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The objective of this study was to evaluate the intake and digestibility of nutrients, production and composition of milk, and water intake of lactating dairy cows fed standard diets in which ground corn (C) was replaced by up to 100% in the diet by cactus pear (CP). Eight Girolando cows (½ Gyr x ½ Holstein), 3rd calf multiparous, with 60 to 80 days of lactation and an average weight of 450.0 ± 30.0 kg, were randomly distributed in a double Latin square (4 × 4). Four experimental diets were evaluated: (100% C + 0% CP), (66.6% C + 33.3% CP), (33.3% C + 66.6% CP), and (0% C + 100% CP). There was a difference (P < 0.05) in the intake of CP and EE (kg.day- 1), with a quadratic effect and a linear reduction, respectively, with substitution. The maximum CP intake of 3.05 kg.day- 1 was found at 46.07% and EE intake fell by 3.81 g for each percentage unit of cactus pear added to the diet. There was a quadratic difference (P < 0.05) for DM intake in %BW and g.kg BW0,75, with maximum values of 3.97%BW and 186.8 g.kg BW0,75 with the substitution of 54.83 and 53.17%, respectively. There was a quadratic effect (P < 0.05) for the intake of NDF in %BW, with the maximum intake of 1.3% at the 74.69% substitution level. There was a linear reduction (P < 0.05) in the digestibility of DM, NDF, and TDN, and for the other nutrients there was no substitution effect (P > 0.05). There was no difference (P > 0.05) in milk production and composition. There was a linear reduction (P < 0.05) in water intake. Cactus pear can be used in a promising way to replace ground corn up to 100% in the diet of lactating dairy cows.

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The tropical maize breeding for low-P tolerance and good performance under low-P stress environments can be achieved through selection based on root morphology traits at seedling stage. Here, we assessed the genotypic variation and genetic diversity of a panel of 151 tropical maize inbred lines for root and shoot seedling traits, investigated the relationship among traits and selected a set of promising inbred lines for low-P tolerance and performance. We evaluated the inbred lines at seedling stage in a greenhouse experiment under two conditions: applied P (AP) and non-applied P (NAP). A mixed model approach was used to estimate variance components and predict the genotypic values of each inbred line. The genetic diversity among inbred lines based on root and shoot traits was assessed, and correlations were estimated between tested traits under AP and NAP. Our panel of inbred lines showed huge genetic variability for all traits and presented large genetic diversity under both P conditions. Variance components due to the inbred line × P condition interaction were also highly significant (P < 0.01) for all traits. Root dry weight (RDW) was positively associated with stalk dimeter (SD), shoot dry weight (SDW) and root length, volume, and area under both P conditions. Also, the SD and SDW were associated with most root traits under AP. Based on low-P tolerance and performance indices, we selected a set of top 20 inbred lines to be used in our maize breeding program. We therefore concluded that there is a significant genetic diversity in the tropical maize inbred lines which have the genetic potential to be use in association mapping studies and also to develop improved low-P tolerant and P-efficient hybrids and maize breeding populations for low-P stress environments.

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Phosphorus (P) is an essential macronutrient for maize (Zea mays L.) growth and development. Therefore, generating cultivars with upgraded P use efficiency (PUE) represents one of the main strategies to reduce the global agriculture dependence on phosphate fertilizers. In this work, genome-wide association studies (GWAS) were performed to detect quantitative trait nucleotide (QTN) and potential PUE-related candidate genes and associated traits in greenhouse and field trials under contrasting P conditions. The PUE and other agronomy traits of 132 maize inbred lines were assessed in low and normal P supply through the greenhouse and field experiments and Multi-locus GWAS was used to map the associated QTNs. Wide genetic variability was observed among the maize inbred lines under low and normal P supply. In addition, we confirm the complex and quantitative nature of PUE. A total of 306 QTNs were associated with the 24 traits evaluated using different multi-locus GWAS methods. A total of 186 potential candidate genes were identified, mainly involved with transcription regulator, transporter, and transference activity. Further studies are still needed to elucidate the functions and relevance of these genes regarding PUE. Nevertheless, pyramiding the favorable alleles pinpointed in the present study can be considered an efficient strategy for molecular improvement to increase maize PUE.

