Quantitative Evaluation Of The Fertility Of Tropical Soils Model Research Articles

QUEFTS Model-based Estimation of the Nutrient Requirements and Fertilizer Recommendation for Chinese Onion

Accurate estimation of the nutrient requirements of Chinese onion is essential to increase its nutrient utilization efficiency and yield. In this study, the yield and nutrient uptake data were collected from major Chinese onion growing regions during 2001 to 2018, and the relationship between Chinese onion yield and nutrient uptake was evaluated using the Quantitative Evaluation of the Fertility of Tropical Soils (QUEFTS) model. The QUEFTS model predicted the linear-parabolic platform curve of the balanced nutrient uptake of Chinese onion and estimated the demand of nitrogen (N), phosphorus (P), and potassium (K) for the potential target yields ranging from 40 t/ha to 120 t/ha. The nutrients required for the target yield increased linearly before reaching 60% to 70% of the potential yield. Nutrient requirements for producing 1 t of Chinese onion were 1.91 kg N–0.28 kg P–1.71 kg K. The corresponding nutrient internal efficiency (IE, yield per unit nutrient uptake) was 524.6 kg/kg, 3585.7 kg/kg, and 584.3 kg/kg for N, P and K, respectively. Subsequently, a nutrition decision-making software, Nutrient Expert (NE), for the Chinese onion was developed based on the improved QUEFTS model. Field verification studies for NE fertilizer recommendation were conducted in multiple Chinese onion growing plots for 2 consecutive years. Results showed that the QUEFTS model can be used to accurately estimate the nutrient requirements for Chinese onion within a defined range of target yield.

Genotypic Variation in Nutrient Uptake Requirements of Rice Using the QUEFTS Model

Nutrient requirements for single-season rice using the quantitative evaluation of the fertility of tropical soils (QUEFTS) model in China have been estimated in a previous study, which involved all the rice varieties; however, it is unclear whether a similar result can be obtained for different rice varieties. In this study, data were collected from field experiments conducted from 2016 to 2019 in Zhejiang Province, China. The dataset was separated into two parts: japonica/indica hybrid rice and japonica rice. To produce 1000 kg of grain, 13.5 kg N, 3.6 kg P, and 20.4 kg K were required in the above-ground plant dry matter for japonica/indica hybrid rice, and the corresponding internal efficiencies (IEs) were 74.0 kg grain per kg N, 279.1 kg grain per kg P, and 49.1 kg grain per kg K. For japonica rice, 17.6 kg N, 4.1 kg P, and 23.0 kg K were required to produce 1000 kg of grain, and the corresponding IEs were 56.8 kg grain per kg N, 244.6 kg grain per kg P, and 43.5 kg grain per kg K. Field validation experiments indicated that the QUEFTS model could be used to estimate nutrient uptake of different rice varieties. We suggest that variety should be taken into consideration when estimating nutrient uptake for rice using the QUEFTS model, which would improve this model.

Temporal variation in nutrient requirements of tea (Camellia sinensis) in China based on QUEFTS analysis

Fertilisation datasets collected from field experiments (n = 21) in tea-producing areas from 2016 to 2018 were used to build a quantitative evaluation of the fertility of tropical soils (QUEFTS) model to estimate nutrient uptake of tea plants, and to investigate relationships between tea yield and nutrient accumulation. The production of 1000 kg spring tea (based on one bud with two young expanding leaves) required 12.2 kg nitrogen (N), 1.2 kg phosphorus (P), and 3.9 kg potassium (K), and the corresponding internal efficiencies (IEs) for N, P, and K were 82.0, 833.3, and 256.4 kg kg−1. To produce 1000 kg summer tea, 9.1 kg N, 0.8 kg P, and 3.1 kg K were required, and the corresponding IEs for N, P, and K were 109.9, 1250.0, and 322.6 kg kg−1. For autumn tea, 8.8 kg N, 1.0 kg P, and 3.2 kg K were required to produce 1000 kg tea, and the corresponding IEs for N, P, and K were 113.6, 1000.0, and 312.5 kg kg−1. Field validation experiments performed in 2019 suggested that the QUEFTS model can appropriately estimate nutrient uptake of tea plants at a certain yield and contribute to developing a fertiliser recommendation strategy for tea production.

