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葡萄白腐病菌侵染的主要条件是伤口和充分潮湿。对葡萄的任何绿色组织,通过伤口,都能发生侵染。在高湿度环境下,或在叶片吐水之际,水孔能成为侵染的途径。在葡萄穗上,它们是不可能作为伤口被肉眼分辨出来的,然而穗梗上的自然伤口足够为病菌所入侵。白腐病菌的孢子萌发和入侵,是与潮湿密切相关的。土壤由于下雨或灌溉而充分湿润,可由下列两条途径引起侵染:(1)水膜凝聚引起营养物质外溢,从而促使孢子萌发,以至进一步入侵。(2)由于葡萄的根压增高而引起叶片吐水,给病菌提高水、营养物质的供应量,导致入侵。群众经验早就指出,白腐病菌侵染葡萄的条件是潮湿和伤口,葡萄绿色组织的机械伤口都能成为侵染的途径。试验证明:蔓、果面和大穗轴如无伤口则侵染难于成功。因此在雹灾、暴风雨后或多雨年份往往引起白腐病的猖獗流行。按各地经验:白腐病的发生,沟边较园内重,篱架较棚架重,近地的果穗较架上的果穗重,管理粗放的果园较精细者重,多雨年份较早年重。这些现象都说明潮湿的环境有利于白腐病的发生。
Grape whiteworms infection is the main condition of wounds and full moisture. Any green tissue on the grapes can get infected through the wounds. Water holes can become a source of infection in high-humidity environments or when the leaves are spitting water. On the grape spikes, they can not be visually identified as wounds, however, the natural wounds on the spikes are large enough to invade the germs. The germination and invasion of white rot fungus spores are closely related to moisture. Soil is fully wetted by rain or irrigation and can be infested in two ways: (1) Aggregation of water causes nutrients to spill, causing germination of the spores and further invasion. (2) Due to the increase of the root pressure of the grape leaves spit water, to improve the supply of bacteria and water, nutrient supply, leading to invasion. The mass experience has long pointed out that the white rot bacteria invade the grapes under the conditions of moisture and wounds, and the mechanical wounds of grape green tissue can become the means of infection. Experiments show that: vine, fruit face and big cob such as no wound infection is difficult to succeed. As a result, hailstorms, storms or rainy years often cause the rampant prevalence of white rot. According to local experience: the occurrence of white rot, ditch than the garden weight, fence more than scaffolding, near the ears of the ears than the rack weight, the extensive management of orchards more refined, heavy years heavier rainy years. These phenomena all indicate that the humid environment is conducive to the occurrence of white rot.