Improvement of Drought Tolerance in Rice (Oryza sativa L.): Genetics, Genomic Tools, and the WRKY Gene Family

Table 1

The QTLs identified for drought tolerance-related traits in rice.

Traits	Number of QTLs	Chromosome/linkage group	Explained Phenotypic variation (%)	Reference
Osmotic adjustment	1 (OA70)	8	Major	[21]
Drought avoidance	17	All except 9	4.4–25.6	[22]
Root traits	18	All chromosomes	1.2–18.5	[23]
Root and related traits	42	All chromosomes	6.0–24.4	[24]
Water stress indicators, phenology and production traits	47	All except 5	5.0–59.0	[25]
Grain yield and other agronomic traits	77	All except 12	7.5–55.7	[26]
Basal root thickness and 100-grain weight	2	4, 6	20.6–33.4	[27]
Coleoptile length and drought resistance index	15	All except 3, 8, 11	4.9–22.7	[28]
Relative growth rate and specific water use	7	2, 4, 5, 6, 7, 8	10.0–22.0	[29]
Grain yield	1(qtl12.1)	12	51.0	[30, 31]
Grain yield	2	2, 3	13.0–31.0	[32]
Grain yield	1(qDTY12.1)	12	23.8	[33]
Grain yield	1(qDTY3.2)	3	23.4	[34]
Grain yield	14	All except 9, 11	13.3	[35]
Filled grain number per panicle	23	All except 12	33.3	[35]
Panicle number per plant	14	All except 1, 3, 8	_	[35]
1000-grain weight	21	All except 12	50.3	[35]
Grain yield (under drought stress)	1(qDTY2.3)	2	9.0	[36]
Grain yield (under drought stress)	1(qDTY2.2)	2	6.0	[36]
Grain yield	4	3	18.8-31.8	[37]
Physio-morphological	9	4	36.8	[38]
Plant production	24	1,6	14-20.9	[38]
Grain yield	7	1, 2, 3, 9, 12	31-77	[39]