Relationship between four inorganic phosphorous forms with regards to maize p uptake in two soils of south-western Nigeria

Rumen ciliates still have mysterious secrets and influences in ruminants. This study investigated the effect of transfaunation of pure and mixed cultures of rumen ciliates on physical clinical examination, selected serum parameters and milk profile in defaunated lactating dairy goats. A number of 8 Baladi native breed goats were randomly classified into two groups each one containing 4 goats. Pure culture group was transfaunated with 6 ml of pure culture of Holotricha spp., while mixed culture group was transfaunated with 6 ml of mixed culture of 81.85% Holotricha and 18.15% Ophryoscolex spp. once weekly for three consecutive weeks, after defaunation of both groups using 30 ml of 8% SLS for two consecutive days. Serum and milk samples were collected weekly for three successive weeks to study effect of type of ciliate culture, duration of transfaunation and their interaction. Results revealed that transfaunation of pure and mixed cultures of rumen ciliates had no effect on physical examination with minimal non-significant improvement of calcium, inorganic phosphorous, total protein and globulin in serum of defaunated goats. Transfaunation of pure or mixed cultures of rumen ciliates within three weeks could not improve significantly decreased milk fat % of defaunated goats without any effect on other measured milk profile parameters. It is concluded that further investigations on transfaunation without prior defaunation should be performed using different pure and mixed cultures of rumen ciliates for therapeutic and productive purposes.

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Model based evaluation of plant improvement strategies for biological nutrient removal

Water Science & Technology ◽

10.2166/wst.1999.0188 ◽

1999 ◽

Vol 39 (4) ◽

pp. 45-53 ◽

Cited By ~ 1

Author(s):

H. M. van Veldhuizen ◽

M. C. M. van Loosdrecht ◽

F. A. Brandse

Keyword(s):

Activated Sludge ◽

Wastewater Treatment Plants ◽

P Uptake ◽

Biological Nutrient Removal ◽

Adequate Description ◽

Control Scheme ◽

Detailed Simulation ◽

High Fraction ◽

Biokinetic Parameters ◽

P Removal

An activated sludge model for biological N- and P-removal was developed, which describes anoxic and aerobic P-uptake based on bacterial metabolism. This model was tested in practice on two wastewater treatment plants, which are BCFS®-processes, which contain activated sludge with a high fraction of denitrifying P-removing bacteria (DPB's). The model appeared to be able to give an adequate description of the performance of these treatment plants under different conditions. If the process parameters are well defined almost no calibration of the biokinetic parameters was necessary. In the simulation of Dalfsen wwtp, which has a complex control scheme, it was possible to give an adequate simulation of the control actions and the concentration profiles in a rather simple way, showing that detailed simulation of these controllers was not necessary. With the calibrated model it was possible to analyse bottlenecks and give suggestions for upgrading of the concerned treatments plants. The simulation results were used in decisions on investments.

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SPX-related genes regulate phosphorus homeostasis in the marine phytoplankton, Phaeodactylum tricornutum

Communications Biology ◽

10.1038/s42003-021-02284-x ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Kaidian Zhang ◽

Zhi Zhou ◽

Jiashun Li ◽

Jingtian Wang ◽

Liying Yu ◽

...

Keyword(s):

Stress Responses ◽

Phaeodactylum Tricornutum ◽

Response Regulator ◽

P Uptake ◽

Negative Regulator ◽

Marine Phytoplankton ◽

Alkaline Phosphatases ◽

Phosphate Starvation Response ◽

Essential Nutrient ◽

Global Oceans

AbstractPhosphorus (P) is an essential nutrient for marine phytoplankton. Maintaining intracellular P homeostasis against environmental P variability is critical for phytoplankton, but how they achieve this is poorly understood. Here we identify a SPX gene and investigate its role in Phaeodactylum tricornutum. SPX knockout led to significant increases in the expression of phosphate transporters, alkaline phosphatases (the P acquisition machinery) and phospholipid hydrolases (a mechanism to reduce P demand). These demonstrate that SPX is a negative regulator of both P uptake and P-stress responses. Furthermore, we show that SPX regulation of P uptake and metabolism involves a phosphate starvation response regulator (PHR) as an intermediate. Additionally, we find the SPX related genes exist and operate across the phytoplankton phylogenetic spectrum and in the global oceans, indicating its universal importance in marine phytoplankton. This study lays a foundation for better understanding phytoplankton adaptation to P variability in the future changing oceans.

