A classification of Pepper yellow mosaic virus isolates into pathotypes

Abstract

Pepper yellow mosaic virus (PepYMV) is the most important potyvirus infecting sweet pepper in Brazil. In this study, twenty isolates of PepYMV were obtained from commercial sweet pepper crops. To confirm virus identity, the coat protein gene was completely sequenced for eleven of these isolates, and partially sequenced for the other nine isolates. The amino acid identities obtained were above 93% when compared with the sequence of a characterized PepYMV isolate (AF348610). Extracts of Nicotiana tabacum cv. TNN plants infected with the different isolates were used to inoculate the differential series of Capsicum spp cultivars containing the genes pvr2 1 , pvr2 2 , pvr2 3 , pvr2 4 , and Pvr4. Using the same criteria established for Potato virus Y (PVY), fourteen isolates of PepYMV could be classified as known pathotypes described for PVY, that is: 1.2 (2 isolates), 1.3 (6) and 1.2.3 (6). The remaining six isolates, 1.3 (2) and 1.2.3 (4) could not be classified into the typical pathotypes of PVY because they were also virulent on Serrano Criollo de Morellos-334 (C.M 334) which carries the pvr2 3 and Pvr4 genes. To classify the PepYMV into pathotypes and counter the biological diversity found in this species we propose the utilization of 2 x for the ability to overcome the correspondent allele of the pvr2 locus and 4 for the capacity to break down the Pvr4 gene. Using this criterion we could classify the PepYMV into five

Inheritance of resistance to Pepper yellow mosaic virus in Capsicum baccatum var. pendulum

“…PepYMV prevails in the main sweet and chili pepper national-producing area and is considered, along with vascular wilt, a priority in Brazilian Capsicum breeding programs (Ávila et al, 2004;Maciel-Zambolim et al, 2004;Nascimento et al, 2007;Bento et al, 2009;Moura et al, 2011). PepYMV and PVY cause identical symptoms and these two viruses are serologically related, although they may be differentiated by some tests, such as indirect ELISA (Truta et al, 2004).…”

“…For example, the dominant allele Pvr4, identified in C. annuum cv. Criollo de Morelos 334, confers resistance to PVY, PepMoV, PTV, PepSMV, and PepYMV, often used in cultivars of sweet and chili peppers due to their wide activity (Janzac et al, 2009;Moura et al, 2011).…”

Solanum americanum: reservoir for Potato virus Y and Cucumber mosaic virus in sweet pepper crops

“…americanum plants showing mosaic symptoms and leaf distortion were found naturally occurring in sweet pepper crops in São Paulo State (Lins region, October 2011) and the presence of viruses was investigated (Figure 1). Double-antibody sandwich (DAS)-ELISA was carried out for the presence of potyvirus genus by utilizing antiserum anti-potyvirus (Agdia Inc., Elkhart, IN) (11). Two potyvirus positive samples (71d and 72d) were also analyzed by leaf dip, using Uranyl acetate (3%) as contrast solution, under an electron microscope (CM100 -Phillips), and 800nm filamentous particles, of potyvirus type, were observed for both samples.…”

“…To amplify the complete coat protein of PVY, the primer pairs PepNib (5' GWTSGYYGMMTTGGATGATG 3') and PepUTR (5' AGTAGTACAGGAAAAGCC 3') were used as described by (11) and the sequence was compared with those deposited in GenBank by using the programs Blastn (http://www. ncbi.nlm.nih.gov/BlAST) and Both CMV and PVY found in S. americanum are closely related to isolates collected from tomato (Figure 2 and 3), even though this isolate has been collected from sweet pepper crops.…”

Trypsin inhibitors from Capsicum baccatum var. pendulum leaves involved in Pepper yellow mosaic virus resistance

“…Among viral diseases, yellow mosaic, which is caused by the Pepper yellow mosaic virus (PepYMV, Potyvirus, Potyviridae), is considered to be the most important viral disease in pepper crops (Moura et al, 2011;Lucinda et al, 2012). Symptoms caused by the disease include reduced fruit and plant size, crinkled leaves, and a green-yellowish mosaic.…”