Maize Crop Research Articles

Maize crop performance on different Agricultural Production Systems and co-inoculation with A. brasilense and T. asperellum

Considering the increasing global population and demand for food, it is crucial to adopt agricultural practices that ensure both food security and environmental preservation. In this context, plant growth-promoting microorganisms (PGPM) and integrated crop-livestock-forestry systems (ICLF) have emerged as promising strategies for sustainable productive intensification. This research aimed to determine the effects of inoculating Azospirillum brasilense and Trichoderma asperellum on maize crops (Zea mays L.) grown in monocropping and ICLF systems. A complete randomized block design was performed in a 4 × 2 factorial arrangement with three replications. The crop systems included maize monocrop (C), crop-livestock (CL), crop-forest (CF), and crop-livestock-forest (CLF). Concomitantly, the co-inoculation (A. brasilense + T. asperellum) was compared to the control management (with no PGPM). CL and C systems with co-inoculation showed the highest yields, while the CF and CLF systems, which include the arboreal component, showed lower yields because of tree shading. CL + co-inoculation treatment was the most significant with increases of 17.14% in shoot dry mass, 43% in 1000-grain weight, and 9.56% in yield (t ha-1) compared to the C + control treatment. Additionally, the CL + co-inoculation treatment overcame the CLF + control by 136.63% in yield. Results indicate that the PGPM co-inoculation in maize within the CL system is an effective strategy for optimizing crop production.

Potato and Maize Plant Disease Detection Using Leaf Images

Plant diseases represent a serious threat to national productivity and global food security. Effective therapy for multiple diseases requires a precise and useful differentiation of them. In this work, a computerized system for the identification and categorization of diseases in potato and maize crops is developed using convolutional neural networks. The demonstration was created with the ResNet50V2 model and tested on a combined collection of images of leaves. The system achieved an astounding accuracy of 85.19. Enhancing model execution through exchange learning, fine-tuning, and information augmentation were all part of the process. With the use of another dataset, the trained model was verified and produced positive results, almost exactly differentiating between the disease-causing leaf type (potato or maize). This technology helps ranchers adopt sustainable and knowledgeable disease management methods by promoting timely mediations, which in turn advances disease discovery.

Enhancing Water Use Efficiency and Carbon Profitability Through the Long-Term Impact of Sustainable Farming Systems

This study aims to enhance water use efficiency, maximize productivity, and minimize environmental impact through the implementation of sustainable agricultural systems using drip irrigation systems. It investigates the effects of biodynamic farming compared to those of organic and conventional methods over a six-year period and focuses on soil properties, water use efficiency, crop yield, and environmental and economic perspectives. Using a biodynamic farming system resulted in an average increase in water use efficiency of 1.96 and 10.67% for maize and 3.62 and 10.68% for faba bean and an increase in maize yield of 1.68 and 0.99%, while the faba bean yield reached 3.25 and 1.57% compared to the organic and conventional farming systems, respectively. The biodynamic system sequestered the highest average soil carbon of 6.16 tons/ha (which is equivalent to 22.45 tons/ha of CO2 emissions), representing a 13% increase compared to the organic system. Additionally, the biodynamic system yielded an increase in total net profit of 5.70 and 21.66% for the maize crop and 6.72 and 22.19% for the faba bean crop compared to the organic and conventional farming systems, respectively. The farming system significantly influenced the soil carbon sequestration and organic carbon.

Data-Driven Prediction of Nitrogen Stress and Crop Yield in a Maize -Wheat Cropping System

The study has attempted to determine leaf-N content in a cropping system consisting of Wheat and Maize using plant sensors like GreenSeeker and SPAD meter (chlorophyll meter) and use machine learning models so that crop yields based on inputs can be predicted of data on nitrogen doses, NDVI values, SPAD values, and leaf N content. The data recorded from field experiments on wheat and maize crop variable fertilized by N (wheat: 0, 30, 60, 90, 120, 150, 180 and 240 kg N/ha; maize: 40, 80, 120, 160, 200, 240 and 300 kg N/ha) were used. A pair plot analysis showed a positive association between leaf N and NDVI, between leaf N and SPAD values, and between NDVI and SPAD values; all these parameters had a positive correlation with N- application rates. For yield prediction, the model calibrated for wheat could validate yield prediction for maize as well. Random Forest and Support Vector Machines showed reproducible performance (consistent) on both datasets (maize and wheat), with accuracies of 85.71% and 100%, respectively, on the original dataset.

