Studies on a Nigerian isolate of banana streak badnavirus: I. Purification and enzyme linked immunosorbent assay

Abstract

SummaryA Nigerian isolate of banana streak badnavirus (BSV) was purified and a polyclonal antiserum was produced in mice. The antiserum titre was between 1 : 10 000 and 1:40 000 in enzyme-linked immunosorbent assay (ELISA), and showed a good specificity to BSV antigens. Comparative tests were carried out to determine the sensitivity and reliability of BSV antigen detection by double antibody sandwich (DAS)-ELISA, triple antibody sandwich (TAS)-ELISA, antigen coated plate (ACP)-ELISA, and protein-A coated antibody sandwich (PAS)-ELISA. TAS-ELISA using rabbit polyclonal antiserum to trap BSV and mouse polyclonal antiserum to detect the virus particles, was more sensitive than ACP-ELISA and PAS-ELISA and detected BSV in plant extracts from both symptomatic and some asymptomatic plants. However, immunosorbent electron microscopy detected more BSV-infected plants from asymptomatic plant samples than did TAS-ELISA. Results of this study showed that detection of BSV antigens in sap extracts by TAS-ELISA was most efficient with symptomatic tissues which occurred most frequently in the 'cool rainy' season. This suggests that for more reliable BSVindexing of field samples, tissue sampling should be done during the rainy season when most BSV-infected plants express severe symptoms.

Relationship between natural occurrence of banana streak badnavirus and symptom expression, relative concentration of viral antigen, and yield characteristics of some micropropagated Musa spp.

“…This, and the gross similarity between the symptoms caused by BSV and cucumber mosaic virus, makes symptom-based evaluation for BSV unreliable. Techniques have recently been developed for the serological detection of BSV in leaf tissues by ELISA (Thottappilly et al, 1998;, and this is the first report on the application of ELISA for evaluating Musa genotypes for resistance to BSV. In this study, more than 36 genotypes with diverse genetic backgrounds, including 14 registered TMPx hybrids, were evaluated for natural occurrence of BSV based on symptom expression, virus indexing, relative antigen concentration, bunch weight loss and components of the disease progress curve.…”

“…Some biological and molecular characteristics of an isolate (BSV-Onne) collected from this station have been described elsewhere (Harper et al, 1996;Dahal et al, 1998a;Dahal et al, 1999b;Thottappilly et al, 1998). Nigerian isolates of BSV are serologically distinct from several previously described BSV isolates (Lockhart & Olszewski, 1993) but they remain to be characterized.…”

“…Although many naturally occurring isolates of BSV are known to occur (B. E. L. Lockhart, unpublished data), to date isolates from Costa Rica, Honduras, Morocco, Rwanda and Trinidad have been recognized as serologically and genomically distinct (Lockhart, 1994;. Characteristics of a BSV isolate from southern Nigeria have been reported elsewhere (Dahal et al, 1998a;Thottappilly et al, 1998). The most common visual symptoms of BSV-infected plants include broken chlorotic streaks or spindle-shaped patterns on the lamina (Lockhart, 1986).…”

Rolling Circle Amplification Is More Sensitive than PCR and Serology-Based Methods in Detection of <i>Banana streak virus</i> in <i>Musa</i> Germplasm

“…The commonly used BSV-indexing tools include visual inspection for symptoms which are highly sporadic and may be confused with those of Cucumber mosaic virus (CMV), Immuno-Sorbent Electron Microscopy (ISEM), which is laborious and requires complex and expensive equipment, and Enzyme-Linked ImmunoSorbent Assay (ELISA) which has so far proved relatively insensitive [7]. The serological and genomic heterogeneity among BSV isolates has compounded the whole concept of BSV detection [8].…”

Development of Real-Time PCR for the Rapid Detection of Episomal Banana streak virus (BSV)

“…Current methods of detection of BSV include observation of symptoms, which are periodic and may be confused with those of other viruses; immunosorbent electron microscopy (ISEM), which is laborious and requires sophisticated material; enzyme-linked immunosorbent assay (ELISA), which is relatively insensitive (26); and immunocapture-polymerase chain reaction (IC-PCR), which requires pre-and post-PCR steps (4,8).…”