Mineral Nutrient Conditions Research Articles

Correlating Coffea canephora 3D architecture to plant photosynthesis at a daily scale and vegetative biomass allocation.

Coffea canephora (C. canephora) has two botanical varieties, Robusta and Conilon. Intraspecific variability was hypothesized and projected for the selection of C. canephora plants able to maintain production in the context of global climate changes. For that, architectural, C-assimilation and biomass analyses were performed on 17-month-old Robusta (clones 'A1' and '3V') and Conilon (clones '14' and '19') varieties grown in non-limiting soil, water and mineral nutrient conditions. Nondestructive coffee plant architecture coding, reconstruction and plant photosynthesis estimations were performed using a functional-structural plant modeling platform OpenAlea. 3D reconstructions and inclusion of parameters calculated and estimated from light response curves, such as dark respiration (Rd), maximum rate of carboxylation of RuBisCO and photosynthetic electron transport allowed the estimation of instantaneous and daily plant photosynthesis. The virtual orchard leaf area index was low, and light was not a limiting factor in early C. canephora development stages. Under such conditions, Robusta assimilated more CO2 at the plant and orchard scale and produced higher total biomass than Conilon. Lower plant daily photosynthesis and total biomass were correlated to higher Rd in Conilon than in Robusta. Among the architectural traits, leaf inclination, size and allometry were most highly correlated with plant assimilation and biomass. Relative allocation in leaf biomass was higher in '19' Conilon than in young Robusta plants, indicating intraspecific biomass partitioning. Similarly, variation in relative distribution of the root biomass and the root volume reflected clonal variation in soil occupation, indicating intraspecific variability in space occupation competitiveness. Coffea canephora denoted high root allocation in both Conilon and Robusta clones. However, relevant differences at subspecific levels were found, indicating the high potential of C. canephora to cope with drought events, which are expected to occur more frequently in the future, because of climate changes. The methodology developed here has the potential to be used for other crops and tree species. Highlights Functional-structural plant model was used to estimate photosynthesis on a plant and daily scales in Coffea canephora (C. canephora). Among the architectural traits, leaf shape and inclination had the most impact on photosynthesis and biomass. Under non-limiting conditions, Robusta had higher plant photosynthesis and biomass than Conilon. A higher leaf biomass allocation in Conilon clone '19' than in Robusta suggested variety-specific partitioning. Variation in the relative distribution of the root biomass indicated C. canephora intraspecific soil occupation variability.

Metabolomic insights of the tomato fruits (Solanum lycopersicum L.) cultivated under different supplemental LED lighting and mineral nutrient conditions

Appropriate adjustment of various microclimatic and nutrient conditions can improve crop productivity under greenhouse cultivation. Here, we performed non-targeted profiling to investigate metabolite variation in tomato fruits following different supplementary LED lighting (SL) (red: R; blue: B; and a combination of red and blue light: RB, for 1 h/day and 6 h/day per condition) and mineral nutrient supply (N, K, Mg). The different SL treatments affected metabolite variation in tomato fruits more significantly than mineral nutrients. Importantly, regulating the SL period induced a more distinct metabolite composition in tomato fruits than that induced by varying the SL sources. Tomato fruits cultivated under RB for 6 h/day had a relatively higher content of sugar derivatives, especially sucrose, thus influencing the gustatory characteristics of the fruit. In contrast, fruit from tomatoes cultivated under RB for 1 h/day showed a distinctive increase in the abundance of amino acids, organic acids, and several secondary metabolites, adding to its nutritional quality. Intriguingly, the different mineral supplements elicited discriminant metabolic variation in tomato fruits cultivated under reduced levels of mineral supply; however, the effects were insignificant under enhanced levels of mineral supply. Specifically, reduced level in nitrogen supply resulted in a lower abundance of amino acids, whereas reduced level in potassium supply increased metabolite levels including amino acids, sugars, and fatty acids in tomato fruits. In the present study, we employed a non-targeted metabolomics approach to unravel the effects of microclimatic parameters and mineral nutrients on fruit quality parameters of tomato plants, by which regulating the period of SL and reducing the potassium concentration were suggested to improve different nutritional qualities.

