梨园气溶胶中梨火疫病菌的定量检测

为系统研究梨园气溶胶中梨火疫病菌的含量, 本研究于2019年－2021年在新疆库尔勒市人和农场梨园, 利用病原菌孢子捕捉器在每年春季(4月下旬)、夏季(6月中旬)、秋季(9月中旬)收集梨园气溶胶, 检测梨火疫病菌。结果显示, 健康梨园气溶胶中未检测到梨火疫病菌, 不同发病程度的梨园气溶胶中均能检测到梨火疫病菌, 携菌量均值在102 cfu/(24cm2·h)以上, 其中, 气溶胶中梨火疫病菌含量最高值为2.81×104 cfu/(24cm2·h), 最低值为8.50×102 cfu/(24cm2·h); 重度、中度、轻度发病果园收集的气溶胶中含梨火疫病菌总菌落数均值分别为8.74×103、4.55×103、2.36×103 cfu/(24cm2·h)。此外, 在同一高度收集的气溶胶中, 梨火疫病菌菌落数随收集时间的延长而增加。不同季节气溶胶携菌量检测结果表明, 秋季发病梨园中气溶胶携菌量明显高于夏季和春季, 与梨园梨火疫病发病规律相符。致病性测定结果表明, 气溶胶中分离的梨火疫病菌具有致病性。

Quantitative detection of Erwinia amylovora in the aerosol of pear orchards

To systematically study the content of Erwinia amylovora in the aerosol of pear orchards, the aerosols of the pear orchards located in Xinjiang Korla Renhe Farm were collected by using pathogen spore trap during spring (late April), summer (mid-June), autumn (mid-September) from 2019 to 2021. The results showed that no E. amylovora was detected in the aerosol of healthy pear orchards, but it could be detected in the aerosols collected from the infected pear orchards with different degrees of disease, with an average amount of more than 102 cfu/(24cm2·h). The maximum and minimum values of E. amylovora were 2.81×104 cfu/(24cm2·h) and 8.50×102 cfu/(24cm2·h), respectively. The average amount of E. amylovora colonies in pear orchards with severe morbidity, moderate morbidity and light morbidity was 8.74×103, 4.55×103 cfu/(24cm2·h) and 2.36×103 cfu/(24cm2·h), respectively. In addition, the colony amount of E. amylovora in the aerosols at the same altitude increased with increasing collection time. The investigation of seasonal effect on the content of E. amylovora in the aerosols indicated that the amount of E. amylovora was higher in autumn than in spring and summer, which was consistent with the occurrence of E. amylovora on pear in the field. The pathogenicity test results confirmed that E. amylovora isolated from the aerosol was pathogenic.