Effects Of Phosphorus Supply Research Articles

Effects of phosphorus supply and salt stress on plant growth, organic acid concentration, and sodium, potassium, calcium, magnesium, and phosphorus utilization in wheat

Effects of phosphorus supply and salt stress on plant growth, organic acid concentration, and sodium, potassium, calcium, magnesium, and phosphorus utilization in wheat

Effects of Phosphorus Supply on Seed Yield and Quality in Flax

Flaxseed, which is rich in lignan, α-linolenic acid, dietary fiber, and several minerals, is an important food and nutrition source. In this study, trials were conducted at Yongdeng over two consecutive years (2018 and 2019), with three cultivars (Longyaza 1, Longya 14, and Zhangya 2) and five application rates of phosphorus (P) (0, 40, 80, 120, and 160 kg P2O5 ha−1). We examined the effects of P on the seed yield, and the yields and contents of dietary fiber, lignan, iron (Fe), zinc (Zn), manganese (Mn), and copper (Cu). We found that P fertilization positively influenced yields of seed and levels of lignan, Fe, and Cu, showing average increases of 15, 20, 24, and 28%, respectively, compared with plants not given P over the 2-year study. Additionally, P fertilization resulted in increased concentrations of Fe and Cu in flaxseed of 8 and 2%, respectively. P fertilization negatively affected the levels of dietary fiber, Zn, and Mn, which were reduced by 7, 11, and 7%, respectively, in comparison with the control. In conclusion, the results demonstrated that appropriate P application is an effective strategy for improving yields of seed, lignan, Fe, and Cu in flax production and for enhancing concentrations of Fe and Cu in flax.

Effects of Phosphorus Supply on the Leaf Photosynthesis, and Biomass and Phosphorus Accumulation and Partitioning of Canola (Brassica napus L.) in Saline Environment

Salt stress is a major negative factor affecting the sustainable development of agriculture. Phosphorus (P) deficiency often occurs in saline soil, and their interaction inhibits plant growth and seed yield for canola (Brassica napus L.). P supply is considered an effective way to alleviate the damage of salt stress. However, the knowledge of how P supply can promote plant growth in saline environment was limited. A field experiment was conducted to explore the effects of P rate on accumulation, and partitioning, of biomass and P, leaf photosynthesis traits, and yield performance in saline soil in the coastal area of Yancheng City, Jiangsu Province, China, during the 2018–2019 and 2019–2020 growing seasons. P supply increased biomass and P accumulation in all organs, and root had the most increments among different organs. At flowering stage, P supply increased the biomass and P partitioning in root and leaf, but it decreased the partitioning in stem. At maturity stage, P supply facilitated the biomass and P partitioning in seed, but it decreased the partitioning in stem and shell, and it increased the reproductive-vegetative ratio, suggesting that P supply can improve the nutrients transporting from vegetative organs to reproductive organs. Besides, P supply improved the leaf area index and photosynthetic rate at the flowering stage. As a result, the seed yield and oil yield were increased. In conclusion, P supply can improve the canola plant growth and seed yield in a saline environment. P fertilizer at the rate of 120 kg P2O5 ha−1 was recommended in this saline soil.

Effects of Phosphorus Supply on Root Morphology and Phosphorus Uptake in Maize Seedlings under Different Water Regimes

