Tissue Nutrient Concentrations Research Articles

Phenology Based Variability of Tissue Nutrient Content in Mature Muscadine Vines (Vitis rotundifolia cv. Carlos)

Muscadine (Vitis rotundifolia) is a grape species that is native to the Southeastern US, where several cultivars are grown commercially for processing or direct consumption. Phenology based tissue analysis to determine the nutritional status of a vine is a critical tool for growers to understand fertilizer demands in a vineyard. For European-style wine grapes, tissue sampling for nutrient content is well researched. However, current tissue sampling recommendations for muscadines are solely based on anecdotal knowledge. It is currently unknown if the type of tissue collected has an impact on variability and content of nutrients. Questions also remain as to whether or not seasonal vine phenology impacts tissue nutrient content. Without this knowledge it is difficult for a muscadine grower to make informed decisions on the nutritional status of a muscadine vine. Therefore, we investigated the impact of the phenological vine stage (bloom, fruit set, véraison) on nutrient content in two different tissue types (mature leaf vs. petiole), sampled at two different positions on a muscadine vine (opposite of cluster vs. shoot). The study was conducted over two growing seasons (2019 and 2020) in a commercial mature muscadine vineyard (‘Carlos’). Our results show that over both study years, the highest variability in nutrient content was found during bloom (May–June), while nutrient variability was lower during fruit-set and veraison. We also found fully mature leaf samples showed a lower variability in nutrient tissue content. Based on our results, sampling fully mature leafs from shoots remains the best practice. However, our results also indicate that tissue sampling later in the season might be a better practice, compared to the current practice of taking samples during June.

Comparing Crop Yield, Secondary Metabolite Contents, and Antifungal Activity of Extracts of Helichrysum odoratissimum Cultivated in Aquaponic, Hydroponic, and Field Systems.

The overexploitation of wild plants for medicinal uses and conventional agricultural farming methods, which use high amounts of water, fertilizers, and pesticides, have had devastating environmental consequences. This study aimed to evaluate the prospects of using aquaponics and hydroponics as alternative approaches to soil cultivation by comparing the crop yields, secondary metabolite contents, and the antifungal activities of ethanol extracts of Helichrysum odoratissimum (L.) Sweet, a widely used medicinal plant species in Southern Africa. Six-week-old H. odoratissimum seedlings were grown in aquaponic and hydroponic systems. The growth parameters, secondary metabolite contents, and antifungal activity against Fusarium oxysporum were assessed. The results for crop yield (plant height, fresh and dry weights) and the tissue nutrient contents did not change substantially (p > 0.05) between aquaponic and hydroponic treatments. Gas chromatography–mass spectrometry (GC–MS) analysis showed that monoterpenes and sesquiterpenes were the most abundant compounds in H. odoratissimum; however, no statistical difference was observed among the field, hydroponic, and aquaponic plants (DF = 2; χ2 = 2.67; p > 0.05). While there was no significant difference in polyphenol contents among the three treatments, remarkably, the flavonol contents in the leaves varied significantly (DF = 2; χ2 = 6.23; p < 0.05) among the three treatments. A higher flavonol content occurred in leaves from the hydroponic system than in leaves from the aquaponic (p < 0.05) and field (p > 0.05) systems. The MIC results showed that the ethanolic extract of H. odoratissimum was fungistatic against F. oxysporum; however, this effect was more prominent in the ethanol extracts of plants grown in the aquaponic system, with a mean MIC value of 0.37 ± 0.00 mg/mL The key findings of this study are that aquaponically cultivated plants exhibited the best antifungal activity, while higher total flavonol contents occurred in the hydroponically cultivated plants. In conclusion, aquaponics and hydroponics performed better or similar to field cultivation and are viable alternative methods for cultivating H. odoratissimum plants.