Plant hormones and nutrient signaling

Plants count on a wide variety of metabolic, physiological, and developmental responses to adapt their growth to variations in mineral nutrient availability. To react to such variations plants have evolved complex sensing and signaling mechanisms that allow them to monitor the external and internal concentration of each of these nutrients, both in absolute terms and also relatively to the status of other nutrients. Recent evidence has shown that hormones participate in the control of these regulatory networks. Conversely, mineral nutrient conditions influence hormone biosynthesis, further supporting close interrelation between hormonal stimuli and nutritional homeostasis. In this review, we summarize these evidences and analyze possible transcriptional correlations between hormonal and nutritional responses, as a means to further characterize the role of hormones in the response of plants to limiting nutrients in soil.

Mineral nutrition in relation to the Norway spruce forest decline in the region Horny Spis (Northern Slovakia)

In this contribution we present the results of analyses of selected mineral nutrients in assimilatory tissues of spruce trees at different developmental phases (plants, adult trees) in the region Horný Spiš. The very close connection between mineral nutrient cycling and other physiological processes in the plants has been well recognised. The presented analyses of mineral nutrient cycling were done within comprehensive eco-physiological research assessing the physiology and health status of spruce stands in the study area. The research was conducted directly in the stand (Hliníky locality, Horný Spiš − two research plots: 1. plot with spruce stand in advanced decline, 2. control plot − without visible decline symptoms) and, at the same time as a pot experiment. The objective of the pot experiment was to verify the supposed negative influence of soil environment (in the locality with advanced decline of spruce stands) on the growth of spruce trees and their mineral nutrient conditions. The analyses of the material sampled from the stands revealed high amounts of manganese (MnT) that were in the toxicity range on both examined plots. Another negative finding was high amounts of toxic aluminium, primarily in needles of adult trees growing on the plot with symptoms of acute stand decline. This reflects a very low value of pH/H<sub>2</sub>O − 3.7 (pH/KCl − 3 to 2.8) and total exhaustion of the soil suffering, moreover, from the lack of soil water. As for the differences in amounts of individual macronutrients between the plot with intensive decline and the control plot, no significant differences were found, with the exception of Fe. On the other hand, evident significant differences in risk elements Pb, Hg and Al were found. As for the differences in nutrient contents in spruce seedlings in the pot experiment (variants 1 to 6), we can see significant differences in macronutrient contents (N, P, Ca, K, Mn), in some cases also in risk element contents (Al).

Rare Earth Elements in Forest-Floor Herbs as Related to Soil Conditions and Mineral Nutrition

Mixtures of rare earth elements (REEs) in fertilizers are widely used in Chinese agriculture to improve crop nutrition. REE concentrations in wild-growing plants, especially herbs, are little known. This study describes differences in the concentrations and proportions of REEs in eight forest-floor herbaceous plants and relates these differences to soil and mineral nutrient conditions. REEs studied were yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu). Leaf concentrations of sum REEs differed more than one order of magnitude between species, being highest in Anemone nemorosa (10.1 nmol/g dry mass) and lowest in Convallaria majalis (0.66 nmol/g) from the same site. Leaf concentrations of all REEs correlated positively (p < 0.001), as did sum REE with calcium (Ca) and strontium (Sr) concentrations (p < 0.001). A negative relationship (r = -0.83, (p < 0.001) was measured between phosphorus (P) concentrations and sum REE concentrations in leaves. However, the proportions of the single REEs in the REE sum differed among species. In A. nemorosa, 57% of the molar REE sum was taken by Y + La, and only 21% by Ce. The other extreme was Maianthemum bifolium, with 37% La + Y and 41% Ce. These two species had 2.7-3.0% of the REE sum as heavier lanthanides, compared to 4.1-5.2% in the six other species. No clear relationship between soil properties or REE contents and leaf REE concentrations was detected. For La, however, an overrepresentation in leaves prevailed throughout all species compared to soils, whereas particularly Nd, Sm, and Tb had a lower proportion in the leaves of all species than in their soils. Possible uptake mechanisms of REEs in plants are discussed.