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Cadmium (Cd) is a heavy metal that is highly toxic to plants and animals and can accumulate in the environment as a result of industrial activities and agricultural application of some types of phosphate fertilizer. This study aimed to assess the role of sodium nitroprusside (SNP), as a source of nitric oxide (NO) in alleviating Cd stress in maize plants. Maize plants were kept in soil saturated with 40%-strength nutrient solution in a greenhouse, and cadmium nitrate, Cd(NO3)2, was applied at different concentrations, (0, 10, and 50 µM). Sodium nitroprusside, [Fe(CN)5NO]·2H2O, at concentrations of 0.05, 0.1, and 0.2 µM. Growth, leaf gas exchange, and leaf anatomy analyses were performed. The experimental design was completely randomized in a 3 × 3 factorial arrangement with five replicates. The highest concentrations of Cd and SNP reduced the total dry mass and leaf and stem dry mass but increased the allocation of biomass to the roots and stem, but the leaf allocation did not change. The application of Cd and SNP promoted an increase in gas exchange and leaf area, in addition to an increase in leaf tissue thickness and stomatal density. The presence of SNP at low concentrations reduces the toxicity of Cd, but at high concentrations, this compound can generate negative effects and even toxicity in maize plants.

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Introduction: The fungus Fusarium verticillioides significantly threatens maize crops in tropical soils. In light of this, biological control has emerged as a promising strategy to reduce fungicide costs and environmental risks. In this study, we aimed to test the antifungal activity of cell-free supernatant (CFS) from three Bacillus velezensis (CT02, IM14, and LIS05) and one Paenibacillus ottowii (LIS04) against F. verticillioides, thereby contributing to the development of effective biocontrol measures. Methods: The research employed a comprehensive approach. The antifungal activity of the bacterial strains was tested using cell-free supernatant (CFS) from three Bacillus velezensis (CT02, IM14, and LIS05) and one Paenibacillus ottowii (LIS04). The UPLC-MS evaluated the CFS to identify the main bioactive molecules involved in the inhibitory effect on F. verticillioides. Scanning electron microscopy (SEM) was used to assess the impact of CFS on spores and hyphae, and genome sequencing was conducted to identify the genes involved in biological control. These robust methodologies ensure the reliability and validate our findings. Results: The CFS of the four strains demonstrated significant inhibition of fungal growth. The UPLC-MS analysis revealed the presence of lipopeptides with antifungal activity, including surfactin and fengycins A and B expressed by the three strains of Bacillus velezensis and iturin A expressed by strains LIS05 and IM14. For Paenibacillus ottowii, fusaricidins, ABCDE, and five previously unreported lipopeptides were detected. Scanning electron microscopy (SEM) showed that treatments with CFS led to significant distortion and breakage of the F. verticillioides hyphae, in addition to the formation of cavities in the membrane. Genome mining confirmed the presence of genes coding for the lipopeptides identified by UPLC-MS, including the gene for iturin in CTO2. Genomic sequencing revealed that CT02, IM14, and LIS05 belong to different strains of Bacillus velezensis, and LIS04 belongs to Paenibacillus ottowii, a species recently described. Discussion: The four bacterial strains, including three novel strains identified as Bacillus velezensis and one as the recently described species Paenibacillus ottowii, demonstrate significant potential as biocontrol agents for managing fungal disease. This finding underscores the novelty and potential impact of our research.

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Maize (Zea mays ssp. mays) diverged from one of its wild relatives, the teosinte Zea mays ssp. parviglumis, in the lowlands of southwest Mexico approximately 9000 years ago. Following this divergence, maize rapidly expanded throughout the Americas, becoming a staple food. This dispersal was accompanied by significant demographic and selective changes, leading to the development of numerous local varieties with a complex evolutionary history that remains incompletely understood. In recent years, genomic advances have challenged traditional models of maize domestication and spread to South America. At least three distinct genetic lineages associated with different migratory waves have been described: ancestral Andean, ancestral Lowland, and Pan-American. Additionally, the significant role of the teosinte Zea mays ssp. mexicana, in the evolution of modern maize has been recently uncovered. Genomic studies have shed light into highland adaptation processes, revealing largely independent adaptation events in Meso- and South America. As new evidence emerges, the regional complexity underlying maize diversity and the need for comprehensive, multi-scale approaches become evident. In the face of climate change and evolving agricultural landscapes, the conservation of native maize in South America is of growing interest, with genomics serving as an invaluable tool for identifying and preserving the genetic variability of locally adapted germplasm.

