Uptake Of Maize Research Articles

Investigating plasma activated water as a sustainable treatment for improving growth and nutrient uptake in maize and pea plant

In this study, an atmospheric pressure air plasma jet (APAPJ) was employed to generate plasma-activated water (PAW), which was applied to treat maize (monocot) and pea (dicot) seeds for evaluating its influence. This research explored APAPJ diagnostics by varying the air feed rate as 1, 2, and 3 liter per minute (Lpm) through current-voltage characterization, optical emission spectroscopy, electron temperature and density, nitrogen metastable state density, and rotational and vibrational temperature of the plasma. Additionally, various reactive oxygen and nitrogen species (RONS) formed and physicochemical properties of PAW were analyzed by varying plasma treatment time from 0 to 8 min. Furthermore, the water uptake of maize (Zea mays) and pea (Pisum sativum) seeds were examined by the measurement of the contact angle. Results indicated that APAPJ has the capacity of fostering germination, growth, chlorophyll, phosphorus, nitrite, nitrate, ammonium ion and leaf area in plants significantly with an optimized 6 min treated PAW for maize and 2 min treated PAW for peas. Among various categories, seeds soaked in PAW and irrigated with PAW exhibited the most outstanding result in germination and plant growth. Non-thermal plasma showed promising green methods for enhancing plant growth and boosting nutrient content.

Genome-wide transcriptome and gene family analysis reveal candidate genes associated with potassium uptake of maize colonized by arbuscular mycorrhizal fungi

BackgroundPotassium (K) is an essential nutrient for plant growth and development. Maize (Zea mays) is a widely planted crops in the world and requires a huge amount of K fertilizer. Arbuscular mycorrhizal fungi (AMF) are closely related to the K uptake of maize. Genetic improvement of maize K utilization efficiency will require elucidating the molecular mechanisms of maize K uptake through the mycorrhizal pathway. Here, we employed transcriptome and gene family analysis to elucidate the mechanism influencing the K uptake and utilization efficiency of mycorrhizal maize.Methods and resultsThe transcriptomes of maize were studied with and without AMF inoculation and under different K conditions. AM symbiosis increased the K concentration and dry weight of maize plants. RNA sequencing revealed that genes associated with the activity of the apoplast and nutrient reservoir were significantly enriched in mycorrhizal roots under low-K conditions but not under high-K conditions. Weighted gene correlation network analysis revealed that three modules were strongly correlated with K content. Twenty-one hub genes enriched in pathways associated with glycerophospholipid metabolism, glycerolipid metabolism, starch and sucrose metabolism, and anthocyanin biosynthesis were further identified. In general, these hub genes were upregulated in AMF-colonized roots under low-K conditions. Additionally, the members of 14 gene families associated with K obtain were identified (ARF: 38, ILK: 4, RBOH: 12, RUPO: 20, MAPKK: 89, CBL: 14, CIPK: 44, CPK: 40, PIN: 10, MYB: 174, NPF: 79, KT: 19, HAK/HKT/KUP: 38, and CPA: 8) from maize. The transcript levels of these genes showed that 92 genes (ARF:6, CBL:5, CIPK:13, CPK:2, HAK/HKT/KUP:7, PIN:2, MYB:26, NPF:16, RBOH:1, MAPKK:12 and RUPO:2) were upregulated with AM symbiosis under low-K conditions.ConclusionsThis study indicated that AMF increase the resistance of maize to low-K stress by regulating K uptake at the gene transcription level. Our findings provide a genome-level resource for the functional assignment of genes regulated by K treatment and AM symbiosis in K uptake-related gene families in maize. This may contribute to elucidate the molecular mechanisms of maize response to low K stress with AMF inoculation, and provided a theoretical basis for AMF application in the crop field.

The effects of EDTA and Trichoderma species on growth and Cu uptake of maize (Zea mays) plants grown in a Cu-contaminated soil.

