First Attempt To Identify And Map QTLs Associated With Promiscuous Nodulation In Soybean

To inform possibility of conducting marker assisted breeding of promiscuous soybean varieties, this study used 92 F2 lines from biparental cross to identify QTLs associated with promiscuous nodulation in soybean. GBS; genotyping by sequencing platform was used to generate SNPs through the pipeline 2 in TASSEL 5.0, Bowtie2 version 2.2.8 for tag alignment, Beagle version 4.1 to impute missing SNPs and R-QTL package in R for QTL identification. Four nodulation traits were assessed viz number of nodules (NN), percent of effective nodules (NE), fresh weight and dry weight of nodules (NFW and NDW). Two QTLs were identified on chromosomes 10 and 13. Both QTLs were associated with NN, only QTL13 was associated NE and only QTL10 was associated with nodule weights. It was observed that NN, NFW and NDW shared QTL10 and NN and NE share QTL13 allowing hypothetize on the existence of pleiotropic genes in those those two regions. Over dominance effect was observed for QTL10 and non additive effect for QTL13. The paper recommend investigations be pursued to validate those QTLs and set foundation for marker assisted selection of promiscuous soybean varieties. Also these findings could serve as starting point for gene cloning to better understand nodulation trait in soybean.