Maize Grain Research Articles

Higher lime rates for greater nitrogen recovery: A long-term no-till experiment labeled with 15N

Soil acidity limits crop growth and yield all over the world. Low grain yields is usually associated with poor soil fertility; however, little attention has been given to the nitrogen-based fertilizer use efficiency in soils managed with lime. Given the current scenario of uncertainties regarding the availability and prices of fertilizers, our study aimed to understand how maize intercropped with ruzigrass and soybean plants develop in long-term soils managed with lime rates, and what the fate of the 15N–labeled ammonium sulfate [(15NH4)2SO4] applied in the soil-plant system. The treatments consisted of four dolomitic lime rates applied to the soil surface [control, half the recommended lime rate (½ RLR), full recommended lime rate (1 RLR) and double the recommended lime rate (2 RLR)]. The higher lime rate (2 RLR) improved fertility, carbon and nitrogen stocks in the soil profile, and grain and/or stover production of maize, ruzigrass and soybean. As a consequence, maize and ruzigrass recovered a high amount of 15N-fertilizer. On the other hand, soybean recovered less 15N-fertilizer, regardless of treatment, but a greater amount was found in acidic soils. At the end of the maize and soybean growth cycles, our results showed that in 2 RLR-amended soil, the 15N unrecovered was 71% lower than control. Finally, our results suggested that the use of low lime rates (½ RLR) may increase the 15N losses potential to deep layers, whereas low amounts of 15N were found in the subsoil when higher lime rates were applied. Soil acidity management through higher lime rates leads, over time, to increased soil fertility, resulting in a favorable environment for plant growth and the use of nitrogen fertilizers. In this way, it is possible to obtain a more productive and less costly agricultural system, and with less potential to pollute the environment.

Simulation of Maize Phenology and Grain Yield Using DSSAT Model

The field experiment was conducted at the Farm of College of Agricultural Engineering and Technology, Godhra, Gujarat during the year 2018-19 and 2019-20 to simulate the phenology and yield of rabi maize (Zea mays L.) in sandy loam soil of the central Gujarat. The field experiment design was split split plot with 36 treatment combinations with 3 replications including three irrigation regimes (1.0IW/CPE, 0.8IW/CPE and 0.6IW/CPE), four mulch conditions (control, paddy straw, black plastic, and reflective silver plastic mulch), and three stages (tasselling, silking and dough stage). The experimental data of the year 2018-19 and 2019-20 was used for the calibration and validation of the model respectively. The result revealed a significant difference in grain yield due to irrigation regime, mulching and growth stages. The DSSAT model could good simulate grain yield (R2 = 0.989) under the simulation of irrigation regimes, mulching, and growth stages.

Amaranth yield depending on the sowing rate

The main value of amaranth lies in its ability to accumulate a large amount of protein in its seeds and leaves. With a seed protein content of 15-18%, amaranth surpasses wheat (12-14%), rice (7-10%), maize (9-10%), and other grain crops. The purpose of this study was to establish the optimal seed sowing rates for amaranth under the conditions of the Western Ukrainian Forest-Steppe zone. The study employed general scientific methods such as analysis, synthesis, experimentation, description, observation, and comparison, as well as field methods like phenological observations and record-keeping, along with statistical and correlation-regression analyses for data processing. The sowing rates of the variety Kharkivskyi 1 were investigated under conditions of sufficient moisture on dark-grey forest soil. It was found that the field germination varied with different sowing rates. At a sowing rate of 0.2 million seeds/ha, the field uniformity was 70%, but it decreased to 60% at a sowing rate of 1.2 million seeds/ha, representing a 10% decrease. Higher sowing rates resulted in greater plant density. In the seedling stage, there were 14 plants per 0.2 million seeds/ha sowing rate, while at 1.2 million seeds/ha, the number of plants increased to 72/m². Plant survival during the vegetation period sharply decreased with increased planting density, from 86% at a sowing rate of 0.2 million seeds/ha to 45% at a sowing rate of 1.2 million seeds/ha. Therefore, before harvesting, the plant density was adjusted to 12-32 plants/m². The best combination of the main elements of the structure was found to be 21 plants/m² and 26 plants/m², with a grain weight per plant of 20.4g and 16.1g, respectively. The highest grain yield of amaranth variety Kharkivskyi 1 was obtained at sowing rates of 0.4 million seeds/ha and 0.6 million seeds/ha, resulting in 4.28 t/ha and 4.20 t/ha, respectively. Any increase or decrease in sowing rates led to a decrease in the yield level. The results of this study can be used for further establishment and improvement of the main elements of amaranth cultivation technology by both scientific institutions and agricultural farms

