Reaction of Capsicum peppers commercialized in the Federal District to bacterial wilt

Abstract

In Brazil, the bacterial pathogens Ralstonia solanacearum and R. pseudosolanacearum cause substantial losses by inducing bacterial wilt on several solanaceous crops; R. pseudosolanacearum is the main species associated with peppers (Capsicum sp.). To verify the bacterial wilt reaction on Capsicum peppers commercialized in the Federal District (DF), fruits of several genotypes within this genus were collected from six different fairs distributed in the satellite cities of Gama, Sobradinho and Guará. Seedlings with four true leaves derived from seeds extracted from such fruits were root inoculated with 108 CFU/mL with a representative isolate of R. pseudosolanacearum (race 1, biovar 3, phylotype I, sequevar 18). The evaluated species were: Capsicum frutescens (‘pimenta-malagueta’), Capsicum baccatum var. pendulum (‘pimenta-dedo-de-moça’) and C. chinense (‘pimenta-de-bode’ red and yellow, ‘pimenta-cumarí-do-Pará’, ‘pimenta-biquinho’, ‘pimenta-habanero’ and ‘pimenta-de-cheiro’). Not all species were found in all six fairs. The reaction to bacterial wilt was variable and species-dependent. From 26 evaluated genotypes, none presented an immune-like response, 10 were considered resistant and 16 susceptible based on wilt incidence (Scott-Knott, 5%). Four Capsicum baccatum accesses were positioned in the resistant group, whereas 14 out of 18 of C. chinense were susceptible. Capsicum frutescens showed variable reactions. These results contribute to indicate cultivation of specific groups of pepper according to the presence of the pathogen in the soil.

Reaction of advanced inbred lines of Habanero pepper to Ralstonia pseudosolanacearum and Phytophthora capsici

“…The main soilborne pathogens of pepper plants reported are Ralstonia pseudosolanacearum sp. (RP; Lebeau et al, 2011;Granke et al, 2012;Rossato et al, 2018), Phytophthora capsici (PC; Gilardi et al, 2013;Reeves et al, 2013;Sánchez-Chávez et al, 2017), presented in this study, and Meloidogyne nematodes (Pinheiro et al, 2014), which cause bacterial wilt, phytophthora blight and root knot, respectively.…”

“…T h e b a c t e r i u m R a l s t o n i a pesudosolanacearum originates from the recent taxonomic reorganization of R. solanacearum, previously identified as race 1 biovar 3, phylotype I (Rossato et al, 2018). This species is more aggressive than R. solanacearum (races 1, 2, 3, biovars 1, 2, phylotype II) on Capsicum, and presents higher evolution rates and the largest geographical distribution worldwide (Lopes & Boiteux, 2004;Rossato et al, 2018). This fact was also noticed under natural conditions in the Amazon region (Coelho Netto et al, 2004).…”

“…Sources of resistance to these two diseases were identified in accessions of Capsicum spp. (Madeira et al, 2016;Petry et al, 2016, Rossato et al, 2018. Currently, the hybrid rootstock BRS Acará developed by Embrapa Hortaliças, has shown multiple resistance to several isolates of P. capsici and R. pseudosolanacearum, besides Meloidogyne incognita (Madeira et al, 2016).…”

“…These isolates were collected in different regions of Brazil, in Dom Pedro-MA, Guadalupe-PI and Altamira-PA, respectively. Inocula were prepared using the methodology described by Rossato et al (2018).…”

Comparison of polynomial and nonlinear models on description of pepper growth

“…Pepper consumption is made in form of naturally preserved, sauces, spices, jellies, paprika and in natura. The crop is produced in all regions of Brazil, mostly by small farmers, with the states of Minas Gerais, Goiás, São Paulo, Ceará and Rio Grande do Sul as the largest producers (Santana et al, 2017;Rossato et al, 2018).…”