Fine-root response to nitrogen supply in nitrogen manipulated Norway spruce catchment areas

Investigations were carried out in order to assess the effect of decreased/increased nitrogen (N)- and sulphur (S)-deposition on the growth and vitality if fine-roots of Norway spruce ( Picea abies (L.) Karst.), in three catchment areas within the Lake Gårdsjön basin, SW Sweden. The catchment areas were subjected to decreased N- and S-deposition (G1 ROOF), increased N-deposition (G2 NITREX) and ambient levels of N- and S-deposition (F1 CONTROL). The excavated fine-roots (<1 mm in diameter) were separated into live and dead fractions and chemical analyses were carried out. The proportion of nitrogen to other macro-nutrients in the fine-roots was used as an indicator of mineral nutrient requirements of the forest trees. The most ‘vital’ fine-roots (characterised by high live to dead ratio) were found in all catchment areas in the upper parts of the organic soil horizon, which most frequently exhibited good mineral nutrient and soil water conditions. It was concluded from available climatic data on monthly precipitation and air temperature that the variation in fine-root growth was not caused by climatic changes. The live to dead ratio of the fine-roots gradually decreased with depth and was low in the mineral soil horizon. An increased percentage of living fine-roots in the ROOF catchment suggests an increased ‘vitality’ in fine-roots (increased live to dead ratios), associated with reduced N- and S-deposition. Chemical analyses of live fine-roots in the same area revealed improved mineral nutrient concentrations, e.g. higher Ca/Al ratios, increased concentrations of K, P, Ca and Mg. Fine-root vitality was improved in the NITREX catchment area, probably as a result of an increased cation release. Fine-root distributions, live to dead ratios and mineral nutrient concentrations appear to be strongly affected by N availability in the soil. Increased concentrations of K and P in proportion to N in fine-roots in the ROOF catchment indicate improved mineral nutrient conditions and lower risk of ion-imbalances. The results are in agreement with findings from other investigations suggesting those nutrient deficiencies and/or metal toxicity may strongly affect the growth of fine-roots.

Phosphate uptake kinetics of Artemisia tridentata roots exposed to multiple soil enriched-nutrient patches

Root phosphate (P) uptake capacity in a nutrient-rich soil patch (termed the Primary Patch) was assessed as the rest of the root system was exposed to different mineral nutrient conditions in the form of other nutrient-rich patches (Additional Patches) in a factorial experiment. The experimental design involved different numbers of Additional Patches with different phosphate concentrations, [P i ]. In addition to testing the effect of the total quantity of added P on root uptake capacity in the Primary Patch, the influence of the distribution of the added P was also tested. The [P i ] and number of Additonal Patches were chosen such that the total quantity of P added was the same among some treatments which afforded a test of the influence of the concentration and distribution of Additional Patches on the uptake capacity of the roots in the Primary Patch. As the number and the concentration of Additional Patches increased, the upake capacity of Primary Patch roots was expected to be reduced relative to roots from untreated Control Patches. Averaged across all treatments, roots from the Primary Patch exhibited greater uptake capacities than the Control Patch roots (i.e., roots from unamended soil). With substantial enrichment of P i in the Additional Patches, the uptake capacity of roots was reduced in both the Primary and Control Patch roots. However, the concentration and number of Additional Patches had no clear influence on P uptake capacities in the Primary Patch. The P uptake capacity of roots from the Additional Patches with low and moderate [P i ] did not differ from the uptake capacity of roots in the Control Patches. However, for roots in the Additional Patches with high [P i ] (equivalent [P i ] to that of the Primary Patch) the uptake capacities were significantly greater that those of the Control Patch roots. In an ancillary P acquisition experiment, plants procured less P from the Primay Patch if there were four Additional Patches than if there were only two Additional Patches. This suggests that P acquisition occurred in the Additional Patches and that regulation at the whole-plant level reduced the uptake of P from the Primary Patch. In contrast, the root uptake kinetics did not seem to be as responsive to added P i presented in the Additional Patches.

