Maize Production Systems Research Articles

Evaluating the impact of weather forecasts on productivity and environmental footprint of irrigated maize production systems

Integrating weather forecasts into decision support systems empowers farmers to optimise irrigation schedules, thereby boosting crop yields and conserving water. However, inaccurate forecasts can jeopardise productivity and irrigation efficiency. This study combines a crop model with a stochastic pseudo-weather forecast algorithm to: (1) determine the reliability needed in a weather forecast algorithm for effective irrigation management; and (2) assess the impact of weather forecast reliability on the productivity and environmental footprint of various maize cropping systems across diverse climates. It employs the Next Generation of Agricultural Production Systems sIMulator (APSIM NextGen) to simulate maize growth at eleven locations representing diverse climates globally. Various planting schedules, soil types, irrigation systems, and nitrogen availability levels were considered to examine the effects of perfect and imperfect weather forecasts. The findings underscore the potential of integrating weather forecasts into irrigation management for enhanced productivity and sustainability. High-confidence forecasts and longer lead times increase yields (up to 11 %) and improve sustainability outcomes, particularly in wetter climates and for conditions with low nitrogen availability. Conversely, when the accuracy of forecasts is low, forecast-driven irrigation management may lead to yield reductions compared to a baseline system, especially in drier climates (up to 26 % reduction), necessitating tailored management strategies. Soil type and farmer's risk tolerance further influence the effectiveness of forecast-driven irrigation management, emphasising the need for context-specific approaches. By understanding and leveraging the interconnected impacts of weather forecasts on yield, water use efficiency, nitrogen loss, and greenhouse gas emissions, farmers can optimise productivity while minimising environmental impacts.

Using Unmanned Aerial Systems Technology to Characterize the Dynamics of Small-Scale Maize Production Systems for Precision Agriculture

Precision agriculture (PA) utilizes spatial and temporal variability to improve the sustainability and efficiency of farming practices. This study used high-resolution imagery from UAS to evaluate maize yield variability across three fields in Ghana: Sombolouna, Tilli, and Yendi, exploiting the potential of UAS technology in PA. Initially, excess green index (EGI) classification was used to differentiate between bare soil, dead vegetation, and thriving vegetation, including maize and weeds. Thriving vegetation was further classified into maize and weeds, and their corresponding rasters were developed. Normal difference red edge (NDRE) was applied to assess maize health. The Jenks natural breaks algorithm classified maize rasters into low, medium, and high differential yield zones (DYZs). The percentage of bare spaces, maize, weed coverages, and total maize production was determined. Significant variations in field conditions showed Yendi had 34% of its field as bare, Tilli had the highest weed coverage at 22%, and Sombolouna had the highest maize crop coverage at 73.9%. Maize yields ranged from 860 kg ha−1 in the low DYZ to 4900 kg ha−1 in the high DYZ. Although yields in Sombolouna and Tilli were similar, both fields significantly outperformed Yendi. Scenario analysis suggested that enhancing management practices to elevate low DYZs to medium levels could increase production by 2.1%, while further improvements to raise low and medium DYZs to high levels could boost productivity by up to 20%.

Crop establishment and nutrient management options: Optimizing productivity, maximize profitability and mitigating adverse climatic conditions in the maize-based production system of Northwest India