GRASSIUS 2.0: A gene regulatory information knowledgebase for maize and other grasses

Grass species, which include the major cereal crops maize, wheat, rice, and sugarcane, are an integral part of our global agriculture and source of food and energy for a growing world population. GRASSIUS was established as a knowledgebase for transcription factors (TFs) and coregulators (CoRegs) in maize and several other species in the grass family. TFs are a primary component of the gene regulatory networks (GRNs) and the underlying gene regulatory grids (GRGs) that govern all aspects of plant growth and metabolism. GRASSIUS is the source for all information pertaining to the maize TFome collection, which serves as a powerful resource for the discovery of GRNs in maize and other cereals [1,2]. Here we describe the release of the GRASSIUS 2.0 knowledgebase (www.grassius.org) with updated data, query, and tool features, as well as the ability to expand to accommodate future datasets. The membership and annotation of all TF and CoReg families has been updated and revised to include gene models from v3, v4, and v5, of the maize B73 genome and recent genome versions of rice, sorghum, Brachypodium, and sugarcane. A translation tool enables cross referencing of Gene IDs between versions of the maize genome. Protein-DNA interactions (PDIs) have been added incorporating results derived from various gene- and TF-centered PDI discovery tools and visualized through a new web-based interface. A filtering tools permits the selection and visualization of PDIs within a ± 2 kb distance from the transcriptional start site (TSS) of a gene of interest. A new BLAST (Basic Local Alignment Search Tool) tool facilitates searching of the maize TFome as well as v3, v4, and v5 TF gene model sets. Lastly, we describe the methodology used to implement GRASSIUS 2.0 which can guide others in developing and updating similar plant gene regulatory knowledgebases.

Improved Agronomic Practices on Enhancement of Quality Forage Production for Livestock Farming

The lack of nutrient-rich fodder and forage is one of the problems of livestock farming. Adequate tillage operations, timely and suitable water management, weed management, insect pests and disease management, fertilizer management, seeding at the proper time and seed rate, timely harvesting, and other agronomic techniques can all help to increase the nutritional content and yield of fodder and forage crops. A number of research and review papers have been systematically reviewed in this study. The use of tillage practices such as primary, secondary, conventional, and deep tillage enhances dry matter and yield of green fodder as compared to zero tillage. The organic matter (OM) content and dry matter (DM) of fodder crops are increased by regular and appropriate irrigation. The DMD (dry matter digestibility) and CP (crude protein) contents of early harvested forages are higher than those of late harvested forages. The application of nitrogen promotes crop development and growth, increasing the production of green fodder and improving its quality. Intercropping is essential for increasing the yield of fodder crops. Compared to sole cropping of maize and cowpea, the yield is found higher in intercropping of maize + cowpea. The production and quality of fodder are decreased by late seeding. The management of insect pests and diseases enhances the production and quality of fodder and forage. Thus, we draw the conclusion that fodder and forage crops production and their quality parameters are greatly influenced by agronomic practices.

The effect of aeration and irrigation on the improvement of soil environment and yield in dryland maize.

