evaluation of resistance genes in rice against local isolates of xanthomonas oryzae pv. oryzae in...

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Evaluation of resistance genes in riceagainst local isolates of Xanthomonasoryzae pv. oryzae in Punjab Province ofPakistanJunaid Ahmed Khan a , Hafiz Muhammad Imran Arshad a ,Kamran Saleem a , Ahmed Faraz Sandhu a , Shahida Hasnain b &Muhammad Masood Babar aa Plant Protection Division , Nuclear Institute for Agriculture andBiology (NIAB) , PO Box 128, Jhang Road, Faisalabad , Pakistanb Department of Microbiology and Molecular Genetics , Universityof the Punjab , Lahore , PakistanPublished online: 07 Aug 2012.

To cite this article: Junaid Ahmed Khan , Hafiz Muhammad Imran Arshad , Kamran Saleem ,Ahmed Faraz Sandhu , Shahida Hasnain & Muhammad Masood Babar (2012) Evaluation ofresistance genes in rice against local isolates of Xanthomonas oryzae pv. oryzae in PunjabProvince of Pakistan, Archives Of Phytopathology And Plant Protection, 45:15, 1826-1839, DOI:10.1080/03235408.2012.712830

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Evaluation of resistance genes in rice against local isolates of

Xanthomonas oryzae pv. oryzae in Punjab Province of Pakistan

Junaid Ahmed Khana, Hafiz Muhammad Imran Arshada, Kamran Saleema*,Ahmed Faraz Sandhua, Shahida Hasnainb and Muhammad Masood Babara

aPlant Protection Division, Nuclear Institute for Agriculture and Biology (NIAB), PO Box 128,Jhang Road, Faisalabad, Pakistan; bDepartment of Microbiology and Molecular Genetics,University of the Punjab, Lahore, Pakistan

(Received 4 July 2012; final version received 5 July 2012)

Absence of resistance/tolerance against bacterial leaf blight (BLB), incited byXanthomonas oryzae pv. oryzae, in famous basmati varieties is one of the mainreason for BLB epidemic in Punjab in 2007–2008. For developing resistanceagainst BLB, the response of 26 IRBB lines of IRRI including 10 near isogeniclines (NILs) and 16 gene pyramids carrying two to five resistance genes (Xa series)was evaluated against 61 indigenous Xoo isolates under artificial inoculation fieldconditions. None of the NILs or gene pyramid provides complete protectionagainst all the isolates. However, Xa21 and xa13 were found resistant against themajority of Xoo isolates, followed by Xa14 and Xa7. Of the 16 gene pyramidsused in this study, IRBB-54 (Xa5 þ Xa21), IRBB-55 (Xa13 þ Xa21) followed byIRBB-58 (Xa4 þ Xa13 þ Xa21) were found effective against the majority of theXoo isolates. These resistance genes (individually and in combinations) can beincorporated for the improvement of basmati rice cultivars cultivated in Punjabprovince of Pakistan. Effectiveness of gene combination supports the strategy ofpyramiding appropriate resistance genes. Newly identified resistant genes mayalso be evaluated for achieving broad spectrum resistance against more Xooisolates of the area.

Keywords: Xa genes; BLB; rice NILs; rice pyramids; BLB resistant genes

Introduction

Rice (Oryza sativa L.), a member of the family Graminae is a staple food of over2.7 billion people worldwide, but its production is constrained by diseases offungal, bacterial and viral origin. Bacterial leaf blight (BLB) of rice incited byXanthomonas oryzae pv. oryzae (Xoo) (Swings et al. 1990) is one of the oldestknown diseases and was first noticed by the farmer of Japan in 1884 (Onasanyaet al. 2009). Bacterial leaf blight is the most destructive disease which is prevalentin the major rice growing countries of Asia (Wang et al. 2006). Introduction andcultivation of high yielding but susceptible rice cultivars was a major reason ofBLB in Asia (Onasanya et al. 2009). The disease occurred in both dry and wetseasons and affected rice plants at any growth stage, under tropical conditions

*Corresponding author. Email: [email protected]

Archives of Phytopathology and Plant Protection

Vol. 45, No. 15, September 2012, 1826–1839

ISSN 0323-5408 print/ISSN 1477-2906 online

� 2012 Taylor & Francis

http://dx.doi.org/10.1080/03235408.2012.712830

http://www.tandfonline.com

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(Suparyono et al. 2004). Approximately 90% of the rice in the world is grown inthe Asian continent (Salim et al. 2003), and Pakistan is the third largest basmatiexporter (Naveed et al. 2010). Bacterial leaf blight was first recorded in Pakistanby Mew and Majid (1977) and afterwards in 1987, its occurrence was confirmedfrom all the provinces of Pakistan (Akhtar et al. 2003). It has been observedduring recent years that the incidence of BLB disease is increasing in Pakistan,especially in ‘Kaller’ belt which is famous for rice cultivation (Khan et al. 2000).The presence of BLB disease in epidemic form was observed in some areas ofnorthern and central Punjab during 2006 and 2007 (Khan et al. 2008). Chemicalcontrol is not effective to control this disease under severe condition. The varietalresistance is the main control strategy economically effective and eco-friendly forthe management of this disease (Yamamoto et al. 1977). Globally, 34 Xa genesconferring resistance against Xoo have been identified so far (Chen et al. 2011).However, the durability of resistance depends upon the prevalence of pathogenraces in time and space.

Although a lot of research has been done on the evaluation of rice genotype(Khan et al. 2009), virulence reaction of local Xoo isolates (Mannan et al. 2009) andmolecular screening of local germplasm against a specific R gene (Abbasi et al. 2011)in Pakistan, for the development of durable-resistant cultivar, it is of primeimportance to screen all available resistant genes either single or in combinationagainst indigenous Xoo isolates. This study is an effort to evaluate genes and genecombinations which may be used for developing new varieties with genes conferringresistance to the bacterial blight.

Table. 1. Isolates of Xanthomonas oryzae pv. oryzae, no. of isolates, location and year ofcollection used for evaluation of IRBB lines in Punjab.

