Introgression of bacterial leaf blight (BLB) resistant gene, Xa7 into MARDI elite variety, MR219 by marker assisted backcrossing (MABC) approach

Abstract Bacterial leaf blight (BLB) is one of the major rice diseases in Malaysia. This disease causes substantial yield loss as high as 70%. Development of rice varieties which inherited BLB resistant traits is a crucial approach to promote and sustain rice industry in Malaysia. Hence, this study aims were to enhance BLB disease resistant characters of high yielding commercial variety MR219 through backcross breeding approach with supporting tool of marker-assisted selection (MAS). Broad spectrum BLB resistance gene, Xa7 from donor parent IRBB7 were introgressed into the susceptible MR219 (recurrent parent) using two flanking markers ID7 and ID15. At BC3F4, we managed to generate 19 introgressed lines with homozygous Xa7 gene and showed resistant characteristics as donor parent when it was challenged with Xanthomonas oryzae pv. oryzae through artificial inoculation. Recurrent parent MR219 and control variety, MR263 were found to be severely infected by the disease. The improved lines exhibited similar morphological and yield performance characters as to the elite variety, MR219. Two lines, PB-2-107 and PB-2-34 were chosen to be potential lines because of their outstanding performances compared to parent, MR219. This study demonstrates a success story of MAS application in development of improved disease resistance lines of rice against BLB disease.

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Evaluation of Xa7 Introgressed Lines Against Bacterial Leaf Blight (BLB) Disease and Their Agronomic Performances

10.21203/rs.3.rs-113691/v1 ◽

2020 ◽

Author(s):

Siti Norhidaya Yazid ◽

Mohd Bahagia Ab Ghaffar ◽

Shahril Ab Razak ◽

Zuraida Abd Rahman ◽

Kogeethavani Ramachandran ◽

...

Keyword(s):

Yield Loss ◽

Leaf Blight ◽

Xanthomonas Oryzae ◽

Bacterial Leaf Blight ◽

Recurrent Parent ◽

Commercial Variety ◽

Potential Yield ◽

Rice Varieties ◽

Donor Parent ◽

Resistant Trait

Abstract Bacterial leaf blight (BLB) is one of the major rice diseases in Malaysia. The disease can potentially cause a 30 to 50% yield loss to the rice crop. Hence, the utilization of resistant rice varieties to BLB is a crucial approach to prevent potential yield loss and to ensure the sustainability of the rice industry in Malaysia. This study aims to incorporate BLB resistant trait into a susceptible, high yielding, popular commercial variety MR219. The identified donor parent is IRBB7, harboring Xa7, a broad-spectrum BLB resistant gene which closely linked to two STS markers, the ID7 and ID15. Backcrossing was initiated, using IRBB7 as the donor and MR219 as the recurrent parents. Marker-assisted selection (MAS) was applied to monitor and confirm the introgression of Xa7 in the progenies of the cross based on alleles produced by the markers. We managed to generate 19 BC3F4 lines harboring homozygous Xa7 gene that were phenotypically resistant when challenged with Xanthomonas oryzae pv. oryzae through an artificial inoculation. The improved lines exhibited similar morphological and yield performance of the recurrent parent. Two lines, PB-2-107 and PB-2-34 were identified for their outstanding performances which are comparable to MR219. This study demonstrates the advantage of MAS application in the improvement of disease resistance traits in the elite rice cultivars.