The aim of this study was to examine the effect of long-term aerated seepage irrigation technology on soil fertility changes and maize yield under continuous maize cropping system in red loam soil, and to explain the mechanism of maize yield increase under this technology, which can provide theoretical basis for crop quality improvement and yield increase under aerated irrigation (AI) technology. Therefore, this research was conducted for four field seasons in 2020-2023 at the National Soil Quality Observation Experimental Station, Zhanjiang, China. Soil aeration, soil fertility, root growth, physiological traits, and yield indicators were evaluated by conventional underground drip irrigation (CK) and AI. Our results showed that AI treatment significantly improved soil aeration and soil fertility. Increases in soil oxygen content, soil respiration rate, soil bacterial biomass, and soil urease activity were observed, corresponding to increases from 3.08% to 21.34%, 1.90% to 24.71%, 26.37% to 0.09%, and 12.35% to 100.96%, respectively. The effect of AI on maize indicators increased year by year. Based on improvements in soil aeration and fertility, root length, root surface area, and root dry weight under AI treatment were enhanced by 15.56% to 53.79%, 30.13% to 62.31%, and 19.23% to 35.64% (p < 0.05) compared to the CK group. In addition, maize agronomic traits and physiological characteristics showed improved performance; in particular, over 1.16% to 14.42% increases were identified in maize yield by AI treatment. Further analysis using a structural equation model (SEM) demonstrated that the AI technology significantly promotes the improvement of root indicators by enhancing soil aeration and soil fertility. As a result, maize yield could be increased significantly and indirectly.

The Application of a Foliar Spray Containing Methylobacterium symbioticum Had a Limited Effect on Crop Yield and Nitrogen Recovery in Field and Pot-Grown Maize.

In this study, the effectiveness of an inoculant containing a nitrogen (N)-fixing microorganism (Methylobacterium symbioticum) was evaluated on maize (Zea mays L.) grown both in the field (silage maize) and in pots over two years (2021 and 2022). The field trial included the following two treatments: with (Yes) and without (No) the inoculant. The pot experiment was designed as a factorial arrangement with two factors: the application of the inoculant (Yes and No) and N applied to the soil (0, 0.4, 0.8, and 1.6 g pot-1). In the field, total dry matter yield (DMY) did not differ significantly between treatments, although the average DMY was higher in the inoculant treatment. In pots, the total DMY varied significantly across all N rates but was only significantly affected by the inoculant application in 2022. N fixation estimates in the field were 58.8 and 14.5 kg ha-1 for 2021 and 2022, respectively, representing 23.7% and 9.1% of the N recovered in the aboveground plant parts. In pots, the estimated fixed N values were -49.2 and 199.2 mg pot-1 in 2021 and 2022, respectively, which corresponded to -5.2% and 18.5% of the N found in the aboveground plant parts. Considering the average values obtained across the four cultivation conditions, there was a positive outcome for the treated plants. However, these values cannot be considered significant when compared to nitrogen removal in maize crops. A commercial product should provide an unequivocal and quantitatively relevant contribution to plant nutrition, which did not appear to be the case. Thus, for this inoculant to provide reliable guarantees of positive outcomes for farmers and become a useful tool in promoting more sustainable agriculture, further studies appear necessary. These studies should aim to determine in which crops and under what cultivation conditions the application of the inoculant is truly effective in enhancing N fixation and improving crop productivity.

Impact of biochar application on nitrous oxide and methane emissions in rainfed cropping systems within a semiarid region

AbstractThis study investigated the impact of biochar on Zea mays L. yield and greenhouse gas (GHG) emissions in rainfed maize fields in Northwest China. Four treatments were compared: unmodified control (CK), conventional nitrogen (BC0), nitrogen + 20 t ha−1 biochar (BC20), and nitrogen + 50 t ha−1 biochar (BC50). Results showed significant increases in grain yields with BC20 (11.1%) and BC50 (8.6%) compared to BC0. Emissions of nitrous oxide (N2O) were reduced by 14.0%–19.5% in biochar treatments compared to CK. Methane (CH4) uptake by the fields, acting as CH4 sinks, was not significantly impacted by biochar treatments, clarifying that the biochar did not alter the farmland's inherent ability to uptake CH4. Over 2 years, the addition of nitrogen fertilizer and biochar did not markedly alter cumulative CH4 uptake. Both net greenhouse gas (NGHG) emissions and yield‐scaled GHG intensity (NGHGI) were lowered by 16.7%–23.5% and 24.2%–30.3%, respectively, with biochar application. The integration of biochar effectively mitigated the GHG emission enhancement due to nitrogen fertilizer, mainly by decreasing nitrogen oxide emissions and boosting maize yields. Thus, proper biochar application would be an economical and effective strategy for mitigating gas emissions from rainfed maize cropping system in semiarid regions.

