title: Trichoderma Biodiversity of Agricultural Fields in East China Reveals a Gradient Distribution of Species.
abstract: We surveyed the Trichoderma (Hypocreales, Ascomycota) biodiversity in agricultural fields in four major agricultural provinces of East China. Trichoderma strains were identified based on molecular approaches and morphological characteristics. In three sampled seasons (spring, summer and autumn), 2078 strains were isolated and identified to 17 known species: T. harzianum (429 isolates), T. asperellum (425), T. hamatum (397), T. virens (340), T. koningiopsis (248), T. brevicompactum (73), T. atroviride (73), T. fertile (26), T. longibrachiatum (22), T. pleuroticola (16), T. erinaceum (16), T. oblongisporum (2), T. polysporum (2), T. spirale (2), T. capillare (2), T. velutinum (2), and T. saturnisporum (1). T. harzianum, T. asperellum, T. hamatum, and T. virens were identified as the dominant species with dominance (Y) values of 0.057, 0.052, 0.048, and 0.039, respectively. The species amount, isolate numbers and the dominant species of Trichoderma varied between provinces. Zhejiang Province has shown the highest diversity, which was reflected in the highest species amount (14) and the highest Shannon-Wiener diversity index of Trichoderma haplotypes (1.46). We observed that relative frequencies of T. hamatum and T. koningiopsis under rice soil were higher than those under wheat and maize soil, indicating the preference of Trichoderma to different crops. Remarkable seasonal variation was shown, with summer exhibiting the highest biodiversity of the studied seasons. These results show that Trichoderma biodiversity in agricultural fields varies by region, crop, and season. Zhejiang Province (the southernmost province in the investigated area) had more T. hamatum than Shandong Province (the northernmost province), not only in isolate amounts but also in haplotype amounts. Furthermore, at haplotype level, only T. hamatum showed a gradient distribution from south to north in correspondence analysis among the four dominant species. The above results would contribute to the application of Trichoderma biocontrol strains.
authors.affiliation: State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Jin-Liang
authors.initials: JL
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.affiliation: Analysis Center of Agrobiology and Environmental Science, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Li-Juan
authors.initials: LJ
authors.lastname: Mao
authors.affiliation: State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Xiao-Xiao
authors.initials: XX
authors.lastname: Feng
authors.affiliation: State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Chu-Long
authors.initials: CL
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Fu-Cheng
authors.initials: FC
authors.lastname: Lin
mesh_terms: D000383:Agriculture; D044822:Biodiversity; D002681:China; D004271:DNA, Fungal / Q000235:genetics*; D021903:DNA, Ribosomal Spacer / Q000235:genetics*; D014644:Genetic Variation; D006801:Humans; D012275:Oryza / Q000382:microbiology; D010802:Phylogeny; D012621:Seasons; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D013045:Species Specificity; D014242:Trichoderma / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D014908:Triticum / Q000382:microbiology; D003313:Zea mays / Q000382:microbiology
chemical_list: D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer