NoPv1, a new antifungal peptide able to protect grapevine from Plasmopara viticola infection

With the human population expected to reach 9.7 billion by the middle of this century, increasing agricultural productivity through the prevention of crop losses to pests and diseases has assumed considerable urgency. Modern agriculture strongly relies on pesticides to avoid losses and produce high-quality foods. Fungicides in particular represent the majority of plant protection products, with viticulture representing one of the first sector in terms of fungicide usage which has a serious negative impact on the environment and on human/animal health. As a consequence, crop protection is now oriented towards a rational use of pesticides and the development of eco-friendly pesticide alternatives. Among the available biotechnological solutions, peptide aptamers, i.e. artificial, high-affinity short peptides that specifically inhibit a target molecule through protein interference, are emerging as novel molecular tools. The oomycete Plasmopara viticola Berl. & De Toni is the causal agent of grapevine downy mildew, a worldwide destructive disease of primary importance for viticulture. Within the frame of GraptaResistance research project (https://sites.unimi.it/ graptaresistance/), funded by Fondazione Cariplo, we identified a novel peptide aptamer, named NoPv1 (No P. viticola 1), able to counteract P. viticola infection ex vivo (leaf disks) and in vivo (potted plants). NoPv1 has been isolated from a peptide library, through the yeast two-hybrid strategy, using the PvCesA2 protein (P. viticola cellulose synthase 2) as a bait. In addition, we demonstrated that NoPv1 targets specifically P. viticola as well as Phytophtora infestans, without affecting off-target organisms and being toxic for human cells