Nutrient Management of Shallot Farming in Sandy Loam Soil in Tegalrejo, Gunungkidul, Indonesia

The serious problems of sandy soils for crop development are low water-holding capacity, nutrient retention, and low content of all nutrients. The objective of the study was to increase the nutrient content of sandy soil and evaluate nutrient types that mostly affect the high shallot yield with reasonable economic values. The field experiment was conducted on the upland sandy loam soil. Six treatments consisting of complete nutrients, N-, P-, K-, Mg- and S-omission tests were arranged in a randomly completed block design with four replicates. The observed parameters included soil physicochemical properties, tissue nutrient content, growth, yield, and input-output of shallot cultivation. The results showed that N, P, K, Mg and S application successfully increased shallot bulb, achieving 11.43 t ha−1 on sandy soil. The order of shallot tissue content was K &gt; N &gt; P~Mg &gt; S, where the S, P, N, and Mg are limiting factors, as revealed by significantly lower relative yield (varying from 79 to 88%). The highest weight loss during storage occurred for S-omission treatment (40 to 60%), indicating insufficient S tissue is the most responsible for the quality of shallot. The complete nutrient treatment gave the highest income (7446.09 USD ha−1) with a revenue cost ratio of 2.41 compared to other treatments. The tolerance limit for price reductions that do not cause losses was 58.59%.

Coordination among Water Transport, Photosynthesis and Nutrition under Climate Change: Stronger Responses of a Native than an Invasive Herb

Climate change will impact all plant physiological processes including water transport, photosynthesis, and nutrient assimilation. How these processes are coordinated in response to climate change is not fully understood. Here we tested how these processes will respond to elevated CO2 concentration ([CO2]) and temperatures for two herbaceous species (an invasive and a native Eupatorium species in East Asia; family Asteraceae) and whether these processes are coordinated using a controlled experiment. We also investigated the differences between these two species, and the structural basis for changes in physiology. Leaf photosynthetic capacity (Amax, measured under ambient conditions) increased significantly in the native species, while that of the invasive species did not change under elevated [CO2] and temperatures. The leaf hydraulic conductance (Kleaf) of both species tended to increase under elevated temperatures and [CO2], with that of the native species increasing to a greater extent. Changes in Kleaf and Amax were coordinated, and Kleaf was closely associated with leaf minor vein density across treatments. The increased photosynthetic capacity of the native species was probably related to an increased N investment in photosynthesis; its leaf N decreased but chlorophyll concentration increased inviting detailed studies in N partitioning. No coordination between water use (water transport, stomatal conductance, and water use efficiency) and leaf tissue nutrient (N, P) concentrations was found, probably owing to the active control in nutrient uptake. Thus, photosynthesis is coordinated with water transport in response to climate change, while the coordination between water use and nutrient accumulation can be absent due to active control. Our results also suggest that global climate change will not necessarily fuel more positive responses in invasive plants than native plants.

Crescimento e qualidade de cebolinha em sistema hidropônico com concentrações de sulfato de magnésio

ABSTRACT Chives are popular herbs, and highly appreciated by consumers. The experiment was conducted in the period from September to November 2020 in a greenhouse, located at the Federal University of Technology, Paraná, Brazil. This study aimed to evaluate the growth, physiological responses, and quality attributes of chives grown in hydroponic systems containing different concentrations of magnesium sulfate. The experimental design was randomized blocks, and the treatments consisted of a standard solution with the addition of magnesium sulfate at the following doses (g/L): standard solution 0.4; 0.42, 0.44; 0.46, and 0.48, with four repetitions per treatment. The analyzed variables were physiological indicators and growth; physical-chemical characteristics and nutrient content in tissues. The dose of 0.48 g/L resulted in the highest number of leaves (47.3) and contributed to 44% reduction in leaf drop, thereby positively influencing growth with higher fresh mass (231.40 g/plant). The relative chlorophyll index (58.64) obtained at 0.48 g/L dose revealed an increase in the chlorophyll content and, consequently, in the green color of the plants, with °hue angle of 140.54. Greener leaves is a visual aspect preferred by consumers. In addition, the higher concentration of magnesium sulfate provided 50.7% increase in the content of soluble solids and 50.6% rise in phenolic compounds. The dose of 0.48 g/L magnesium sulfate contributed to reduced leaf fall, improved visual appearance, greater bioactive compounds, and enhanced leaf sweetness to meet the quality standards that consumers expect for this condiment.

