Amount Of Available Nutrients Research Articles

Organic Materials Promote Rhododendron simsii Growth and Rhizosphere Soil Properties in a Lead-Zinc Mining Wasteland.

The mining of metal minerals generates considerable mining wasteland areas, which are characterized by poor soil properties that hinder plant growth. In this study, a field plot experiment was carried out in the mining wasteland of the Lanping lead-zinc mine in Yunnan Province to study the effects of applying three organic materials-biochar (B), organic fertilizer (OF), and sludge (S)-at concentrations of 1% (mass fraction), on promoting the soil of mining wasteland and the growth of two plant varieties (Huolieniao and Yingshanhong). The results showed that the amount of available nutrients in the surface soil of a mining wasteland could be considerably increased by S and OF compared to the control check (CK). In the rhizosphere soils of two Rhododendron simsii varieties, the application of S increased the available phosphorus (P) content by 66.4% to 108.8% and the alkali-hydrolyzed nitrogen (N) content by 61.7% to 295.5%. However, the contents of available cadmium (Cd) and available lead (Pb) were reduced by 17.1% to 32.0% and 14.8% to 19.0%, respectively. Moreover, three organic materials increased the photosynthetic rate and biomass of two R. simsii varieties. Specifically, OF and S were found to significantly increase the biomass of R. simsii. Organic materials have direct impacts on the increased plant height and biomass of R. simsii. Additionally, organic materials indirectly contribute to the growth of R. simsii by reducing the content of available Cd and available Pb in rhizosphere soil while increasing the content of available nutrients according to the structural equation model (SEM). Overall, S can stabilize Cd and Pb, increase soil nutrient contents, and promote the growth of R. simsii effectively, and has great potential in the vegetation reconstruction of mining wasteland.

Integrated Nutrient Management Fostered Economic Yield and Bioactive Principle of Medicinal Herb (Cassia angustifolia Vahl.) in Saline Soil of Semi-Arid Region of Western India

ABSTRACT In this investigation, cultivation of an economically important medicinal plant (Senna, Cassia angustifolia Vahl.) was explored in saline soil for improving productivity and quality through effective nutrient management practices. Field experiments were conducted in two consecutive growing seasons in saline soils of semi-arid region, where recommended dose fertilizer (RDF) supplied through organic (vermicompost) and inorganic (chemical) source alone or in combination with local microbial consortia (MC). Plant growth and nutrition significantly improved due to integration of organic and inorganic fertilizer alone or in combination with MC. The results also reflected in economic yield (leaf + pod) of senna where 29–37% increase in leaf and 57–76% increase in pod yield was recorded over control. The results revealed that integration of organic and chemical fertilizer along with MC recorded significant higher leaf (1682 kg ha−1) and pod (488 kg ha−1) yield as compared to the other treatment. Sennocide content in leaf and pod was significantly improved by organic as well as integrated application of organic and inorganic fertilizer. However, the highest sennocide content in leaf (2.81%) and pod (3.11%) was recorded in integrated application of organic fertilizer and MC. Additionally, integrated application of organic and chemical fertilizer was found effective in restoring organic carbon, increasing the amount of available nutrients (N, P, and K), and enhancing the biological activity of the saline soil. Therefore, integration of organic and chemical fertilizer as well as MC has potential to improve yield and quality of senna through enhanced soil fertility and biological function.

The DELTA Model: Understanding the Ability of the Global Food System to Deliver Nutrition

ObjectivesWhile the environmental, social and economic sustainability of the current global food system attracts increasing research, its ability to nourish the global population must be prioritised. Our objective was to produce a computational model illustrating the nutritional adequacy of the current global food system and allow investigation of proposed global food system scenarios. MethodsData from several public databases was collected to describe food production, processing and waste in the global food system. Data was also sourced for global demographics and human nutritional requirements for 29 nutrients. These data were used to construct the DELTA Model. The model takes global food production scenarios as its input and calculates the nutrients available for human consumption, after consideration of animal feed uses, waste and non-food use. This amount of available nutrients was then compared to demographically weighted target daily intakes, allowing the nutritional adequacy of the food system to be quantified. The DELTA Model also includes nutrient bioavailability adjustments for protein and essential amino acids to ensure accurate conclusions are drawn for these nutrients, demonstrated to be pressure points in global nutrition previously. The model is freely available online. ResultsModelling the 2018 global food system showed that neither energy nor protein are limiting under conditions of equal food distribution, even with a population increase of 1 billion. Halving food waste between farm and consumer allows for sufficient energy and protein availability to nourish the forecast 2050 population of 9.7 billion using current production volumes. However, numerous micronutrient insufficiencies emerge in these future scenarios. Considering the bioavailability of protein and amino acids reduced the availability of these nutrients by between 2% and 17% compared to simply considering the content of foods, emphasizing the importance of this consideration. ConclusionsIt is essential that nutritional adequacy is at the forefront of the sustainable food system debate. The DELTA Model allows both experts and non-experts to better understand food system dynamics in global nutrition, aiding the discussion of what changes to the food system may be appropriate. Funding SourcesFunding from the Riddet Institute Centre of Research Excellence.

Productivity, nutrients uptake and quality of forage oat (Avena sativa) and residual soil fertility as influenced by nitrogen and FYM

A field experiment was conducted during rabi season (2014-16) at Research Farm, R.B.S. College, Bichpuri, Agra (U.P.) to study the effect of nitrogen and FYM levels on growth, yield and uptake of nutrients in oat (Avena sativa L.) and soil fertility. The experiment was laid out in randomized block design with four levels of nitrogen (0,50,100 and 150 kg ha-1) and three levels of FYM (0, 5 and 10 t ha-1) with three replications. The results revealed that the plant height, yields of oat crop increased significantly up to 150 kg N and 10 t FYM ha-1 over control. The maximum values of green foliage (447.16 and 414,03 qha-1) and dry matter yield (64.98 and 60.30 q ha-1) were recorded with 150 kg N and 10 t FYM ha-1 , respectively. The application of FYM alone was also found to be more beneficial in terms of growth and yield of oat crop over control. The interaction effect between 150 kg N ha-1 and 10 t FYM ha-1 recorded maximum yield than other treatment combination. The maximum content (14.14 and 14.10 %) and yield of protein in oat crop (920.6 and 853.5 kg ha-1) were recorded with 150 kg N and 10 t FYM ha-1 but maximum value of crude fiber (32.96 and 33.7 %) were recorded under control, respectively. However, crude fiber content in oat was not affected significantly with N and FYM levels. The uptake of major (N,P and K) and micronutrients (Fe,Mn,Cu and Zn) by oat crop increased significantly with the levels of nitrogen up to 150 kg ha-1 and FYM 10 t ha-1, respectively. The status of organic carbon and available nutrients in post harvest soil improved with 150 kg N and 10 t FYM ha-1.The minimum amounts of available nutrients in post harvest soil were recorded under control treatment.

Influence of Animal Manures on Carbon Mineralisation and Nutrient Availability in Calcareous Soil

Many studies were reported the impact of manure addition in enhancing soil fertility. However, animal manures might have different effects on calcareous soils. The effect of two different animal manure on carbon mineralisation and macronutrient availability in calcareous soils was studied. Different rates of poultry manure (PM5= 5 g kg-1, and PM10= 10 g kg-1 soil), cattle manure (CM5= 5 g kg-1 and CM10= 10 g kg-1 soil), and an equal mixture of the two animal manures (PCM5= 5 g kg-1, and PCM10= 10 g kg-1 soil) was investigated for 90 days. Animal manures increased CO2–C respiration rate and cumulative CO2-C in soils compared to untreated soils, and the highest results were observed in treatments that received 10 g kg-1 soil manure (PM10, PCM10 and CM10). The addition of animal manures increased available N, P, and K compared to untreated soils. Furthermore, treatments that received poultry manure alone (PM5, PM10) or in combination with cattle manure (PCM5, PCM10) contained a greater amount of available nutrients (N, P and K) when compared to soils treated with cattle manure at the same addition rate. Overall, the addition of poultry and cattle manures to calcareous soil has positive effects on macronutrient availability and carbon mineralisation.

Effects of wood resource size and decomposition on hyphal outgrowth of a cord-forming basidiomycete, Phanerochaete velutina

To assess the relationship between resource use and hyphal growth in a cord-forming basidiomycete, Phanerochaete velutina, soil microcosm experiments were conducted using wood blocks of three different sizes in three different soil quantities, thereby simulating the different amounts of available nutrients. The highest percentage weight loss was observed in the smallest wood blocks after a 27-d incubation period in soil microcosms, although the percentage weight loss over the 2-month pure culture colonization prior to inoculation was not significantly different among various block sizes. The greatest hyphal outgrowth was also observed in the smallest wood blocks and was positively associated with wood decay. The slopes of the regression lines between hyphal coverage and percentage wood mass loss were identical among different wood sizes, but the slopes between hyphal coverage and absolute wood mass loss were steeper in the smaller wood blocks than that in largest one. These results suggest that the level of intensity of mycelial foraging for new resources in the soil depends on the percentage of the amount of wood resource utilized, and not on the absolute amount of carbon obtained from the wood.

Planosol CO2 Respiration, Chemical and Physical Properties of Differently Tilled Faba Bean Cultivation

Soil tillage intensity influences the chemical composition of soil, the distribution of nutrients, and soil physical and mechanical properties, as well as gas flows. The impact of reduced tillage on these indices in faba bean cultivation is still insufficient and requires more analysis on a global scale. This study was carried out at Vytautas Magnus University, Agriculture Academy (Lithuania) in 2016–2018. The aim of the investigation was to establish the influence of the tillage systems on the soil chemical composition, temperature, moisture content, and CO2 respiration in faba bean cultivation limited by the semi-humid subarctic climate. On the basis of a long-term tillage experiment, five tillage systems were tested: deep and shallow moldboard plowing, deep cultivation-chiseling, shallow cultivation-disking, and no-tillage. Results showed that in conditions of plowless tillage systems, the content of precrops’ residues on the topsoil before the spring tillage was 5 to 15 times higher than in plowed plots. It undoubtedly was for the amount of available nutrients in the soil, soil temperature, and moisture content. Plowless and no-tillage systems could initiate an increase in the amount of available nutrients in soil. The highest concentration of chemical elements was found in no-tilled plots. So faba bean crops could largely increase the composition of potassium and total nitrogen and stabilized CO2 respiration from soil during one vegetative period.

Proteínas trasportadoras de fósforo de la familia PHT1 y su uso potencial en la agricultura moderna

La agricultura se ha globalizado por sus modernos avances orientados a producir más y mejores alimentos bajo un modelo de protección ambiental. Esta práctica se realiza en suelos con diferentes cantidades de nutrientes disponibles y se basa en el uso de fuentes minerales externas para satisfacer la demanda del cultivo. El fósforo (P) es un macroelemento que participa en funciones vitales de las plantas como la producción de adenosín trifosfato (ATP), formación de biomembranas y reacciones de señalización, entre otras. Las plantas utilizan estrategias fisio-morfológicas ante una deficiencia de P que se manifiestan en síntomas característicos como desarrollo deficiente, elongación de raíz, maduración precoz y reducción de la productividad del cultivo como consecuencia. Para mantener la homeostasis celular, las plantas inducen la sobreproducción de proteínas de membrana con función transportadoras de fosfato en los diferentes órganos. Estas proteínas pertenecen a la familia PHT1, presentan un transporte de tipo sin porte que facilita la introducción de fosfato inorgánico (Pi) desde la rizosfera y permiten satisfacer la demanda biológica durante los procesos de señalización y energía. Estructuralmente estas proteínas son altamente conservadas en plantas (monocotiledóneas y dicotiledóneas) y se caracterizan por poseer 12 dominios transmembranales, un dominio conservado 2A0109 y tamaño aproximado de 520 aa. El objetivo de la presente revisión es situar en perspectiva el conocimiento actual de las proteínas transportadoras de fosfato PHT1, tomando de base los avances en modelos biológicos para mejorar los procesos productivos y las técnicas de manejo nutricional en los cultivos.