S no. IsolatesNo. ofisolates District Year

1 Xoo 1.3, Xoo 2.1, Xoo 41.3, Xoo 116.3, Xoo117.3, Xoo 123.6, Xoo 21.2-10, Xoo 68.4

8 Sheikhupura 2009–10

2 Xoo 4, Xoo 13.2, Xoo 15.1, Xoo 64.1, Xoo14.3, Xoo NIAB-1, Xoo 1.0-2010, Xoo102.8

8 Faisalabad 2009–10

3 Xoo 10.1, Xoo 66.4, Xoo 67.3, Xoo 68.1 4 Nankana 2009–104 Xoo 16.3, Xoo 17.1 2 Chiniot 2009–105 Xoo 18.3, Xoo 21.2-09, Xoo 22.4, Xoo 37.2,

Xoo 38.2, Xoo 67.7, Xoo 67.8, Xoo 84.48 Hafizabad 2009–10

6 Xoo 23, Xoo 25.2, Xoo 28.4, Xoo 86.6,Xoo 87.4, Xoo 87.6, Xoo 88.2, Xoo 88.12

8 Gujarat 2009–10

7 Xoo 32.2, Xoo 33.2, Xoo 43.5, Xoo 48,Xoo 49.3, Xoo 55.2

6 Gujranwala 2009–10

8 Xoo 59.8, Xoo 59.13, Xoo 61.2 4 Sialkot 2009–109 Xoo 77.2, Xoo 76.3 2 Okara 2009–1010 Xoo 80.3, Xoo 81.3, Xoo 82.2, Xoo 83.2, Xoo

85.15 Sahiwal 2009–10

11 Xoo 89.2, Xoo 89.7, Xoo 90.8 3 Mandibahuddin 2009–1012 Xoo 78.1 1 Pakpatan 2009–1013 Xoo 32 1 Vehari 2009–1014 Xoo 33.3 1 Bahawalpur 2009–10

Total 61 14

Archives of Phytopathology and Plant Protection 1827

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Table

2.

Ricelines

including10NIL

sand16pyramidsevaluatedforbacterialblightresistance

inPunjab.

IRBBlines

Xagenes

Source

Category

IRBB

lines

Xagenes

Source

Category

IRBB-1

Xa1

IRRI

NIL

IRBB-54

Xa5,Xa21

IRRI

Pyramid

IRBB-3

Xa3

IRRI

NIL

IRBB-55

Xa13,Xa21

IRRI

Pyramid

IRBB-4

Xa4

IRRI

NIL

IRBB-57

Xa4,Xa5,Xa21

IRRI

Pyramid

IRBB-5

Xa5

IRRI

NIL

IRBB-58

Xa4,Xa13,Xa21

IRRI

Pyramid

IRBB-7

Xa7

IRRI

NIL

IRBB-59

Xa5,Xa13,Xa21

IRRI

Pyramid

IRBB-10

Xa10

IRRI

NIL

IRBB-60

Xa4,Xa5,Xa13,Xa21

IRRI

Pyramid

IRBB-11

Xa11

IRRI

NIL

IRBB-61

Xa4,Xa5,Xa7

IRRI

Pyramid

IRBB-13

Xa13

IRRI

NIL

IRBB-62

Xa4,Xa7,Xa21

IRRI

Pyramid

IRBB-14

Xa14

IRRI

NIL

IRBB-63

Xa5,Xa7,Xa13

IRRI

Pyramid

IRBB-21

Xa21

IRRI

NIL

IRBB-64

Xa4,Xa5,Xa7,Xa21

IRRI

Pyramid

IRBB-50

Xa4,Xa5

IRRI

Pyramid

IRBB-65

Xa4,Xa7,Xa13,Xa21

IRRI

Pyramid

IRBB-51

Xa4,Xa13

IRRI

Pyramid

IRBB-66

Xa4,Xa5,Xa7,X

a13,Xa21

IRRI

Pyramid

IRBB-52

Xa4,Xa21

IRRI

Pyramid

IR-24

Susceptible

check

IRRI

Pyramid

IRBB-53

Xa5,Xa13

IRRI

Pyramid

NIL

,nearisogenic

lines;IR

RI,internationalrice

researchinstitute.

1828 J.A. Khan et al.

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Material and methods

Rice lines

Seeds of 10 NILs carrying single bacterial blight resistant gene, 16 pyramids havingresistant genes in different combinations (Table 1) and IR-24 as susceptible checkwere provided by CM Vera Cruz from the International Rice Research Institute(IRRI), Philippines. Seeds were broadcasted on dry land (raised beds, 1 ft. 6 1 ft.for each entry with 1 ft. interval), patted with bare hands and a thin layer of finecrushed decayed farmyard manure (FYM) was spread over them, covered withwheat straw and then watered with a hand sprinkler thrice a day. The nursery wasflooded for the first time after the fourth day of sprouting. On the 40th day, the plantswere transplanted having 9 inches plant to plant and 18 inches row to row distance.

Inoculum preparation

The 61 isolates of Xoo isolated from the diseased samples of rice representing 14districts of Punjab (Table 2) were incubated in potato sucrose agar (PSA) slants at308C for 48 hours in a shaker incubator. The 2-day-old cultures were then used toprepare inoculum by suspending separately the bacterial cells of each isolate in 10 mlof sterile distilled water and adjusting the concentration up to 108 colony formingunits (CFU)/ml.

Inoculation

Split plot design was used to test the virulence of bacterial isolates on the nearisogenic rice lines in which the isogenic lines were considered as the main plot andbacterial isolates as subplots (Gomez and Gomez 1984). Experimental unit consistedof three plants per isolate inoculation (Adhikari et al. 1999a). Three plants of eachisogenic line were inoculated with each of the 61 isolates of X. oryzae pv. oryzaeusing a clip inoculation method at maximum tillering stage (Kauffman et al. 1973).Three plants of IR-24 were also inoculated with each isolate as a susceptible check.

Disease assessment

The lesion length from the cut leaf tip was measured in centimetres (cm) at 18 daysafter inoculation. The disease reaction on the basis of lesion length (cm) wasclassified following Cottyn and Mew (2004) scale according to which 55 cm lesionlength is resistant (R), 5–10 cm as moderately resistant (MR), 10–15 cm asmoderately susceptible (MS) and 415 cm as susceptible (S).

