Highest Phosphorus Use Efficiency Research Articles

Identifying the critical phosphorus balance for optimizing phosphorus input and regulating soil phosphorus effectiveness in a typical winter wheat–summer maize rotation system in North China

Phosphorus (P) is a nonrenewable resource and a critical element for plant growth that plays an important role in improving crop yield. Excessive P fertilizer application is widespread in agricultural production, which not only wastes phosphate resources but also causes P accumulation and groundwater pollution. Here, we hypothesized that the apparent P balance of a crop system could be used as an indicator for identifying the critical P input in order to obtain a high yield with high phosphorus use efficiency (PUE). A 12-year field experiment with P fertilization rates of 0, 45, 90, 135, 180, and 225 kg P2O5 ha−1 was conducted to determine the crop yield, PUE, and soil Olsen-P value response to P balance, and to optimize the P input. Annual yield stagnation occurred when the P fertilizer application exceeded a certain level, and high yield and PUE levels were achieved with annual P fertilizer application rates of 90–135 kg P2O5 ha−1. A critical P balance range of 2.15–4.45 kg P ha−1 was recommended to achieve optimum yield with minimal environmental risk. The critical P input range estimated from the P balance was 95.7–101 kg P2O5 ha−1, which improved relative yield (>90%) and PUE (90.0–94.9%). In addition, the P input–output balance helps in assessing future changes in Olsen-P values, which increased by 4.07 mg kg−1 of P for every 100 kg of P surplus. Overall, the P balance can be used as a critical indicator for P management in agriculture, providing a robust reference for limiting P excess and developing a more productive, efficient and environmentally friendly P fertilizer management strategy.

Phosphorus responses of Trifolium pallescens and T. occidentale, the progenitors of white clover (T. repens)

Context Rock phosphate reserves are decreasing, and requirements to mitigate environmental impacts of farming soils with excess phosphorus (P) are increasing. Aims White clover is an allotetraploid hybrid between Trifolium pallescens and T. occidentale. Understanding the P response characteristics of these progenitor species will allow selection of germplasm for development of synthetic white clovers with improved phosphorus-use efficiency (PUE). Methods Shoot and root weights and P nutrition characteristics were compared for three Trifolium pallescens, six T. occidentale accessions, and a white clover cultivar in a glasshouse experiment using a low P soil amended with five rates of P. Key results White clover had the highest and most P responsive shoot and root dry weights (DW), and T. pallescens was least responsive to P. In the highest P treatment, T. pallescens had the highest shoot and root %P and the lowest shoot DW:total plant P ratio. There was significant variation among progenitor accessions. Spanish accessions of T. occidentale had comparable shoot DW to white clover and higher PUE. Traits of T. pallescens indicated strong adaptation to low P but low productivity, while traits of T. occidentale were more aligned with the white clover cultivar. Conclusions The substantial variation in P nutrition characteristics within the progenitor species of white clover could be exploited in breeding programs. Implications Comparing the P responses of a wider range of progenitor accessions could inform breeding to improve white clover’s low soil P tolerance through development of synthetic white clovers.

Nitrogen-inducible GLK1 modulates phosphate starvation response via the PHR1-dependent pathway.

Phosphorus (P) is a limiting nutrient for plant growth and productivity. Thus, a deep understanding of the molecular mechanisms of plants' response to phosphate starvation is significant when breeding crops with higher phosphorus-use efficiency. Here, we found that GARP-type transcription factor GLK1 acted as a positive regulator for phosphate-starvation response (PSR) via the PHR1-dependent pathway in Arabidopsis thaliana. GLK1 increased the transcription activity of PHR1 through the direct physical interaction and regulated the multiple responses to inorganic orthophosphate (Pi) starvation. Nitrogen (N) is a key factor in the regulation of PSR. We also found that the N status controlled the function of the GLK1-PHR1 signaling module under Pi-deficient (LP) conditions by regulating the accumulation of GLK1 and PHR1. Ultimately, we showed that the presence of GLK1 effectively promoted the protein accumulation of PHR1 at low N concentrations, and this action was helpful to maintain the activation of PSR. According to these findings, we establish the working model for GLK1 in PSR and propose that GLK1 mediates the interaction between N and P by influencing the effect of N on PHR1 in Arabidopsis thaliana.