Effect of integrated nutrient management on wheat (Triticum aestivum) yield, nutrient uptake and soil fertility status in alluvial soil

A field experiment was conducted on alluvial soil at SVP University of Agriculture and Technology Meerut (UP) during winter (rabi) season of 2013-14 and 2014-15 to study the effect of integrated nutrient management (INM) on yield, nutrient uptake of wheat (Triticum aestivum L.) and soil fertility. The experiment was laid-out in a randomized complete block design with 9 treatments and 3 replicates. The results revealed that plant height, tillers/m, spike length, grains/spike test weight, and grain and straw yields increased significantly over control due to fertilizer application. The grain (5 t/ha) and straw (6.88 t/ha) yields at 100% NPK were 79.7 and 78.2% higher than the control. The yield of wheat was improved further with conjoint application of 75% NPK + organic manures (OM). The maximum values of growth, yield attributes and grain (5.39 t/ha) and straw yield (7.33 t /ha) were recorded with 75% NPK + 5 t FYM + 2.5 t VC/ha closely followed by 75% NPK + 2.5 t VC + 3.75 t press mud (PM)/ha. Application of VC and FYM was found to be more beneficial in terms of growth and yield of wheat. The uptake of N, P, K, S, and Zn by wheat crop was highest at 75% NPK + 5 t FYM + 2.5 t VC/ha and lowest in control. The use of organic manures decreased soil pH and their combined use with fertilizers was significantly reflected in the buildup of organic C, available N, P, K, S and DTPA-extractable Zn content of the post-harvest soils. The minimum amount of available nutrients in post-harvest soil was recorded under control.

Metabolic Switch in the Tumor Microenvironment Determines Immune Responses to Anti-cancer Therapy.

Tumor-induced immune tolerance permits growth and spread of malignant cells. Cancer cells have strong influence on surrounding cells and shape the hypoxic tumor microenvironment (TME) facilitating cancer progression. A dynamic change in glucose metabolism occurring in cancer cells and its influence on the TME are still poorly understood. Indeed, cancer and/or immune cells undergo rapid adaptation in metabolic pathways during cancer progression. Metabolic reprograming affects macrophages, T cells, and myeloid derived suppressor cells (MDSCs) among other immune cells. Their role in the TME depends on a nature and concentration of factors, such as cytokines, reactive oxygen species (ROS), growth factors, and most importantly, diffusible metabolites (i.e., lactate). Further, the amounts of available nutrients and oxygen as well as activity of microbiota may influence metabolic pathways in the TME. The roles of metabolites in regulating of the interaction between immune and cancer cell are highlighted in this review. Targeting metabolic reprogramming or signaling pathways controlling cell metabolism in the TME might be a potential strategy for anti-cancer therapy alone or in combination with current immunotherapies.

Drainage and fertilization effects on nutrient availability in an ombrotrophic peatland

Nutrient availability is an important control on the vegetation distribution, productivity and functioning of peatland ecosystems and we examined spatial and temporal patterns of nutrient availability through ion exchange at Mer Bleue bog, southeast Ontario, Canada. We installed ion exchange probes at 5–15cm for 4weeks and determined nutrient sorption at undisturbed sites as well as those affected by nitrogen (N), phosphorus (P), potassium (K) fertilization and drainage. Under undisturbed conditions, the bog had very small amount of available nutrients, especially N (ammonium>nitrate) and P, and exhibited small variations in nutrient availability during the growing season (May to October). The increase in NPK availability upon fertilization was short-lived over the season and the stoichiometry of available NPK captured by the probes was mismatched with the vegetation. The increase in nutrient availability with drainage was confounded by substantial changes in vegetation. We compare these results with data from other Canadian bogs and fens to provide baseline data on nutrient availability in peatlands.

Salmonella enterica Serovar Typhimurium Strategies for Host Adaptation.