Water deficit and phosphorus (P) deficiency in soil have become the main limiting factors for the production of maize (<i>Zea mays</i> L.), but it still remains unclear how water and P regulate maize root morphology and P uptake. Through an experiment of potted soil culture, this study has set 4 water gradients [35% (W1), 55% (W2), 75% (W3) and 100% (W4)] of field capacity, and two P levels [high P: 205 mg (P)∙kg^-1; low P: 11 mg (P)∙kg^-1] to investigate the coupling effects of water and P on root growth and P uptake in maize seedlings. The results have shown that: (1) Regardless of soil P supply, the shoot dry weight, root dry weight, total root length, and root surface area of maize seedlings shows a trend of increasing first and then decreasing with increasing water supply intensity; the soil available P content also shows similar trend; the root mass ratio and mean root diameter shows a downward trend with the increase of water supply intensity; furthermore, the P content and P accumulation of plants shows a steady increase with the increase of water supply intensity; (2) Water deficit (W1) and excess water supply (W4) is not conducive to root growth and dry matter accumulation in maize. Water deficit (W1) inhibits the acquisition of soil P by maize, while excess water supply (W4) causes extravagant absorption of soil P (W4). Mild water stress (W2) can promote the growth and dry matter accumulation of maize roots and reduce the extravagant absorption of soil P, and adequate water supply (W3) can promote root growth, dry matter accumulation and the absorption of soil P; (3) Phosphorus supply significantly increases the dry weight, root dry weight (except W4), total root length, root surface area, plant P content (except W4) and P accumulation of maize seedlings, but reduces the root mass ratio of maize. It is thus evident that water is a key factor controlling the morphology and accumulation of dry matter in maize roots, and P is a key factor controlling P uptake and soil available P content in corn field. The better coupling between water and P can promote maize root growth and dry matter accumulation, as well as reduce the extravagant absorption of soil P.

Zinc toxicity to Daphnia magna in a two-species microcosm can be predicted from single-species test data: The effects of phosphorus supply and pH.

Ecological interactions and abiotic stress factors may significantly affect species sensitivities to toxicants, and these are not incorporated in standard single-species tests. The present study tests whether a model, calibrated solely on single-species data, can explain abiotic stress factors in a two-species microcosm, a test applied to the effects of nutritional stress (phosphorus [P] limitation) on zinc (Zn) toxicity to Daphnia magna. A population model was developed based on P- and Zn-dependent algal and daphnid growth. Two separate two-species (phytoplankton Pseudokirchneriella subcapitata and consumer D. magna) microcosm experiments with P × Zn factorial combinations and a different pH (7.3 and 7.8) were set up to validate the model. The 21-d daphnid population size was considerably reduced by increased Zn and by decreased P supply, with a significant (p < 0.001) interaction between the 2 factors. The observed median effective concentration (EC50) of Zn on D. magna population size varied 12-fold (25 to 310 μg Zn L-1 ), with the lowest EC50 values found at the highest pH and high P treatments. For both experiments, Zn toxicity to D. magna was correctly predicted within a factor of 2 for EC50 values, and this is explained by the model through 1) a higher phytoplankton Zn sensitivity at higher pH, affecting food supply to D. magna, and 2) an increased algal P content at higher Zn, offering a nutritional benefit to daphnids that counteracts direct Zn toxicity under P limitation. The present study illustrates that indirect effects of Zn via producer-consumer relationships can outweigh the direct toxic effects and that models calibrated solely on single-species test data can help with interpreting these results in two-species systems. Environ Toxicol Chem 2018;37:2153-2164. © 2018 SETAC.

Effects of phosphorus supply on the quality of green tea

Self-rooted, 10-month-old, uniform tea [Camellia sinensis (L.) O. Kuntze cv. Huangguanyin] plants were supplied with 0, 40, 80, 160, 400 or 1000μM phosphorus (P) for 17weeks to determine how P-deficiency affects the quality of green tea. Leaf P concentration increased with increasing P supply. Whole plant dry weight (DW) increased as P supply increased from 0 to 160μM, then remained little changed with further increasing P supply. The P-deficient green tea displayed decreased concentrations of water extract, total polyphenols, flavonoids, total free amino acids, theanine (Thea) and asparagic acid (Asp)+glutamic acid (Glu), increased concentrations of water soluble sugars, valine (Val), γ-aminobutyric acid (GABA), proline (Pro) and cysteine (Cys), and ratio of total polyphenols to total free amino acids, but unchanged concentrations of total catechins and epigallocatechin gallate (EGCG). In conclusion, the sensory and biochemical qualities of green tea were lowered by P-deficiency.

Effects of phosphorus supply on growth, phosphate concentration and cluster-root formation in three Lupinus species.

