Effects of maize continuous cropping on soil microbial community structure based on metagenomic analysis

doi:10.11686/cyxb2024042

Abstract

Abstract:

The aim of this study was to explore the effects of maize （Zea mays） continuous cropping on soil microorganisms. Soil samples were collected from the Ganzhou District of Zhangye City from fields continuously used to cultivate maize for 5， 10， 15， 20， and more than 21 years， and from Linze County from fields continuously used to cultivate maize for 10， 15， 20 and more than 21 years. The soil samples were subjected to metagenomic analyses. The results showed that the soil bacterial abundance in the two areas increased and then decreased as the number of years of continuous cropping increased， and the diversity continued to decrease with extended continuous cropping. Across the time series， the relative abundance of the dominant phyla Proteobacteria and Actinobacteria in Ganzhou District initially increased and then decreased， and had further significantly decreased at 20 years of continuous cropping （P<0.05）. The relative abundance of Acidobacteria in Linze County continued to decline， and was significantly lower at 20 years of continuous cropping than at 10 years （P<0.05）. With increasing number of years of continuous cropping， fungal abundance and diversity continued to increase. The relative abundance of the fungal genera Colletotrichum and Fusarium in Ganzhou District was significantly increased （P<0.05） at 15 and 20 years of continuous cropping， and that of Fusarium in Linze County fluctuated at 15 and 21 years of continuous cropping. Analyses of beta diversity revealed that the structure of soil bacterial and fungal communities differed significantly， depending on the number of years of continuous cropping. In Ganzhou District， metabolic pathways， microbial metabolism， carbon metabolism， and pyruvate metabolism functions of the microbial community were significantly lower （P<0.05） at 10 years than at 5 years of continuous cropping. In Linze County， metabolic pathways， biosynthesis of secondary metabolites， and pyruvate metabolism functions were significantly （P<0.05） higher at 20 years than at 10 years of continuous cropping. In contrast， two-component system functions were significantly （P<0.05） lower at 20 years than at 10 years of continuous cropping. The results of this study indicate that the duration of continuous cropping affects the diversity， community structure， and functions of soil microbes. The decrease in the relative abundance of Proteobacteria and Actinobacteria and the increase in the relative abundance of Colletotrichum and Fusarium in Ganzhou District， and the decrease in the relative abundance of Acidobacteria and the increase in the relative abundance of Fusarium in Linze County might contribute to maize continuous cropping decline. The results of our study provide a basis for unravelling the microbiological mechanism of continuous cropping decline.

Key words: maize, soil continuous cropping, metagenomic, soil microorganism, community structure

Chen-yang ZHANG, Meng-jun JIN, Yong-feng XU, Cheng-de YANG. Effects of maize continuous cropping on soil microbial community structure based on metagenomic analysis[J]. Acta Prataculturae Sinica, 2024, 33(12): 160-174.