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Sex-specifically responsive strategies to phosphorus availability combined with different soil nitrogen forms in dioecious Populus cathayana

Journal of Plant Ecology ◽

10.1093/jpe/rtab025 ◽

2021 ◽

Author(s):

Xiucheng Liu ◽

Yuting Wang ◽

Shuangri Liu ◽

Miao Liu

Keyword(s):

Root Length ◽

Root Length Density ◽

Specific Root Length ◽

P Uptake ◽

Root Tip ◽

P Availability ◽

P Deficiency ◽

Populus Cathayana ◽

Leaf P ◽

P Supply

Abstract Aims Phosphorus (P) availability and efficiency are especially important for plant growth and productivity. However, the sex-specific P acquisition and utilization strategies of dioecious plant species under different N forms are not clear. Methods This study investigated the responsive mechanisms of dioecious Populus cathayana females and males based on P uptake and allocation to soil P supply under N deficiency, nitrate (NO3 −) and ammonium (NH4 +) supply. Important Findings Females had a greater biomass, root length density (RLD), specific root length (SRL) and shoot P concentration than males under normal P availability with two N supplies. NH4 + supply led to higher total root length, RLD and SRL but lower root tip number than NO3 − supply under normal P supply. Under P deficiency, males showed a smaller root system but greater photosynthetic P availability and higher leaf P remobilization, exhibiting a better capacity to adaptation to P-deficiency than females. Under P deficiency, NO3 − supply increased leaf photosynthesis and PUE but reduced RLD and SRL in females while males had higher leaf P redistribution and photosynthetic PUE than NH4 + supply. Females had a better potentiality to cope with P deficiency under NO3 − supply than NH4 + supply; the contrary was true for males. These results suggest that females may devote to increase in P uptake and shoot P allocation under normal P availability, especially under NO3 − supply, while males adopt more efficient resource use and P remobilization to maximum their tolerance to P-deficiency.

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Dynamics of fractionated rhizosphere soil P and plant P uptake under maize/P-mobilizing legumes intercropping in strongly weathered soil of Tanzania

Soil Science & Plant Nutrition ◽

10.1080/00380768.2021.1911589 ◽

2021 ◽

pp. 1-11

Author(s):

Soh Sugihara ◽

Tomomi Kawashita ◽

Mawazo Shitindi ◽

Boniface Massawe ◽

Haruo Tanaka

Keyword(s):

Rhizosphere Soil ◽

P Uptake ◽

Soil P ◽

Weathered Soil ◽

Plant P Uptake

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Impact of Mycorrhization on Phosphorus Utilization Efficiency of Acacia gummifera and Retama monosperma under Salt Stress

Forests ◽

10.3390/f12050611 ◽

2021 ◽

Vol 12 (5) ◽

pp. 611

Author(s):

Abdessamad Fakhech ◽

Martin Jemo ◽

Najat Manaut ◽

Lahcen Ouahmane ◽

Mohamed Hafidi

Keyword(s):

Salt Stress ◽

Root Growth ◽

N Uptake ◽

P Uptake ◽

Utilization Efficiency ◽

Legume Species ◽

Growth Responses ◽

Phosphorus Utilization ◽

Phosphorus Utilization Efficiency ◽

Shoot And Root Growth

The impact of salt stress on the growth and phosphorus utilization efficiency (PUE) of two leguminous species: Retama monosperma and Acacia gummifera was studied. The effectiveness of arbuscular mycorrhizal fungi (AMF) to mitigate salt stress was furthermore assessed. Growth, N and P tissue concentrations, mycorrhizal root colonization frequency and intensity, and P utilization efficiency (PUE) in the absence or presence of AMF were evaluated under no salt (0 mM L−1) and three salt (NaCl) concentrations of (25, 50 and 100 mM L−1) using a natural sterilized soil. A significant difference in mycorrhizal colonization intensity, root-to-shoot ratio, P uptake, PUE, and N uptake was observed between the legume species. Salt stress inhibited the shoot and root growth, and reduced P and N uptake by the legume species. Mycorrhizal inoculation aided to mitigate the effects of salt stress with an average increase of shoot and root growth responses by 35% and 32% in the inoculated than in the non-inoculated A. gummifera treatments. The average shoot and root growth responses were 37% and 45% higher in the inoculated compared to the non-inoculated treatments of R. monosperma. Average mycorrhizal shoot and root P uptake responses were 66% and 68% under A. gummifera, and 40% and 95% under R. monosperma, respectively. Mycorrhizal inoculated treatments consistently maintained lower PUE in the roots. The results provide insights for further investigations on the AMF conferred mechanisms to salt stress tolerance response by A. gummifera and R. monosperma, to enable the development of effective technologies for sustainable afforestation and reforestation programs in the Atlantic coast of Morocco.

