Establishment of evaluation procedure for soybean seed-flooding tolerance and its application to screening for tolerant germplasm sources

Abstract

The experiments concluded 48hrs for germination testing as most appropriate stress duration. Using paper roll for recording the traits was the best method than petri dish and towel method. Among the traits relative germination rate (RGR), relative seedling length (RSL), relative root length (RRL), relative root fresh weight (RRFW) and relative root dry weight (RRDW) were proved to be flooding-responsive. RSL was chosen as the major seed-flooding indicator due to higher heritability (h2), genotypic coefficient of variation (GCV), correlation with other indicators and easier measuring procedure, while RRL was considered as the subsidiary indicator. Thus, the RSL in paper roll after 48hrs seed-flooding was recognized as standard seed-flooding testing procedure and used to evaluate breeding materials. Among the 11 cultivars, the superior seed-flooding-tolerant ones were M8206, NN1138-2 and ZXD, while ten best lines were evaluated from one hundred breeding lines.