scholarly journals Genome-Wide Identification of Ralstonia solanacearum Genes Required for Survival in Tomato Plants

mSystems ◽  
2021 ◽  
Author(s):  
Yaxing Su ◽  
Yanan Xu ◽  
Hailing Liang ◽  
Gaoqing Yuan ◽  
Xiaogang Wu ◽  
...  
Keyword(s):  
Ralstonia Solanacearum ◽  
Tomato Plant ◽  
Pathogenic Mechanism ◽  
Hostile Environment ◽  
Full Understanding ◽  
Tomato Plants ◽  
Content Type ◽  
Genome Wide

Tomato plant xylem is a nutritionally limiting and dynamically changing habitat. Studies on how R. solanacearum survives in this hostile environment are important for our full understanding of the pathogenic mechanism of this bacterium.

scholarly journals Biocontrol of Ralstonia solanacearum by Treatment with Lytic Bacteriophages

2011 ◽  
Vol 77 (12) ◽  
pp. 4155-4162 ◽  
Author(s):  
Akiko Fujiwara ◽  
Mariko Fujisawa ◽  
Ryosuke Hamasaki ◽  
Takeru Kawasaki ◽  
Makoto Fujie ◽  
...  
Keyword(s):  
Cell Density ◽  
Ralstonia Solanacearum ◽  
Experimental Period ◽  
The Other ◽  
Bacterial Cells ◽  
Effective Prevention ◽  
Tomato Plants ◽  
Content Type ◽  
Tomato Seedlings ◽  
Lower Cell Density

ABSTRACTRalstonia solanacearumis a Gram-negative bacterium and the causative agent of bacterial wilt in many important crops. We treatedR. solanacearumwith three lytic phages: φRSA1, φRSB1, and φRSL1. Infection with φRSA1 and φRSB1, either alone or in combination with the other phages, resulted in a rapid decrease in the host bacterial cell density. Cells that were resistant to infection by these phages became evident approximately 30 h after phage addition to the culture. On the other hand, cells infected solely with φRSL1 in a batch culture were maintained at a lower cell density (1/3 of control) over a long period. Pretreatment of tomato seedlings with φRSL1 drastically limited penetration, growth, and movement of root-inoculated bacterial cells. All φRSL1-treated tomato plants showed no symptoms of wilting during the experimental period, whereas all untreated plants had wilted by 18 days postinfection. φRSL1 was shown to be relatively stable in soil, especially at higher temperatures (37 to 50°C). Active φRSL1 particles were recovered from the roots of treated plants and from soil 4 months postinfection. Based on these observations, we propose an alternative biocontrol method using a unique phage, such as φRSL1, instead of a phage cocktail with highly virulent phages. Using this method, φRSL1 killed some but not all bacterial cells. The coexistence of bacterial cells and the phage resulted in effective prevention of wilting.

scholarly journals Ralstonia solanacearum Requires PopS, an Ancient AvrE-Family Effector, for Virulence and To Overcome Salicylic Acid-Mediated Defenses during Tomato Pathogenesis

mBio ◽  
2013 ◽  
Vol 4 (6) ◽  
Author(s):  
Jonathan M. Jacobs ◽  
Annett Milling ◽  
Raka M. Mitra ◽  
Clifford S. Hogan ◽  
Florent Ailloud ◽  
...  
Keyword(s):  
Salicylic Acid ◽  
Bacterial Wilt ◽  
Ralstonia Solanacearum ◽  
Species Complex ◽  
Plant Defenses ◽  
Natural Infection ◽  
Wild Type ◽  
Tomato Plants ◽  
Content Type ◽  
Type Iii