Poor fertilizer management and intensive tillage have increased production costs, lowered productivity, and significantly depleted soil nutrients. Although nutrient management options (NMOs) within crop establishment options (CEOs) based maize production system (MPS) is seldom explored, CEOs is increasingly advocated to tackle problems with soil health, food security, and climate change. Developing and implementing effective NMOs is needed for improving system sustainability, profitability, and productivity. We evaluated the effects of CEOs and NMOs on nutrient acquisition, profitability, and maize productivity in the Northwestern Indo-Gangetic Plains (IGPs) of India during 2018–2019. In this study, four CEOs treatment [(i) conventional tillage without residue {CT–R}, (ii) conventional tillage with residue {CT+R}, (iii) permanent raised bed without residue {PRB–R}, and (iv) permanent raised bed with residue {PRB+R}], were kept in the main plot and three NMOs [(i) soil test-based recommendation {STBR}, (ii) nutrient expert-based recommendation {NE}, and (iii) NE with GreenSeeker {NE+GS} were tested in subplots. The results showed that the crop growth metrics, including plant height, dry matter accumulation, leaf area index, and crop growth rate, were significantly greater at PRB+R comparing to treatments. Additionally, PRB+R resulted in the shortest time to 50 % and 75 % silking, indicating enhanced crop development. NMOs significantly improved crop growth parameters. The NE+GS treatment recorded higher plant height (145.8–149.2 cm and 222.3–224.8 cm), dry matter accumulation (195.5–198.4 g/m² and 408.4–412.0 g/m²), leaf area index (2.45–2.48 and 3.24–3.30), and crop growth rate (6.50 and 7.10 g/m²/day). PRB+R showed the shortest silking times (60.5 and 62.2 days). PRB+R also attained the maximum maize yield (6.23 and 6.26 t/ha), by a 17.82 % and 17.57 % increase over CT–R in 2018 and 2019. The NE+GS treatment resulted in the highest maize productivity, with additional yield gains over NE alone and STBR. The lowest cultivation cost ($513.87/ha and $513.97 /ha), highest net return ($1028.91/ha and $1083.60/ha), and best benefit-cost ratio (2.00 and 2.11) were observed with PRB–R, while gross returns ($1573.78/ha and $1630.42/ha) had highest in PRB+R. The NE+GS option achieved higher gross returns ($1544.73/ha and $1599.37/ha), net returns ($918.29/ha and $977.30/ha), and benefit-cost ratios (1.47 and 1.57) with lower cultivation costs ($626.43/ha and $622.06/ha) compared to NE and STBR. The PRB+R and NE+GS combination had found highest nutrient uptake (N, P, K) in grain and straw, highlighting their effectiveness in nutrient management. Overall, our findings recommend adopting PRB+R and NE+GS to optimize maize production system productivity and profitability, ensuring agricultural sustainability and resilience to adverse climatic conditions in Northwest India.

Short‐statured maize achieved similar growth and nitrogen uptake but greater nitrogen efficiencies than conventional tall maize

AbstractDespite a historical favoring of robust tall plants in maize (Zea mays L.) production systems as a potential indicator of increased total and/or grain biomass yields, short‐statured maize is receiving renewed commercial attention in North America. Little is known of the relative N efficiencies resulting from potential inter‐stature differences in dry matter formation and N processes during pre‐ and post‐silking stages. To investigate this, two field rainfed experiments were conducted in West Lafayette, IN. The experiments included factorial combinations of two tall‐ and two short‐statured maize hybrids subjected to three N rates: 0 (unfertilized), 168 (moderate), and 224 kg N ha−1 (elevated) applied at planting. Short hybrids with a 25% reduced stature showed no statistically significant differences in seasonal biomass accumulation and N uptake, or in biomass partitioning to grain (harvest index) versus stover at maturity relative to conventional tall hybrids. Increased leaf biomass and ear growth at silking, plus comparable quantities of N remobilization from stems during grain filling, with short‐stature maize contributed to its grain yield parity with tall‐stature maize. Additionally, our research revealed other noteworthy findings: short‐statured maize had higher N harvest index and N recovery efficiency than the tall maize, implying more N status resiliency at moderate N rates. The lack of interactions between N × stature in most studied traits suggests that short hybrids can perform at least as well as conventional tall hybrids across a range of N rates. Our findings provide insights for fine‐tuning of breeding and management programs.

Impact of Crop Residue, Nutrients, and Soil Moisture on Methane Emissions from Soil under Long-Term Conservation Tillage