Results

Behaviour of NILs against Xoo isolates

The response of 10 NILs against 61 Xoo isolates representing 14 zones of Punjab wasvery diverse in their reaction (Table 3). None of the NILs showed completeresistance to all the isolates. IRBB-21 and IRBB-13 carrying Xa-21 and Xa-13 genesrevealed high level of resistance against maximum isolates, i.e. 31 isolates followedby IRBB-14, IRBB-3, IRBB-1 and IRBB-7 carrying Xa14, Xa3, Xa1 and Xa7genes conferring resistance against 29, 26, 22 and 20 isolates, respectively. IRBB-5,


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Table

3.

Reactionof10nearisogenic

lines

carryingdifferentresistance

genes

against

61isolatesofXanthomonasoryzaepv.oryzaein

Punjab.

Isolates

IRBB-1

IRBB-3

IRBB-4

IRBB-5

IRBB-7

IRBB-10

IRBB-11

IRBB-13

IRBB-14

IRBB-21

Xoo1.3

SS

SS

MR

SS

SMR

MR

Xoo2.1

SS

SS

MS

MS

MS

SMR

MR

Xoo4

SMR

SS

MR

SS

RR

RXoo10.1

RR

SS

RS

SR

RR

Xoo13.2

MR

RS

SMR

SS

RR

RXoo15.1

MS

MR

SS

MS

SS

MR

RR

Xoo16.3

MS

RS

SMR

SS

RR

RXoo17.1

MR

MS

SS

MR

MR

MR

RR

RXoo18.3

RR

SS

RS

SR

RR

Xoo21.2-09

RMR

SS

MS

SS

RMR

RXoo22.4

RR

SS

RS

SR

RR

Xoo23

RMR

SMS

RS

SR

RR

Xoo25.2

RR

MS

MS

RMS

MS

RR

MR

Xoo28.4

RR

MS

MR

MR

SMR

RR

RXoo38.2

MR

MR

SS

MR

SS

MR

MR

MR

Xoo41.3

MR

RS

SR

MR

SR

RR

Xoo48

RR

SMS

MR

MS

MR

RR

MR

Xoo49.3

RR

MR

SR

SMR

RR

RXoo61.2

RMR

MS

MR

MR

SMR

MR

RMR

Xoo64.1

RR

MR

SR

SMR

RMR

RXoo66.4

MR

RS

SMR

MR

SMR

MR

RXoo67.3

RR

SS

MR

SS

RR

RXoo68.1

RR

SS

MR

MS

MS

MR

MR

MR

Xoo77.2

RMR

SS

MR

SS

RR

RXoo78.1

RR

SS

MR

SS

RR

RXoo80.3

MR

RS

SR

MR

SR

RR

Xoo81.3

MR

RS

SMR

MR

MS

RR

MR

Xoo82.2

MR

RS

SR

MR

MR

RR

RXoo112.3

RR

SS

RS

MR

RR

RXoo116.3

MR

RMS

MR

RS

SR

RR

Xoo117.3

MR

MR

SMR

MR

SS

RR

RXoo123.6

RR

SS

RMR

MR

MR

MR

R

(continued)


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Table

3.

(Continued).

Isolates

IRBB-1

IRBB-3

IRBB-4

IRBB-5

IRBB-7

IRBB-10

IRBB-11

IRBB-13

IRBB-14

IRBB-21

Xoo14.3

RMR

MS

MR

MR

MR

MR

RR

RXoo32.2

MR

RS

MS

MR

MS

MR

RR

RXoo33.2

MR

RMR

MR

RMR

MR

RMR

RXoo37.2

MR

MR

SS

RS

SR

MR

RXoo76.3

RMR

SS

MR

MS

MS

RR

MR

Xoo83.2

RR

SS

RMS

MR

MR

MR

RXoo85.1

RR

SS

RMR

MR

RMR

MR

XooNIA

B-1

RMR

MR

SMR

MS

MS

MR

RMR

Xoo1.0-2010

MR

RS

SR

SS

RR

RXoo21.2-10

SS

SMS

MR

MR

SS

MR

MR

Xoo32

SMR

SS

MR

MS

MS

SMR

MR

Xoo33.3

MS

SS

MS

MR

SMS

MS

MR

SXoo43.5

MS

SS

SS

SS

SS

MS

Xoo55.2

SS

SS

SS

MS

SS

SXoo59.8

SMS

MR

MS

MS

SS

SMS

MR

Xoo59.13

MS

MS

SMS

SMS

SMS

SMR

Xoo67.7

MR

SMR

MS

MR

MS

MR

SMR

MS

Xoo67.8

MS

MS

MS

RR

RR

MR

SMS

Xoo68.4

SMS

MR

MR

MR

MR

MR

MR

SMR

Xoo84.4

MS

MS

SMS

MR

MS

SMS

MR

MR

Xoo86.6

MR

MR

MS

MS

MR

MR

MS

MR

MR

MR

Xoo87.4

SMS

MS

MR

MR

MR

SMS

MR

SXoo87.6

SMS

MS

MS

RMR

MR

MS

MR

MR

Xoo88.2

MS

MS

MR

MR

MR

MS

SMS

SMR

Xoo88.12

MR

MS

MR

SMS

SMS

MR

MR

MR

Xoo89.2

SMS

MS

MS

MS

SMR

SMR

MS

Xoo89.7

MS

MR

SMS

MR

MS

MR

MR

MS

MR

Xoo90.8

MS

MS

MR

MR

MR

MR

MR

MS

SS

Xoo102.8

MR

MS

MR

MR

MR

MS

MS

MR

SS

RandMR

responses

R¼

22;

MR¼

18

R¼

26;

MR¼

15

R¼

0;

MR¼

11

R¼

1;

MR¼

11

R¼

20;

MR¼

32

R¼

1;

MR¼

16

R¼

1;

MR¼

20

R¼

31;MR¼

14

R¼

29;

MR¼

22

R¼

31;

MR¼

22

R,resistant(5

5cm

lesionlength);MR,moderately

resistant(5–10cm

lesionlength);MS,moderately

susceptible

(10–15cm

lesionlength);S,susceptible

(415cm

lesion

length).R

andMR

responseshavebeenshownwithbold

letters.


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IRBB-10 and IRBB-11 have resistant behaviour against single isolate while IRBB-4has no resistance against any isolate. IRBB-7 behaves moderately resistant againstmaximum isolates, i.e. 32 followed by IRBB-21 and IRBB-14 showing moderatelyresistance against 22 isolates. IRBB-11, IRBB-1, IRBB-10, IRBB-3, IRBB-4 andIRBB-5 showed MR response against 20, 18, 16, 15, 11 and 11 isolates, respectively.The rest of isolates has a compatible reaction against all NILs. IRBB-13 whichshowed resistance against maximum isolates has moderately resistance behaviouragainst only 14 isolates.

