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FUNAABOR-2 is a popular Ofada rice variety grown in a large area under rainfed upland condition across western states of Nigeria. We used the combination of phenotypic and marker-assisted selection (MAS) to improve grain yield of FUNAABOR-2 under drought stress (DS) at the reproductive stage via introgression of two drought quantitative trait loci (QTLs), qDTY12.1 and qDTY2.3. Foreground selection was carried out using peak markers RM511 and RM250, associated with qDTY12.1 and qDTY2.3, respectively, followed by recombinant selection with RM28099 and RM1261 distally flanking qDTY12.1. Furthermore, BC1F2-derived introgressed lines and their parents were evaluated under DS and non-stress (NS) conditions during the 2015–2016 dry season. Overall reduction of grain yield under DS compared to NS was recorded. Introgressed lines with qDTY12.1 and qDTY2.3 combinations showed higher yield potential compared to lines with single or no QTL under DS, indicating significant positive interactions between the two QTLs under the FUNAABOR-2 genetic background. Pyramiding of qDTY12.1 and qDTY2.3 in the FUNAABOR-2 genetic background led to higher grain yield production under DS and NS. Keywords: drought, foreground selection, introgressed line, peak marker, yield potential, rice, quantitative trait locus

The intermittent and widespread occurrence of drought in rainfed upland rice fields across sub-Sahara Africa has led to tremendous decrease in food security in the region. Although high yielding, drought tolerant varieties have been developed over years to mitigate this trend, limited adoption had been recorded for most of these materials. This study investigated farmers’ perceptions on drought stress and their preferred traits in new upland rice varieties across two major upland rice growing states in Nigeria. Participatory Rural Appraisal was conducted among 119 rice farmers using comparative approach, probing and semi structured interviews. Result based on farmers knowledge of changes in rainfall pattern and preferred traits such as plant architecture and grain shapes in a new upland rice variety differed significantly across the two state. The results identified drought stress as one of the main constraints to upland rice production across communities. The ideal upland rice variety desired by most respondents in both states should be of medium plant height (115-130cm) characterized by white, long and bold grains. This study has demonstrated the importance of understanding farmer’s desired traits in a new upland rice variety and the need to incorporate identified traits in creation of resilient new upland rice varieties adaptable to rain-fed upland rice growing regions of Nigeria.

Oryza glaberrima Steud, the indigenous domesticated Oryza species in West Africa, is a potential source of useful genes for a range of economically important characters. Progenies from interspecific hybridization of O. sativa and O. glaberrima show high sterility in the F1 hybrids and early generations. However, in some populations fertility was obtained(5-95%)and retained after two to four back-crossings. Although true intermediates between O. glaberrima and O. sativa were generally rare, their occurence in some populations was as high as 30%. Desirable morphological traits introgressed from O. glaberrima into segregating BC2 F3 populations included early maturity(75-100 days), rapid seedling growth and high tillering.