Yield and Yield Components Evaluation of Cassava (Manihot esculenta Crantz) Clones in Different Altitudes

The research was conducted at three levels of altitude i.e 80 m asl (Kediri), 530 m asl (Malang), and 800 m asl (Ponorogo). The purpose of this research was to evaluate cassava clones under three altitudes (80 m asl, 530 m asl, and 800 m asl) and to identify cassava clones that tolerant to low temperature zones at medium altitude in the tropics. Criteria that used for selection the best clone in different altitude were stress tolerance index (STI), stress susceptibility index (SSI), stress tolerance (TOL), mean productivity (MP), and yield stability index (YSI). The result showed that stress tolerance index (STI) and mean productivity (MP) were good criteria for selecting cassava clones that tolerant to higher altitude. Tuber yield loss at 530 m asl was 32%, while at 800 m asl was 86%, compared to tuber yield at 80 m asl. Malang 4 (G3) and CMM 03038-7 (G8) are adaptive clones to environment at medium altitude up to 800 m asl.