Behaviour of pyramids against BLB isolates

In the case of 16 rice pyramids, the high level of resistance was observed in IRBB-58carrying three resistant genes (Xa4, xa13 and Xa21) (Table 4). IRBB-58 has resistantpotential against 32 isolates and moderately resistant against 22 isolates. Among thesix rice pyramids having combination of two genes, resistance against maximumisolates was observed in IRBB-54, having combination of xa5 and Xa21, followed byIRBB-55 (xa13, Xa21), IRBB-52 (Xa4, Xa21), IRBB-51 (Xa4, Xa13) and IRBB-50(Xa4, Xa5) resistant against 30, 29, 25, 24 and 20 isolates, respectively. IRBB-50 hasgood response showing MR reaction against 29 isolates followed by IRBB-51,IRBB-54, IRBB-52 and IRBB-55. The rest of isolates has a compatible reaction withthese six pyramids having two gene combinations.

In six rice pyramids having a combination of three genes, the performanceof IRBB-58 was best followed by IRBB-57, IRBB-61 and IRBB-63. IRBB-62 andIRBB-59 behave in the similar way having no resistance against any Xoo isolates.IRBB-57 has MR reaction against maximum isolates. Three rice pyramids have acombination of four genes among which the performance of IRBB-60 was bettershowing resistance against four isolates, MR against 26, MS against 23 andcompatible against eight isolates. IRBB-64 showed resistance against three isolates,MR against 25, MS against 19 and susceptible against 14 isolates followed by IRBB-65. IRBB-66, a rice pyramid having combination of five genes, has resistance againstonly one isolate, MR against 22, MS against 28 and susceptible against 11 isolates.Susceptible check (IR-24) reaction was compatible against all the isolates.

Discussion

Until now, 34 BB resistant (R) genes have been identified and mapped (Chen et al.2011). Most of the R genes have been incorporated into the background ofsusceptible indica cultivar IR24 to develop a set of NILs and some have beenpyramided, either through classical breeding and marker assisted selection orthrough genetic engineering, to develop new plant types and NILs (Sanchez et al.2000; Singh et al. 2001; Narayanan et al. 2002). Deployment of resistant cultivarscarrying major resistant genes has been the most effective approach for the control ofBB, but for the incorporation of the most efficient gene, it is a pre-requisite toevaluate the resistant sources against existing races or isolates of Xoo. Five races ofXoo were identified in Pakistan and named as PKX1, PKX2, PKX3, PKX4 andPKX5 where PK stands for Pakistan and X stand for X. oryzae pv. oryzae (Mannanet al. 2009). In this study, we evaluated 26 rice differentials developed by IRRI,having different major genes or genes combination, against 61 isolates of Xoorepresenting 14 different zones of rice growing areas in Punjab (Pakistan). Disease


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Table

4.

Reactionsofthe16pyramidinglines

carrying2–5resistance

genes

against

61isolatesofXanthomonasoryzaepv.oryzaein

Punjab.

