Pigmented corn is a gramineae food of great biological, cultural and nutritional importance for many Latin American countries, with more than 250 breeds in the American continent. It confers a large number of health benefits due to its diverse and abundant bioactive compounds. In this narrative review we decided to organize the information on the nutrients, bioactive compounds and phytochemicals present in pigmented corn, as well as their effects on human health. Phenolic compounds and anthocyanins are some of the most studied and representative compounds in these grasses, with a wide range of health properties, mainly the reduction of prooxidant molecules. Carotenoids are a group of molecules belonging to the terpenic compounds, present in a large number of pigmented corn breeds, mainly the yellow ones, whose biological activity incorporates a wide spectrum. Bioactive peptides can be found in abundance in corn, having very diverse biological effects that include analgesic, opioid, antihypertensive, etc. activity. Other compounds with biological activity found in pigmented corn are resistant starches, some fatty acids, phytosterols, policosanols, phospholipids, ferulic acid and phlobaphenes, as well as a great variety of vitamins, elements, and fibers. This review aims to disseminate and integrate the existing knowledge on compounds with biological activity in pigmented corn, in order to promote their research, interest and use by scientists, nutrition professionals, physicians, industries and the general population.

The aims of study was to evaluate the effects of rates, sources and timing of nitrogen application under cover of transgenic corn yield cultivated in Amazon Biome. The experiments were conducted in Parauapebas city, State of Pará, Brazil, in two years (2016/2017 and 2017/2018). The experimental design was randomized blocks, in a 5x2x2 factorial scheme, consisting of five rates of N (0; 45; 90; 135; and 180 kg ha-1), two nitrogen sources (urea and ammonium sulfate) and two application times of N (phenological stages V4 and V8), with four replications. The factor N rates promoted adjustment of linear equation (leaf area index, mass of thousand grains, and yield) and quadratic equation (dry mass of leaf index). Nitrogen fertilization promoted significant increases in mass of thousand grains and yield, obtaining the best results with 180 kg ha-1 of N applied at V4 phenological stage. Based on results obtained in two years of corn cultivated under conditions of Amazon Biome, the application of N at V4 phenological stage at rates of 121 to 131.39 kg ha-1 of N showed the best results for vegetative growth, while 180 kg ha-1 of N, regardless of source used, urea or ammonium sulfate, promoted greater grain weight and greater yield.

Boron (B) toxicity is an important stress that negatively affects maize yield and quality production. The excessive B content in agricultural lands is a growing problem due to the increase in arid and semi-arid areas because of climate change. Recently, two Peruvian maize landraces, Sama and Pachía, were physiologically characterized based on their tolerance to B toxicity, the former being more tolerant to B excess than Pachía. However, many aspects regarding the molecular mechanisms of these two maize landraces against B toxicity are still unknown. In this study, a leaf proteomic analysis of Sama and Pachía was performed. Out of a total of 2793 proteins identified only 303 proteins were differentially accumulated. Functional analysis indicated that many of these proteins are involved in transcription and translation processes, amino acids metabolism, photosynthesis, carbohydrate metabolism, protein degradation, and protein stabilization and folding. Compared to Sama, Pachía had a higher number of differentially expressed proteins related to protein degradation, and transcription and translation processes under B toxicity conditions, which might reflect the greater protein damage caused by B toxicity in Pachía. Our results suggest that higher tolerance to B toxicity of Sama can be attributed to more stable photosynthesis that would avoid damage caused by stromal over-reduction under this stress condition.

The use of plant growth-promoting bacteria can be one option for mitigating the impact of abiotic constraints on different cropping systems in the tropical semi-arid region. The aim of this study was to evaluate growth, leaf gas exchange and yield in maize inoculated with Bacillus aryabhattai, and subjected to water and salt stress. The experiment followed a randomised block design, in a split plot arrangement, with six repetitions. The plots comprised two levels of electrical conductivity for the irrigation water (ECw): 0.3 dS m-1 and 3.0 dS m-1; the subplots consisted of three irrigation depths (ID1: 50%, ID2: 75%, and ID3: 100% of the crop evapotranspiration (ETc)); while the sub-subplots included the presence or absence of Bacillus aryabhattai inoculant. A water deficit of 50% of the ETc resulted in the principal negative effects on growth, reducing the leaf area and stem diameter. The use of Bacillus aryabhattai mitigated salt stress and promoted better leaf gas exchange by increasing the CO2 assimilation rate, stomatal conductance, and internal CO2 concentration. However, irrigation with brackish water (3.0 dS m-1) reduced the instantaneous water use efficiency of the maize. Inoculation partially reduced the effects of abiotic stress due to morpho-physiological traits, and increased yield potential under water deficit with no salt stress.