The Effect of Ustilago maydis and Delayed Harvesting on A- and B-Type Trichothecene Concentrations in Maize Grain.

The aim of this study was to investigate whether, in the context of a higher incidence of Ustilago maydis and Fusarium spp. at optimal and delayed harvest times, a higher incidence of mycotoxin contamination in maize grains could be expected. The field experiment was carried out at the Lithuanian Research Centre for Agriculture and Forestry experimental fields over three consecutive years (2020-2022). Two maize hybrids (Duxxbury and Lapriora) with different FAO numbers were used. The experimental design in the field was a randomized complete block design. Harvesting took place at three different times: first at physiological maturity, and then 10 (±2) and 20 (±2) days after the first harvest. Each hybrid had four repetitions at different harvest times. The U. maydis infection was only detected in 2021 and after the first harvest cobs were further divided into four different groups with four repetitions: healthy cobs, cobs visually infected with Fusarium spp., cobs visually infected with common smut, and cobs visually infected with both pathogens. No U. maydis-damaged maize cobs were found in 2020 and 2022. The levels of Fusarium microscopic fungi in maize grains were also from 4 to 16 times higher in 2021 than in 2020 and 2022. Harvest delays in 2020 led to a significant deoxynivalenol concentration increase in the Duxxbury hybrid and an HT-2 concentration increase in the Lapriora hybrid. In 2021, deoxynivalenol, 3-acetyl-deoxynivalenol, 15-acetyl-deoxynivalenol, and HT-2 concentrations significantly rose in both hybrids, but the T-2 concentration significantly increased only in the Lapriora hybrid. Deoxynivalenol concentrations were, respectively, 110 and 14.6 times higher than in cobs only infected with Fusarium spp. or U. maydis. Concentrations of 15-acetyl-deoxynivalenol were, respectively, 60, 67, and 43 times higher than in asymptomatic cobs and cobs only infected with Fusarium spp. or U. maydis. Cobs contaminated with both pathogens also had higher concentrations of 3-acetyl-deoxynivalenol. T-2 and HT-2 were detected in maize grains harvested from cobs infected only with Fusarium spp. The presence of U. maydis and Fusarium fungi in maize cobs, along with harvest delays, led to significant increases in mycotoxin concentrations, highlighting the importance of timely harvesting and pathogen management to mitigate mycotoxin contamination in maize grains.

Uncovering the potentials of long-term straw return and nitrogen supply on subtropical maize (Zea mays L.) photosynthesis and grain yield

