Effects Of Inorganic Nutrients Research Articles

Effects of inorganic nutrients and environmental factors on the removal of n-propylbenzene and isopropylbenzene in seawater by cryptophytes Rhinomonas reticulata S6A

Effects of inorganic nutrients and environmental factors on the removal of n-propylbenzene and isopropylbenzene in seawater by cryptophytes Rhinomonas reticulata S6A

Effect of Inorganic Nutrients and Biofertilizers on Growth, Yield and Soil Properties of Maize (Zea mays L.) in N-W Region of Punjab, India

The field experiment on “Effect of inorganic nutrients and bio fertilizers on growth and yield of Maize (Zea mays. L) in N-W region of Punjab” was carried out at the research farm of Guru Kashi University, Talwandi Sabo, Bathinda (Punjab) during kharif season 2022. The experiment comprising total 8 treatment combinations; viz:, T0-control, T1- (100 percent RDF), T2 NP (150 kg per ha;70 kg per ha), T3-NP (100 kg per ha; 40 kg per ha) + Azospirillum, T4-NPK (140 kg per ha; 70 kg per ha; 70 kg per ha), T5- NPK (110 kg per ha; 40 kg per ha; 30kg per ha) +Azotobacter, T6- NPK+Zn (150kg per ha; 70 kg per ha; 70 kg per ha) + 50 kg per ha, T7- NPK +S+ S +Zn (160 kg per ha;70 kg per ha;70 kg per ha) + 50 kg per ha +30 kg per ha, T8-NPK (110kg per ha; 50kg per ha; 50kg per ha) + Azotobacter +Azospirillum. Experiment was carried out in randomized block design with three replications. Results revealed that growth, yield and economics of Maize influenced significantly due to application of nitrogen practices. The highest grain yield of 59.70 quintal per ha and stover yield 93.4 quintal per ha was recorded with combined application of NPK + S + Zn (160 kg per ha; 70 kg per ha; 70 kg per ha) + 50 kg per ha + 30 kg per ha (T7).

Controls on the Concentration of Bacterial Cell Surface Sulfhydryl Sites: Effects of Inorganic Nutrients

Understanding the controls on bacterial surface sulfhydryl site concentrations is crucial for modeling the effects of bacterial cells on the fate and transport of chalcophile metals in the environment. In this study, we investigate the effects of changing the concentrations of MgSO4, NaCl and NaNO3 in a growth medium on the concentration of cell surface sulfhydryl sites on the Gram-positive bacterial species Bacillus subtilis, as measured using a potentiometric titration approach. Our results show that the concentration of MgSO4 in a M9 minimal medium exerts a strong influence on bacterial surface sulfhydryl site concentrations under low MgSO4 concentrations but that this effect plateaus with increasing MgSO4 concentrations, indicating that a minimum amount of a sulfur source is required for bacteria to produce cell surface sulfhydryl sites. Although the sulfhydryl site concentration was below the detection limit on biomass samples that were grown in a M9 minimal medium containing 0.1 mM MgSO4, increasing the concentration of either NaCl or NaNO3 in the medium yielded biomass samples with measurable sulfhydryl site concentrations on the cell surface. In contrast, adding NaClO4 to the M9 medium did not increase cell surface sulfhydryl site concentrations. The NaCl and NaNO3 effects likely arise because increasing the concentration of NaCl or NaNO3 in a M9 minimal medium can promote the production of EPS by bacteria, and because the surface sulfhydryl sites of B. subtilis are located mostly on its EPS molecules. The results of this study suggest that bacterial nutrients and water chemistry composition are key controls on the abundance of bacterial surface sulfhydryl sites.

Effects of inorganic nutrients on the phytoplankton community in the sea surface microlayer of Daya Bay, South China Sea

