Phytopathology. 2002 Oct;92(10):1104-9. doi: 10.1094/PHYTO.2002.92.10.1104.
ABSTRACT Monilinia vaccinii-corymbosi infects open blueberry flowers via the gynoecial pathway, leading to mummification of the developing fruit. To determine the effect of flower age on infection, stigmata were inoculated with conidia of M. vaccinii-corymbosi between 0 and 5 days after anthesis, fungal growth rates through the stylar canal were measured in detached flowers in the laboratory, and fruit disease incidence was determined in plants grown in the greenhouse. Hyphal growth rates were greatest in flowers inoculated on the day of anthesis, declined linearly with increasing flower age at inoculation (r = 0.921; P < 0.0001; n = 12), and were unaffected by the presence or absence of pollen applied at the time of inoculation. In greenhouse-grown plants, the percentage of infected fruit decreased exponentially with increasing flower age at inoculation (R = 0.878; P = 0.0057; n = 10), with disease incidence ranging from 76.4% for flowers inoculated on the day of anthesis to 15.5% for those inoculated 4 days later. Fruit disease incidence in the greenhouse was linearly correlated with hyphal growth rates in detached flowers (r = 0.985; P < 0.0001; n = 9), justifying the use of detached flowers when investigating gynoecial infection by M. vaccinii-corymbosi. In separate experiments, the effects of timing and sequence of pollination and inoculation on hyphal growth rates through the stylar canal and on disease incidence were investigated. Application of pollen to detached flowers 1 or 2 days before inoculation reduced hyphal growth rates by between 14.0 and 42.9% compared with flowers that received pollen and conidia simultaneously. Similarly, reductions in fruit disease incidence by between 9.5 and 18.3% were observed on greenhouse-grown plants for pollination-to-inoculation intervals ranging from 1 to 4 days. These results document that newly opened flowers are most susceptible to infection by M. vaccinii-corymbosi and that fruit disease incidence is reduced if pollination occurs at least 1 day before inoculation. Strategies that lead to early pollination of newly opened flowers may be useful for managing mummy berry disease in the field.
Monilinia vaccinii-corymbosi 通过雌蕊途径感染开放的蓝莓花，导致发育中的果实变成木乃伊。为了确定花龄对感染的影响，在开花后 0 至 5 天内，将分生孢子接种到柱头的霉状物上，在实验室中测量分离花朵中通过花柱的真菌生长速度，并在温室中生长的植物上确定果实发病率。在开花当天接种的花朵中，菌丝生长速度最大，随着接种时花龄的增加呈线性下降（r = 0.921；P < 0.0001；n = 12），并且不受接种时花粉的存在与否的影响。在温室种植的植物中，感染果实的百分比随着接种时花龄的增加呈指数下降（R = 0.878；P = 0.0057；n = 10），发病率范围从开花当天接种的花朵的 76.4%到 4 天后接种的花朵的 15.5%。温室中果实发病率与分离花朵中菌丝生长速度呈线性相关（r = 0.985；P < 0.0001；n = 9），这证明了在调查 M. vaccinii-corymbosi 对雌蕊的感染时，使用分离花朵是合理的。在单独的实验中，调查了授粉和接种的时间和顺序对花柱中菌丝生长速度和发病率的影响。与同时接受花粉和分生孢子的花朵相比，在接种前 1 天或 2 天将花粉应用于分离花朵会使菌丝生长速度降低 14.0%至 42.9%。同样，在温室种植的植物上，授粉至接种间隔为 1 至 4 天，观察到果实发病率降低 9.5%至 18.3%。这些结果表明，新开放的花朵最容易受到 M. vaccinii-corymbosi 的感染，如果授粉至少在接种前 1 天进行，果实发病率就会降低。导致新开放花朵早期授粉的策略可能有助于田间管理木乃伊莓病害。
