Progress Made in Developing New High Yielding Potato Varieties for the Kenyan Highlands at KALRO-Tigoni

Breeding has been going on at Kenya Agricultural and Livestock Research Institute (KALRO), Tigoni in Kenya to develop high yielding potato varieties that have good processing qualities. The objective was to develop high yielding potato varieties that are adapted to the Kenyan climatic and environmental conditions and that are suitable for processing. After initial crossing, the resultant families were evaluated for yield as well as crisping and chipping quality for three consecutive generations at KALRO-Tigoni; this resulted in selection of 112 candidate clones. The 112 selected clones (52 potentially for crisping) were then evaluated under Advanced Yield Trials (AYT) during the 2015 short rains season and 2016 long rains season at three sites (Tigoni, Molo and Meru). Yield data was analysed using the lattice procedure of Statistical Analysis Systems (SAS 9.1) statistical package. Genotype x Environment Interaction (GEI) as well as stability and adaptability of potato clones across sites was analysed using additive main effects and multiplicative interaction (AMMI) and genotype main effect and Genotype x Environment Interaction (GGE) biplot analysis. In the AYT, significant Genotype x Environment Interactions (GEI) were observed. Clone G6 (2E87) was closest to the ideal genotype; it was the highest yielding and most stable while environment 2 (long rains season 2016 at KALRO-Tigoni) was the closest to ideal environment and therefore the most desirable of the six environments. From AYT, 18 clones were selected, 11 of them good for crisping. These clones were recommended for the National Performance Trials (NPT) before release of new varieties.