Estimating Nutrient Uptake Requirements for Potatoes Based on QUEFTS Analysis in China

Excessive or imbalanced fertilization has not only decreased nutrient use efficiency, but also degraded arable land and posed a great threat to the environment. In this study, the datasets were collected from field experiments for the period 1992 to 2017 in the main potato (Solanum tuberosum L.) production regions of China. We used the Quantitative Evaluation of the Fertility of Tropical Soils (QUEFTS) model to estimate the soil‐plant balanced N, P, and K requirements for the potato in China. Our results revealed that there were great differences in the potato yield and nutrient uptake. The upper and lower 2.5th percentiles of N, P, and K internal efficiencies (IE, kg tuber per kg nutrient in the total plant) data were used as maximum accumulation (a) and maximum dilution (d) boundary parameters in the QUEFTS model, which were 133 and 463 kg kg–1 for N, 652 and 3030 kg kg–1 for P, and 119 and 790 kg kg–1 for K, respectively. The QUEFTS model predicted plant nutrient uptake of 4.0 kg N, 0.7 kg P, and 3.5 kg K to produce 1 Mg of tuber in the linearly distributed portion, and a corresponding tuber nutrient demand of 2.9 kg N, 0.5 kg P, and 2.3 kg K to produce 1 Mg of tuber. Field validation experiments confirmed that the QUEFTS model could be used to simulate optimum nutrient uptake and provide appropriate parameters in building fertilizer recommendation, which helps improve nutrient use efficiency for potato in China.Core Ideas This is the first report of QUEFTS model on estimating the optimum nutrient requirements for potato crops in China. The datasets used in this study were collected from multi‐year‐site field experiments. Multi‐site field validation experiments in potato‐producing areas confirmed the feasibility of QUEFTS model‐simulated nutrient uptake.

Estimating nutrient uptake requirements for radish in China based on QUEFTS model

Imbalanced fertilization has caused lower yield and nutrient use efficiency for radish (Raphanus sativus L.) production in China. Estimating nutrient requirements for radish is crucial in optimizing fertilization to resolve the problem. On-farm experiments in the radish-growing regions of China from 2000 to 2017 were collected to investigate the relationship between fleshy root yield and nutrient accumulation in radish plant using the Quantitative Evaluation of the Fertility of Tropical Soils (QUEFTS) model. The QUEFTS model predicted a linear increase in fleshy root yield if nutrients were taken up in balanced amounts until yield reached about 60%–70% of the potential yield. The balanced N, P, and K requirements in radish plant simulated by the QUEFTS model were 2.15, 0.45, and 2.58 kg to produce 1000 kg of fleshy root, and the corresponding internal efficiencies (IEs, kg fleshy root per kg nutrient in total plant dry matter) for N, P, and K were 465.1, 2222.2, and 387.1 kg kg−1. The simulated balanced N, P, and K removal by fleshy root to produce 1000 kg fleshy root were 1.34, 0.30, and 1.93 kg, respectively. Approximately 62%, 67%, and 75% of N, P, and K in radish plant were presented in the fleshy root and removed from the soil. Field validation experiments confirmed the consistency between the observed and simulated nutrient uptake values. The QUEFTS model was proven to be effective for estimating nutrient requirements of radish and will contribute to develop fertilizer recommendations for radish cultivated in China.

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

The balance between fertilizer application and plant nutrient demand is essential for ensuring agricultural production because it is effective to prevent nutrient deficiency and excess, especially for soybean. This study used data from 29 sites of field experiments carried out in the soybean planting area of Liaoning province, China in 2011 to 2013. We (i) study the characteristics of yield, nutrient concentration, and harvest index to (ii) valuate the balanced nutrient uptake at different potential yield levels for soybean. The grain yield ranged from 804 to 4484 kg/ha, and average N, P, and K concentrations in grains were 45.7, 5.0, and 10.1 g/kg, respectively, while those in straw were 14.1, 1.8, and 6.7 g/kg, respectively. Average harvest index values of N, P, and K were 0.69, 0.65, and 0.52 kg/kg, respectively, while approximately 69% N and 65% P of the plant were stored in soybean grain, and 48% K was stored in straw. The two boundary lines of the QUEFTS (quantitative evaluation of the fertility of tropical soils) model were aN = 10.5, dN = 20.6, aP = 65.6, dP = 289.6, aK = 30.4, and dK = 162.7 as model parameters. The QUEFTS model estimated the balanced nutrient uptake with yield targets increased following a linear–parabolic–plateau curve. A continual linear increase in grain yield with 65.5 kg N, 7.0 kg P, and 13.9 kg K was required to produce 1000 kg grain, until the yield target reached approximately 60–70% of the potential yield, and the corresponding ratio of N, P, and K was 9.35:1:1.8. Results could be used to estimate balanced nutrient uptake to prevent excessive fertilizer being applied and reduce environment risk for ensuring sustainable agricultural development.

Estimating nutrient uptake requirements for soybean using QUEFTS model in China.