Figures/Tables 19

References 46

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分组Group	样品编号Number of samples	采集地点Collection site	经度Longitude （E）	纬度Latitude （N）
GZ₁	GDM₁	甘州区大满镇Daman Township， Ganzhou District	100°24′05″	38°47′47″
	GJA₁	甘州区靖安乡Jingan Township， Ganzhou District	100°25′34″	39°05′42″
	GMY₁	甘州区明永镇Mingyong Township， Ganzhou District	100°18′29″	39°00′44″
GZ₂	GDM₂	甘州区大满镇Daman Township， Ganzhou District	100°24′05″	38°47′47″
	GJA₂	甘州区靖安乡Jingan Township， Ganzhou District	100°25′34″	39°05′42″
	GMY₂	甘州区明永镇Mingyong Township， Ganzhou District	100°18′29″	39°00′44″
LZ₂	LZBQ₂	临泽县板桥镇Banqiao Township， Linze County	100°17′08″	39°16′38″
	LNJ₂	临泽县倪家营镇Nijiaying Township， Linze County	100°07′43″	39°01′53″
	LXH₂	临泽县新华镇Xinhua Township， Linze County	100°01′17″	39°11′41″
GZ₃	GDM₃	甘州区大满镇Daman Township， Ganzhou District	100°24′05″	38°47′47″
	GJA₃	甘州区靖安乡Jingan Township， Ganzhou District	100°25′34″	39°05′42″
	GMY₃	甘州区明永镇Mingyong Township， Ganzhou District	100°18′29″	39°00′44″
LZ₃	LZBQ₃	临泽县板桥镇Banqiao Township， Linze County	100°17′08″	39°16′38″
	LNJ₃	临泽县倪家营镇Nijiaying Township， Linze County	100°07′43″	39°01′53″
	LXH₃	临泽县新华镇Xinhua Township， Linze County	100°01′17″	39°11′41″
GZ₄	GDM₄	甘州区大满镇Daman Township， Ganzhou District	100°24′05″	38°47′47″
	GJA₄	甘州区靖安乡Jingan Township， Ganzhou District	100°25′34″	39°05′42″
	GMY₄	甘州区明永镇Mingyong Township， Ganzhou District	100°18′29″	39°00′44″
LZ₄	LZBQ₄	临泽县板桥镇Banqiao Township， Linze County	100°17′08″	39°16′38″
	LNJ₄	临泽县倪家营镇Nijiaying Township， Linze County	100°07′43″	39°01′53″
	LXH₄	临泽县新华镇Xinhua Township， Linze County	100°01′17″	39°11′41″
GZ₅	GDM₅	甘州区大满镇Daman Township， Ganzhou District	100°24′05″	38°47′47″
	GJA₅	甘州区靖安乡Jingan Township， Ganzhou District	100°25′34″	39°05′42″
	GMY₅	甘州区明永镇Mingyong Township， Ganzhou District	100°18′29″	39°00′44″
LZ₅	LZBQ₅	临泽县板桥镇Banqiao Township， Linze County	100°17′08″	39°16′38″
	LNJ₅	临泽县倪家营镇Nijiaying Township， Linze County	100°07′43″	39°01′53″
	LXH₅	临泽县新华镇Xinhua Township， Linze County	100°01′17″	39°11′41″

分组Group	样品编号Number of samples	采集地点Collection site	经度Longitude （E）	纬度Latitude （N）
GZ₁	GDM₁	甘州区大满镇Daman Township， Ganzhou District	100°24′05″	38°47′47″
	GJA₁	甘州区靖安乡Jingan Township， Ganzhou District	100°25′34″	39°05′42″
	GMY₁	甘州区明永镇Mingyong Township， Ganzhou District	100°18′29″	39°00′44″
GZ₂	GDM₂	甘州区大满镇Daman Township， Ganzhou District	100°24′05″	38°47′47″
	GJA₂	甘州区靖安乡Jingan Township， Ganzhou District	100°25′34″	39°05′42″
	GMY₂	甘州区明永镇Mingyong Township， Ganzhou District	100°18′29″	39°00′44″
LZ₂	LZBQ₂	临泽县板桥镇Banqiao Township， Linze County	100°17′08″	39°16′38″
	LNJ₂	临泽县倪家营镇Nijiaying Township， Linze County	100°07′43″	39°01′53″
	LXH₂	临泽县新华镇Xinhua Township， Linze County	100°01′17″	39°11′41″
GZ₃	GDM₃	甘州区大满镇Daman Township， Ganzhou District	100°24′05″	38°47′47″
	GJA₃	甘州区靖安乡Jingan Township， Ganzhou District	100°25′34″	39°05′42″
	GMY₃	甘州区明永镇Mingyong Township， Ganzhou District	100°18′29″	39°00′44″
LZ₃	LZBQ₃	临泽县板桥镇Banqiao Township， Linze County	100°17′08″	39°16′38″
	LNJ₃	临泽县倪家营镇Nijiaying Township， Linze County	100°07′43″	39°01′53″
	LXH₃	临泽县新华镇Xinhua Township， Linze County	100°01′17″	39°11′41″
GZ₄	GDM₄	甘州区大满镇Daman Township， Ganzhou District	100°24′05″	38°47′47″
	GJA₄	甘州区靖安乡Jingan Township， Ganzhou District	100°25′34″	39°05′42″
	GMY₄	甘州区明永镇Mingyong Township， Ganzhou District	100°18′29″	39°00′44″
LZ₄	LZBQ₄	临泽县板桥镇Banqiao Township， Linze County	100°17′08″	39°16′38″
	LNJ₄	临泽县倪家营镇Nijiaying Township， Linze County	100°07′43″	39°01′53″
	LXH₄	临泽县新华镇Xinhua Township， Linze County	100°01′17″	39°11′41″
GZ₅	GDM₅	甘州区大满镇Daman Township， Ganzhou District	100°24′05″	38°47′47″
	GJA₅	甘州区靖安乡Jingan Township， Ganzhou District	100°25′34″	39°05′42″
	GMY₅	甘州区明永镇Mingyong Township， Ganzhou District	100°18′29″	39°00′44″
LZ₅	LZBQ₅	临泽县板桥镇Banqiao Township， Linze County	100°17′08″	39°16′38″
	LNJ₅	临泽县倪家营镇Nijiaying Township， Linze County	100°07′43″	39°01′53″
	LXH₅	临泽县新华镇Xinhua Township， Linze County	100°01′17″	39°11′41″

