This study examined the effect of interacting conditions of water activity (a_W, 0.995, 0.98 and 0.95) and temperature (15, 25 and 30 °C) on growth rate of two Fusarium thapsinum and one F. andiyazi strains isolated from sorghum in Argentina. In addition, the effect of interacting conditions (a_W × temperature × incubation time (7, 14, 21 and 28 days)) on mycotoxin production (moniliformin (MON), fusaric acid (FA) and fusarin C (FUS C)) on a sorghum grain substrate was evaluated. Statistical analysis showed that a_W and temperature significantly affected growth of both species, mainly the a_W. Incubation time significantly influenced mycotoxin production by both species as well, mostly for FA. Maximum growth rates of the F. thapsinum strains were obtained at the highest a_W (0.995) and 25 °C and growth rate decreased as a_W and temperature were reduced. The same growth profile was observed for F. andiyazi RCFA09 (maximum growth rates at 0.995–25 °C). Mycotoxin production by both species was detected at the highest a_W levels whereas at 0.95 a_W only low amounts of MON were produced by F. thapsinum. Maximum MON and FUS C production by both F. thapsinum strains was observed at 0.995 a_W and 25–30 °C after 28 days of incubation. Also, F. thapsinum strains showed maximum FA production at the highest a_W and temperature but after 14 days; after this incubation time toxin levels significantly decreased. The responses to a_W and temperature of F. andiyazi were similar to that of F. thapsinum strains in relation to FA and FUS C production. Maximum levels of FA were detected at the highest a_W after 14 days of incubation at 25–30 °C. Fusarin C was produced at all assayed temperatures but maximum levels were detected at 30 °C and 0.995 a_W after 28 days of incubation. Two-dimensional profiles on the interactions of a_W by temperature were developed from these data to identify conditions that indicate a significant risk from MON, FA and FUS C accumulation on sorghum grains. The results of this study suggest that sorghum grains could be colonized by these species and toxin production can occur, especially during development stages under field conditions at high water activity of grains or during grain storage if the drying process is slow or deficient. To our knowledge, this study described for the first time FUS C production by F. thapsinum and F. andiyazi under interacting conditions of a_W, temperature and incubation time on sorghum grains.

这项研究研究了水分活动（_W，0.995、0.98和0.95）和温度（15、25和30°C）的相互作用条件对从阿根廷高粱中分离出的两种镰刀菌葡萄和一株F. andiyazi菌株生长速率的影响。。此外，相互作用条件（_W  ×温度×孵育时间（7、14、21和28天））对霉菌毒素产生的影响（莫尼莫丁（MON），富沙酸（FA）和富沙林C（FUS C））评价高粱籽粒基质。统计分析表明，_W和温度显着影响两个物种的生长，主要是_W。孵化时间也显着影响两个物种的霉菌毒素产生，主要是对于FA。在最高_W（0.995）和25°C时，获得了番茄镰刀菌菌株的最大生长速率，并且随着_W和温度的降低，生长速率降低。F. andiyazi RCFA09观察到相同的生长曲线（在0.995–25°C时的最大生长速率）。两种真菌产生的毒素均以最高的_W水平检测到，而在0.95 a的_W下，番茄腐霉菌产生的MON量很小。在0.995 a _W下观察到两种葡萄球菌菌株的最大MON和FUS C产量孵育28天后，温度为25–30°C。此外，葡萄球菌菌株在最高的_W和温度下但在14天后显示出最大的FA产生。在该温育时间之后，毒素水平显着降低。就FA和FUS C的生产而言，F。andiyazi对_W.和iyazizi的_W和温度的响应与拟南芥F. thapsinum菌株的响应相似。在25–30°C下孵育14天后，在最高_W下检测到FA的最高水平。孵育28天后，在所有测定的温度下均产生了Fusarin C，但在30°C和0.995 a _W的条件下检测到最大水平。_W相互作用的二维轮廓从这些数据中得出温度变化曲线，以鉴定表明MON，FA和FUS C积累在高粱谷物上的重大风险的条件。这项研究的结果表明，高粱籽粒可能被这些物种定居，并且可能产生毒素，特别是在谷物水分活度较高的田间条件下的发育阶段，或者如果干燥过程缓慢或不足，则在谷物储存过程中。据我们所知，本研究首次描述了在高温，_W和温育时间对_W. thapsinum和F. andiyazi的影响下FUS C的生产。