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PEMANFAATAN PIRAMIDA GEN KETAHANAN TERHADAP PENYAKIT HAWAR DAUN BAKTERI DALAM MENDUKUNG PERAKITAN VARIETAS UNGGUL PADI Application of Gene Pyramiding For Resistance to Bacterial Leaf Blight to Develop New Rice Variety

Jurnal Penelitian dan Pengembangan Pertanian ◽

10.21082/jp3.v39n1.2020.p11-20 ◽

2020 ◽

Vol 39 (1) ◽

pp. 11

Author(s):

Fatimah Fatimah ◽

Joko Prasetiyono

Keyword(s):

Molecular Marker ◽

Rice Variety ◽

Gene Pyramiding ◽

Leaf Blight ◽

Rice Production ◽

Xanthomonas Oryzae ◽

Bacterial Leaf Blight ◽

Yield Potential ◽

Rice Varieties ◽

Marker Assisted Backcrossing

Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv oryzae (Xoo) is an important bacterial disease and very destructive to rice plant. BLB decreased rice production from 20%-30% up to 80%. Host-plant resistance is a cost-effective and environmentally safe approach to reduce yield loss. However the development of new rice variety by conventional selection would take several years. The genetic improvement in rice production considered as a vital program in order to ensure national food security. The availability of corresponding molecular marker makes it more precision and efficient by reducing the time required for selection. This present article highlights the molecular approach in breeding for BLB disease resistant rice varieties. In detail, it will be discussed the application of molecular marker assisted backcrossing and pyramiding gene resistance offered breeders to accelerate the rice breeding program for resistance to BLB. The pyramiding of three resistance BLB genes (xa5, Xa7, and Xa21and one gene (Xa4) as a background into two elite indica rice varieties, Ciherang and Inpari 13, was introduced successfully. The combining of conventional breeding, marker assisted backcrossing, disease evaluation, agronomic performance and yield has led the significant resistance of pyramid lines to Xoo Race III, IV and VIII in vegetative and generative phase while their yield potential was maintained (6-7 ton/ha). The current status of Ciherang-HDB and Inpari 13-HDB pyramid lines is the production of nucleoseeds and breeder seeds. This broad spectrum and durable resistance characteristic may help in controlling BLB disease in different region of Indonesia and it will facilitate the rice self-sustainability program.Keywords: Rice, gene pyramiding, plant breeding, molecular marker. AbstrakPenyakit hawar daun bakteri (HDB) yang disebabkan oleh Xanthomonas oryzae pv oryzae (Xoo) merupakan penyakit penting pada tanaman padi karena dapat menurunkan produksi padi rata-rata 20-30% bahkan dapat mencapai 80%. Penggunaan varietas tahan merupakan cara pengendalian yang paling efektif, ramah lingkungan, dan mudah dilakukan. Namun pengembangan varietas unggul baru melalui seleksi konvensional memerlukan waktu lebih lama. Perbaikan varietas padi perlu terus dikembangkan dalam mendukung ketahanan pangan dan kemandirian pangan nasional. Tersedianya marka molekuler membantu proses pemuliaan tanaman menjadi lebih presisi dan lebih efisien sehingga mengurangi waktu seleksi pada tanaman progeni. Tulisan ini memfokuskan pendekatan molekuler dalam pemuliaan varietas tahan penyakit HDB melalui piramida gen ketahanan untuk mempercepat progam pemuliaan padi tahan penyakit HDB. Kegiatan menggabungkan tiga gen ketahanan (xa5, Xa7, dan Xa21) dan satu gen (Xa4) sebagai background ke dalam padi varietas Ciherang dan Inpari-13 telah berhasil dilakukan. Melalui penggabungan beberapa pendekatan yaitu pemuliaan konvensional dan silang balik berbantu marka, evaluasi penyakit dan keragaan agronomi serta komponen hasil telah menunjukkan peningkatan ketahanan yang nyata pada galur-galur piramida Ciherang HDB dan Inpari-13 HDB pada tiga ras Xoo (Ras III, IV, dan VIII), baik pada fase vegetatif maupun generatif dengan potensi hasil tidak berbeda nyata dengan tetuanya (6-7 t/ha). Saat ini sudah diproduksi benih inti (NS) dan benih penjenis (BS) galur-galur piramida Ciherang HDB dan Inpari-13 HDB. Dengan demikian, galur-galur piramida memiliki spektrum yang luas dan mampu bertahan dalam jangka waktu lama sehingga dapat mengontrol penyakit HDB di berbagai wilayah Indonesia dan mendukung target pemerintah untuk mempertahankan swasembada beras secara berkelanjutan.Kata kunci: Padi, piramida gen, pemuliaan tanaman, marka molekuler.

