Advances in understanding grapevine downy mildew: From pathogen infection to disease management

Abstract

Plasmopara viticola is geographically widespread in grapevine‐growing regions. Grapevine downy mildew disease, caused by this biotrophic pathogen, leads to considerable yield losses in viticulture annually. Because of the great significance of grapevine production and wine quality, research on this disease has been widely performed since its emergence in the 19th century. Here, we review and discuss recent understanding of this pathogen from multiple aspects, including its infection cycle, disease symptoms, genome decoding, effector biology, and management and control strategies. We highlight the identification and characterization of effector proteins with their biological roles in host–pathogen interaction, with a focus on sustainable control methods against P. viticola, especially the use of biocontrol agents and environmentally friendly compounds.

In Vitro Collection for the Safe Storage of Grapevine Hybrids and Identification of the Presence of Plasmopara viticola Resistance Genes

“…Grapevines are highly susceptible to fungal infections, and P. viticola has long been a threat to grape production worldwide, especially in areas with relatively warm and humid climate conditions [ 26 , 96 , 97 , 98 ]. Considerable efforts have been made internationally to identify genetic resources for resistance to P. viticola [ 42 , 96 , 99 , 100 , 101 , 102 , 103 , 104 ].…”

“…Grapevines are highly susceptible to fungal infections, and P. viticola has long been a threat to grape production worldwide, especially in areas with relatively warm and humid climate conditions [ 26 , 96 , 97 , 98 ]. Considerable efforts have been made internationally to identify genetic resources for resistance to P. viticola [ 42 , 96 , 99 , 100 , 101 , 102 , 103 , 104 ]. The development of grapevines with such a level of resistance to this threat is a highly desirable and sustainable strategy to overcome this problem [ 26 ], and it would also contribute to reducing the massive use of pesticides in orchards.…”

Traditional and Emerging Approaches for Disease Management of Plasmopara viticola, Causal Agent of Downy Mildew of Grape

“…Copper does not degrade in soil but accumulates, resulting in potential water and soil contamination that can be harmful to organisms [53,54]. As a result, the European Union has restricted the application of cupric fungicides (Regulation 473/2002) [53,55]. The microencapsulation of copper may offer a means of reducing the amount of copper applied per spray by up to 50% [53].…”

“…Many of these had multi-site activity that reduced the risk of resistance development [57]. These included captan (dithiocarbamates), methiram, maneb, mancozeb, propineb, captafol, folpet, and dichlofluanid [7,55]. The disadvantages of contact fungicides are that they sit on the waxy surface of the leaf, are subject to wash-off by rainfall, and only protect vines from future infections.…”

“…Fungicides that could penetrate the leaf's surface, allowing them to attack existing infections as well as provide lasting protection that could extend to new growth, occurred with the development of systemic fungicides in the 1970s and beyond. These systemic fungicides could not be washed off once inside the plant and displayed significant curative effects [7,55]. Some systemic fungicides could migrate within the plant to protect new shoots and leaves up to one-to-two weeks post-application [7,58,59].…”