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Biosurfactants are amphiphilic biomolecules with promising tensoative and emulsifying properties that find application in the most varied industrial sectors: environment, food, agriculture, petroleum, cosmetics, and hygiene. In the current work, a 23 full-factorial design was performed to evaluate the effect and interactions of pineapple peel and corncob as substrates for biosurfactant production by Bacillus subtilis LMA-ICF-PC 001. In a previous stage, an alkaline pretreatment was applied to corncob samples to extract the xylose-rich hydrolysate. The results indicated that pineapple peel extract and xylose-rich hydrolysate acted as partial glucose substitutes, minimizing production costs with exogenous substrates. Biosurfactant I (obtained at 8.11% pineapple peel extract, 8.11% xylose-rich hydrolysate from corncob, and 2.8109 g/L glucose) exhibited a significant surface tension reduction (52.37%) and a promising bioremediation potential (87.36%). On the other hand, biosurfactant III (obtained at 8.11% pineapple peel extract, 31.89% xylose-rich hydrolysate from corncob, and 2.8109 g/L glucose) exhibited the maximum emulsification index in engine oil (69.60%), the lowest critical micellar concentration (68 mg/L), and the highest biosurfactant production (5.59 g/L). These findings demonstrated that using pineapple peel extract and xylose-rich hydrolysate from corncob effectively supports biosurfactant synthesis by B. subtilis, reinforcing how agro-industrial wastes can substitute traditional carbon sources, contributing to cost reduction and environmental sustainability.

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Bacteria can solubilize phosphorus (P) through the secretion of low-molecular-weight organic acids and acidification. However, the genes involved in the production of these organic acids are poorly understood. The objectives of this study were to verify the calcium phosphate solubilization and the production of low-molecular-weight organic acids by diverse genera of phosphate solubilizing bacterial strains (PSBS); to identify the genes related to the synthesis of the organic acids in the genomes of these strains and; to evaluate growth and nutrient accumulation of maize plants inoculated with PSBS and fertilized with Bayóvar rock phosphate. Genomic DNA was extracted for strain identification and annotation of genes related to the organic acids production. A greenhouse experiment was performed with five strains plus 150 mg dm- 3 P2O5 as Bayóvar rock phosphate (BRP) to assess phosphate solubilization contribution to maize growth and nutrition. Paraburkholderia fungorum UFLA 04-21 and Pseudomonas anuradhapurensis UFPI B5-8A solubilized over 60% of Ca phosphate and produced high amounts of citric/maleic and gluconic acids in vitro, respectively. Eleven organic acids were identified in total, although not all strains produced all acids. Besides, enzymes related to the organic acids production were found in all bacterial genomes. Plants inoculated with strains UFPI B5-6 (Enterobacter bugandensis), UFPI B5-8A, and UFLA 03-10 (Paenibacillus peoriae) accumulated more biomass than the plants fertilized with BRP only. Strains UFLA 03-10 and UFPI B5-8A increased the accumulation of most macronutrients, including P. Collectively, the results show that PSBS can increase maize growth and nutrient accumulation based on Bayóvar rock phosphate fertilization.

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Maize is one of the most important crops cultivated worldwide, whose production can be affected by the presence of several pathogens. Fusarium verticillioides and Fusarium graminearum are the most predominant pathogens affecting maize ears. However, few studies have been focused on studying the interaction between both pathogens in field conditions. For this reason, the aim of the present work was to evaluate the interaction between F. graminearum and F. verticillioides in different genotypes of maize under field conditions. Field experiments were carried out during two growing seasons in Azul, Argentina, including 12 commercial hybrids of maize, which were inoculated with F. graminearum, F. verticillioides, and a mixture of both pathogens. Phenotypic traits (plant height, plant diameter, tiller and cob number, and radiation interception), disease evaluation, and mycotoxin contamination were analyzed. The results showed significant differences between genotypes in disease severity (DS) for both years. In general terms, higher values of DS were reported in 2020 (21.70% ± 0.40) than in 2021 (16.50% ± 0.20). Different climatic conditions registered along the assay, especially precipitations and relative humidity, could be responsible for the differences observed over the years. Moreover, no significant correlations were found regarding DS and mycotoxin contamination for each genotype. For these reasons, an automatic correspondence between DS and mycotoxin contamination could lead to wrong agronomic decisions. The present study points out novel information regarding plant-pathogen interaction (maize-F. verticillioides/F. graminearum) under field conditions that could be useful for future maize breeding programmes.