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Field Evaluation Of Conde Progenies With Early Heading Date And Resistance To Bacterial Leaf Blight

ANNALES BOGORIENSES ◽

10.14203/ann.bogor.2019.v23.n2.87-96 ◽

2020 ◽

Vol 23 (2) ◽

pp. 87

Author(s):

Fatimah Fatimah ◽

Joko Prasetiyono ◽

Ahmad Dadang ◽

Tasliah Tasliah ◽

Masumah Masumah

Keyword(s):

Agronomic Traits ◽

Rice Variety ◽

Heading Date ◽

Field Evaluation ◽

Leaf Blight ◽

Bacterial Leaf Blight ◽

Early Maturity ◽

South Sulawesi ◽

Donor Parent ◽

Marker Assisted Backcrossing

Heading date is one of key traits in rice adaptation to different environments. Rice with early maturity is very useful for increasing rice production extensively especially in Indonesia. The improvement of rice variety Conde for heading date and resistance to bacterial leaf blight (BLB) was developed through Marker Assisted Backcrossing approach (MAB). Xa7 derived from Conde as recipient parents for resistance to BLB and Hd2 gene derived from Nipponbare as a donor parent for heading date. The aim of this research was to evaluate the performance of heading date and agronomic traits of 85 BC2F4 lines in two field stations, Sukamandi (West Java) and Maros (South Sulawesi). Molecular analysis of Xa7 on chromosome 6 and Hd2 gene on chromosome 7 and agronomic performance was evaluated. Foreground analysis resulted 41% for Xa7 and 66.7% for Hd2 gene in homozygous condition. The majority of lines have similar heading date and yield with Conde and more resistance to bacterial leaf blight (BLB) than Conde. Six lines flowered earlier 5 days than Conde in Sukamandi and three lines flowered earlier 3 days in Maros. Twelve lines with flowered earlier than Conde, resistance to BLB and similar yield with Conde were selected for background analysis resulted 93% genome recovery. These lines would be further evaluated in preliminary yield trail for their stability.

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Recovery of Recurrent Parent Genome in a Marker-Assisted Backcrossing Against Rice Blast and Blight Infections Using Functional Markers and SSRs

Plants ◽

10.3390/plants9111411 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1411

Author(s):

Samuel Chibuike Chukwu ◽

Mohd Y. Rafii ◽

Shairul Izan Ramlee ◽

Siti Izera Ismail ◽

Yusuff Oladosu ◽

...

Keyword(s):

Resistance Genes ◽

Blast Resistance ◽

Leaf Blight ◽

Bacterial Leaf Blight ◽

Functional Markers ◽

Recurrent Parent ◽

Selected Lines ◽

Recurrent Parent Genome ◽

Backcross Breeding ◽

Marker Assisted Backcross Breeding

The most vital aspect of marker-assisted backcross breeding is the recurrent parent genome recovery. This enables the selection of only parents with recovered recipient/recurrent parent genome in addition to the targeted genes. The recurrent parent genome recovery (RPGR) ensures that non-desirable genomic segments are removed while the gene of interest is sustained in the recombined progenies without further segregations. This work was aimed at quantifying the RPGR of backcross populations with introgression of bacterial leaf blight resistance genes. Putra-1, a Malaysian elite variety, high yielding with inherent resistance to blast but susceptible to bacterial leaf blight (BLB), was crossed with IRBB60 which is resistant to BLB disease. The IRBB60 has four Xoo resistance genes—Xa4, xa5, xa13 and Xa21. Tightly linked polymorphic functional and SSR markers were used for foreground selection at every stage of backcrossing to select progenies with introgressed target genes. Background selection was done to quantify the percentage of RPGR in the selected lines using 79 confirmed polymorphic microsatellites. Result obtained showed that the percentage of RPGR was 80.11% at BC1F1, 95.30% at BC2F1 and 95.9% at BC2F2. The introgression of Xa4, xa5, xa13 and Xa21 Xoo resistance genes were faster through the adopted marker-assisted backcross breeding compared to what could be obtained through conventional breeding. All the 16 selected lines displayed resistance to BLB with three lines showing high resistance to the disease. The blast resistance contained in the genetic background of Putra-1 was also sustained in all the selected lines. The newly developed lines were recommended as new rice varieties for commercial cultivation.