ABSTRACTDuring bacterial wilt of tomato, the plant pathogen Ralstonia solanacearum upregulates expression ofpopS, which encodes a type III-secreted effector in the AvrE family. PopS is a core effector present in all sequenced strains in theR. solanacearumspecies complex. The phylogeny ofpopSmirrors that of the species complex as a whole, suggesting that this is an ancient, vertically inherited effector needed for association with plants. ApopSmutant ofR. solanacearumUW551 had reduced virulence on agriculturally importantSolanumspp., including potato and tomato plants. However, thepopSmutant had wild-type virulence on a weed host,Solanum dulcamara, suggesting that some species can avoid the effects of PopS. ThepopSmutant was also significantly delayed in colonization of tomato stems compared to the wild type. Some AvrE-type effectors from gammaproteobacteria suppress salicylic acid (SA)-mediated plant defenses, suggesting that PopS, a betaproteobacterial ortholog, has a similar function. Indeed, thepopSmutant induced significantly higher expression of tomato SA-triggered pathogenesis-related (PR) genes than the wild type. Further, pretreatment of roots with SA exacerbated thepopSmutant virulence defect. Finally, thepopSmutant had no colonization defect on SA-deficient NahG transgenic tomato plants. Together, these results indicate that this conserved effector suppresses SA-mediated defenses in tomato roots and stems, which areR. solanacearum’s natural infection sites. Interestingly, PopS did not trigger necrosis when heterologously expressed inNicotianaleaf tissue, unlike the AvrE homolog DspEPccfrom the necrotrophPectobacterium carotovorumsubsp.carotovorum. This is consistent with the differing pathogenesis modes of necrosis-causing gammaproteobacteria and biotrophicR. solanacearum.IMPORTANCEThe type III-secreted AvrE effector family is widely distributed in high-impact plant-pathogenic bacteria and is known to suppress plant defenses for virulence. We characterized the biology of PopS, the only AvrE homolog made by the bacterial wilt pathogenRalstonia solanacearum. To our knowledge, this is the first study ofR. solanacearumeffector function in roots and stems, the natural infection sites of this pathogen. Unlike the functionally redundantR. solanacearumeffectors studied to date, PopS is required for full virulence and wild-type colonization of two natural crop hosts.R. solanacearumis a biotrophic pathogen that causes a nonnecrotic wilt. Consistent with this, PopS suppressed plant defenses but did not elicit cell death, unlike AvrE homologs from necrosis-causing plant pathogens. We propose that AvrE family effectors have functionally diverged to adapt to the necrotic or nonnecrotic lifestyle of their respective pathogens.

scholarly journals Twitching and Swimming Motility Play a Role in Ralstonia solanacearum Pathogenicity

mSphere ◽  
2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Jordi Corral ◽  
Pau Sebastià ◽  
Núria S. Coll ◽  
Jordi Barbé ◽  
Jesús Aranda ◽  
...  
Keyword(s):  
Plant Pathogen ◽  
Ralstonia Solanacearum ◽  
Biofilm Formation ◽  
Natural Transformation ◽  
Plant Colonization ◽  
Twitching Motility ◽  
Tomato Plants ◽  
Content Type ◽  
First Time ◽  
Root Attachment

ABSTRACT Ralstonia solanacearum is a bacterial plant pathogen causing important economic losses worldwide. In addition to the polar flagella responsible for swimming motility, this pathogen produces type IV pili (TFP) that govern twitching motility, a flagellum-independent movement on solid surfaces. The implication of chemotaxis in plant colonization, through the control flagellar rotation by the proteins CheW and CheA, has been previously reported in R. solanacearum. In this work, we have identified in this bacterium homologues of the Pseudomonas aeruginosa pilI and chpA genes, suggested to play roles in TFP-associated motility analogous to those played by the cheW and cheA genes, respectively. We demonstrate that R. solanacearum strains with a deletion of the pilI or the chpA coding region show normal swimming and chemotaxis but altered biofilm formation and reduced twitching motility, transformation efficiency, and root attachment. Furthermore, these mutants displayed wild-type growth in planta and impaired virulence on tomato plants after soil-drench inoculations but not when directly applied to the xylem. Comparison with deletion mutants for pilA and fliC—encoding the major pilin and flagellin subunits, respectively—showed that both twitching and swimming are required for plant colonization and full virulence. This work proves for the first time the functionality of a pilus-mediated pathway encoded by pil-chp genes in R. solanacearum, demonstrating that pilI and chpA genes are bona fide motility regulators controlling twitching motility and its three related phenotypes: virulence, natural transformation, and biofilm formation. IMPORTANCE Twitching and swimming are two bacterial movements governed by pili and flagella. The present work identifies for the first time in the Gram-negative plant pathogen Ralstonia solanacearum a pilus-mediated chemotaxis pathway analogous to that governing flagellum-mediated chemotaxis. We show that regulatory genes in this pathway control all of the phenotypes related to pili, including twitching motility, natural transformation, and biofilm formation, and are also directly implicated in virulence, mainly during the first steps of the plant infection. Our results show that pili have a higher impact than flagella on the interaction of R. solanacearum with tomato plants and reveal new types of cross-talk between the swimming and twitching motility phenotypes: enhanced swimming in bacteria lacking pili and a role for the flagellum in root attachment.