Impact of climatic trends on the water demand and irrigation planning for annual crops in the São Francisco River basin, Brazil

This study evaluated the spatial distribution of precipitation (P) and Peman-Monteith reference ET (ETo) in Brazil's São Francisco River basin (1961–2022). The analysis included Mann-Kendall trend tests and future IPCC projections on P and ETo to assess the need for supplemental irrigation (SI) of maize crop over twelve hypothetical growing seasons. The average annual P in the basin was 1300 mm year−1, decreasing from the Upper to the Lower section. Annual ETo averaged 1670 mm year−1, with higher depths in the Middle and Lower-middle sections. Trends for both P and ETo were significant(p < 0.05) in 58% of the basin. The overall trend magnitude in P was positive (average of about 0.5 mm year−2). Trend was decreasing in 56% of the sites (3.2 mm year−2) and increasing in 44% of them (5.3 mm year−2). For ETo, the overall trend was also positive (average of 3.0 mm year−2), with increasing trend in 79% of the sites (4.6 mm year−2) and a decreasing trend of 3.8 mm year−2 in 21% of the area. The need of SI varied both over the year with peaks in the May–August period and over the basin with higher depths in the Middle and Lower-middle sections. Large SI values (>800 mm) were associated with the dry season and areas with persistent trends in decreasing P and increasing ETo. Future IPCC projections indicate increased SI depths in most of the basin by 2081–2100, with the Middle and Lower-middle sections facing potentially unsustainable level for crop production.

A comparative study of crop evapotranspiration estimation in maize using empirical methods, pan evaporation and satellite-based remote sensing technique

A research study was conducted at the Agricultural College and Research Institute, Coimbatore to estimate the evapotranspiration (ET) of maize crop (Zea mays) over 2 consecutive seasons in 2022-2023. Among the different methods used to estimate crop evapotranspiration, the Food and Agricultural Organization Penman-Monteith model (FAO P-M) is widely recognized as the standard approach for ET estimation. This study aimed to compare the effectiveness of three alternative methods - Thornthwaite (TW), NDVI-based and pan methods against the FAO Penman-Monteith (P-M) model in estimating maize evapotranspiration. Meteorological data were collected from the TNAU weather station spanning the period from 2022 to 2023.The performance of the estimation methods was assessed using statistical metrics such as coefficient of determination (R2), root mean squared error (RMSE), percentage error and mean bias error. The findings revealed that the NDVI-based method, relying on satellite data, provided higher accuracy in estimating maize evapotranspiration compared to the FAO PM method. Specifically, the NDVI-based method achieved the highest coefficient of determination (R2) of 0.87 and 0.89, the lowest RMSE of 12.44 mm/month and 15.5 mm/month, the lowest percentage error of 4.8 % and 9.00 % and the lowest mean bias error of 5.5 and 7.85 for the first and second seasons respectively. This study highlights the effectiveness of the NDVI-based ET estimation method for accurately assessing maize evapotranspiration. While the FAO-56 Penman-Monteith method is highly regarded for its accuracy in both theoretical and practical contexts, the comparative evaluation presented in this paper offers valuable insights for selecting alternative methods that require less data, particularly in regions with limited data availability.

Automated lepidopteran pest developmental stages classification via transfer learning framework.

