Instituto de Ciências Biomédicas, São Paulo, SP, Brazil.
J Sci Food Agric. 2010 Jul;90(9):1445-51. doi: 10.1002/jsfa.3962.
The aim of this study was to characterise the mycoflora and the presence of fumonisin in sorghum grains, correlating the results with the environment and abiotic factors.
Fifty samples (five collections of ten samples each) of sorghum were analysed. All samples were found to be contaminated with fungi, with higher frequencies of Cladosporium spp. (61.8%) and Helminthosporium spp. (33.4%). Fusarium verticillioides was isolated from 15.1% of the samples, with 38% of them being contaminated with fumonisin B(1) (FB(1)) at levels ranging from 50 to 368.78 ng g(-1). Regarding abiotic factors, temperature, water activity and rainfall showed a positive correlation with the frequency of F. verticillioides and FB(1) production. There was a significant positive correlation between relative air humidity and FB(1) production. The results obtained from sexual crosses between standard F mating tester strains and the isolated strains confirmed that the strains isolated were F. verticillioides.
It can be concluded that the decrease in F. verticillioides and fumonisin contamination occurred owing to atypical climatic factors during the period of sorghum cultivation, when there was any occurrence of rain and the level of water activity of grains did not reach 0.58.
本研究旨在对高粱籽粒中的真菌区系和伏马菌素的存在进行特征描述，将结果与环境和非生物因素相关联。
分析了 50 个高粱样本（每 10 个样本 5 个采集）。所有样本均被真菌污染，其中较高频率的是枝孢属（Cladosporium spp.）（61.8%）和镰刀菌属（Helminthosporium spp.）（33.4%）。从 15.1%的样本中分离出了轮枝镰孢菌（Fusarium verticillioides），其中 38%的样本污染了伏马菌素 B(1)（FB(1)），含量范围为 50 至 368.78 ng g(-1)。关于非生物因素，温度、水活度和降雨量与 F. verticillioides 的频率和 FB(1)的产生呈正相关。相对空气湿度与 FB(1)的产生呈显著正相关。通过标准 F 交配测试菌株与分离菌株之间的有性杂交获得的结果证实，分离出的菌株为轮枝镰孢菌。
可以得出结论，伏马菌素污染减少是由于高粱种植期间出现了非典型气候因素，导致有降雨发生，且谷物水活度未达到 0.58。