The sea surface microlayer (SML), which is the uppermost layer of the water column between the ocean and atmosphere, has unique physicochemical and biological properties and plays a significant role in biogeochemical processes. Water samples were collected from the SML of Daya Bay in Southern China between June and August of 2013. Algal growth potential (AGP) tests were conducted following the addition of different concentrations of inorganic nitrogen (N), phosphorus (P) and silicate (Si) under laboratory conditions. The purpose of this study was to evaluate the effects of nutrient enrichment on phytoplankton in the SML. Chl a increased significantly after nutrient addition, and the biggest increase occurred in test groups with the addition of three nutrient elements. Nutrient concentrations decreased sharply, along with the growth of phytoplankton. Photoprotective carotenoids (PPCs) generally decreased after nutrient addition, while photosynthetic carotenoids (PSCs) became prominent after nutrient addition. Phytopigments were dominated by zeaxanthin (Zea), which contributed to 36.7%–79.4% of the total accessory pigments (TAcc). The next most abundant pigment was fucoxanthin (Fuco), with proportions of 15.2%–39.3%. Percentages of Zea decreased significantly after nutrient addition, and those of Fuco increased accordingly. The results suggest that the phytoplankton in the SML in Daya Bay is dominated by cyanobacteria followed by diatoms but that nutrient addition (i.e. eutrophication) might lead to a switch in dominance.

Effect of inorganic nutrients on bacterial community composition in oil-bearing sandstones from the subsurface strata of an onshore oil reservoir and its potential use in Microbial Enhanced Oil Recovery.

Microbial Enhanced Oil Recovery (MEOR) is a promising strategy to improve recovery of residual oil in reservoirs, which can be performed by promoting specific indigenous microorganisms. In this study, we performed preliminary evaluation of the possibility of conducting MEOR at Mae Soon reservoir, an onshore reservoir in Northern Thailand. The reservoir’s physicochemical characteristics, including the characteristics of the wells, the oil-bearing sandstone cores, and the reservoir’s produced water, were determined. The microbiological characteristics of the oil wells in the reservoir were also investigated by submerging the reservoir’s sandstone core samples, obtained from 6 oil wells, in the reservoir’s produced water and in the produced water added with inorganic nutrients (KNO3 and NaH2PO4). The uncultured bacteria in both treatments were determined, using tagged 16S rRNA gene amplicon with Ion Torrent Sequencing Analysis. The effects of inorganic nutrients and the reservoir’s parameters on the bacterial communities were analysed. A total number of 16,828 OTUs were taxonomically classified into 89 classes and 584 genera. In the controls (sandstone cores submerged in the produced water), the dominant bacterial populations were related to Deinococcus-Thermus, and Betaproteobacteria; while in the nutrient treated samples, there was a marked increase in the relative abundance of Gammaproteobacteria in three samples. Thermus, Acinetobacter, and Pseudomonas were the most abundant genera, and these are potential microorganisms for MEOR. Analysis of correlations between physiochemical properties of the reservoir and bacterial genera, using spearman’s correlation analysis, suggested that some of the reservoir’s properties, especially of the well and the rock, could influence some bacterial genera. To our knowledge, this is the first demonstration of the effect of inorganic nutrients on alteration of bacterial communities attached to reservoir’s rock, and how the bacterial, physical, and chemical properties of a reservoir were co-analysed to serve as a basis for designing a MEOR process.

Effect of inorganic nutrients and combine effect of inorganic and organic sources of nutrients on vegetative and reproductive growth of guava (Psidium guajava L.) cv. G-27

Effect of inorganic nutrients and combine effect of inorganic and organic sources of nutrients on vegetative and reproductive growth of guava (Psidium guajava L.) cv. G-27

Effects of inorganic nutrients in recycled water on freshwater phytoplankton biomass and composition

Planned indirect potable reuse water treated with advanced wastewater technologies (AWWT) to remove pollutants is increasingly being used to augment drinking water and groundwater supplies. While the treatment process substantially reduces the high nitrogen (N) and phosphorus (P) concentrations typically of wastewater, both nutrients can remain at concentrations and in biologically available forms that may stimulate phytoplankton growth in nutrient-deficient systems. This study examined the short-term effect of N plus P additions, at a range of concentrations, on phytoplankton growth and species composition in mesocosm experiments in a subtropical reservoir. Nitrate (NO3) plus orthophosphate (PO4) concentrations as low as 50 and 5 μg L−1, respectively, resulted in significant increases in phytoplankton biomass, with a 3.99 μg L−1 increase in chlorophyll a concentration with every 10 μg L−1 increase in N plus 1 μg L−1 in P. The system was likely to be co-limited because the addition of N or P alone did not result in increased chlorophyll a concentrations compared with the control. However, the toxic cyanobacterium, Cylindrospermopsis raciborskii, had higher growth rates with P addition alone. This study has shown that inputs of AWWT water have the potential to increase the phytoplankton biomass in this subtropical reservoir, at least in the short term. Therefore, the effect of AWWT water on water quality in reservoirs should be further investigated before widespread application occurs.