scholarly journals Specific Environmental Temperature and Relative Humidity Conditions and Grafting Affect the Persistence and Dissemination of Salmonella enterica subsp. enterica Serotype Typhimurium in Tomato Plant Tissues

2019 ◽  
Vol 85 (11) ◽  
Author(s):  
Loïc Deblais ◽  
Yosra A. Helmy ◽  
Anna Testen ◽  
Claudio Vrisman ◽  
Alejandra M. Jimenez Madrid ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Environmental Conditions ◽  
Tomato Plant ◽  
Salmonella Enterica ◽  
Environmental Temperature ◽  
Abiotic Factors ◽  
Root Systems ◽  
Plant Tissues ◽  
Tomato Plants ◽  
Content Type

ABSTRACT Little is known about the abiotic factors contributing to the preharvest persistence of Salmonella in tomato tissues. Therefore, we investigated the effects of specific environmental conditions and contamination methods on the persistence and dissemination of Salmonella enterica subsp. enterica serotype Typhimurium (JSG626) in tomato plants. When plants were sprayed on the leaves with a JSG626-contaminated solution, JSG626 persistence in the phyllosphere (bacteria located on the surface of the inoculated foliage and stem tissues) was lower at higher temperatures (30°C day/25°C night) than at lower temperatures (20°C day/15°C night). However, wounding cotyledons with contaminated tools improved JSG626 persistence and the internalization rate (2.27%) in planta compared to spray inoculation (0.004%). The systemic dissemination of JSG626 to other tissues increased when contaminated plants were grown under low relative humidity (<40%); however, JSG626 was only detected in the root systems at later sampling times (between 21 and 98 days postinoculation [dpi]). Further, after tomato scions were grafted onto rootstocks using contaminated cutting tools, dissemination of JSG626 was preferentially basipetal and occasionally acropetal in the plants, with higher persistence rates and loads of JSG626 in root systems compared to foliar tissues. JSG626 was detected in the grafting point and root systems up to 242 dpi; however, none of the fruits harvested from contaminated plants between 90 and 137 dpi were positive for JSG626. This study demonstrates that environmental temperature and relative humidity could be good indicators for estimating the persistence of Salmonella enterica in tomato plants. Further, root systems may represent a risk for long-term persistence of Salmonella enterica in tomato plants. IMPORTANCE Tomatoes are one of the most widely produced vegetables around the world; however, fresh tomatoes have been connected to multiple wide-scale salmonellosis outbreaks over the past decades. Salmonella is commonly found in the environment and can persist in hostile conditions for several weeks before being internalized into plant tissues, where it is protected from conventional sanitation methods. In addition to biotic factors (host, inoculum size, and phytobiome), abiotic factors (environmental conditions) may affect the persistence of Salmonella in crop production. This study demonstrates that specific environmental conditions, the inoculation method, and the inoculum density affect the persistence and dissemination of JSG626 in tomato plant tissues. Our findings enhance the understanding of interactions between Salmonella enterica and fresh produce and may lead to the development of novel management practices on farms.

scholarly journals Ralstonia solanacearum Needs Motility for Invasive Virulence on Tomato

2001 ◽  
Vol 183 (12) ◽  
pp. 3597-3605 ◽  
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.

