摘要：

为了研究东北春麦区不同轮作模式下土壤中小麦赤霉菌的含量和真菌群落组成特点,以小麦-小麦-马铃薯轮作(T)、小麦-小麦-水飞蓟轮作(MT)、小麦-小麦-油菜轮作(R)、小麦-小麦-甜菜轮作(S)和小麦-小麦-小麦连作(W)为对象,利用MiSeq 高通量测序平台ITS2扩增子测序技术,测定土壤真菌群落组成、多样性及小麦赤霉菌相对丰度。数据显示,土壤中真菌OTUs数目在小麦连作,小麦与马铃薯、水飞蓟、油菜和甜菜轮作中分别为:389,362,390,471,438个。油菜和甜菜与小麦轮作模式中,Chao1指数较小麦连作分别增加了11.08%和8.59%。结果表明,水飞蓟、油菜和甜菜与小麦轮作增加了土壤真菌的丰富度。水飞蓟和小麦轮作模式的Shannon指数和Simpson指数在5种种植模式中最高,表明该处理的土壤真菌群落多样性更好。5种不同种植模式中土壤真菌群落结构相似性聚类分析显示,4种轮作模式聚为一支。4种轮作模式与连作相比,担子菌门丰度增加,接合菌门丰度降低。与小麦连作相比,油菜、甜菜和水飞蓟与小麦轮作模式中,玉蜀黍赤霉的相对丰度分别下降了16.67%,50.00%,83.33%,并且有益菌群明显富集。然而,马铃薯与小麦轮作模式中玉蜀黍赤霉丰度显著增加。综上所述,在东北春麦区建议选择水飞蓟、甜菜和油菜与小麦轮作以减轻小麦赤霉病的危害。

关键词: 小麦, 轮作模式, 真菌群落, 小麦赤霉菌

Abstract:

To explore the abundance of Gibberella zeae and the composition and diversity of fungal communities in spring wheat belt of the Northeast, bulk soil samples were collected under four crop rotation patterns, such as wheat-wheat-potato (T), wheat-wheat-silybum marianum (MT), wheat-wheat-oilseed rape (R), wheat-wheat-sugarbeet (S), and wheat for three years (W) was used as control. The Illumina MiSeq was used to sequence the ITS amplicons of the strains. The data showed that the number of fungal OTUs in W, T, MT, R and S was 389, 362, 390, 471 and 438, respectively. In the R and S rotation pattern, Chao1 were increased 11.08% and 8.59% respectively, compared with wheat continuous cropping, indicating that the rotation of silybum marianum, oilseed rape and sugarbeet with wheat increased the abundance of fungi genus. Among the five planting patterns, Shannon and Simpson in MT were the highest, revealed that the diversity of fungal communities in MT was more enriched. The similarity cluster analysis of fungal community structure showed that the four rotation patterns clustered into one branch. Under the four cropping rotation patterns, the abundance of basidiomycota increased while that of Zygomycota decreased. We also found that the relative abundance of Gibberella zeae decreased by 16.67%, 50.00% and 83.33% in R, S and MT, respectively, while the abundance of friendly genus were remarkably increased. However, the relative abundance of Gibberella zeae was increased significantly in the T pattern. Based on the above research results and the local planting structure, it is suggested to plant silybum marianum, sugarbeet and oilseed rape rotation with wheat to reduce the hazard of wheat scab.

Key words: Wheat, Crop rotation patterns, Fungal communities, Gibberella zeae