Effects of inorganic nutrients and organic matter on microbial euendolithic community composition and microbioerosion rates

Closed cages were used in Glovers Atoll, Belize to test the effects of organic matter (OM) and in- organic nutrient (N + P) additions on microbial euendo- lithic communities (bacteria, fungi, and algae) and their rates of bioerosion of Strombus gigas shells during a 49 d fertilization experiment. We hypothesized that the addi- tion of OM would release heterotrophic microborers from C-limitation and at the same time reduce light levels for euendolithic microalgae, thus changing the mi- croborers' community composition and their bioerosion rates. The addition of OM increased the abundance of heterotrophs (particularly fungi), but only when OM was added alone, not when it was combined with inorganic nutrients. In contrast, both cyanobacteria and green algae were stimulated by the addition of inorganic nutri- ents, but were not affected by OM; these taxa were 4 times more abundant in treatments with inorganic nutri- ents than in control and OM treatments. Green algae dominated the control, N + P and N + P + OM treatments (77 to 87% green algae, 6 to 8% cyanobacteria, 4 to 16% heterotrophs), whereas in the OM treatment, hetero- trophs represented nearly 50% of the total area colo- nized (52% green algae, 4% cyanobacteria, 44% het- erotrophs). Bioerosion rates in treatments with added inorganic nutrients (396 g CaCO3 m -2 yr -1 in the N + P treatment and 370 g CaCO3 m -2 yr -1 in the N + P + OM treatment) were 9-fold greater than bioerosion rates in the control and OM treatments (43 and 48 g CaCO3 m -2 yr -1 , respectively), and were not affected by OM addi- tion. We conclude that inorganic nutrients are a major factor controlling the microbioerosion rates and the abundance of euendolithis algae over fungi in carbonate substrata. Microborers act in synergy with the grazers that feed on them and with macroborers that increase the internal surfaces available for microborers to colo- nize. As a result, increased nutrients can initiate a feedback loop where bioerosion processes reinforce one another, leading to accelerated erosion of the reef framework.

Effects of inorganic nutrients, glucose and solar radiation on bacterial growth and exploitation of dissolved organic carbon and nitrogen in the northern Baltic Sea

Factors controlling bacterial growth and degradation of dissolved organic carbon (DOC) and nitrogen (DON) in the productive surface layer were investigated during the main summer stages of phytoplankton growth in the Gulf of Finland. The effects of different combinations of ammo- nium, phosphate, glucose, flagellates, and sunlight pre-exposure treatments were followed for 2 to 3 wk in natural bacterial (<0.7 µm pre-filtered) samples. Bacteria degraded the indigenous labile DOC and DON pools within 1 wk. The labile shares of total DOC and DON were <1 to 5 and 13 to 21%, respectively, and their depletion showed no important treatment effects. Nevertheless, photo- chemical transformations of DOC and DON (sunlight pre-treatment over 1 d) resulted in increased bacterial production. The phytoplankton system was N-limited in early summer, but showed a shift towards combined P and N deficiency during the late summer bloom of filamentous, N2-fixing cyanobacteria. Ambient labile DOC:DON ratios were low, increasing from <1-3 (mol mol -1 ) in early summer to 3-7 in late summer, and addition of glucose led to a significant bacterial production response. Thus, it appears that bacteria were consistently limited by the low availability of labile DOC, while phytoplankton exhausted the available free mineral nutrient pools, thereby creating a situation combining C-limited bacterial growth with mineral nutrient-limited phytoplankton growth.

