Polygenic inheritance of canopy wilting in soybean [Glycine max (L.) Merr.]

Theor Appl Genet. 2009 Aug;119(4):587-94. doi: 10.1007/s00122-009-1068-4. Epub 2009 May 27.

Abstract

As water demand for agriculture exceeds water availability, cropping systems need to become more efficient in water usage, such as deployment of cultivars that sustain yield under drought conditions. Soybean cultivars differ in how quickly they wilt during water-deficit stress, and this trait may lead to yield improvement during drought. The objective of this study was to determine the genetic mechanism of canopy wilting in soybean using a mapping population of recombinant inbred lines (RILs) derived from a cross between KS4895 and Jackson. Canopy wilting was rated in three environments using a rating scale of 0 (no wilting) to 100 (severe wilting and plant death). Transgressive segregation was observed for the RIL population with the parents expressing intermediate wilting scores. Using multiple-loci analysis, four quantitative trait loci (QTLs) on molecular linkage groups (MLGs) A2, B2, D2, and F were detected (P <or= 0.05), which collectively accounted for 47% of the phenotypic variation of genotypic means over all three environments. An analysis of the data by state revealed that 44% of the observed phenotypic variation in the Arkansas environments could be accounted for by these QTLs. Only the QTL on MLG F was detected at North Carolina where it accounted for 16% of the phenotypic variation. These results demonstrate that the genetic mechanism controlling canopy wilting was polygenic and environmentally sensitive and provide a foundation for future research to examine the importance of canopy wilting in drought tolerance of soybean.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Chromosome Mapping
  • Crosses, Genetic
  • Genetic Markers
  • Glycine max / genetics*
  • Glycine max / physiology*
  • Inbreeding
  • Multifactorial Inheritance / genetics*
  • Phenotype
  • Plant Leaves / genetics*
  • Plant Leaves / physiology*
  • Quantitative Trait Loci / genetics

Substances

  • Genetic Markers