The maize crop is highly susceptible to damage caused by its primary pests, which poses considerable challenges in manually identifying and controlling them at various larval developmental stages. To mitigate this issue, we propose an automated classification system aimed at identifying the different larval developmental stages of 23 instars of 4 major lepidopteran pests: the Asian corn borer, Ostrinia furnacalis (Guenée; Lepidoptera: Crambidae), the fall armyworm, Spodoptera frugiperda (J.E. Smith; Lepidoptera: Noctuidae), the oriental armyworm, Mythimna separata (Walker; Lepidoptera: Noctuidae), and the tobacco cutworm, Spodoptera litura (Fabricius; Lepidoptera: Noctuidae). Employing 5 distinct Convolutional Neural Network architectures-Convnext, Densenet121, Efficientnetv2, Mobilenet, and Resnet-we aimed to automate the process of identifying these larval developmental stages. Each model underwent fine-tuning using 2 different optimizers: stochastic gradient descent with momentum and adaptive moment estimation (Adam). Among the array of models tested, Densenet121, coupled with the Adam optimizer, exhibited the highest classification accuracy, achieving an impressive 96.65%. The configuration performed well in identifying the larval development stages of all 4 pests, with precision, recall, and F1 score evaluation indicators reaching 98.71%, 98.66%, and 98.66%, respectively. Notably, the model was ultimately tested in a natural field environment, demonstrating that Adam_Densenet121 model achieved an accuracy of 90% in identifying the 23 instars of the 4 pests. The application of transfer learning methodology showcased its effectiveness in automating the identification of larval developmental stages, underscoring promising implications for precision-integrated pest management strategies in agriculture.

Modeling and Optimization of Maize Yield and Water Use Efficiency under Biochar, Inorganic Fertilizer and Irrigation Using Principal Component Analysis

This study was conducted to predict the grain yield of a maize crop from easy-to-measure growth parameters and select the best treatment combinations of biochar, inorganic fertilizer, and irrigation for the maize grain yield and water use efficiency (WUE) using the Principal Component Analysis (PCA) technique. Two rates of biochar (0 and 20 t ha−1) and fertilizer (0 and 300 kg ha−1) were applied to the soil, with maize crop planted, and subjected to deficit irrigation at 60, 80, and 100% of full irrigation amounts (FIA). Maize growth parameters (number of leaves—NL, leaf area—LA, leaf area index—LAI, and plant height—PH) were measured weekly. The results showed that the developed principal component regression (PCR) from the easy-to-measure growth parameters were strong and moderate in predicting the maize yield and WUE, with coefficient of determination; r2 values of 0.92 and 0.56, respectively. Using the PCA technique, the integration of irrigation with the least amount of water (60% FAI) with biochar (20 t ha−1) and fertilizer (300 kg ha−1) produced the highest ranking on grain yield and water use efficiency. This optimization technique showed that with the adoption of the integrative approach, 40% of irrigation water could be saved for other agricultural purposes

Effects of environmentally friendly soil remediation materials on soil quality and maize production

In the precent, the reclaimed raw soil of newly renovated abandoned homestead was considered as the research object, and study the effects of different environmentally friendly soil remediation material combinations on the quality of reclaimed raw soil and maize crop production. A total of 6 improved material treatments were set up, including decomposed chicken manure(YJ), fly ash(FMH), ferrous sulfate curing agent(SHJ), ferrous sulfate curing agent+organic fertilizer (SYJ), fly ash+decomposed chicken manure(FYJ), and control treatment(CK). The research results showed that, the organic carbon content and water storage of new reclaimed raw soil exhibited a significant increasing trend after the application of different environmentally friendly modified materials(P &lt; 0.05). Among them, the organic carbon and water storage of reclaimed soil under FYJ improved, which increased by 132.3 and 14.4 %, respectively compared with CK. During the growth period of summer maize, the plant height and yield exhibited a trend of FYJ&gt; SYJ&gt; YJ&gt; FMH&gt; SHJ&gt; CK. The yield of maize under SYJ and FYJ treatments increased by 38.8 and 53.4 %, respectively, compared with CK. The appropriate combination of environmentally friendly soil remediation materials is helpful to improve the quality of new reclaimed raw soil, promote soil carbon sequestration, increase the comprehensive utilization rate of waste resources, increase the production performance of crops, and help rural revitalization and beautiful rural construction. Bangladesh J. Bot. 53(3): 673-679, 2024 (September) Special

Exploring Natural Infection in Alternative Hosts of Corn Stunt Spiroplasma and Tracking the Temporal Dynamics of Corn Stunt Disease in the Brazilian Cerrado Biome