Isolates

IRBB

-50

IRBB

-51

IRBB

-52

IRBB

-53

IRBB

-54

IRBB

-55

IRBB

-57

IRBB

-58

IRBB

-59

IRBB

-60

IRBB

-61

IRBB

-62

IRBB

-63

IRBB

-64

IRBB

-65

IRBB

-66

IRBB

-24

Xoo1.3

SMR

MR

MR

MR

MR

MR

RS

SS

SS

SS

SS

Xoo2.1

RMR

MR

RMR

RMS

MR

SS

SS

SS

SS

SXoo4

RR

RR

RR

MR

MR

MS

MS

MS

SMR

MS

SS

SXoo10.1

MR

MR

MR

MR

MR

MR

MR

RMS

MR

SS

SS

SS

SXoo13.2

RMR

RR

RR

MR

RS

MS

SS

SMS

MS

SS

Xoo15.1

MR

RMR

MR

RR

MR

MR

SMS

SS

MS

MS

SS

SXoo16.3

SR

MR

RMR

MR

MS

RS

MS

MS

SMR

SMS

MS

SXoo17.1

MR

RMR

RMR

RMR

RMR

SS

SMS

SMS

SS

Xoo18.3

MR

RR

RR

MR

RMR

SS

SS

MS

SS

MS

SXoo21.2-09

MR

MR

RMR

MR

MS

MS

MR

MS

MS

MS

SMS

SMS

MS

SXoo22.4

RR

RMR

MR

MR

MR

MR

MS

MS

MS

SMR

SMR

MR

SXoo23

RR

RR

RR

RR

SS

MS

SMS

SMS

MS

SXoo25.2

MR

MR

RR

RMR

RR

MR

MR

MR

SMS

SMR

MS

SXoo28.4

RMR

RMR

RR

RR

MR

MR

MS

SMS

MR

MS

MS

SXoo38.2

MR

RR

RR

RR

RMS

MR

SS

MS

SMS

MR

SXoo41.3

RR

RMR

RMR

MR

RMS

MR

MS

SMR

MS

MS

MS

SXoo48

MR

RR

RR

RR

RMR

MS

MS

SMS

MS

SS

SXoo49.3

RMR

MR

MR

RR

MR

RS

MS

MR

SMR

MR

MR

SS

Xoo61.2

RR

RR

RR

RR

MS

MR

MR

SMR

MR

MR

MR

SXoo64.1

RR

RR

RR

RR

MR

SS

SMR

MS

SMS

SXoo66.4

MR

RR

RR

RR

RS

RMS

SMR

MR

MR

MR

SXoo67.3

MR

RR

MR

MR

MR

MR

RMS

MS

MR

SMR

MS

MR

MS

SXoo68.1

MR

RR

MR

RR

MS

RMR

MS

MS

SMS

MR

MR

MS

SXoo77.2

RMR

MR

MR

RR

MR

RMR

MR

MR

SMS

MR

MR

MS

SXoo78.1

RMR

MR

MR

RMR

MR

MR

MS

MR

MS

SS

MS

MR

SS

Xoo80.3

MR

MR

MR

MR

MR

RMR

RMS

MR

MS

SMS

SS

MS

SXoo81.3

MR

RMR

MR

RMR

MR

MR

MS

MR

MS

SMS

MR

MR

MS

SXoo82.2

MR

MR

RMR

RR

RR

MS

MS

MS

SMR

MR

MS

MS

SXoo112.3

RR

RMR

RR

MR

MR

MR

MR

MR

SMR

RR

MR

SXoo116.3

RR

MR

RR

RR

RMR

MR

MR

MR

MR

RMR

MR

SXoo117.3

MR

RR

RR

RMR

RMR

MR

MS

SMR

MR

MR

MR

SXoo123.6

MR

MR

MR

MR

RR

RR

MR

MS

MS

MR

MR

MS

MR

MS

SXoo14.3

RR

MR

MR

MR

MR

MR

RMR

RR

SR

MR

MS

MS

SXoo32.2

MR

MR

RR

RR

MR

MR

MS

MR

RS

MR

MR

MR

MR

SXoo33.2

MR

MR

MR

MR

RR

MR

MR

MS

MR

MR

SR

MR

MR

MR

SXoo37.2

MR

MR

RMR

MR

RMR

MR

MR

MR

MR

MR

MR

MS

MR

MR

SXoo76.3

RR

MR

RR

RMR

RMR

MR

MR

SMR

MR

MR

MR

SXoo83.2

RMR

RR

RR

MR

RMS

MS

MR

SMR

MR

MR

MR

SXoo85.1

RR

RR

MR

RR

RMR

MR

MR

MR

MR

MR

MR

MR

SXooNIA

B-1

RMR

RMR

RMR

MR

RMR

MR

MR

SMS

MS

MR

MS

SXoo1.0-2010

MR

RR

MR

MR

MR

MR

RMS

SR

SR

RMR

MR

SXoo21.2-10

SMR

MR

MS

MS

MS

MR

MS

SMS

MR

MR

MR

MS

MR

MS

S

(continued)


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Table

4.

(Continued).

Isolates

IRBB

-50

IRBB

-51

IRBB

-52

IRBB

-53

IRBB

-54

IRBB

-55

IRBB

-57

IRBB

-58

IRBB

-59

IRBB

-60

IRBB

-61

IRBB

-62

IRBB

-63

IRBB

-64

IRBB

-65

IRBB

-66

IRBB

-24

Xoo32

SMS

SS

MR

RS

MR

MS

MR

MR

MS

MR

MS

SMS

SXoo33.3

SS

MS

MS

SS

SMS

SMS

SS

SMS

SMS

SXoo43.5

SS

SMS

SS

MS

MR

SS

SS

MS

MS

MS

MS

SXoo55.2

SS

MS

SS

MS

MR

SS

MR

MR

MS

MS

MR

MR

MR

SXoo59.8

MS

SS

SS

MR

SMR

MS

MS

MS

SMS

MR

SMS

SXoo59.13

MS

MR

MS

MS

SS

MS

MS

SMS

SS

MS

MS

MS

MS

SXoo67.7

MR

MS

MS

MS

MR

MS

MR

MR

MS

MR

MS

MS

MR

MR

MS

MR

SXoo67.8

MR

MR

MS

RR

RMR

RMR

RS

MS

MR

MR

SMR

SXoo68.4

RR

MR

MS

RMR

RR

MS

RS

MR

MR

MR

MR

MR

SXoo84.4

MS

MR

MS

SMS

MS

MR

MS

MS

MR

MS

MS

SMS

MS

SS

Xoo86.6

MR

MS

MS

MS

MS

MR

MR

MR

MS

MS

MR

MR

MR

MR

MS

MR

SXoo87.4

MR

SMS

MS

MR

MR

MS

MR

MR

MS

MR

MR

MR

SMS

MS

SXoo87.6

MS

MR

MR

MS

MR

MR

MR

SS

MR

MR

MR

SMS

MR

MR

SXoo88.2

MR

MS

SS

MS

SS

MR

MS

MR

SMS

MS

MR

MR

MR

SXoo88.12

MR

SS

MR

MR

SS

MR

MR

MS

MR

MS

MS

MR

MR

MS

SXoo89.2

MS

SMS

SMR

SS

MS

MR

MS

MS

MR

MR

MS

SMS

SXoo89.7

MR

SS

SS

MS

SR

MS

MS

SMR

MS

SMR

MS

SXoo90.8

MR

MR

MS

MR

MR

MR

MS

MR

MS

MS

MS

MR

MS

MR

MR

MR

SXoo102.8

MS

MS

MS

MS

MR

SMR

MR

MS

MR

MS

SMR

MR

MR

MS

SR

andMR

responses

R¼

20;

MR¼

29

R¼

24;

MR¼

24

R¼

25;

MR¼

19

R¼

20;

MR¼

24

R¼

30;

MR¼

21

R¼

29;

MR¼

19

R¼

14;

MR¼

32

R¼

32;

MR¼

22

R¼

0;

MR¼

20

R¼

4;

MR¼

26

R¼

3;

MR¼

20

R¼

0;

MR¼

12

R¼

3;

MR¼

28

R¼

3;

MR¼

25

R¼

1;

MR¼

30

R¼

0;

MR¼

22

R¼

26;

MR¼

15

R,resistant(5

5cm

lesionlength);MR,moderately

resistant(5–10cm

lesionlength);MS,moderately

susceptible

(10–15cm

lesionlength);S,susceptible

(415cm

lesion

length).R

andMR

responseshavebeenshownwithbold

letters.


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reaction analysis showed that each NILs was susceptible to one or more isolate.None of the single gene performance can be expected to control all the isolates of BB.This is in line with earlier studies in eastern India (Shanti et al. 2001).