In some lupin species, phosphate deficiency induces cluster-root formation, which enhances P uptake by increasing root surface area and, more importantly, the release of root exudates which enhances P availability. Three species of Lupinus, L. albus, L. atlanticus and L. micranthus, with inherently different relative growth rates were cultivated under hydroponics in a greenhouse at four phosphate concentrations (1, 10, 50 and 150 microm) to compare the role of internal P in regulating cluster-root formation. The highest growth rate was observed in L. atlanticus, followed by L. albus and L. micranthus. At 1 microm P, cluster-root formation was markedly induced in all three species. The highest P uptake and accumulation was observed in L. micranthus, followed by L. atlanticus and then L. albus. Inhibition of cluster-root formation was severe at 10 microm P in L. atlanticus, but occurred stepwise with increasing P concentration in the root medium in L. albus. In L. atlanticus and L. albus cluster-root formation was suppressed by P treatments above 10 microm, indicating a P-inducible regulating system for cluster-root formation, as expected. By contrast, production of cluster roots in L. micranthus, in spite of a high internal P concentration, indicated a lower sensitivity to P status, which allowed P-toxicity symptoms to develop.

Fósforo como possível mitigador dos efeitos da deficiência hídrica sobre o crescimento e as trocas gasosas de Brachiaria brizantha cv. MG-5 Vitória

Water deficit is the most constraining factor on crop yield, reducing both plant photosynthesis and growth. Because of the economical importance of tropical grasses, which also are affected by water shortage, the objective of this study was to test the effects of phosphorus supply (24, 50, 100 and 150 mg P dm -3 ) in Brachiaria brizantha cv. MG-5 Vitoria plants cultivated under water deficit. Plants were evaluated taking into account leaf gas exchanges and crop yield parameters. The study was carried out under greenhouse conditions, and the water deficit was imposed by irrigation withholding until the first sign of leaf wilting in 50-days-old plants. A control treatment was maintained, with plants under daily irrigation and the same P concentrations. Phosphorus supplying caused positive effects on plant growth parameters, mainly in leaf area and new shoot formation. Water deficit reduced stomatal conduction and net CO 2 assimilation in all treatments. However, a significant improvement was observed in gas exchange recovering after re-hydration in the plants with additional P supplying, which could support faster growth improvements after a dry season.

The impact of phosphorus on interactions of the hemiparasitic angiosperm Rhinanthus minor and its host Lolium perenne

The effects of phosphorus supply on the outcome of interactions between the hemiparasitic angiosperm Rhinanthus minor L. with its host species Lolium perenne L. were investigated in a glasshouse experiment. Host plants were grown in 3-l pots in the presence and absence of R. minor at limiting (0.13 mM P) and optimal (0.65 mM P) concentrations of phosphorus for the growth of the host species. Phosphorus was supplied at 2-day intervals in the form of half-strength Long Ashton nitrate-based solution with phosphorus concentrations adjusted accordingly. Parasitism by R. minor significantly suppressed host growth, with final biomass losses ranging between 32% and 44%. Phosphorus supply had a marked impact on the outcome of the host-parasite interaction. By the end of the growing period, parasite biomass at 0.65 mM P was 90% lower than that achieved at 0.13 mM P. In contrast, host biomass at 0.65 mM P was 74% higher than achieved at 0.13 mM P, indicting that the negative impact of parasitism on the host species was reduced when phosphorus supply was increased. The effects of phosphorus on the host-parasite association appeared to be mediated by changes in both the morphological characteristics of the host roots and the relative sink strengths of the host and parasite.