The corn stunt disease complex, caused by the mollicutes Spiroplasma kunkelii (Css) and the maize bushy stunt (MBS) phytoplasma, is a major phytosanitary issue for corn production in the neotropical region of Brazil. In this study, we investigated the presence of alternative hosts for S. kunkelii (Css) in the Brazilian Cerrado biome and explored the potential for asymptomatic Css infections in maize plants. To identify possible alternative hosts, we collected samples from ornamental and native plants located in Cerrado regions with a high incidence of corn stunt disease. We also monitored the disease’s progression over time and calculated the area under the disease progression curve (AUDPC). Additionally, we sampled healthy, asymptomatic maize plants growing near symptomatic ones and analyzed all the samples using qPCR to detect the pathogen. Our results showed no Css infection in the sampled alternative host species and no asymptomatic infections in the nearby maize plants. The incidence of maize stunting varied significantly among the sample years and counties. In Aparecida do Rio Negro, the infection rate was six times higher in 2020 compared to 2019, while Porto Nacional showed an 11-fold increase. During surveillance from March to July, the infection rate at the Sierra site went from less than 3% in March 2019 to 6% in July (F1,4 = 415.84; p = 0.0003). MBS infection increased significantly, while S. kunkelii remained stable below 3%. In 2020, MBS increased from 3% to more than 12%. A similar trend was observed at the Sede site, where MBS increased from 9% in 2019 to 11% in 2020. An increase in the AUDPC was observed both within individual years and between 2019 and 2020, indicating a worsening trend in disease severity. Overall, our findings reinforce the need for preventive measures in managing maize crop fields.

Maize Endophytic Plant Growth-Promoting Bacteria Peribacillus simplex Can Alleviate Plant Saline and Alkaline Stress.

Soil salinization is currently one of the main abiotic stresses that restrict plant growth. Plant endophytic bacteria can alleviate abiotic stress. The aim of the current study was to isolate, characterize, and assess the plant growth-promoting and saline and alkaline stress-alleviating traits of Peribacillus simplex M1 (P. simplex M1) isolates from maize. One endophytic bacterial isolate, named P. simplex M1, was selected from the roots of maize grown in saline-alkali soil. The P. simplex M1 genome sequence analysis of the bacteria with a length of 5.8 Mbp includes about 700 genes that promote growth and 16 antioxidant activity genes that alleviate saline and alkaline stress. P. simplex M1 can grow below 400 mM NaHCO3 on the LB culture medium; The isolate displayed multiple plant growth-stimulating features, such as nitrogen fixation, produced indole-3-acetic acid (IAA), and siderophore production. This isolate had a positive effect on the resistance to salt of maize in addition to the growth. P. simplex M1 significantly promoted seed germination by enhancing seed vigor in maize whether under normal growth or NaHCO3 stress conditions. The seeds with NaHCO3 treatment exhibited higher reactive oxygen species (ROS) levels than the maize in P. simplex M1 inoculant on maize. P. simplex M1 can colonize the roots of maize. The P. simplex M1 inoculant plant increased chlorophyll in leaves, stimulated root and leaf growth, increased the number of lateral roots and root dry weight, increased the length and width of the blades, and dry weight of the blades. The application of inoculants can significantly reduce the content of malondialdehyde (MDA) and increase the activity of plant antioxidant enzymes (Catalase (CAT), Superoxide Dismutase (SOD), and Peroxidase (POD)), which may thereby improve maize resistance to saline and alkaline stress. Conclusion: P. simplex M1 isolate belongs to plant growth-promoting bacteria by having high nitrogen concentration, indoleacetic acid (IAA), and siderophore, and reducing the content of ROS through the antioxidant system to alleviate salt alkali stress. This study presents the potential application of P. simplex M1 as a biological inoculant to promote plant growth and mitigate the saline and alkaline effects of maize and other crops.

Greenhouse gas emissions during alfalfa cultivation: How do soil management and crop fertilisation of preceding maize impact emissions?