Metal contamination in soil poses a significant environmental concern worldwide, necessitating effective remediation strategies such as phytoremediation. The present study investigated the effects of EDTA dosage (1.5 and 3mmolkg-1) and two Trichoderma species (T. harzianum and T. aureoviride) on copper (Cu) content and growth of maize plants grown in a Cu-contaminated soil, as well as Cu fractionation in the soil. In the absence of EDTA, only inoculation with T. harzianum led to a significant increase in shoot biomass. Combining fungal inoculum with EDTA only yielded a significant increase in shoot biomass when using T. aureoviride at a low EDTA rate, highlighting the interplay between fungal species and EDTA rates on plant growth. Results also indicated that EDTA application increased Cu bioavailability, enhancing Cu dissolution and root (not shoot) Cu concentrations. Conversely, inoculation with both Trichoderma species reduced Cu mobility and bioavailability in soil, thereby decreasing the shoot Cu concentrations of plants. When combined with EDTA, only application of T. harzianum resulted in an enhanced shoot Cu concentration, whereas combined application of T. aureoviride and EDTA did not make a significant change compared to the corresponding control (no fungal inoculation, no EDTA), possibly due to a lower compatibility of the T. aureoviride isolate with EDTA. Our results demonstrated that EDTA application, in both non-inoculated and inoculated treatments, increased Cu availability by facilitating its redistribution and transformation from less plant-available fractions (residual, Fe/Mn oxide-bound, and carbonate-bound) to the more readily plant-available forms (water-soluble and exchangeable fractions). In conclusion, although individual Trichoderma application proved beneficial for phytostabilization by reducing Cu content and mitigating Cu toxicity in plants, the combined application of EDTA and a compatible Trichoderma isolate (here, the T. harzianum isolate) holds promise for enhancing the phytoextraction capacity of plants. Although using maize has the advantage of being a food crop, to optimize phytoextraction, plant species with superior metal tolerance and phytoextraction capabilities should be selected, exceeding those of maize.

Nitrogen and zinc supplements can enhance morphology and physiology traits of maize at early growth stages

Several studies emphasized the importance of zinc for better morpho-physiology in plants. The co-application of Zn can reduce N loss by increasing its uptake rates, but whether N level can affect Zn accumulation in different plant organs is not well studied. This experiment aimed to examine the impact of different levels of nitrogen and zinc on the morphology, physiology and nutrient uptake of maize, and whether different N levels would affect Zn accumulation. Two maize genotypes were grown hydroponically. Nitrogen was supplemented in two different concentrations, combined with two Zn concentrations. Zn level did not affect the shoot or the root dry weight of either genotype under optimal N level, but did under reduced N level. Reduced N level resulted in significantly higher root dry weight under both Zn concentrations in both genotypes. Significantly higher nitrogen remobilization rate was found at reduced N level in both genotypes. Optimal N level resulted in higher shoot and root N and Zn contents in both genotypes. The uptake of Zn was enhanced by optimal N compared to reduced N level, where the impact of genotypes was also observable. Reduced N level decreased both optimal and actual photochemical efficiency of photosystem II, and pigment contents of both genotypes. It could be concluded that N and Zn use efficiency is highly dependent on the genetic characteristics of maize genotypes, but optimal N supply is required for better incorporation of Zn into shoot and root tissues.

Soil properties and nutrient uptake of maize (Zea mays) as influenced by mixed manure and blended inorganic fertilizer in Haramaya district, eastern Ethiopia

The deteriorating state of soil fertility and low agricultural productivity in Ethiopia can be traced to the lack of equivalent consideration given to the soil's biological, chemical, and physical properties. A pot experiment was conducted to investigate the effect of mixed manure and blended nitrogen, phosphorus, sulfur and boron (NPSB) fertilizer on phosphorus adsorption, and other properties of Vertisols, nutrient uptake, and growth performance of maize. The study findings indicate that the combined application of mixed manure and blended NPSB significantly reduced soil pH from 7.87 to 7.68, phosphorus adsorption efficiency from 93 to 88.5 %, and Freundlich adsorption capacity from 194 to 100.75 mg kg−1 , intensity from 1.96 to 1.27 compared to control. However, combined application of these two treatments significantly increased the organic carbon from 0.81 to 1.64 %, total nitrogen from 0.04 to 0.13 %, and available phosphorus from 6.96 to 73.82 g kg−1. The study further revealed that mixed manure and blended NPSB resulted in significantly (p ≤ 0.05) higher contents of nitrogen and phosphorus in the maize leaves as well as their uptake compared to their sole application and control. The highest values of these parameters were observed in plots treated with a combined application of 15 t ha−1 mixed manure with each rate of 100 and 150 kg ha−1 blended NPSB. Additionally, the maize plant height (p ≤ 0.05) and above-ground biomass (p ≤ 0.01) also exhibited significant increase. Compared to the control and full dose of NPSB, all the treatments that received a combined application of 15 t ha−1 mixed manure with blended NPSB ranging from 50 to 150 kg ha−1 resulted in significantly higher above-ground biomass of maize. The results suggest that the combined use of mixed manure and blended NPSB could be a practical and effective approach to improve soil properties and maize above-ground biomass yield.

