Potato spindle tuber viroid eradicated in Western Australia
Potato spindle tuber viroid (PSTVd) was detected for the f irst time in an isolated hydroponic greenhouse tomato (Lycopersicon esculenturn) erop in the great southern region of Western Australia (WA). An urgent eradication plan was activated because of the highly contagious nature of the pathogen. The tomato erop on the infected property was destroyed and the greenhouses and surrounding area were decontaminated. Surveys of 15 other hydroponic tomato crops did not detect any other PSTVd infected tomato plants in WA.
Detection of Plum poxpotyvirus in illegally imported plums intercepted at Sydney International Airport
Plum pox potyvirus (PPV) was detected in an illegal consignment of plum budwood and fruit intercepted by Australian Quarantine and Inspection Service (AQIS) inspectors at Sydney International Airport. PPV was detected in leaf, bark and peduncle tissue using enzyme linke d immunosorbent assay (ELISA), re verse transcription-polymerase chain reaction (RT-PCR) and electron microscopy. The strain of PPV detected was the D strain as indicated by ELISA and restriction enzyme analysis of the P1-P2 243 bp PCR product.
Instrumentation and Automated Photometric Titration Procedure for Total Acidity Determination in Red Wine Employing a Multicommuted Flow System
An automated procedure for photometric titration of red wine and associated instrumentation is described. The procedure was based on the flow-batch approach implemented employing multicommutation. The photometric detection was carried out using a homemade LED-based photometer. The mixing device, LED, and photodetector were attached to the titration chamber in order to form a compact and small-sized unit. The flow system comprised an automatic injector and three-way solenoid valves, which were controlled by a microcomputer through an electronic interface card. The software, written in Quick BASIC 4.5, was designed with abilities to accomplish all steps of the titration procedure including data acquisition and real-time processing to decide about the course of titration in the following step and so forth, until the titration endpoint was reached. The usefulness of the proposed titration system was demonstrated by analyzing red wine samples. When results were compared with those obtained using the AOAC reference method, no significant difference was observed at the 95% confidence level. A relative standard deviation of ca  2% (n=9 ) was obtained when processing a typical red wine sample containing 7.3 gl -1 total acidity expressed as tartaric acid.