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GENETIC VARIABILITIES OF AGRONOMIC TRAITS AND BACTERIAL LEAF BLIGHT RESISTANCE OF HIGH YIELDING RICE VARIETIES

Indonesian Journal of Agricultural Science ◽

10.21082/ijas.v20n2.2019.p43-54 ◽

2020 ◽

Vol 20 (2) ◽

pp. 43

Author(s):

Nafisah Nafisah ◽

Celvia Roza ◽

Nani Yunani ◽

Aris Hairmansis ◽

Tita Rostiati ◽

...

Keyword(s):

Agronomic Traits ◽

Genetic Resistance ◽

Leaf Blight ◽

Bacterial Leaf Blight ◽

Yield Potential ◽

Blight Resistance ◽

Wet Season ◽

Rice Varieties ◽

Superior Genotypes ◽

Productive Tiller

Hundred of high yielding and bacterial leaf blight (Xanthomonas oryzae pv. oryzae, Xoo) resistant rice varieties released since the 1960s are important sources of genetic materials for exploring superior genotypes. The study aimed to evaluate the genetic resistance of 177 rice varieties to Xoo and their agronomic traits. The evaluations were conducted at the Indonesian Center for Rice Research Experimental Station during the wet season (December 2015-March 2016). The bacterial leaf blight resistance was evaluated for Xoo pathotypes III, IV, and VIII using the clipping method. The genetic variation among genotypes was categorized as low (0–10%), medium (10–20%), and high (>20%), whereas the heritability was categorized as low (0-30%), medium (30-60%), and high (>60%). The variability of resistance to Xoo pathotypes, grain yield, and spikelet fertility was low, while the variability of plant height, productive tiller number, filled grain, and total spikelet was medium, and the variability of unfilled grain number was high. The 29 varieties were categorized as superior based on their agronomic traits or resistance to Xoo pathotypes. In conclusion, Batutegi and Fatmawati were superior in the total spikelet number, while Rojolele and Inpari 2 were supreme in the thousand-grain weight. Dodokan had a very short maturity, and Inpari 24, Conde, Kalimas, Angke, Inpari 17, and Inpara 8 had the highest resistance to Xoo pathotypes. The study implies that the identified rice superior genotypes could be used as genetic materials to design cross combinations for higher yield potential and BLB resistance varietal improvement.

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Improved bacterial leaf blight disease resistance in the major elite Vietnamese rice cultivar TBR225 via editing of the OsSWEET14 promoter

PLoS ONE ◽

10.1371/journal.pone.0255470 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0255470

Author(s):

Phuong Nguyen Duy ◽

Dai Tran Lan ◽

Hang Pham Thu ◽

Huong Phung Thi Thu ◽

Ha Nguyen Thanh ◽

...