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With the growing demand for sustainable and safe agricultural practices, plant compounds emerge as a solution for biological activities. Here, we evaluated the potential of using Morinda citrifolia essential oil to induce plant resistance and to control phytopathogens (Curvularia lunata) and insect pests (Daubulus maidis). We conducted a chromatographic analysis to unveil the essential oil components. We also quantified the activity levels of antioxidant enzymes and chitinase for resistance induction. The antifungal action was evaluated through disease progression and the inhibition of mycelial growth in addition to in silico studies that made it possible to predict the interaction site between the fungal protein and the compounds. We assessed the toxicity and repellent actions towards the D. maidis. Octanoic acid (58.43%) was identified as the essential oil major compound. Preventive treatment with essential oil and octanoic acid (25.0 µL mL-1) increased not only the plant defense activities (i.e., the activity of the enzymes superoxide dismutase, catalase, phenol peroxidase, ascorbate peroxidase, and chitinase) but also controlled Curvularia leaf spot. The stable interactions between octanoic acid and tyrosine-tRNA ligase from C. lunata suggested protein synthesis inactivation. The essential oil inhibited 51.6% of mycelial growth, and this effect was increased to 75.9% with the addition of adjuvants (i.e., angico gum). The essential oil reduced 76% of the population of D. maidis adults and repelled 50% of the number of D. maidis after 48 h under field conditions. The repellency effect in the field reduced the population of D. maidis adults, transmitters of the stunting complex, by 50%. The results highlight the potential of M. citrifolia as a resistance activator, fungicide, insecticide, and an effective biorational alternative.

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Corn (Zea mays) is the most widely planted crop in the world. Dalbulus maidis (Hemiptera: Cicadellidae) is currently a primary corn pest. The starting point for the development of pest control decision-making systems is the determination of a conventional sampling plan. Therefore, this study aimed to determine a practical conventional sampling plan for D. maidis in corn crops. Insect density was evaluated in 28 commercial fields. Subsequently, D. maidis densities were sampled from fields ranging from 1 to 100 ha. Insect density conformed to a negative binomial distribution in 89.29% of the fields. The insect densities determined using the sampling plan had a low error rate (up to 15%). Sampling time and costs ranged from 2.06 to 39.45 min/ha and 0.09 to 1.81 USD/ha for fields of 1-100 ha, respectively. These results provide the first precise and representative conventional sampling plan for scouting D. maidis adults grown in corn fields. Therefore, the conventional sampling plan for D. maidis determined in this study is practical and can be incorporated into integrated pest management programs for corn crops owing to its representativeness, precision, speed, and low cost.

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Bacterial leaf streak caused by Xanthomonas vasicola pv. vasculorum (Xvv) is an emerging disease in several corn-producing regions around the world. In Brazil, there is a lack of information on the survival of this bacterium in soil and crop residues. Thus, the objective of this study was to determine the survival of Xvv in soil and also in infected corn crop residues under the humid subtropical climate of southern Brazil. The survival of Xvv in soil was initially investigated in sandy and clayey soils maintained at 20, 25 and 30 °C under controlled conditions. The survival of the bacterium under field conditions was studied in artificially infested clayey soil. The survival of Xvv in corn crop residues was investigated in infected residues maintained on the soil surface or buried in the soil at 20 cm deep. Under controlled conditions, regardless of the type of soil, the bacterium survived longer at 20 °C than at higher temperatures. The bacterium survived for 40 days in clayey soil kept at 20 °C and four days in sandy soil maintained at 30 °C. Under field conditions, the survival of Xvv in the soil was only for 48 h and in infected corn crop residues for up to 15 days in the samples maintained on the soil surface. In samples of infected corn residues buried in the soil, the bacterium was only detected at the time the experiment was set up. In general, the results obtained in this study revealed that Xvv survives for a short period of time in soil and in infected corn crop residues under humid subtropical conditions. Therefore, soil and corn residues may not be highly important sources of primary inoculum for the development of bacterial leaf streak on corn crops under these conditions.

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Water stress can lead to physiological and morphological damage, affecting the growth and development of popcorn. The objective of this study was to identify the yield potential of 43 popcorn lines derived from a Latin American germplasm collection, based on agronomic and physiological traits, under full irrigation (WW) and water deficit conditions (WS), aiming to select superior germplasm. The evaluated agronomic traits included the ear length and diameter, number of grains per row (NGR) and rows per ear (NRE), grain yield (GY), popping expansion (EC), volume of expanded popcorn per hectare (VP), grain length (GL), width, and thickness. The physiological traits included the chlorophyll, anthocyanin, and flavonoid content in the leaves. The genetic variability and distinct behavior among the lines for all the agronomic traits under WW and WS conditions were observed. When comparing the water conditions, line L292 had the highest mean for the GY, and line L688 had the highest mean for the EC, highlighting them as the most drought-tolerant lines. A water deficit reduced the leaf greenness but increased the anthocyanin content as an adaptive response. The GY trait showed positive correlations with the VP, NGR, and GL under both water conditions, making the latter useful for indirect selection and thus of great interest for plant breeding targeting the simultaneous improvement of these traits.

