An on-farm study was conducted to evaluate plant growth, tuber yield and stability of orange fleshed sweet potato (OFSP) genotypes in three agro-ecological zones of Malawi. The study sites were Maseya in Chikhwawa District representing low altitude areas with hot climate; Bunda in Lilongwe District representing medium altitude with warm climate and Bembeke in Dedza District representing high altitude areas with cool climate. Genotypes LU06/0527, LU06/0252, LU06/0428, LU06/0299, LU06/0258,

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... , Kenya and Zondeni were evaluated in the trials. At each location, three farmers conducted the trials laid out in a Randomized Complete Block Design with three replicates on each farmer's field. Analysis of variance on the main effects of genotypes and environments as well as Interaction Principal Component Analysis (IPCA) for the residual multiplication interaction between genotypes and environments were conducted. Results revealed significant differences in vine length, leaf area and tuber yield among the genotypes evaluated as well as across the trial sites. Genotype LU06/0428 produced the highest leaf area of 130.9 cm 2 followed by BV/009 with 97.7 cm 2 . LU06/0527 was the highest tuber yielding genotype with 20.7 t/ha. Stability analysis found that Zondeni was the most stable variety across the sites. Bunda was the highest tuber yielding and unstable site while Maseya was the lowest yielding and unstable site.