Biodegradation of hexachlorocyclohexane (HCH) by microorganisms

The organochlorine pesticide Lindane is the gamma-isomer of hexachlorocyclohexane (HCH). Technical grade Lindane contains a mixture of HCH isomers which include not only gamma-HCH, but also large amounts of predominantly alpha-, beta- and delta-HCH. The physical properties and persistence of each isomer differ because of the different chlorine atom orientations on each molecule (axial or equatorial). However, all four isomers are considered toxic and recalcitrant worldwide pollutants. Biodegradation of HCH has been studied in soil, slurry and culture media but very little information exists on in situ bioremediation of the different isomers including Lindane itself, at full scale. Several soil microorganisms capable of degrading, and utilizing HCH as a carbon source, have been reported. In selected bacterial strains, the genes encoding the enzymes involved in the initial degradation of Lindane have been cloned, sequenced, expressed and the gene products characterized. HCH is biodegradable under both oxic and anoxic conditions, although mineralization is generally observed only in oxic systems. As is found for most organic compounds, HCH degradation in soil occurs at moderate temperatures and at near neutral pH. HCH biodegradation in soil has been reported at both low and high (saturated) moisture contents. Soil texture and organic matter appear to influence degradation presumably by sorption mechanisms and impact on moisture retention, bacterial growth and pH. Most studies report on the biodegradation of relatively low (< 500 mg/kg) concentrations of HCH in soil. Information on the effects of inorganic nutrients, organic carbon sources or other soil amendments is scattered and inconclusive. More in-depth assessments of amendment effects and evaluation of bioremediation protocols, on a large scale, using soil with high HCH concentrations, are needed.

Effects of inorganic nutrients on the regrowth of heterotrophic bacteria in drinking water distribution systems

Three laboratory-scale water pipe systems were set up to study the effects of adding three inorganic nutrients (ammonium, nitrate or phosphate) on biofilm formation in water pipes. The results showed that the effects of adding ammonium or nitrate on the biofilm formation were insignificant when levels below 0.1 mg N/l were added. Analogous results were observed when phosphate was added at levels below 0.005 mg P/l. However, as the addition of ammonium increased to 0.5 mg N/l, significant effects on biofilm formation were observed. Similar results were obtained phosphate was added at levels above 0.01 mg P/l. Batch tests were also conducted using water samples collected from a Taiwanese drinking water distribution system. The results indicated that the addition of ammonium, nitrate or phosphate to treatment plant effluent stimulates bacterial growth. In the distributed water of an urban area, the addition of nitrate or phosphate stimulated bacterial growth. The bacterial growth in the distributed water of a suburban area was not stimulated by adding any of these three inorganic nutrients.

Effect of inorganic nutrients on relative contributions of fungi and bacteria to carbon flow from submerged decomposing leaf litter.

The relative contributions of fungi and bacteria to carbon flow from submerged decaying plant litter at different levels of inorganic nutrients (N and P) were studied. We estimated leaf mass loss, fungal and bacterial biomass and production, and microbial respiration and constructed partial carbon budgets for red maple leaf disks precolonized in a stream and then incubated in laboratory microcosms at two levels of nutrients. Patterns of carbon flow for leaf disks colonized with the full microbial assemblage were compared with those colonized by bacteria but in which fungi were greatly reduced by placing leaf disks in colonization chambers sealed with membrane filters to exclude aquatic hyphomycete conidia but not bacterial cells. On leaves colonized by the full microbial assemblage, elevated nutrient concentrations stimulated fungi and bacteria to a similar degree. Peak fungal and bacterial biomass increased by factors of 3.9 and 4.0; cumulative production was 3.9 and 5.1 times higher in the high nutrient in comparison with the low nutrient treatment, respectively. Fungi dominated the total microbial biomass (98.4 to 99.8%) and cumulative production (97.3 and 96.5%), and the fungal yield coefficient exceeded that of bacteria by a factor of 36 and 27 in low- and high-nutrient treatments, respectively. Consequently, the dominant role of fungi in leaf decomposition did not change as a result of nutrient manipulation. Carbon budgets indicated that 8% of leaf carbon loss in the low-nutrient treatment and 17% in the high-nutrient treatment were channeled to microbial (essentially fungal) production. Nutrient enrichment had a positive effect on rate of leaf decomposition only in microcosms with full microbial assemblages. In treatments where fungal colonization was reduced, cumulative bacterial production did not change significantly at either nutrient level and leaf decomposition rate was negatively affected (high nutrients), suggesting that bacterial participation in carbon flow from decaying leaf litter is low regardless of the presence of fungi and nutrient availability. Moreover, 1.5 and 2.3 times higher yield coefficients of bacteria in the reduced fungal treatments at low and high nutrients, respectively (percentage of leaf carbon loss channeled to bacterial production), suggest that bacteria are subjected to strong competition with fungi for resources available in leaf litter.