ContextCrop straw is a significant byproduct of agricultural production and a rich source of nutrients, but it is carelessly disposed of, potentially harming the environment and wasting valuable resources. In China, returning straw to the soil as a means of disposing of agricultural waste is a crucial management technique that not only makes use of agricultural waste but also enhances soil quality and grain yield. ObjectiveA five-year (2018–2022) field experiment was designed to study the effect of straw treatment methods and optimal nitrogen (N) application rate on the photosynthesis process and grain yield of maize. MethodsThe different straw methods (straw return (SR) and traditional practice (TP) — no straw return) were assigned to main plots while the N levels such as N100 (100 kg ha−1), N150 (150 kg ha−1), N200 (200 kg ha−1), N250 (250 kg ha−1), and N300 (300 kg ha−1) were allotted to sub-plots. ResultsThe results showed the photosynthesis rate (Pn), intercellular carbon dioxide concentration, stomatal conductance, transpiration rate, relative chlorophyll content (SPAD), leaf area index (LAI), dry matter (DM), soil nitrogen content, maize grain nitrogen accumulation, and grain yield were increased with an increase in N levels. Similarly, SR also showed a promotion effect on the aforementioned parameters compared with TP. After five years, SR with an optimum N level (250 kg ha−1) increased the SPAD values (2%) and Pn (8%) which resulted in higher LAI (27%) compared with TPN300. As a result, more DM (15%) was formed and finally increased the grain yield (7%). It was revealed that the SPAD, Pn, LAI, DM, and grain yield were maximum at a higher 300 kg N ha−1 level but it was found statistically similar with 250 kg N ha−1. So in this study, SR with 250 kg N ha−1 is optimum for better photosynthetic efficiency, dry matter production, and grain yield. The correlation analysis also showed a positive correlation (i) of SPAD values with Pn (ii) LAI with SPAD values and Pn, (iii) DM with SPAD values, Pn, and LAI, and (iv) grain yield with DM under SR compared with TP. Conclusion and implicationIn summary, SRN250 resulted in better chlorophyll content and photosynthesis process that yielded more photosynthetic area for higher DM production and subsequently higher maize grain yield. The SR reduced the amount of N fertilizer and improved the grain yield and it is the best approach to improve grain yield and minimize agricultural waste production. Long-term trials are needed to understand the effects of straw incorporation and nitrogen application in different regions and locations.

Combining field data and modeling to better understand maize growth response to phosphorus (P) fertilizer application and soil P dynamics in calcareous soils

We used field experimental data to evaluate the ability of the agricultural production system model (APSIM) to simulate soil P availability, maize biomass and grain yield in response to P fertilizer applications on a fluvo-aquic soil in the North China Plain. Crop and soil data from a 2-year experiment with three P fertilizer application rates (0, 75 and 300 kg P2O5 ha−1) were used to calibrate the model. Sensitivity analysis was carried out to investigate the influence of APSIM SoilP parameters on the simulated P availability in soil and maize growth. Crop and soil P parameters were then derived by matching or relating the simulation results to observed crop biomass, yield, P uptake and Olsen-P in soil. The re-parameterized model was further validated against 2 years of independent data at the same sites. The re-parameterized model enabled good simulation of the maize leaf area index (LAI), biomass, grain yield, P uptake, and grain P content in response to different levels of P additions against both the calibration and validation datasets. Our results showed that APSIM needs to be re-parameterized for simulation of maize LAI dynamics through modification of leaf size curve and a reduction in the rate of leaf senescence for modern stay-green maize cultivars in China. The P concentration limits (maximum and minimum P concentrations in organs) at different stages also need to be adjusted. Our results further showed a curvilinear relationship between the measured Olsen-P concentration and simulated labile P content, which could facilitate the initialization of APSIM P pools in the NCP with Olsen-P measurements in future studies. It remains difficult to parameterize the APSIM SoilP module due to the conceptual nature of the pools and simplified conceptualization of key P transformation processes. A fundamental understanding still needs to be developed for modelling and predicting the fate of applied P fertilizers in soils with contrasting physical and chemical characteristics.

Spineless cactus cladode is a viable replacement to barley and maize grains in the feed rations of dromedary camel calves.

No studies determined the use of spineless cactus cladodes in camel diets. The effect of replacing the main energy source in camel diets with fresh spineless cactus cladodes on growth performance was determined. Furthermore, the ability of morphology to predict cladodes yield was determined. A prediction model of spineless cactus cladode weight based on cladode volume was developed. Three cladodes per plants were randomly selected from 100 plants. Weight and volume were then recorded for each cladode. Sixteen male camel calves (196±18.2kg live weight and 430±5.55 days of age) were allotted to treatments, control (conventional camel fattening diet based on cotton seed hulls, cereal grains and agro-industrial by-products) or cactus (barley and maize grains in the control diet were replaced totally by fresh cactus cladode on dry matter basis). The study contained a 100-days growth trial and a 21-day digestibility trial (15 days of adaptation and 7 days of faeces collection). Blood samples were collected monthly from each animal. Cactus cladode volume predicted the dry weight with a high accuracy (prediction error=3.5%). Nutrient intake and nutrient digestibility did not significantly differ among the dietary treatments (p>0.05). The treatment significantly decreased feed conversion ratio by 1.52 points (p<0.05). All blood parameters were within the normal range of dromedary camels. Spineless cactus cladode is a potential replacement to the conventional energy sources in dromedary camel diets.

