Reference "Mapping QTLs and candidate genes for rice root traits under different water-supply conditions and comparative analysis across three populations"

Reference ID

8182

Title

Mapping QTLs and candidate genes for rice root traits under different water-supply conditions and comparative analysis across three populations

Source

Theoretical and applied genetics, 2003, vol. 107, pp. 1505-1515

Authors (8)

Zheng-B-S	Yang-L
Zhang-W-P	Mao-C-Z
Wu-Y-R	Yi-K-K
Liu-F-Y	Wu-P

Abstract

To investigate the genetic factors underlying constitutive and adaptive
morphological traits of roots under different water-supply conditions, a
recombinant inbred line (RIL) population derived from a cross between the
lowland rice variety IR1552 and the upland rice variety Azucena with 249
molecular markers, was used in cylindrical-pot experiments. Eighteen QTLs were
detected for seminal root length (SRL), adventitious root number (ARN), and
lateral root length (LRL) and lateral root number (LRN) on the seminal root at a
soil depth of from 3 to 6 cm under flooding and upland conditions. One identical
QTL was detected under both flooding and upland conditions. The relative
parameters under the two water-supply conditions were also used for QTL
analysis. Five QTLs for upland induced variations in the traits were detected
with the positive alleles from Azucena. A comparative analysis was performed for
the QTLs detected in this study and those reported from two other populations
with Azucena as a parent. Several identical QTLs for root elongation were found
across the three populations with positive alleles from Azucena. Candidate genes
were screened from ESTs and cDNA-AFLP clones for comparative mapping with the
detected QTLs. Two genes for cell expansion, OsEXP2 and endo-1,4-beta-D-
glucanase EGase, and four cDNA-AFLP clones from root tissues of Azucena, were
mapped on the intervals carrying the QTLs for SRL and LRL under upland
conditions, respectively.