Influence of modified natural farming application on nutrient content and uptake of maize under maize + cowpea intercropping system

Influence of modified natural farming application on nutrient content and uptake of maize under maize + cowpea intercropping system

Arbuscular Mycorrhizal Fungal Interacted with Biochar and Enhanced Phosphate-Solubilizing Microorganism Abundance and Phosphorus Uptake in Maize

In agricultural production, it is crucial to increase the availability of phosphorus (P) in cultivated soil to solve the P limitation. Arbuscular mycorrhizal fungi (AMF) have been proven to promote crop nutrient absorption effectively, while biochar can lead to improvements in soil properties. However, the possible synergistic effect of AMF and biochar on P uptake by crops as well as its underlying mechanisms are unclear. In this study, we conducted a pot experiment to explore the effects of biochar and AMF (Glomus etunicatum) on the community of rhizospheric phosphate-solubilizing microorganisms (PSMs) of maize (Zea mays L. Xianyu-335) using metagenomic methods. The experiment used 0 mg P2O5 g·kg−1 soil (P0) and 30 mg P2O5 g·kg−1 soil (P30) application rates. Each P application rate included 0 (NC), 20 g·kg−1 biochar (BC) addition, inoculation AMF, and without AMF treatments (NM) for a total of eight treatments. During the experiment, both the P uptake and the biomass of maize were measured. The study found that the combination of AMF and biochar significantly increased the mycorrhizal colonization rate of maize roots, regardless of P application level. It was observed that the P uptake by maize was significantly increased when exposed to a combination of AMF and biochar. The increase in P uptake in P0 treatments was 67% higher than the sum of the effects of biochar and AMF inoculation alone. The increase was only 35% higher in P30 treatments, demonstrating a substantially higher interactive effect under P0 than under P30 conditions. The AM-BC treatments significantly increased the abundance of Streptomyces, Bacillus, and Pseudomonas, genera that are known to contain PSMs. In addition, the abundance of genes related to P-cycling (gcd, phoD, and ugpQ) in PSMs increased significantly by 1.5–1.8 times in AM-BC treatments compared with NM-BC and AM-NC treatments under P0 conditions. This increase was significantly and positively correlated with the P uptake. Overall, the results suggest that biochar can help AMF colonize the roots, increasing the functional roles of PSMs in the rhizosphere, which in turn promotes P uptake and biomass in maize. This study provides a new way to improve P-use efficiency and reduce the need for P-fertilizer application in agricultural production.

Effects of phosphate fertilization and sulfadiazine on plant growth, root morphology, nitrogen and phosphorus uptake of soybean and maize

Low soil phosphorus (P) availability is a limiting factor for crop production. Application of livestock manure as organic fertilizer can increase soil P availability, but may cause soil contamination with antibiotics such as sulfadiazine (SD), thus adversely affecting plant growth and nutrient uptake. The effects of P (0 and 50 mg kg−1) and SD (0, 1, 10, and 100 mg kg−1) levels on plant growth, root development, and nitrogen (N) and P uptake of maize and soybean were examined in a pot experiment using a loess soil as the test soil. High levels of SD considerably inhibited plant growth of both crops. Both P fertilization and SD negatively affected root development of both crops, especially at higher SD levels. For both crops, the average root diameter and the proportion of thick roots increased with increasing soil SD level. When soil SD level was ≤10 mg kg−1, the effects of P fertilization and SD on plant N and P concentrations, and N:P, N- and P-utilization efficiency were not significant in most cases. The effects of SD on plant N and P nutrition could not be of a great concern when soil SD level was ≤10 mg kg−1. Overall, soil SD pollution could reduce plant biomass and inhibit root development of soybean and maize, with a stronger effect on root development than on plant biomass at a high soil SD level (≥10 mg kg−1). In agricultural production, attention should be paid to soil SD pollution via manure application.

Maize zinc uptake is influenced by arbuscular mycorrhizal symbiosis under various soil phosphorus availabilities.

