葡萄枝干病害的发生流行规律与防控策略

Occurrence, epidemical regularity and control strategies for grape trunk diseases

葡萄枝干病害(Grape Trunk Diseases,GTDs)是一类由多种病原真菌引起的葡萄枝干性病害的统称。目前该类病害在国内外的葡萄生产区普遍发生,且缺乏高效的防控技术,导致发生区的葡萄产量和品质下降风险逐步加大。对葡萄枝干病害在世界范围内的发生危害、症状特点、病原菌种类、发生规律和防控技术等进行了全面综述,并对葡萄枝干病害未来的研究方向进行了展望。相关信息为今后葡萄枝干病害乃至其他果树枝干病害的发生与防控研究提供了一定的借鉴。

Grape trunk Diseases(GTDs) is a general term for the grape trunk diseases caused by a variety of pathogenic fungi, includes ESCA complex disease, Eutypa dieback, Botryosphaeria dieback,black foot disease and Diaporthe dieback. At present, GTDs happen in grape production area both at home and abroad, and it leads to a gradual increase in the risk of global grape yield and quality decline in case of lacking of efficient prevention and control technology. This paper provides a comprehensive review of the occurrence and damage of grape trunk diseases worldwide, their symptoms, pathogenic species, occurrence pattern and control measures, as well as an outlook on future research directions for grape trunk diseases. Firstly, this review documented most of reports of grape trunk disease from thirtysix countries in world, eight countries have found five kinds of GTDs, which are France, Spain, America, Australian, South Africa, Italy, Czech Republic and China, and seventeen countries have reported two or four kinds of GTDs. The more details were described in section one. Secondly, we listed typical symptoms of five main grape trunk diseases and their related pathogens. Thirdly, the epidemical regularity of each kind of GTDs is in detail documented and their developmental conditions(air temperature,relative humidity, rainfall, etc.) are described. Their main pathogens can be detected at the wound area caused by pruning or curved for covering with soil. Spore maturation and sporulation need humid environmental conditions and a wide temperature range from 5 to 40 ℃. After successive rains, conidia and sporangium of four kinds of GTDs spread through the air, except for black foot disease. Campylocarpon spp. and Cylindrocarpon spp. are the main pathogens of black foot disease, which lives in free water of the soil. Wounds at root site and interface of grafting position are probably the entrance for pathogens to infect black foot disease. Wounds caused by pruning supplied infection sites for the pathogens of other four kinds of GTDs. Moreover, integrated control strategies of GTDs were highlighted in fourth part. Some preventive strategies include advance or delay the pruning time and spray pesticides on the wound area, which aims to avoid peak period of spore releasing and reduce the contact between tree wounds and pathogens. Hot water treatment is also a commonly used method to reduce pathogens in plants. Once GTDs happens, cutting off the infected branches, injection of hydrogen peroxide into the canes, usage of wooden pegs inoculated with endophytic strains of Trichoderma atroviride to insert the infected parts of the canes are effective to control GTDs. In last part, we discussed biological and abiotic stresses(drought stress and water stress) related to GTDs. The stresses maybe induce the pathogens to change from latent state to pathogenic state. The expression of symptoms caused by stress is probably due to the reduction of host resistance. Other host stress factors, including freezing damage,damage to roots by transplanting, infestation of pathogenic nematodes, and non-optimal environmental conditions for growth(malnutrition or high-salt soil) are also related to GTDs symptoms of a variety of hosts However, some areas lack of a more detailed and in-depth understanding, for example, initial pathogen source and invasion conditions. Looking forward, field spore monitoring, molecular identification technology and X-ray scanning equipment can assist in quantifying the amount of field spores and judging whether the pathogen has successfully invaded. The cytological and genetic knowledge of fungal pathogenicity and toxicity can greatly promote the research on GTDs, clarify the role of pathogens in the occurrence and development. More important, genomics technology has been widely studied due to its pathogenic mechanism and excellent germplasm resource mining. This technology can also be applied to the analysis of important pathogenic factors or to screen out genetic loci or materials resistant to GTDs as a method to improve grape’s resistance. In summary, GTDs widely happen in world and lead to heavy loss. The research on the occurrence, epidemic pattern and action mechanism of GTDs are important to understand how to control them and also other fruit trunk diseases in the future.