Micronutrient content and accumulation in leaves and bunches of black pepper during two crop cycles

A comprehensive knowledge about micronutrient dynamics in leaves and bunches of black pepper is needed in order to proper diagnose nutrient needs, and thus facilitate fertilization management. This study aimed to evaluate micronutrient concentration and accumulation in leaves and bunches of black pepper bunches to understand the crop nutritional demand. The experiment was carried out on in a commercial field of Piper nigrum ‘Bragantina’ located in São Mateus, Espírito Santo, Brazil. Composite samples of leaves and bunches were taken periodically during two crop cycles and the concentration of Fe, Zn, Mn, Cu, and B were assessed. The micronutrient accumulation curves behaved linearly and quadratically, reaching the maximum accumulation point during the time of harvesting. Fe, Mn and B were the micronutrients with highest concentration in both bunches and leaves of black pepper. The nutrient concentration in leaf tissues varied seasonally. These results may contribute to a more sustainable agriculture, in which fertilization rates should consider different needs through the crop stage.

Correlations among nutrient contents in soil, leaf, and fruit tissues and yield of Olea europaea L. cv. Arbequina in the South of Brazil

The objective of the work was to relate the nutritional status of olive orchards from the central region of the Rio Grande do Sul with fruit yield and identify unadjusted points in the fertilization recommendation system to be improved. Soil, leaf, and fruit samples were taken from eight orchards, between 2018 and 2020, and were evaluated for the contents of N, P, K, B, pH, TOC, Al+3, and soil texture. The 20-40 cm layer in soil showed acidity and Al+3 content at potentially restrictive levels. The available P and B contents in soil were considered low. In leaf tissue, K and N presented high contents. The correlations revealed that fruit yield was limited by high N contents on leaves, especially in winter. B content in fruits diminished in higher soil pH, suggesting that the B threshold value in soil for olives in the south of Brazil should be pH-dependent.

Evaluation of real-time nutrient analysis of fertilized raspberry using petiole sap.

The time delay in receiving conventional tissue nutrient analysis results caused red raspberry (Rubus idaeus L.) growers to be interested in rapid sap tests to provide real-time results to guide immediate nutrient management practices. However, sap analysis has never been conducted in raspberry. The present work aimed to evaluate the relationship of petiole sap nitrate (NO3–), potassium (K+), and calcium (Ca2+) concentrations measured using compact ion meters and leaf tissue total nitrogen (TN), potassium (K), and calcium (Ca) concentrations measured using conventional tissue nutrient analysis. The relationship of petiole sap NO3– and leaf tissue TN concentrations with plant growth and production variables was also explored. Fertilizer treatments of urea were surface applied to raised beds of established “Meeker” floricane red raspberry plots at control, low, medium, and high rates (0, 34, 67, and 101 kg N ha–1, respectively) in 2019 and 2020. The experiment was arranged in a randomized complete block design with three replications. Whole leaves were collected from representative primocanes in mid- and late- July and August 2019 and 2020 (i.e., four sampling time points per year). At each sampling time point, a subsample of leaves was used for petiole sap analyses of NO3–, K+, and Ca2+ concentrations using compact ion meters, and conventional tissue testing of leaf tissue TN, K, and Ca concentrations, respectively. There were no interactions between N fertilizer rate and year nor between N fertilizer rate and sampling time. No significant differences were found due to N fertilizer rate for petiole sap NO3–, K+, Ca2+ nor leaf tissue TN, K, Ca concentrations. However, significant year and sampling time effects occurred in measured petiole sap and leaf tissue nutrient concentrations. Overall, the correlations between petiole sap NO3– and leaf tissue TN, petiole sap Ca2+ and leaf tissue Ca, petiole sap K+ and leaf tissue K concentrations were non-strong and inconsistent. Future research is warranted as the interpretation of correlations between raspberry petiole sap and leaf tissue nutrient concentrations were inconclusive.