Bacterial pathogens must sense and respond to newly encountered host environments to regulate the expression of critical virulence factors that allow for niche adaptation and successful colonization. Among bacterial pathogens, non-typhoidal serovars of Salmonella enterica, such as serovar Typhimurium (S. Tm), are a primary cause of foodborne illnesses that lead to hospitalizations and deaths worldwide. S. Tm causes acute inflammatory diarrhea that can progress to invasive systemic disease in susceptible patients. The gastrointestinal tract and intramacrophage environments are two critically important niches during S. Tm infection, and each presents unique challenges to limit S. Tm growth. The intestinal tract is home to billions of commensal microbes, termed the microbiota, which limits the amount of available nutrients for invading pathogens such as S. Tm. Therefore, S. Tm encodes strategies to manipulate the commensal population and side-step this nutritional competition. During subsequent stages of disease, S. Tm resists host immune cell mechanisms of killing. Host cells use antimicrobial peptides, acidification of vacuoles, and nutrient limitation to kill phagocytosed microbes, and yet S. Tm is able to subvert these defense systems. In this review, we discuss recently described molecular mechanisms that S. Tm uses to outcompete the resident microbiota within the gastrointestinal tract. S. Tm directly eliminates close competitors via bacterial cell-to-cell contact as well as by stimulating a host immune response to eliminate specific members of the microbiota. Additionally, S. Tm tightly regulates the expression of key virulence factors that enable S. Tm to withstand host immune defenses within macrophages. Additionally, we highlight the chemical and physical signals that S. Tm senses as cues to adapt to each of these environments. These strategies ultimately allow S. Tm to successfully adapt to these two disparate host environments. It is critical to better understand bacterial adaptation strategies because disruption of these pathways and mechanisms, especially those shared by multiple pathogens, may provide novel therapeutic intervention strategies.

Effect of conjoint use of farmyard manure and fertilizers on yield and nutrient uptake by onion (Allium cepa) and soil fertility

Field experiment was conducted for two consecutive rabi seasons (2010-11 and 2011-12) at the Research farm, R B S College, Bichpuri, Agra (Uttar Pradesh) to study the effect of conjoint use of FYM and chemical fertilizers on yield and nutrients uptake by onion (Allium cepa L.) and soil fertility. The experiment was laid out in randomized block design with twelve treatments and three replications. The results revealed that the scale leaves/bulb and fresh weight of onion bulb and bulb yields increased significantly up to 150% NPK level over control. The yields of onion bulbs were significantly lower with the sub-optimal dose of NPK fertilizers. All the parameters further increased when 10 tonnes FYM/ha was added along with 100% NPK. An additional bulb yield of 3.35 tonnes/ha was realized with 100 % NPK + 10 tonnes/ha over 100% NPK alone. Application of 100% NPK + 5 kg Zn +1 kg B/ ha produced 32.13 tonnes/ha bulbs and dry matter yield (5.03 tonnes/ha) of onion which was superior to 100 % NPK alone (30.36and 4.75 tonnes/ha). The maximum protein content (5.75 %) and yield (29.75 q/ha) were obtained with 150% NPK and 100% NPK + 10 tonnes FYM/ha, respectively. The uptake of N, P, K, S, Zn and B by the onion bulbs was found to be associated with production of dry matter resulted by the addition of 100% NPK + 10 t FYM/ha. However, the maximum uptake of Zn (281.0 g/ha) and B (392.1 g/ha) by onion bulbs was noted under 100% NPK+5 kg Zn/haand 100% NPK + 1 kg B/ha, respectively. The conjoint use of 10 t FYM/ha with 100 % NPK significantly improved the status of available N, P, K, S, Zn and B in post harvest soil over the NPK fertilizers alone. Available B and Zn contents were found to be higher in treatment combination of 100% NPK + 1 kg B /ha and 100 % NPK + 5 kg Zn/ha, respectively. The minimum amounts of available nutrients in post harvest soil were recorded under control treatment.