Genome analysis reveals that the correct name of type strain Adlercreutzia caecicola DSM 22242T is Parvibacter caecicola Clavel et al. 2013

2021 ◽  
Vol 71 (5) ◽  
Author(s):  
Dominic A. Stoll ◽  
Nicolas Danylec ◽  
Christina Grimmler ◽  
Sabine E. Kulling ◽  
Melanie Huch
Keyword(s):  
Type Strain ◽  
Type Species ◽  
Draft Genome ◽  
Amino Acid Identity ◽  
Average Nucleotide Identity ◽  
Content Type ◽  
Link Type ◽  
Genome Wide ◽  
Average Amino Acid Identity ◽  
Biochemical Analyses

The strain Adlercreutzia caecicola DSM 22242T (=CCUG 57646T=NR06T) was taxonomically described in 2013 and named as Parvibacter caecicola Clavel et al. 2013. In 2018, the name of the strain DSM 22242T was changed to Adlercreutzia caecicola (Clavel et al. 2013) Nouioui et al. 2018 due to taxonomic investigations of the closely related genera Adlercreutzia, Asaccharobacter and Enterorhabdus within the phylum Actinobacteria . However, the first whole draft genome of strain DSM 22242T was published by our group in 2019. Therefore, the genome was not available within the study of Nouioui et al. (2018). The results of the polyphasic approach within this study, including phenotypic and biochemical analyses and genome-based taxonomic investigations [genome-wide average nucleotide identity (gANI), alignment fraction (AF), average amino acid identity (AAI), percentage of orthologous conserved proteins (POCP) and genome blast distance phylogeny (GBDP) tree], indicated that the proposed change of the name Parvibacter caecicola to Adlercreutzia caecicola was not correct. Therefore, it is proposed that the correct name of Adlercreutzia caecicola (Clavel et al. 2013) Nouioui et al. 2018 strain DSM 22242T is Parvibacter caecicola Clavel et al. 2013.

scholarly journals Interactions with Hosts at Cool Temperatures, Not Cold Tolerance, Explain the Unique Epidemiology of Ralstonia solanacearum Race 3 Biovar 2

2009 ◽  
Vol 99 (10) ◽  
pp. 1127-1134 ◽  
Author(s):  
Annett Milling ◽  
Fanhong Meng ◽  
Timothy P. Denny ◽  
Caitilyn Allen
Keyword(s):  
North American ◽  
Ralstonia Solanacearum ◽  
Potato Tubers ◽  
In Planta ◽  
Plant Host ◽  
Tomato Plants ◽  
North American Strain ◽  
Tropical Highlands ◽  
American Strain ◽  
Warm Temperate

Most strains of the bacterial wilt pathogen Ralstonia solanacearum are tropical, but race 3 biovar 2 (R3bv2) strains can attack plants in temperate zones and tropical highlands. The basis of this distinctive ecological trait is not understood. We compared the survival of tropical, R3bv2, and warm-temperate North American strains of R. solanacearum under different conditions. In water at 4°C, North American strains remained culturable the longest (up to 90 days), whereas tropical strains remained culturable for the shortest time (≈40 days). However, live/dead staining indicated that cells of representative strains remained viable for >160 days. In contrast, inside potato tubers, R3bv2 strain UW551 survived >4 months at 4°C, whereas North American strain K60 and tropical strain GMI1000 were undetectable after <70 days in tubers. GMI1000 and UW551 grew similarly in minimal medium at 20 and 28°C and, although both strains wilted tomato plants rapidly at 28°C, UW551 was much more virulent at 20°C, killing all inoculated plants under conditions where GMI100 killed just over half. Thus, differences among the strains in the absence of a plant host were not predictive of their behavior in planta at cooler temperatures. These data indicate that interaction with plants is required for expression of the temperate epidemiological trait of R3bv2.

scholarly journals Clonal Lineages of Erysipelothrix rhusiopathiae Responsible for Acute Swine Erysipelas in Japan Identified by Using Genome-Wide Single-Nucleotide Polymorphism Analysis

