Page 52 - Grapevine March-April 2020

Around The Vineyard

be seen when there is a change of color in the wells
Fairhaven Vine Nursery of the test plate (colorimetric enzymatic reaction).

The Science of Sustainable Viticulture ELISA detection is limited to the amount of virus
present in the sample. PCR, is the abbreviation for
polymerase chain reaction. The technique allows
Container Grown the multiplication of viral nucleic acid from the ini-
Vines Plantable tial titer (concentration) of pathogen present in the
Year Round vine. The process is specific, and utilizes copies of
Specialist In... small portions of the pathogen’s genome to start
• Adaptive Varieties the copying process. The amplification is repeated
• Certified Vinifera many times, with each copy making more copies,
• American Hybrids so after the completion of an appropriate number
• French American Hybrids of PCR cycles, more than a billion copies of the
We Also Offer... nucleic acid is produced. For RNA viruses the detec-
• Trellis Equipment tion is done using RT-PCR (RT = a copy of the viral
RNA via reverse transcription) before PCR can start.
• Planting Supplies PCR and RT-PCR are sensitive techniques used for
• Drip Irrigation Design the detection of grapevine pathogens.
& Supplies
• Advanced Specialty The sensitivity and specificity of the detection
Fertilizers
of pathogens can be influenced by the season as
903-279-7477 well as the part of the vine from which samples

info@fairhavenvineyards.com are collected. While ELISA is generally thought
to be less sensitive than RT-PCR, the ELISA has a
www.fairhavenvinenursery.com broader spectrum of detection but is available only
™ TX State Lic# 6034-2259
for grapevine viruses and can detect a range of
virus variants. On the other hand, PCR can be too
Dry Material Spreaders specific, and miss the detection of isolates of the

same virus even when slightly different. Using both
ELISA and RT-PCR consecutively is recommended
to reliably detect grapevine leafroll viruses, as each
method is designed to detect different portions of
a virus.

Single Use Strips for “in house” Detection
Custom Sizes & Shapes
Are Our Specialty! A molecular single use strip test has been devel-
oped for the detection of Grapevine red botch
virus (GRBV) that can be used for in-field testing.
S&A Manufacturing offers a full line of Although, this test is marketed for use in the field,
fertilizer handling & spreading equipment for reliable results, the assays should be conducted
including portable or fixed Conveyors, by experienced technicians in a clean laboratory.
If a lay person were to attempt to run the assay,
Storage Containers, Bulk Bins & Tanks. they the instructions must be carefully followed, as
To see our full line visit our website! the steps are complicated and require measuring
www.samfg.com small quantities of material (microliters of com-
ponents). In my opinion, it is worthwhile to have
S&A Manufacturing an experienced laboratory run these tests. It is

7211 N. Pacific Ave. • Livingston, CA 95334 expected that laboratory personnel are trained to
keep the sample and other materials free of con-
Phone: 209-394-8048 • Fax: 209-394-4522 tamination. In the past, a kit was available for the

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