Greenhouse gas emissions from agricultural production systems are a major area of concern in mitigating climate change. Therefore, a study was conducted to investigate the effects of crop residue, nutrient management, and soil moisture on methane (CH4) emissions from maize, rice, soybean, and wheat production systems. In this study, incubation experiments were conducted with four residue types (maize, rice, soybean, wheat), seven nutrient management treatments {N0P0K0 (no nutrients), N0PK, N100PK, N150PK, N100PK + manure@ 5 Mg ha−1, N100PK + biochar@ 5 Mg ha−1, N150PK+ biochar@ 5 Mg ha−1}, and two soil moisture levels (80% FC, and 60% FC). The results of this study indicated that interactive effects of residue type, nutrient management, and soil moisture significantly affected methane (CH4) fluxes. After 87 days of incubation, the treatment receiving rice residue with N100PK at 60% FC had the highest cumulative CH4 mitigation of −19.4 µg C kg−1 soil, and the highest emission of CH4 was observed in wheat residue application with N0PK at 80% FC (+12.93 µg C kg−1 soil). Nutrient management had mixed effects on CH4 emissions across residue and soil moisture levels in the following order: N150PK > N0PK > N150PK + biochar > N0P0K0 > N100PK + manure > N100PK + biochar > N100PK. Decreasing soil moisture from 80% FC to 60% FC reduced methane emissions across all residue types and nutrient treatments. Wheat and maize residues exhibited the highest carbon mineralization rates, followed by rice and soybean residues. Nutrient inputs generally decreased residue carbon mineralization. The regression analysis indicated that soil moisture and residue C mineralization were the two dominant predictor variables that estimated 31% of soil methane fluxes in Vertisols. The results of this study show the complexity of methane dynamics and emphasize the importance of integrated crop, nutrient, and soil moisture (irrigation) management strategies that need to be developed to minimize methane emissions from agricultural production systems to mitigate climate change.

Genome edited zm-D8 reduced stature maize hybrids have improved climate resilience and competitive yields

As the frequency of intensive storm events increases in the U.S. Corn Belt, reduced stature maize hybrids could provide a new approach to improved climate resilience in maize production. We designed gene-edited D8 (dwarf8, zm-D8) maize germplasm with reduced stature to evaluate morphometric traits and grain yield. Four elite edited zm-D8 maize hybrids and their isogenic standard height hybrid comparators were evaluated over a total of 17 field locations in 2021 and 2022. Across three plant densities (80 K, 100 K and 120 K plants ha−1), plant height of the edited zm-D8 reduced stature hybrids was reduced 34 % and ear height was decreased 32 %. In each of the three plant densities, grain yield of the edited zm-D8 reduced stature hybrids was comparable to the isogenic standard height hybrids. Also, edited zm-D8 hybrids had significantly less lodging than the standard hybrids. In a separate study, DP202216 (ZmGos2:zmm28) a transgenic event with increased and extended expression of the zmm28 transcription factor, was crossed with reduced stature edited zm-D8 hybrids. Combining edited zm-D8 with event DP202216 significantly increased hybrid yields over those of edited zm-D8 hybrids under high density (120 K plants ha−1). These results support a maize production system where edited zm-D8 reduced stature hybrids, alone or in combination with DP202216, provide improved climate resilience with grain yields competitive to standard height hybrids.

Nitrogen rate is more important than irrigation rate in mitigating nitrogen leaching in flood-irrigated maize: A 6-year lysimeter experiment

Excessive nitrogen (N) fertilization and irrigation prevail in irrigated agriculture worldwide. However, little information is available that systematically evaluates grain yield, plant N uptake, residual soil NO3−-N (RSN), and N leaching under different irrigation–N regimes in an irrigated maize production system. To address such agronomic and environmental issues, a 6-year in situ lysimeter field trial was conducted in the Hetao Irrigation District of China with five treatments: 1) conventional irrigation (3,900 m3/ha) and local farmer fertilizer N rate (490 kg ha−1) (CON); 2) conventional irrigation and the recommended fertilizer N rate (420 kg ha−1) (RN); 3) deficit irrigation (2,730 m3/ha) and the recommended fertilizer N rate (SRN); 4) deficit irrigation and the recommended fertilizer N rate (with ∼ 10 % organic fertilizer N substitution) (SMN); and 5) conventional irrigation and controlled-release N fertilizer (270 kg ha−1) (CRF). Maize yield was not significantly different across treatments in 2015–2020. Averaged across years, SMN, SRN, and CRF significantly increased plant N uptake compared with that in CON by 28.84 %, 19.15 %, and 17.53 %, respectively. Residual soil NO3−-N at 0–90 cm was ranked as SRN > CON ≈ SMN > RN > CRF, whereas cumulative N in leachate from 2015–2020 (Nloss) in CON was 86.2 % to 187.1 % higher than that in other treatments. The Nloss in SRN was equivalent to that in RN and SMN, but Nloss in SMN decreased significantly compared with that in RN, indicating additive benefits of deficit irrigation and organic input on reducing N leaching. Structural equation modelling revealed that irrigation had greater effects on plant N uptake than those of fertilization, whereas N rate had a greater total effect on N leaching than that of irrigation. Overall, rampant excessive irrigation and N fertilization by farmers can be substantially reduced while maintaining grain yield and mitigating N leaching loss, with further benefits gained by applying controlled-release N fertilizer and manure in irrigated maize production.