ContextThe use of alfalfa in rotation with intensive crops is common practice to mitigate the physical and chemical issues arising from intensive farming practices. However, there is a dearth of studies on this practice. Given the current concern regarding climate change and the significant impact agriculture has on greenhouse gas (GHG) emissions, understanding the emissions associated with this practice, as well as the most suitable soil and crop management techniques for their mitigation, is of paramount importance. ObjectiveThe present study aimed to (i) quantify emissions of N2O, CO2 and CH4 in an alfalfa crop following a maize cropping scenario; (ii) to determine which tillage system generates the lowest GHG emissions, and; (iii) to determine how N fertilisation from a preceding intensive maize crop affects GHG emissions during alfalfa cropping period. MethodsA three-year field experiment (2019, 2020 and 2021) was conducted to assess the emissions of N2O, CO2 and CH4 from alfalfa cultivation following a three-year period of irrigated maize. Two soil management practices (no-tillage and conventional tillage) were implemented during both the maize cropping period and the alfalfa establishment. Additionally, the nitrogen (N) fertilisation rates applied to the preceding maize crop were included as a treatment (0, 200, and 400 kg N ha⁻¹, corresponding to zero, medium, and high fertilisation levels, respectively) in a randomized block design with two factors. ResultsEmissions of N2O in alfalfa ranged from 0.05 to 0.32 mg N2O-N m⁻² day⁻¹, being significantly higher only during first month of sampling in the treatments that had received fertilisation. CO2 emissions ranged from 1158 to 4258 mg CO2-C m⁻² day⁻¹. Year-average CH4 fluxes were −0.27 g C ha⁻¹ day⁻¹. The average total dry matter produced by alfalfa was 17700 kg ha⁻¹ year⁻¹, being higher for the no-tillage treatment, though significantly so only during first month of sampling. ConclusionsUnder Mediterranean conditions, the tillage system and mineral N fertilizer rates have a relative effect on greenhouse gas emissions during the alfalfa cropping period. Plots without N fertilization initially produced lower N2O emissions and higher total dry matter, resulting in the lowest scaled emissions. For the tillage treatment, no significant differences were found in emission dynamics, which may be due to the fact that alfalfa does not involve soil disturbance, leading to a homogenization of the treatments. However, the NT treatment showed lower scaled emissions due to higher yields in the first year. Therefore, alfalfa cultivation is characterized by low GHG emissions, high yields, and a notable capacity to mitigate the negative effects of previous intensive crops. SignificanceThis study provides data on GHG emissions during alfalfa cropping in the typical Maize-alfalfa crop rotation under Mediterranean irrigated systems, which is useful for new agricultural policies aimed at reducing pollution in the agricultural sector. Additionally, it demonstrates the capability of this crop to mitigate adverse agronomic and environmental conditions caused by preceding intensive farming practices.

Investigation of the impact of dual inoculations of arbuscular mycorrhizal fungi and plant growth-promoting rhizobacteria on drought tolerance of maize grown in a compost-amended field under Mediterranean conditions.

In the current context of rapid climate change, water scarcity and soil poverty are becoming increasingly alarming, leading to growing losses of 30-50% of global agricultural production. It is imperative to find environmentally-friendly approaches for improving plant tolerance to drastic conditions, particularly in arid and semi-arid Mediterranean regions. Biostimulants based on symbiotic microbes are emerging as effective strategies for improving tolerance and agricultural productivity. This study aims to evaluate the effects of single and double inoculation of arbuscular mycorrhizal fungi (My) and plant growth-promoting bacteria (Ba) on the growth, physiological and biochemical traits of maize crop grown in compost (Co) amended soil under two irrigation regimes: well-watered (WW: 100% of crop evapotranspiration [ETc]) and drought-stressed (DS: 50% ETc) using drip irrigation system. Reducing irrigation to 50% reduced shoot dry weight (SDW), root dry weight (RDW), 1,000-grains weight (TGW) and grain yield (Y). However, Ba alone increased SDW by 63%, while CoMyBa improved RDW, TGW and Y by 197, 43 and 175%, respectively compared with the control under DS conditions. Dual inoculation boosted root colonization intensity, normalized difference vegetation index (NDVI), total chlorophyll and leaf area of maize seedlings in compost-amended soil, compared to the controls. The application of Ba significantly reduced hydrogen peroxide and malondialdehyde by 46%, in maize seedlings grown in compost-amended soil, compared to the controls under DS. Our results indicated that My and Ba significantly boost the ability of maize to tolerate drought by improving water supply and physiology and stimulating the accumulation of organic and inorganic osmolytes, as well as improving the properties of soils such as cation exchange capacity particularly amended by Co. The dual inoculations were the most effective and represent an environmentally-friendly and relatively inexpensive approach to optimizing agricultural production and soil restoration programs in Mediterranean regions.