Narrowing down molecular targets for improving phosphorus-use efficiency in maize (Zea mays L.).

Conventional agricultural practices rely heavily on chemical fertilizers to boost production. Among the fertilizers, phosphatic fertilizers are copiously used to ameliorate low-phosphate availability in the soil. However, phosphorus-use efficiency (PUE) for major cereals, including maize, is less than 30%; resulting in more than half of the applied phosphate being lost to the environment. Rock phosphate reserves are finite and predicted to exhaust in near future with the current rate of consumption. Thus, the dependence of modern agriculture on phosphatic fertilizers poses major food security and sustainability challenges. Strategies to optimize and improve PUE, like genetic interventions to develop high PUE cultivars, could have a major impact in this area. Here, we present the current understanding and recent advances in the biological phenomenon of phosphate uptake, translocation, and adaptive responses of plants under phosphate deficiency, with special reference to maize. Maize is one of the most important cereal crops that is cultivated globally under diverse agro-climatic conditions. It is an industrial, feed and food crop with multifarious uses and a fast-rising global demand and consumption. The interesting aspects of diversity in the root system architecture traits, the interplay between signaling pathways contributing to PUE, and an in-depth discussion on promising candidate genes for improving PUE in maize are elaborated.

Field pea (Pisum sativum L.) shows genetic variation in phosphorus use efficiency in different P environments

Field pea is important to agriculture as a nutritionally dense legume, able to fix nitrogen from the atmosphere and supply it back to the soil. However, field pea requires more phosphorus (P) than other crops. Identifying field pea cultivars with high phosphorus use efficiency (PUE) is highly desirable for organic pulse crop biofortification. This study identified field pea accessions with high PUE by determining (1) the variation in P remobilization rate, (2) correlations between P and phytic acid (PA), and (3) broad-sense heritability estimates of P concentrations. Fifty field pea accessions were grown in a completely randomized design in a greenhouse with two replicates under normal (7551 ppm) and reduced (4459 ppm) P fertilizer conditions and harvested at two time points (mid-pod and full-pod). P concentrations ranged from 332 to 9520 ppm under normal P and from 83 to 8473 ppm under reduced P conditions across all tissues and both time points. Field pea accessions showed variation in remobilization rates, with PI 125840 and PI 137119 increasing remobilization of P under normal P conditions. Field pea accessions PI 411142 and PI 413683 increased P remobilization under the reduced P treatment. No correlation was evident between tissue P concentration and seed PA concentration (8–61 ppm). Finally, seed P concentration under limited P conditions was highly heritable (H2 = 0.85), as was mid-pod lower leaf P concentrations under normal P conditions (H2 = 0.81). In conclusion, breeding for PUE in field pea is possible by selecting for higher P remobilization accessions in low P soils with genetic and location sourcing.

Tolerance to low phosphorus in rice varieties is conferred by regulation of root growth

Phosphorus use efficiency (PUE) can be improved through cultivation techniques and breeding. However, little is known about rice (Oryza sativa L.) agronomic and physiological traits associated with high PUE. We characterized the agronomic and physiological traits of rice varieties with different tolerances to low phosphorus in nutrient solution. Two varieties with strong tolerance to low phosphorus (STVs) and two with weak tolerance (WTVs) were grown at normal (NP, control) and low phosphorus (LP, 1/20 of NP) concentrations. Plants grown at LP produced significantly lower grain yield than those grown at NP. WTVs yields were lower than STVs yields. Compared to NP, LP significantly increased phosphorus translocation efficiency (PTE), internal phosphorus efficiency (IPE) and phosphorus harvest index (PHI). Under the LP condition, PTE and IPE were higher for STVs than for WTVs. LP also reduced tiller number, shoot biomass, leaf area index (LAI), leaf photosynthetic rate, and mean root diameter of both kinds of varieties at the main growth stages, but to a lower extent in STVs. LP significantly increased the number of productive tillers, root biomass, root-shoot ratio, root bleeding rate, and root acid phosphatase (RAP) activity. Total root length, root oxidation activity (ROA), and root total and active absorbing surface areas for STVs were significantly increased under LP, whereas the opposite responses were observed for WTVs. Total root length, ROA, root bleeding rate, root active absorbing surface area, and RAP activity were positively and significantly correlated with grain yield, PTE, and IPE. These results suggest that the tolerance of rice varieties to a low-phosphorus growth condition is closely associated with root growth with higher biomass and activity.

