清水苜蓿土壤浸提液对连作马铃薯根际土壤环境酶活性和微生物群落的影响

doi:10.3969/j.issn.1004-1524.2022.02.04

浙江农业学报 ›› 2022, Vol. 34 ›› Issue (2): 240-247.DOI: 10.3969/j.issn.1004-1524.2022.02.04

清水苜蓿土壤浸提液对连作马铃薯根际土壤环境酶活性和微生物群落的影响

袁文雅(), 康益晨, 杨昕宇, 张茹艳, 周春涛, 王勇, 陈喜鹏, 余慧芳, 秦舒浩^*()

甘肃农业大学园艺学院,甘肃兰州 730070

收稿日期:2021-05-31 出版日期:2022-02-25 发布日期:2022-03-02
作者简介:秦舒浩,E-mail: qinsh@gsau.edu.cn
袁文雅(1996—),女,甘肃庆阳人,硕士研究生,研究方向为蔬菜栽培与土壤生理生态。E-mail: 513208918@qq.com
通讯作者: 秦舒浩
基金资助:
国家自然科学基金(32060441);国家重点研发计划子课题(2018YFD0200803);马铃薯产业技术体系(CARS-09-P14)

Effects of rhizosphere soil extract of Qingshui alfalfa (Medicago sativa L.) on enzyme activities and microbial communities in rhizosphere soil of continuous cropping potato

YUAN Wenya(), KANG Yichen, YANG Xinyu, ZHNAG Ruyan, ZHOU Chuntao, WANG Yong, CHEN Xipeng, YU Huifang, QIN Shuhao^*()

College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China

Received:2021-05-31 Online:2022-02-25 Published:2022-03-02
Contact: QIN Shuhao

摘要/Abstract

摘要：

为缓解马铃薯连作障碍,以新大坪马铃薯为供试材料进行盆栽试验,设置4年龄清水苜蓿根际土壤浸提液与水5种不同配比(1∶1、2∶1、3∶1、4∶1、5∶1)混合液作为处理,以浇灌等量水作为对照组(CK),探究不同浓度清水苜蓿土壤浸提液对连作马铃薯根际土壤环境酶活性和微生物群落的影响。结果表明,4∶1混合液处理的土壤过氧化氢酶活性、碱性磷酸酶活性较对照组提高10.14%、47.65%,厌氧型自生固氮菌、反硝化细菌的数量较对照组增加54.80%、36.78%,马铃薯产量较对照组提高10.52%;3∶1混合液处理的土壤脲酶和蔗糖酶活性比对照组提高51.70%、55.27%,细菌、放线菌和好氧型自生固氮菌数量比对照组增加7.77%、58.91%、47.57%,同时有效地降低了真菌的数量,比对照组降低12.42%;1∶1混合液处理的土壤过氧化氢酶活性仅低于4∶1混合液处理,好氧型自生固氮菌数量仅低于3∶1混合液处理;综合比较各项指标,2∶1和5∶1混合液处理的效果相对较差。不同浓度清水苜蓿土壤浸提液均可提高马铃薯根际土壤环境酶活性与部分微生物数量,降低真菌数量,进而有效改善根际土壤环境微生物群落结构,缓解马铃薯连作障碍,提高马铃薯产量;其中,4∶1混合液处理改善效果最佳。

关键词: 马铃薯, 苜蓿, 轮作, 土壤, 微生物群落, 产量

Abstract:

In order to alleviate the continuous cropping obstacle of potato, a pot experiment was carried out with Xindaping potato as the test material. Five different ratios of 4-year-old Qingshui alfalfa (Medicago sativa L.)rhizosphere soil extracts and water mixed solution (1∶1, 2∶1, 3∶1, 4∶1, 5∶1) were set as treatments, and the control group(CK) was irrigated with the same amount of water. Effects of different concentrations of Qingshui alfalfa rhizosphere soil extracts on enzyme activities and microbial communities in continuous cropping potato rhizosphere soil environment was explored. The results showed that catalase and alkaline phosphatase activities in soil treated with the mixed solution (4∶1) were enhanced by 10.14% and 47.65% compared with CK. Compared with CK, number of anaerobic autogenic nitrogen-fixing bacteria and denitrifying bacteria increased by 54.80% and 36.78% and the potato yield was improved by 10.52%. Treated with mixed solution (3∶1), activities of urease and sucrase in soil were increased by 51.70% and 55.27% compared with CK. Compared with the CK, number of bacteria, actinomycetes and aerobic autogenic nitrogen-fixing bacteria were improved by 7.77%, 58.91% and 47.57%. And the number of fungi was significantly reduced, 12.42% lower than CK.Soil catalase activity of the mixed solution of 1∶1 was only lower than that of the mixed solution of 4∶1, and number of aerobic autogenic nitrogen-fixing bacteria was only lower than that of the mixed solution of 3∶1. Considering all these indicators, effect of treatment with mixed solution 2∶1 and 5∶1 were relatively poor. Different concentrations of Qingshui alfalfa soil extracts might increase enzyme activity and the number of some microorganisms, and reduce the number of fungi in potato rhizosphere soil environment. Thus, microbial community structure might be effectively ameliorated in the rhizosphere soil environment, thereby alleviating the continuous cropping obstacles of potato, and improving potato yield. Moreover, mixed solution with (4∶1) had the best effect.

