当前位置: X-MOL 学术Eur. J. Agron. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Wheat cover crop alters soil microbial community and increases cucumber yield under different potassium regimes
European Journal of Agronomy ( IF 5.2 ) Pub Date : 2022-06-15 , DOI: 10.1016/j.eja.2022.126567
Danmei Gao, Dongmei An, Jiayao Liu, Jibo Shi, Xingang Zhou, Fengzhi Wu

Cover crops can promote the subsequent plant growth and improve soil potassium (K) fertility. However, whether and how wheat cover crop benefits cucumber growth and yield under different K regimes and their functional roles are still unclear. In this study, a two-year greenhouse experiment from spring 2017 to autumn 2018 was conducted to evaluate the effects of wheat cover crop on cucumber plant growth, nutrition and yield. Moreover, a litterbag experiment was carried out in the greenhouse in spring 2018 to investigate the nutrient dynamics during decomposition of wheat shoot and root residues under the two K regimes. Soil bacterial and fungal communities during residues decomposition were analyzed by high-throughput amplicon sequencing, and the abundances of total bacterial, fungal, Bacillus and Pseudomonas spp. communities were also estimated by quantitative PCR. The responses of cucumber growth to changes in the soil microbial communities induced by wheat cover crop were assessed by plant-soil feedback experiment. Wheat cover crop increased cucumber yield except for in spring 2017 and plant growth and K concentration at 70 d in spring 2018, and reduced K application did not weaken the beneficial effects of wheat on cucumber growth and yield. Decomposition rate and nutrient release of wheat shoot residue differed from root residue, but no differences in shoot or root residue decomposition rate and nutrient release between the two K regimes. Wheat shoot and root residues differently changed the abundances, compositions and diversities of soil bacterial and fungal communities. Wheat shoot residue increased total bacteria, Bacillus and Pseudomonas spp. community abundances compared with root residue irrespective of K regimes, and Bacillus spp. community abundance was higher in shoot residue with reduced K application than that with normal K application from 220 to 240 d. Wheat shoot residue decreased the Shannon and inverse Simpson diversities of soil bacterial and fungal communities compared with root residue from 200 to 240 d. Moreover, there was significant difference in these diversities of soil fungal community of root residue between the two K regimes except for 240 d. In addition, wheat cover crop caused more stable co-occurrence network with more positive and negative total links and wheat shoot residue had higher these links than root residue, while reduced K application decreased these links of both shoot and root residues. Feedback effects of changes in soil microbial communities induced by wheat cover crop on cucumber growth were positive, and such effect was stronger in shoot residue than in root residue irrespective of K regimes. Overall, wheat cover crop can alter soil microbial communities and enhance cucumber productivity through positive plant-soil feedbacks mediated by soil biota, and reduced K application did not weaken such beneficial effects.



中文翻译:

小麦覆盖作物改变土壤微生物群落并在不同钾制度下增加黄瓜产量

覆盖作物可促进后续植物生长,提高土壤钾肥力。然而,小麦覆盖作物是否以及如何在不同的钾制度下有益于黄瓜的生长和产量及其功能作用仍不清楚。本研究从 2017 年春季到 2018 年秋季进行了为期两年的温室试验,以评估小麦覆盖作物对黄瓜植株生长、营养和产量的影响。此外,2018 年春季在温室中进行了垃圾袋试验,研究了两种钾处理条件下小麦枝条和根茎分解过程中的养分动态。通过高通量扩增子测序分析残留物分解过程中的土壤细菌和真菌群落,以及总细菌、真菌、芽孢杆菌假单胞菌属spp. 社区也通过定量 PCR 进行了估计。通过植物-土壤反馈实验评估了黄瓜生长对小麦覆盖作物诱导的土壤微生物群落变化的响应。小麦覆盖作物除2017年春季和2018年春季70 d的植株生长和钾浓度增加外,均提高了黄瓜产量,减少施钾量并未削弱小麦对黄瓜生长和产量的有利作用。小麦茎秆的分解速率和养分释放与根茎不同,但两种钾处理的茎秆或根茎分解速率和养分释放没有差异。小麦芽和根残留物不同地改变了土壤细菌和真菌群落的丰度、组成和多样性。小麦芽渣增加细菌总数,芽孢杆菌假单胞菌属。与根残留物相比的群落丰度,不考虑 K 方案,和芽孢杆菌spp. 220~240 d,减施钾肥的茎秆群落丰度高于正常施钾的。与根茎相比,小麦芽渣在200~240 d降低了土壤细菌和真菌群落的香农和逆辛普森多样性。此外,除 240 d 外,两种 K 方案的根渣土壤真菌群落多样性均存在显着差异。此外,小麦覆盖作物引起了更稳定的共现网络,具有更多的正负总链接,小麦茎秆比根茎具有更高的这些关联,而减少施钾降低了茎秆和根茎的这些关联。小麦覆盖作物诱导的土壤微生物群落变化对黄瓜生长的反馈效应是正的,并且无论 K 方案如何,这种作用在枝条残渣中都比在根残渣中更强。总体而言,小麦覆盖作物可以通过土壤生物群介导的植物-土壤正反馈来改变土壤微生物群落并提高黄瓜生产力,而减少钾的施用并未削弱这种有益效果。

更新日期:2022-06-17
down
wechat
bug