Phytopathology. 1999 Dec;89(12):1162-8. doi: 10.1094/PHYTO.1999.89.12.1162.
ABSTRACT Pear blossoms were sampled during various stages of bloom in 1991 and 1992 from orchards at Cashmere, WA, and Corvallis and Medford, OR, for epiphytic populations of culturable bacteria. On stigmatic surfaces, bacteria were isolated from 2 to 32% of blossoms prior to petal expansion and from 47 to 94% of blossoms by petal fall. In general, a lower percentage of hypanthia than stigmas supported bacterial populations. Randomly selected bacteria isolated at population levels of >/=10(4) CFU/tissue were identified by fatty acid methyl ester analysis. Diverse genera of gram-negative and -positive bacteria were identified from the Medford and Cashmere field sites. Pseudomonas syringae and Pseudomonas viri-diflava were isolated from all sites and were the predominant species detected at Corvallis, where they were isolated from 28% of the blossoms sampled on a given date. Because most pear blossoms do not support detectable populations (>/=10(2) CFU/tissue) of culturable bacteria prior to petal expansion, we speculate that introduced biocontrol agents may become established with minimal competition from indigenous epiphytes at early bloom stages.
1991 年和 1992 年，在华盛顿州的 Cashmere 和俄勒冈州的 Corvallis 及 Medford 的果园里，对处于不同开花阶段的梨花进行了取样，以获取可培养细菌的附生种群。在柱头表面，在花瓣展开前，从 2%到 32%的花朵中分离出细菌，在花瓣脱落时，从 47%到 94%的花朵中分离出细菌。一般来说，花托上支持细菌种群的比例低于柱头。从梅德福和 Cashmere 田间采集的细菌，其种群水平>=/=10(4) CFU/组织，随机选择并通过脂肪酸甲酯分析进行鉴定。从梅德福和 Cashmere 田间采集的细菌，其种群水平>=/=10(4) CFU/组织，随机选择并通过脂肪酸甲酯分析进行鉴定。从梅德福和 Cashmere 田间采集的细菌，其种群水平>=/=10(4) CFU/组织，随机选择并通过脂肪酸甲酯分析进行鉴定。从 Medford 和 Cashmere 田间采集的革兰氏阴性和阳性细菌的多个属被鉴定出来。从所有地点分离出丁香假单胞菌和梨火疫病菌，并且在 Corvallis 检测到的主要物种，它们从特定日期采集的花朵中占 28%。因为大多数梨花在花瓣展开前不支持可培养细菌的检测种群（>/=10(2) CFU/组织），所以我们推测，在早期开花阶段，引入的生物防治剂可能会在最小的来自本地附生菌的竞争中建立起来。