The antagonistic interplay between phosphorus (P) and zinc (Zn) in plants is well established. However, the molecular mechanisms mediating those interactions as influenced by arbuscular mycorrhizal (AM) symbiosis remain unclear. We investigated Zn concentrations, root AM symbiosis, and transcriptome profiles of maize roots grown under field conditions upon different P levels. We also validated genotype-dependent P-Zn uptake in selected genotypes from a MAGIC population and conducted mycorrhizal inoculation experiments using mycorrhizal-defective mutant pht1;6 to elucidate the significance of AM symbiosis in P-Zn antagonism. Finally, we assessed how P supply affects Zn transporters and Zn uptake in extraradical hyphae within a three-compartment system. Elevated P levels led to a significant reduction in maize Zn concentration across the population, correlating with a marked decline in AM symbiosis, thus elucidating the P-Zn antagonism. We also identified ZmPht1;6 is crucial for AM symbiosis and confirmed that P-Zn antagonistic uptake is dependent on AM symbiosis. Moreover, we found that high P suppressed the expression of the fungal RiZRT1 and RiZnT1 genes, potentially impacting hyphal Zn uptake. We conclude that high P exerts systemic regulation over root and AM hyphae-mediated Zn uptake in maize. These findings hold implications for breeding Zn deficiency-tolerant maize varieties.

Influence of applied as well as residual phosphorus and defoliant on yield and nutrient uptake of maize under pigeonpea-maize cropping system

Influence of applied as well as residual phosphorus and defoliant on yield and nutrient uptake of maize under pigeonpea-maize cropping system

Identifying a new "nitrate master": ZmEREB97 regulates nitrate uptake in maize.

Identifying a new "nitrate master": ZmEREB97 regulates nitrate uptake in maize.

Transcription factor ZmEREB97 regulates nitrate uptake in maize (Zea mays) roots.

Maize (Zea mays L.) has very strong requirements for nitrogen. However, the molecular mechanisms underlying the regulations of nitrogen uptake and translocation in this species are not fully understood. Here, we report that an APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factor ZmEREB97 functions as an important regulator in the N signaling network in maize. Predominantly expressed and accumulated in main root and lateral root primordia, ZmEREB97 rapidly responded to nitrate treatment. By overlapping the analyses of differentially expressed genes and conducting a DAP-seq assay, we identified 1,446 potential target genes of ZmEREB97. Among these, 764 genes were coregulated in 2 lines of zmereb97 mutants. Loss of function of ZmEREB97 substantially weakened plant growth under both hydroponic and soil conditions. Physiological characterization of zmereb97 mutant plants demonstrated that reduced biomass and grain yield were both associated with reduced nitrate influx, decreased nitrate content, and less N accumulation. We further demonstrated that ZmEREB97 directly targets and regulates the expression of 6 ZmNRT genes by binding to the GCC-box-related sequences in gene promoters. Collectively, these data suggest that ZmEREB97 is a major positive regulator of the nitrate response and that it plays an important role in optimizing nitrate uptake, offering a target for improvement of nitrogen use efficiency in crops.

Growth and cadmium and nickel uptake of maize (Zea mays L.) in a cadmium and nickel co‑contaminated soil and phytoremediation efficiency using ethylenediamine tetraacetic acid

Background: Anthropogenic activities release cadmium (Cd), nickel (Ni), and other heavy metals into soil. Zea mays can clean up contaminated soils, but little is known about how Cd and Ni co-contamination stress affects ethylenediamine tetraacetic acid (EDTA)-based phytoextraction and phytoremediation, hence this study was conducted. Methods: The experiment involved nine treatment levels (0, 5, 10, 15, and 20 mg kg-1 Cd and 0, 15, 30, 45, and 60 mg kg-1 Ni), grouped into three categories: CT as the control group, P as Cd + Ni only, and CAP as Cd + Ni + EDTA (n=3). The treatments used (CH3COO)2Cd•2H2O and NiSO4 as the source of Cd and Ni, respectively, and EDTA was applied at two rates (0 and 0.5 g/kg). After the experimental period, measurements were taken for shoot length, biomass, and metal concentrations in both the roots and shoots using established procedures. Results: The concentrations of metals in plants' roots and shoots increased as the concentrations in soil increased, but shoot length, biomass, bioconcentration factor (BCF), and translocation factor (TF) values decreased with increasing soil metal content. The application of EDTA increased metal uptake but led to greater root and shoot biomass loss. Generally, TF values for Cd and Ni were less than 1 but most of the BCF values were greater than 1. Conclusions: The study found that phytostabilization is the main mechanism for phytoremediation of Cd-Ni-co-contaminated soils with Zea mays, with EDTA addition enhancing metal accumulation and reducing biomass yield.