Effects of phosphorus supply on phagotrophy by the mixotrophic alga Uroglena americana (Chrysophyceae)

Effects of phosphorus supply on phagotrophy by the mixotrophic alga Uroglena americana (Chrysophyceae)

Phosphorus nutrition of spring wheat (Triticum aestivum L.). 1. Effects of phosphorus supply on plant symptoms, yield, components of yield, and plant phosphorus uptake

The effects of phosphorus (P) deficiency on plant symptoms, yield, and components of yield of wheat (Triticum aestivum L. cv. Halberd), P uptake, and the distribution of dry weight within plants of variable P status were examined in 2 glasshouse and 5 field experiments. Apart from stunted growth and depressed tillering, the symptoms of acute P deficiency, most noticeable on older leaf blades, were equivocal; they were not always observed on acutely deficient plants and were absent on moderately deficient plants. In glasshouse experiments, the leaves of acutely deficient plants were spindly, erect, and dark green, whereas in field experiments, the leaves were pale green. In acutely P-stressed plants, leaf senescence, phasic development, and anthesis were delayed. The disorder restricted tiller development and therefore the rate of appearance and the number of leaves per plant. It depressed grain yield principally by reducing the number of fertile tillers. Severe P deficiency depressed shoot growth within 15 days of sowing and ultimately reduced plant height, root mass, and grain yield. In all experiments, shoot yield responses to applied P increased progressively until stem elongation (Zadoks Scale 30) and changed little thereafter. As a result, the external requirement for P (i.e. P level required for 90% maximum growth) increased with time during vegetative development in most experiments. Severe P deficiency also affected the distribution of dry matter between the roots and shoots and between the leaf blades and conducting tissues (sheaths and stems). Both of these responses intensified with advancing plant age. Treatment differences in P uptake in shoots also occurred early in growth and persisted until grain maturity. The partitioning of P between roots and shoots favoured P uptake or retention in the roots of P-deficient plants. Under conditions of acute and moderate P stress, the resources of the wheat plant appear to be directed towards maintaining root growth (at least initially), limiting and delaying shoot proliferation, and maximising the leaf : stem ratio. These regulations appear circumstantially to be adaptive mechanisms for conserving suffiient P to ensure the survival of at least 1 weak, but fertile, tiller on each plant.

Effects of phosphorus supply on in vitro growth and phosphatase activity of Frankia isolates from Casuarina

An in vitro experiment was conducted to investigate the effects of different sources and levels of P supply on growth, viability and phosphatase activity of three tropical Frankia strains isolated from Casuarina. P concentration for optimum growth was between 0.1 and 10.0 μM in the absence of external combined nitrogen. Specific viability was not influenced by P supply. Morphological features of Frankia, such as hyphal length and vesicle numbers, were found to largely mirror growth. Phosphatase activity was detected in all three Frankia strains and was highest when P was omitted from the culture solution. There were more than 10-fold differences between the Frankia strains in the level of phosphatase activities shown. This study suggested that soils low in P are unlikely to restrict micro-symbiont growth activity.

Effects of phosphorus supply on growth and nitrogen fractions in xylem sap and foliage of Eucalyptus regnans (F.Muell.), E. nitens (Maiden) and E. globulus (Labill.) seedlings: implications for herbivory

Rates of growth of seedlings of E. globulus, E. regnans and E. nitens were related to phosphorus supply in two soils but concentrations of total nitrogen and total phosphorus in most plant tissues did not vary significantly among soil or phosphorus treatments. Differences in concentrations of nitrogen and phosphorus and in the composition of the pool of free amino-acids among leaves at different stages of development were far greater than differences between treatments. The most significant of these differences were several-fold greater concentrations of arginine in the oldest leaves and these are most likely due to protein degradation and/or in situ synthesis since arginine is not generally phloem mobile. The concentration of reduced nitrogen in xylem sap was inversely related to growth and glutamine was by far the dominant nitrogenous solute. We suggest that specific nitrogenous solutes may be useful indices of the nitrogen status of eucalypt tissues for insect herbivores.

Phosphorus supply affects the photosynthetic capacity of loblolly pine grown in elevated carbon dioxide.

