Genetic Variation and Postflowering Drought Effects on Seed Iron and Zinc in ICRISAT Sorghum Mini Core Collection uri icon

abstract

  • Drought stress invariably reduces yield and mayalter seed chemistry. This experiment was initiatedto characterize the sorghum (Sorghumbicolor (L.) Moench) mini core collection forgenetic variation and to study the effect of postfloweringdrought on seed Fe and Zn concentrations.Accessions with similar maturity, togetherwith controls, were evaluated in split-plot designunder irrigated and drought-stressed environmentsfor two postrainy seasons. Residual (orrestricted) maximum likelihood (REML) analysisof data considering genotypes as random anddrought and year as fixed indicated highly significantvariance as a result of genotypes. Highlysignificant effects of drought (D), year (Y), and Dx Y interaction emphasized need for multilocationevaluation of germplasm for agronomic andseed nutritional traits. About twofold variationin Fe (25.8?48.9 mg kg?1 seed) and threefoldvariation in Zn (13.5?42.6 mg kg?1 seed) concentrationswas observed across environments.Eleven accessions with high seed Fe, 14 accessionswith high Zn, and nine accessions high inboth Fe and Zn were identified. These accessions,however, produced low seed yields. Inaddition, six and four accessions, respectively,showed 8 to 39% and 9 to 38% greater Fe andZn over control IS 33844 and produced seedyields similar to that of IS 33844. Significantrank correlation (0.70) indicated that accessionswith high Fe or Zn under irrigated environmentsare also expected to perform well underdrought-stressed environments. Significantlypositive correlation between Fe and Zn indicatedsimultaneous improvement as a realisticapproach in breeding. The identified germplasmare ideal genetic resources for the developmentof Fe- and Zn-dense sorghum cultivars

publication date

  • 2016
  • 2016