Foliar‐spraying with wine pomace extract to alleviate freezing damage in some crops cultivated in northern Japan

BACKGROUND: Wine pomace, a byproduct of wine production, is problematic because of the environmental impact of its disposal. Extracts from wine pomace have been shown to exhibit anti-ice nucleation activity against bacterial ice nucleation caused by Erwinia ananas . OBJECTIVE: To investigate whether wine pomace extracts (WPEs) could be used as a frost protection agent for crops. MATERIALS AND METHODS: Wine pomace from the skins of grapes was extracted and used as WPEs. Adzuki, Chinese yam, and grapevine were selected as target crops to investigate freezing damage. Initially, the leaf discs of the three crops were used to determine droplet freezing temperature. We also investigated whether WPEs inhibited this damage. Second, the survival of whole adzuki seedlings exposed to low temperatures in the presence of E . ananas and WPEs was examined. RESULTS: In all crops, droplet freezing temperature increased in the presence of E . ananas , and this increase was suppressed following WPE treatment. Adzuki seedlings sprayed with WPE with E . ananas had higher survival rates than those sprayed with ultrapure water. CONCLUSION: This study showed that WPEs could prevent lethal damage to crops by reversing the increase in the freezing temperatures of droplets or crops caused by E . ananas .