026 Genetic Analysis and Breeding for Resistance to Bacterial Wilt in Capsicum Pepper

Bacterial wilt caused by Ralstonia solanacearum is sporadically causing damage to pepper in Korea. We put efforts in analyzing the genetics of resistance to bacterial wilt and in subsequent breeding for resistance by selection. Two Korean cultivars, Subi and Chilsung, were crossed with a resistant source, MC-4, which was kindly provided by Lopes in Brazil. In addition, four breeding lines bred for resistance to Phytophthora blight were crossed with another resistance source, PBC631, which we received from AVRDC. F2 and backcross populations of the crosses were developed and tested by inoculation by dipping the roots of the seedlings before transplanting 25 days after seeding. Segregation in the F2 and backcross populations did not fit any mode of simple Mendelian inheritance, but appeared inheriting in a quantitative mode with relatively low heritability. Selection was practiced in the subsequent F3, BC1F2, F4, and BC1F3 generations and a few resistant selections were obtained.

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Selection and Inheritance of Tomato Resistance against Ralstonia solanacearum

Jurnal Perlindungan Tanaman Indonesia ◽

10.22146/jpti.35464 ◽

2019 ◽

Vol 23 (1) ◽

pp. 61

Author(s):

Isna Maulida ◽

Rudi Hari Murti ◽

Triwidodo Arwiyanto

Keyword(s):

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Dominant Gene ◽

Tomato Plants ◽

Breeding Lines ◽

Back Cross ◽

Inheritance Patterns ◽

Randomized Design ◽

Resistant Varieties ◽

Resistant Lines

Ralstonia solanacearum is a plant pathogen causes wilting which is a major obstacle in the cultivation of tomato plants. In plant breeding, knowledge of the source of resistance genes and inheritance patterns is important in the development of bacterial wilt resistant varieties. This study aimed to obtain bacterial wilt resistant lines and to find out the inheritance pattern of tomato resistance to bacterial wilt. Selection of resistant plant involved the selected breeding lines from irradiation and crossing collections of the Genetic Laboratory, Faculty of Agriculture, Universitas Gadjah Mada. Introduced lines of H-7996 and F1 Permata and Timoti were used as a control. H-7996 as resistant parents and GM2 as susceptible parents, and their offspring include F1 GM2 x H-7996, F1 reciprocal, F2, Back Cross 1 (F1 x GM2), and Back Cross 2 (F1 x H-7996) used in testing inheritance patterns. Inoculation was carried out 1 week after planting by pouring 100 ml of water suspension of R. solanacarum (108 cfu/ml) on the roots. Completely Randomized Design (CRD) was used in this experiment. The scoring observation was carried out every week for one month. This study showed that Permata as a control was the most resistant, while Timoti and H-7996 were medium resistant. The CLN, G6, G8, and G7 lines were susceptible medium, yet only G8 and G7 with the smallest percentage of disease intensity and not significantly different than Timoti. The resistance gene to bacterial wilt on H-7996 was controlled by genes in the cell nucleus with additive-dominant gene action. Resistance to bacteria has a moderate level of heritability.

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HIGH LEVEL OF RESISTANCE TO BACTERIAL WILT (RALSTONIA SOLANACEARUM) OBTAINED IN LARGE-FRUITED TOMATO BREEDING LINES DERIVED FROM HAWAII 7997

Acta Horticulturae ◽

10.17660/actahortic.2009.808.41 ◽

2009 ◽

pp. 269-274 ◽

Cited By ~ 3

Author(s):

J.W. Scott ◽

G.E. Vallad ◽

J.B. Jones

Keyword(s):

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Breeding Lines ◽

Tomato Breeding ◽

High Level

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Tomato Root Transformation Followed by Inoculation with Ralstonia Solanacearum for Straightforward Genetic Analysis of Bacterial Wilt Disease

Journal of Visualized Experiments ◽

10.3791/60302 ◽

2020 ◽

Cited By ~ 3

Author(s):

Rafael J. L. Morcillo ◽

Achen Zhao ◽

María I. Tamayo-Navarrete ◽

José M. García-Garrido ◽

Alberto P. Macho

Keyword(s):

Genetic Analysis ◽

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Wilt Disease ◽

Tomato Root ◽

Bacterial Wilt Disease ◽

Root Transformation

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Molecular Detection of Ralstonia solanacearum to Facilitate Breeding for Resistance to Bacterial Wilt in Potato

10.1007/978-1-0716-1609-3_18 ◽

2021 ◽

pp. 375-385

Author(s):

Virginia Ferreira ◽

Matías González ◽

María Julia Pianzzola ◽

Núria S. Coll ◽

María Inés Siri ◽

...

Keyword(s):

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Molecular Detection ◽

Breeding For Resistance

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Tomato root transformation followed by inoculation with Ralstonia solanacearum for straightforward genetic analysis of bacterial wilt disease

10.1101/646158 ◽

2019 ◽

Author(s):

Rafael J. L. Morcillo ◽

Achen Zhao ◽

María I. Tamayo-Navarrete ◽

José M. García-Garrido ◽

Alberto P. Macho

Keyword(s):

