Genetic diversity and yields of promising sugarcane clones under ratoon crop in a rainfed land

This study examined the genetic diversity and yield of improved sugarcane clones in ratoon crops on rainfed land. Ten sugarcane clones (SB 01, SB 03, SB 04, SB 11, SB 12, SB 19, SB 20, and two control varieties, PS 881 and Bululawang) were evaluated during two ratoon cycles in East Java, Indonesia (7°27'28 "S 112°23'03 "E) from September 2021 to May 2023 with an alluvial soil type. The study employed a mixed model, specifically a multi-season randomized group design with one factor: clone, where ratoon represented the season and observed growth and production parameters. The analysis revealed significant genetic diversity among the clones in terms of stem length, stem diameter, productivity, and Brix characteristics. Productivity consistently increased in the second ratoon for all clones, with the highest increase in SB 11 (29.0%) and SB 04 (28.9%). Heritability values increased in the second ratoon cycle for most characters, mainly stem length (0.37 to 0.79), productivity (0.52 to 0.78), and Brix (0.69 to 0.95). Significant positive correlations were found between ratoon and productivity (0.70), rendemen (0.61), and Brix (0.32). Stem diameter was positively correlated with productivity (0.30), hablur (0.40) and Brix (0.34). Clones SB 01, SB 11, SB 12, SB 19, and SB 20 showed superior performance for growth and yield characters, with SB 01 achieving the highest sugar yield (12.3 tons.ha-1). This study provides essential information for sugarcane breeding programs to develop superior varieties with high productivity and stability in ratoon crops on rainfed land.