Fresh or dry maize or both: Which is most economical and preferred by farmers?

As a staple crop of great importance in sub-Saharan Africa, maize is essential for the production of food for humans and animals, particularly in the raising of poultry and livestock. Smallholder farmers in Ghana are the main producers of maize, and they frequently have difficulties in turning their crop into a sustainable source of income. As a result, there is an increasing need for these farmers to look into other options such as switching from traditional dry maize production to growing fresh maize. This circumstance calls for a critical analysis to ascertain whether producing for fresh or dry maize markets yields higher profitability. Therefore, the main objective of this study is to estimate the profitability of Ghana's fresh and dry maize markets, examine the factors influencing farmers' market choices as well as rank the production constraints. Data was collected from 390 maize farmers using questionnaires. Gross margin analysis, multinomial logit regression and Kendall's Coefficient of Concordance, were the methods of analysis. According to the study, fresh maize yields a profit of 78.00 pesewas for every GH¢ 1.00 invested, both alternatives generate 71.00 pesewas, and dry maize yields 67.00 pesewas. This implies that even though all three businesses are profitable, fresh maize cultivation stands out as the most lucrative. The results of the multinomial logit regression analysis showed that the choice of maize production systems is influenced by socioeconomic characteristics, farming experience, and loan availability. The Kendall's Coefficient of Concordance analysis confirms consensus on constraints, with lack of finance, pest issues, poor roads, and low maize prices as key challenges. According to the report, farmers may increase their profits by diversifying their crops to include the fresh maize market. Additionally, the government could assist these farmers by making financing more accessible to them through collaborations with financial institutions and specially designed agricultural loan programs.

Predictive Potential of Maize Yield in the Mesoregions of Northeast Brazil

Most of the northeastern region of Brazil (NEB) has a maize production system based on family farming, with no technological advances and totally dependent on the natural rainfall regime, which is concentrated in 4 to 5 months in most parts of the region. This means that the productivity of this crop is low in the NEB. In the northern mesoregions of the NEB, rainfall is concentrated between January and June, in the east of the NEB from April to September, and in the west of the NEB from October to March. The growing season takes place during these semesters. With this in mind, our objective was to develop a model based on canonical correlation analysis (CCA) to predict corn production in the mesoregions of the NEB between 1981 and 2010, using accumulated precipitation per semester as the predictor variable and predicting the observed production in kg/ha. Our results showed that the CCA model presented higher correlations between observed and simulated production than that obtained simply from the direct relationship between accumulated rainfall and production. The other two metrics used, RMSE and NRMSE, showed that, on average, in most mesoregions, the simulation error was around 200 kg/ha, but the accuracy was predominantly moderate, around 29% in most mesoregions, with values below 20% in six mesoregions, indicative of better model accuracy, and above 50% in two mesoregions, indicative of low accuracy. In addition, we investigated how the different combinations between two modes of climate variability with a direct influence on precipitation in the NEB impacted production in these 30 years, with the combination of El Niño and a positive Atlantic dipole being the most damaging to harvests, while years when La Niña and a negative Atlantic dipole acted together were the most favorable. Despite the satisfactory results and the practical applicability of the model developed, it should be noted that the use of only one predictor, rainfall, is a limiting factor for better model simulations since other meteorological variables and non-climatic factors have a significant impact on crops. However, the simplicity of the model and the promising results could help agricultural managers make decisions in all the states that make up the NEB.

Plant nutrient removal and soil residual chemical properties as impacted by maize planting date and density.