Keyword(s):

Agronomic Traits ◽

Rice Variety ◽

Rice Cultivar ◽

Leaf Blight ◽

Bacterial Leaf Blight ◽

Transcription Activator ◽

Rice Varieties ◽

Sugar Transporters ◽

Blight Disease ◽

Mutant Lines

TBR225 is one of the most popular commercial rice varieties in Northern Vietnam. However, this variety is highly susceptible to bacterial leaf blight (BLB), a disease caused by Xanthomonas oryzae pv. oryzae (Xoo) which can lead to important yield losses. OsSWEET14 belongs to the SWEET gene family that encodes sugar transporters. Together with other Clade III members, it behaves as a susceptibility (S) gene whose induction by Asian Xoo Transcription-Activator-Like Effectors (TALEs) is absolutely necessary for disease. In this study, we sought to introduce BLB resistance in the TBR225 elite variety. First, two Vietnamese Xoo strains were shown to up-regulate OsSWEET14 upon TBR225 infection. To investigate if this induction is connected with disease susceptibility, nine TBR225 mutant lines with mutations in the AvrXa7, PthXo3 or TalF TALEs DNA target sequences of the OsSWEET14 promoter were obtained using the CRISPR/Cas9 editing system. Genotyping analysis of T0 and T1 individuals showed that mutations were stably inherited. None of the examined agronomic traits of three transgene-free T2 edited lines were significantly different from those of wild-type TBR225. Importantly, one of these T2 lines, harboring the largest homozygous 6-bp deletion, displayed decreased OsSWEET14 expression as well as a significantly reduced susceptibility to a Vietnamese Xoo strains and complete resistance to another one. Our findings indicate that CRISPR/Cas9 editing conferred an improved BLB resistance to a Vietnamese commercial elite rice variety.

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Metode Penyimpanan Bakteri Xanthomonas Oryzae pv. oryzae Penyebab Penyakit Hawar Daun Bakteri Pada Tanaman Padi Menggunakan Glycerol

Jurnal Pengelolaan Laboratorium Pendidikan ◽

10.14710/jplp.2.1.1-7 ◽

2020 ◽

Vol 2 (1) ◽

pp. 1-7

Author(s):

Santi Sariasih ◽

Fitri Widiantini ◽

Wiwin Widiawati

Keyword(s):

Leaf Blight ◽

Xanthomonas Oryzae ◽

Bacterial Leaf Blight ◽

Control Group ◽

Glycerol Solution ◽

Glycerol Concentration ◽

Research Activities ◽

Randomized Design ◽

And Control

The existence of Xanthomonas oryzae pv. oryzae, the bacteria which causes Bacterial Leaf Blight of rice, is really necessary for the laboratory to support the research activities of the phytopathology experts. Long-term preservation by using glycerol under -20°C can be conducted to preserve the culture’s availability to stay viable in the laboratory. This research aimed to determine the glycerol concentration that is able to preserve the viability and pathogenicity of Xanthomonas oryzae pv. oryzae bacteria after being preserved for 3 and 6 months. This experiments were performed using Completely Randomized Design which comprised of six treatments and four replications, they were: glycerol 50%, 40%, 30%, 20%, 10%, and control (without glycerol). The results of this study showed that viability of Xanthomonas oryzae pv. oryzae that was preserved within 20% glycerol solution for 6 months was different compared to control group. The number of Xanthomonas oryzae pv. oryzae bacteria on 20% glycerol was 4,49 x 109 CFU/ml, while on control group was 1,76 x 109 CFU/ml. 20% glycerol concentration had significant effect on the Bacterial Leaf Blight symptoms’ length after 6-months preservation that observed on the 7th day after incubation. The Bacterial Leaf Blight symptoms’ length on 20% glycerol treatment group was 46,2 mm and 22,7 mm on control group. Meanwhile for the 3 months preservation, the administration of glycerol did not show any significant effect on the Xanthomonas oryzae pv. oryzae’s viability and the Bacterial Leaf Blight symptoms’ length.

