Adaptation of soybean to tropical environments for smallholder farmers
There are many traits that influence crop adaption to a new environment so that it can perform as a farmer would prefer. In these chapters, I have shown the influence of the genetic mechanisms behind pod shatter, days to flower, days to maturity, and height for soybean in a tropical environment. We developed two molecular tools to identify the allele status of Pdh1, a gene that influences shatter. Using those tools, we discovered that this genetic source of shatter susceptibility is still prevalent in African breeding materials and released varieties. I also contributed knowledge of the effects of the maturity genes E1, E2, E3 and ELF3 on days to flower and days to maturity. It was discovered that season length can be controlled by choice of the long juvenile trait ELF3 allele. Days to flower is influenced by E1 alleles in a j-1 background, and is influenced by E1, E2, and E3 in a j-x background in some cases. I also discovered that the determinate and indeterminate phenotypes do have different influences on height in this environment, but the gene Dt1 does not affect maturity. The next step is to conduct yield testing to understand how these traits influence yield. In addition, other alleles of ELF3 should be bred into different backgrounds to see if they influence different season lengths as well. Finally, the genetic source of the long juvenile trait in the current African released varieties need to be discovered. Taken together the future data combined with the data presented here can assist a local breeder in Africa to choose the germplasm they want to control their season length or protect yields from pod shatter and ultimately create a new, elite African variety.
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License.