2017 ◽  
Vol 83 (11) ◽  
Author(s):  
Yohsuke Ogawa ◽  
Kazumasa Shiraiwa ◽  
Yoshitoshi Ogura ◽  
Tadasuke Ooka ◽  
Sayaka Nishikawa ◽  
...  
Keyword(s):  
Polymorphism Analysis ◽  
Whole Genome ◽  
Sequencing Analysis ◽  
Erysipelothrix Rhusiopathiae ◽  
Single Nucleotide ◽  
Content Type ◽  
Genome Wide ◽  
Wide Range ◽  
Swine Erysipelas ◽  
Lineage Iv

ABSTRACTErysipelothrix rhusiopathiaecauses swine erysipelas, an important infectious disease in the swine industry. In Japan, the incidence of acute swine erysipelas due toE. rhusiopathiaeserovar 1a has recently increased markedly. To study the genetic relatedness of the strains from the recent cases, we analyzed 34E. rhusiopathiaeserovar 1a swine isolates collected between 1990 and 2011 and further investigated the possible association of the live Koganei 65-0.15 vaccine strain (serovar 1a) with the increase in cases. Pulsed-field gel electrophoresis analysis revealed no marked variation among the isolates; however, sequencing analysis of a hypervariable region in the surface-protective antigen A gene (spaA) revealed that the strains isolated after 2007 exhibited the samespaAgenotype and could be differentiated from older strains. Phylogenetic analysis based on genome-wide single-nucleotide polymorphisms (SNPs) revealed that the Japanese strains examined were closely related, showing a relatively small number of SNPs among them. The strains were classified into four major lineages, with Koganei 65-0.15 (lineage III) being phylogenetically separated from the other three lineages. The strains isolated after 2007 and the two older strains constituted one major lineage (lineage IV) with a specificspaAgenotype (M203/I257-SpaA), while the recent isolates were further divided into two geographic groups. The remaining older isolates belonged to either lineage I, with the I203/L257-SpaA type, or lineage II, with the I203/I257-SpaA type. These results indicate that the recent increased incidence of acute swine erysipelas in Japan is associated with two sublineages of lineage IV, which have independently evolved in two different geographic regions.IMPORTANCEUsing large-scale whole-genome sequence data fromErysipelothrix rhusiopathiaeisolates from a wide range of hosts and geographic origins, a recent study clarified the existence of three distinct clades (clades 1, 2, and 3) that are found across multiple continents and host species, representing both livestock and wildlife, and an “intermediate” clade between clade 2 and the dominant clade 3 within the species. In this study, we found that theE. rhusiopathiaeJapanese strains examined exhibited remarkably low levels of genetic diversity and confirmed that all of the Japanese and Chinese swine isolates examined in this study belong to clonal lineages within the intermediate clade. We report thatspaAgenotyping ofE. rhusiopathiaestrains is a practical alternative to whole-genome sequencing analysis of theE. rhusiopathiaeisolates from eastern Asian countries.

scholarly journals DESENVOLVIMENTO DO TOMATEIRO INDUSTRIAL EM RESPOSTA A DIFERENTES NÍVEIS DE IRRIGAÇÃO

Irriga ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 432-448
Author(s):  
Cícero José da Silva ◽  
José Antônio Frizzone ◽  
César Antônio da Silva ◽  
Nadson de Carvalho Pontes ◽  
Luiz Felipe Mariano da Silva ◽  
...  
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Plant Development ◽  
Tomato Plant ◽  
Dry Mass ◽  
Area Index ◽  
Tomato Plants ◽  
Subsurface Drip ◽  
Irrigation Levels ◽  
E Mail