Utilization of Coal Bottom Ash and Cattle Manure as Soil Ameliorant on Acid Soil and Its Effect on Heavy Metal Content in Mustard (Brassica juncea)

Coal bottom ash and cattle manure can be used as soil ameliorant. The application of coal bottom ash and cattle manure can improve the soil chemical properties, such as pH and the amounts of available nutrients in soil. The objective of the study was to understand the effect of coal bottom ash and cow manure application on soil chemical properties and heavy metal contents in soil and mustard (Brassica juncea). A pot experiment was conducted in a greenhouse, including three treatment factors, i.e. age of coal bottom ash (fresh, 4 months and 2 years), dose of coal bottom ash, i.e. 0, 40 and 80 Mg ha-1, and dose of cattle manure, i.e. 0 and 10 Mg ha-1. The results show that the application of coal bottom ash and cattle manure increased the pH and the amounts of total-N, available-P and exchangeable cations (K, Ca and Mg) of the soil. The application of coal bottom ash increased the amounts of Pb, Cd and Co in the soil, but did not increase the amounts of Pb and Co in mustard, while the application of cattle manure increased the amount of Cd both in soil and mustard. Keywords: Coal bottom ash, cattle manure, heavy metal, mustard, soil ameliorant

Time-lapse effect of ancient plant coal biochar on some soil agrochemical parameters and soil characteristics.

Biochar is a solid material obtained from reductive, oxygen-free processes, i.e. the thermo-chemical conversion of biomass in oxygen-limited environment. The obtained products have high carbon sequestration potential and strong nutrient-water absorption capacities because of the enlarged carbon surfaces. It is not yet clear how carbon stimulates agrochemical parameters in soil and how those characteristics are developing as time goes on a long-term basis. Samples of ancient (25, 35, 80years old) plant coal-affected soils were collected in a temperate deciduous forest site located in the south part of the Bükk Mountains (in North Eastern Hungary). Physical-chemical soil characteristics, such as soil pH, cation exchange capacity (CEC), the organic and inorganic nitrogen (NH4+, NH3-) and the available nutrients (P2O5 and K2O), were estimated beside organic matter (SOM) content, measured by two different methods. Levels of polycyclic aromatic hydrocarbon (PAH) compounds in soil and in various biochar samples were assessed in relation with permissible limit values and potential toxicity. Positive correlation was found between the amount of available nutrients, total organic nitrogen content, cation exchange capacity and the age of plant coal-affected soils. The sample soils were exposed to continuous plant coal biochar effect for 25years, during which macronutrients absorbed and accumulated in the plant coal surfaces. After this period, the degradation of carbon developed simultaneously with the reduction of the amount of available nutrients, till the end of the studied 80-year-affecting period. Measured CEC level indicated positive correlation with nutrient availability and the age of biochar-affected soils. Our results support the hypothesis that biochar in soil can improve its general agrochemical characteristics in relation with its persistence in a specific soil-plant system. Potential PAH content and toxicity of biochar products are key issues of developing proper application rates in sustainable agricultural practices.

Nutrient restriction and realimentation in beef cows during early and mid-gestation and maternal and fetal hepatic and small intestinal in vitro oxygen consumption

