Effects on agronomic efficiency
All sugarcane varieties achieved poor (very low to negative) agronomic efficiencies regardless of N or K application rates, and the cropping systems (Table 2). All treatment effects and their interactions were not significant (Table 2). Similarly cropping systems were not significantly different in their agronomic efficiency (Table 2)
Effects on sugarcane quality (Pol % juice)
All sugarcane varieties reached their peak Pol % juice (sucrose content) at 19 MAP thereafter there was a steady reduction in sucrose content as the varieties approached 24 MAP regardless of the
cropping systems (Figure 5).