Location: Agroecosystems Management ResearchTitle: Organic amendments improve wheat root growth and yield through regulating soil properties
|ZHAO, LILI - Northwest Agricultural & Forestry University|
|LI, LUSHING - North China University Of Water Conservancy And Electric Power|
|CAI, HUANJIE - Northwest Agricultural University|
|FAN, JUNILIANG - Northwest Agricultural University|
|CHAU, HENRY - Lincoln University - New Zealand|
|Malone, Robert - Rob|
|ZHANG, CHAO - Northwest Agricultural University|
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/27/2018
Publication Date: 2/21/2019
Citation: Zhao, L., Li, L., Cai, H., Fan, J., Chau, H.W., Malone, R.W., Zhang, C. 2019. Organic amendments improve wheat root growth and yield through regulating soil properties. Agronomy Journal. 111(2):482-495. https://doi.org/10.2134/agronj2018.04.0247.
Interpretive Summary: Organic amendments can prevent soil degradation and sustain crop production, but their effects on root growth have not been fully investigated. A field experiment (2014–2016) was conducted to investigate the impacts of several different organic amendments on soil properties, root growth and grain yield of winter wheat in the Guanzhong Plain (GZP) of China. Organic amendments improved soil fertility by increasing organic matter and total nitrogen in the soil surface compared to the control treatment without organic amendments. Organic amendments improved soil structure and root growth by increasing soil aggregate stability and soil macroporosity (relatively large soil pores). Compared to the control treatment, organic amendments significantly increased the root length and mass of the winter wheat at the flowering stage. Importantly, the wheat straw treatment (MWS) had the greatest grain yield among all five treatments with better soil fertility and structure. These results 1) suggest that the wheat straw treatment is an effective method to improve soil properties and crop productivity in the GZP and 2) help provide a more complete understanding of the relationship between soil properties and root growth. This research will 1) help soil scientists more fully understand the relationship between organic amendments, crop production, root growth, and soil properties and 2) potentially lead to improved agricultural management practices to prevent soil degradation and improve crop production.
Technical Abstract: Organic amendments prevent soil degradation and sustain crop production, but their effects on root growth and the functional responses of root growth to variations in soil properties have not been fully understood. A field experiment (2014–2016) was conducted to investigate the impacts of organic amendments on soil properties, root growth and grain yield of winter wheat (Triticum durum Desf.) in the Guanzhong Plain (GZP) of China. Five treatments were: application of mineral fertilizer alone (control, CO) and along with 20 Mg ha-1 of wheat straw (MWS), wheat husk (MWH), farmyard soil (MFS) and bioorganic fertilizer (MBF). Organic amendments improved soil fertility by increasing soil organic matter (7–15%) and total soil nitrogen (5–15%) in the 0– to 40–cm depth compared to the CO treatment. Meanwhile, organic amendments improved soil structure by increasing soil water stable aggregates >0.25 mm (WSA, 5–16%) and macroporosity (e10, 27–47%). Compared to the CO treatment, organic amendments significantly increased the root length density (RLD) and root mass density (RMD) in the 20 cm depth of soil at the flowering stage. The significantly higher RLD and RMD were also exhibited in the MWH and MFS treatments in the 20– to 100–cm depth. Additionally, the responses of RLD and RMD to WSA and e10 were well-described by quadratic equations based on all treatments. Importantly, the MWS treatment had the greatest grain yield among all five treatments with better soil fertility and structure. We suggested that the MWS treatment is an effective method for improving soil properties and crop productivity in the GZP.