Xa21, a dominant gene located on chromosome number 11 in Oryzalongistaminata (Song et al. 1995) perform well singly as well as in combinationagainst many isolates in this study; however, some isolates shows virulence andovercome the Xa21. The same results were documented by Mannan et al. (2009)according to whom Xa21 gene is overcome by only one race PKX 2, a dominant racein Pakistan, of Xoo while effective against other four races. Shanti et al. (2001)reported that Xa21 is effective and stable against multiple isolates of Xoo. Xoostrains virulent to Xa21 had also been reported from Japan (Lin et al. 1996), Korea(Lee et al. 1999), Nepal (Adhikari et al. 1999b), Sri Lanka (Ochiai et al. 2000) andIndia (Goel et al. 1998). Avirulence of most South Asian strains and many Koreanstrains of X. oryzae pv. oryzae on Xa21 implies that avrXa21 is widely distributed inAsian populations of X. oryzae pv. oryzae. However, the virulence of X. oryzae pv.oryzae strains to Xa21 might be the result of a mutation in avrXa21 gene (Lee et al.1999). However, in this study, this gene was ineffective against some isolates of theXoo evaluated. Moreover, Xa21 was found to be ineffective against sevenBangladeshi races of Xoo (Jalaluddin et al. 2005). Ineffectiveness of Xa21 againstsome pathotypes of Xoo as recorded here may be due to the failure of some membersof these small multigenic families to recognise specific pathogen ligands (Song et al.1995) and subsequent activation of an intracellular defence response (Wang et al.1996a). These results suggest that the resistance conferred by Xa21 may not beeffective against all the isolates in a particular location. Thus, in order to maximisethe durability of resistance, it is important to determine the best strategy for thedeployment of lines containing Xa21 in a particular location (Wang et al. 1996b). Itwas also observed that, in this study, Xa21 was contributing the largest componentof resistance not only as a single gene but also in two or three gene combinationwhich may be due to quantitative interaction among R genes in which the resistancelevel of one R gene with strong effect tended to be compensated by another R genethat was moderately resistant or defeated by the isolate tested (Jeung et al. 2006).

The performance of IRBB-13 carrying xa13, a recessive gene located onchromosome number 8, was found effective, and many isolates in Punjab wereavirulent to IRBB-13. xa13 was reported to confer resistance against three racesPKX2, PKX3 and PKX4 in Pakistan (Mannan et al. 2009), PXO99A the broadlyvirulent race in Philippines (Ogawa et al. 1987) and seven Xoo pathoypes in India(Lore et al. 2011). In Vietnam, IRBB-13 was found highly susceptible whenevaluated as a single gene line (Loan et al. 2006) which indicates the prevalence ofxa13 virulent strain in Vietnam Xoo population. Moreover, rice line IRBB-13 alsoreported to be attacked by majority of pathotypes in Sri Lanka (Ochiai et al. 2000).For both xa5 and xa13, resistance is the result of mutation affecting a vital host gene(Chu et al. 2006) which leads to mutation in an essential host protein necessary forbacterial virulence (Fraser 1986, 1990). The performance of IRBB14 carrying Xa14was also good in Punjab, but in another study, it was found to be susceptible to 81%isolates collected throughout the Pakistan ((Mannan et al. 2009) and 100%susceptible to all prevailing races of Xoo in Philippine (Adhikari et al. 1999a),indicating that avirulence of Xa14 is prevalent in Xoo population of Punjab while inPunjab province of India, Xa14 was found to susceptible against all the races of Xoo(Lore et al. 2011). A high frequency of isolates incompatible with NIL containing


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Xa7 was observed in this investigation. Thus, Xa7 as a single gene is also an effectivegene for deployment in BB resistance in Punjab. Xa7 has also been speculated toconfer durable resistance in Korea (Jeung et al. 2006). The rest of Xa genes haveresistant to one or few isolates but most of isolates attained the virulence toovercome the resistance.

Pyramid lines having two or three gene combinations conferred a broaderspectrum of resistance to BB than single R genes, suggesting synergism andcomplementation among R genes (Huang et al. 1997; Adhikari et al. 1999a;Narayanan et al. 2002). A gene pyramiding strategy depends on the reaction oflines carrying multiple genes. It has been found, in this investigation, that theperformance of IRBB-58 (Xa21, Xa4, xa13) was the best in all pyramids. Similarly,combination of two genes, IRBB-54 (Xa21 þ xa5) and IRBB-55 (Xa21 þ xa13),showed high level of resistance. IRBB-54 was also reported in Korea (Jeung et al.2006) and India (Singh et al. 2002) to be effective and conferred strong resistanceagainst Xoo isolates. In addition, the combination of two recessive genes, xa5 andxa13, was also effective showing R and MR behaviour against many isolates in thisstudy. These results agree with similar studies in which it was observed that thecombination of xa5 þ xa13 provided protection against all Xoo isolates tested inPunjab state of India (Goel et al. 1998; Singh et al. 2002). Research on molecularmechanism of disease resistance conferred by plant recessive genes against bacterialpathogens is just beginning. Biochemical, genetic and cell biology studies will beimportant for understanding how xa5 and xa13 lead to resistance (Anjali et al. 2007).In this study, the evaluation of NILs and pyramids lines revealed that pyramid lineIRBB-54 in two genes combination and IRBB-58 in three genes combination conferresistance against maximum isolates while further increase in gene combination, i.e.four and five gene combinations reduce the resistance. These results are in line withan earlier study which concludes that Pyramid line with three gene combinationswould be most promising in Pakistan against BLB (Mannan et al. 2009). IRBB-54was also recommended to be used in breeding program to develop the rice varietieswith wide spectrum disease resistance in Cuulong river delta (Dinh et al. 2010).Yoshimura et al. (1995) reported that plants with two genes gave high level ofresistance to Xoo in Philippine which also support the recommendation of IRBB-54. In another investigation in Punjab state of India, pyramid lines IRBB-53(xa5 þ xa13), IRBB-55(xa13 þ xa21), IRBB-56 (Xa4 þ xa5 þ xa13), IRBB-57(Xa4 þ xa5 þ Xa21), IRBB-58 (Xa4 þ xa13 þ Xa21) and IRBB-59(Xa5 þ xa13 þXa21) were effective against all pathotypes (Singh et al. 2002; Lore et al. 2011).Similarly, in Nepal, three gene combination NH21 (Xa4 þ xa5 þ xa13) and NH24(Xa4 þ xa5þ Xa21) were effective against local Xoo populations. Moreover, IRBB-50, IRBB-54 and IRBB-57 expressed strong resistance in Korea (Jeung et al. 2006).The efficacy of IRBB-58 seems to be similar in both Punjab province of India andPunjab province of Pakistan which may be due to similar climate. The combinationof xa5 and Xa7 into the same line would be more effective than using single R genesin Philippines (Vera-Cruz et al. 2000). Similar combination should also broughtunder consideration which was not evaluated yet in Pakistan although in ourinvestigation, Xa7, as a single gene behave well and showed R and MR againstmaximum isolates. Thus, there is a variation in the effectiveness of single genes indifferent regions of Asia (Adhikari et al. 1999a).