Elevated CO 2 alters community-level physiological profiles and enzyme activities in alpine grassland

Plots of an alpine grassland in the Swiss Alps were treated with elevated (680 μl l −1) and ambient CO 2 (355 μl l −1) in open top chambers (OTC). Several plots were also treated with NPK-fertilizer. Community level physiological profiles (CLPPs) of the soil bacteria were examined by Biolog GN microplates and enzyme activities were determined through the release of methylumbelliferyl (MUF) and methylcoumarin (MC) from MUF- or MC-labelled substrates. A canonical discriminant analysis (CDA) followed by multivariate analysis of variance showed a significant effect of elevated CO 2 on the CLPPs both under fertilized and unfertilized conditions. Further, the installation of the OTCs caused significant shifts in the CLPPs (chamber effect). Of the four enzyme activities tested, the β- d-cellobiohydrolase (CELase) and N-acetyl-β- d-glucosaminidase (NAGase) activity were enhanced under elevated CO 2. l-Leucin-7-aminopeptidase (APEase) activity decreased, when the plots received fertilizer. β- d-Glucosidase (GLUase) remained unaffected. The results suggest effects of elevated CO 2 on specific microbial activities even under low mineral nutrient conditions and when bulk parameters like microbial biomass or respiration, which have been investigated on the same site, remain unaffected. The observed medium-term changes point at possible long-term consequences for the ecosystem that may not be specified yet.

Changes in wheat seed storage protein fingerprint due to soil mineral content

Wheat seed storage protein fingerprint is used to determine the gluten protein pattern in studies aimed at improving flour quality. Wild wheat with high seed protein content is used extensively in wheat breeding programs. Although the wild wheat growth and protein content may be influenced by environmental conditions, the gluten-protein pattern is generally considered as indicative of a genotype, without the superimposition of environmental influences. The effects of soil type, habitat, and deficiencies of N, P, K and S on seed storage protein composition were examined in nine accessions of wild wheat (Triticum turgidum var. dicoccoides) and three varieties (two T. aestivum and one T. durum). Soil from ten natural habitats of the wild wheat that had not previously received any fertilizers or manures was sampled and used to grow wheat in a greenhouse. Seed storage protein composition was characterized by SDS-PAGE. Although deficiencies in soil nutrient caused variations in the seed storage proteins, the genotype was the main factor determining the seed storage protein composition. Seed storage protein composition of genotypes varied when grown under different mineral nutrient conditions. Only one genotype was stable showing almost identical protein patterns under all growing conditions studied without any qualitative change in fingerprint pattern. In the other genotypes, as well as the cultivars, the seed storage protein was affected at least to some extent by the soil. The ‘soil effect’ is summarized in terms of three main quantitative changes in the seeds: 1 – the relative amounts of the high-molecular-weight proteins; 2 – the relative amounts of proteins in the range of 45 and 65 kD; 3 – the percentage distribution of the HMW glutenin and other groups of seed storage proteins. The soild induced also qualitative differences in the composition of seed storage proteins, mostly in those of 45–65 kD. These differences were observed whenever a deficiency of S, N, P, K or Mg was identified. Therefore, in breeding programs that use seed storage protein fingerprints of wild wheat germplasms should be exercise caution when the germplasms selected from wild habitats.

Changes in the element composition of globoids from Cucurbita maxima and Cucurbita andreana cotyledons during early seedling growth

Energy dispersive X-ray analysis was used to study the element composition of globoids from the cotyledons of Cucurbita maxima and Cucurbita andreana seeds and seedlings at various stages of growth. The influence of light and mineral nutrient conditions on changes in globoid composition was also investigated. The element composition of globoids changed markedly during early seedling growth. In both species, regardless of light and mineral nutrient conditions, K decreased markedly, Mg, Ca, Fe, Mn, and Zn generally increased, and P remained relatively constant. There were differences in globoid composition changes between the two species that could be attributed, at least in part, to differences in the Ca content of the mature, dry embryos. In C. andreana, which had a higher initial Ca content, there was a large increase in the Ca content of the globoids during seedling growth and no significant increase in Mn. In C. maxima globoids, there was only a slight increase in Ca, but there was a much larger increase in Fe, Zn, and Mn than occurred in C. andreana. Light conditions alone did not have a significant influence on the changes in globoid composition. Light, in combination with mineral nutrients, resulted in a more rapid degradation of globoids in the later stages of growth. Mineral nutrient conditions affected mostly elements that were initially present in large amounts. There were very large, globoid-like particles present in some later stage samples of both species, from each of the different growth conditions. These particles had element compositions that were consistent with their being composed of phytate. Keywords: Cucurbita, energy dispersive X-ray analysis, globoids, mineral nutrient reserves, large particles.

