Crude extracts from several medicinal plants were investigated for their antimicrobial activities against Colletotrichum spp. in grapevines Extracts of sweet wormwood, cockscomb flowers, asian plantain flowers, and peach tree resin showed in vitro antifungal activity on growth of Colletotrichum acutatum. To test inhibition effects of ripe rot development by C. acutatum and C. gloeosporioides, grapevine leaves were sprayed with each extract (500 fold diluted) from sweet wormwood and cockscomb flower and leaves, asian plantain flower and peach tree resin. The crude extracts of medicinal plants displayed remarkable in vivo antimicrobial activities with inhibition of lesion development by 22.5 to 67.5 % in ‘Blanc seedless’ and 2.12 to 53.2% in ‘Thompson seedless’ inoculated with agar block of C. acutatum and by 19.2 to 61.5% in 'Blanc seedless' and 19.6 to 78.3% in ‘Thompson seedless’ grapevines inoculated with spore suspension of C. acutatum compared with the untreated control. The crude extracts of medicinal plants showed remarkable inhibition of ripe rot by 26 to 64.8 % in ‘Blanc seedless’ and 25.5 to 76.5% in ‘Thompson seedless’ grapevine leaves inoculated with C. gloeosporioides agar block inoculation and by 23.1 to 61.5% in 'Blanc seedless' and 18.8 to 25% in ‘Thompson seedless’ grapevine leaves inoculated with C. gloeosporioides spore suspension compared with uninoculated control. These findings indicate that medicinal plant extracts could be used as possible candidates to control ripe rot disease environment friendly in grapevines.

From 2010 to 2012, this study conducted to survey occurrence of quarantine diseases occurrence on cultivation, harvest period of grapevine, and sorting places for export grapevine in export complex areas(domestic vs. export; Hwaseong in Gyeonggii, Sangju and Yeongcheon in Kyeongbuk, Namwon in Jeonbuk and Yeongdong in Chungbuk). Diagnosed diseases in this study were gray mold by Botrytis cinerea, blact rot by Botryosphaeria dothidea, anthracnose by Colletotrichum gloeosporioides, bird,s eye rot by Elsinoe ampelina, Phomopsis cane by Phomopsis viticola, downy mildew by Plasmopara viticol, leaf blight by Pseudocercospora vitis, and powdery mildew by Uncinula necator. The leaf blight disease incidence and severity showed the highest infection rate in all surveyed fields. Occurrence rate of investigated all diseases was different depending on individual farmer and occurrence rate of disease was lower in export farms than that of domestic sale farms. Disease infested grapes were eliminated during selection process and ratio of removed the infection fruit is relatively well-performed in export facilities than domestic packing facilities.

국내야생종인 새머루로부터 내병성 포도품종 육성에 필요한 육종소재와 유용정보를 획득하고자, 포도 새눈무늬병균과 줄기혹병균에 감염된 새머루에서 식물 방어관련유전자의 발현양상을 분석하였다. Thaumatin (TLP), glutathione peroxidase (GPX), glutathione-S-transferase (GST), chalcone synthesis (CHS), protein kinase regulator (14-3-3) 및 β-glucanase (Glu) 등의 방어관련유전자, leucine reach-repeat (LRR)와 lipoxygenase (LOX) 등의 신호전달관련유전자, polygalacturonase-inhibiting protein (PGIP)과 같은 세포벽관련 유전자의 발현이 포도 새눈무늬병균 접종에 의해 유도되었다. 포도새눈무늬병균의 포자접종 및 배양여액처리에 의해 WRKYtranscription factor 10 (WRKY), fatty acid elongase (FAE)의 발현이 유도되었으며 proline-rich protein (PRP) 유전자의발현은 억제되었다. 발현이 증가한 15개 유전자 중에서 LRR, LOX, TLP, GST 등은 포도새눈무늬병균 포자현탁액 접종에 의해 발현이 크게 증가하였으나, CHS와 tonoplast intrinsicprotein (TIP)는 배양여액처리에 의해 증가하였다. 포도 줄기혹병균의 접종에 의해 LRR, CLP, LOX, TLP, GPX, 14-3-3,GST, PGIP, FAE, TIP, Glu, WRKY 등은 발현이 증가하였고, CHS와 PRPs는 발현이 억제되었다. 포도 줄기혹병균 접종에 의해 활성산소의 축적 및 분해와 관련된 GPX와 GST는 발현이 크게 증가하였다.

Pink Rot on melon and White Stain Symptom on grape are caused by Trichothecium roseum, one of the most important diseases of grape and melon. These diseases have been occurred in national-wide in Korea and causes irreversible damage on the grape and the melon at harvest season. This research presents the evaluation of the capacity of Bacillus subtillis HK2 to protect both melon and grape against T. reseum and establishes its role as a biocontrol agent. In this study, we isolated a Bacillus strain HK2 from rhizosphere soil, identified it as Bacillus subtillis by 16S rRNA analysis and demonstrated its antifungal activity against T. roseum. Under I-plate assay it was observed that the effect of hyphal growth inhibition was not due to production of volatile compounds. The optimum culture condition of HK2 was found at 30℃ and initial pH of 7.0. Application of HK2 culture suspension reduced 90.2% of white stain symptom on grape as compared to control, resulting in greater protection to grape against T. roseum infestation. Butanol extract of HK2 culture purified using flash column chromatography. The antifungal material was a polar substance as it showed antifungal activity in polar elute. Therefore, our results indicated a clear potential of B. subtilis HK2 to be used for biocontrol of Pink rot in melon and white stain symptom on grape caused by T. roseum.

It is necessary to evaluate the resistance to disease among genetic resources for development of disease resistant grapes. This study was conducted to screen the resistance to crown gall in muscadine and Florida hybrid bunch grapes by pathogen inoculation. In order to compare the responses to infection with different pathogen strains, muscadine and Florida hybrid grapes were inoculated with 3 strains of Agrobacterium vitis. Although there were different levels crown gall formation among grape cultivars, there little variation in response to inoculated strains. Among 29 muscadine cultivars tested by inoculation of A. vitis ‘C4612’, most of them were shown to be susceptible, and ‘Gold Isle’ and ‘Africa Queen’ were highly susceptible, and two cultivars, ‘Welder’ and ‘Jumbo’ were found to be resistant to crown gall disease. Among Florida hybrid grapes, ‘Daytona’, ‘Stover’, and ‘Swanee’ were susceptible and ‘Blanc du Bois’ was moderately susceptible to crown gall. Because muscadine grapes have been actively utilized as useful genetic resources for development of new grape varieties by intersub-genus cross, this result from the screening of resistance among muscadine grapes can provide valuable information in breeding programs of grape resistant to crown gall.