Detection of calcium, magnesium, and chlorophyll variations of wheat genotypes on sodic soils using hyperspectral red edge parameters

Plants grown on sodic soils can suffer from macronutrient deficiencies, such as calcium (Ca), magnesium (Mg), and potassium (K), reducing health and growth. Nutrient concentrations in plant tissue could potentially provide a signal to identify cultivars tolerant to sodic conditions. However, conventional approaches to diagnosing crop nutrient and chlorophyll status involve determining total elemental content in plant tissues. These methods are time-consuming, tedious, and expensive, requiring destructive sampling of plant parts and complex laboratory analyses. Here, we propose a novel approach using hyperspectral sensing to determine macronutrient and chlorophyll variations/deficiencies of 18 different wheat genotypes grown in moderately sodic (MS) and highly sodic (HS) soil conditions in north-eastern Australia. Canopy reflectance was measured using a handheld spectroradiometer close to flowering to compute red edge spectral indices, such as normalized difference red edge index (NDRE), red edge inflection point (REIP), and red edge chlorophyll index (Cl rededge). Plant Ca, Mg, and K concentrations were also measured by destructive sampling of young mature leaves followed by laboratory analysis. The maximum first derivative of reflectance spectra for 18 wheat genotypes were observed at 722–728 nm and 719–725 nm for the MS and HS site, respectively and was used to determine REIP for the genotypes using a four-point linear interpolation method. Ca and Mg had a significant positive association with both REIP and NDRE, with Ca more closely correlated than either Mg or K. REIP was more closely associated with Ca (R2=0.72; RMSE=0.02 for the MS site and R 2=0.57; RMSE=0.02 for the HS site) than NDRE. This suggests that REIP has a great potential to detect structural variations of wheat genotypes in sodic soil environment. Furthermore, Ca was also significantly (p<0.0001) and positively correlated with Cl rededge at both sites with R2=0.53 and 0.51 for the MS and HS site. This suggests that plant structural variations in sodic soil can regulate leaf chlorophyll concentration and, in turn, photosynthetic activities. Overall, results demonstrate that hyperspectral sensing can be efficiently used to detect plant Ca, Mg, and chlorophyll concentrations. The study improves understanding of genotypic nutrient variation for tolerance to different levels of sodic soil conditions using optical properties of plant structure and can be beneficial to the plant science community for developing new approaches to study plant physiology.

The Multifarious Endophytic Actinobacterial Isolate, Streptomyces tubercidicus UAE1, Combined With the Seaweed Biostimulant Further Promotes Growth of Avicennia marina

Mangrove (Avicennia marina) is a “green lung” tree growing along the Arabian Gulf coastline in the United Arab Emirates. Here, we aimed to determine the impact of the application of a commercial seaweed extract (SWE) biostimulant and endophytic actinobacterial isolates on growth performance and endogenous hormonal levels of mangroves. Therefore, we isolated endophytic plant growth-promoting (PGP) actinobacteria (PGPA) from mangrove roots and evaluated their potential as biological inoculants on mangrove seedlings under greenhouse and open-field nursery conditions. Seven salt-tolerant isolates had the ability to produce different levels ofin vitroplant growth regulators (PGRs) and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase (ACCD) and to solubilize phosphorus. Accordingly, only one isolate,Streptomyces tubercidicusUAE1 (St), was selected based on its relative superiority in displaying multiple modes of action and in successfully colonizing mangrove tissues for 15 weeks. In the greenhouse experiments, plants treated withStand SWE significantly (p&amp;lt; 0.05) improved dry biomass by 40.2% and 55.1% in roots and 42.2% and 55.4% in shoots, respectively, compared to seawater-irrigated non-treated mangrove plants (control). However,St+SWE caused a greater significant (p&amp;lt; 0.05) increase in dry weight of roots (67.6%) and shoots (65.7%) than did control plants. Following the combined treatment ofSt+SWE,in plantaPGR levels were found to be greatly enhanced over the non-treated control plants grown in non-SWE supplemented sediments, or plants inoculated with onlySt without the supplementation with SWE,or with non-inoculated plants grown in sediments supplied with SWE only. This was evident from the significant (p&amp;lt; 0.05) increases in the photosynthetic pigments and production of PGRs, as well as the reduction in the endogenous ACC levels of plant tissues compared to those in other treatments. Tissue nutrient contents of seedlings also increased by at least two-fold inSt+SWE treatment as compared to control. Similar effects were observed on all growth parameters under natural open-field nursery conditions. CombiningStwith SWE not only stimulates plant growth but also potentially has additive effects on mangrove ecosystem productivity in nutrient-impoverished soils in the Arabian coastal areas. This report is the first in the field of marine agriculture that uses SWE as a nutrient base for actinobacteria capable of producing PGRs and ACCD.