This study aimed to measure maize (Zea mays) plant nutrient content and nutrient removal in grain, and to evaluate the residual soil nitrogen, phosphorus, and potassium as impacted by planting date and density. Field experiments were conducted to evaluate six plant densities and seven planting dates using a split-split plot design with three replications. Besides the crop growth and yield parameters, six plants were collected at the maturity and soil was sampled from each plot for nutrient analysis. Plant N, P, and K concentrations varied with planting date and density and within the ranges of 0.6-1.024%, 0.054-0.127%, and 0.75-1.71%, respectively. Grain N, P, and K concentrations decreased with plant density and varied from 1.059 to 1.558%, 0.20 to 0.319%, and 0.29 to 0.43%, respectively. Soil residual nutrient varied with depth, planting density and date. Residual N concentration in the topsoil varied from 0.6 to 37.2 mg kg-1 in 2019 and from 1.5 to 11.2 mg kg-1 in 2020 and was high under the last two planting dates. Soil residual N concentration was higher in the second layer than in the topsoil. The N concentration in the third layer varied from 0.1 to 33.2 mg kg-1 and was impacted by plant density. Topsoil P did not vary among planting dates and densities. The second and third soil layers P concentration was not affected. There was 83% increase in topsoil K in 2020 compared to 2019, and a decrease of 65 and 23% in soil K was observed in the second and third soil layers, respectively. For maize production system sustainability, future research should use a holistic approach investigating the impact of planting date, plant density on crop growth, yield, nutrient uptake and remobilization, and soil properties under different fertilizer rates to develop the fertilizer recommendation for maize while reducing the environmental impact of the production system.

The milpa agroecosystem: A case study in Puebla, Mexico

In the Totonacapan region of northeastern Puebla, Mexico, two maize production systems are prevalent: the milpa and the maize field (maizal). The milpa system is an emblematic agroecosystem which focuses on traditional food production for self-consumption, utilising crop and land rotation to contribute to its sustainability and coexistence with native ecosystems. Adopted for commercial purposes, the maize field is the result of the government’s modernisation of traditional agriculture. The article examines why the milpa system persists over the maize field in the same cultural and environmental space, exploring the benefits and costs of both systems. The milpa system involves the cultivation of maize along with other crops and perennial woody species. It supports food security, diversifies the diet, and generates income from surplus products. Fruit trees and woody perennials in the milpa strengthen soil fertility, control weeds, provide firewood, and serve as stakes or supports for beans and as retaining walls or windbreaks. The system also incorporates useful plants like nopal and maguey for multiple purposes, including food and medicine. In contrast, the maize field system is characterised by commercial maize production and the use of improved maize varieties. While it generates income, it lacks the diversity and sustainability of the milpa system. Farmers recognise the cultural value of native maize and the environmental benefits of the milpa system but find it challenging to transition back due to soil degradation and labour-intensive practices. The milpa agroforestry system ultimately persists thanks to its provision of traditional foods, economic benefits, and environmental advantages, unlike the maize field system which faces challenges related to monocropping and loss of cultural heritage.

CARACTERIZACIÓN DEL AGROECOSISTEMA CON MAÍZ NATIVO EN TEZONAPA, VERACRUZ, MÉXICO

<p><strong>Background:</strong> Agroecosystems (AE) have different technological, productive, economic and socio-cultural characteristics; therefore, it is important to characterize them to offer information for the design of focused agricultural policies, and that promote the development of the region. <strong>Objective:</strong> Characterize the AE with native maize in Tezonapa, Veracruz, based on socio-cultural, technical-productive, economic and environmental factors. <strong>Methodology:</strong> The study was carried out using the survey technique by the non-probabilistic snowball method. Ninety-seven native maize producers were surveyed in 29 Tezonapa communities in 2020. The questionnaire was semi-structured with 53 questions in five sections, including producer data, as well as socio-cultural, technical-productive, environmental and economic. The data obtained from the questionnaires were captured in the Microsoft Office Excel<sup>®</sup> 2019 computer program, subsequently, a principal component analysis (PCA), descriptive statistics and a dendrogram were executed. For the typology of maize production systems, the 53 original variables were used, generating a dendrogram. <strong>Results:</strong> Two types of AE were found: Traditional (T) and Traditional Subsistence (TS) with differentiated technical-productive, socio-cultural, economic and environmental characteristics. According to the PCA, the most significant variables in the description of the AEs were two sociodemographic, five technical-productive, and three economic. <strong>Implications:</strong> The producers of Tezonapa must organize themselves for the management of innovations that impact the yield of native maize crop, but taking into account their knowledge about sustainable agricultural practices. <strong>Conclusions:</strong> The AEs studied, although they present technical-productive and economic limitations, also have benefits when providing food, generating and exchanging empirical knowledge, which has allowed the conservation of native maize, and said valuable knowledge must be rescued and promoted. </p>