Effects of phosphorus supply and mycorrhizal status on the response of photosynthetic capacity to elevated CO(2) were investigated in loblolly pine (Pinus taeda L.) seedlings. Seedlings were grown in greenhouses maintained at either 35.5 or 71.0 Pa CO(2) in a full factorial experiment with or without mycorrhizal inoculum (Pisolithus tinctorius (Pers.) Coker & Couch) and with an adequate or a limiting supply of phosphorus. Assimilation versus internal CO(2) partial pressure (C(i)) curves were used to estimate maximum Rubisco activity (V(c,max)), electron transport mediated ribulose 1,5-bisphosphate regeneration capacity (J(max)), phosphate regeneration capacity (PiRC) and daytime respiration rates (R(d)). Nonmycorrhizal seedlings grown with limiting phosphorus had significantly reduced V(c,max) and PiRC compared to seedlings in other treatments. Elevated CO(2) increased photosynthetic capacity in nonmycorrhizal seedlings in the low phosphorus treatment by increasing PiRC, whereas it induced phosphorus limitation in mycorrhizal seedlings in the low phosphorus treatment and did not affect the photosynthetic capacity of seedlings in the high phosphorus treatment. Despite the variety of effects on photosynthetic capacity, seedlings in the elevated CO(2) treatments had higher net assimilation rates than seedlings in the ambient CO(2) treatments. We conclude that phosphorus supply affects photosynthetic capacity during long-term exposure to elevated CO(2) through effects on Rubisco activity and ribulose 1,5-bisphosphate regeneration rates.

Dinitrogen fixation and soil n uptake by soybean as affected by phosphorus availability

Abstract The effects of phosphorus supply (0, 30, and 90 mg P kg‐1) on growth, N2 fixation, and soil N uptake by soybean (Glycine max (L.) Merr.) were studied in a pot experiment using the 15N isotope technique. Phosphorus supply increased the top dry matter production at flowering and the dry matter production of seeds, straw, pod shells, and roots at late pod filling of inoculated soybeans. Phosphorus supply reduced the N concentration of plant tops at flowering, but increased the amount of N accumulated at both flowering and late pod filling. In inoculated soybeans total N accumulation paralleled the dry matter production. The P concentration in above‐ground plant parts of nodulated soybeans was not affected by P application. At flowering only 18 to 34% of total N was derived from N2 fixation, whereas as much as 74% was derived from N2 fixation at late pod filling. Only the addition of 90 mg P kg‐1 soil significantly increased the amount of N2 fixed at the late pod filling stage. Phosphorus supply did not influence the uptake of fertilizer or soil N in soybeans, even if the root mass was increased up to 60% by the P supply.

Zinc in subterranean clover (Trifolium subterraneum L. cv. Seaton Park). II. Effects of phosphorus supply on the relationship between zinc concentrations in plant parts and yield

The effect of phosphorus on the relationship of zinc concentrations in various plant parts to yield of Seaton Park subterranean clover was examined. Plants were grown in a glasshouse at three levels of phosphorus (39, 65 and 130 mg phosphorus/pot; denoted P1, P2 and P3 respectively) and six levels of zinc added in factorial combination to a sand deficient in both phosphorus and zinc. At the lowest three levels of zinc supply, plants were severely to moderately deficient in zinc: in them, increasing levels of phosphorus depressed growth and induced high concentrations of phosphorus (&gt; 1 % DM) in several plant parts and symptoms of phosphorus toxicity in leaves. At the highest three levels of zinc supply, plants at P1 were phosphorus deficient: application of P2 and P3 increased growth and induced zinc deficiency primarily by diluting the available zinc. In addition, P3 appeared to depress slightly the zinc content of plant tops by another mechanism. In severely zinc-deficient plants, phosphorus supply changed the relationships between zinc concentrations in various plant parts and yield of whole tops, probably as the result of phosphorus toxicity. In the youngest open leaf blades, an asymptotic relationship at P1 changed at P2 and P3 to sigmoidal and to 'Piper-Steenbjerg' relationships respectively. These changes would not have invalidated the use of plant analysis for diagnosing zinc deficiency. In moderately zinc-deficient plants, phosphorus supply had little or no effect on the relationships of zinc concentration in plant parts to yield of shoots. As a result, critical concentrations in plant parts generally remained constant over the whole range of phosphorus supply. The data refute suggestions that high levels of phosphorus in plant parts inactivate the zinc within them, thus removing a potential problem in the use of plant analysis for diagnosing zinc deficiency in subterranean clover. The results confirm the previous suggestion that a concentration range of 12-14 �g zinc/g in the youngest, open leaf blade is critical for diagnosis of zinc deficiency in subterranean clover.