Zein patterns as effective markers of valuable agronomic traits in maize

The effective use of maize (Zea mays L.) in agriculture depends entirely on the knowledge of its gene pool, which, in turn, needs to undergo registration and certification as new data become available. Maize is one of the model objects for applying the marker methodology. This article summarizes the results of a long-term study of the maize gene pool at N. I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR) in two main areas: identification of the world genetic diversity of maize (including the most important wild relatives for breeding use), and search for reliable protein (zein) markers of traits valuable for breeding in order to use them in improvement, seed production, and seed control of this crop. Specific examples show the effectiveness of using zein markers in the development of new inbred lines and improvement of the existing ones. On the examples of such agronomic traits as early maturity, explosiveness, and waxiness of maize grain, the possibility of controlling the “inclusion” of these traits in the breeding material with the help of zein markers has been demonstrated. Evidence of the effectiveness of applying zein markers in the selection of parental pairs to obtain highly heterotic hybrids is presented. The nomenclature of zein adopted at VIR after its separation by polyacrylamide gel electrophoresis (PAGE) in an acidic buffer was compared with the nomenclature of zein after polyacrylamide gel electrophoresis with sodium dodecyl sulfate (SDS-PAGE) adopted among the foreign scientific community. The studies were performed on a large volume of accessions from the VIR collection as well as on breeding material provided by the country’s leading breeders.

Production and Quality Evaluation of Gluten Free Biscuits from Maize and Soybean Flour Blends

The study evaluated the quality of gluten–free biscuits made from maize and soybean flour blends, and compared them with 100% wheat flour biscuit. Flours were prepared from maize and soybean grains. The soybean flour was used to substitute 5, 10, 15, 20 and 30% of maize flour in order to obtain various flour blends. The chemical composition, functional and pasting properties of the flours and their blends were determined. The flour blends were used to prepare biscuits, which were analyzed for the chemical composition, physical and sensory properties. The results showed that the moisture, protein, fat, fiber, ash, and carbohydrate contents of the flours ranged from 10.58-11.37, 7.30-42.23, 1.82-10.15, 0.34-5.20, 0.85-4.00, 27.84-76.41%, respectively. The phosphorus, iron and magnesium contents varied from 1.24-166.96, 2.31-19.54, 0.01-157.56mg/100g, respectively. The bulk density, foaming capacity, water absorption and oil absorption capacity of the flours and the blends ranged from 0.66-0.68g/cm3, 3.22-29.25%, 85.00-210.00g/g and 80.0-145g/g, respectively. The peak viscosity, trough viscosity, breakdown viscosity, final viscosity, setback viscosity, peak time and pasting temperature decreased with an increase in the level of soybean flour incorporation and ranged from 113.05-127.98, 83.95.97.05, 23.99-41.95, 224.02-409.98, 136.01-325.03, 6.12-7.05, and 55.4-95.0 RVU, respectively. The moisture, protein, fat, fiber, ash, and carbohydrate of the biscuits increased from 4.10-9.19, 34.94-40.38, 27.24-31.39, 6.88-7.93, 0.53-3.79, and 16.99-23.44%, respectively. The phosphorus, iron, and magnesium contents of the biscuits ranged from 47.01-65.91, 3.37-7.08, 0.0018-0.0047mg/100g, respectively. The sensory scores for the biscuit samples decreased with the level of soybean flour. However, the biscuits containing 10% soybean flour was not significantly (p&gt;0.05) different from the 100% wheat flour biscuits in all the sensory attributes evaluated. Therefore, comparable biscuits with 100% wheat biscuit could be produced from the blend of 90 % maize flour and 10% soybean flour.