Reducing energy and carbon footprint in semi-arid irrigated cropping systems through crop diversification

Energy and carbon (C) footprints of agricultural production practices have garnered high attention due to rising energy costs and increasing global warming. However, the contribution of conservation and regenerative farming practices, including cover cropping, on energy and C footprints have not yet been documented for cropping systems in arid and semi-arid regions. This study evaluated the energy and C footprint of cover crop integrated silage maize (Zea mays L.) and sorghum (Sorghum bicolor L. Moench) production systems in the semi-arid region of the southwestern US. The treatments were mixtures of winter cover crops: i) grasses and legumes (GL), ii) grasses, brassicas, and legumes (GBL), iii) grasses and brassicas (GB), and iv) no cover crops (NCC) control for each crop production system. Results showed cover crops had 24.1–24.5% greater energy input than NCC. In silage maize rotation, energy output was 17–22% greater in GBL and GL than in NCC. In silage sorghum rotation, the energy output was 15–24% greater in all cover crops than in NCC. The resulting net energy was 16–21% greater in GBL and GL than in NCC under silage maize, while it was 18–24% greater in GBL and GB than in NCC under silage sorghum. In the silage maize system, the C-footprint per kg yield was not different among treatments, whereas in silage sorghum, it was 58% greater in GBL than in NCC. The benefit-to-cost ratio was greater than one for all treatments, but the additional revenue through C credit programs could make cover cropping a more feasible and beneficial approach, improving economic and environmental sustainability while producing silage crops. While the C footprint was crop rotation specific, cover cropping should be encouraged over crop-fallow systems to producers in semi-arid environments to reduce energy usage and increase C-credit benefits. Clear national and state policy on the C credit program will also enhance economic and environmental benefits by adopting cover cropping and other regenerative farming practices.

ICT4Agroecology part II: outcomes for maize production systems

ABSTRACT Agroecology is gaining increased attention by experts and global organizations; however, it’s practical application in the field remains understudied, particularly in developing countries. Here, we aimed to evaluate common agroecological practices at three sites in Tanzania, including organic soil amendments, intercropping, and biological pest control – individually, in pairs, or in three-way combinations at each site. Information Communication Technology tools – the AgroEco Research and AgroEco Analysis application – were used for data gathering & storage and data visualization & statistical analysis, respectively. We found that high maize kernel weights (as proxy for yield) can be obtained from nutrient-poor soils specifically when grown with a combination of organic soil amendments and intercropped with legumes – ranging from 3 to 4.5 t/ha (with a maximum of 7 t/ha on one occasion) and exceeding national maize yields of 1–2 t/ha in Tanzania. However, intercropping and biological pest control individually and in combination did not affect maize yield. Under flood or drought conditions, only plots with soil fertility amendments produced some harvestable maize kernels. Our results provide a substantial reference for recommending and advocating agroecological methods to smallholder farmers, farmer training organizations, and policy makers.