Copper nutrition of subterranean clover (Trifolium subterraneum L. cv. Seaton Park). III. Effects of phosphorus supply on the relationship between copper concentrations in plant parts and yield

The effects of phosphorus supply on the relationship of copper supply with copper concentrations in various plant parts and yield of Seaton Park subterranean clover were examined. Plants were grown in a glasshouse for 40 and 74 days in pots with four levels of potassium phosphate (0, 13, 39, 65 mg phosphorus/pot) and six levels of copper sulfate (0, 50, 100, 200, 400, 800 pg copper/pot) added, in factorial combination, to a sand deficient in both phosphorus and copper. By increasing the phosphorus levels copper deficiency was induced partly by promoting growth and diluting copper concentrations in plants; and also by depressing copper absorption. Increasing phosphorus changed the distribution of copper in plant tops and the shape of curves relating copper concentration in whole plant tops to yield. At 39 mg phosphorus/pot, the relationship at Day 74 had a marked 'Piper-Steenbjerg' curvature, largely as a result of unusually high copper concentrations in the stems plus petioles of severely copper-deficient plants. At 65 mg phosphorus/pot, the relationship had no 'Piper-Steenbjerg' curvature for whole tops and only a relatively small curvature for stems plus petioles. The data suggests that 'Piper-Steenbjerg' curves in subterranean clover result primarily from high concentrations of copper in the stems plus petioles of severely deficient plants. At both harvests, young leaf blades had critical copper concentrations of around 3 �g copper/g at both 39 and 65 mg phosphorus/pot. However, copper-deficient plants with severe phosphorus deficiency did not respond to copper, and generally had copper concentrations below this critical level in all plant parts. The results confirm the value of copper analysis of young leaf blades for diagnosing copper deficiency in subterranean clover with moderately deficient to luxury supplies of phosphorus.

Involvement of Phosphorus in Nitrogen Fixation by Subterranean Clover (Trifolium subterraneum L.)

Effects of phosphorus supply on nodulation and nitrogen fixation in subterranean clover paralleled those on growth and occurred only after, or at the same time as, growth responses. However, correcting phosphorus deficiency increased nitrogen concentrations in tops as well as weight of tops. Effects of vesicular-arbuscular (VA) mycorrhizas on growth, nodulation and nitrogen fixation operated through effects on phosphorus nutrition of the host. Inoculation with a VA mycorrhizal fungus only stimulated nodulation and nitrogen fixation when insufficient phosphorus was applied for maximum growth of the non-mycorrhizal plant. Phosphorus concentrations in nodules greatly exceeded those in either tops or roots in both mycorrhizal and non-mycorrhizal plants and with phosphorus levels ranging from severely deficient to luxury supply for plant growth. Nitrogen applied after nitrogen fixation had commenced increased fresh weight of tops to a greater extent where phosphorus was non-limiting to growth. This positive interaction between nitrogen and phosphorus on the growth of nodulated nitrogen-fixing subterranean clover suggests that phosphorus deficiency does not limit growth in legumes by decreasing nitrogen fixation. It is concluded that increasing phosphorus supply increases nitrogen fixation in subterranean clover by stimulating host plant growth rather than by effects on either rhizobial growth and survival or on nodule formation and function.

The Effects of Phosphorus Supply on The Rates of Intake of Phosphorus and Nitrogen and Upon Certain Aspects of Phosphorus Metabolism in Gramineous Plants

For experiments previously described, new data are presented relating to the intake of phosphorus by gramineous plants, its distribution within the plant, and its partition in the leaves between alcohol-soluble, nucleic-acid, and "residual" phosphorus.