Maha Sarakham, located in Northeast Thailand, has become a traditionally recognized rainfed sugarcane (Saccharum spp. L.) cultivation land. The field experiment occurred in 2016–2017. Thirteen promising sugarcane lines, with three check cultivars and arranged in a randomized complete block design (RCBD), had four replications in two sites with low soil fertility and pH. Results indicated sugarcane genotypes considerably influenced all the parameters, with a significant variance between the studied locations. The genotype-by-location interactions were noteworthy for all traits, except stalk diameter, stalk weight, and millable canes. The cultivar Khon Kaen-3 (KK3) (72.77 and 60.71 t ha^-1) and genotype 91-2-527 (71.85 and 57.65 t ha^-1) produced the higher cane yields at both locations (L1 and L2, respectively). Additionally, the sugarcane genotypes 91-2-527, CSB06-4-12, MPT02-458, and KPS01-12 displayed higher stalk weights, while KK3 and TBy27-1385 yielded more millable canes. Genotype MPT02-458 exhibited superior plant height, cane yield, and commercial cane sugar (CCS) in highly acidic soil conditions. Meanwhile, 91-2-527 demonstrated a greater plant height at both sites (287.3 and 328.7 cm) and also showed higher CCS greater than 10 (11.6 and 11.9). These identified genotypes serve as a benchmark for Thailand’s sugarcane commercial system. The presented results suggested some sugarcane genotypes were appropriate for cultivation in acidic soil, with low fertility under rainfed conditions. The study recommends pursuing more investigation in identifying sugarcane genotypes potential for high yield and good ratoon ability.

Keywords: Sugarcane (Saccharum spp. L.), promising genotypes, yield components, sugar yield, CCS, acidic soil, rainfed conditions

Key findings: Sugarcane (Saccharum spp. L.) promising lines incurred evaluation in acidic soil with poor fertility in comparison with control types in plant canes. Genotypes KK3 and 91-2-527 produced the highest cane yield at both locations. Although, genotype 91-2-527 gave a lower CCS, however, it emerged greater than 10% of CCS. These sugarcane promising lines could be beneficial as germplasm to improve the cane production through breeding program.