Lowland rice in Lao PDR is predominantly grown under drought-prone, rainfed conditions in the wet season. We utilised a farmer participatory variety selection (PVS) approach in combination with multi-location yield trials (MLTs) conducted in high- and low-toposequence positions to test advanced breeding lines with the aim of improving the efficiency of the rice-breeding program and encouraging rapid adoption of improved lines.
Upper position fields were utilised to screen for traits for unfavourable environments, including drought resistance, while lower fields were used to target yield potential. Yield was, on average, 13% lower in upper than lower (2.85 t/ha) field positions, and varieties adapted to high-toposequence position were identified. Farmer preference was not associated well with grain yield performance, with a significant positive relationship (r = 0.34*, n = 23) identified only in the Vientiane (VTN) low-toposequence trial; rather, the famers tended to choose lines they believed were best adapted to their own farm. Although a significant relationship existed for both farmer preference (r = 0.42*, n = 23) and grain yield (r = 0.50*, n = 23) in high and low toposequences across all provinces in 2010, this relationship was not significant in VTN, where the high position was low-yielding (1.2 t/ha). By utilising farmer preference information in combination with traditional MLT data, only lines agronomically acceptable to farmers were progressed into a seed-multiplication system for country-wide, farmer yield testing. Thus, the PVS-MLT approach has provided efficient delivery of highly acceptable lines to farmers, which directly contributes to improved efficiency of the rice-breeding program.