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Synergy between a shallow root system with a DRO1 homologue and localized P application improves P uptake of lowland rice

Scientific Reports ◽

10.1038/s41598-021-89129-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Aung Zaw Oo ◽

Yasuhiro Tsujimoto ◽

Mana Mukai ◽

Tomohiro Nishigaki ◽

Toshiyuki Takai ◽

...

Keyword(s):

Root System ◽

Crop Production ◽

Soil Surface ◽

P Uptake ◽

Ore Deposits ◽

Root Surface Area ◽

Genetic Traits ◽

P Use Efficiency ◽

Use Efficiency ◽

P Application

AbstractImproved phosphorus (P) use efficiency for crop production is needed, given the depletion of phosphorus ore deposits, and increasing ecological concerns about its excessive use. Root system architecture (RSA) is important in efficiently capturing immobile P in soils, while agronomically, localized P application near the roots is a potential approach to address this issue. However, the interaction between genetic traits of RSA and localized P application has been little understood. Near-isogenic lines (NILs) and their parent of rice (qsor1-NIL, Dro1-NIL, and IR64, with shallow, deep, and intermediate root growth angles (RGA), respectively) were grown in flooded pots after placing P near the roots at transplanting (P-dipping). The experiment identified that the P-dipping created an available P hotspot at the plant base of the soil surface layer where the qsor1-NIL had the greatest root biomass and root surface area despite no genotyipic differences in total values, whereby the qsor1-NIL had significantly greater biomass and P uptake than the other genotypes in the P-dipping. The superior surface root development of qsor1-NIL could have facilitated P uptakes from the P hotspot, implying that P-use efficiency in crop production can be further increased by combining genetic traits of RSA and localized P application.

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Genetic Dissection of Phosphorous Uptake and Utilization Efficiency Traits Using GWAS in Mungbean

Agronomy ◽

10.3390/agronomy11071401 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1401

Author(s):

Venkata Ravi Prakash Reddy ◽

Shouvik Das ◽

Harsh Kumar Dikshit ◽

Gyan Prakash Mishra ◽

Muraleedhar S. Aski ◽

...

Keyword(s):

Genome Wide Association Study ◽

Genotyping By Sequencing ◽

Dry Weight ◽

P Uptake ◽

Utilization Efficiency ◽

Genetic Dissection ◽

P Deficiency ◽

P Utilization ◽

P Utilization Efficiency ◽

Phosphorous Uptake

Mungbean (Vignaradiata L. Wilczek) is an early maturing legume grown predominantly in Asia for its protein-rich seeds. P deficiency can lead to several physiological disorders which ultimately result in a low grain yield in mungbean. The genetic dissection of PUpE (Puptake efficiency) and PUtE (P utilization efficiency) traits are essential for breeding mungbean varieties with a high P uptake and utilization efficiency. The study involves an association mapping panel consisting of 120 mungbean genotypes which were phenotyped for total dry weight, P concentration, total P uptake, and P utilization efficiency under low P (LP) and normal P (NP) conditions in a hydroponic system. A genotyping-by-sequencing (GBS) based genome-wide association study (GWAS) approach was employed to dissect the complexity of PUpE and PUtE traits at the genetic level in mungbean. This has identified 116 SNPs in 61 protein-coding genes and of these, 16 have been found to enhance phosphorous uptake and utilization efficiency in mungbeans. We identified six genes with a high expression (VRADI01G04370, VRADI05G20860, VRADI06G12490, VRADI08G20910, VRADI08G00070 and VRADI09G09030) in root, shoot apical meristem and leaf, indicating their role in the regulation of P uptake and utilization efficiency in mungbean. The SNPs present in three genes have also been validated using a Sanger sequencing approach.

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