Multispectral Imaging and Genetic Analysis of Cultivated Chickpea Seed Traits
General Material Designation
[Thesis]
First Statement of Responsibility
Akhmetov, Zhaslan
Subsequent Statement of Responsibility
Cook, Douglas R
.PUBLICATION, DISTRIBUTION, ETC
Name of Publisher, Distributor, etc.
University of California, Davis
Date of Publication, Distribution, etc.
2019
GENERAL NOTES
Text of Note
43 p.
DISSERTATION (THESIS) NOTE
Dissertation or thesis details and type of degree
M.S.
Body granting the degree
University of California, Davis
Text preceding or following the note
2019
SUMMARY OR ABSTRACT
Text of Note
Multispectral Image Analysis of Cultivated Chickpea Seed Traits Cultivated chickpea (Cicer arietinum) is one of the world's most widely grown crops (FAO STAT 2014), with India, Australia, and Pakistan being the major producers of chickpea seeds. Genetic improvement of chickpea is constrained by low genetic diversity, resulting from a domestication and breeding bottleneck that removed >95% of genetic variation. Recently, wide-cross populations involving the domesticated species and its wild relatives, C. reticulatum and C. echinospermum, have been constructed as a pre-breeding resource (von Wettberg et al., 2018). Chickpea seed traits influence marketablitity and price. This project examined phenotypic variation and genetic control of seed coat traits (e.g., coat color and pattern) in wide cross F2 populations. Available evidence suggests that both color and pattern are the product of plant secondary metabolites, specifically flavonoid anthocyanins, produced in the maternal seed coat tissue. As seed coat color is a complex trait, seed coat reflectance was quantified using a multispectral imaging device to record nineteen wavelengths and the international standards for visual color CIE L*, a*, b*. Correlation analyses reduced this to a set of five minimally correlated wavelengths. Quantitative trait locus (QTL) mapping revealed a single major locus controlling seed patterning (spots) in both C. reticulatum and C. echinospermum, with the effect of additional epistatic loci observed but not genetically resolved. Seed coat reflectance is controlled by multiple loci. Two reflectance loci are operative across all analyzed populations, controlling near-infrared (780nm) and visual wavelengths, respectively, while several other loci were observed with population-specific effects. Analysis of genetic interactions suggests two networks of interacting genes operating to control seed coat reflectance.