Abstract

Experiments in acid sand culture, acid and neutral soil fields were carried out in 2003 with the objective of studying genetic variability and correlation among seedling and mature plant traits with a view of guiding breeders on appropriate selection options in breeding for aluminium/acid stress tolerant soybean in Nigeria. Genotypic variance was high for all the sand culture traits (root dry weight, shoot dry weight and relative root surface area), leading to the high heritability estimates of 77.85% to 83.72%. Genetic advance as a percentage of the mean (GA) was very high (85.51%-155.84%) for the sand culture traits. As expected, a better performance in terms of grain yield and yield components was observed for the neutral soil field compared to the acid soil field. However, higher heritability estimates were observed for the field traits measured on the acid soil field compared to the neutral soil field. Heritability estimates for the days to flowering and plant height were high (66.44%-79.63%) compared to the moderate heritability (47.42%-58.89%) observed for the number of pods/plant and grain yield on both soils. Conversely, the GA for days to flowering and plant height was lower (12.08%-26.49%) compared to the values (27.27%-41.56%) observed for number of pods/plant and grain yield on both fields. Higher genotypic and phenotypic coefficients of variation (GCV and PCV) were observed for the sand culture traits compared to the field traits. On the acid and neutral soil fields GCV and PCV values were lower for the days to flowering and plant height compared to the values observed for the number of pods/plant and grain yield, with highly significant correlation between/within the sand culture traits and the field traits. These results indicate that selection of soybean genotypes with high seedling root dry weight and relative root surface area in acid sand culture at 450 μM Al³⁺ will enhance progress in the selection of high yielding acid tolerant tropically adapted genotypes of soybean on acid soils of Nigeria.

This work is licensed under a Creative Commons Attribution 4.0 License.