Detection of Pathogens Associated with Psyllids and Leafhoppers in Capsicum annuum L. in the Mexican States of Durango, Zacatecas, and Michoacán

Abstract

In fall 2014, 5 to 75% percent of chili and bell pepper (Capsicum annuum L.) in commercial fields located in the Mexican states of Durango, Zacatecas, and Michoacán had symptoms of deformed, small, mosaic, curled, and chlorotic leaves; shortened internodes; plant dwarfing; or phyllody and rosetting leaf tips. At the same time, leafhoppers and psyllids were observed in the fields, and more than 50 beet leafhoppers (Circulifer tenellus) and nearly 300 potato psyllids (Bactericera cockerelli) were collected from the pepper plants and adjacent weeds. Based on the insect pressure and observed symptoms, nearly 400 pepper samples were collected across this region of Mexico and tested for the presence of leafhopper- and psyllid-associated pathogens. In all, 76% of the pepper samples were found to be infected with ‘Candidatus Liberibacter solanacearum’, beet leafhopper-transmitted virescence agent (BLTVA) phytoplasma, a strain of a curtovirus, or a combination of any two or three of these pathogens. Additionally, 77% of the collected leafhoppers and 40% of the psyllids were infected with one or more of these pathogens, in addition to Spiroplasma citri. Specifically, the leafhoppers were infected with BLTVA phytoplasma, S. citri, or a strain of curtovirus. Of particular interest, potato psyllids were not only infected with ‘Ca. L. solanacearum’ but also with phytoplasmas that belong to the groups 16SrVI subgroup A and 16SrI subgroup A. The presence of mixed infections in pepper plants and the insect vectors highlights the need for growers to effectively control both leafhoppers and potato psyllids from solanaceous crops in this region of Mexico in order to prevent the spread of these bacterial and viral pathogens.

Investigation on phytoplasma diseases, their potential insect vectors and other hosts in pepper (Capsicum annuum L.) growing areas of Hatay-Turkey

“…In this study, the phytoplasma determined species, the number of tested insects and the determined phytoplasmas in pepper fields are given in Table 2. (Swisher et al, 2018), Iran MK379605 (Babaei et al 2020) and MG788318 (unpublished data), 99.60% similarity rate to Iran isolate JF508509 (Jamshidi et al 2014). The isolate MT992796 identified as Ca.…”

Ecology‐based analysis of a recent association between Spartium junceum and 16SrV phytoplasma

“…Mixed infections confirmed that the two phytoplasmas were actively acquired and mixed infection rates of about 24% were recorded. Mixed infections of phytoplasmas in vector insects are quite common (Bosco and D'Amelio, 2010), and, among psyllids, Bactericera cockerelli can host more than one phytoplasma species (16SrI-A and VI-A), together with the unrelated 'Candidatus Liberibacter solanacearum', with frequencies of up to 40% (Swisher et al, 2018). (Queiroz et al, 2016) are challenging this assumption.…”

Multiple guests in a single host: interactions across symbiotic and phytopathogenic bacteria in phloem‐feeding vectors – a review

“…Mixed infections by bacterial pathogens are commonly observed in the phloem of a single plant. The simultaneous occurrence of multiple pathogens, either related or phylogenetically distant, is rather frequent in single herbaceous plants and trees of many families (Križanac et al., ; Nicolaisen et al., ; Arratia‐Castro et al., ; Satta et al., ; Swisher et al., ). Throughout its life cycle, a single insect may feed on several plants of the same or different species, probably being exposed to mixed pathogen infections.…”

“…Throughout its life cycle, a single insect may feed on several plants of the same or different species, probably being exposed to mixed pathogen infections. As a consequence, insect vectors may acquire many pathogen species or strains during a feeding event, or by feeding sequentially on host plants infected by different bacteria (Križanac et al., ; Raddadi et al., ; Swisher et al., ) (Table ). In some cases, the co‐occurrence of multiple pathogens in an insect's body is inhibited by interferential interactions such as selective acquisition or transmission of a single microbe (Bosco & D'Amelio, ).…”