Response of Maize (Zea mays L.) to Nitrogen Levels, Conventional and Enriched Organic Manures on Yield and Major Nutrient Uptake in a Vertisol

A field experiment was conducted during kharif 2015-16 at Mulmuthla village of Dharwad taluk in Dharwad district, Karnataka, India. Research conducted to study the effect of enriched FYM and vermicompost and nitrogen levels on yield and majornutrient uptake of maize (Zea mays L.) in a Vertisol. The split plot design with four replication and twelve treatment combinations. Application of nitrogen at 200 kg ha-1+ Zn+Fe enriched vermicompost at 2.5 t ha-1 was found superior in terms of grain yield (79.93 q ha-1), stover yield (88.77 q ha-1) and test weight (100 seeds) (39.67 g) over other treatments. Similarly, the highest NPK uptake (232.33, 48.73 and 175.59 kg ha-1) was recorded with the application of 200 kg N + Zn+Fe enriched vermicompost at 2.5 t ha-1. So the study of effect of different combinations of nutrients like nitrogen, enriched FYM, FYM, enriched vermicompost, vermicompost and their interactions over yielding ability of maize can help in developing a best source of nutrients for maize yield and uptake.

Nutrient Uptake of Maize as Influenced by Intercropping with Different Genotype of Groundnut under Temperate Kashmir Valley

A field experiment on ‘Nutrient uptake of maize as influenced by intercropping with different genotype of groundnut under temperate Kashmir valley” was conducted at Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Wadura, Sopore during 2021 and 2022. The experimental soil exhibited silty clay loam characteristics with adequate drainage and normal levels of both reaction and salinity. The experimental treatments comprised of sole crops and various row proportions of maize intercropped with groundnut. The experimental design was randomized complete block design, consist nineteen treatments that were replicated three times. Treatment comprised of T1 (Sole maize, 60 cm), T2 (sole paired maize, 75-45-75 cm), T3 (Sole paired maize,90-30-90 cm), T4 (Sole groundnut TG-84), T5 (Sole groundnut TG-37-A), T6 (Sole groundnut TG-88), T7 (Sole groundnut TG-89), T8 Alternate row of maize + groundnut TG- 84 (30 + 30 cm ),T9 Paired row of maize + groundnut TG- 84 (75-45-75 cm maize in between 25-25 cm groundnut),T10 Paired row of maize + groundnut TG- 84 (90-30-90 cm maize in between 30-30 cm groundnut), T11 Alternate row of maize + groundnut TG- 37-A (30 + 30 cm ) T12 Paired row of maize + groundnut TG- 37-A (75-45-75 cm maize in between 25-25 cm groundnut), T13 paired row of maize + Groundnut TG- 37-A (90-30-90 cm maize in between 30-30 cm groundnut), T14 Alternate rows of maize + Groundnut TG- 88 (30 + 30 cm),T15 Paired row of maize + groundnut TG- 88 (75-45-75 cm maize in between 25-25 cm groundnut), T16 Paired row of maize + groundnut TG- 88 (90-30-90 cm maize in between 30-30 cm groundnut), T17 Alternate rows of maize + groundnut TG- 89 (30 + 30 cm), T18 Paired row of maize + groundnut TG- 89 (75-45-75 cm maize in between 25-25 cm groundnut), T19 Paired row of maize+ groundnut TG- 89 (90-30-90 cm maize in between 30-30 cm groundnut). The two years of result revealed that intercropping increased the total N, P and K uptake and enhancing yield of both the crop. Total N, P and K uptake was recorded significantly higher with paired row of maize (75/45 cm spacing) in intercrop with groundnut variety TG-37-A as compared to sole maize. In intercrop N, P and K uptake was recorded significantly higher in sole groundnut variety TG-37-A followed by TG-84, TG-88 and TG-89.

