Sorghum Bicolor Research Articles

In silico Analysis and Characterization of the F5H Gene Family in Sorghum bicolor and Its Role in Lignin Production

Ferulate 5-hydroxylase (F5H), a cytochrome P450-dependent monooxygenase, catalyzes the hydroxylation of coniferaldehyde, a crucial step in the formation of syringyl lignin monomer (S). However, evolutionary divergence, expression patterns under abiotic stress conditions (ABA, PEG and NaOH) and lignin content-related features of the F5H gene family in Sorghum bicolor have not been explored. This study envisaged mining of Sorghum genomic data leading to the identification of 61 SbF5H genes. Bioinformatics analysis revealed the phylogenetic evolutionary relations, gene structures, conserved motifs, physicochemical properties, and promoter cis-acting elements related to these genes and their encoded proteins. Based on the gene structural and phylogenetic features, these 61 SbF5Hs were grouped into 4 subclasses. The in silico expression analysis revealed higher accumulation of SbF5H1 transcripts in embryo and in root under stress conditions. Similarly, Other SbF5H genes have shown expression in stem and root, thus indicating SbF5H genes involvement in Sorghum lignin biosynthesis. By exploring into the functional aspects of the F5H gene, our study sought to shed light on its significance in influencing not only the chemical makeup of lignin but also the resultant plant phenotypes. This insight into the molecular mechanisms governing lignin biosynthesis can have implications for bioenergy production and crop improvement.

Genetic variability, diversity and principal component analysis in B and R lines of rabi sorghum [Sorghum bicolor (L.) Moench

Hybrid technology is exploited in kharif (rainy) sorghum while the same is not the scenario in Rabi sorghum which is still dominated by landraces and varieties which have poor yield potentiality. Considering the necessity of development of heterotic hybrids, an attempt was made to screen hybrid parents (B and R lines) to assess variability and genetic diversity, for productivity traits. The study was conducted with 32 B and R lines at Regional Agricultural Research Station, Vijayapur during 2021-22. PCV was observed to surpass GCV across all traits. The traits grain yield per plant, fodder yield per plant, grain number per plant, and harvest index exhibited notably high PCV and GCV. Plant height, panicle length, panicle harvest index, and harvest index recorded high heritability and genetic advance, suggesting their control by additive gene action and potential for improvement via selection. Cluster analysis classified the 32 genotypes into four groups. PCA condensed 14 traits into five principal components, capturing 81.50% of total variation. The genotypes remained scattered in all four quadrants in PCA- Biplot, showing large genetic variability in quantitative traits studied. Keywords: Genetic variability, heritability, diversity, clusters, PCA and rabi sorghum

Bacteria as potential biocontrol agents for managing purple witchweed (Striga hermonthica) in grain sorghum

Abstract Purple witchweed [Striga hermonthica (Delile) Benth.], a highly destructive parasitic weed, poses a significant threat to sorghum [Sorghum bicolor (L.) Moench] cultivation. This hemiparasitic plant intrudes its root system into the host plant, leading to substantial yield losses, particularly in susceptible genotypes. In the pursuit of eco-friendly solutions, the biocontrol approach has gained attention as a potential management strategy for Striga. In this study, 13 bacterial strains belonging to the genera Bacillus, Gluconobacter, Pseudomonas, and Streptomyces were investigated in vitro for their efficiency in controlling the early-stage development of Striga. Among the tested strains, Streptomyces morookaensis NRRL B-12429 demonstrated significant inhibition of Striga seed germination and radicle elongation at 54.36% and 61.84%, respectively, when applied to preconditioned seeds with a synthetic germination stimulant. The effect of S. morookaensis on the inhibition of Striga seed germination was more pronounced in the presence of the host plant, sorghum, at 62.35%. However, biopriming of sorghum seeds with S. morookaensis did not enhance the inhibitory effects on Striga seed germination but resulted in a greater reduction in radicle elongation at 74.64% compared with non-primed seeds. Additionally, the biopriming with S. morookaensis promoted the growth of shoots and roots of germinating sorghum, regardless of the presence of Striga seeds. These findings highlight the potential of S. morookaensis strain NRRL B-12429 as a viable candidate for biocontrol agent applications in sorghum cultivation. Further exploration and investigation of its biocontrol capabilities can provide valuable insights for sustainable management practices against Striga infestations.