Objectives were to determine the effects of advancing gestation, maternal nutrient restriction during early and mid-gestation, and realimentation on fetal liver and jejunal mass and energy use in both dams and fetuses. On day 30 of pregnancy, multiparous, non-lactating beef cows (initial BW=621±11.3 kg and body condition score=5.1±0.1) were assigned to one of the two dietary treatments: control (CON; 100% requirements; n=18) and restricted (R; 60% requirements; n=28). On day 85, cows were slaughtered (CON, n=6; R, n=6), and remaining cows continued on control (CC; n=12) and restricted (RR; n=12) diets, or were realimented to the control diet (RC; n=11). On day 140, cows were slaughtered (CC, n=6; RR, n=6; RC, n=5), remaining cows continued on the control diet (CCC, n=6; RCC, n=5), or were realimented to the control diet (RRC, n=6). On day 254, all remaining cows were slaughtered. Maternal liver O2 consumption linearly increased (P⩽0.04) and jejunal weight (g/kg) linearly decreased (P=0.04) as gestation advanced in CON groups. Fetal BW, and hepatic and small intestinal absolute mass, protein content and O2 consumption linearly increased (P⩽0.04) as pregnancy advanced in CON groups. However, mass and O2 consumption relative to BW linearly decreased (P⩽0.001) in the fetal liver in CON groups. When analyzing the effects of dietary treatment, at day 85, fetal jejunal O2 consumption (mol/min per kg BW) was lower (P=0.02) in the R group when compared with the CON group. At day 140, maternal hepatic weight (g) was lower (P=0.02) in RC and RR cows when compared with CC, and fetal jejunual O2 consumption (mmol/min per mg tissue and mmol/min per g protein) was greater (P⩽0.02) in RC when compared with RR. At day 254, maternal hepatic O2 consumption (absolute and relative to BW) was lower (P⩽0.04) in the RCC cows when compared with RRC. Fetal hepatic weight was lower (P=0.05) in the CCC group when compared with RCC and RRC. The changes in response to nutrient restriction and realimentation in both the dam and fetus may indicate an adaptation to a lower amount of available nutrients by altering tissue mass and metabolism.

Corrections for rooting volume and plant size reveal negative effects of neighbour presence on root allocation in pea

Summary Plants are able to detect the presence of their neighbours below‐ground. The associated root responses may affect plant performance, plant–plant interactions and community dynamics, but the extent and direction of these responses is heavily debated. Some studies suggest that plants will over‐proliferate roots in response to neighbours at the expense of reproduction, which was framed as a ‘tragedy of the commons’. Others propose an ‘ideal free distribution’ hypothesis stating that plants produce roots simply as a function of the amount of available nutrients. However, experimental evidence for either hypothesis that is unbiased by confounding effects of rooting volume and plant size in their experimental set‐ups is still lacking. We grew split‐root pea plants in the presence or absence of a below‐ground neighbour at a range of rooting volumes, while providing equal amounts of nutrients per plant. Path analyses were used to disentangle the direct effects of neighbour presence on allocation patterns from the confounding effects of rooting volume and plant size. Within the chosen range of rooting volumes, the presence of a below‐ground neighbour generally reduced plant root mass by 21% and total mass by 9%. A doubling of rooting volume generally increased plant root mass by 22% and total mass by 11%. Pod mass was only directly and positively correlated with vegetative mass. The presence of a below‐ground neighbour induced less root allocation but more pod allocation, whereas increased rooting volume caused a reduction in reproductive allocation. A large part of these effects, however, was indirectly mediated through the influence on plant total mass. Synthesis. Not considering the effects of rooting volume and plant size may lead to misinterpretations of plant growth strategies in response to neighbours. Accounting for these factors, we found pea allocating less mass to roots in the presence of a below‐ground neighbour. The obtained results can help to reconcile the various responses to below‐ground neighbours as they are published in the literature.

PO-0856 Ketogenic Diet And Tuberous Sclerosis: A Romance?

Introduction Brain injuries of tuberous sclerosis have a particularly severe clinical appearance because they are providers of heavy effects and can be life-threatening We present a special scheme that was believed, wrongly, archaic effect. Material and methods A young infant is followed since the age of 9 months for TS with refractory epilepsy and autism, without parenchymal CNS tumour. After many therapies, a ketogenic diet is proposed... The suites are fantastic: 1 single seizure after one year of follow-up (4 years old) and decreased aggressiveness of the patient Result and discussion Tuberous sclerosis (TS) is a phacomatosis due to mutations in tumour suppressor genes (TSC1 and TSC2). Epilepsy can be the first clinical sign and occur at any age : 60–90% of TS patients have epilepsy. The earliest type and the most characteristic is the West syndrome. Current research indicates that mTOR integrates information from multiple signalling pathways, including insulin, growth factors (such as IGF-1 and IGF- 2) and mitogens. mTOR is also an indicator of the amount of available nutrients for the cell, as well as the energy and redox status. Thus, the continuous decrease of nutrient inputs inhibits sensible cell receptor of the mTOR pathway and induces a suppressive response with an inverse pathophysiological mechanism. Conclusion Although ancient, the ketogenic diet has been updated, especially in support of the TS; thanks to genetic advances, noting the crucial role of nutritional receptors by inactivating the mTOR pathway.

