Viruses are the main pathogens of hot peppers (Capsicum spp.) in Brazil, directly affecting yield and marketable fruit quality. Disease incidence related to natural infection by viruses was assessed ...in domesticated and semi-domesticated 'Malagueta' (Capsicum frutescens), 'Habanero' (Capsicum chinense) and 'Cumari' (Capsicum baccatum var. praetermissum) hot pepper accessions from Embrapa Vegetables Active Germplasm Bank, Brasília, Brazil. Seedlings were grown from treated seeds in the greenhouse and transferred to the field 30-45 days after sowing; trials were located in the vicinity of a naturally virus-infected pepper field. Sampling was performed after 60 days post transplanting when plants were 90-105 days old. A total of 482 plants was individually sampled, and tested for the presence of tospoviruses (Tomato spotted wilt virus - TSWV; Groundnut ringspot virus - GRSV; Tomato chlorotic spot virus - TCSV), potyviruses (Potato virus Y - PVY; Pepper yellow mosaic virus - PepYMV), and tobamovirus (Pepper mild mottle virus - PMMoV) by enzyme-linked immunosorbent assay (DAS-ELISA), and for cucumovirus (Cucumber mosaic virus - CMV) by dot-ELISA. Based on results of serological tests, 67% out of 482 plants presented single or mixed infections. The proportion of positive samples ranged from 9.1% (TCSV; 44 plants) to 45% (PMMoV; 217). PVY, PepYMV, TSWV and GRSV were found in 34.2% (165 samples), 25.5% (123), 15.7% (75) and 13.3% (64) of the tested-samples, respectively. CMV was not detected. It is noteworthy that virus infection was also detected on plants of the semi-domesticated genotype 'Cumari'. These results indicate the importance of viral diseases to crop management, considering the lack of efficient virus management strategies and the scarce information available on virus incidence affecting the crop, as well. A better understanding of the epidemiology of viruses infecting hot peppers will contribute to the development of rational disease management to prevent virus outbreaks.
In vitro regeneration from leaf, cotyledon and hypocotyl explants of six cultivars belonging to three species of Capsicum was achieved by direct organogenesis. The cultivar Umorok showed the best ...response while Meiteimorok, Haomorok, Mashingkha and Uchithi showed intermediate response and the cultivar Chiengpi was the least responsive. Leaf and cotyledon explants regenerated more shoots than hypocotyl explants and the maximum number of shoots were produced on Murashige and Skoog medium containing 8.8 microM 6-benzylaminopurine (BAP) with 11.4 microM indole-3-acetic acid (IAA). Elongation of shoot buds derived from different explants was achieved on medium containing 2.8 microM IAA and the elongated shoots were rooted on medium containing 2.8 or 5.7 microM IAA and 2.4 or 4.9 microM indole-3-butyric acid (IBA). Four-week old rooted plantlets were hardened and transplanted to the soil. The plantlets showed 90% survival during transplantation.
To induce somatic embryogenesis in habanero pepper (Capsicum chinense Jacq.), the cultivar BVll-03, belonging to the red type, was used. Different explants were evaluated, as were different culture ...media, the composition of which varied in the content of plant growth regulators. Results showed the formation of somatic embryos from cotyledons, zygotic embryos, germinated zygotic embryos, hypocotyls, and cotyledonary leaves. Explants were cultured on Murashige and Skoog medium supplemented with 2,4-D (9.05 micromolar). The somatic embryos always formed directly from the explant, without callus formation, and the greatest efficiency was obtained when segments of hypocotyls were cultured, obtaining 175 +/- 20 somatic embryos per explant. Only the somatic embryos obtained on Murashige and Skoog medium containing 2,4-D (9.05 micromolar) and treated with abscisic acid (ABA) (1.89 micromolar) before their transfer to the germination media (Murashige and Skoog + 1.1 micromolar GA3) emitted their radicule and expanded their cotyledonary leaves (60%), whereas the remaining embryos did not achieve germination because of different causes (abnormalities, delayed development). Not only is this protocol of somatic embryogenesis the first to be reported for this species (C. chinense Jacq.), but it is also the most efficient reported so far, within the Capsicum genus.
To induce the somatic embryogenesis of Habanero pepper, different culture media and different types of explants (node, internode, hypocotyl, half seeds, and fruit segments) were evaluated. For the ...induction of embryogenic callus, 9.05 μM of 2,4-dichlorofenoxiacetic acid, 3% sucrose, and 0.8% gelrite were added to the basic MS medium over a period of 30 days at 25 ± 2 °C under continuous light (40-50 micromol·m2·s-1). Once the callus formed, they were transferred to liquid medium using the same induction formulation. Somatic embryogenesis only occurred from explants of hypocotyl and in the presence of 3.4 μM thidiazuron. This constitutes the first proposal of a protocol for the "induction of somatic embryogenesis in Habanero pepper (Capsicum chinense Jacq.) from cell suspensions."
