Relationships Between Blueberry Flower Age, Pollination, and Conidial Infection by Monilinia vaccinii-corymbosi.
Relationships Between Blueberry Flower Age, Pollination, and Conidial Infection by Monilinia vaccinii-corymbosi.
复制标题
蓝莓花龄、授粉和 Monilinia vaccinii-corymbosi 分生孢子感染之间的关系。
作者：
H. Ngugi;H. Scherm;J. S. Lehman
牛痘疫霉通过雌蕊群途径感染开放的蓝莓花，导致发育中的果实木乃伊化。为了研究不同花龄对侵染的影响，用M.在开花后0至5天之间，在实验室中测量离体花中穿过花柱管的真菌生长速率，并确定温室中生长的植物中的果实病害发病率。菌丝生长速率在开花当天接种的花中最大，在接种时随着花龄的增加而线性下降（r = 0.921; P < 0.0001; n = 12），并且不受在接种时施加的花粉的存在或不存在的影响。在温室种植的植物中，受感染的果实的百分比呈指数下降，增加花龄接种（R = 0.878; P = 0.0057; n = 10），发病率范围从76.4%的花接种开花当天的15.5%，接种4天后。温室果实病害发病率与离体花菌丝生长速率呈线性相关（r = 0.985; P < 0.0001; n = 9），证明了在研究雌蕊群感染时使用离体花是合理的。牛痘-伞房花序在单独的实验中，授粉和接种的时间和顺序对菌丝通过花柱管的生长速率和发病率的影响进行了研究。花粉接种前1或2天的应用程序分离的花朵相比，同时接受花粉和分生孢子的花朵，菌丝生长率降低14.0和42.9%之间。同样，在温室种植的植物上观察到授粉至接种间隔为1至4天的果实病害发病率降低9.5%至18.3%。这些结果表明，新开放的花朵是最容易受到感染的M。vaccinii-corymbosi，并且如果授粉在接种前至少1天发生，则果实疾病发病率降低。策略，导致早期授粉的新开放的花朵可能是有用的管理木乃伊浆果疾病领域。
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.