Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora", IHSM-UMA-CSIC. Departamento de Microbiología, Facultad de Ciencias, Campus de Teatinos, 29071 Málaga, Spain.
Int Microbiol. 2017 Jun;20(2):95-104. doi: 10.2436/20.1501.01.289.
The biocontrol rhizobacterium Pseudomonas chlororaphis PCL1606 has the ability to protect avocado plants against white root rot produced by the phytopathogenic fungus Rosellinia necatrix. Moreover, PCL1606 displayed direct interactions with avocado roots and the pathogenic fungus. Thus, nonmotile (flgK mutant) and non-chemotactic (cheA mutant) derivatives of PCL1606 were constructed to emphasize the importance of motility and chemotaxis in the biological behaviour of PCL1606 during the biocontrol interaction. Plate chemotaxis assay showed that PCL1606 was attracted to the single compounds tested, such as glucose, glutamate, succinate, aspartate and malate, but no chemotaxis was observed to avocado or R. necatrix exudates. Using the more sensitive capillary assay, it was reported that smaller concentrations (1 mM) of single compounds elicited high chemotactic responses, and strong attraction was confirmed to avocado and R. necatrix exudates. Finally, biocontrol experiments revealed that the cheA and fglK derivative mutants reduced root protection against R. necatrix, suggesting an important role for these biological traits in biocontrol by P. chlororaphis PCL1606. [Int Microbiol 20(2):94-104 (2017)].
生防根际细菌假单胞菌 PCL1606 能够保护鳄梨树免受植物病原菌丝核菌引起的白根腐病的侵害。此外，PCL1606 与鳄梨树根系和致病性真菌直接相互作用。因此，构建了非运动（flgK 突变体）和非趋化（cheA 突变体）PCL1606 衍生物，以强调运动性和趋化性在 PCL1606 生防相互作用中的生物学行为中的重要性。平板趋化性试验表明，PCL1606 被测试的单一化合物（如葡萄糖、谷氨酸、琥珀酸、天冬氨酸和苹果酸）所吸引，但对鳄梨树或丝核菌分泌物没有趋化性。使用更敏感的毛细管试验，报告称单一化合物的较小浓度（1mM）引起强烈的趋化反应，并证实对鳄梨树和丝核菌分泌物有强烈的吸引力。最后，生防实验表明，cheA 和 fglK 衍生突变体减少了对丝核菌的根保护作用，表明这些生物学特性在 P. chlororaphis PCL1606 的生防中起着重要作用。[《国际微生物学》20(2):94-104 (2017)]。
