Marker-Assisted Introgression of Quantitative Resistance Gene pi21 Confers Broad Spectrum Resistance to Rice Blast

doi:10.1016/j.rsci.2020.01.002

Abstract

Abstract:

The quantitative resistance gene pi21 from Sensho was introgressed to an indica breeding line IR63307-4B-13-2, a pyramiding line IRBB4/5/13/21, and a tropical japonica line Kinandang Patong by marker-assisted backcrossing. A total of 192 improved lines at the BC₄F₃ and BC₄F₄ generations were developed and confirmed to have the gene introgression via genotyping using a pi21-specific InDel marker. Thirteen randomly selected improved lines, representing all the three genetic backgrounds, demonstrated resistance against leaf blast composites in the field and a broader spectrum resistance against individual isolates compared to the recurrent parents in the glasshouse. Specifically, the tested lines exhibited pi21-acquired resistance against 11 leaf blast isolates that elicited susceptible reactions from the recurrent parents. All the tested lines maintained a comparative heading date, and similar or improved panicle length, number of primary branches per panicle and number of total grains per panicle relative to the recurrent parents. The physical grain characteristics of the recurrent parents were also maintained in the 13 lines tested, although variability in the amylose content and chalkiness degree was observed. The successful marker-assisted introgression of pi21 in diverse genetic backgrounds and the resulting broader spectrum resistance of improved lines against leaf blast indicate the potential of pi21 for deployment in cultivars grown across other rice growing regions in Asia.

Key words: rice blast, pi21 gene, marker-assisted breeding, disease resistance

B. ANGELES-SHIM Rosalyn, P. REYES Vincent, M. del VALLE Marilyn, S. LAPIS Ruby, SHIM Junghyun, SUNOHARA Hidehiko, K. JENA Kshirod, ASHIKARI Motoyuki, DOI Kazuyuki. Marker-Assisted Introgression of Quantitative Resistance Gene pi21 Confers Broad Spectrum Resistance to Rice Blast[J]. Rice Science, 2020, 27(2): 113-123.

Figures/Tables 7

References 51

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Isolate name	Group^b	Subgroup^c	Philippine collection site
Ca89	I	b	Luzon and Mindanao islands
IK81-3	II	-	Southern Luzon island
M39-1-3-8-1	III	a	Southern Luzon island
V850256	III	c	Southern Luzon island
M64-1-3-9-1	III	a	Southern Luzon island
V86010	IV	e	Central and Southern Luzon island
BZ64-1	IV	-	unknown
BN111	V	a	Southern Luzon island
PO6-6	V	b	Southern Luzon island
M39-1-2-21-2	VI	b	Central and Southern Luzon island
JMB8401	XII	a	Southern Luzon island
43	XVIII	-	unknown
M36-1-3-10-1	XIX	b	Southern Luzon and Mindanao islands
9475-1-3	XX	-	unknown
BN209	XXII	a	Southern Luzon island
M101-1-2-9-1	XXII	a	Southern Luzon island
IK81-25	XXIII	-	unknown
JMB840610	XXIV	b	Southern Luzon island
5167-1	XIX	-	unknown
Pi9-G7-2K-1	-	-	-

Isolate name	Group^b	Subgroup^c	Philippine collection site
Ca89	I	b	Luzon and Mindanao islands
IK81-3	II	-	Southern Luzon island
M39-1-3-8-1	III	a	Southern Luzon island
V850256	III	c	Southern Luzon island
M64-1-3-9-1	III	a	Southern Luzon island
V86010	IV	e	Central and Southern Luzon island
BZ64-1	IV	-	unknown
BN111	V	a	Southern Luzon island
PO6-6	V	b	Southern Luzon island
M39-1-2-21-2	VI	b	Central and Southern Luzon island
JMB8401	XII	a	Southern Luzon island
43	XVIII	-	unknown
M36-1-3-10-1	XIX	b	Southern Luzon and Mindanao islands
9475-1-3	XX	-	unknown
BN209	XXII	a	Southern Luzon island
M101-1-2-9-1	XXII	a	Southern Luzon island
IK81-25	XXIII	-	unknown
JMB840610	XXIV	b	Southern Luzon island
5167-1	XIX	-	unknown
Pi9-G7-2K-1	-	-	-

