Reference "Mapping of quantitative trait loci associated with ultraviolet-B resistance in rice ( Oryza sativa L.)"

Reference ID

7976

Title

Mapping of quantitative trait loci associated with ultraviolet-B resistance in rice ( Oryza sativa L.)

Source

Theoretical and applied genetics, 2003, vol. 107, pp. 1003-1008

Authors (5)

Sato-T	Ueda-T
Fukuta-Y	Kumagai-T
Yano-M

Abstract

The detection of quantitative trait loci (QTLs) associated with UV-B resistance
in rice should allow their practical application in breeding for such a complex
trait, and may lead to the identification of gene characteristics and functions.
Considerable variation in UV-B resistance exists within cultivated rice ( Oryza
sativa L.), but its detailed genetic control mechanism has not been well
elucidated. We detected putative QTLs associated with the resistance to enhanced
UV-B radiation in rice, using 98 BC(1)F(5) (backcross inbred lines; BILs)
derived from a cross between Nipponbare (a resistant japonica rice variety) and
Kasalath (a sensitive indica rice variety). We used 245 RFLP markers to
construct a framework linkage map. BILs and both parents were grown under
visible light with or without supplemental UV-B radiation in a growth chamber.
In order to evaluate UV-B resistance, we used the relative fresh weight of
aerial parts (RFW) and the relative chlorophyll content of leaf blades (RCC).
The BIL population exhibited a wide range of variation in RFW and RCC. Using
composite interval mapping with a LOD threshold of 2.9, three putative QTLs
associated with both RFW and RCC were detected on chromosomes 1, 3 and 10.
Nipponbare alleles at the QTLs on chromosome 1 and 10 increased the RFW and RCC,
while the Kasalath allele at the QTL on chromosome 3 increased both traits.
Furthermore, the existence of both QTLs on chromosomes 1 and 10 for UV-B
resistance was confirmed using chromosome segment substitution lines. Plants
with Kasalath alleles at the QTL on chromosome 10 were more sensitive to UV-B
radiation than plants with them on chromosome 1. These results also provide the
information not only for the improvement of UV-B resistance in rice though marker-
associated selection, but also for the identification of UV-B resistance
mechanisms by using near-isogenic lines.