title: Reducing environmental risk of excessively fertilized soils and improving cucumber growth by Caragana microphylla-straw compost application in long-term continuous cropping systems.
abstract: Continuous cropping is a common agricultural practice in the word. In China, farmers often apply excessive fertilizers to fields in an attempt to maintain yields in continuous cropping systems. However, this practice often results in high nutrient concentrations in soils, nutrient pollution in leaching water and more crop disease. Here, we investigated 8 different soils from continuously cropped cucumbers in Northern China that grouped into those with extremely high nutrient levels (EHNL) and those with lower nutrient levels (LNL). All soils were treated with Caragana microphylla-straw (CMS) compost addition, and then were used to measure soil physiochemical and microbial properties, leaching water quality, plant root growth and cucumber fruit yield. In general, the EHNL-soil showed higher nitrate, phosphorus and potassium concentrations in the leaching water compared to the LNL-soil. However, the CMS compost application increased soil nutrient and water holding capacities, total microbial biomass (bacteria and fungi), root length, plant biomass and fruit yields, but decreased nutrient concentrations in the leaching water from the EHNL-soil. In addition, the CMS compost decreased the number of Fusarium oxysporum f. sp. cucumerinum in soils with very high concentration of mineral nitrogen. Our results infer that CMS compost application was an effective method for reducing environmental risk of excessively fertilized soils.
authors.affiliation: Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, Department of Vegetable Science, China Agricultural University, 2 Yuanmingyuan Xilu, Beijing 100193, PR China. Electronic address: tianyq1984@cau.edu.cn.
authors.forename: Yongqiang
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, Department of Vegetable Science, China Agricultural University, 2 Yuanmingyuan Xilu, Beijing 100193, PR China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, Department of Vegetable Science, China Agricultural University, 2 Yuanmingyuan Xilu, Beijing 100193, PR China.
authors.forename: Weihua
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, Department of Vegetable Science, China Agricultural University, 2 Yuanmingyuan Xilu, Beijing 100193, PR China; Collaborative Innovation Center for Protected Vegetables in Round-Bohai Bay-Region, PR China. Electronic address: gaolh@cau.edu.cn.
authors.forename: Lihong
authors.initials: L
authors.lastname: Gao
mesh_terms: D000383:Agriculture / Q000379:methods*; D032602:Caragana; D002681:China; D018553:Cucumis sativus / Q000254:growth & development*; D005308:Fertilizers; D009566:Nitrates / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology
chemical_list: D005308:Fertilizers; D009566:Nitrates; D012987:Soil; D010758:Phosphorus
keywords: Caragana microphylla-straw compost; Continuously cropped cucumber; Environmental risk; Excessive fertilization; Plant growth