Nutrición in vitro de anturio (Anthurium andreanum Linden var. Tropical) en tres sistemas de cultivo

Anthurium is a very important ornamental plant in the market. However, its traditional reproduction presents problems, therefore in vitro culture represents an alternative for its propagation. In the in vitro plant tissue culture, the nutrients are provided by the media, but information on the in vitro nutrition for anthurium is scarce. The objective of this research was to evaluate plant growth characteristics, nutrient content in plant tissues and nutrient removal from the culture medium in three in vitro culture systems: semi-solid, partial immersion and the RITA® bioreactor. The data were analyzed, using an ANOVA and compared with Tukey tests, using the statistical software R-STUDIO. The highest length of shoots and roots were observed with partial immersion; the number of leaves, shoots and roots did not show differences with the RITA® bioreactors. The highest tissue content of nutrients occurred in plants cultivated in the RITA® bioreactor. For the content of nutrients in the culture medium, the highest one was observed in the RITA® bioreactor, which indicates a most efficient use of nutrients, due to the greater contact of explants with the media and a best gas exchange. Therefore, the RITA® bioreactor represents the most viable option for anthurium plants production.

Plant Tissue Nutrient Concentration and Major Soil Nutrients Influenced by NPSB Fertilizer Rates and Plant Population of Maize (Zea Mays L.) at Bako, Oromia National Regional State

Plant nutrients such as nitrogen, phosphorus, potassium and sulfur are the nutrients frequently limit the yields of maize over the world. Nutrient recommendation should be based on the optimum yield and environmental save that can be through plant tissue analysis and soil test. This experiment was conducted at Bako Agricultural Research Center west region of Ethiopia Gobu Sayo using split plot desighn with three levels of plant population 53.333,66,666 and 76,923 plants per hectare on main plot and five level 0,100,150,200,250 kg/ha of NPSB fertilizer rates on sub-plots. Soil sample was taken from the plots pre-harvesting for composite sample and post-harvest from each plot and analyzed at Bako soil laboratory and Ethiopia water work design Addis Ababa for soil fertility management. Nutrient in plant tissue was analyzed at Holota Agricultural Research Center soil laboratory. Collected data was analyzed using Genstat computer statistical soft-ware package. The result of pre planting soil analysis showed soil of the study area was categorized as clay soil with medium and stable organic matter and low organic carbon and low total nitrogen that shows low soil fertility. The ANOVA result showed addition of fertilizer reduced soil pH from 5.7 to 5.47 and bellow. 150 kg/ha of NPSB which gave economically feasible yield 9460kg/ha moderately acidified the soil. This soil analysis result showed that the level at which fertilizer boost yield of maize. Only percent of phosphorus was changed due to plant population density. Plant tissue concentration at silking was significantly influenced by fertilizer rates. Potassium is at sufficiency range for all level of supplied fertilizer. Sufficient range nitrogen at silkin was recorded from the plot received 100-150 kg/ha which gave economically feasible yield. It is better to use fertilizer rate of 150kg/ha which shows sufficiency range for nutrient concentration of soil and plant tissue in leaf at silking stage. This finding is not the end for the area and further research should be carried out for feature. Keywords: plant tissue, soil, Zea mays L., Nitrogen, Phosphorus, Sulfur, potassium DOI: 10.7176/JBAH/12-13-04 Publication date: July 31 st 2022

