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The tomato chlorosis virus (ToCV), transmitted by whitefly species of the genera Bemisia and Trialeurodes in a semipersistent manner, causes significant losses in solanaceous crops including tomato (Solanum lycopersicum) and sweet pepper (Capsicum annuum). Worldwide reports of natural and experimental infection of sweet pepper plants with ToCV are contradictory, raising the question of whether the critical factor determining infection is related to the susceptibility of sweet pepper cultivars or the genetics of virus isolates. In this work, ToCV isolates obtained from different hosts and geographical origins were biologically and molecularly analysed, transmitted by B. tabaci MEAM1 and MED, and the reaction of different sweet pepper cultivars was evaluated under different environmental conditions. Brazilian ToCV isolates from tomato, potato (S. tuberosum), S. americanum, and Physalis angulata did not infect plants of five sweet pepper cultivars when transmitted by B. tabaci MEAM1. Temperatures did not affect the sweet pepper susceptibility to tomato‐ToCV isolates from São Paulo, Brazil, and Florida, USA. However, sweet pepper‐ToCV isolates from Spain and São Paulo, Brazil, were transmitted efficiently to sweet pepper plants by B. tabaci MEAM1 and MED. Although the results indicated that ToCV isolates from naturally infected sweet pepper plants seem to be better adapted to plants of C. annuum, phylogenetic analyses based on the complete nucleotide sequences of RNA1 and RNA2 as well as the p22 gene did not reveal significant nucleotide differences among them. Additional studies are needed to identify intrinsic characteristics of ToCV isolates that favour infection of sweet pepper plants. [ABSTRACT FROM AUTHOR]

Plantain virus X was first recognized by the ICTV as a species in the genus Potexvirus in 1982. However, because no sequence was available for plantain virus X (PlVX), abolishing the species was proposed to the Flexiviridae working group of the ICTV in 2015. This initiated efforts to sequence the original isolates from Plantago lanceolata samples. Here we report the full‐genome sequencing of two original isolates of PlVX, which demonstrate that the virus is synonymous to Actinidia virus X, a species previously reported from kiwifruit (Actinidia sp.) and blackcurrant (Ribes nigrum). PlVX was previously noted to be widespread in the UK in P. lanceolata. This report additionally presents novel data on the distribution and diversity of PlVX, collected at the same site as the original UK isolates, and from three independent surveys, two in the Netherlands and one in Belgium. This study also includes two new host records for PlVX, Browallia americana and Capsicum annuum (sweet pepper), indicating the virus is more widespread and infects a broader range of hosts than previously reported. This stresses the importance of surveys of noncultivated species to gain insight into viral distribution and host range. This study also demonstrates the value of generating sequence data for isolates retained in virus collections. Additionally, it demonstrates the potential value in prepublication data sharing for giving context to virus detections such as the four independent studies here which, when combined, give greater clarity to the identity, diversity, distribution, and host range of plantain virus X. [ABSTRACT FROM AUTHOR]

Members of the Ralstonia solanacearum species complex (RSSC), causing potato bacterial wilt or brown rot, are highly contagious and there are no known cultivars with durable resistance to the pathogen. This study hypothesized (a) that crops intercropped or rotated with potato, plants in the same family, and plants grown in the neighbouring fields can host the pathogen and they can be potential sources of primary inoculum, and (b) that potato cultivars currently multiplied by the public tissue culture laboratory in Rwanda are less susceptible to the pathogen. Fourteen plant species and potato, and nine potato cultivars were tested for susceptibility to an RSSC phylotype II strain under greenhouse conditions. The bacteria induced symptoms on potato, tomato, tree tomato, sweet pepper, and eggplant only. Among the plant species with symptoms, potato, tomato, and tree tomato wilted completely. There was a significant difference in days to symptom expression and to complete wilting (p <.0001). While all tested potato cultivars were found to be susceptible, the number of days to first symptom expression, days to complete wilting, area under the disease progress curve (AUDPC), and the number and weight of harvested tubers varied considerably. Cultivars Cruza, Kinigi, and CIP‐58 were less susceptible whereas the cultivars Gikungu, Kirundo, and Victoria were highly susceptible. There is a strong need to search for other sources of resistance. The results indicate that some plant species that might serve as a reservoir of the bacterium should be avoided in the vicinity of potato crops. [ABSTRACT FROM AUTHOR]

Tomato spotted wilt virus (TSWV) has been present in Argentina since 1938 and had limited sweet pepper and tomato production until the introduction of resistant cultivars bearing Tsw and Sw‐5b genes. However, the wide use of TSWV‐resistant pepper plants in La Plata Horticultural Belt (LPHB) triggered the emergence of resistance‐breaking isolates (RB), increasing the economic impact of TSWV in pepper. This work characterized 11 natural RB pepper isolates from LPHB that have overcome the Tsw resistance gene in Capsicum sp. but are unable to break the Sw‐5b‐mediated resistance in tomato. Phylogenetic analysis of the N gene showed that the LPHB isolates are most closely related to isolates from Asia, indicating that Argentine TSWV isolates might have emerged from the Asian continent. The NSs sequence analysis reinforces the hypothesis that the appearance of an RB phenotype is a consequence of a number of different single amino acid substitutions spread along the NSs gene that lead to multiple independent evolutionary events. These results provide information on the current situation of the tospovirus–pepper/tomato pathosystems in LPHB, which represents a fundamental prerequisite to include these RB isolates in future screening programmes in order to select new and durable sources of resistance to TSWV in pepper. [ABSTRACT FROM AUTHOR]