Cultivar and line	Initial reading			Final reading
Cultivar and line	SES	DLA (%)	Phenotype	SES	DLA (%)	Phenotype
Lijiangxintuanheigu (LTH, susceptible control)	5.3	34	MR	ND	ND	S
CO39 (susceptible control)	7.1	60	S	8.2	80	S
IR65482-4-136-2-2 (resistant control)	1.4	1	R	1.6	1	R
Sensho	1.1	2	R	1.5	2	R
IR63307-4B0-B-2 (IR63307)	0.5	1	R	0.5	1	R
WISH110:1-1-11-12-1	1.0	1	R	1.0	1	R
WISH110:1-1-11-5-4	2.0	1	R	0.5	1	R
WISH110:2-5-2-1-1	1.0	1	R	0.5	1	R
WISH110:2-5-2-12-1	0.0	0	R	0.5	1	R
WISH110:2-5-2-22-1	0.5	1	R	0.5	1	R
IRBB4/5/13/21 (IRBB)	4.0	5	MR	5.0	15	MR
WISH48:1-3-1-1	2.0	1	R	2.0	1	R
WISH48:1-3-18-1	2.0	3	R	3.5	5	R
WISH48:1-3-2-1	1.0	1	R	1.0	1	R
WISH48:1-3-20-1	3.0	3	R	1.0	1	R
WISH48:1-3-21-1	1.0	1	R	2.0	1	R
Kinandang Patong (KP)	0.0	0	R	0.5	0	R
WISH40:1-3-16-11	0.0	0	R	0.5	0	R
WISH40:1-3-3-9	0.0	0	R	0.0	0	R
WISH40:1-3-7-7	0.0	0	R	0.0	0	R

Cultivar and line	Initial reading			Final reading
Cultivar and line	SES	DLA (%)	Phenotype	SES	DLA (%)	Phenotype
Lijiangxintuanheigu (LTH, susceptible control)	5.3	34	MR	ND	ND	S
CO39 (susceptible control)	7.1	60	S	8.2	80	S
IR65482-4-136-2-2 (resistant control)	1.4	1	R	1.6	1	R
Sensho	1.1	2	R	1.5	2	R
IR63307-4B0-B-2 (IR63307)	0.5	1	R	0.5	1	R
WISH110:1-1-11-12-1	1.0	1	R	1.0	1	R
WISH110:1-1-11-5-4	2.0	1	R	0.5	1	R
WISH110:2-5-2-1-1	1.0	1	R	0.5	1	R
WISH110:2-5-2-12-1	0.0	0	R	0.5	1	R
WISH110:2-5-2-22-1	0.5	1	R	0.5	1	R
IRBB4/5/13/21 (IRBB)	4.0	5	MR	5.0	15	MR
WISH48:1-3-1-1	2.0	1	R	2.0	1	R
WISH48:1-3-18-1	2.0	3	R	3.5	5	R
WISH48:1-3-2-1	1.0	1	R	1.0	1	R
WISH48:1-3-20-1	3.0	3	R	1.0	1	R
WISH48:1-3-21-1	1.0	1	R	2.0	1	R
Kinandang Patong (KP)	0.0	0	R	0.5	0	R
WISH40:1-3-16-11	0.0	0	R	0.5	0	R
WISH40:1-3-3-9	0.0	0	R	0.0	0	R
WISH40:1-3-7-7	0.0	0	R	0.0	0	R

