Reference "Quantitative trait loci for root-penetration ability and root thickness in rice: comparison of genetic backgrounds"

Reference ID

5295

Title

Quantitative trait loci for root-penetration ability and root thickness in rice: comparison of genetic backgrounds

Source

Genome ( National Research Council Canada ), 2000, vol. 43, pp. 53-61

Authors (7)

Zheng-H-G	Babu-R-C
Pathan-M-S	Ali-L
Huang-N	Courtois-B
Nguyen-H-T

Abstract

Drought is the major abiotic stress limiting rice (Oryza sativa) production and
yield stability in rainfed lowland and upland ecosystems. Root systems play an
important role in drought resistance. Incorporation of root selection criteria
in drought resistance improvement is difficult due to lack of reliable and
efficient screening techniques. Using a wax-petrolatum layer system simulated to
compacted soil layers, root traits were evaluated in a doubled haploid (DH)
population derived from the cross between 'IR64' and 'Azucena'. Twelve putative
QTLs (quantitative trait loci) were detected by interval mapping comprising four
QTLs for root-penetration ability, four QTLs for root thickness, two QTLs for
penetrated root number, and two QTLs for total root number. These QTLs
individually explained 8.4% to 16.4% of the phenotypic variation. No QTL was
detected for maximum penetrated root length by interval mapping. One QTL located
between RG104 and RG348 was found to influence both root-penetration ability and
root thickness. QTLs for root-penetration ability and root thickness were
compared across two populations, 'IR64'-'Azucena' and 'CO39'-'Moroberekan', and
different testing conditions. The identified consistent QTLs could be used for
marker-assisted selection for deep and thick roots with high root-penetration
ability in rice.