Susceptibility of Diaphorina citri to dimethoate and chlorpyrifos in commercial citrus orchards of Veracruz, Mexico

There are reports of Diaphorina citri resistance in the state of Veracruz to chlorpyrifos and dimethoate due to the excessive use of these products for the control of pests, among them D. citri. The purpose of this work was to diagnose the susceptibility of D. citri adults to chlorpyrifos and dimethoate in commercial citrus orchards of the municipality of Martinez de la Torre, Veracruz. For this, 200 adults of D. citri were collected in each of 30 orchards, and topical application bioassays were performed with dimethoate at 0.0090% concentration and chlorpyrifos at 0.0085% concentration. Diaphorina citri adults without chemical control during 10 years were used as a control. Mortality of D. citri with dimethoate and chlorpyrifos averaged 85%, in contrast the control mortality was 99% and 98.8% with dimethoate and chlorpyrifos, respectively. According to these results, it can be inferred that D. citri has some resistance to organophosphate insecticides in the orchards of Martinez de la Torre, Veracruz. This information can be used to decide the type of insecticides to apply in the study area.

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Factors associated with Diaphorina citri immigration into commercial citrus orchards in São Paulo State, Brazil

Journal of Applied Entomology ◽

10.1111/jen.12851 ◽

2020 ◽

Author(s):

Fernando P. F. Zorzenon ◽

Arthur F. Tomaseto ◽

Matthew P. Daugherty ◽

João R. S. Lopes ◽

Marcelo P. Miranda

Keyword(s):

Sao Paulo ◽

São Paulo ◽

Diaphorina Citri ◽

Factors Associated ◽

Paulo State ◽

São Paulo State ◽

Citrus Orchards

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Development on Infected Citrus over Generations Increases Vector Infection by ‘Candidatus Liberibacter Asiaticus in Diaphorina citri’

Insects ◽

10.3390/insects11080469 ◽

2020 ◽

Vol 11 (8) ◽

pp. 469

Author(s):

Inaiara de Souza Pacheco ◽

Diogo Manzano Galdeano ◽

João Roberto Spotti Lopes ◽

Marcos Antonio Machado

Keyword(s):

Management Strategies ◽

Fourth Generation ◽

Diaphorina Citri ◽

Candidatus Liberibacter Asiaticus ◽

Candidatus Liberibacter ◽

Citrus Huanglongbing ◽

Liberibacter Asiaticus ◽

Citrus Orchards ◽

Vector Efficiency ◽

Control And Eradication

‘Candidatus Liberibacter asiaticus’ (CLas) is a major causal agent of citrus Huanglongbing (HLB), which is transmitted by Asian citrus psyllid (ACP), Diaphorina citri, causing severe losses in various regions of the world. Vector efficiency is higher when acquisition occurs by ACP immature stages and over longer feeding periods. In this context, our goal was to evaluate the progression of CLas population and infection rate over four ACP generations that continuously developed on infected citrus plants. We showed that the frequency of CLas-positive adult samples increased from 42% in the parental generation to 100% in the fourth generation developing on CLas-infected citrus. The bacterial population in the vector also increased over generations. This information reinforces the importance of HLB management strategies, such as vector control and eradication of diseased citrus trees, to avoid the development of CLas-infected ACP generations with higher bacterial loads and, likely, a higher probability of spreading the pathogen in citrus orchards.

