Tiltle:Enhance root-bleeding sap flow and root lodging resistance of maize under a combination of nitrogen strategies and farming practices

Authors: Hao Wang, Ranran Xu, Yang Li, Liye Yang, Wei Shi, Yongjie Liu, Shenghua Chang, Fujiang Hou, Qianmin Jia*

Journal：Agricultural Water Management（农林科学二区 IF₂₀₁₈=3.542）

DOI: 10.1016/j.agwat.2019.105742

Abstract: A cultivation technique in combination of nutrient strategies has not been implemented on root growth, rootbleeding sap, lodging resistance and production of corn. Therefore, we conducted field trials implementing different cultivation techniques (ridge-furrow system with film covered (RF), ridge-furrow system with soil crust(SC), and flat soil planting system with no ridge and no cover (TF); with four nitrogen levels: 300 kg N ha?1 (3);200 kg N ha?1 (2); 100 kg N ha?1 (1) and 0 kg N ha?1 (0), during 2015?2016. The aim of this work was to improve soil water storage, yield components, and production through regulating root growth and lodging resistance.The results showed that the RF system under different nutrient levels had significantly improved soil water storage, yield components which led to promote the development of roots in deep soil (0?50 cm) than that of SC and TF planting. The RF2 treatment significantly increased the root volume density (RVD), root weight

density (RWD), and root diameter at various growth stages and attained the maximum value at 125 DAP (except root diameter) than that of TF2 treatment. The root surface area density (RSD) and root length density (RLD) were significantly increased in the upper 10?60 cm soil layer under the RF and SC cultivation patterns during silking and maturity stages than that of TF planting under different N levels. However, among the different treatments, there was non-significant variation in RSD and RLD at below 70 cm soil profile. The RF2 and SC2 considerably increased the root dry weight, and the root bleeding sap during entire growth stages of maize crop than that of TF2 planting. The RF system with different N levels delayed roots senescence in the later growth

stage, and the production was significantly increased compared with SC and TF planting. Compared with SC2 and TF2 treatment, the RF2 treatment significantly increased the grain yield 5.7 t ha?1 (104%) and reduces root (79%) and stem (95%) lodging rate; therefore, RF2 cultivation method might be an appropriate water saving

approach in semi-arid regions.