论文部分内容阅读
Fusarium asiaticum is the primary causal agent of Fusarium head blight (FHB) of wheat in southern China.Carbendazim has been extensively used for the control of FHB, resulting in severe carbendazim resistance in China, especially in Anhui Province.Fungal populations were collected throughout Anhui Province between 2010 and 2012 in order to determine their sensitivity to carbendazim.A total of 899 single-spore F.asiaticum isolates were collected and 74 isolates were resistant to carbendazim from all the sampled cities of Anhui Province with the overall carbendazim resistance frequency of 8.2%.Among these 74 isolates, the numbers of lowly resistant (LR), moderately resistant (MR), and highly resistant (HR) isolates were 1, 68 and 5, respectively.It could be concluded that a single point mutation at codons 167, 198 or 200 of the β2-tubulin gene, resulting in substitution of amino acids,correlated with different levels of resistance.There are five kinds of point mutations, F167Y, E198L, E198K,F200Y and E198Q, in the β2-tubulin gene causing the resistance to carbendazim in the field-resistant isolates with the frequency 89.2%, 2.7%, 4.1%, 2.7% and 1.4%, respectively.Most of the selected carbendazim-sensitive and-resistant isolates appeared to possess different biological properties, however, this might not due to the resistance.As carbendazim resistance was generally widely spread throughout Anhui Province, the sensitivity of F.asiaticum populations to carbendazim should be constantly monitored and appropriate precautions against resistance development in natural populations should be taken into account.