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Corn is the second most cultivated crop in Brazil, the number-one country in pesticide consumption. Chemical control of weeds is performed using herbicides such as S-metolachlor with pre- and post-emergence action and thus the toxicity of herbicides constitutes a matter of great concern. The present investigation aimed to examine the effects of an S-metolachlor-based herbicide on Lactuca sativa L. (lettuce) and Zea mays L. (maize) utilizing various bioassays. The test solutions were prepared from commercial products containing the active ingredient. Seeds from the plant models were exposed in petri dishes and maintained under biochemical oxygen demand (BOD) at 24°C. Distilled water was negative and aluminium positive control. Macroscopic analyses (germination and growth) were conducted for both plant species, and microscopic analysis (cell cycle and chromosomal alterations) were performed for L. sativa root tip cells. Detrimental interference of S-metolachlor-based herbicide was noted with lettuce for all parameters tested reducing plant germination by over 50% and the germination speed by over 45% and showing a significant decrease in mitotic index, from 16.25% to 9,28% even on the lowest concentration tested. In maize, there was no significant interference in plant germination; however, speed of germination was significantly hampered, reaching a 51.22% reduction for the highest concentration tested. Data demonstrated that the herbicide was toxic as evidenced by its phyto- and cytotoxicity in L. sativa L. and Z. mays L.

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Zea mays L is a crucial crop for Brazil, ranking second in terms of production and sixth in terms of exports. In Brazil, the second season, or off-season, accounts for 80 % of the overall maize output, which primarily occurs after the soybean main season. A maize yield forecast model for the off-season was developed and implemented throughout Brazilian territory due to its importance to the country's economy and food security. The model was built using multiple linear regressions that connected outputs simulated from a land surface model used in large-scale analysis for agriculture (JULES-crop), to agrometeorological indicators. The application of the developed model occurred every 10 days from the sowing until the maturation. A comparison of the forecasting model was verified with the official off-season maize yields for the years 2003-2016. Agrometeorological indicators during the reproductive phase accounted for 60 % of the interannual variability in maize production. When outputs simulated by JULES-crop were included, the forecasting model achieved Nash-Sutcliffe modeling efficiency (EF) of 0.77 in the maturation and EF = 0.72 in the filling-grain stage, suggesting that this approach can generate useful predictions for final maize yield beginning on the 80th day of the cycle. Outputs of JULES crop enhanced modeling performance during the vegetative stage, reducing the standard deviation error in prediction from 0.59 to 0.49 Mg ha-1.

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Maize tortilla is the best-recognized food product of Mexican gastronomy. Artisanal maize tortillas (AMT) are prepared with native maize varieties and a traditional process. The aims of this study were to identify sensory attributes, texture, and color in AMT that allow them to be differentiated from commercial tortillas, and to determine the chemical and mineral composition of both types of tortillas. Six landraces related to four Mexican maize races were used. Two commercial tortillas were included as references (tortillería and supermarket). Tortillas were subjected to sensory analysis by the modified Flash technique, texture and color were measured objectively and chemical and mineral analysis of all tortillas were evaluated. Lime taste and lime smell attributes were relevant to differentiate AMT from commercial tortillas; aftertaste and fracturability attributes were highly associated to supermarket tortillas. The fracturability attribute of tortillas is consider undesirable for taco preparation. Five of the six AMT were characterized by the presence of a layer, a characteristic that is associated with traditional tortilla made by Mexican consumer. Regarding chemical composition, supermarket tortillas exhibited the highest dietary fiber content (17.09%), but showed 30% more Na than AMT, with the exception of tortillas from Purepecha native variety. Besides, supermarket tortilla had 48.9% less Ca than AMT. The sensory attributes relevant to differentiate native maize tortillas from the commercial maize tortilla references were appearance, smell, and taste, while textural and color attributes played a lesser role.