Using two infectious DNA clones originating from isolates obtained in Kenya, a genetic investigation of maize streak virus (MSV) pathogenicity was carried out. The susceptible Pioneer hybrid 3379 was used to investigate the virulence of kernels administered through vascular puncture inoculation. Mild [pMSV-KL (mild)] and severe [pMSV-Km(severe)] parental infectious MSV DNA clones were linked with considerable changes in the severity of chlorotic streaks and stunting of seedlings. Using restriction endonuclease fragments, chimeric clones were created from parental clones in order to investigate the genetic elements influencing these changes. Restrictions mapping was used to validate clone identities. For genomic portions encoding the replication initiator (Rep and RepA), movement (MP), and coat (CP) protein ORFs as well as for those containing non-coding long (LIR) and short intergenic regions (SIR), putative virulence determinants were discovered. Recombinant clones with intermediate symptoms included LIRs together with the first 189 nt of the Rep/RepA ORFs from the pMSV-Km (Severe) and pMSV-KL (Mild) ORFs. Symptoms identical to those of parental clones were produced by complementary substitution of the Rep/RepA ORF. When compared to pMSV-Km (Severe), the recombinant clone having MP, CP, and SIR genome sequences from pMSV-KL(Mild) and LIR, Rep, and RepA genome sequences from pMSV-Km (Severe) displayed much more severe symptoms and accumulated greater concentrations. The reciprocal clone, in contrast, displayed much milder signs and virus titers than pMSV-KL(Mild). The level of leaf chlorosis and plant stunting were linked with viral accumulation. These findings are consistent with the idea that MSV virulence is a polymorphic feature involving complementary sense genes (LIR and SIR) and the virion.

Spodoptera frugiperda is a widely distributed insect pest that causes major economic losses in various crops, particularly maize. On the other hand, Beauveria bassiana is an entomopathogenic fungus that establishes symbiotic associations with many plants and contributes to tolerance against biotic and abiotic stresses. In the present work, under field conditions, 1x106 (first trial) and 1x10⁸ (second trial) of B. bassiana (GHA strain) blastospores were used for corn’s seed inoculation. In the first field trial, a higher number of larvae were present in the negative control plants in comparison with those in B. bassiana-treated plants. No larvae were found in negative control and B. bassiana-treated plants in the second field trial. In further laboratory experiments, the effects of the B. bassiana strains GHA, in addition to a native strain (PTG4) also delivered via seed treatment in maize seedlings, on S. frugiperda growth, development, and mortality were evaluated. 1x10⁶ B. bassiana blastospores were used to inoculate maize seeds, which were germinated and grown to seedlings under growth chamber conditions. Third-instar S. frugiperda larvae were allowed to feed on B. bassiana-treated and -untreated (negative control) seedlings until reaching 6th instar and transferred to artificial diet until reaching adult stage. Results showed that larvae feeding on B. bassiana strain PTG4 prolonged their larval stage. Furthermore, feeding with plants treated with B. bassiana strains yielded fewer S. frugiperda male moths and the female moths emerged with altered wings, compared with the untreated control. In conclusion, seed treatment with B. bassiana in maize reduced S. frugiperda infestation of maize plants in field trials. Besides S. frugiperda development was affected in laboratory trials.

Multi-cropping can solve the energy and GHG balance problems, but the emergence, development and productivity of such mixed crops are at risk due to increasing drought periods. For this reason, single maize crops with inter-row mellowing and weed-mulching practices were compared with faba bean, crimson and Persian clover, and alfalfa intercropped maize cultivations. Tests were performed at the Experimental Station of Vytautas Magnus University, Lithuania. Results showed that by the 30% higher energy inputs were calculated in technologies with intercropped crimson, Persian clover, and alfalfa than in monocropped maize. Single maize crops produced by the 23-40% higher biomass yields compare to clover and alfalfa intercropped maize because, due to the drought periods, intercrops weakly sprouted and developed. Lower harvests reduced the energy output by up to 38%, energy efficiency ratio - by up to 2.5 times and net energy - by up to 42%. All tested technologies were environmentally friendly and similar according to the CO2 equivalent. Long-term drought periods during vegetative season due to climate change make us think about the improvement of intercropping technologies. Sowing intercrops at the same time with maize could solve the problem of its germination but highlight the problem of abundant weed spread. Therefore, this takes us to another sphere of agrotechnologies - the effective non-chemical weed control.

