Drought-tolerant QTL qVDT11 leads to stable tiller formation under drought stress conditions in rice.
Drought is an important limiting factor for rice production, but the genetic mechanisms of drought tolerance is poorly understood. Here, we screened 218 rice varieties to identify 32 drought-tolerant varieties. The variety Samgang exhibited strong drought tolerance and stable yield in rain-fed conditions and was selected for further study. To identify QTLs for drought tolerance, we examined visual drought tolerance (VDT) and relative water content (RWC) phenotypes in a doubled haploid (DH) population of 101 individuals derived from a cross between Samgang and Nagdong (a drought-sensitive variety). Three QTLs from Samgang were identified for VDT and explained 41.8% of the phenotypic variance. In particular, qVDT11 contributed 20.3% of the phenotypic variance for RWC. To determine QTL effects on drought tolerance in rain-fed paddy conditions, seven DH lines were selected according to the number of QTLs they contained. Of the drought-tolerance-associated QTLs, qVDT2 and qVDT6 did not affect tiller formation, but qVDT11 increased tiller number. Tiller formation was most stable when qVDT2 and qVDT11 were combined. DH lines with both of these drought-tolerance-associated QTLs exhibited the most stable tiller formation. Together, these results suggest that qVDT11 is important for drought tolerance and stable tiller formation in rain-fed paddy fields.
Department of Southern Area Crop Science, National Institute of Crop Science, Rural Development Administration, Miryang 50424, Republic of Korea. Electronic address: kimth6148@korea.kr.
Tae-Heon
TH
Kim
Department of Southern Area Crop Science, National Institute of Crop Science, Rural Development Administration, Miryang 50424, Republic of Korea. Electronic address: millet@korea.kr.
Yeon-Jae
YJ
Hur
Department of Southern Area Crop Science, National Institute of Crop Science, Rural Development Administration, Miryang 50424, Republic of Korea. Electronic address: han0si@korea.kr.
Sang-Ik
SI
Han
Department of Southern Area Crop Science, National Institute of Crop Science, Rural Development Administration, Miryang 50424, Republic of Korea. Electronic address: hy4779@korea.kr.
Jun-Hyun
JH
Cho
College of Agriculture and Life Science, Kyungpook National University, Daegu 41566, Republic of Korea. Electronic address: kkm@knu.ac.kr.
Kyung-Min
KM
Kim
Research Policy Bureau, Rural Development Administration, Jeonju 54875, Republic of Korea. Electronic address: ccriljh@korea.kr.
Jong-Hee
JH
Lee
Department of Southern Area Crop Science, National Institute of Crop Science, Rural Development Administration, Miryang 50424, Republic of Korea. Electronic address: songyc@korea.kr.
You-Chun
YC
Song
Department of Southern Area Crop Science, National Institute of Crop Science, Rural Development Administration, Miryang 50424, Republic of Korea. Electronic address: yukwon@korea.kr.
Yeong-Up
YU
Kwon
Department of Southern Area Crop Science, National Institute of Crop Science, Rural Development Administration, Miryang 50424, Republic of Korea. Electronic address: jacob1223@korea.kr.
Dongjin
D
Shin
D000222:Adaptation, Physiological / Q000235:genetics*; D055864:Droughts; D017343:Genes, Plant; D014644:Genetic Variation; D005838:Genotype; D012275:Oryza / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D010641:Phenotype; D018547:Plant Stems / Q000254:growth & development* / Q000378:metabolism; D040641:Quantitative Trait Loci; D013312:Stress, Physiological / Q000235:genetics; D014867:Water / Q000378:metabolism
D014867:Water
Crop yield; Doubled haploid population; Drought; Vegetative growth stage