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Epidemiology and Control of Bacterial Leaf Blight of Corn

Phytopathology ◽

10.1094/phyto-67-1113 ◽

1977 ◽

Vol 77 (9) ◽

pp. 1113 ◽

Cited By ~ 12

Author(s):

Donald R. Sumner

Keyword(s):

Leaf Blight ◽

Bacterial Leaf Blight ◽

And Control

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Seleksi Lapang Ketahanan Beberapa Varietas Padi terhadap Infeksi Hawar Daun Bakteri Strain IV dan VIII

Buletin Plasma Nutfah ◽

10.21082/blpn.v17n2.2011.p80-87 ◽

2016 ◽

Vol 17 (2) ◽

pp. 80 ◽

Cited By ~ 2

Author(s):

Lina Herlina ◽

Tiur S. Silitonga

Keyword(s):

Oryza Sativa ◽

Block Design ◽

Leaf Blight ◽

Xanthomonas Oryzae ◽

Bacterial Leaf Blight ◽

Bacterial Cells ◽

Bacterial Strains ◽

Rice Varieties ◽

Resistance Reaction ◽

Index Of Severity

Field Selection on Several Rice Varieties for Resistance to Bacterial Leaf Blight strain IV and VIII. Bacterial leaf blight (BLB) on rice (Oryza sativa) caused by Xanthomonas oryzae pv. oryzae (Xoo) is the major obstruction for rice production. Powerful strategy to control BLB is generally conducted by planting resistant plant. Meanwhile, the main way to explore germplasm as the source of resistance gene is conducted by selection a wide rice varieties. Field selection for resistance to BLB on 150 rice-varieties (BB-Biogen collection) was conducted in 2009 in Cianjur. Three leaves and flag leaves of individual hills at vegetative and flowering stage were inoculated by clipping the leaf tip with scissors which had been connected with a suspension bottle of bacterial cells (109- 1010 cells/ml) of the isolates which represented bacterial groups (strain) IV and VIII, respectively. Each plant was inoculated with one race. Two weeks after inoculation, length of the lesion developed on the inoculated leaf was measured, as an index of severity of infection by BLB. This experiment was treated as Factorial-Randomized Completed Block Design (two factor-with 3 replications, respectively). The resistancyreaction to strain IV and VIII was observed as the variable tested, while the factors measured consists of plant-varieties and two bacterial strains. The results showed that 11 varieties with a resistance-reaction to Xoo strain IV, inwhich 5 varieties poses a consistent resistance-reaction, i.e: Pulu Bolong, Pelopor, Gombal, Barito and Kapuas. While resistancereaction to Xoo strain VIII obtained only one variety : IR42 (score-1), while 17 others showed intermediate resistancy (score-3). AbstrakPenyakit hawar daun bakteri (HDB) yang disebabkan oleh Xanthomonas oryzae pv. oryzae (Xoo) pada padi (Oryza sativa) merupakan faktor pembatas upaya peningkatan produksi padi. Pencarian gen-gen tahan terhadap HDB sangat diperlukan untuk pengendalian penyakit tersebut. Seleksi ketahanan terhadap HDB dilakukan di Cianjur pada MT 2009 terhadap 150 varietas padi koleksi Bank Gen, BB-Biogen. Isolat Xoo yang diuji adalah strain IV dan VIII. Inokulasi dilakukan dua kali, yaitu pada fase vegetatif dan generatif dengan cara menggunting 3-5 cm dari ujung daun dan daun bendera dengan gunting yang telah dihubungkan dengan botol berisi suspensi Xoo strain IV dan VIII (109-1010 sel/ml). Rancangan percobaan yang digunakan dalam penelitian ini adalah acak kelompok faktorial dengan tiga ulangan. Sebagai varietas pembanding tahan digunakan IRBB7 dan pembanding rentan varietas Kencana Bali. Reaksi ketahanan tertinggi terhadap Xoo strain IV ditunjukkan oleh 11 varietas terpilih dengan reaksi agak tahan, lima varietas di antaranya menunjukkan reaksi yang konsisten agak tahan, yaitu varietas Pulu Bolong, Pelopor, Gombal, Barito, dan Kapuas. Reaksi &lsquo;tahan&rsquo; terhadap Xoo strain VIII ditunjukkan oleh satu varietas introduksi IR42. Untuk varietas terpilih dengan reaksi &lsquo;agak tahan&rsquo; terdapat 17 varietas.

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