Several traps are recommended for monitoring corn earworm, Helicoverpa zea (Boddie), an important pest of field, vegetable and fruit crops in the U.S. These traps, which are meant to capture H. zea in many cases end up capturing other insects. Helicoverpa zea has recently been found feeding on different seeds and dual-type (seed and fiber) hemp, Cannabis sativa L. (Rosales: Cannabaceae) causing serious damage. Limited work has been done on developing integrated pest management (IPM) for H. zea industrial hemp in Missouri. We evaluated the attractiveness of different traps with the aim of developing a monitoring system for the adult male H. zea in industrial hemp fields in two Missouri locations In addition, we recorded other non-target insects in the traps to determine trap selectivity. Commercially available green, clear, tricolor bucket traps Heliothis Scentry and Scentry Delta 1X traps baited with H. zea sex pheromones were evaluated in 2021 and 2022. Tricolor traps captured significantly more adult male H. zea than the other traps in both years. Non-target insects, mainly Xylocopa virginica (L.) (Hymenoptera: Apidae), Bombus spp (Hymenoptera: Apidae), and Apis mellifera L. (Hymenoptera: Apidae) were also captured. The tricolor trap captured the most bees. The presence of non-target species highlights the risk of using tricolor traps as a monitoring tool. This data provides information for planning the monitoring of corn earworm in industrial hemp farms in Missouri.

Corn tassel is a by-product from hybrid corn seed production and a new source of phytochemicals including compounds with antioxidant activity. Four tassel development stages were evaluated in eight commercial corn varieties. Corn varieties and tassel developmental stages showed significant variations (P0.01) for all parameters. Total phenolic content and antioxidant activity were highest in field corn. KGW1, a purple waxy variety, had the highest anthocyanin content and carotenoid content at tassel development stages at 50% and 75% of pollen shed, whereas the tassel developmental stages at the 1st day of pollen shed and 50% of pollen shed had the highest of anthocyanin yield and carotenoid yield. The most suitable time for tassel harvest should be between the 1st day of pollen shed to 50% of pollen shed. Phytochemicals and antioxidants that are extracted from corn tassel can be used as a functional food supplement, natural pharmaceuticals and cosmetic products.

Balanced nitrogen (N) and phosphorus (P) rates coupling with rational fertilization methodology could promote crop N accumulation, N use efficiency and yield production, particularly in semi-arid and arid regions. To test these characteristics, a two-year (2018 and 2019) pot experiment was therefore performed by growing summer maize in a rain-proof glass greenhouse, under 9 combined N (112, 150 and 187 kg ha-1, urea) and P (45, 60, 75 kg ha-1, calcium superphosphate) rates and three contrasting fertilizer placements. The fertilizers were placed by broadcast on soil surface (Broadcast), side band on 4 cm strip soil surface within 7 cm from sowing line (Side band) and deep band on 4 cm strip below 7 cm soil depth within 7 cm from sowing line (Deep band). Results from three maize growth stages (eight-leaf, 45 days after sowing, DAS; tasseling, 60 DAS; and harvest, 115 DAS) showed that leaf, stem, root N accumulation and total soil N were significantly increased under Deep band than under both Side band and Broadcast at N150P60, N187P60, N150P75 and N187P75, but not at N112P45, N150P45, N187P45, N112P60 and N112P75. Significantly greater leaf, stem, and root N accumulations were also displayed at N150 and N187 than at N112 for the same P60 or P75 under Deep band at 60 DAS and 115 DAS, while were for leaf and stem N accumulations at P75 and P60 than at P45 for the same N150 under Deep band at 45 DAS, 60 DAS and 115 DAS. Significantly greater agronomy N use efficiency, partial factor productivity and N use efficiency exhibited under Deep band than under Side band and Broadcast at N150P75 and N187P75, but at N150P60 and N187P60 for NUE only. In addition, leaf, stem, seed, root N concentrations positively correlated with their own N accumulations or soil N concentration at tasseling and harvest stages. Our results demonstrate that a synchronized N150P60, N187P60, N150P75 or N187P75 fertilization rate with Deep band placement can improve soil N availability and root N uptake, and hereby greater aboveground N accumulation, N use efficiency and yield production of maize particularly practical for small-holder farmers globally.