Habanero chili pepper (Capsicum chinense) is widely consumed as a fresh vegetable, although its extremely high capsaicin content has led to other uses (e.g., medicine and self-defense). Recently ...described antimicrobial peptides from C. annuum were very efficient in inhibiting growth in human and plant pathogenic bacteria and fungi. In order to explore the potential use of Capsicum chinense seeds as a source of antimicrobial peptides, in the present study a peptide fraction from C. chinense pepper seeds, denominated G10P1, was enriched, partially purified and its antimicrobial activity tested against the plant and human pathogens Xanthomonas campestris, Pseudomonas syringae, Pseudomonas aeruginosa, Erwinia carotovora, Agrobacterium sp., Shigella flexnerii, Escherichia coli, Staphyllococcus aureus and Bacillus subtilis. The minimum inhibitory concentration of the G10P1 peptide fraction against X. campestris was 12.5 kg mL super(-1). Electrophoresis of the G10P1 in a denaturant 15% polyacrylamide gel showed it to be composed of 67.57 and 65.6 kDa polypeptides, both associated with an area of strong antibacterial activity. The sequencing of 18 amino acids from the N-terminal of the 67.57 peptides and 12 from the 65.6 kDa peptides showed no clear association with previously described antimicrobial peptides. However, the 65.6 kDa peptides were related to the NAC and WRKY transcription factors, both involved in direct regulation of the plant defense response against pathogen attack and the 67.57 kDa peptides had low homology with a 3-oxo-acyl-carrier-protein synthase from Capsicum chinense.
Yellow lantern chilli (Capsicum chinense (Jacq.), the world's hottest chilli is mostly grown in the north eastern part of India. The crop is cultivated by traditional ways since time immemorial. ...However, very little research towards scientific cultivation has been conducted in the past and until now scientific package of practices is not available. In the present investigation, the effect of various planting time and spacing on the growth characteristics of the hottest chilli, yellow rantern chilli (bhoot jolokia) was studied in north-eastern hill region of India. Seeds of the variety local cultivar, bor Bhoot of bhoot jolokia were planted in four different dates i e September 15 (P1), October 15 (P2), January 15 (P3) and February 15 (P4) with three spacings viz. 75cm × 75cm (S1), 90cm × 90cm (S2) and 105cm × 105cm (S3). The results revealed that the growth parameters and yield attributing characters were significantly influenced by different planting dates and spacings. Sowing in September 15 (P1) and with a spacing 105cm × 105cm (S3) were recorded the highest plant height, number of primary branches, number of fruits/plant, fruit weight and fruit yield/plant. In case of phyllochron index September 15 sowing showed maximum days to phyllochron but closest spacing 75cm × 75cm showed maximum phyllochron. Among all the treatments, the crop sown in September with a spacing of 105cm × 105cm showed better performance for all the parameters studied and can be considered basis for studying the effects of other agronomic practices.
The dominant gene Pvr7 from Capsicum chinense Jacq. 'PI159236' confers resistance to the pepper mottle potyvirus (PepMoV) Florida (V1182) strain. This gene is tightly linked to the dominant potyvirus ...resistance gene Pvr4 with observed recombination frequencies of 0.012 to 0.016. A cleaved amplified polymorphic sequence (CAPS) marker linked to Pvr4 was used to localize Pvr4 and, by extension, Pvr7, to linkage group 10 on an interspecific map of pepper. Our results indicated that Pvr4, Pvr7, and Tsw, a gene conferring resistance to tomato spotted wilt virus, comprise the first identified cluster of dominant disease resistance genes in Capsicum L. This position does not correspond to the locations of dominant potyvirus resistance genes in potato or to the positions of any other mapped solanaceous resistance genes or resistance gene homologues.PUBLICATION ABSTRACT
Scirtothrips dorsalis (Hood) (Thysanoptera: Thripidae) is a recently identified invasive pest to the Caribbean and poses a significant threat to agriculture and trade in the region. Methods are ...needed to detect the presence and to monitor populations of this pest so that it can be effectively managed. Three different CC trap base colors (blue, yellow, and white) with or without dichlorvos as a killing agent, and a newly developed and named the Blue-D trap were studied in Taiwan and St. Vincent for attraction and capture of S. dorsalis. In lemons in Taiwan, mean numbers of S. dorsalis caught in Blue-D traps were greater compared with dichlorvos cube modified CC traps. In St. Vincent chili pepper plantings, the Blue-D traps caught more Thrips palmi (Karny), Frankliniella sp., and Microcephalothrips abdominalis (Crawford) than dichlorvos cube modified CC traps. More Frankliniella intonsa (Trybom), Megalurothrips usitatus (Bagnall), T. palmi, Frankliniella sp., and M. abdominalis were caught in blue and white base CC traps than yellow base CC traps. Average captures per CC trap per week were 0.07 and 0.02-0.09 S. dorsalis in Taiwan and St. Vincent, respectively. There were no differences in S. dorsalis captures in white, blue, or yellow base CC traps. The average weekly S. dorsalis catch for yellow sticky card traps was 19.8. CC traps can be used for detection of S. dorsali and collecting intact S. dorsalis for taxonomic and genetic determinations when a few of the species are found in a large commercial production area. Yellow sticky traps can be used for monitoring S. dorsalis populations. A combination detecting system of visual observation, yellow sticky traps, and CC traps may be an effective S. dorsalis population detecting and monitoring system.
The molecular and biological characterization of a begomovirus infecting the common weed Macroptilium lathyroides from Jamaica are reported. The virus showed 92% sequence identity to an isolate of ...Macroptilium yellow mosaic virus (MaYMV) from Cuba, but was distinct from the two other begomoviruses isolated from M. lathyroides, namely Macroptilium yellow mosaic Florida virus (80% identity) and Macroptilium mosaic Puerto Rico virus (68% identity). Hence, the Jamaican begomovirus was considered an isolate of MaYMV and called Macroptilium yellow mosaic virus-Jamaica (MaYMV-JM). In infectivity studies using cloned DNA-A and DNA-B genomic components, MaYMV-JM infected red kidney bean (Phaseolus vulgaris) and produced mild symptoms in Scotch Bonnet pepper (Capsicum chinense), but did not infect cabbage (Brassica oleracea). This information has implications for the development of strategies to control begomovirus diseases in Jamaica and elsewhere.
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