Effects of nutrients (phosphorous, nitrogen, and carbon) and zooplankton on bacterioplankton and phytoplankton—a seasonal study

The effects of inorganic nutrients (P and N), organic C, and metazoan zooplankton on bacterioplankton production and abundance and on phytoplankton biomass were studied in five experiments (from May to September) in Lake Erken. In addition, the seasonal dynamics of bacterioplankton and phytoplankton were followed in the lake from April to November.Bacterioplankton production was P limited from May to August. N alone never stimulated bacterioplankton production, but bacterioplankton growth was close to colimited by P and N in July and August. Organic C stimulated bacterial production in June and September. Zooplankton enhanced bacterioplankton production in June, when bacterioplankton production was limited by P and C and the phytoplankton biomass in the lake was low. N alone stimulated phytoplankton growth in all experiments. In addition, P alone stimulated phytoplankton growth in May and July, and the combination of P and N stimulated phytoplankton growth in July and August. Zooplankton additions resulted in a decrease in phytoplankton biomass in May and September, mainly owing to grazing on Cryptophyceae.The experimental results indicate that bacterioplankton and phytoplankton growth were uncoupled during most of the open‐water period because P primarily limited bacterioplankton growth and N limited phytoplankton growth. The response of the bacterioplankton community was most likely a direct effect of nutrient additions. Primary production and bacterioplankton production were correlated during the season, but partial correlations analysis indicates that this relationship can be attributed to the fact that both primary production and bacterioplankton production showed strong positive correlations with temperature. We suggest that uncoupling of bacterioplankton production and phytoplankton production may be a common phenomenon in lakes.

Effects of inorganic nutrients and zooplankton on the growth of heterotrophic bacterioplankton - enclosure experiments in an oligotrophic clearwater lake

Bacterioplankton production and abundance were studied in the oligotrophic clearwater Lake Njupfatet (Sweden) during 2 consecutive years (1989 and 1990). The lake was slightly acidic in 1989 and wa ...

The Trophic Diatom Index: a new index for monitoring eutrophication in rivers

A index for monitoring the trophic status of rivers based on diatom composition ('trophic diatom index', TDI) has been developed, in response to the National Rivers Authority (England & Wales)'s needs under the terms of the Urban Wastewater Treatment Directive of the European Community. The index is based on a suite of 86 taxa selected both for their indicator value and ease of identification. When tested on a dataset from 70 sites free of significant organic pollution, this index was more highly correlated with aqueous P concentrations than previous diatom indices. However, where there was heavy organic pollution, it was difficult to separate the effects of eutrophication from other effects. For this reason, the value of TDI is supplemented by an indication of the proportion of the sample that is composed of taxa tolerant to organic pollution. The index was tested on the R. Browney, N-E. England, above and below a major sewage discharge. TDI values indicated that the effect of inorganic nutrients on the river downstream of the discharge was slight as the river was already nutrient-rich, but there was a large increase in the proportion of organic pollution-tolerant taxa. This indicates that the river was already so eutrophic upstream of the discharge that tertiary treatment to remove P would not be effective unless other aspects of the discharge were also improved.

Interactions between subsurface microbial assemblages and mixed organic and inorganic contaminant systems

Metals are introduced into aquatic environments as results of mining and refining of ores and other human activities, such as combustion of fossil fuels, spraying of pesticides, and disposal of domestic and industrial wastes. Synthetic chelating agents have been used for nuclear decontamination, waste processing, and detergent industry because they react with radionuclides and heavy metal ions and form stable water-soluble complexes. Co-disposal of synthetic chelating agents with radionuclides and/or heavy metals at some landfill sites for energy and industrial wastes have caused increase in organic-inorganic mixtures transport in the subsurface environment. The extensive presence and the possible persistence of these waste mixtures in those environments underlines the need to study their effects on aquatic microbial assemblages. To remediate a contaminated aquifer, the microorganisms must not be severely inhibited by the chemical pollutants. In this research, the effects of selected chemical contaminants (organic and inorganic species) on ground water bacteria and a mixture of model organic and inorganic chemicals (i.e., imidazole and copper) on surface and subsurface bacteria were determined. Adaptation of microorganisms to in situ contaminants may be the prerequisite for microbial degradation to occur. In addition, some environmental factors such as concentrations of inorganic nutrients may limit ormore » affect biodegradation of subsurface organic pollutants. Microbial degradative activity in ground water of a chemical waste landfill site in Georgia and in ground water samples from California were the focus of this study. Effects of inorganic nutrients on microbial degradation of toluene, p-cresol, and phenol in ground waters were evaluated. 14 refs., 3 figs., 1 tab.« less

Effect of inorganic nutrients on the acclimation period preceding mineralization of organic chemicals in lake water.