The potential yield of annual crops is affected by management practices and water and energy availabilities throughout the crop season. The current work aimed to assess the effects of plant population and soil covering on yield components of maize. Field experiments were carried out during 2014-15 and 2015-16 growing seasons at areas grown with oat straw, voluntary plants and bare soil, considering five different plant populations (40,000, 60,000, 80,000, 100,000 and 120,000 plants ha-1) and three sowing dates (15 Sep., 30 Oct., 15 Dec.) for the hybrid P30F53YH in Ponta Grossa, State of Parana, Brazil. Non-impacts of soil covering or plant population on plant height at the flowering phenological stage were observed. Significant effects of soil covering on crop physiological and yield components responses throughout the 2014-15 season were detected. Influence of plant populations on yield components was evidenced, suggesting that from 80,000 plants ha-1 the P30F53YH hybrid performs a compensatory effect among assessed yield components in such a way as to not compromise productivity insofar as plant population increases up to 120,000 plants ha-1. It was noticed a positive trend of yield components and crop final yield as a function of plant density increments.

There is a large body of research on determining the impact of field variability of soil on crop yields. In contrast, site-specific information about crop responses to agronomic treatments is less frequent. On-Farm Precision Experimentation (OFPE) brings important information to understand the spatial variation of crop response to agronomic practices and thus to improve agronomic decisions. The objective of this work was to investigate the spatial variability of corn yield responses to nitrogen and seed rates using OFPE in four fields in the US Midwest. Geographically weighted regression was applied to generate local regression coefficients, which were used to delineate response zones in each field. The results showed the existence of great potential to adjust the rates of these inputs according to the response of each zone identified by the proposed method. The results of this study can be applied to reevaluate expectations on variable rate prescriptions guided largely by soil and variability.

Members of the insect ATP binding cassette transporter subfamily C2 (ABCC2) in several moth species are known as receptors for the Cry1Ac insecticidal protein from Bacillus thuringiensis (Bt). Mutations that abolish the functional domains of ABCC2 are known to cause resistance to Cry1Ac, although the reported levels of resistance vary widely depending on insect species. In this study, the function of the ABCC2 gene as putative Cry1Ac receptor in Helicoverpa zea, a major pest of over 300 crops, was evaluated using CRISPR/Cas9 to progressively eliminate different functional ABCC2 domains. Results from bioassays with edited insect lines support that muta-tions in ABCC2 was associated with Cry1Ac resistance ratios (RR) ranging from 7.3- to 39.8-fold. No significant differences in susceptibility to Cry1Ac were detected between H. zea with partial or complete ABCC2 knockout, although highest levels of tolerance were observed when knocking out half of ABCC2. Based on >500-1,000-fold RRs reported in similar studies for closely related moth species, the low RRs observed in H. zea knockouts support that ABCC2 is not a major Cry1Ac receptor in this insect.

Invasion ecology has a long tradition of searching for traits distinguishing alien invasive and non-invasive plants. Surprisingly, this approach has been so far poorly used to understand why some arable weeds are abundant and widespread while others are rare and narrowly distributed. In the present study, we focused on the characteristics of successful weeds occurring in maize fields, one of the most import crop worldwide. Two national weed surveys conducted in France were used to identify increasing and decreasing species based on 175 and 484 surveyed fields in the 1970s and the 2000s, respectively. Weed trait values related to regional frequency, local abundance and specialization to maize were identified with Phylogenetic Generalized Least-Squares (PGLS). We found a positive relationship between regional frequency and local abundance, i.e. the most widespread weeds were also locally more abundant. We highlighted that weeds with the C4 photosynthetic pathway and summer emergence were more abundant, more frequent and more specialized to maize crops. More generally, we highlighted two successful strategies: on the one hand, traits related to a general weediness syndrome with rapid resource acquisition (high SLA and Ellenberg-N) and high colonization capacity (seed longevity, fecundity and wind dispersal), on the other hand, traits related to specific adaptation to spring cultivation (thermophilous species with summer emergence, late flowering and C4 photosynthetic pathway). Deviations from the abundancy-frequency relationships also indicated that species of the Panicoideae sub-family, species with Triazine-resistant populations and neophyte species were more abundant than expected by their regional frequency. To some extent, it is therefore possible to predict which species can be troublesome in maize crops and use this information in weed risk assessment tools to prevent new introductions or favor early detection and eradication. This study showed how tools developed in functional and macro-ecology can be used to improve our understanding of weed ecology and to develop more preventive management strategies.