Comparison of the AquaCrop and CERES‐Maize models for simulating maize phenology, grain yield, evapotranspiration and water productivity under different irrigation and nitrogen levels

AbstractThe CERES‐Maize and AquaCrop models were evaluated for their performance in simulating maize (Zea mays L.) phenology, evapotranspiration (ETc), grain yield and crop water productivity (CWP). Model input data for calibration, validation and simulations were obtained from field experiments conducted from 2011 to 2014 that imposed three different irrigation levels (full irrigation treatment [FIT], limited irrigation treatment [75% FIT] and rainfed control) and five nitrogen (N) management treatments. Both models performed well in simulating the maize phenological stages, with simulated values being within 1–4 days of measured values for both models. Both models simulated grain yield well during the calibration with a normalized root mean squared error (RMSEn) of 5% (0.6 t ha⁻1) for CERES‐Maize and 8% (0.80 t ha⁻1) for AquaCrop. The model error for ETc varied from −2 to +14% for CERES‐Maize and ranged from −3 to +11% for AquaCrop. High N levels resulted in higher accuracy in predicting ETc. The AquaCrop model performed better than CERES‐Maize in simulating irrigated crop production under different N levels under rainfed conditions. The performance of both models for rainfed systems was poorer than their performance in irrigated systems, indicating that both models need further improvements in simulating rainfed maize production systems.

Lippia alba-a potential bioresource for the management of Spodoptera frugiperda (Lepidoptera: Noctuidae).

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), a threat to maize production systems, is a polyphagous pest of global significance. There is no registered bioinsecticide of botanical origin to provide green remedy against this pest of concern. The present study reports for the first time the potency of the polar and non-polar bioinsecticidal leads sourced from Lippia alba (Mill.) N.E. Br. leaves. Shade-dried leaves of L. alba were extracted and evaluated; based on preliminary bioassay, the ethyl acetate leaf extract of L. alba (LEAE) was found to be the most potent against FAW in the in vitro and in vivo studies. Ultraperformance liquid chromatography-quadrupole time-of-flight-mass spectrometric (UPLC-QToF-MS) analysis of LEAE revealed the rich chemical profile of 28 compounds, dominated by flavones, namely, naringenin, trihydroxy-dimethoxy flavone, and dihydroxy-trimethoxy flavone. Among others, glycosides, such as clerodendrin, calceolarioside E, forsythoside B, geniposide, and martynoside, and glucuronides, such as luteolin-7-diglucuronide, tricin-7-O-glucuronide, and luteolin-7-O-glucuronide, were also identified. LEAE exhibited exceptionally high in vitro [LC50 = 6,900 parts per million (ppm)] and in vivo (computed as damage score on a scale of 1-9) insecticidal activity against S. frugiperda, with no phytotoxicity at a dose as high as 20 times of LC50. LEAE also exhibited significant antifeedant, ovicidal, and growth regulatory activity at the 70-16,000 ppm (w/v) concentration range. In silico assessment revealed strong binding of martynoside, calceolarioside E, and forsythoside B with acetylcholinesterase-, sodium-, and chloride-dependent γ-aminobutyric acid (GABA) receptor and ryanodine receptor, respectively, facilitated by hydrogen bonds (conventional and C-H bonds) stabilized by hydrophobic pi-sigma, pi-pi stacked, pi-alkyl, and alkyl interactions. The present study established L. alba as a potential bioresource and secondary metabolite enriched LEAE as bioinsecticide for further product development.

Multiscale physiological responses to nitrogen supplementation of maize hybrids.

Maize (Zea mays) production systems are heavily reliant on the provision of managed inputs such as fertilizers to maximize growth and yield. Hence, the effective use of nitrogen (N) fertilizer is crucial to minimize the associated financial and environmental costs, as well as maximize yield. However, how to effectively utilize N inputs for increased grain yields remains a substantial challenge for maize growers that requires a deeper understanding of the underlying physiological responses to N fertilizer application. We report a multiscale investigation of five field-grown maize hybrids under low or high N supplementation regimes that includes the quantification of phenolic and prenyl-lipid compounds, cellular ultrastructural features, and gene expression traits at three developmental stages of growth. Our results reveal that maize perceives the lack of supplemented N as a stress and, when provided with additional N, will prolong vegetative growth. However, the manifestation of the stress and responses to N supplementation are highly hybrid-specific. Eight genes were differentially expressed in leaves in response to N supplementation in all tested hybrids and at all developmental stages. These genes represent potential biomarkers of N status and include two isoforms of Thiamine Thiazole Synthase involved in vitamin B1 biosynthesis. Our results uncover a detailed view of the physiological responses of maize hybrids to N supplementation in field conditions that provides insight into the interactions between management practices and the genetic diversity within maize.