Content Patterns of Maize Endogenous Hormones and Grain Yield Influenced by Field Phosphorus Application

The content of plant endogenous hormones could be influenced by fertilization, which play an important regulatory role in plant growth and yield formation. However, the effects of phosphate (P) application rates on the dynamical changes in the exogenous hormone content in maize plants to support high-yield production are still unclear. An experiment with six P application rates was designed (P1, 0 kg ha−1; P2, 20 kg ha−1; P3, 40 kg ha−1; P4, 60 kg ha−1; P5, 80 kg ha−1; and P6, 100 kg ha−1), aimed at determining the distribution or biosynthesis of phytohormones in maize roots and leaves, and clarifying the role of P fertilization in the formation of phytohormones. The results showed that P fertilization significantly increased the content of IAA, by 51.57%, and significantly decreased the contents of ABA and GA3, by 18.92% and 19.13% on average compared to P1. The highest increase in IAA was 99.02%, and the highest decreases in ABA and GA3 were 32.30% and 26.85%, respectively, in the P6 treatment in maize roots. Meanwhile, an increase in the IAA (41.34%), SA (27.58%), and GA3 (37.36%) contents and a decrease in the ABA (19.18%) content in maize leaves were observed. The highest increases in IAA, GA3, and SA in the P6 treatment in maize leaves were 57.5%, 62.50%, and 48.57%, respectively, and the highest decrease in ABA was 28.05%. Meanwhile, different contents of endogenous hormones in maize roots and leaves were observed at various maize growth stages. The maize phenotypes and soil available P content were increased with P application as well. A Pearson’s correlation analysis showed that endogenous hormones were significantly correlated with maize phenotypes and yield. Our results confirmed that P fertilization could change the content of endogenous hormones in maize roots and leaves; P6 was the best treatment for improving the endogenous hormone contents in maize plants, P3 was the best for improving the maize grain yield. Overall, 40 kg ha−1 is recommended as the best P application rate under the experimental conditions, considering the economic cost and environmental effects.

System Productivity and Balance of Soil Phosphorus in Rice - Zero till Maize (Zea mays L.) Cropping System as Influenced by Levels of Phosphorus

Aims: To study the phosphorus requirement of Rice - zero till maize (Zea mays L.) cropping system on system productivity and soil available Phosphorus balance. Study Design: Randomized block design (two factors). Methodology: The field experiment was conducted for two consecutive years at the College of Agriculture, Rajendranagar, Hyderabad. Levels of P2O5 (kg ha-1) applied to rice (5 levels) and maize (3 levels) respectively were (P0-30, P0-45, P0-60, P10-30, P10-45, P10-60, P20-30, P20-45, P20-60, P30-30, P30-45, P30-60, P40-30, P40-45 and P40-60). Results: In terms of system productivity (maize grain equivalent yield kg ha-1 annum-1) of rice–maize cropping system, the P40-60 and P30-60 treatments were found better than other Phosphorus management strategies. The balance sheet of available Phosphorus in soil at the end of fourth season revealed that input-output balance was positive with P40-60 and P30-60 by specifying the application of 30 kg P2O5 ha-1 and/or 40 kg P2O5 ha-1 to rice and 60 kg P2O5 ha-1 to maize in rice-zero till maize cropping system.

Aflatoxin levels and Aspergillus species in maize in the Province of Isabela, Philippines

AbstractThe province of Isabela is the top maize producer in the Philippines. The intensive cultivation and the tropical climate in the region may favour fungal growth and aflatoxin contamination in maize grains. Thus, the study aimed to determine the occurrence of aflatoxin and mycotoxigenic Aspergillus species in maize varieties in this region. Samples were obtained in six municipalities from hybrid (Bt) maize (n = 101) and open‐pollinated varieties (n = 6) during the dry season (March and April) of 2019. Aflatoxin levels were quantified through enzyme‐linked immunosorbent assay, and Aspergillus species were identified through cultural and molecular methods. Aflatoxin was detected in 50.5% of maize samples; 49.5% of samples were less than the limit of detection (3 μg/kg), 16.8% with 3–20 μg/kg, 10.9% with 21–50 μg/kg and 22.8% above 50 μg/kg. Samples within the acceptable level were 66.3% for food (&lt;20 μg/kg) and 77.2% for animal feed (&lt;50 μg/kg), while 22.8% of samples were above the acceptable level of the Philippine National Standard for raw maize grains. More than 90% of Aspergillus species detected were A. flavus. Other species identified were A. tamarii and A. terreus. Despite the dry production season in the province with low relative humidity during harvesting, inadequate post‐harvest practices and the presence of A. flavus elevated the level of aflatoxin in sample grains. Additional work involving multi‐year surveys is needed to confirm the results and conclusions of this study.

