Avoiding frost damage in grapevines by application of various protective substances

Abstract Damage to viticulture caused by late frost is one of the most serious threats to this production sector. There are numerous approaches for mitigating the effects of late frost. Most of the methods are prophylactic or require specific technical equipment. One simple option is to lower the freezing point and thus prevent damage to plant cells. In this study, a wide variety of substances were examined for their protective potential. By using a frost chamber, temperature profiles were applied corresponding to a natural frost night. Over 20 different substances were evaluated on vine cuttings which were exposed to frost after a reaction time. Most substances did not result in any improvement in frost stability. Only with the double application of urea, Cropaid, Natriumhydrogencarbonat, Superfifty and Zn Chelate a higher survival rate was observed after frost chamber treatment. In addition, outdoor tests confirmed the protective potential of urea application. An additional field trial demonstrated significant frost protection following the application of Megafol solution to grapevine shoots at approximately BBCH stage 14. However, no significant differences in yield were observed at harvest.