Effects of dual mycorrhizal inoculation on Pinus strobus seedlings are influenced by soil resource availability

PurposeMycorrhizal interactions can drive plant productivity, diversity, and ecosystem function; however, gaps remain in our understanding of interactions among plants and different mycorrhizal types. Species in the Pinaceae primarily associate with ectomycorrhizal (ECM) fungi; however, some species can be colonized by arbuscular mycorrhizal (AM) fungi as rudimentary hosts. Interactions between plants and mycorrhizal fungi are expected to change along the mutualism-parasitism spectrum with changes in resource availability; however, the impacts of AM fungi on rudimentary hosts under different resource conditions are unknown.MethodsIn this study, we assessed the individual and interactive effects of ECM and AM inoculation on Pinus strobus seedlings under factorial combinations of low, medium, or high nitrogen (N) and phosphorus (P) supply.ResultsNo AM colonization was observed at the end of the experiment; however, seedlings inoculated with AM fungi showed significantly reduced growth. AM inoculation also had the greatest effect on P. strobus tissue nutrient concentrations under low fertilization including increased P and reduced N and N:P ratio. ECM colonization benefited P. strobus growth and P uptake, especially under low P availability, but ECM colonization rate itself was limited by low P. ECM colonization also improved seedling regulation of N:P ratio near optimum compared to uncolonized seedlings.ConclusionWe conclude that the effects of ECM and AM inoculation on P. strobus are context dependent, which is important for understanding mutualistic and rudimentary host responses and may have important implications for regeneration and early growth of P. strobus in natural and managed forests.

Defoliation-induced changes in foliage quality may trigger broad-scale insect outbreaks

Top-down effects, like predation, are drivers of insect outbreaks, but bottom-up effects, like host nutritional quality, also influence outbreaks and could in turn be altered by insect-caused defoliation. We evaluated the prediction that herbivory leads to a positive feedback on outbreak severity as nutrient concentration in plant tissues increases through improved soil nutrient availability from frass and litter deposition. Over seven years of a spruce budworm outbreak, we quantified litter nutrient fluxes, soil nitrogen availability, and host tree foliar nutrient status along a forest susceptibility gradient. As the outbreak progressed, both soil nutrient fluxes and availability increased which, in turn, improved foliage quality in surviving host trees. This is consistent with boosted insect fitness and increased population density and defoliation as outbreaks grow. Our results suggest that a positive bottom-up feedback to forest ecosystems from defoliation may result in conditions favorable to self-amplifying population dynamics in insect herbivores that can contribute to driving broad-scale outbreaks.

Consorcios microbianos aplicados en un sistema de producción de plántulas de aguacate cultivar “Criollo”

The application of microbial consortia in a production system of avocado seedlings (Persea americana Mill.) cultivar ‘Criollo’ was evaluated and as well as its incidence in the development and nutritional status of the seedlings. Four treatments were evaluated, arranged in a completely randomized block design (DBCA). The seeds used in the trial were sown in sterile substrate (organic soil and perlite; 3:1) placed in nursery bags (polyethylene, capacity: 2.2 kg). Microorganism inoculations (Glomus spp, Trichoderma spp., Bacillus spp., Pseudomonas spp.) were performed at 70, 100, 120 and 150 days after sowing (DAS). The variables plant height, stem diameter and greenery index were evaluated throughout the trial (80, 110, 140 and 170 DAS); while at the end of the trial (170 DAS) the concentration of nutrients in tissue and dry matter of stems, leaves and roots were evaluated. Statistically significant differences were obtained at 170 DDS for the variables: plant height, stem diameter and greenery index; the analysis of tissue nutrient concentration reported values ​​within the parameters appropriate for the species and an increase in Cu concentration. This investigation evidenced the favorable effect of the microorganisms evaluated in the development of the seedlings, as well as the assimilation of nutrients.