Translating phosphorus efficiency into effective fertilizer management

Phosphorus use efficiency (PUE) is frequently discussed as an indicator of crop productivity and environmental impact. However, to effectively capture both the agronomic and environmental benefits, we must look deeper into the science to understand which fertilizer practices should be adopted to maintain high PUE while supporting optimum yields and minimizing losses to water. Earn 0.5 CEUs in Nutrient Management by reading this article and taking the quiz at www.certifiedcropadviser.org/education/classroom/classes/622.

Adapting and evaluating APSIM-SoilP-Wheat model for response to phosphorus under rainfed conditions of Pakistan

Phosphorus (P) treatments were used to evaluate APSIM-SoilP-Wheat model and phosphorus use efficiency (PUE) of two wheat cultivars (NARC-2009 and Chakwal-50) during 2011–2013. Overall, the Agricultural Production Systems Simulator (APSIM) model accurately simulated dry matter, grains per spike, grain yield, biomass P, and grain P for two years, for both genotypes in response to all P fertilizer treatments. NARC-2009 had 55% higher PUE compared to Chakwal-50. Information on PUE will be helpful in breeding high PUE cultivars. Modeling results showed that the production of wheat depends on growth as well as on P uptake of the plants. The close agreement between observed and simulated results confirmed the accuracy of the model which was validated with skill scores like R2 and RMSE. APSIM simulation proved to be valuable tool to evaluate PUE under rainfed conditions.

Physiological and genetic analysis for maize root characters and yield in response to low phosphorus stress.

Root system architecture (RSA) plays an important role in the acquisition of mineral nutrients. Nevertheless, RSA has seldom been selected as an important agricultural trait in conventional breeding programs. Little is known about the response of RSA and phosphorus use efficiency (PUE) in regards to phosphorus (P) availability between parental inbred lines and their F1. In this study, 6 maize inbred lines and their 15 F1 generated by a diallel mating system, were used to analyze the genetic associations between RSA and PUE. Heterosis for PUE-related traits were comparatively greater under high P condition and reduced significantly under low P condition. Relative mid-parent heterosis for root traits were expressed more under the low P condition. Low P supply had a significant effect on heterosis, GCA and SCA of RSA- and PUE- related traits. The hybrid C3 (7922 × 8703-2), which had the highest PUE, showed an average yield with a lower P uptake under the both P conditions. Results from this study suggested breeding for a relatively high grain yield with reducing aboveground P demand and grain P concentration should be sufficient to reduce P fertilizer input and improve P efficiency.

Plant Growth Response of Eight Andean Dry Bean (<i>Phaseolus vulgaris </i>L.) Genotypes to Phosphorus Fertilizer in the Greenhouse

Common bean (Phaseolus vulgaris L.) is an important legume in the tropics, with production limited by low availability of soil phosphorus (P). An experiment was conducted in the glasshouse to evaluate P use efficiency of eight dry bean genotypes (G122, Montcalm, Taylor Horticulture, Cardinal, Bukoba, Kijivu, Rojo and CAL 143) of Andean origin. The treatments included: no P (0 kg P ha-1), normal P (50 kg P ha-1), and high P (100 kg P ha-1). There was variation for the measured traits shoot biomass (g), shoot P (mg kg-1), root P (mg kg-1), seed P (mg kg-1) and seed yield (g) among genotypes and P treatments. Biomass and all P concentrations increased with increasing P level and the genotypes Kijivu, Bukoba, Montcalm and Taylor Horticulture had higher P concentrations than Rojo, G122, Cardinal and CAL 143 across treatments. Genotype × treatment interactions were observed for shoot biomass. For the no P treatment, shoot and root biomass were positively correlated with PUE (phosphorus use efficiency). PUE had higher values and varied more among genotypes in the no P treatment compared to the normal P and high P treatments. The results suggest that seed yield in dry bean can be improved by selecting for genotypes with higher PUE under limiting P. The genotypes Bukoba, Kijivu and Montcalm with the highest values for PUE under no P treatment may be exhibiting some level of tolerance to low soil phosphorus. Higher shoot weight may provide simple criteria for selecting genotypes with greater yield and PUE (phosphorus use efficiency) under limiting P conditions. Therefore, a genotype is desired that can efficiently uptake and utilize available P under limited availability of this nutrient.

