Orange-fleshed sweet potato [Ipomoea batatas (L.) Lam] genotype by environment interaction for yield and yield components and SPVD resistance under arid and semi-arid climate of northern Ethiopia

Abstract

Worldwide, sweet potato (Ipomoea batatas (L.) Lam) ranks the sixth most important crop valued for food security, income, and nutritious diet for poor farming communities. Despite its importance, there is lack of information and knowledge to introduce the crop to Afar region where malnourishment is high. Six orange-fleshed sweet potato genotypes (Amelia, Erica, Gloria, Ininda, Kulfo, and Melinda were evaluated for sweet potato viral disease (SPVD), yield and yield components in three contrasting locations, namely Aba’ala, Mekelle 1, and Mekelle 2 using a Randomized Complete Block Design to produce variance components. Joint regression, and additive main effects and multiplicative interactions were used to test the Genotype × Location Interactions (GEI). Means for significant traits were separated by Least Significant Difference (p<0.05). Results showed ample genetic variability for total tuberous yield (TTY), and SPVD resistance. Genotypes Ininda, Gloria, Amelia, and Kulfo were superior for TTY with high SPVD resistance. Aba’ala was a hotspot for SPVD, Mekelle 2 was with low SPVD and recorded a high mean TTY. Amelia and Kulfo exhibited static stability, Ininda and Gloria displayed dynamic stability, high harvest index, and fresh vine yield, and were recommended for further stability investigations. The information generated in this study may be useful as preliminary data however, the experiment has to be repeated for practical conclusions and recommendation of stable varieties for the studied agro-climatic zones.