Investigating Nutrient Supply Effects on Plant Growth and Seed Nutrient Content in Common Bean.

Low soil fertility commonly limits growth and yield production of common bean (Phaseolus vulgaris L.) in tropical regions. Impacts of nutrient limitations on production volume are well studied and are a major factor in reducing crop yields. This study characterised the impact of reduced nutrient supply on carbon assimilation and nutrient content of leaf, phloem sap and reproductive tissues of common bean grown in a controlled environment in order to detect chemical markers for changes in nutritional content. Leaf gas exchange measurements were undertaken over plant development to characterise changes to carbon assimilation under reduced nutrient supply. Samples of leaf, phloem sap and pod tissue of common bean were analysed for carbon isotope discrimination, mineral nutrient content, and amino acid concentration. Despite declines in nutrient availability leading to decreased carbon assimilation and reductions in yield, amino acid concentration was maintained in the pod tissue. Common bean can maintain the nutritional content of individual pods under varying nutrient availabilities demonstrating the resilience of processes determining the viability of reproductive tissues.

Inter-specific competition between finger millet and Guinea grass for growth and nutrient uptake under nutrient-limited conditions

ABSTRACT Crop–weed interactions in nutrient-deficient environments can induce strong intra- and inter-specific competition for such nutrients. The study investigated nutrient uptake by finger millet (FM; Eleusine coracana (L.) Gaertn.) in the presence of the upland weed, Guinea grass (GG; Panicum maximum Jacq), under nutrient-limited conditions. A pot experiment was conducted with different neighbor-densities of the two species, including monocultures and mixed cultures. The effects of inter-specific/intra-specific competition on nutrient uptake and growth of the two plant species were measured. Varied plant combinations impacted on plant dry weight, uptake, and use efficiency of nitrogen, phosphorus, and potassium by FM. Root and shoot dry weights of FM were markedly reduced in the presence of GG compared to that when neighbors were from the same species. The largest reduction of tissue nutrient concentration of FM was recorded in FM:GG plant combination of 1:2. The results indicated that the growth and nutrient uptake of FM was suppressed when it co-existed with GG due to strong inter-specific competition under nutrient-limited conditions. GG maintained similar biomass irrespective of the fertilizer treatment and plant combinations, demonstrating its ability to outcompete neighboring species when resources are limited in the growing environment. The present study also provides scientific evidence that GG is well adapted to nutrient-poor environments, which is attained through enhancing the use efficiency of limited nutrients in biomass formation. This might have helped GG to gain the competitive advantage over other plants in the same habitat and dominate in most agro-ecological systems as an invasive weed species.

Reduced Nitrogen Fertilizer Rates Maintained Raspberry Growth in an Established Field

Optimizing nitrogen (N) fertilizer rates maintains good red raspberry (Rubus idaeus L.) production while alleviating environmental risks. Although raspberry growers in Washington are using the caneberry nutrient management guides derived from western Oregon, these guides may not be appropriate for other production regions given the differences in climate, soil type, and crop productivity. However, limited research has been conducted to observe the impact of the N fertilizer rate on floricane red raspberry growth, yield, and fruit quality in Washington. The aim of this study is to evaluate the response of “Meeker” floricane red raspberries grown in northwest Washington, USA, to different N fertilizer rates in order to provide information for future local nutrient management guides. Treatments of urea (46% nitrogen (N)) were surface-applied to raised beds of established ‘Meeker’ raspberry plots at controls, low, medium, and high rates (0, 34, 67, and 101 kg N ha−1, respectively) in 2019 and 2020. The experiment was arranged in a randomized complete block with three replications. Fruit yield and quality, plant growth and leaf tissue nutrient concentrations, and soil characteristics were evaluated. There were no N fertilizer rate treatment effects for the yield, fruit quality, plant growth, leaf tissue nutrient concentrations, and soil characteristics, except for fruit titratable acidity and soil ammonium (NH4-N) concentrations. The lack of a plant response may be due to nutrients mineralized from soil organic matter (3.81–4.0%) and the utilization of plant nutrient reserves. Based on the results, the soil organic matter level and plant nutrient reserves should be considered when making nutrient management suggestions. Fertilizer costs as well as the potential for environmental pollution from excess fertilizers could be reduced through utilizing these two potential sources of nutrients. Furthermore, longer periods of research is warranted to understand how to adjust N fertilizer rates based on plant and soil characteristics while sustaining yields.