Genetic Analysis ◽

Pseudomonas Syringae ◽

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Wilt Disease ◽

Tomato Root ◽

Sustainable Solutions ◽

Bacterial Wilt Disease ◽

Tomato Roots ◽

Root Transformation

ABSTRACTRalstonia solanacearum is a devastating soil borne vascular pathogen that is able to infect a large range of plant species, causing an important threat to agriculture. However, the Ralstonia model is considerably under-explored in comparison to other models involving bacterial plant pathogens, such as Pseudomonas syringae in Arabidopsis. Research targeted to understanding the interaction between Ralstonia and crop plants is essential to develop sustainable solutions to fight against bacterial wilt disease, but is currently hindered by the lack of straightforward experimental assays to characterize the different components of the interaction in native host plants. In this scenario, we have developed an easy method to perform genetic analysis of Ralstonia infection of tomato, a natural host of Ralstonia. This method is based on Agrobacterium rhizogenes-mediated transformation of tomato roots, followed by Ralstonia soil-drenching inoculation of the resulting plants, containing transformed roots expressing the construct of interest. The versatility of the root transformation assay allows performing either gene overexpression or gene silencing mediated by RNAi. As a proof of concept, we used this method to show that RNAi-mediated silencing of SlCESA6 of tomato roots conferred resistance to Ralstonia. Here, we describe this method in detail, enabling genetic approaches to understand bacterial wilt disease in a relative short time and with small requirements of equipment and plant growth space.SUMMARYA versatile method for tomato root transformation followed by inoculation with Ralstonia solanacearum to perform straightforward genetic analysis for the study of bacterial wilt disease.

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Genetic Analysis of Growth and Susceptibility to Bacterial Wilt (Ralstonia solanacearum) in Eucalyptus by Interspecific Factorial Crossing

Silvae Genetica ◽

10.1515/sg-2004-0047 ◽

2004 ◽

Vol 53 (1-6) ◽

pp. 254-258 ◽

Cited By ~ 8

Author(s):

S. Gan ◽

M. Li ◽

F. Li ◽

K. Wu ◽

J. Wu ◽

...

Keyword(s):

Genetic Analysis ◽

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Growth Traits ◽

Genetic Correlations ◽

Narrow Sense Heritability ◽

Male And Female ◽

Field Assessment ◽

Dominant Female ◽

Factorial Mating

Summary Factorial mating crosses of Eucalyptus urophylla × E. tereticornis (3 x 5), E. urophylla × E. camaldulensis (3 x 3) and E. urophylla × E. exserta (3 x 3) were used for genetic analysis of growth traits and susceptibility to bacterial wilt (Ralstonia solanacearum). Genetic effects including female, male and female × male interaction were examined for height (H) and diameter at breast height (DBH) at age five as well as final bacterial wilt index (BWI) in both nursery inoculation and field assessment by five years of age. Female, male and female x male variances appeared to have a significant role in growth traits H and DBH though their magnitude varied for the factorials studied. For the trait BWI additive (male) and dominant (female x male) effects were both involved in the genetics of bacterial wilt susceptibility, and additive was the major. Estimates of narrow-sense heritability (h2) for H, DBH and BWI ranged from 0.11 ± 0.06 to 0.70 ± 0.09, varying with either trait or factorial. Growth traits (H and DBH) had low and non-significant phenotypic and genetic correlations with BWI in all the three factorials, ranging from -0.10 ± 0.08 to 0.17 ± 0.14 in coefficient of correlation. This indicates that it may be possible to select superior trees with both fast growth and high resistance to bacterial wilt in eucalypt hybrid populations in operational breeding programs.

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Ralstonia solanacearum Needs Motility for Invasive Virulence on Tomato

Journal of Bacteriology ◽

10.1128/jb.183.12.3597-3605.2001 ◽

2001 ◽

Vol 183 (12) ◽

pp. 3597-3605 ◽

Cited By ~ 201

Author(s):

Julie Tans-Kersten ◽

Huayu Huang ◽

Caitilyn Allen

Keyword(s):

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Soft Agar ◽

Cell Protein ◽

In Planta ◽

Tomato Plants ◽

Bacterial Wilt Disease ◽

Virulence Assay ◽

Flagellar Filament

ABSTRACT Ralstonia solanacearum, a widely distributed and economically important plant pathogen, invades the roots of diverse plant hosts from the soil and aggressively colonizes the xylem vessels, causing a lethal wilting known as bacterial wilt disease. By examining bacteria from the xylem vessels of infected plants, we found thatR. solanacearum is essentially nonmotile in planta, although it can be highly motile in culture. To determine the role of pathogen motility in this disease, we cloned, characterized, and mutated two genes in the R. solanacearum flagellar biosynthetic pathway. The genes for flagellin, the subunit of the flagellar filament (fliC), and for the flagellar motor switch protein (fliM) were isolated based on their resemblance to these proteins in other bacteria. As is typical for flagellins, the predicted FliC protein had well-conserved N- and C-terminal regions, separated by a divergent central domain. The predicted R. solanacearum FliM closely resembled motor switch proteins from other proteobacteria. Chromosomal mutants lackingfliC or fliM were created by replacing the genes with marked interrupted constructs. Since fliM is embedded in the fliLMNOPQR operon, the aphAcassette was used to make a nonpolar fliM mutation. Both mutants were completely nonmotile on soft agar plates, in minimal broth, and in tomato plants. The fliC mutant lacked flagella altogether; moreover, sheared-cell protein preparations from the fliC mutant lacked a 30-kDa band corresponding to flagellin. The fliM mutant was usually aflagellate, but about 10% of cells had abnormal truncated flagella. In a biologically representative soil-soak inoculation virulence assay, both nonmotile mutants were significantly reduced in the ability to cause disease on tomato plants. However, the fliC mutant had wild-type virulence when it was inoculated directly onto cut tomato petioles, an inoculation method that did not require bacteria to enter the intact host from the soil. These results suggest that swimming motility makes its most important contribution to bacterial wilt virulence in the early stages of host plant invasion and colonization.

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