Major Fusarium species and mycotoxins associated with freshly harvested maize grain in Uruguay.

Fusarium species are common fungal pathogens of maize. Fusarium graminearum and Fusarium verticillioides, among others, can cause maize ear rot, and they are also mycotoxin producers. The aims of this work were to determine the frequency and diversity of Fusarium species in Uruguayan maize kernels, evaluate the toxigenic potential of the isolates, determine toxin contamination levels on freshly harvested grain, and assess the sensitivity of main Fusarium species against fungicides. Fusarium verticillioides was the most frequent species isolated, followed by Fusarium graminearum sensu stricto. Of F. verticillioides isolates studied for fumonisin production, 72% produced fumonisin B1 and 32% fumonisin B2. Considering in vitro toxin production by F. graminearum sensu stricto isolates, deoxynivalenol was the main toxin produced, followed by zearalenone and nivalenol. Fumonisins were the most frequently found toxins on freshly harvested maize samples (98% in 2018 and 86% in 2019), and also, fumonisin B1 was the toxin with highest concentration in both years studied (4860µg/kg in 2018 and 1453µg/kg in 2019). Deoxynivalenol and zearalenone were also found as contaminants. Metconazole and epoxiconazole were the most effective fungicides tested on F. verticillioides isolates. Fusarium graminearum sensu stricto isolates also were more sensitive to metconazole compared to other fungicides; nevertheless, epoxiconazole was less efficient in controlling this species. This is the first study that reports Fusarium species and mycotoxin contamination levels associated with maize grain in Uruguay. Its detection is the main step to develop management strategies in order to minimize fungal infection in maize crops.

Combining ability of experimental maize lines for yield and aflatoxin in the southeastern United States

AbstractAflatoxin contamination of maize (Zea mays L.) grain presents risks to animal and human health and causes economic losses for growers, particularly in the southeastern United States. Development of hybrids with genetic resistance to aflatoxin contamination by Aspergillus flavus will reduce these risks. Two factorial crossing experiments were conducted to evaluate yield, agronomic traits, and aflatoxin in maize hybrids. In Experiment 1, 18 aflatoxin‐resistant (GT) lines were each crossed to six testers. In Experiment 2, 13 of the same lines were each crossed to 10 different testers. Each experiment was conducted for 2 years at Tifton, GA, and commercial check hybrids were included for comparison. Ears were inoculated with A. flavus isolate NRRL 3357 using the side‐needle technique 14 days after silking. Aflatoxin was quantified after harvest. Broad sense heritability for aflatoxin was low in Experiment 1 (H2 = 0.09) but was higher in Experiment 2 (H2 = 0.27). Heritability was moderate to high for plant height (H2 = 0.49–0.51) and days to silking (H2 = 0.54–0.72). Among experimental lines, GT1209 and GT1309 had consistent positive general combining ability (GCA) for yield, whereas GT1203 and GT1204 had consistent negative (favorable) GCA for aflatoxin. Significant GCA effects, both positive and negative, for aflatoxin were also observed among testers in both experiments. Some experimental hybrids had yields that were comparable to commercial checks while also having lower aflatoxin, demonstrating the progress made in improvement of both traits in maize hybrids adapted to the Southern United States.