Boron deficiency affects ATP hydrolysis of plasma membrane and nutrients uptake in coffee: Consequences for plant growth

Boron (B) shapes the plasma membrane structure and modulates the plasma membrane H+-ATPase activity stimulating nutrients uptake by the plant root system. However, the influence of B-nutritional status on plasma membrane H+-ATPase activity of some plants remains unclear, especially in dicots with higher B requirement, such as coffee. This study investigated the effects of B-nutritional status on ATP hydrolysis of plasma membrane and nutrients uptake in coffee. Coffee seedlings were grown in substrate with six B levels (0.1, 0.2, 0.4, 0.6, 0.8 and 1.0 mg dm−3, as H3BO3) for 153 days and plasma membrane H+-ATPase activity was evaluated in the roots, as well as nutrient concentration and accumulation in leaf tissues and plant growth. The B nutritional status greatly influenced plasma membrane H+-ATPase activity in roots. At 1.0 mg dm−3, the ATPase hydrolysis activity was six times greater and H+ transport two times higher compared to the lowest level of 0.1 mg dm−3. The B supply increased significantly leaf concentrations of B, K, P, Mg, and Ca; nevertheless, accumulation of these nutrients did not vary in the leaves because leaf biomass decreased at high B levels.

Spatial approach for diagnosis of yield-limiting nutrients in smallholder agroecosystem landscape using population-based farm survey data.

Adept use of fertilizers is critical if sustainable development goal two of zero hunger and agroecosystem resilience are to be achieved for African smallholder agroecosystems. These heterogeneous systems are characterized by poor soil health mainly attributed to soil nutrient depletion. However, conventional methods do not take into account spatial patterns across geographies within agroecosystems, which poses great challenges for targeted interventions of nutrient management. This study aimed to develop a novel population-based farm survey approach for diagnosing soil nutrient deficiencies. The approach embraces principles of land health surveillance of problem definition and rigorous sampling scheme. The advent of rapid soil testing techniques, like infrared spectroscopy, offers opportune avenues for high-density soil and plant characterization. A farm survey was conducted on 64 maize fields, to collect data on soil and plant tissue nutrient concentration and grain yield (GY) for maize crops, using hierarchical and purposive sampling. Correlations between soil test values with GY and biomass were established. The relationship between GY, soil NPK, and the tissue nutrient concentrations was evaluated to guide the setting up of localized critical soil test values. Diagnosis Recommendation Integrated System (DRIS) indices for total nitrogen (N), total phosphorus (P), and total potassium (K) were used to rank and map the prevalence of nutrient limitations. A positive correlation existed between plant tissue nutrient concentration with GY with R2 values of 0.089, 0.033, and 0.001 for NPK, respectively. Soil test cut-off values were 0.01%, 12 mg kg-1, 4.5 cmolc kg-1 for NPK, respectively, which varied slightly from established soil critical values for soil nutrient diagnostics. N and K were the most limiting nutrients for maize production in 67% of sampled fields. The study demonstrates that a population-based farm survey of crop fields can be a useful tool in nutrient diagnostics and setting priorities for site-specific fertilizer recommendations. A larger-scale application of the approach is warranted.