Impact of sewage sludge on growth indices of Sorghum bicolor: an alternative approach to conventional agriculture

Impact of sewage sludge on growth indices of Sorghum bicolor: an alternative approach to conventional agriculture

Allelic Diversity and Development of Breeder-Friendly Marker Specific to floury2 Gene Regulating the Accumulation of α-Zeins and Essential Amino Acids in Maize Kernel.

Maize zeins lack essential amino acids, such as methionine, lysine, and tryptophan. The floury2 (fl2) mutation reduces zein synthesis and increases methionine and lysine content in kernels. In this study, fl2 gene (1612bp) was sequenced in eight wild-type and two mutant inbreds and detected 218 SNPs and 18 InDels. Transversion of C to T at 343bp position caused the substitution of alanine by valine in the fl2 mutant. A PCR-based marker (FL-SNP-CT) was developed, which distinguished the favorable mutant fl2 allele (T) from the wild-type (C) Fl2 allele. Gene-based diversity analysis using seven gene-based InDel markers grouped 48 inbred lines into three major clusters, with an average genetic dissimilarity coefficient of 0.534. The average major allele frequency, gene diversity, heterozygosity, and polymorphism information content of the InDel markers were 0.701, 0.392, 0.039, and 0.318, respectively. Haplotype analysis revealed 29 haplotypes of fl2 gene among these 48 inbreds. Amino acid substitution (Ala-Val) at the signal peptide cleavage site produced unprocessed 24-kDa mutant protein instead of 22-kDa zein found in normal genotype. Eight paralogues of fl2 detected in the study showed variation in exon lengths (616-1170bp) and translation lengths (135-267 amino acids). Orthologue analysis among 15 accessions of Sorghum bicolor and two accessions of Saccharum spontaneum revealed a single exon in fl2 gene, ranging from 267 to 810bp. The study elucidated the molecular basis of fl2 mutation and reported a breeder-friendly marker for molecular breeding programs. This is the first study to characterize fl2 gene in a set of subtropically adapted inbreds.

The effect of agro-ecological zone on the chemical composition of feed resources in the Gera district, southwest Ethiopia

The poor quality of available feed resources is the major limiting factor for livestock production in Ethiopia. The aim of this study was to determine and compare the chemical composition of major feed resources in three agro-ecological zones (AEZs) of the Gera District, southwest Ethiopia. Three representative samples of natural pasture (Cynodon dactylon, Pavonia schimperiana Hochst and Rhynchosia ferruginea), three indigenous fodder trees and shrubs (IFTSs) (Erythrina abyssinica, Vernonia amygdalina and Maytenus undat), two cultivated forages (Pennisetum purpureum and Pennisetum pedicellatum) and five crop residues (Hordeum vulgare (barley), Zea mays (maize), Sorghum bicolor (sorghum), Triticum aestivum (wheat) and Eragrostis tef (Teff)) were randomly and separately collected from the Highland (HL), midland (ML) and lowland (LL) AEZs. The samples were analyzed for ash, dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE), and acid detergent lignin (ADL) content using standard analytical methods. The results showed that AEZ significant (P < 0.05) affected the chemical composition parameters of most of the feed samples. Regardless of the feed sample and AEZs, the mean DM, CP, ash, EE, NDF, ADF, ADL and CF content varied from 89.17% in Pennisetum purpureum to 92.22 ± 0.51 in Erythrina abyssinica, 2.90 ± 0.22% in Triticum aestivum to 10.70 ± 0.52 in Vernonia amygdalina, 7.24 ± 0.19% in Sorghum bicolor to 13.25 ± 0.51% in Pavonia Schimperiana Hochst, 1.33 ± 0.04% in Triticum aestivum to 2.39 ± 0.15% in Maytenus undata, 57.65 ± 1.19% in Erythrina Abyssinica to 79.16 ± 1.04% in Triticum aestivum, 34.57% in Pennisetum purpureum to 59.41 ± 0.98% in Sorghum bicolor, 8.15 ± 0.62% in Rhynchosia ferruginea to 12.65 ± 0.57% in Triticum aestivum and 37.51% in Pennisetum pedicelatum to 69.93 ± 0.65% DM in Triticum aestivum, respectively. It was observed that IFTSs had the highest CP and the lowest NDF, implying their potential for protein supplement, whereas crop residues had the lowest CP and the highest NDF, indicating the need for their treatment using urea or supplementing animals with protein source feeds, especially during the dry season. In conclusion, AEZ has an influence on the chemical composition traits of feed resources attributed to its effects on the microclimate conditions that affect plant growth and maturation in the study sites.