Line name	Blast isolates
Line name	1^a	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20
LTH	3^b/S	3/S	0/R	3/S	4/S	4/S	3/S	4/S	3/S	3/S	5/S	5/S	3/S	5/S	5/S	5/S	5/S	5/S	4/S	4/S
CO39	4/S	3/S	2/R	4/S	4/S	4/S	3/S	4/S	4/S	3/S	5/S	5/S	4/S	4/S	4/S	5/S	5/S	5/S	4/S	0/R
IR65482-4-136-2-2	0/R	0/R	0/R	0/R	0/R	0/R	0/R	0/R	0/R	0/R	1/R	0/R	4/S	0/R	0/R	1/R	2/R	0/R	0/R	0/R
IR72	0/R	0/R	0/R	1/R	0/R	3/S	0/R	0/R	0/R	0/R	2/R	1/R	0/R	0/R	0/R	0/R	2/R	1/R	0/R	2/R
Sensho	0/R	1/R	0/R	4/S	2/R	1/R	1/R	1/R	3/S	3/S	2/R	2/R	1/R	0/R	2/R	4/S	2/R	1/R	1/R	0/R
IR63307	2/R	1/R	0/R	0/R	0/R	2/R	1/R	2/R	2/R	1/R	1/R	2/R	2/R	0/R	5/S	5/S	2/R	0/R	4/S	0/R
WISH 110:1-1-11-12-1	1/R	0/R	0/R	0/R	0/R	1/R	1/R	0/R	1/R	0/R	1/R	1/R	1/R	0/R	2/R	2/R	1/R	0/R	2/R	0/R
WISH 110:1-1-11-5-4	1/R	1/R	0/R	0/R	0/R	1/R	1/R	1/R	1/R	1/R	1/R	1/R	1/R	0/R	2/R	2/R	1/R	0/R	1/R	0/R
WISH 110:2-5-2-1-1	1/R	0/R	0/R	0/R	0/R	1/R	1/R	1/R	1/R	1/R	1/R	1/R	1/R	0/R	2/R	2/R	1/R	0/R	2/R	0/R
WISH 110:2-5-2-12-1	1/R	0/R	0/R	1/R	0/R	1/R	0/R	1/R	1/R	0/R	1/R	1/R	1/R	0/R	1/R	1/R	1/R	0/R	2/R	0/R
WISH 110:2-5-2-22-1	1/R	1/R	0/R	0/R	0/R	1/R	0/R	1/R	1/R	0/R	1/R	1/R	1/R	0/R	2/R	2/R	1/R	0/R	2/R	0/R
IRBB	2/R	3/S	1/R	4/S	0/R	2/R	3/S	2/R	0/R	0/R	5/S	0/R	4/S	4/S	2/R	4/S	5/S	5/S	0/R	0/R
WISH 48:1-3-1-1	1/R	1/R	0/R	3/S	0/R	1/R	1/R	0/R	0/R	0/R	2/R	0/R	1/R	2/R	1/R	4/S	4/S	2/R	0/R	0/R
WISH 48:1-3-18-1	1/R	1/R	0/R	3/S	0/R	2/R	2/R	1/R	0/R	0/R	2/R	0/R	1/R	2/R	1/R	4/S	4/S	3/S	1/R	0/R
WISH 48:1-3-2-1	1/R	1/R	1/R	1/R	0/R	0/R	1/R	1/R	0/R	0/R	2/R	0/R	1/R	1/R	0/R	3/S	3/S	2/R	0/R	0/R
WISH 48:1-3-20-1	1/R	2/R	1/R	4/S	0/R	2/R	1/R	1/R	0/R	0/R	3/S	0/R	1/R	1/R	1/R	4/S	4/S	3/S	0/R	0/R
WISH 48:1-3-21-1	1/R	1/R	0/R	3/S	ND	0/R	0/R	1/R	0/R	0/R	1/R	0/R	2/R	1/R	1/R	4/S	4/S	2/R	0/R	0/R
KP	1/R	2/R	0/R	3/S	4/S	1/R	1/R	2/R	4/S	3/S	3/S	5/S	1/R	2/R	4/S	2/R	3/S	1/R	4/S	0/R
WISH 40:1-3-16-11	1/R	0/R	0/R	2/R	2/R	1/R	0/R	1/R	1/R	0/R	2/R	2/R	0/R	1/R	2/R	1/R	2/R	1/R	3/S	1/R
WISH 40:1-3-3-9	1/R	1/R	0/R	2/R	2/R	1/R	0/R	1/R	1/R	2/R	1/R	2/R	0/R	1/R	2/R	1/R	1/R	1/R	1/R	0/R
WISH 40:1-3-7-7	1/R	0/R	0/R	1/R	0/R	1/R	1/R	0/R	2/R	1/R	1/R	2/R	0/R	1/R	2/R	1/R	1/R	1/R	1/R	0/R