Pengaruh Pemberian Berbagai Macam Bahan Organik terhadap Ketersediaan Hara Nitrogen, Fosfor dan Kalium serta Serapan Nitrogen oleh Jagung (Zea mays L.) pada Tanah Ultisols

Ultisols distributes spreadly in Indonesia, but this soil has low fertility. Therefore, the application of organic matter (OM) is a common management to increase this soil fertility. The purpose of this study was to determine the role of different types of OM (originated from animals and plants) on the availability of nitrogen, phosphorus, and potassium as well as nitrogen uptake in maize in Ultisols. Soil with a mass of 5 kg without organic matter (control), with the application of chicken manure, cow manure, swallow manure, kirinyuh, babadotan, and kalopo manure were incubated in experimental pots for two weeks at 60% field capacity. After the completion of the incubation period, soil sub-sampling was carried out for the determination of available N, available P and exchangeable K. Furthermore, in each experimental pot, corn seeds were planted, and the observations of dried-weight of corn and nitrogen uptake in corn were observed in a vegetative phase. The results showed that the application of different types of organic matter increased soil pH, nitrate content, exchangeable K, plant dried-weight and plant nitrogen uptake. The content of ammonium and available P was not affected by OM addition. The results also showed that OM derived from animals resulted in higher increases in pH and exchangeable K than those derived from plants. However, OM derived from plants resulted in higher increases in nitrate, plant dry weight and better plant N uptake than OM from animal waste. The results of this study show that the application of OM results in increases in some soil chemical properties, in which the degree of increases in soil chemical characteristics is controlled by the OM origin.

Water use characteristics of an early and late maturing maize hybrid using stable isotopes

AbstractWater requirements of early‐maturing (EM) maize hybrids might be lower than those of late‐maturing (LM) maize hybrids. This study aimed to analyze the effects of different irrigation management on grain yield (GY), water uptake patterns, evaporation (E), and transpiration (T) of two maize hybrids differing in maturity via stable isotope method. The field experiment with 36 lysimeters (4‐m wide × 4‐m long) under rain‐shelters was conducted with an EM (DH518) and a mid‐maturing and LM (DH605) hybrid with three replicates from 2021 to 2022. Maize plants were grown under three irrigation amounts (W1, W2, and W3 were irrigated to maintain soil moisture at 45%, 60%, and 75% of field capacity, respectively) by flood irrigation (FI) and drip irrigation (DI) under rain‐out shelters. Results showed that GY and evapotranspiration (ET) of EM were 8% and 12% lower, while the crop water productivity (CWP) was 6% higher than that of LM. Water uptake of both hybrids occurred mainly within 0‐ to 60‐cm soil layer during the vegetative stage. Water uptake of both hybrids occurred mainly within 0‐ to 60‐cm soil layer during the vegetative stage. Summer maize under FI absorbed more water from the deep soil layer than DI in the late growth stage. Compared with LM, the water absorption depth of EM became shallower in the late growth stage. Water uptake of maize was mainly from the deeper soil under water stress conditions. E of total ET accounts for 43% under DI and 57% under FI; GY and CWP were 22% and 51% higher than those of FI. Together with choosing EM hybrids, optimization of water management with DIW3 could achieve higher GY and CWP. The optimization of irrigation method and hybrids could provide a reference for local farmers to improve GY and CWP.

Impact of Long-Term Organic Manure Application on Yield, Zinc, and Copper Uptake in Maize, Peas, and Mungbean (Vigna radiata L.) Cropping System