Remediation quantum of organic amendments to immobilize potentially toxic heavy metals in wastewater-contaminated soils through maize cultivation

Wastewater is considered a good reservoir of mineral elements that can be used for agriculture, aquaculture, and some other activities after adopting suitable measures. The gap between supply and demand for water is increasing exponentially because of the abrupt boost to the world’s population. This poses a threat to human life as it has reached alarming levels in some parts of the globe. Normally, wastewater consists of liquid waste produced by commercial or industrial sources for daily use, consumption, and production. It is time to refocus our attention on a kind of circulating water system by reusing municipal wastewater for agricultural purposes, particularly irrigation. The recycled or treated water would be used as an alternative to fresh water. In the current study, the impact of various organic amendments was studied to mitigate the toxic effects of pollutants present in wastewater by cultivating maize as a test crop. The present study comprised five treatments replicated four times with a randomized complete block design under field conditions. In this experiment, the treatments included T1 (treatment 1) = control (wastewater-polluted soil without the application of any amendment), T2 = farmyard manure (FYM) at 2.5 tons ha-1 (hectare-1), T3 = FYM at 5.0 tons ha-1, T4 = compost at 2.5 tons ha-1, and T5 = compost at 5.0 tons ha-1. The application of FYM at 5.0 tons ha-1 (T3) was recorded as being the most effective as the maximum improvement was observed in soil characteristics such as pH, electrical conductivity (EC), sodium adsorption ratio (SAR), and organic matter, and for T3, these were 7.33, 2.22 dS m-1, 8.16, and 0.94%, respectively. T3 remained most superior in reducing the concentration of heavy metals in the soil; for example, lead, cadmium, nickel, and arsenic for T3 were 8.64, 1.34, 10.44, and 2.25 mg kg-1 (milligrams per kg), respectively. Maximum fresh biomass (fodder yield) of 9.98 tons ha-1 was harvested when FYM was applied at 5.0 tons ha-1 to the soil compared to 6.2 tons ha-1 in the control plot. The highest contents of nitrogen (1.20%), phosphorus (0.41%), and potassium (3.97%) were observed in maize plants for T3. In maize plants (T3), the concentration of lead, cadmium, nickel, and arsenic was reduced to levels of 1.92, 0.23, 2.28, and 1.25 mg kg-1, respectively. Therefore, it can be concluded from the findings of the experiment that the application of FYM significantly reduced heavy metal concentrations and improved soil health, along with maize crop growth and productivity.

Enhancing pest management - Utilizing supplementary food spray to harness predatory insects against fall armyworm in maize crop of Vinh Phuc Province, Vietnam

The effect of supplementary food spray on the fall armyworm (Spodoptera frugiperda) and beneficial insects (predominantly predatory insects) was studied in commercial maize field experiments from 2020 to 2022. The food spray formulation was developed from local ingredients in Vietnam, both with and without neem extract. The sugar-based rice dough product attracted and sustained beneficial insects, significantly reducing fall armyworm populations. Compared to conventional insecticide treatments, the net margin achieved in plots treated with food spray was higher ($3,467) to $3,394 in the conventional insecticide-treated plots demonstrating its economic viability (1 AUD=17.28 VND). Our study observed an average predator-to-prey ratio of 9.2:1 per plant in the food-spray-treated plots, and that was effective in managing the fall armyworm throughout the season. We propose that this ratio can serve as a valuable parameter and decisionmaking tool in food spray-based Integrated Pest Management (IPM) programs against fall armyworm in maize fields. Therefore, we suggest that food sprays can be incorporated into IPM strategies to successfully manage fall armyworm infestation in maize crop.