Roles, Regulation, and Agricultural Application of Plant Phosphate Transporters.

Phosphorus (P) is an essential mineral nutrient for plant growth and development. Low availability of inorganic phosphate (orthophosphate; Pi) in soil seriously restricts the crop production, while excessive fertilization has caused environmental pollution. Pi acquisition and homeostasis depend on transport processes controlled Pi transporters, which are grouped into five families so far: PHT1, PHT2, PHT3, PHT4, and PHT5. This review summarizes the current understanding on plant PHT families, including phylogenetic analysis, function, and regulation. The potential application of Pi transporters and the related regulatory factors for developing genetically modified crops with high phosphorus use efficiency (PUE) are also discussed in this review. At last, we provide some potential strategies for developing high PUE crops under salt or drought stress conditions, which can be valuable for improving crop yields challenged by global scarcity of water resources and increasing soil salinization.

Effects of nitrogen and phosphorus addition on leaf thermal tolerance in different provenances of Quercus variabilis

To explore potential effects of soil nutrient on leaf thermal tolerance across geographical origins, five provenance, i.e., Chengbu of Hunan (CB), Zigui of Hubei (ZG), Neixiang of Henan (NX), Lincheng of Heibei (LC) and Pinggu of Beijing (PG), seedlings of Quercus variabilis were cultivated under nitrogen and phosphorus addition. Leaf thermal tolerance parameters (cold, heat and span), nutrient concentrations (nitrogen and phosphorus), nitrogen use efficiency (NUE) and phosphorus use efficiency (PUE), as well as non-structural carbohydrate (soluble sugar and starch) concentrations were analyzed. The results were shown as follows: Nutrient absorption and utilization efficiency varied between oak origins with no obvious geographical trends. PG had higher nutrient use efficiency (NUE and PUE), whereas NX had lower PUE under all treatments. CB had the highest PUE under phosphorus addition. Compared with the control, nutrient addition increased the cold tolerance of PG and LC, and to some extent, increased the heat tolerance of the three middle provenances (ZG, NX, LC). However, the thermal span was opposite to the cold tolerance, as nutrient addition decreased the thermal span of PG and LC but increased that of NX. The leaf cold tolerance had significantly positive correlation with soluble sugar concentration, while the heat tolerance negatively and positively correlated with leaf phosphorus and ratio of nitrogen to phosphorus, respectively. No significant correlation was found between leaf thermal span and leaf chemical substances. To sum up, nutrient use efficiency varying in provenances might be contributed by the original habitats and consequently presented with some local adaptation characteristics, which complicated the response of thermal tolerance to nutrient addition.

Efficiency of Phosphorus Use for Dinitrogen Fixation Varies between Common Bean Genotypes under Phosphorus Limitation

Core Ideas Phosphorus use efficiency may be classified as trait for P‐deficiency tolerance. Low soil P availability is a limiting factor of the rhizobial symbiosis. The increase of P content may be involved in the regulation of nodulation. Low P availability in the soil is a major constraint to legume production, and efforts are being made to identify legume genotypes with tolerance to low P and greater phosphorus use efficiency (PUE) for N2 fixation. Common bean (Phaseolus vulgaris L.) genotypes vary in their adaptation to low‐P soils. To investigate to what extent this variation may be related to PUE for N2 fixation, six recombinant inbred lines (RILs) of common bean contrasting in PUE for symbiotic N2 fixation, namely RILs 147, 115, 104, 83, 34, and 29 were studied in the field conditions during four growing seasons from 2011 to 2015. We collected biomass (aboveground and belowground) at flowering stage, and both samples were analyzed P content. Results indicate that low‐P availability in the soil significantly limited plant growth, nodulation, and N2 fixation for all common bean RILs though with highest extent for common bean RILs 147, 83, and 29, whereas in this soil, common bean RILs 34 and 104 showed highest PUE for their N2 fixation. The genotypes with high PUE for N2 fixation showed greater mycorrhizal‐plant symbiosis activity rate than the genotypes with low PUE for N2 fixation. We also found a significant correlation between nodule biomass and nodule P content for all common bean RILs. We conclude that quantifying PUE for N2 fixation may contribute to characterize the level of adaptation of N2–fixing legumes to low‐P soils.