DESENVOLVIMENTO DO TOMATEIRO INDUSTRIAL EM RESPOSTA A DIFERENTES NÍVEIS DE IRRIGAÇÃO     Cícero José da Silva1; José Antônio Frizzone2; César Antônio da Silva3; Nadson de Carvalho Pontes4; Luiz Felipe Mariano da Silva5 E Ênio Eduardo Basílio6   1Professor do Curso Bacharelado em Agronomia, Instituto Federal Goiano – Campus Morrinhos – GO, BR 153, Km 633, Zonal Rural, CEP;75650-000, Morrinhos – GO, Brasil. E-mail: [email protected] 2Professor Aposentado Colaborador Senior, Departamento de Engenharia de Biossitemas, Escola Superior de Agricultura “Luiz de Queiroz” – Universidade de São Paulo, Avenida Pádua Dias, N 11, Caixa Postal 9, CEP: 13418-900, Piracicaba – SP, Brasil. E-mail: [email protected] 3Professor do Curso Bacharelado em Agronomia, Instituto Federal Goiano – Campus Morrinhos – GO, BR 153, Km 633, Zonal Rural, CEP;75650-000, Morrinhos – GO, Brasil. E-mail: [email protected] 4Professor do Curso Bacharelado em Agronomia, Instituto Federal Goiano – Campus Morrinhos – GO, BR 153, Km 633, Zonal Rural, CEP;75650-000, Morrinhos – GO, Brasil. E-mail: [email protected] 5Estudante de Iniciação Científica do Curso Bacharelado em Agronomia, Instituto Federal Goiano – Campus Morrinhos – GO, BR 153, Km 633, Zonal Rural, CEP;75650-000, Morrinhos – GO, Brasil. E-mail: [email protected] 6Técnico Administrativo, Mestre em Olericultura, Instituto Federal Goiano – Campus Morrinhos – GO, BR 153, Km 633, Zonal Rural, CEP;75650-000, Morrinhos – GO, Brasil. E-mail: [email protected]     1 RESUMO   O objetivo desta pesquisa foi avaliar o desenvolvimento de plantas de tomateiros submetidas a diferentes níveis de reposição da irrigação, aplicados via sistema gotejamento subsuperficial durante duas safras. O experimento foi conduzido no delineamento em blocos ao acaso, com quatro repetições. Foram avaliados cinco níveis de irrigação: 50, 75, 100, 125 e 150% da evapotranspiração da cultura (%ETc) medida com lisímetros de pesagem, sobre o desenvolvimento de plantas de tomateiro. Cada parcela experimental foi composta por três fileiras de plantas de 5,5 m de comprimento, espaçadas a 1,10 m entre si e 0,30 m entre plantas. As avaliações de área foliar, índice de área foliar, massa seca de raiz, caule, folhas, flores, frutos e total foram realizadas aos 45, 65 e 85 dias após o transplante das mudas. Irrigações deficitárias e em excesso prejudicaram o desenvolvimento vegetativo das plantas de tomateiro. Os maiores valores de área foliar, índice de área foliar e massa seca total das plantas de tomateiro foram estimados com níveis de irrigação que variaram de 96 a 112% da ETc, variando de acordo com o ano de avaliação e a fase de desenvolvimento do tomateiro. Irrigações deficitárias e excessivas prejudicaram a floração e frutificação do tomateiro híbrido BRS Sena.             Palavras-chave: Solanum lycopersicom L.; gotejamento enterrado; manejo da irrigação; massa seca.             Silva, c. j. da; FRIZZONE, J. A.; SILVA, C. A. da; pontes, n. de C.; SILVA, L. F. M. da; BASÍLIO, Ê. E. Industrial tomato plant development in response to different irrigation levels    2 ABSTRACT   This research aimed to evaluate tomato plant development submitted to different irrigation replacement levels, irrigated via subsurface drip system for two harvests. The experiment was conducted under a randomized complete block design with four replications. Five irrigation levels were evaluated: 50, 75, 100, 125 and 150% of crop evapotranspiration (% ETc) measured with weighing lysimeters over the tomato plants development. Each experimental plot was composed of three plants rows with 5.5 m long, spaced 1.10 m apart and 0.30 m between plants. Leaf area, leaf area index, root dry matter, stem, leaves, flowers, fruits and total were evaluated at 45, 65 and 85 days after seedlings transplanting. Deficit and excess irrigation impaired the vegetative development of tomato plants. The highest values of leaf area, leaf area index and plants total dry mass were estimated with irrigation levels ranging from 96 to 112% of ETc, depending on the evaluation harvest year and the crop development phase. Deficit and excessive irrigation affected the flowering and fruiting of the hybrid tomato BRS Sena.   Keywords: Solanum lycopersicom L; subsurface drip irrigation; irrigation manegement; dry mass.

scholarly journals Selection and Inheritance of Tomato Resistance against Ralstonia solanacearum

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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