The targeted application of plant growth promoting rhizobacteria (PGPR) provides the key for a future sustainable agriculture with reduced pesticide application. PGPR interaction with the indigenous microbiota is poorly understood but essential to develop reliable applications. Therefore, Stenotrophomonas rhizophila SPA-P69 was applied as seed coating and in combination with a fungicide based on the active ingredients fludioxonil, metalaxyl-M, captan and ziram. Plant performance and rhizosphere composition of treated and non-treated maize plants of two field trials were analyzed. Plant health was significantly increased by treatment; however overall corn yield was not changed. By applying high-throughput amplicon sequencing of the 16S rRNA and the ITS genes, the bacterial and fungal changes in the rhizosphere due to different treatments were determined. Despite treatments had a significant impact on the rhizosphere microbiota (9- 12%), the field site was identified as main driver (27- 37%). Soil microbiota composition from each site was significantly different, which explains the site-specific effects. In this study we were able to show first indications how PGPR treatments increase plant health via microbiome shifts in a site-specific manner. This way first steps towards a detailed understanding of PGPRs and developments of consistently efficient applications in diverse environments are set.

Agriculture uses a lot of fuel, fertilizers, pesticides and other substances, while emitting large amounts of GHGs. It is important to optimize these inputs and outputs. One such way is increas-ing crop biodiversity. For this reason, single crops and mixtures of maize, hemp and faba bean as binary and ternary crops were investigated at the Experimental Station of Vytautas Magnus Uni-versity, Lithuania. Results showed that consumption of diesel fuel was by the 31-46% higher than in single and 22-35% higher than in binary cultivations was found in a ternary crop. This influenced on the highest energy input or near twice higher than in maize and hemp single crops and maize+hemp binary crop, but similar with binary crops with faba bean. Despite this, the productivity of the trinary crop and, at the same time, the energy output were 2-5 times higher than in other treat-ments. This compensated for higher energy inputs and the energy efficiency ratio. In ternary crop, energy productivity was from 1.1 to 2.8 times higher and net energy was by 1.9-5.3 times higher than in other tested cultivations. The highest total GHG emissions were obtained in binary maize+hemp and maize+faba bean cultivations (1729.84 and 2067.33 CO2eq ha-1). Ternary cultiva-tion with the highest energy inputs initiated average GHG emission - 1541.90 kg ha-1 CO2eq. For higher efficiency, ternary crop could be sown and harvested in one machine pass. Faba beans should be included in the ter-nary crops, as their biomass takes a significant part of the total biomass produced. We recommend to review the inter-cropped faba bean seeding rates as faba bean seeds have a high energy input equivalent.

The genus Fusarium includes several agronomically important and toxin-producing species, that are worldwide distributed and can cause a wide range of diseases. Crown and stalk rots and grain infections are among the most severe symptoms that Fusarium spp. can cause on maize. The disease development usually occurs during germination, but it may also affect the later phases of plant growth. The purpose of this study was to investigate the diversity and the patho-genicity of 41 isolates recovered from symptomatic seedlings collected in Northern Italy, and from seeds with five different geographical origins during 2019 and 2020. The pathogenicity was tested and confirmed on 23 isolates causing rotting on maize seedlings. A multi-locus phylogeny analysis, based on four genomic loci (tef1-α, rpb2, calm and tub2), was performed for 23 repre-sentative isolates. Representative isolates were identified as species belonging to three species complexes (SC). Fusarium verticillioides and F. annulatum in the F. fujikuroi SC. Fusarium commune was identified in the F. nisikadoi SC, and three different lineages were found in the Fusarium ox-ysporum SC. This study reports F. annulatum, and two lineages of the Fusarium oxysporum SC as maize pathogens for the first time in Italy.

In plants, water flows are the major driving force behind the growth and play a crucial role in the life cycle. To study hydrodynamics, methods based on tracking small particles inside water flows occupy a special place. Due to these tools, it is possible to get information about the dynamics of the spatial distribution of the fluxes characteristics. In this paper, using contrast-enhanced MRI, we have shown that gadolinium chelate, used as an MRI contrast agent, marks the structural characteristics of xylem bundles of maize stem nodes and internodes. Supplementing MRI data, a high-precision visualization of xylem vessels by laser scanning microscopy was used to reveal structural and dimensional characteristics of the stem vascular system. In addition, we proposed the concept of using the prototype "Y-type xylem vascular bundles" as a model of the elementary connection of vessels within the vascular system. A Reynolds number can match the microchannel model with the real xylem vessels.