Comparison of RNA extracts from in vitro shoot tip cultures of leafroll-affected and leafroll-free grapevine cultivars

The RNA content of in vitro shoot tip cultures from grapevine leafroll (GLR) disease-affected grapevines was analyzed and compared to that of similar cultures from GLR-free grapevines. A previously unreported low-molecular-weight single-stranded RNA (LMWssRNA) was detected in in vitro shoot tip cultures of 65 % (11 out of 17) of GLR-affected cultivars. This LMWssRNA was absent from disease-free cultivars and may be associated with a virus or a strain of a virus responsible for GLR. Numerous high-molecular-weight (HMW) dsRNA bands were also detected in GLR-affected grapevine cultivars. The intensities and mobilities (apparent molecular weights) of these dsRNA bands varied considerably from one GLR-affected cultivar to the next, but were reproducible for each cultivar. The detection of multiple distinctive RNA banding patterns is consistent with the possibility that more than one agent can cause grapevine leafroll disease

Double-stranded RNA from rupestris stem pitting-affected grapevines

Nucleic acids were extracted from in vitro shoot tip cultures of 31 grapevine cultivars affected with rupestris stem pitting (RSP) disease and from cultures of 11 RSPfree cultivars, 4 of which were disease-free, 2 of which were fleck-affected and 5 of which were grapevine leafroll disease-affected. Analysis of the extracts by polyacrylamide slab gel electrophoresis showed that 21 of the 31 RSP-affected cultivars contained a previously unreported nucleic acid which was absent from the RSP-free controls. Nuclease digestions showed that the nucleic acid was double-stranded RNA (dsRNA). The apparent size of the dsRNA was inconsistent with that expected for either a viroid or a closterovirus. The observation that 10 of the 31 RSP-affected cultivars lacked this dsRNA is consistent with the view that there may be more than one 'RSP-like' disease. The dsRNA detected in this investigation may be associated with one of these diseases

Mechanical sap transmission of a closterovirus from in vitro shoot tip cultures of a leafroll-affected grapevine to Nicotiana benthamiana

Transmission manuelle d'un clostérovirus au Nicotiana benthamiana à partir de cultures in vitro d'une vigne atteinte de l'enroulementDes cultures in vitro d'une vigne de Vitis vinifera Limberger atteinte de l'enroulement ont été broyées dans une solution tampon contenant de la nicotine. Les extraits ont été inoculés sur des feuilles de Nicotiana benthamiana et de 6 autres espèces de plantes herbacées. 3 semaines plus tard, seuls les plants de N. benthamiana ont démontré des symptômes. Ceux-ci consistaient d'un nanissement systémique accompagné d'un éclaircissement des nervures qui se transformait en chlorose interveinale. Les feuilles de ces N. benthamiana contenaient le virus A de la vigne (GVA), démontré par la méthode ISEM

Broadening the model of science - Recognizing different types of contributions

Resources for Society for the Improvement of Psychological Science (2016) Meeting - Diversity & Alternative Contribution