Assessment of the Rhizosphere Bacterial Community under Maize Growth Using Various Agricultural Technologies with Biomodified Mineral Fertilizers

Biomodified mineral fertilizers (BMFs) were produced by enriching the ammophos fertilizer with PGPR Bacillus velezensis BS89 with the use of two technologies: BMF 1, the ammophos fertilizer with the addition of spores of Bacillus velezensis BS89 on a dry carrier (diatomite); and BMF2, ammophos granules treated with spores of Bacillus velezensis BS89 in a cell suspension. The effects of BMFs on maize growth and productivity and the rhizosphere bacterial community were assessed. BMFs significantly increased maize growth, dry matter, minerals, starch and protein contents in maize grain. The application of biomodified mineral fertilizers resulted in the significant increase in the yield and some parameters of maize plants such as ear length and number of kernels in the row. The yield was increased by 7.5–7.6%, ear length by 9%, and number of kernels in the row by 6.7–7%, as compared with ammophos. However, we found no considerable differences in the composition of the bacterial community of the maize rhizosphere after the use of BMFs as compared with the use of ammophos at the level of the phyla, which was confirmed by the ecological indices of biodiversity: the Shannon index and the Simpson index. Comparison of the experimental variants with bulk soil showed differences in the microbiome composition of the dominant bacterial phyla. A greater abundance of Proteobacteria and Bacteroidetes and a lower abundance of Chloroflexi was registered in bulk soil as compared with the other experimental variants where maize plants were present. The highest percentage (5.3%) of unidentified taxonomic phyla was also found in bulk soil. Our studies showed that maize is the main structuring factor during formation of the microbiome composition in the rhizosphere. The application of biomodified fertilizers BMF1 and BMF2 considerably increased the abundance of bacteria representing the minority of the community, namely, those from the phyla Verrucomicrobia, Chloroflexi, Planctomycetes, Proteobacteria, Firmicutes and Chlamydiae, as compared with the use of ammophos. Thus, the application of biomodified mineral fertilizers is a promising agronomic and ecological strategy for boosting maize yield and the quality of grain under field conditions.

Development of biologically engineered corn growing technologies

Agricultural producers use large quantities of mineral fertilisers and plant protection products, which leads to soil, seed and environmental pollution and reduces the profitability of production. Modern agriculture starts to shift its focus to biologisation, which includes the development and implementation of environmentally friendly alternative systems, the reduction of chemicals, the introduction of energy and resource-saving technologies, use of biological plant protection products and bio-organic fertilisers. The research aims to investigate the effectiveness of biological technologies for growing maize in an environmentally friendly way using various organic fertilisers. The following methods were used to study the new corn growing technology: analysis, synthesis, analogy, comparison, and generalisation; field and laboratory; calculation – assessment of economic and bioenergy efficiency. To study the effect of organic fertilisers of different biological origins on the assessment of the humus state of typical chernozems, field experiments were conducted to assess the impact on corn grain yield in the Ukrainian Steppe. After the application of organic fertiliser, the limits of organic carbon content in humus were 3.2-3.5%, humic acid 1.9-2.2%, and fulvic acid 0.7-1.0%. In the experimental samples of maize grain, the content of crude protein ranged from 13.5 to 14.0%, crude fat from 2.4 to 2.7%, crude fibre from 2.1 to 2.4%, crude ash from 1.3 to 1.7%, and nitrogen-free extractives from 64.7 to 67.4%, moisture from 12.0 to 14.9%. The grain yield in the control variant was 9.7 t/ha, and in the experimental plots, it was 11.5-13.4 t/ha. The data obtained can help in the development of biologically based maize cultivation technology following the ecological gradient of cultivation and yield with optimisation of the studied agrotechnical methods

Efficacy of Botanical Extract Formulations of Zanthroxylum usambarense and Warburgia ugandensis on Post-Harvest Management of Sitophilus zeamais in Maize

