The Distribution of Phytoplasmas in South and East Asia: An Emerging Threat to Grapevine Cultivation

Abstract

Grapevine is largely cultivated in several parts of the world, and a spurt in its cultivation has occurred in the last two decades in grapevine cultivated areas of South and East Asia, mainly in China, India, Japan, Korea, Thailand, and Indonesia. Grapevine yellows (GY) represent one of the most important diseases in viticultural areas of the world, and they have been assigned to five different groups: aster yellows [AY (16SrI)], peanut witches’ broom [PnWB (16SrII)], X-disease (16SrIII), elm yellows [EY (16SrV)], and Stolbur (16SrXII). This study provides a comprehensive overview of the presence of phytoplasma strains and their vectors associated with GY complex, and their potential impact on viticulture of the South and East Asia. In general, both AY and EY were reported on several herbaceous plants and/or cultivated plants in South and East Asia, along with its vectors that were largely reported in China and sporadically in Japan. Interestingly, AY and EY are yet not found in South and East Asia grapevine regions; however, their presence on different plant species suggests the potential spread of the pathogens that may occur in grapevine regions in the near future. Additionally, a few reports also suggest the presence of Stolbur group in Asian countries, along with one study that found a Stolbur-related strain in China on Vitis vinifera. Similarly, PnWB was also frequently reported in India and China on several plant species, but not in grapes. Conversely, sporadic detections of phytoplasma strains related to X-disease in Thailand, South Korea, and China indicate that their potential influence in viticulture is rather negligible. Our review suggests that monitoring and control strategies against GY are essential in order to prevent epidemic phytoplasma spread, especially in vine-allocated areas in Asia.

Proposal of A New Bois Noir Epidemiological Pattern Related to ‘Candidatus Phytoplasma Solani’ Strains Characterized by A Possible Moderate Virulence in Tuscany

“…Bois noir (BN), one of the most important GY disease, is associated with 'Candidatus Phytoplasma solani' (CaPsol, taxonomic subgroup 16SrXII-A). CaPsol largely spread in Europe, Mediterranean regions and Iran, and has been sporadically reported from China, Chile, and South Africa [1][2][3]. In grapevine, BN induces symptoms undistinguishable from those of other GY diseases, such as desiccation of inflorescences, berry shrivel, leaf discolorations, reduction in growth, and irregular ripening of wood [4].…”

Biochemical Changes in Leaves of Vitis vinifera cv. Sangiovese Infected by Bois Noir Phytoplasma

“…Phytoplasmas are obligate plant-pathogenic organisms of the Mollicutes class, which infect many crops and hundreds of plant genera cultivated worldwide; thus, causing heavy economic losses [1,2]. Phytoplasmas have become an increasingly serious threat to many perennial plants, such as fruits, shrubs, woods, ornamental trees and, in particular, grapevine in Europe.…”

Influence of artificial inoculation by strains of phytopathogenic microorganisms isolated from different sources on physyological and biochemical parameters of galega orientalis plants

“…Відомо, що один вид молікуту може бути здатним до ураження декількох видів рослин, маючи широку філогенетичну спеціалізацію. Зокрема, виділені фітоплазми -збудники фітоплазмозу жовтої айстри (16SrI) й відьминих мітел арахісу (16SrII), які уражують овочеві культури [6] й виноградну лозу, але на цій культурі їх знаходять разом із стовбуром (16SrXII) та іншими видами молікутів у регіонах культивування виноградної лози у Південній і Східній Азії [7]. Тому питання філогенетичної спеціалізації молікутів потребує більш детального дослідження.…”