The information gained in this study has significant implications for theresistance gene deployment in Punjab region. Developing sound strategy for


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deployment of R gene containing lines is most challenging and an important areabecause of the ability of pathogens to rapidly overcome major R genes. This studyalso explored the potential of gene pyramiding to develop cultivars with durableresistance to BB disease.

Conclusion

In conclusion, behaviour of different xa genes revealed the existence of diverse Xoopopulation in Punjab province of Pakistan. Although many resistance genes werefound to be useful against the small proportion of pathogen population, none of thegene or gene combination can combat against all the isolates tested in this study.Based on our results, Xa21 and xa13 resistance genes were found to be most effectivefollowed by Xa14 and Xa7 while R gene pyramid of Xa4 þ xa13 þ Xa21 would bethe most effective for improving rice cultivars against BB disease. Xa14 and Xa7could also speculate to have durable resistance as a single gene or in combinationswith Xa21 and Xa13. In this study, only 26 R genes/gene combinations wereevaluated; so, there is a dire need to evaluate new combinations of genes or newlyidentified R genes which can combat against all Xoo isolate not only from Punjabbut throughout the Pakistan. It is also desirable to deploy different resistant genes indifferent location to avoid any epidemic. The information generated could be appliedin breeding programmes to develop rice cultivars with durable resistance against BBpathogen.

Acknowledgements

We acknowledge the financial support provided by the Punjab Agricultural Research Board(PARB) Punjab, Pakistan.

References

Abbasi FM, Masood R, Ahmad H, Khan U, Afzal M, Inamullah, Rehman MU, Khan MT,Akbar K, Khan MA. 2011. Molecular screening of Pakistani rice germplasm for xa5 generesistance to bacterial blight. Afr J Biotechnol. 10:2833–2837.

Adhikari TB, Basnyat RC, Mew TW. 1999a. Virulence of Xanthomonas oryzae pv. oryzae onrice lines containing single resistance genes and gene combinations. Plant Dis. 83:46–50.

Adhikari TB, Mew TW, Leach JE. 1999b. Genotypic and pathotypic diversity in Xanthomonasoryzae pv. oryzae in Nepal. Phytopathology. 89:687–694.

Akhtar MA, Zakaria M, Abbasi FM, Masood MA. 2003. Incidence of bacterial blight of ricein Pakistan during 2002. Pak J Bot. 35(5):993–997.

Anjali S, Pascuzzi L, McCouch R. 2007. Recessive resistance genes and the Oryza sativa–Xanthomonas oryzae pv. oryzae pathosystem. Mol Plant-Microbe Interact. 20(277):731–739.

Chen S, Liu X, Zeng L, Ouyang D, Yang J, Zhu X. 2011. Genetic analysis and molecularmapping of a novel recessive gene xa34(t) for resistance against Xanthomonas oryzae pv.oryzae. Theor Appl Genet. 122:1331–1338.

Chu Z, Yuan M, Yao J, Ge X, Yuan B, Xu C, Li X, Fu B, Li Z, Bennetzen JL, Zhang Q,Wang S. 2006. Promoter mutations of an essential gene for pollen development result indisease resistance in rice. Genes Dev. 20:1250–1255.

Cottyn B, Mew TW. 2004. Bacterial blight of rice. In: Goodman RM, editor. Encyclopedia ofplant and crop science. New York: Marcel Dekker. p. 79–83.

Dinh HD, Du PV, Loan LC. 2010. Study on the use of combination resistance genes in ricelines against Xanthomonas oryzae pv. oryzae in Cuulong river delta. Omonrice. 17:147–151.

Fraser RSS. 1986. Genes for resistance to plant viruses. CRC Crit Rev Plant Sci. 3:257–294.


Dow

nloa

ded

by [

Upp

sala

uni

vers

itets

bibl

iote

k] a

t 10:

20 0

7 O

ctob

er 2

014

Fraser RSS. 1990. The genetics of resistance to plant viruses. Ann Rev Phytopathol. 28:179–200.

Goel RK, Kaur L, Saini RG.1998. Effectiveness of different Xa genes against Xanthomonasoryzae pv. oryzae population causing bacterial blight of rice in Punjab (India). RiceGenetic Newsl. 15:131.

Gomez KA, Gomez AA. 1984. Statistical procedures for agricultural research. 2nd ed. NewYork: John Wiley and Sons.

Huang N, Angeles ER, Domingo J, Magpantay G, Singh S, Zhang G, Kumaravadivel N,Bennett J, Khush GS.1997. Pyramiding of bacterial blight resistance genes in rice: marker-assisted selection using RFLP and PCR. Theor Appl Genet. 95:313–320.

Jalaluddin M, Yamamoto T, Nakai H, Tsuyumu S. 2005. Pathogenic variability and DNAfingerprinting of Xanthomonas oryzae pv. oryzae from Bangladesh. SABRAO J BreedGenet. 37(1):1–10.

Jeung JU, Heu SG, Shin MS, Vera-Cruz CM, Jena KK. 2006. Dynamics of Xanthomonasoryzae pv. oryzae population in Korea and their relationship to known bacterial blightresistance genes. Phytopathology. 96:867–875.

Kauffman HE, Reddy APK, Hsieh SPY, Merca SD. 1973. An improved techniquefor evaluating resistance of rice varieties to Xanthomonas oryzae. Plant Dis Rep.57:537–541.

Khan JA, Arshad HMI, Jamil FF, Hasnain S. 2008. Screening of rice germplasm againstbacterial leaf blight disease. Pak J Phytopathol. 20(1):48–51.

Khan JA, Arshad HMI, Jamil FF, Hasnain S. 2009. Evaluation of rice genotypes againstbacterial leaf blight (BLB) disease. Pak J Phytopathol. 21(1):26–30.

Lee SW, Choi SH, Han SS, Lee DG, Lee BY. 1999. Distribution of Xanthomonas oryzae pv.oryzae strains virulent to Xa21 in Korea. Phytopathology. 89:928–933.