Estimating balanced nutrient requirements for soybean (Glycine max [L.] Merr) in China is essential for identifying optimal fertilizer application regimes to increase soybean yield and nutrient use efficiency. We collected datasets from field experiments in major soybean planting regions of China between 2001 and 2015 to assess the relationship between soybean seed yield and nutrient uptake, and to estimate nitrogen (N), phosphorus (P), and potassium (K) requirements for a target yield of soybean using the quantitative evaluation of the fertility of tropical soils (QUEFTS) model. The QUEFTS model predicted a linear–parabolic–plateau curve for the balanced nutrient uptake with a target yield increased from 3.0 to 6.0 t ha−1 and the linear part was continuing until the yield reached about 60–70% of the potential yield. To produce 1000 kg seed of soybean in China, 55.4 kg N, 7.9 kg P, and 20.1 kg K (N:P:K = 7:1:2.5) were required in the above-ground parts, and the corresponding internal efficiencies (IE, kg seed yield per kg nutrient uptake) were 18.1, 126.6, and 49.8 kg seed per kg N, P, and K, respectively. The QUEFTS model also simulated that a balanced N, P, and K removal by seed which were 48.3, 5.9, and 12.2 kg per 1000 kg seed, respectively, accounting for 87.1%, 74.1%, and 60.8% of the total above-ground parts, respectively. These results were conducive to make fertilizer recommendations that improve the seed yield of soybean and avoid excessive or deficient nutrient supplies. Field validation indicated that the QUEFTS model could be used to estimate nutrient requirements which help develop fertilizer recommendations for soybean.

Estimating nutrient uptake requirements for rice in China

Accurate knowledge of the nitrogen (N), phosphorus (P), and potassium (K) requirements for rice (Oryza sativa L.) in China is essential to quantitatively estimate optimal fertilizer application regimes to maximize crop yield and increase nutrient use efficiency. On-farm experiments were collected in China's major rice-producing regions from 2000 to 2013, to determine the relationship between grain yield and nutrient uptake in the above-ground plant dry matter using the quantitative evaluation of the fertility of tropical soils (QUEFTS) model. The large datasets obtained which covered broader rice growing areas and ecology types (both indica and japonica) in China. The dataset was divided into two groups: single-season rice and early/middle/late rice, according to QUEFTS analysis. The QUEFTS model predicted a linear increase in grain yield if nutrients were taken up in balanced amounts until yield reached about 60–70% of yield potential. To produce 1000kg of single-season rice grain, 14.8kgN, 3.8kg P, and 15.0kgK were required in the above-ground plant dry matter, and the corresponding internal efficiencies (IEs) were 67.6kg grain per kg N, 263.2kg grain per kg P, and 66.7kg grain per kg K. For early/middle/late rice, the amount of 17.1kgN, 3.4kgP, and 18.4kgK were required in the above-ground plant dry matter to produce 1000kg of grain, and corresponding IEs were 58.5kg grain per kgN, 294.1kg grain per kgP, and 54.3kg grain per kgK. The QUEFTS model provides a scientific foundation for filtering high-yielding and high-efficiency variety, optimizing fertilizer application rate and developing nutrient management strategies to increase yield and nutrient use efficiency. This is the first report on comparison of the nutrient uptake of different ecology types in rice production area of China using QUEFTS model and test their feasibility through field validation.

Estimating nutrient requirements for winter oilseed rape based on QUEFTS analysis

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.

Nutrient requirements for maize in China based on QUEFTS analysis

Estimating balanced nutrient requirements for maize (Zea mays L.) in China is essential to manage nutrient application more effectively for increasing crop yield and reducing the risk of negative environmental impact. On-farm datasets were collected from 2001 to 2010 from China's maize-producing regions to investigate the relationship between grain yield and nutrient accumulation in the above-ground plant dry matter of commercial hybrid maize. The QUEFTS (quantitative evaluation of the fertility of tropical soils) model was used to estimate the balanced nitrogen (N), phosphorus (P) and potassium (K) requirements in China's maize growing regions. The analysis indicated that there were great differences in the grain yield and nutrient uptake between spring maize and summer maize: minimum and maximum internal nutrient efficiencies (IE, kg grain per kg nutrient in the above-ground plant dry matter) were 36 and 89kg grain per kg N, 135 and 558kg grain per kg P, 30 and 132kg grain per kg K for spring maize, 31 and 70kg grain per kg N, 108 and 435kg grain per kg P, 32 and 110kg grain per kg K for summer maize. The model predicted a linear increase in grain yield if nutrients were taken up in balance until yield reached about 60–70% of the potential yield. To produce 1000kg of spring maize grain yield, 16.9kgN, 3.5kgP and 15.3kgK were required by above-ground dry matter of maize, and the corresponding IE were 59kg grain per kg N, 287kg grain per kg P and 65kg grain per kg K. For summer maize, 20.3kgN, 4.4kgP, 15.9kgK were needed to produce 1000kg maize grain in the linear part, and the corresponding IE were 49kg grain per kg N, 227kg grain per kg P and 63kg grain per kg K. Optimal N:P:K ratios in plant biomass were 4.83:1:4.37 for spring maize and 4.61:1:3.61 for summer maize, respectively. QUEFTS analysis also indicated that a balanced N, P and K removal by grain to produce 1000kg grain, when the target yield reached about 80% of the potential yield, the grain absorption of N, P and K accounted for 54%, 69% and 23% of above-ground N, P and K uptake for spring maize, and 67%, 85% and 23% for summer maize, respectively. Two-year field validation experiments indicated that the QUEFTS model could be used for estimating balanced nutrient requirements and contributed to developing fertilizer recommendations.