地区 District	分组 Group	变形菌门 Proteobacteria	酸杆菌门 Acidobacteria	放线菌门 Actinobacteria
甘州区 Ganzhou District	GZ₁	24.58±0.00b	24.19±1.87b	4.17±0.12c
	GZ₂	25.89±0.25a	26.72±2.49b	7.15±0.02b
	GZ₃	26.66±0.81a	27.10±0.35b	12.21±2.35a
	GZ₄	19.78±0.03c	30.32±1.39a	8.70±1.62b
	GZ₅	19.75±0.96c	26.96±0.04b	3.27±0.58c
临泽县 Linze County	LZ₂	23.95±0.39b	27.46±0.36a	1.99±0.29c
	LZ₃	22.34±1.38c	25.58±1.37ab	4.30±0.25bc
	LZ₄	25.37±0.14a	23.66±0.51b	7.70±1.00b
	LZ₅	26.30±0.44a	20.60±2.03c	12.57±4.91a

地区 District	分组 Group	变形菌门 Proteobacteria	酸杆菌门 Acidobacteria	放线菌门 Actinobacteria
甘州区 Ganzhou District	GZ₁	24.58±0.00b	24.19±1.87b	4.17±0.12c
	GZ₂	25.89±0.25a	26.72±2.49b	7.15±0.02b
	GZ₃	26.66±0.81a	27.10±0.35b	12.21±2.35a
	GZ₄	19.78±0.03c	30.32±1.39a	8.70±1.62b
	GZ₅	19.75±0.96c	26.96±0.04b	3.27±0.58c
临泽县 Linze County	LZ₂	23.95±0.39b	27.46±0.36a	1.99±0.29c
	LZ₃	22.34±1.38c	25.58±1.37ab	4.30±0.25bc
	LZ₄	25.37±0.14a	23.66±0.51b	7.70±1.00b
	LZ₅	26.30±0.44a	20.60±2.03c	12.57±4.91a

地区 District	分组 Group	未命名酸杆菌属Acidobacteria_noname	未命名β-变形菌属Beta-Proteobacterua_noname	未命名δ-变形菌属Delta-Proteobacteria_noname
甘州区 Ganzhou District	GZ₁	8.59±0.48b	1.46±0.02a	1.52±0.03a
	GZ₂	11.44±0.61a	1.66±0.08a	1.74±0.22a
	GZ₃	11.61±0.46a	1.84±0.44a	1.82±0.50a
	GZ₄	9.31±0.11b	1.73±0.23a	1.64±0.02a
	GZ₅	11.88±0.10a	1.47±0.05a	1.44±0.80a
临泽县 Linze County	LZ₂	12.17±0.28a	1.88±0.07a	2.24±0.17a
	LZ₃	9.94±0.39b	1.70±0.17a	1.78±0.09b
	LZ₄	11.36±0.62a	1.69±0.01a	1.57±0.07c
	LZ₅	8.85±0.90b	1.30±1.14b	1.50±0.07c