scholarly journals Ocorrência de doenças do tomateiro na região de Guanambi, BA

Author(s):  
M. A. S. Guimarães ◽  
J. H. S. Teixeira ◽  
S. C. Cardoso

<p>As doenças do tomateiro são responsáveis por grandes prejuízos econômicos e a falta de conhecimento técnico no diagnóstico e controle dessas doenças onera os custos e limitam a sua produção. Esse trabalho tem como objetivo realizar um levantamento para identificação e registro de ocorrência de doenças do tomateiro na região de Guanambi, BA. O levantamento foi realizado nos Distritos de Morrinhos e Guirapá e nos Povoados de Brejos dos Padres e do Tanque. Para tanto, foram realizadas visitas nas áreas produtoras de tomate e para avaliação do histórico da área foi aplicado um questionário aos produtores. Amostras de plantas infectadas foram coletadas e levadas para análise no Laboratório de Fitopatologia do IFBaiano - Campus Guanambi ou enviadas para diagnóstico em Clinica Fitopatológica. Foram diagnosticadas nove doenças bióticas: vira cabeça do tomateiro (<em>Tomato spotted wilt virus</em>), oídio (<em>Oidium </em>sp.), murcha de fusário (<em>Fusarium oxysporum</em>), requeima (<em>Phytophthora infestans</em>), mofo preto (<em>Alternaria alternata</em>), mancha de estenfílio (<em>Stemphylium </em>sp.), mancha de cladospório (<em>Fulvia fulva</em>), pinta-preta (<em>Alternaria solani</em>) e murcha bacteriana (<em>Ralstonia solanacearum</em>); e três doenças abióticas (podridão apical, deficiência de fósforo e murcha por asfixia) nos cultivos de tomate. Dentre as doenças bióticas encontradas, o vira cabeça do tomateiro e o oídio foram as mais frequentes. </p><p align="center"><strong><em>Occurrence of diseases in tomato in the region of Guanambi, Bahia</em></strong></p><p><strong>Abstract</strong><strong>: </strong>The tomato diseases are responsible for great economic losses and the lack of technical knowledge in the diagnosis and control of these diseases onerous costs and limit their production. This work aims to conduct a survey to identify and record of the tomato diseases occurrence in the Guanambi region, Bahia state. The survey was conducted in Morrinhos, Guirapá, Brejo dos Padres and Tanque Districts. Therefore, visits were made in tomato producing areas and for the evaluation of the area historic have been applied a questionnaire to farmers. Samples of infected plants were collected and sent for analysis at the Laboratory of Phytopathology, IFBaiano - <em>Campus</em> Guanambi or sent for diagnosis in Clinic Phytopathologic. Were diagnosed nine biotic diseases: Tospovirus (<em>Tomato spotted wilt virus</em>), powdery mildew (<em>Oidium </em>sp.<em>)</em>, Fusarium wilt (<em>Fusarium oxysporum</em>), late blight (<em>Phytophthora infestans</em>), black mold (<em>Alternaria alternata</em>), Stemphylium leaf blight (<em>Stemphylium </em>sp.), leaf mold (<em>Fulvia fulva</em>), blight (<em>Alternaria solani</em>) and bacterial wilt (<em>Ralstonia solanacearum</em>), and three abiotic diseases (blossom-end rot, phosphorus deficiency and withered by suffocation) in the tomato crops. Among the biotic diseases found, o <em>Tomato spotted wilt virus</em> and <em>Oidium </em>sp. were the most frequent.</p><p><strong> </strong></p>

HortScience ◽  
2010 ◽  
Vol 45 (10) ◽  
pp. 1424-1428 ◽  
Author(s):  
Matthew D. Robbins ◽  
Mohammed A.T. Masud ◽  
Dilip R. Panthee ◽  
Randolph G. Gardner ◽  
David M. Francis ◽  
...  

Tomato spotted wilt virus (TSWV) and Phytophthora infestans (late blight) in tomato (Solanum lycopersicum) have a worldwide distribution and are known to cause substantial disease damage. Sw-5 (derived from S. peruvianum) and Ph-3 (derived from S. pimpinellifolium) are, respectively, TSWV and late blight resistance genes. These two genes are linked (within 5 cM on several maps) in repulsion phase near the telomere of the long arm on chromosome 9. The tomato lines NC592 (Ph-3) and NC946 (Sw-5) were crossed to develop an F2 population and subsequent inbred generations. Marker-assisted selection (MAS) using three polymerase chain reaction-based codominant markers (TG328, TG591, and SCAR421) was used in F2 progeny with the goal of selecting for homozygous coupling-phase recombinant lines. From 1152 F2 plants, 11 were identified with potential recombination events between Ph-3 and Sw-5; of those, three were male sterile (ms-10). F3 progeny were generated from the remaining eight F2 recombinants, and resistance to both pathogens, or Ph-3 and Sw-5 in coupling phase, was confirmed in three of those. Recombination was suppressed fivefold in our F2 population to 1.11 cM between genes when compared with published maps of the same region. However, MAS was an efficient tool for selecting the desirable recombination events for these two pathogen resistance genes.


Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 320
Author(s):  
Alexander Nilon ◽  
Karl Robinson ◽  
Hanu R. Pappu ◽  
Neena Mitter

Tomato spotted wilt virus (TSWV) is the type member of the genus Orthotospovirus in the family Tospoviridae and order Bunyavirales. TSWV, transmitted by several species of thrips, causes significant disease losses to agronomic and horticultural crops worldwide, impacting both the yield and quality of the produce. Management strategies include growing virus-resistant cultivars, cultural practices, and managing thrips vectors through pesticide application. However, numerous studies have reported that TSWV isolates can overcome host-plant resistance, while thrips are developing resistance to pesticides that were once effective. RNA interference (RNAi) offers a means of host defence by using double-stranded (ds) RNA to initiate gene silencing against invading viruses. However, adoption of this approach requires production and use of transgenic plants and thus limits the practical application of RNAi against TSWV and other viruses. To fully utilize the potential of RNAi for virus management at the field level, new and novel approaches are needed. In this review, we summarize RNAi and highlight the potential of topical or exogenous application of RNAi triggers for managing TSWV and thrips vectors.


Nature ◽  
1964 ◽  
Vol 203 (4945) ◽  
pp. 671-672 ◽  
Author(s):  
RUPERT J. BEST ◽  
GERARD F. KATEKAR

Sign in / Sign up

Export Citation Format

Share Document