Treating fermentative residues as liquid fertilizer and its efficacy on the tomato growth

Considering the rapid development of bioconversion techniques, recycling organic wastes from fermentation processes for agricultural production and soil restoration is a new field. Chemical and biological analyses indicated that the liquid residue (LR) from lipopeptide biosurfactants production contained large amount of available nutrients and free amino acids, and minimal content of heavy metals and showed low phytotoxicity. The greenhouse experiments showed that 1.0%(v/w) of LR to pot soil was the best proportion for its application as liquid fertilizer with an enhancement of plant height, shoot dry weight root length, root diameter and root dry weight by 67.18, 285.62, 122.26, 13.04 and 204.55%, respectively. The bacteria counts, enzyme activities and available nutrients in rhizosphere soil increased significantly with the increasing rates of LR. LR had better promoting effects on plant growth and soil quality in comparison with chemical fertilizer at the same NPK levels. Our results suggested an effective way to use residues from biosurfactants fermentation at large.

茅苍术叶片可培养内生细菌多样性及其促生潜力

Atractylodes lancea is a medicinal plant grown in Jiangsu Province,China.The diversity of the endophytic bacteria culturable from the leaves of A.lancea and their plant growth-promoting potential,including nitrogen fixation,phosphorus solubilization,potassium solubilization and indole acetic acid(IAA) production were investigated.According to morphological characteristics of bacterial colonies,52 endophytic bacterial strains were obtained and 45 could be subcultured normally in vitro and subjected to amplified ribosomal DNA restriction analysis(ARDRA).Based on the ARDRA fingerprints,the 45 subculturable endophytic bacterial strains could be classified into 14 clusters.The 16S rDNA fragments of representative strains from different clusters were sequenced and deduced by a BLAST search to identify similar strains.The results showed that the isolated endophytic bacteria most likely belong to Pantoea sp.,Microbacterium sp.,Curtobacterium sp.,Agrobacterium sp.,Pseudomonas sp.,or Bacillus sp.Among them,the Pseudomonas sp.was the most dominant genera.BOX-PCR was then used to study the diversity of the endophytic bacteria in the main ARDRA clusters.The BOX-PCR fingerprints showed that the endophytic bacteria in the same cluster were not similar,indicating a broad genetic diversity within the same genera.Ten of the 45 subculturable endophytic bacteria could grow normally on Burk′s medium,which indicates their potential to fix nitrogen.We also amplified the nifH genes in these strains and all strains generated a band of the expected size except for ALEB 33.Among all subculturable endophytic bacteria,19 and 15 strains could dissolve insoluble calcium phosphate and lecithin,respectively,and then release dissociative phosphorus into the medium.ALEB 43 could dissolve the largest amount of phosphorous from calcium phosphate,reaching(251.43±6.55) mg/L.Furthermore,ALEB 4A could dissolve the largest amount of phosphorous from lecithin,reaching(23.63±1.46) mg/L.After comparing the amount of phosphorous dissolved from calcium phosphate by the endophytic bacteria and the pH of the bacterial inoculum,we deduced that some phosphate-solubilizing bacteria dissolve insoluble calcium phosphate by secreting certain types of acids.However,the pH of the fermentation solution of endophytic bacteria capable of dissolving lecithin was not related to the release of dissociative phosphorus.There were 24 strains that could grow on silicate medium,indicating these strains had the potential to dissolve insoluble potassium feldspar and release dissociative potassium,which was available to plants.Forty three endophytic bacterial strains could produce and release IAA into the medium.The amount of IAA released by ALEB 44 was the highest,reaching(268.44±10.12) μg/mL.These endophytic bacteria could promote the growth of host plants by increasing the amounts of available nutrients or phytohormones.This paper is the first to reveal the diversity of endophytic bacteria in A.lancea and their plant growth-promoting potential.Continued research will be needed to clarify the interactions between A.lancea and its endophytes.