In order to develop a method for discrimination of Corynespora cassiicola isolates pathogenic to sweet pepper among Japanese isolates, this study analysed pathogenic variations of 64 Japanese isolates of C. cassiicola on perilla, cucumber, tomato, aubergine and sweet pepper, and their multigene phylogeny. Japanese isolates were divided into seven pathogenicity groups (PG1-PG7). The virulence of isolates in PG1-PG5 was restricted to perilla, cucumber, tomato, aubergine and sweet pepper, respectively. Isolates in PG6 were virulent to sweet pepper, tomato and aubergine. Isolates in PG7 were avirulent to all tested plants. Multigene phylogenetic analysis of the isolates based on β-tubulin, translation elongation factor 1-α, calmodulin and actin genes showed three divergent clusters, MP-A, MP-B and MP-C. These clusters included all isolates in PG1, PG2, PG8 and PG9 (MP-A), PG3 and PG5 (MP-B) and PG4 and PG6 (MP-C). Isolates in PG7 were distributed amongst all clusters. Furthermore, random amplified polymorphic DNA (RAPD) analysis using universal primers, Q17 (5′-GAAGCCCTTG-3′) and Q13 (5′-GGAGTGGACA-3′), facilitated discrimination of isolates virulent on sweet pepper amongst isolates in MP-B and MP-C, respectively. Together, a combination of the multigene analysis and the RAPD technique allowed the discrimination of the isolates virulent to sweet pepper. [ABSTRACT FROM AUTHOR]

The effectiveness of hot water dipping on the control of grey mould, caused by Botrytis cinerea, and black mould, caused by Alternaria alternata on sweet red pepper quality was investigated. Dipping naturally infected or artificially inoculated fruit at 50°C for 3 min completely inhibited, or significantly reduced, decay development caused by B. cinerea and A. alternata, respectively. Heat damage was observed on fruit dipped for 5 min at 50°C, or at 55 C for 1 min or longer. Damage appeared as cracks and pitting on the fruit surface. Spore germination and germ tube elongation in vitro was inversely related to the duration of exposure or to the range of temperature used. The ET50 for spore germination for B. cinerea was 3.2, 1.5 and 0.8 min, and for A. alternata 8.8, 4.2 and 1.4 min, at 45, 50 and 55°C, respectively. The ET50 for germ tube elongation for Botrytis was 2.6, 0.9 and 0.5 min, and for Alternaria, 7.2, 2.5 and 1.6 min, at 45, 50 and 55°C The mode of action of hot water dips on decay of pepper appears to be by direct interaction with the fungi. [ABSTRACT FROM AUTHOR]

A new disease of peppers (Capsicum annuum) is described. The most characteristic symptom is vein yellowing of the youngest leaves. Some streaking occurs on the first-formed fruits. The symptoms were reproduced in pepper plants cv. Bellboy by graft and Olpidium transmission. Most pepper cultivars tested were susceptible but some appeared to be resistant. The disease had no effect on frail weight. [ABSTRACT FROM AUTHOR]

A stem and fruit rot of sweet peppers (Capsicum annuum) occurred in 1992 in West Sussex at affecting a large proportion of plants of cv. Tasty and to a lesser extent cv. Mazurka. Fuscirium solani was isolated from the stem lesions and also from a short distance above and below them The disease was largely modal. Distinctive fruit symptoms also occurred. Symptoms were reproduced by inoculation of wounds on the stem. On agar and in a small in vivo lest the pathogen was sensitive lo benomyl at 2 μg ml. The disinfectants, commercial sodium hypochlorite, Purogene and Tego 51 effectively killed macrospore-- following exposure for 15 min. [ABSTRACT FROM AUTHOR]

This article reports on the incidence of tobacco mosaic virus (TMV) infection of sweet peppers. Symptoms of TMV infection of sweet peppers are described. The results of these observations and experiments indicate that if peppers are grown on a tomato nursery great care must be taken to prevent TMV infection of the crop especially after planting out. Experiments also indicate that TMV from tomatoes readily infects peppers and that infection after the cotyledon leaf stage caused severe symptoms on some varieties. Of the varieties tested Yolo Wonder and Pine Tree showed some resistance.

The article examines the two new hosts associated with Candidatus Phytoplasma asteris in Cuba. It states that in a survey conducted in 2005, 12 percent of broad bean plants in a farm in Havana province showed symptoms of leaf yellowing, short internodes and stunting, and same symptoms were observed on sweet pepper plants growing in Holguin province in a rural farm. For further study, leaf samples of broad beans and sweet peppers were collected and undergone direct sequenced using primers P1/P7. The analysis showed the highest similarity to that of watercress yellows phytoplasma, an isolate of Candidatus Phytoplasma asteris. The study also confirmed that the report of a phytoplasma infection of broad bean and sweet pepper plants was the first in Cuba.

Examines the bacterial spot of tomato and sweet pepper in Tanzania. Importance of solanaceous cash crops; Assessment of the degree of contamination of seed; Pathogenicity tests of tomato.