Genetic control of traits associated with phosphorus use efficiency in maize by REML/BLUP

The improvement phosphorus use efficiency (PUE) allows to reach satisfactory yields with lower costs. A breeding strategy for PUE is to increase its components, the phosphorus acquisiton efficiency (PAE) and phosphorus utilization efficiency (PUtE). Thus, this study aimed to identify: i) the relative importance of the components of PUE, in high and low phosphorus; ii) the relationship of root system length and shoot dry mass (SDM) with PUE and its components and; iii) the genetic control of traits associated with the PUE. Forty-one hybrid combinations were evaluated in two experimental environments representing contrasting conditions of availability of phosphorus: low (LP) and high (HP). A randomized block design with two replications were used in simple factorial (hybrid combination x availability of phosphorus) arrangement. Independently of phosphorus availability, PAE was the most important component of the PUE and non-additive genetic effects were more important to the traits associated with the PUE. It was observed that the estimates of specific combining ability for SDM and PUE, in LP and HP, showed similar behavior and magnitude, indicating that the selection based on performance of hybrid combinations for SDM, allows to obtain genotypes with high PUE.

English

A field trial was conducted in 2008 at the Institute for Agricultural Research farm at Samaru, to evaluate the phosphorus uptake, phosphorus use efficiency (PUE) and yield potentials, of five groundnut (Arachis hypogaea L.) genotypes (SAMNUT 10, 11, 21, 22 and 23). Four levels of phosphorus (0, 20, 40 and 60 kg P2O5 ha-1) were applied to each genotype in a randomized complete block design (RCBD ) with three replications. In addition to PUE indices, haulms and pod yields were also recorded. Among the genotypes evaluated, SAMNUT 23 recorded the highest total P uptake of 68.96 mg P kg-1 while SAMNUT 10 recorded the least (44.22 mg P kg-1). SAMNUT 23 also produced the highest (2,298 kg ha-1) dry pod yield. The highest PUE of 71.71 and 64.53% were recorded by SAMNUT 10 and 21 respectively, while SAMNUT 23 recorded the least (31.46%) PUE. The early or medium, maturing genotypes, SAMNUT 21 and 22, were observed to be better than both the extra-early, SAMNUT 23, and late-maturing SAMNUT 10 and 11, in terms of dry haulms yield. Therefore, SAMNUT 10 and 21 had greater adaptation for low soil P conditions than the other genotypes, and hence more suitable to resource-poor farmers. Key words: Groundnut genotypes, phosphorus, phosphorus use efficiency.

Influence of Arbuscular Mycorrhizae Indigenous to Peru and a Flavonoid on Growth, Yield, and Leaf Elemental Concentration of `Yungay' Potatoes

The influence of arbuscular mycorrhizal fungi (AMF) [two Peruvian mixed isolates, a pure isolate of Glomus intraradices] and the flavonoid, formononetin, were tested on growth, yield, and leaf elemental concentration of the Peruvian potato (Solanum tuberosum L.) `Yungay'. Plants started from tissue culture-produced prenuclear minitubers of `Yungay' were subjected to seven treatments, which included noncolonized (non-AMF) plants fertilized with Long Ashton nutrient solution modified to supply P at 11 and 44 μg·mL-1. All AMF plants received low P (11 μg·mL-1) and were inoculated with either a sierra-maize mixed isolate, sierra-papa mixed isolate, pure isolate of G. intraradices, sierra-maize mixed isolate + formononetin, or a sierra-papa mixed isolate + formononetin. Plants were grown in 3-L containers under shade house conditions in Lima, Peru. Non-AMF plants at low P had the poorest growth, while high P plants had the greatest overall growth. All AMF plants had greater growth, including a higher root to shoot ratio, higher phosphorus use efficiency [(g tuber)/(g P/kg tissue)], and a lower leaf to tuber ratio (indicating greater leaf efficiency in producing tuber dry matter), compared to non-AMF plants at low P. The mycorrhizal inoculation effect (MIE) ranged from +44% to +57%, indicating that `Yungay' was moderately to highly mycorrhizal dependent. Plants colonized with the sierra-papa isolate + formononetin had the same tuber development and leaf to tuber ratio, compared to high P, non-AMF plants. Formononetin increased extraradical hyphae formation. Mycorrhizal enhancement was in part due to greater P, Fe, and Mg uptake, a higher phosphorus-use efficiency and greater extraradical hyphae formation.

