Location: Grape Genetics Research Unit (GGRU)Title: Assessment of freeze injury of grapevine green tissues in response to cultivars and a cryoprotectant product
|CENTINARI, MICHELA - Pennsylvania State University|
|SMITH, MARIA - Pennsylvania State University|
Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/12/2016
Publication Date: 7/15/2016
Citation: Centinari, M., Smith, M., Londo, J.P. 2016. Assessment of freeze injury of grapevine green tissues in response to cultivars and a cryoprotectant product. HortScience. 51(7):856-860.
Interpretive Summary: Crop losses that occur as a result of spring frosts threaten the economic sustainability of fruit crop producers all over the world. As climate patterns shift from year to year, frost risk varies. However, projections for continued changes in these patterns suggest that frost risk may be increasing. Farmers use a variety of methods to mitigate frost risk, including: choosing cultivars which have naturally delayed spring growth, large fans to circulate air, as well as using field based sprays of cryoprotectants to either prevent ice formation on plants or reduce damage of ice formation. In this study, tested the potential efficacy of one particular foliar fertilizer, KDL, for its ability to modify freezing damage on cuttings of cultivated grapevine. Dormant grapevine shoots for four cultivars, 'Albariño', 'Cabernet Franc', 'Cabernet Sauvignon', 'Pinot Grigio' were placed in a growth room to induce budbreak. The cuttings were sprayed with water, or KDL at 24 and 48 hours before being tested for freezing resistance using programmable freezers. Whole potted vines of a fifth cultivar 'Noiret' were also tested. Differences in freeze resistance were observed between cultivars with 'Albariño' being most sensitive. Results of KDL exposure were mixed, with some slight reduction in freeze damage noted for the 24 hour treatment, but not the 48 hour. The practical significance of KDL remains questionable; cultivar selection still appears to be a more reliable method for avoiding spring frost, by planting late bursting cultivars in frost prone areas.
Technical Abstract: Spring frosts and subsequent crop losses threaten the economic sustainability of fruit crop producers all over the world. This study used a controlled-freezing technique to impose a post-budbreak freezing stress to grapevine shoots forced from one-node cuttings ['Albariño', 'Cabernet Franc', 'Cabernet Sauvignon', 'Pinot Grigio' (Vitis vinifera)] and whole plants ['Noiret' (Vitis hybrid)]. Our goal was to investigate the incidence of freeze injury among cultivars, stage of phenological development, and a potassium salt-based fertilizer (KDL) with potential cryoprotectant activity. Among the V. vinifera cultivars, the incidence of mortality of shoots exposed to -3.5 °C was highest for 'Albariño' (71.7%) and lowest for 'Cabernet Sauvignon' (51.4%). Cuttings sprayed with KDL 24 hours before cold temperature exposure exhibited 16.1% lower shoot mortality and lower osmotic potential (-0.91 MPa) than the un-sprayed cuttings (-0.76MPa). However, application of KDL did not impact shoot mortality for whole 'Noiret' vines. Mortality for 'Noiret' shoots greatly increased with the advancement of phenological development, ranging from 11% in wooly buds to 77% in shoots about 10 cm long. The practical significance of KDL remains questionable; cultivar selection still appears to be a more reliable method for avoiding spring frost, by planting late bursting cultivars in frost prone areas.