Lin XH, Zhan DP, Xie YF, Gao HP, Zhang Q. 1996. Identifying and mapping a new gene forbacterial blight resistance in rice based on RFLP markers. Phytopathology. 86:1156–1159.

Loan LE, Ngan VTT, Du PV. 2006 . Preliminary evaluation on resistance genes against ricebacterial leaf blight in Can Tho Province – Vietnam. Omonrice. 14:44–47.

Lore JS, Vikal Y, Hunjan MS, Goel RK, Bharaj TS, Raina GL. 2011. Genotypic andpathotypic diversity of Xanthomonas oryzae pv. oryzae, the cause of bacterial blight of ricein Punjab state of India. J Phytopath. 159(7–8):479–487.

Mannan S, Malik SA, Ahamad I, Mirza JI, Akhtar MA. 2009. Studies on virulence reactionsof local isolates of Xanthomonas oryzae pv. Oryzae. Pak J Bot. 41(1):391–402.

Mew TW, Majid A. 1977. Bacterial blight of rice in Pakistan. IRRN. 2(1):5.Narayanan NN, Baisakh N, Vera-Cruz CM, Gnanamanickam SS, Datta K, Datta SK. 2002.

Molecular breeding for the development of blast and bacterial blight resistance in rice cv.IR50. Crop Sci. 42:2072–2079.

Naveed SA, Babar M, Arif A, Zafar Y, Sabar M, Ali I, Chragh M, Arif M. 2010. Detection ofbacterial blight resistant gene xa5 using linked marker approaches. Afr J Biotech.9(24):3549–3554.

Ochiai H, Horino O, Miyajima K, Kaku. 2000. Genetic diversity of Xanthomonas oryae pv.oryzae strains from Sri Lanka. Phytopathology. 90:415–421.

Ogawa T, Lin L, Tabien RE, Khush GS. 1987. A new recessive gene for resistance to bacterialblight of rice. Rice Genetic Newsl. 4:98–100.

Onasanya A, Ekperigin MM, Nwilene FE, Sere Y, Onasanya RO. 2009. Two pathotypes ofXanthomonas oryzae pv. oryzae virulence identified in west Africa. Curr Res Bacteriol.2(2):22–35.

Salim M, Akram M, Akhtar MA, Ashraf M. 2003. Rice: a production hand book. Islamabad:Pakistan Agricultural Research Council. 70 p.

Sanchez AC, Brar DS, Huang N, Li Z, Khush GS. 2000. Sequence tagged site marker-assistedselection for three bacterial blight resistance genes in rice. Crop Sci. 40:792–797.

Shanti ML, George MLC, Vera-Cruz CM, Bernando M, Nelson RJ, Leung H, Reddy JN,Sridhar R. 2001. Identification of resistance genes effective against rice bacterial blightpathogen. Plant Dis. 85:506–512.

Singh S, Sidhu JS, Huang N, Vikal Y, Li Z, Brar DS, Dhaliwal HS, Khush GS. 2001.Pyramiding three bacterial blight resistance genes (xa5, xa13 and Xa21) using marker-assisted selection into indica rice cultivar PR106. Theor Appl Genet. 102:1011–1015.


Dow

nloa

ded

by [

Upp

sala

uni

vers

itets

bibl

iote

k] a

t 10:

20 0

7 O

ctob

er 2

014

Singh S, Sodhi M, Vikal Y, George MLC, Bala GS, Mangat GS, Garg M, Sidhu JS, DhaliwalHS. 2002. DNA fingerprinting and virulence analysis of Xanthomonas oryzae pv. oryzaeisolates from Punjab, northern India. Euphytica. 130:107–115.

Song WY, Wang GL, Chen L, Kim KS, Holsten T, Wang B, Thai Z, Thu LH, Fauquet C,Ronald PC. 1995. The rice disease resistance gene Xa-21 encoded a receptor kinase-likeprotein. Science. 270:1804–1806.

Suparyono, Sudir, Suprihanto. 2004. Pathotype profile of Xanthomonas oryzae pv. oryzaeisolates from the rice ecosystem in Java. Indones J Agri Sci. 5(2):63–69.

Swings J, Mooter VD, Vauterin L, Hoste B, Gills M, Mew TW, Kersters K. 1990.Reclassification of the causal agents of bacterial blight (Xanthomonas compestris pv.oryzae) and bacterial leaf streak (Xanthomonas compestris pv. oryzocola) of rice aspathovars of Xanthomonas oryzae (ex Ishiyama 1922) sp. Nov., nom. rev. Int J Syst EvolMicorbiol. 40:309–311.

Vera-Cruz CM, Bai J, Ona I, Leung H, Nelson RJ, Mew TW, Leach JE. 2000. Predictingdurability of a disease resistance gene based on an assessment of the fitness loss andepidemiological consequences of avirulence gene mutation. Proc Natl Acad Sci USA.97:13500–13505.

Wang GL, Song WY, Ruan DL, Sideris S, Ronald PC. 1996a. The cloned gene, Xa21, confersresistance to multiple Xanthomonas oryzae pv. oryzae isolates in transgenic plants. MolPlant-Microbe Interact. 9(9):850–855.

Wang OL, Song WY, Chen LL, Ruan R, Sidesis S, Ronald PC. 1996b. Resistance spectrum,race specificity and expression of the Xa21 gene family. IRRN. 21(2–3):45–46.

Wang YS, Pi LY, Chen X, Chakrabarty PK, Jiang J. 2006. The ubiquitin ligase XB3 interactswith the rice receptor- like kinase Xa21 and is required for Xa-21 mediated diseaseresistance. Plant Cell. 18:3635–3646.

Yamamoto T, Hifni HR, Muchmud M, Nishizawa T, Tantera DM. 1977. Variation inpathogenicity of Xanthomonas oryzae pv. oryzae (Uyeda et Ishiyama) Dowson andresistance of rice varieties to the pathogen. Contr Centr Res Ins Agric Bogo. 28:22.

Yoshimura S, Yoshimura A, Twata I, Mccouch SR, Abenes MI, Baraoidan MR, Mew TW,Nelson RJ. 1995. Tagging and combining bacterial blight resistance genes in rice usingRAPD and RFLP markers. Mol Breed. 1:375–387.


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evaluation of resistance genes in rice against local isolates of xanthomonas oryzae pv. oryzae in...

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