Bacon C W, Hinton D M, Hinton A
Toxicology & Mycotoxin Research Unit, ARS, USDA, Russell Research Center, Athens, GA 30604, USA.
J Appl Microbiol. 2006;100(1):185-94. doi: 10.1111/j.1365-2672.2005.02770.x.
To determine the effects of concentrations of fusaric acid on the growth of several strains of the biocontrol bacterial endophyte Bacillus mojavensis and other species within the Bacillus subtilis group, as well as the genetic relationships within this small group of Gram-positive bacteria, and their antagonisms to Fusarium verticillioides, which produce fusaric acid.
The growth of 50 Bacillus strains and species were tested at two concentrations of fusaric acid determined in maize infected by an isolate of F. verticillioides. Molecular characterizations of the strains and species of bacteria were determined with an automated ribotyper. The growth of bacteria measured under both concentrations with an automated turbidometer, Bioscreen, indicated that fusaric acid was toxic to most strains of the bacterial endophyte B. mojavensis. However, the effects of these two concentrations on other Bacillus species varied in that fusaric acid was either bacteriocidal or bacteriostatic to most species.
These data indicate that the concentrations of fusaric acid are inhibitory to the growth of most Bacillus species, some of which are used as biocontrol agents. This suggests that the endophytic and saprophytic states of F. verticillioides and other Fusarium species cannot be controlled by fusaric-acid-sensitive Bacillus species.
Mycotoxic Fusarium species, such as F. verticillioides, are competitive because all produce fusaric acid, which is inhibitory to biocontrol bacteria, and mutants tolerant to fusaric acid must be developed in order to be effective on biocontrol bacteria.
确定镰刀菌酸浓度对几种生防细菌内生菌莫哈韦芽孢杆菌菌株以及枯草芽孢杆菌群内其他菌种生长的影响，以及这一小群革兰氏阳性细菌的遗传关系，及其对产生镰刀菌酸的轮枝镰孢菌的拮抗作用。
在一株轮枝镰孢菌分离株感染的玉米中测定的两种镰刀菌酸浓度下，测试了50株芽孢杆菌菌株和菌种的生长情况。使用自动核糖体分型仪对细菌菌株和菌种进行分子特征分析。用自动比浊仪Bioscreen在两种浓度下测量细菌的生长情况，结果表明镰刀菌酸对大多数内生细菌莫哈韦芽孢杆菌菌株有毒性。然而，这两种浓度对其他芽孢杆菌菌种的影响各不相同，因为镰刀菌酸对大多数菌种要么具有杀菌作用，要么具有抑菌作用。
这些数据表明，镰刀菌酸浓度对大多数芽孢杆菌菌种的生长具有抑制作用，其中一些菌种被用作生物防治剂。这表明轮枝镰孢菌和其他镰刀菌属的内生和腐生状态无法通过对镰刀菌酸敏感的芽孢杆菌菌种来控制。
产毒镰刀菌属物种，如轮枝镰孢菌，具有竞争力，因为它们都产生对生物防治细菌有抑制作用的镰刀菌酸，因此必须开发对镰刀菌酸耐受的突变体才能对生物防治细菌有效。