Key words: potato, alfalfa, crop rotation, soil, microbial community, yield

中图分类号:

S532

袁文雅, 康益晨, 杨昕宇, 张茹艳, 周春涛, 王勇, 陈喜鹏, 余慧芳, 秦舒浩. 清水苜蓿土壤浸提液对连作马铃薯根际土壤环境酶活性和微生物群落的影响[J]. 浙江农业学报, 2022, 34(2): 240-247.

YUAN Wenya, KANG Yichen, YANG Xinyu, ZHNAG Ruyan, ZHOU Chuntao, WANG Yong, CHEN Xipeng, YU Huifang, QIN Shuhao. Effects of rhizosphere soil extract of Qingshui alfalfa (Medicago sativa L.) on enzyme activities and microbial communities in rhizosphere soil of continuous cropping potato[J]. Acta Agriculturae Zhejiangensis, 2022, 34(2): 240-247.

图/表 6

表1 供试土壤理化性质

Table 1 Physio-chemical properties of tested soils

供试土壤 Experimental soil	速效氮 Available nitrogen/ (mg·kg^-1)	速效磷 Available phosphorus/ (mg·kg^-1)	速效钾 Available potassium/ (mg·kg^-1)	pH值 pH value	电导率 Conductivity/ (mS·m^-1)	阳离子交换量 Cation exchange capacity/ (cmol·kg^-1)
清水苜蓿根际土壤Qingshui alfalfa rhizosphere soil	9.78	15.11	41.44	7.92	147.43	204.14
马铃薯根际土壤Potato rhizosphere soil	11.78	13.71	142.42	7.90	186.13	211.02

图1 清水苜蓿土壤浸提液对马铃薯根际土壤酶活性的影响 CK,对照组(灌溉等量水);T1~T5,清水苜蓿根际土壤浸提液与水1∶1、2∶1、3∶1、4∶1、5∶1配比。无相同小写字母表示差异显著(P<0.05)。下同。

Fig.1 Effects of Qingshui alfalfa soil extracts on potato rhizosphere soil enzyme activities CK,Control group (irrigated with the same amount of water); T1-T5, Qingshui alfalfa rhizosphere soil extracts and water mixed by 1∶1, 2∶1, 3∶1, 4∶1, 5∶1. Data marked without the same lowercase letters indicated significant differences at P<0.05. The same as below.

表2 清水苜蓿土壤浸提液对马铃薯根际土壤细菌、真菌和放线菌数量的影响

Table 2 Effects of Qingshui alfalfa soil extracts on the number of bacteria, fungi and actinomycetes in potato rhizosphere soil 105 CFU·g-1

处理 Treatment	细菌 Bacteria	真菌 Fungus	放线菌 Actinomycetes
CK	401.8±3.3 b	33.0±1.0 b	20.2±0.8 d
T1	406.9±26.2 ab	39.4 ±1.9 a	29.3±1.2 c
T2	395.6±9.6 ab	29.4±0.1 c	31.3±1.1 ab
T3	433.0±21.6 a	28.9±1.2 c	32.1±1.4 a
T4	426.7±11.8 ab	38.2±0.6 a	30.1±0.8 bc
T5	411.0±23.0 ab	40.2±1.0 a	29.6±0.7 bc

图2 清水苜蓿土壤浸提液对马铃薯根际土壤自生固氮菌数量的影响

Fig.2 Effects of Qingshui alfalfa soil extracts on the number of voluntary nitrogen-fixing bacteria in potato rhizosphere soil

图3 清水苜蓿土壤浸提液对马铃薯根际土壤硝化细菌数量的影响

Fig.3 Effects of Qingshui alfalfa soil extracts on the number of nitrifying bacteria in potato rhizosphere soil

图4 清水苜蓿土壤浸提液对马铃薯产量的影响

Fig.4 Effects of Qingshui alfalfa alfalfa soil extracts on potato yield

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清水苜蓿土壤浸提液对连作马铃薯根际土壤环境酶活性和微生物群落的影响

Effects of rhizosphere soil extract of Qingshui alfalfa (Medicago sativa L.) on enzyme activities and microbial communities in rhizosphere soil of continuous cropping potato

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