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The African planthopper Leptodelphax maculigera (Hemiptera: Delphacidae) has been recently reported in many places in Brazil in association with maize. Its occurrence in maize production fields in Brazil has brought concerns to the corn production chain regarding the possibility of this planthopper to be a vector for maize bushy stunt phytoplasma (MBSP), corn stunt spiroplasma (Spiroplasma kunkelii), maize rayado fino virus (MRFV), and maize striate mosaic virus (MSMV). The phytoplasma and spiroplasma, which are bacteria belonging to the class Mollicutes, and the two viruses are associated with the corn stunt disease complex. Given the presence of the African planthopper species and the corn stunt complex in Brazil, we further investigated the abundance of this planthopper species in the State of Santa Catarina, Brazil, and whether the planthopper can carry the four pathogens. We inspected 12 maize production fields in different municipalities in the state for 20 weeks, using two yellow sticky traps for each maize field. The sticky traps were replaced weekly. A total of 130 specimens of L. maculigera were captured, with a great discrepancy in quantity among locations and weeks. We detected the mollicute MBSP and the viruses MRFV and MSMV in L. maculigera, whereas S. kunkelii was absent in the assessed African planthopper samples. The molecular detection of the phytoplasma and the viruses in field-collected African planthoppers is strong evidence that this insect species has the ability to acquire those pathogens through feeding from the phloem of diseased maize plants. Nonetheless, transmission capacity needs to be experimentally proven to assert L. maculigera as a vector for the corn-stunting pathogens.

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Pigmented corn is a gramineae food of great biological, cultural and nutritional importance for many Latin American countries, with more than 250 breeds on 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 pro-oxidant 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 and antihypertensive activities. 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.

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The interactions between plants, beneficial bacteria and their environment are profoundly shaped by various environmental factors, including light, temperature, water availability, and soil quality. Despite efforts to elucidate the molecular mechanisms involved in the association between plants and beneficial bacteria, like Plant Growth-Promoting Bacteria (PGPB), with many studies focusing on the transcriptional reprogramming in the plant, there is no report on the modulation of genetic controls from both plant and associated bacteria standpoints, in response to environment. The main goal of this study was to investigate the relationship between plant-bacteria-environment signaling, using as a model maize plants inoculated with H. seropedicae ZAE94 and cultivated with different doses of N (0.3 and 3 mM). For this purpose, we performed rRNA-depleted RNA-seq to determine the global gene expression of both maize roots and associated H. seropedicae ZAE94. Our results revealed a differential modulation of maize nitrogen metabolism, phytohormone and cell wall responses when associated with H. seropedicae ZAE94 at different N concentrations. In parallel, a modulation of the bacterial metabolism could be observed, by regulating genes involved in transport, secretion system, cell mobility, oxidoreductases, and chemotaxis, when bacteria were associated with maize roots and cultivated at different doses of N. The molecular and phenotypic data of maize plantlets suggested that different doses of N fertilization differentially regulated the beneficial effects of bacterial inoculation, as higher doses (3 mM) favored shoot elongation and lower doses (0.3 mM) favored increase in plant biomass. Our results provide a valuable integrated overview of differentially expressed genes in both maize and associated H. seropedicae ZAE94 in response to different N availability, revealing new insights into pathways involved in grass-PGPB associations.

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This study aimed to assess the impact of adding forage cactus as an additive to the production of corn silage without the cob on the performance of feedlot sheep and subsequent silage losses. The experimental design was completely randomized, consisting of three treatments: corn silage without cob; 0% = 100% corn plant without the cob; 10% = 90% corn plant without cob + 10% forage cactus; 20% = 80% corn plant without cob + 20% forage cactus. Significant effects were observed for dry matter intake (P = 0.0201), organic matter (P = 0.0152), ether extract (P = 0.0001), non-fiber carbohydrates (P = 0.0007). Notably, nutrient digestibility showed significant differences in organic matter (P = 0.0187), ether extract (P = 0.0095), neutral detergent fiber (P = 0.0005), non-fiber carbohydrates (P = 0.0001), and metabolizable energy (P = 0.0001). Performance variables, including total weight gain (P = 0.0148), average daily weight gain (P = 0.0148), feeding efficiency, and rumination efficiency of dry matter (P = 0.0113), also exhibited significant effects. Consequently, it is recommended to include 20% forage cactus in corn silage, which, based on natural matter, helps meet animals' water needs through feed. This inclusion is especially vital in semi-arid regions and aids in reducing silage losses during post-opening silo disposal.

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