Effect of living roots on soil organic matter decomposition

Published information is contradictory about the inhibitory or stimulatory effect of living roots on soil organic matter decomposition. In this study, 14C-labelled rye straw was exposed in fertilized or unfertilized soil with or without plants (winter rye, Secale cereale) for 49 days under semi-controlled conditions. Our objective was to study the effect of roots on soil organic matter mineralization under different mineral nutrient conditions. The planted treatment had a higher 14CO 2 loss and a higher efficiency of 14C-labelled material utilization by microorganisms. Fertilization decreased 14CO 2 loss. Percent 14C in microbial biomass was positively correlated with percent 14C respired. Total microbial biomass, 14C-labelled microbial biomass and total 14C remaining of the rhizosphere soil were higher compared to bulk soil. Living roots had a stimulatory effect on soil organic matter decomposition due to the higher microbial activity induced by the roots. This stimulatory effect was reduced by application of fertilizer.

A comparison of growth responses of Douglas fir and Sitka spruce to different nitrogen, phosphorus, and potassium levels in sand culture

Douglas fir and Sitka spruce seedlings were grown in sand culture under controlled mineral nutrient conditions. Nitrogen, phosphorus, and potassium supply levels were varied one nutrient at a time in three separate experiments. The relative growth rate (RGR) of Sitka spruce was found to be higher than that of Douglas fir at high levels of N and K supply, although in all treatments the total dry matter production of Douglas fir was greater than that of Sitka spruce after 95 days. At low levels of P supply the RGR of Douglas fir was greater than that of Sitka spruce.Effects of treatment on RGR were apparently achieved mainly by their effect on net assimilation rate, but leaf weight ratio also showed a small, and significant, response to treatment.

THE NITROGEN METABOLISM OF PICEA GLAUCA (MOENCH) VOSS AND PINUS BANKSIANA LAMB. AS INFLUENCED BY MINERAL NUTRITION

White spruce (Picea glauca (Moench) Voss) and jack pine (Pinus banksiana Lamb.) seedlings were grown in sand cultures by Swan (who reported on their growth in 1960) and they were irrigated with full nutrient solution high in sodium, or solutions deficient in each of several nutrients. Responses characteristic of the following six treatments were studied: full nutrient but with low sodium; nitrate or ammonium as the sole source of nitrogen; low nitrogen; low phosphorus; and low potassium. When shoot elongation had ceased, extracts of seedling parts (leaves, stems with buds, and roots) were examined by paper-chromatographic methods for free nitrogenous compounds.In leaves, the relative proportions of nitrogenous compounds in spruce and pine differed from those in the stems and roots. Nutrient deficiency and the form of nitrogen available affected both the total amount and relative composition of the soluble nitrogen. Under better mineral nutrient conditions, arginine accumulated while amide (glutamine) remained low. The accumulation of a number of compounds resulting from nutritional deficiency, for example glutamine, with low potassium, indicated that blocks occurred in metabolic pathways. Ammonium nitrogen was shown to foster arginine and amides (especially in spruce) and to lead to a large increase of free guanidino compounds which hitherto have passed unnoticed. By contrast, in leaves nourished by nitrate as the sole source of nitrogen, guanidino compounds were less prominent. Under the conditions of reduced growth and protein synthesis brought about by specified nutrient deficiencies, many unidentified compounds, which were not known intermediates of the ornithine or urea cycle, appeared.The present study dealt with observations made at one season of the year (late summer) and does not preclude the occurrence of somewhat different responses which might have been observed at other times of the year.