This study was conducted to determine the incidence, diversity and distribution of viruses infecting pepper (Capsicum spp.) in the central, northern and northeastern parts of Thailand. During a survey in 2016 - 2019, a total of 2,149 leaf samples from symptomatic and asymptomatic peppers were collected randomly from farmer's fields, and preliminary tested by an enzyme-linked immunosorbent assay (ELISA) using 7 antibodies specific for cucumber mosaic virus (CMV), chilli veinal mottle virus (ChiVMV), tomato necrotic ringspot virus (TNRV), tobacco mosaic virus (TMV), potato virus Y (PVY), tomato spotted wilt virus (TSWV), and begomoviruses. Our data revealed that the incidence of the viruses infecting pepper in Thailand was high, accounting for nearly 70% (1,482 infected samples). The highest viral incidence was found in the central part (96%), followed by the north (74.4%) and the northeastern (52.8%), respectively. Begomoviruses, CMV, ChiVMV, and TNRV were detected in the samples at varying rates, whereas PVY, TMV, and TSWV were not detected. Of these, the most frequently found virus was Begomoviruses accounting for nearly 33%, with the highest rate (ca. 82%) in the central Provinces of Thailand. In addition, of the 1,482 infected samples, mixed infections among the four viruses were also found in 616 samples (ca. 42%), and CMV + ChiVMV (approximately 11%) was the most common mixed infection. This is the first report describing an occurrence of viruses in pepper of Thailand, and the results obtained have revealed that viruses infecting pepper are widespread, which may pose a threat to pepper production in Thailand.

Incidence of viruses infecting pepper in Thailand

/pdf/correlation-between-symptoms-and-elisa-for-the-detection-of-9t4rea16kw.pdf

Correlation between Symptoms and ELISA for the Detection of Cucumber Mosaic Virus in Bell Pepper

Tomato and pepper are important vegetable crops grown in Nigeria, accounting for 50% of the African production. Pathogen diversity is a prerequisite for breeding resistant cultivars, as a means of improving the production. A survey for virus disease incidence on field grown pepper and tomato was carried out in three state of southwestern part of Nigeria, and a total of 135 leaf samples comprising 58 tomato and 77 pepper leaf samples were collected from farmers’ fields. Infecting viruses were detected using specific polyclonal antibodies were used in enzyme-linked immunosorbent assay (ELISA). Four viruses, Potato virus Y (PVY), Tomato mosaic virus (ToMV), Cucumber mosaic virus (CMV), and Pepper veinal mottle virus (PVMV) were detected. In tomato the distribution of viruses was 5.2% (CMV), 5.2% (PVY) and 39.7% for PVMV, respectively. Leaf samples of pepper had incidence rate of 19.5%, 3.9% and 67.5% for CMV, ToMV and PVMV respectively. TSWV and TYLCV were not detected in any of the samples tested. The most prevalent virus on tomato and pepper was PVMV which was also the most prevalent virus in Osun, Ogun and Oyo States in Southwest Nigeria; similarly, CMV was detected in pepper crops in all the states surveyed and the most prevalent after PVMV in the three states. Mixed viral infections were few, PVY + PVMV occurring only in one tomato leaf sample while PVMV + CMV occurred on three pepper leaf samples. The control of aphid vectors that transmit these viruses and good sanitary practices against soil borne ToMV would minimize disease incidences and subsequent yield loss. Keywords : Tomato, Pepper, virus distribution, PVMV, CMV, PVY

/pdf/serological-detection-of-viruses-infecting-tomato-and-pepper-47tlhlcp9d.pdf

Serological detection of viruses infecting tomato and pepper in Southwest Nigeria and their distribution

The present study was conducted to evaluate an eco-friendly crop protection system having less reliance on pesticides with an existing crop protection system adopted by farmers depending on frequent use of pesticides for management of whitefly-transmitted virus diseases of chilli. Further, quantification of defense-related enzymes in chilli leaf tissues and calculation of field use environmental impact quotient of pesticide use were done for the crop grown under the two systems. Field experiments were conducted at five locations, namely Kilinochchi, Mahailluppallama, Kundasale, Peradeniya and Rahangala using chilli cv. MI Green for two consecutive growth seasons to evaluate the two crop protection systems. Percentage incidence of chilli plants showing virus-like symptoms varied significantly by location, growth stage and the interaction effect between location x crop protection system in both seasons. Chilli leaf curl complex infestation and leaf deformation were the most prominent in the chilli plants showing virus-like symptoms. In general, there was no significant variation (P = 0.05) between the two crop protection systems on the activity of four defense enzymes tested (i.e. peroxidase, β-1,3-glucanase, chitinase and phenylalanine ammonia lyase) in chilli tissues. The eco-friendly system had lower environmental impact of pesticides compared to the existing crop protection system practiced by farmers in chilli fields. Multi-location trials for two growing seasons confirmed that the eco-friendly package tested is equally-capable as the existing crop protection system for the management of virus diseases in chilli in Sri Lanka with a lower environmental impact.

Evaluation of the effects of an eco-friendly crop protection system on management of whitefly-vectored chilli leaf curl virus disease in Sri Lanka

Surveys conducted in capsicum growing localities of Solan district in Himachal Pradesh revealed a high incidence of cucumber mosaic virus. Mottling, mosaic, mid vein distortion, puckering and leaf deformation were the striking symptoms observed on the leaves of capsicum. Due to the complexities of symptoms, appearance of visual symptoms alone is not sufficient enough to establish the identity of the causal virus. Leaves from symptomatic plants were collected and serologically detected through ELISA. A total of 70 capsicum varieties/breeding lines were evaluated for their reaction to CMV, out of which 14 were found to be resistant based on their optical density values. ELISA was observed to be a quick and reliable method for indexing germplasm on a large scale.

https://www.chemijournal.com/archives/2020/vol8issue6/PartB/8-5-262-327.pdf

Evaluating cucumber mosaic virus in capsicum germplasm using ELISA

Pepper (Capsicum annuum L.) as one of the main crops in Dezful, Iran is treated by several viruses. In this survey for detection of viruses, around 500 leaf samples of sweet pepper plants from 23 fields of Dezful with symptoms including mosaic, mottle, crinkling and dark green vein banding, deformation and stunting were collected during 2012 and 2013 growing seasons. Collected samples were analyzed by DAS-ELISA using several polyclonal antibodies. Results showed 55, 23, 17, 15, 21, 18 and 13 samples were only infected with Pepper veinal mottle virus (PVMV), Pepper mild mottle virus (PMMV), Pepper mottle virus (PMV), Potato virus Y (PVY), Alfalfa mosaic virus (AMV), Cucumber mosaic virus (CMV) and Tomato spotted wilt virus (TSWV), respectively. Several samples were infected by more than one of aforementioned viruses. The incidence of infections with two was seen in 28.8% , with three viruses in 9.6% of collected samples. Multiple infection was detected in 8.6%of samples. The high incidence of PVMV revealed that this virus is the dominant constraint to cultivation of pepper crops in Dezful. To our knowledge this is the first report of pepper veinal mottle virus, Pepper mild mottle virus, Pepper mottle virus and Tomato spotted wilt virus in pepper fields of Iran.

http://www.bepls.com/bepls2014march/20.pdf

Parisa Soleimani

Papers

Distribution of some viral disease on pepper (Capsicum annum) plants in Dezful fields from Iran