Morfologia e aspectos intracelulares do vírus latente da couve

Abstract

SINOPSEPartículas alongadas de 15 mu de diâmetro e 650 mu de comprimento normal foram consistentemente detectadas em exames electrono--microscópicos de preparações "leaf dip" de 6 espécies diferentes de plantas infetadas pelo vírus latente da couve (Brassica oleracea L. var. acephala) (VLC). Tais partículas são consideradas como sendo de um vírus que poderia ser incluído no grupo do vírus S da batata, na classificação dos vírus alongados de Brandes.Exames de secções ultrafinas de tecidos foliar e radicular de couve infetada pelo VLC, demonstraram a ocorrência do VLC, formando agregados mais ou menos organizados no citoplasma. Não se notou alterações citológicas sensíveis como conseqüência da infecção, o que está de acordo com a ausência de sintomas externos em couve infetada pelo VLC. -INTRODUÇÃODurante investigações sobre a suscetibilidade de variedades de couve (Brassica oleracea L. var. acephala) ao vírus do mosaico do nabo (= vírus da mancha anular preta do repolho), verificou-se que todas as variedades em estudo estavam infetadas por um vírus latente. Este vírus, denominado de latente da couve (VLC), é transmissível mecanicamente e por afídeos a várias plantas testes (Costa, dados não publicados).

Light and electron microscopy of red clover vein mosaic virus in pea (Pisum sativum)

“…Our results show that RCVMV has an intracellular distribution comparable to that of other members of the carlavirus group studied so far: potato virus M (Tu and Hiruki, 1970), potato virus S (de Bokx and Waterreus, 1971), P a s s i f t o r a latent virus (Bos and Rubio-Huertos, 1971), carnation latent virus (Castro et al, 1971), pea streak virus (Bos and Rubio-Huertos, 1972), and the recently reported cole latent virus (Kitajima et al, 1970) apparently also belonging to the group. With none of these viruses has true crystallization been observed, perhaps because their particles are not sufficiently straight although rather rigid.…”

Coat protein and RNAs of Cole latent virus are not present within chloroplasts of Chenopodium quinoa-infected cells

“…The cytopathology caused by CoLV in local lesions induced in C. quinoa was shown to be very similar to that induced by the same virus in systemically infected cole (Kitajima et al, 1970) and by other members of the Carlavirus genus (Tu & Hiruki, 1970;Brunt et al, 1976;Hearon, 1982;Koenig, 1982, Thongmeearkon et al, 1984Weintraub, 1993;Rudzinska-Langwald, 1990). The CoLV can be seen in cytoplasm as scattered particles interspersed with membranous vesicles and ribosomes ( Figure 1A) a common feature found in cells infected by many plant viruses and considered to be the site of virus multiplication (Martelli & Russo, 1977).…”

“…acephala) in the State of São Paulo, Brazil (A. S. Costa, unpublished results). Based on its pathological and morphological characteristics (filamentous particles c. 650 nm in length), CoLV was considered to be a member of the genus Carlavirus (Kitajima et al, 1970;Brunt et al, 2000).…”

“…Thin sections of cole root and leaf infected by CoLV, showed the occurrence of particle aggregates and vesiculated areas in the cytoplasm in most of the cells, except within the tracheids and sieve tubes (Kitajima et al, 1970). *Part of the Dr. thesis of the first author.…”

Evidence Supporting the Recognition of Cole latent virus as a Distinct Carlavirus

“…acephala in São Paulo State, Brazil (A. S. Costa, unpublished results). Based on its pathological and morphological characteristics (filamentous particles 650 nm in length), CoLV was considered to be a carlavirus (Kitajima et al., 1970). The virus is transmitted mechanically and also inefficiently in a non‐persistent manner by Myzus persicae (Mello, 1981).…”