Herbigation combined with plastic film mulching to control weeds in maize (Zea mays L.) fields in the Hexi Corridor region, Northwest China

Weeds pose the greatest problem to maize production systems using drip irrigation under plastic film mulching (DIPFM) in the Hexi Corridor Region (HCR), Northwest China. Herbicide application is an imperative farming operation to control weeds. An experiment was conducted to detect the efficacy and safety of two preemergence herbicide formulations, acetochlor·atrazine·2,4-D-ethylhexyl 66% SC and S-metolachlor 96% EC mixed with atrazine 90% WG, applied by drip irrigation (DA1 and DA2, respectively) combined with functional plastic film mulching in the first irrigation event after maize sowing in the HCR. The results indicated that the efficacies of DA1 and DA2 in the three experimental seasons were similar to those of the two herbicide formulations applied by traditional soil spraying with machines (farming practice, FP). Additionally, DA1 and DA2 combined with hyaline-black-hyaline alternating double-color film mulching decreased herbicide input to the field by 44.34% and 45.44%, respectively. Phytotoxicity under DA1 and DA2 was not significant in maize seedlings at 4–6 weeks after herbicide treatment. Silage yields and most harvest indexes under the DA1 and DA2 treatments were similar to and even higher than those of the FP and weed-free treatments. Treatment with DA1 increased some yield properties, which was favorable for maize plant resistance to adverse environmental conditions. This study may serve as a technological reference for the application of herbicides in DIPFM systems for weed control, and its results provide useful information regarding the use of combined mechanical and chemical strategies to manage weeds in maize production.

Impact-oriented assessment of carbon, water and energy footprints for maize production: a case study in Shandong, China

ABSTRACT The continuously increasing demands of food, feed and various corn-derived products accelerate the concern about the corn production on environment. Nevertheless, few researches simultaneously address the issue from different perspectives of carbon, water and energy as well as their temporal variations. Herein, a systematic cradle-to-gate life cycle assessment of maize production was conducted with a case study in Shandong, China. Different midpoint and endpoint indices including 10-year average data from 2011 to 2020 and their temporal variations were investigated. The contribution analysis of different processes to these indices revealed that irrigation dominated the midpoint of water scarcity, whereas the sum of direct consumption, fertilizer and diesel production contributed more than 80% to all the other indices. The sensitivity analysis also illustrated that these environmental indices can be reduced by as high as 4% when the aforementioned inputs were individually decreased by 5%. The temporal variation of the global warming potential, aquatic eutrophication and fossil depletion demonstrated that all the three indices were decreased by about 25.0%–31.7% over the last decade. Further persistent efforts to enhance mechanized operation efficiency and explore green and efficient methods for fertilizer and diesel production were highlighted. Moreover, implementations of rational agricultural management such as scientific fertilization and water-efficient irrigation were suggested, in order to have an eco-friendly maize production system.

A Review on Impact of Different Nitrogen Management Techniques on Maize (Zea mays L.) Crop Performance

Nitrogen (N), as a primary nutrient requirement of maize (Zea mays L.), plays a critical role in its development and productivity. Proper nitrogen management practices involve a delicate balance between providing an adequate amount of this nutrient and mitigating potential environmental impacts. When implemented effectively, these practices can significantly improve corn production. An adequate nitrogen supply promotes vigorous vegetative growth, contributing to strong stalks and an abundance of leaves, which are essential for maximizing the plant's photosynthetic capacity. This lush foliage, in turn, leads to increased photosynthesis and carbohydrate production, providing the energy maize needs throughout the reproductive stage to develop and fill its kernels. In addition, nitrogen is closely linked to kernel development. Well-timed and dosed nitrogen applications can result in larger, well-filled ears with plump kernels, ultimately increasing both the quantity and quality of the maize yield. Environmental considerations, such as reducing nitrogen runoff and greenhouse gas emissions, are important for maintaining ecosystems and mitigating climate change. Thus, this review article highlights the need for a holistic approach to nitrogen management, combining innovative techniques with sustainable agricultural practices, to ensure food security and environmental conservation in maize production systems.