Efficient Physiological and Nutrient Use Efficiency Responses of Maize Leaves to Drought Stress under Different Field Nitrogen Conditions

Abstract

Inadequate water and nitrogen (N) supplies can limit the productivity of maize. Climate change will likely increase drought in many regions on a global scale. The determination of N fertilizer rates under field drought conditions will be critical toward the reduction of agricultural risk. For this study, drought-resistant/sensitive cultivars were selected as experimental samples. Our results revealed that drought stress reduced the relative water content (RWC) of leaves, which resulted in leaf curling, while decreasing photosynthesis levels and N accumulation. In contrast to those without N treatments, the application of N significantly increased grain yields by 26.8% during the wet year but increased only by 5.4% during the dry year. Under the same N levels, the reduction in yield caused by drought increased with the increased application of N. This was because the application of the N fertilizer translated to increase the leaf area and transpiration, exacerbated the soil water loss and induced a leaf curling state in maize, which had deleterious effects on photosynthesis and N absorption. During the dry year, the yields of drought-sensitive cultivars were even less than those without the application of N. Compared with those of drought-sensitive cultivars, the RWCs of drought-resistant cultivars decreased more rapidly, and they entered the state of leaf curling earlier. Thus, N fertilizer inputs should be reduced, and the extent of N fertilization for drought-sensitive cultivars should be reduced even further.

The Contribution of Soil Tillage and Nitrogen Rate to the Quality of Maize Grain

“…The efficient agronomic management of N fertilisers is usually determined by other practices such as crop rotation, systems of soil tillage or irrigation, etc., and is also significantly related to the meteorological conditions of the year. According to results of Wang et al [43], the N application significantly increased maize grain yields by 26.8% during the wet year, but only increased yields by 5.4% during the dry year. It was obvious that higher fertiliser rates, for instance rates in the N3 treatment, expressed a positive impact on GY, together with the increase in the concentration of important grain components, such as proteins, carotenoids, GSH and Phy.…”

Integral effects of brassinosteroids and timber waste biochar enhances the drought tolerance capacity of wheat plant

“…For example, nitrogen use efficiency by wheat does not exceed 33% worldwide 28 and others nutrients mostly do not exceed 50%. Under drought conditions, nutrient use efficiency decreases considerably 31 and this may cause further reductions in plant productivity. In this investigation, we tested the feasibility of using the combined application of exogenous BR and BC as potential safe approaches to mitigate drought stress via increasing plant capability to utilize soil nutrients as well as the enzymatic and non-enzymatic antioxidants; hence this combined application might increase considerably crop yield productivity under drought conditions.…”

Optimized nitrogen fertilizer application strategies under supplementary irrigation improved winter wheat (Triticum aestivum L.) yield and grain protein yield

“…This results in excessive nitrogen fertilizer application in agricultural production ( Wu & Ma, 2015 ; Gao et al, 2020 ). In fact, excessive nitrogen application does not significantly improve the grain yield once the levels have exceeded the ability of plants to uptake nitrate, and instead the residual nitrogen fertilizer in the soil is lost via nitrate leaching and nitrous oxide emissions ( Wang et al, 2020 ). Therefore.…”