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Detection of Candidatus Liberibacter asiaticus from Wampee (Clausena lansium Skeels) by Nested PCR

Plant Health Progress ◽

10.1094/php-2007-0419-01-br ◽

2007 ◽

Vol 8 (1) ◽

pp. 53 ◽

Cited By ~ 3

Author(s):

Xiaoling Deng ◽

Gen Zhou ◽

Huaping Li ◽

Jianchi Chen ◽

Edwin L. Civerolo

Keyword(s):

Nested Pcr ◽

Southern China ◽

Diaphorina Citri ◽

Candidatus Liberibacter Asiaticus ◽

Term Survival ◽

Disease Vector ◽

Candidatus Liberibacter ◽

Liberibacter Asiaticus ◽

Citrus Orchards

Wampee (Clausena lansium Skeels) is native to southern China and Southeast Asia. Wampee trees are attractive, with grape-like fruits and a muscat taste and are popular in home gardens. Like other members of Rutaceae, wampee has long been suspected to have yellow shoot disease or Huanglongbing (HLB) and Diaphorina citri, the disease vector, was capable of a long-term survival on Wampee. The authors recommend that eradication of wampee trees surrounding citrus orchards should be part of the overall management of citrus HLB. Accepted for publication 20 December 2007. Published 19 April 2007.

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SEASONAL FLUCTUATION OF ASIAN CITRUS PSYLLA POPULATIONS IN THE CITRUS ORCHARDS INFECTED WITH HUANGLONGBING IN SARGODHA, PAKISTAN

Pakistan Journal of Phytopathology ◽

10.33866/phytopathol.029.01.0328 ◽

2017 ◽

Vol 29 (1) ◽

pp. 175

Author(s):

Yasir Iftikhar ◽

Imran U. Haq ◽

Waqas Raza ◽

Muhammad I. Ullah ◽

Sajjad Ali ◽

...

Keyword(s):

High Temperature ◽

Environmental Factors ◽

Minimum Temperature ◽

Management Strategy ◽

Integrated Management ◽

Seasonal Fluctuation ◽

Diaphorina Citri ◽

Citrus Production ◽

Citrus Orchards ◽

Citrus Psylla

A study on seasonal fluctuation in Citrus psylla (Diaphorina citri) (CP) population in citrus orchards infected with Huanglongbing was carried out in relation to environmental factors in six tehsils of Sargodha district. The population of citrus psylla was reached to the peak twice in a year. Young flushes favored the build-up in psylla population. Minimum temperature and rainfall had highly significant correlation with build-up in population of citrus psylla in all the six tehsils of Sargodha. Although, high temperature also favored the high population of citrus psylla in two tehsils. August and mid-March to April were the two times when population of citrus psylla reached to the peak. Therefore, an integrated management strategy can be formulated with this study that will not only help in reducing the HLB incidence but also increase in citrus production.

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Susceptibility of soybean looper to lufenuron and spinosad

Arquivos do Instituto Biológico ◽

10.1590/1808-1657000062019 ◽

2020 ◽

Vol 87 ◽

Author(s):

Lucas Ferraz de Queiroz ◽

Janaina De Nadai Corassa ◽

Sandra Maria Morais Rodrigues ◽

Rafael Major Pitta

Keyword(s):

Chemical Control ◽

Resistance Management ◽

The State ◽

Laboratory Population ◽

Mato Grosso ◽

Regional Monitoring ◽

Pest Monitoring ◽

Overlay Method ◽

Soybean Looper ◽

Chrysodeixis Includens

ABSTRACT: The soybean looper (Chrysodeixis includens) is an important defoliation pest in crops such as soybean and cotton in Brazil. Its main control tactic is chemical insecticides. Considering the importance of chemical control for this pest, monitoring the susceptibility of C. includens populations is strategic for an efficient Insect Resistance Management. Therefore, the objective of this study was to evaluate the susceptibility levels of C. includens populations in the state of Mato Grosso - Brazil to lufenuron and spinosad. Seven populations were collected in soybean fields around the state. For the bioassays, early L3 larvae were exposed to insecticides using the diet-overlay method. Although the compounds have distinct modes of action, Tangará da Serra population had the highest resistance ratios for lufenuron (11.62) and spinosad (7.84), compared to laboratory population (susceptibility reference). Even with low resistance levels, it is necessary to maintain regional monitoring of C. includens susceptibility to the evaluated insecticides, as well as to extend the range of molecules monitored.

