Identification and Characterization of Putative Cassava Mutant Genotypes under Low-pH Hydroponic Conditions with Aluminum

Cassava is an important staple food and an alternative to rice that exhibits relative resilience to both abiotic and biotic stresses. The development of cassava genotypes through mutation breeding has been conducted by a research team from the Department of Agronomy and Horticulture, IPB University. Currently, approximately 10 putative mutant cassava genotypes of M1V14 have been obtained, including G6-2-15-1-1, G6-2-15-5-3, and G6-2-15-3-3, which have high leaf mineral content and substantial tuber yield. This research aimed to evaluate morphological responses and identify growth patterns of cassava mutant genotypes under low-pH conditions with aluminum. By comparing control plants with Al-treated plants. ‘Vamas-1’, ‘Gajah’ (wild type), and putative mutant G6-2-15-1-1, and G6-2-15-5-3 exhibited greater reduction in plant and root growth compared to the putative mutant G6-2-15-3-3. All genotypes showed varying degrees of growth inhibition at the highest Al treatment (6 mM), indicating differences in Al tolerance. Based on the PCA analysis, most root morphological traits and plant biomass were strongly associated with the putative mutant G6-2-15-3-3. In addition, traits such as root diameter, number, length, and biomass were characteristic of ‘Gajah’, whereas the number of shoots, time of shoot emergence, and leaf biomass were characteristic of ‘Vamas-1’. In addition, based on leaf biomass and basal root morphology, the putative mutant G6-2-15-3-3 shows potential as a new superior genotype with high leaf and tuber production, offering additional economic value. The development of this variety could serve as an alternative for farmers in developing countries, especially in Indonesia, to address the challenges posed by acidic soils with high aluminum content.