Estimating nutrient requirements for winter oilseed rape based on QUEFTS analysis

Abstract

SUMMARYEstimating crop nutrient requirements for winter oilseed rape (Brassica napus L.) is a crucial step in optimizing fertilization to enhance seed yield and improve fertilizer use efficiency. In the present paper, a database composed of 1035 on-farm observations collected from 2005 to 2010 across the major winter oilseed rape production regions in China was used to evaluate internal nutrient efficiencies (kg seed per kg nutrient in plant dry matter); then the Quantitative Evaluation of the Fertility of Tropical Soils (QUEFTS) model for winter oilseed rape was developed to describe the nutrient uptake-yield relationship of oilseed rape over a wide range of environmental conditions and predict the nutrient requirements for a target yield. After excluding observations with low harvest index values, <0·20, and excluding 0·025 of the highest and lowest internal nutrient efficiencies, the minimum and maximum internal nutrient efficiencies were estimated as 13·1 and 31·6 kg seed/kg nitrogen (N), 68·9 and 200·3 kg seed/kg phosphorus (P) and 8·9 and 31·1 kg seed/kg potassium (K), respectively. On the basis of the data settings, the balanced N, P and K uptake at different yield potential levels was calculated using a linear–parabolic–plateau curve with the QUEFTS model. Crop nutrient requirements increased linearly until the yield reached approximately 0·60–0·70 of the potential yield, and 46·0 kg N, 8·0 kg P and 57·1 kg K were found to be needed to produce 1000 kg of seed. The corresponding internal nutrient efficiencies were 21·8, 125·1 and 17·5 kg seed/kg N, P and K, respectively. However, when the target yields approached the yield potential, a decrease in internal nutrient efficiencies was detected in the model. The predicted nutrient requirement values simulated by the QUEFTS model compared well with observed values across a range of conditions. To conclude, the QUEFTS model was shown to be a practical and robust tool for assessing the crop nutrient requirements of winter oilseed rape.

Leaf photosynthetic capacity is regulated by the interaction of nitrogen and potassium through coordination of CO2 diffusion and carboxylation

“…Oilseed rape is a predominant edible oil source worldwide, with an increasing demand on a global scale (Foley et al , Tilman et al ). Although N and K uptake by oilseed rape is relatively large, with a ratio of 1:1.24 (Kullmann et al , Ren et al ), potassium fertilizer application currently receives little attention. In the Yangtze River basin, with the largest winter oilseed rape production region in world, the N and K fertilizer input ratio is 1:0.25 (unpublished data), and unbalanced N and K fertilization severely restricts rapeseed yield potential.…”

P and K Accumulation by Rapeseed as Affected by Biostimulant under Different NPK and S Fertilization Doses

“…When plants were well fertilized, with an additional uptake stimulation coming from biostimulant application, the nutrients accumulation in the plant increased; but, the increase in yield was not proportional. According to Ren et al [34], P and K uptake by rapeseed increases linearly until the yield reaches 0.6-0.7 of the potential yield. However, when the target yield approaches the yield potential, a decrease in IE is detected.…”

“…Internal nutrient efficiency (IE) (kg kg −1 ) is the seed yield divided by nutrient accumulation in the above-ground part. Reciprocal internal nutrient efficiency (RIE) (kg 1000 kg −1 ) is the nutrient uptake in above-ground part divided by seed yield ×1000 [34,35].…”

Characteristics of Yield and Harvest Index, and Evaluation of Balanced Nutrient Uptake of Soybean in Northeast China

“…In this research, we simulated the balanced nutrient uptake for yield potential following Ren et al [17] and Chuan et al [18]. The key procedures of the QUEFTS model included:…”

“…The QUEFTS model as an effective tool for quantitating nutrient balances with optimal fertilizer management. The QUEFTS model is a practical approach that has been widely and successfully implemented in diverse crops, such as rice [15,16], maize [12], oilseed rape [17], and wheat [18,19]. Recently, a study on the balanced nutrient uptake of soybean applied by the QUEFTS model in China was published by Yang et al [5]; the studies considered large experimental regions.…”