Origin of Pathogens of Grapevine Crown Gall Disease in Hokkaido in Japan as Characterized by Molecular Epidemiology of Allorhizobium vitis Strains

Abstract

Crown gall is a globally distributed and economically important disease of grapevine and other important crop plants. The causal agent of grapevine crown gall is tumorigenic Allorhizobium vitis (Ti) strains that harbor a tumor-inducing plasmid (pTi). The epidemic of grapevine crown gall has not been widely elucidated. In this study, we investigated the genetic diversity of 89 strains of Ti and nonpathogenic A. vitis to clarify their molecular epidemiology. Multi-locus sequence analysis (MLSA) of the partial nucleotide sequences of pyrG, recA, and rpoD was performed for molecular typing of A. vitis strains isolated from grapevines with crown gall symptoms grown in 30 different vineyards, five different countries, mainly in Japan, and seven genomic groups A to F were obtained. The results of MLSA and logistic regression indicated that the population of genetic group A was significantly related to a range of prefectures and that the epidemic of group A strains originated mainly in Hokkaido in Japan through soil infection. Moreover, group E strains could have been transported by infected nursery stocks. In conclusion, this study indicates that both soil infection and transporting of infected nursery stocks are working as infection source in Hokkaido.

Biological Control for Grapevine Crown Gall Evaluated by a Network Meta-Analysis

“…To clarify the factors affecting the biological control of antagonistic strains in 16 field trials, a regression analysis based on a linear mixed model (LMM) was performed. In this study, we followed the experimental methods described in previous reports [ 9 , 47 ]. The parameters, which were an antagonistic strain (categorical numbers: 0 = ARK-1, 1 = ARK-2, 2 = ARK-3, 3 = VAR03-1, an d4 = K84), concentrations of cell suspensions of the antagonist (categorical numbers: 0 = 5.0 × 10 7 cells/mL, 1 = 1.0 × 10 8 cells/mL, 2 = 2.0 × 10 8 cells/mL, and 3 = 1.0 × 10 9 cells/mL), field (categorical numbers: 0 = field A, 1 = field B, 2 = field C, and 3 = field D), and year (categorical numbers: 0 = 2006, 1 = 2007, 2 = 2008, 3 = 2009, 4 = 2010, 5 = 2011, 6 = 2012, 7 = 2013, 8 = 2015, 9 = 2016, and 10 = 2017) were coded and defined as explanatory variables.…”

“…GCG is a pandemic throughout the world [ 3 , 4 , 5 , 6 ]. Galls generally form on the trunks and cordons of young and mature grapevines [ 3 , 4 , 5 , 6 , 7 , 8 , 9 ]. Infected grapevines often experience inferior growth, but the galls cause grapevine death [ 7 ].…”

Insight into the population dynamics of pathogenic bacteria causing grapevine crown gall in snowfall areas: snow cover protects the proliferation of pathogenic bacteria

“…Rhizobium vitis , Agrobacterium vitis ] ( Mousavi et al., 2015 ) is a soil-dwelling bacterium, and grapevine ( Vitis vinifera L.) crown gall (GCG) is mainly caused by tumorigenic A. vitis (TAV). TAV infects grapevines in many vineyards and grape-growing regions through wounds such as freezing injuries, mechanical damage, and/or grafting ( Burr et al., 1998 ; Kawaguchi et al., 2017 ; Kawaguchi et al., 2021 ). GCG outbreaks have occurred worldwide ( Burr et al., 1998 ).…”

“…Currently, a new biopesticide made from ARK-1 is being developed and has shown positive results in field trials, effectively controlling crown gall in grapevine and other plant species. This new biopesticide is strongly required as GCG often occurs in Japan, particularly in Hokkaido ( Kawaguchi et al., 2017 ; Kawaguchi et al., 2021 ). Hokkaido is one of the world’s heaviest snowfall areas, with an average snowfall of 597 cm in Sapporo, the capital of Hokkaido, over the past 30 years according to the Japanese Meteorological Agency (JMA, http://www.jma.go.jp/jma/indexe.html ).…”

“…Hokkaido is one of the world’s heaviest snowfall areas, with an average snowfall of 597 cm in Sapporo, the capital of Hokkaido, over the past 30 years according to the Japanese Meteorological Agency (JMA, http://www.jma.go.jp/jma/indexe.html ). In many vineyards in Hokkaido, snow covers the whole grapevines every winter, protecting them from freezing injuries that often induce GCG in grapevines under approximately -20 °C air conditions ( Burr et al., 1998 ; Kawaguchi et al., 2017 ; Kawaguchi et al., 2021 ). Furthermore, grapevines under the snow (approximately 0°C) can avoid freezing injuries in snow-covered areas because the snow blocks out the extremely cold temperatures ( Jitsuyama et al., 2022 ).…”