Quantifying genetic variability and genotype ranking for food quality attributes in white Guinea yam (Dioscorea rotundata) using a multiple trait selection index

Alice Adenike Olatunji^1,2*Andrew Saba Gana²Kehinde D Tolorunse²Ryo Matsumoto³Patrick Olusanmi Adebola¹Asrat Asfaw¹

• ¹International Institute of tropical Agriculture (IITA), Abuja, Nigeria, FCT, Abuja, Nigeria
• ²Federal University of Technology Minna, Minna, Niger, Nigeria
• ³International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria

Yield and food product quality are important attributes in yam (Dioscorea spp.) cultivar choice. Among the food products, boiled yam and pounded yam are traditional dishes that hold cultural, nutritional, and sensory significance in areas where yam is considered a staple food.This study evaluated starch, sensory, and textural attributes of boiled and pounded yam food products of twenty-five white Guinea yam (Dioscorea rotundata) genotypes grown in five environments. The sensory quality of both boiled and pounded yam products was assessed through sensory evaluation and an instrument-based textural profile assay (ITPA) was conducted on pounded yam.The environmental influence associated with cropping seasons and locations varied across traits, ranging from 1.4% (Adhesiveness) to 20.7% (Cohesiveness). Significant positive correlations (p<0.001) were recorded between overall acceptability of pounded yam and its aroma, taste, colour and appearance. Crude starch correlated positively (p<0.001) with instrumental gumminess, chewiness, and resilience but negatively with sensory texture highlighting the need for balanced starch content. Using Log odds ratio analysis method, TDr1741073 was identified as superior genotype likewise using multi-trait ideotype distance index (MGIDI) which expressed outstanding in both attributes making it good candidate for use as parent in breeding program.