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div>The vulnerability of Chardonnay stems measured by the various techniques ranged from a ��50 (i.e. ��x at 50% loss of conductivity) of ?0.21?MPa for the short segment air injection to ?2.97?MPa for the dehydration technique on field-grown plants (Fig.?3, Table?1). All methods were compared with each other at three levels of ��x: ?0.5, ?2.0 and ?3.5?MPa (Table?2). There was no significant difference between dehydration vulnerability curves conducted on field-grown or greenhouse-grown Chardonnay at any value of ��x tested (P?>?0.05; Table?2). The dehydration technique was also assessed on short segments (i.e. segment lengths equal to those used in the centrifuge technique) and did not differ significantly than dehydration on longer segments from the field and greenhouse (Fig.?3; hollow diamonds). The Torin 1 concentration long segment air-injection technique agreed with the dehydration technique (P?>?0.05; Selleckchem Regorafenib Fig.?3, Tables?1 & 2) with low PLC at ��x?>??2.0?MPa. Conversely, stems subjected to the short air injection technique exhibited extremely high vulnerability to cavitation reaching ?100 PLC by ��x?=??0.5?MPa. Flushed stems from the centrifuge technique also exhibited high vulnerability to cavitation across all three levels of ��x compared with those from the dehydration and long-segment air injection techniques (P?<?0.05; Table?2). Stems from the flushed centrifuge and short-segment air injection techniques had the only ��50s?>??2?MPa (Table?1) and had the steepest slopes, meaning conductivity was lost across a more narrow range of water potentials than by the other techniques as ��x decreased (Fig.?3, Table?1). Interestingly, vulnerability to cavitation measured with the native sap centrifuge technique was similar to the flushed centrifuge technique at low tensions (i.e. ��x?��??0.5?MPa), was different than all other techniques at ��x?=?1.0?MPa, and was similar to dehydration and long-segment air injection techniques at high tensions (i.e. ��x?��??2.0?MPa) (Fig.?3, Tables?1 & 2). NMR imaging revealed that the number of cavitated vessels was relatively low at ��x?>??2.0?MPa (Fig?4a,b). The number of large cavitated vessels increased sharply at around ?2.0?MPa, similar to the VCs generated by dehydration and air-injection but differing from Floctafenine centrifuge curves (Figs?4c,d & 5). NMR image analysis showed that the percentage of empty vessels observed in the cross section increased as a function of decreasing ��x in a similar manner to the increase observed for PLC in bench top dehydration VCs (Fig.?5). After completion of the NMR for each vine, stem PLC was measured and revealed values similar to those measured by the dehydration and air-injection techniques (Fig.?5). PLC was <17% in all samples with a ��x higher than ?1.6?MPa (Fig.?5). Our results indicate the flushed centrifuge and short segment air-injection techniques overestimate vulnerability to water stress-induced embolism in V. vinifera across all ��x.