The addition of phosphate, nitrate, or sulfate (each at 10 mM) decreased the acclimation period for the mineralization of low concentrations of p-nitrophenol (PNP) in lake water. Added phosphate shortened the acclimation period for biodegradation of 2 ng to 2 micrograms of PNP per ml in various lake water samples and of 2,4-dichlorophenoxyacetate at 100 ng/ml. Added P enhanced the rate of growth of PNP-mineralizing microorganisms in waters containing 200 ng or 2 micrograms of PNP per ml. We suggest that the effect of P on the acclimation period results from an increase in the growth rate of the initially small population of microorganisms able to mineralize the synthetic chemicals.

Effects of Inorganic Nutrients on Microbial Leaf Decomposition and Mitigation of Chemical Perturbation

ABSTRACT A laboratory study was conducted to determine (1) the effects of inorganic nitrogen and phosphorus enrichment on microbial leaf processing, and (2) whether inorganic nutrient enrichment would mitigate the effects of chemical perturbation of microbial leaf processing. Pre-leached disks from leaves of Acer saccharum were incubated in flasks of unfiltered stream water at 20°C for 56 days. Treatments consisted of a control, killed control (100.0 mg/1 HgCl2), nitrogen (3.0 mg/1 NO3-N), phosphorus (0.1 mg/1 PO4-P), nitrogen + phosphorus (3.0 mg/1 NO3-N + 0.1 mg/1 PO4-P), pentachlorophenol (10.0 mg/1 Na-salt of pentachlorophenol), and pentachlorophenol + nitrogen + phosphorus (10.0 mg/1 Na-salt of pentachlorophenol t 3.0 mg/1 NO3-N + 0.1 mg/1 PO4-P). Leaf disks in the control treatment lost 31% of ash-free dry weight in 56 days. Leaf decomposition, microbial biomass, and microbial activity increased in all treatments enriched with nitrogen. However, there were no increases in the treatment receiving onl...

Effects of Mineral Nutrition on Endogenous Cytokinins in Plants of Sunflower (Helianthus annuusL.)

The effects of inorganic nutrients on the levels of endogenous cytokinins in plants of sunflower (Helianthus annuus L.) grown in sand culture were studied. Low levels of nitrogen resulted in rapid decreases in the levels of cytokinins extracted from leaves, buds, roots, and root exudates. Similar effects were observed with phosphorus deficiency, but the effects of potassium deficiency on the cytokinin content of leaves was less marked. The cytokinin content was higher in plants supplied with nitrogen as nitrate than in those supplied with ammonium sulphate or ammonium nitrate. The decline in cytokinin levels in derooted shoots and detached leaves could be reversed by supplying them with nutrient solution. Although leaves on intact plants may normally be dependent upon the supply of cytokinins from the roots, isolated leaves have the capacity for cytokinin production when supplied with inorganic nutrients.

Effect of Inorganic Nutrients on Production of Steroid Glycoalkaloids by Phytophthora infestans Race 1.2.4 In Vitro

The influence of sodium salts of the macronutrients nitrate, phosphate, sulfate, and chloride; and the micronutrients iron, calcium, copper, cobalt, nickel, and manganese on growth of Phytophthora infestans and synthesis of glycoalkaloids by the fungus was investigated. Maximum growth levels were demonstrated when 0.04% phosphate, 0.04% chloride, or 2–5 mg of iron/liter were employed in the culture medium. Results indicate that upon substitution of the individual sodium salts of the macronutrients for the potassium and magnesium salts or addition of sodium chloride to the basal medium, the concentration of glycoalkaloids synthesized by the fungus decreased significantly. Regression analysis showed that the concentration of phosphate in the medium had the most influence on the amount of glycoalkaloids produced by P. infestans. Increasing the phosphate concentration in the medium resulted in increasing amounts of glycoalkaloids being produced by the fungus. As the mass of mycelium increased in media containing different amounts of phosphate, the quantity of glycoalkaloids synthesized by the fungus decreased.