Effect of irrigation scheduling and fertigation on nutrient and water-use efficiency in drip-irrigated direct-seeded rice (Oryza sativa)

A field experiment was conducted during the rainy (kharif) seasons of 2016 and 2017 at Gangavathi, Raichur, Karnataka, to study the effect of irrigation scheduling and fertigation on nitrogen and water-use efficiency of drip-ir- rigated direct-seeded rice (Oryza sativa L.) in clay soil. The experiment laid out in split-plot design with 4 irrigation scheduling based on irrigation water : cumulative pan evaporation (IW : CPE) ratios assigned to main plots and 4 drip fertigation levels were allocated in subplots and replicated thrice. Irrigation scheduling at an IW : CPE ratio of 1.50 recorded significantly higher nutrient-use efficiency, viz. nitrogen (35.2 kg/kg), phosphorus (85.4 kg/kg) and potassium (102.5 kg/kg) and but lower water-use efficiency (7.69 kg/ha-mm) and water productivity (0.61 kg/m3). Among the drip fertigation levels, drip fertigation at 75% recommended dose of nitrogen (RDN) recorded higher ni- trogen-use efficiency (41.5 kg/kg). Treatment of 125% RDN resulted in higher phosphorus-use efficiency and po- tassium-use efficiency (84.1 and 101.0%, respectively) and water-use efficiency and water productivity (7.22 kg/ ha-mm and 0.59 kg/m3 respectively).

Performance of Acacia Tortilis, Prosopis Juliflora and Casuarina Equisetifolia Provenances in Soils Low in Phosphorus

AbstractAcacia tortilis, Prosopis juliflora and Casuarina equisetifolia provenances were screened to determine their potential for adaptability under P limiting conditions as a strategy to exploit genotypic differences in terms of utilization and uptake efficiencies. The experiment was conducted in the greenhouse at the Kenya Forestry Research Institute using soils taken from the field which are critically low in available phosphorus (P). The experimental treatments comprised of P application at 0 and 60 Kg P205/ha for 11 provenances of Acacia, 6 Prosopis and 4 Casuarina spp. Trait for adaptability to P deficiency was determined by measuring the growth performance, P uptake and utilization efficiencies at zero and moderate application of P. The results indicated considerable differences in the growth performance and Phosphorus use efficiency (PUE). Acacia provenances showed the highest PUE compared with Prosopis and Casuarina spp although “this was not reflected in the total dry matter yield. However, it ...

Responses to Phosphorus of Contrasting Successional Tree-Seedling Species from the Tropical Deciduous Forest of Mexico

1. We compared the growth responses of three early successional species, Cochlospermum vitifolium, Cordia alliodora and Heliocarpus pallidus, and the late successional Caesalpinia eriostachys, Caesalpinia platyloba, Jacquinia pungens and Recchia mexicana tree-seedling species to four concentrations (0, 2, 10 and 41 ppm) of phosphorus. The experiment was conducted over 50 days in pure silica sand inside growth chambers. 2. Mature-forest species had low relative growth rates and net assimilation rates, and showed little or no response, in growth and biomass allocation, to different P concentrations. 3. Early successional species had small seeds and higher responses in biomass allocation, growth and net assimilation rates to P availability, as well as a higher phosphorususe efficiency when P supply was low. 4. Species and treatment differences in growth rate generally corresponded more closely with patterns of net assimilation rate than with biomass allocation. The responsiveness of growth to P availability was negatively correlated with seed mass and P dependency.