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Yeni Tesis Mandalina Bahçesinde Malç Tekstili Uygulamasının Yabancı Ot Kontrolü ve Mandalina Gelişimine Etkileri

Turkish Journal of Agriculture - Food Science and Technology ◽

10.24925/turjaf.v5i6.568-580.729 ◽

2017 ◽

Vol 5 (6) ◽

pp. 568 ◽

Cited By ~ 1

Author(s):

Yasin Emre Kitiş ◽

Onur Kolören ◽

Feyzullah Nezihi Uygur

Keyword(s):

Leaf Area ◽

Weed Control ◽

Chemical Control ◽

General Evaluation ◽

Citrus Orchards ◽

Different Thickness ◽

Polyethylene Mulch ◽

Made In ◽

Herbicide Glyphosate ◽

Soil Temperature And Moisture

In this study, material that we call mulch textile was investigated as compared with conventional polyethylene mulch nylon and mechanical and chemical control that are widely used in farmer’s conditions to weed control in newly established citrus orchards. Two different thickness of polyethylene mulch, three different thickness of mulch textiles, mowing and herbicide (glyphosate) applications were made in newly established mandarin orchard in a three-year-period (2004-2005-2006). Effects of the applications on density and coverage of weeds and height, stem thickness and leaf area of cultural plants were investigated. According to general evaluation of results of the study, mowing 23.4%, chemical control 88.4%, polyethylene mulch 99.6%, mulch textiles 100% controlled weeds than weedy control. At the most increase of height, stem thickness and leaf area of mandarin was obtained from herbicide and mulch treatments. It was determined that soil temperature and moisture are preserved by mulch applications.

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Prevalent transmission of 'Candidatus Liberibacter asiaticus’ over ‘Ca. Liberibacter americanus’ in a long-term controlled environment

Phytopathology ◽

10.1094/phyto-06-21-0239-fi ◽

2021 ◽

Author(s):

Maria Cândida de Godoy Gasparoto ◽

Isabela Vescove Primiano ◽

Renato Bassanezi ◽

Silvia Afonseca Lourenço ◽

Luiz Montesino ◽

...

Keyword(s):

Sweet Orange ◽

Insect Vector ◽

Diaphorina Citri ◽

Candidatus Liberibacter Asiaticus ◽

Candidatus Liberibacter ◽

Citrus Huanglongbing ◽

Liberibacter Asiaticus ◽

Citrus Orchards ◽

Test Plants

In Brazil, citrus huanglongbing (HLB) is associated with ‘Candidatus Liberibacter americanus’ (CLam) and ‘Ca. Liberibacter asiaticus’ (CLas). However, there are few studies about HLB epidemiology when both Liberibacter spp. and its insect vector, the Asian citrus psyllid (ACP, Diaphorina citri), are present. The objective of this work was to compare the transmission of HLB by ACP when both CLam and CLas are present as primary inoculum. Two experiments were performed under screenhouse conditions from April 2008 to January 2012 (experiment 1) and from February 2011 to December 2015 (experiment 2). The experiments were carried out with sweet orange plants infected with CLam or CLas as inoculum source surrounded by sweet orange healthy plants. One hundred Liberibacter-free adult psyllids were monthly confined to the source of inoculum plants for 7 days with subsequent free movement inside the screenhouse. Fortnightly, nymphs and adults of psyllids were monitored. Psyllid and leaf samples were collected periodically for Liberibacter detection by PCR or qPCR. CLas was detected more frequently than CLam in both psyllid and leaf samples. No mixed infections were detected in the psyllids. A clear prevalence of CLas over CLam was observed in both experiments. The final HLB incidences were 16.7 and 14.5% of Liberibacter-positive test plants, and CLas was detected in 92.3 and 93.1% of these infected plants. Mixed infection was observed only in 3.8% of infected test plants in experiment 1. These results endorse the shift in the prevalence of CLam to CLas observed in citrus orchards of São Paulo, Brazil.

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