Sitophilus zeamais causes significant losses to maize produce worldwide. The use of biodegradable and environmentally friendly botanicals as an alternative to synthetic pesticides is increasingly becoming important. Therefore, we sought to determine the use of plant extract formulations to manage S. zeamais during storage. Crude Zanthroxylum usambarense and Warburgia ugandensis stembark extracts were used for contact toxicity and repellent bioassays against S. zeamais. The formulations that exhibited the highest repellence and mortality were tested for insecticidal activity during storage for six months. Phytochemical profiles of the extracts were determined using GC-MS, and molecular docking of active compounds against insect target proteins was done. Mortality analyses revealed LD50 values of 114.89 µg/mL and 197.19 µg/mL for Z. usambarense’s hexane and methanol organic extracts, respectively. Warburgia ugandensis extracts had LD50 values of 69.25 µg/mL and 163.52 µg/mL, respectively. Extract formulations achieved weevil perforation index values of &lt;50.00 in all treatments. The docking analysis showed the pesticidal potential of several compounds, and mortality could be attributed to Eugenol (19.28%), 1,8-cineole (5.78%) and Linalool (21.42%). The tested botanicals have demonstrated their ability to suppress S. zeamais development in stored maize and could be utilized to protect maize grains during storage.

Maize Grain Germination Is Accompanied by Acidification of the Environment

Seed germination is a complex process involving several stages, starting with the imbibition of water and ending with the emergence of the radicle. In the current study, we address the observation of an unexpected pH shift during the imbibition of maize grains. We used direct pH measurements of soak water, the pH indicator methyl red, and anatomical analysis to shed light on the acidification associated with maize (Zea mays L.) germination, a largely overlooked phenomenon. Our work shows that acidification during imbibition of maize grains is a two-step process: (i) early, rapid acidification (pH values up to 4.4), in which protons stored in the (dead) pericarp/testa are mobilised and rapidly diffuse into the surrounding medium, and (ii) late, delayed acidification (pH values just below 6), starting hours after contact of grains with water, representing an active transport process caused by living cells of the seed. We discuss the physiological mechanisms and ecological relevance of environmental acidification during maize grain germination.

Preparation of Polyclonal Antibody against ZmBT1 Protein and Its Application in Hormone-Regulated Starch Synthesis

In order to investigate the crucial role of ZmBT1 in starch accumulation during maize grain development and analyze the expression and distribution of ZmBT1 in various maize tissues, we prepared a polyclonal antibody. Specifically, we successfully expressed the recombinant plasmid pGEX-6p-ZmBT1-C (382-437aa) and purified Gst-ZmBT1-C as the antigen for antibody preparation. Our results confirmed that the ZmBT1 protein in maize tissues can be specifically recognized by the ZmBT1 antibody. Through Western blotting, we observed that the expression protein of ZmBT1 varied by tissues, with the highest content in the grain and endosperm. Furthermore, we employed a combination of Western blotting and quantitative real-time PCR to show that the expression level of ZmBT1 can be influenced by plant hormones. This finding suggests that ZmBT1 plays a critical role in the accumulation of starch and opens up new avenues for functional studies of this protein.

Comprehensive analysis of transcriptional data on seed germination of two maize inbred lines under low-temperature conditions

Seed germination directly affect maize yield and grain quality. Low-temperature reduces maize yield by affecting seed germination and seedling growth. However, the molecular mechanism of maize seed germination under low-temperature remains unclear. In this study, the transcriptome data of two maize inbred lines SCL127 (chilling-sensitive) and SCL326 (chilling-tolerant) were analyzed at five time points (0 H, 4 H, 12 H, 24 H, and 48 H) under low-temperature conditions. Through the comparison of SCL127-0 H-vs-SCL326-0 H (Group I), SCL127-4 H-vs-SCL326-4 H (Group Ⅱ), SCL127-12 H-vs-SCL326-12 H (Group Ⅲ), SCL127-24 H-vs-SCL326-24 H (Group Ⅳ), and SCL127-48 H-vs SCL326-48 H (Group Ⅴ), a total of 8,526 differentially expressed genes (DEGs) were obtained. Weighted correlation network analysis revealed that Zm00001d010445 was the hub gene involved in seed germination under low-temperature conditions. Zm00001d010445-based association analysis showed that Hap Ⅱ (G) was the excellent haplotype for seed germination under low-temperature conditions. These findings provide a new perspective for the study of the genetic architecture of maize tolerance to low-temperature and contribute to the cultivation of maize varieties with low-temperature tolerance.