To evaluate the impact of the long-term application of organic manures on yield, uptake of zinc and copper in maize, peas and summer mungbean cropping systems, a field study was conducted at the integrated farming system of Punjab Agricultural University, Ludhiana. The treatment combinations were; T1: 50% N through recommended NPK + 50% N was substituted through FYM, T2: 100% N through FYM, T3: T2 + intercropping (marigold in pea, cowpea in maize), T4: T2 + agronomic practices for weed and. pest control, T5: 50% N as FYM + rock phosphate to substitute the P requirement of crops + phosphate solubilizing bacterial. cultures (PSB), T6: T2 + biofertilizer (consortium) containing N and P carriers and T7: 100% Recommended NPK through chemical fertilizers. Significant increases in the yield, micronutrient content and uptake were recorded due to the application of 50% nitrogen through farmyard manure (FYM) and 50% of the recommended dose of fertilizers (T1) followed by 100% N through FYM + biofertilizer containing. N and P, carriers (T6). The highest grain yield of maize (5.72 t ha-1), pea (16.2 t ha-1) and summer mungbean (11.6 t ha-1) were recorded in treatment T1, surpassing the 100% recommended dose of fertilizer (T7) by 13.7%, 20% and 10.4 %, respectively. The concentration of copper (Cu) and zinc (Zn) in the grains of maize, pea and summer mung bean was 38.3%, 14.1%, 29.6% and 53.4%, 22.8 % and 19.8% higher in treatment T1 as compared to treatment T7. Moreover, the concentration of copper and zinc in the grains of maize, pea and summer mung bean was 32.1%, 24.2% and 29.5 % and 21.7%, 17.6% and 11.6% higher in treatment T1, respectively, compared to treatment T7. Similarly, the increase in the uptake of Cu and Zn was observed in both grain and straw of maize, pea and summer mung bean. The study concluded that the integrated nutrient management (INM) treatment is to substitute a portion of chemical fertilizers with a more sustainable and environmentally safe organic compost in order to mitigate soil degradation, improve crop production, and protect the environment.

Coupling phosphate type and placement promotes maize growth and phosphorus uptake by altering root properties and rhizosphere processes

ContextNutrient distribution and phosphate fertilizers can impact maize growth, but how to match the type of phosphate fertilizer and the application method to enhance root-foraging capacity for phosphorus (P) is unclear. ObjectiveThis study was aimed at characterizing the effects of different phosphate fertilizers and placements on maize growth, grain yield, root properties and rhizosphere processes on calcareous soil. MethodsA soil column experiment with five different phosphate fertilizers [single superphosphate (SSP), monoammonium phosphate (MAP), diammonium phosphate (DAP), urea phosphate (UP) and ammonium polyphosphate (APP)] applied either uniformly or locally 10–20 cm deep in a greenhouse. In addition, a 2-year field experiment with five P fertilizer treatments (non-fertilization and broadcast MAP, DAP, UP or APP) was conducted. ResultsIn the soil column experiment, localized application of SSP, MAP, UP and APP significantly promoted the growth and P uptake of maize by modifying the root morphology. Localized application of each P fertilizer increased (by up to 74 %) the first-order lateral root density and first-order lateral root length of maize in the fertilizer-enriched layer, resulting in a significant increase in the efficiency of root P acquisition by maize. In the field experiment, the rhizosphere pH of maize supplied with MAP, UP or APP was reduced by 0.5–0.7 units in comparison to DAP in 2018. Compared with MAP and DAP, application of UP or APP in the field did not show significantly improve maize growth and P uptake. ConclusionsThese results show that optimizing P fertilizer types and placement modified root morphology and physiology, and consequently promoted maize growth and P accumulation, but further characterization of the localized application of different P fertilizers in the field is needed. SignificanceEngineering root properties and rhizosphere processes by manipulating fertilizer types and placement improves fertilizer-use efficiency and reduces environmental footprint of food production.

Applicability of the sigmoid model to estimate heavy metal uptake in maize and sorghum as affected by organic acids.

Although assisted phytoremediation using chemical treatments is a suitable technique for the removal of heavy metals (HMs), the estimation of this process using simple models is also crucial. For this purpose, a greenhouse trial was designed to evaluate the effectiveness of citric, oxalic, and tartaric acid on Cd, Pb, Ni, and Zn phytoremediation by maize and sorghum and to estimate this process using sigmoid HMs uptake model. Results showed that mean values of root and shoot dry weight and metals uptake, translocation factor (TF) of Pb and Zn, and uptake efficiency (UE) of Cd in maize were higher than sorghum but the TF of Cd and the phytoextraction efficiency (PEE) and UE of Pb in sorghum were higher than maize. Citric, oxalic, and tartaric acid significantly increased the UE of Pb by 17.7%, 22.5%, and 32.5%, respectively. Tartaric acid significantly increased the mean values of shoot dry weight, shoot Cd, Pb, and Ni uptake, and PEE of Pb and Ni, but decreased TF of Zn. The R2, NRMSE, and KM values indicated the ability of sigmoid HM uptake model in estimating HMs uptake in maize and sorghum treated with organic acids. Thus, tartaric acid was more effective than citric and oxalic acids to enhance phytoremediation potential. Sigmoid HM uptake model is suitable to estimate the HMs uptake in plants treated with organic acids at different growth stages.