its significance demonstrated the importance of specific crop management for a specific sugarcane variety cultivated in the respective sugarcane plantation and demands the revision of the existing crop management practices in all sugarcane plantations. Generally, the established models were adequate to evaluate variety yield performance, estimate GP and RVC of the varieties evaluated. The models developed to estimate the GP and RCV of varieties in a specific sugarcane plantation were original and are the major innovative parts of this investigation. The serious variety ranking changes across locations highlighted the existence of substantial genotype x environment interaction and signals the long year cultivated sugarcane varieties had specific environmental domains in Ethiopia. The inclusion of survey data (growers’ preference) in the present investigation was much helpful in the process of identifying appropriate variety rankings. Hence, we recommend active participations of sugarcane growers in future commercial and trial based variety evaluations. Moreover, we suggested that future research efforts involving commercial and trial based variety evaluation to adopt the established modalities as a guide to assure efficient and coordinated sugarcane variety evaluation program in Ethiopia.