Evolution of plant cell-type-specific cis-regulatory elements.

Cis-regulatory elements (CREs) are critical in regulating gene expression, and yet understanding of CRE evolution remains challenging. Here, we constructed a comprehensive single-cell atlas of chromatin accessibility in Oryza sativa, integrating data from 103,911 nuclei representing 126 discrete cell states across nine distinct organs. We used comparative genomics to compare cell-type resolved chromatin accessibility between O. sativa and 57,552 nuclei from four additional grass species (Zea mays, Sorghum bicolor, Panicum miliaceum, and Urochloa fusca). Accessible chromatin regions (ACRs) had different levels of conservation depending on the degree of cell-type specificity. We found a complex relationship between ACRs with conserved noncoding sequences, cell-type specificity, conservation, and tissue-specific switching. Additionally, we found that epidermal ACRs were less conserved compared to other cell types, potentially indicating that more rapid regulatory evolution has occurred in the L1-derived epidermal layer of these species. Finally, we identified and characterized a conserved subset of ACRs that overlapped the repressive histone modification H3K27me3, implicating them as potentially silencer-like CREs maintained by evolution. Collectively, this comparative genomics approach highlights the dynamics of plant cell-type-specific CRE evolution.

Study on effect of plant growth promoting rhizobacteria on sorghum (Sorghum bicolor L.) under gnotobiotic conditions

The rhizosphere is enriched with diverse microflora, allowing for delving prospective microorganisms to enhance crop growth and yield for varied soil conditions. Demand for millet growth-promoting microorganisms is a contemporary need for dryland agriculture. Therefore, a detailed survey was conducted in northern Karnataka, India, to identify the millet growing areas, particularly sorghum. The rhizobacteria from the sorghum (Sorghum bicolor L.) were assessed for promoting seed germination using the paper towel method and classified based on their efficiency. The elite isolates were positive for indole-3-acetic acid (IAA), gibberellic acid (GA), phosphate, zinc oxide solubilization, and hydrogen cyanide (HCN) production. The test isolates were antagonistic to Macrophomina phaseolina and Fusarium sp. and inhibited completely. Further evaluation of the cultures on sorghum growth-promoting attributes under pot culture conditions showed that the plants inoculated with PG-152 (Bacillus subtilis) recorded the highest plant height, chlorophyll content, root dry weight, shoot dry weight, and total dry weight under ideal conditions of fertilization. Two isolates, namely, PG-152 and PG-197, performing superior under pot culture conditions, were identified as Bacillus subtilis and PG-197 as Enterobacter sp., respectively, using 16S rDNA analysis. The sequences were allowed to screen open reading frames (ORF) and found several ORFs in Enterobacter cloacae and Bacillus subtilis, respectively. This study found that the rhizosphere is vital for identifying prospective isolates for biocontrol and plant growth-improving microorganisms.

Synthesis and evaluation of esters obtained from phenols and phenoxyacetic acid with significant phytotoxic and cytogenotoxic activities.

There is a growing demand for herbicides that are more effective than conventional ones yet less harmful to ecosystems. In light of this, this study aimed to synthesize esters from phenols and phenoxyacetic acid, using compounds with known phytotoxic potential as starting materials. Phenoxyacetic acid was first synthesized and then utilized in the synthesis of seven esters through Steglich esterification, employing N,N'-dicyclohexylcarboimide and N,N-dimethylpyridin-4-amine in the presence of phenols (thymol, vanillin, eugenol, carvacrol, guaiacol, p-cresol, and β-naphthol), yielding esters 1-7. All synthesized compounds were characterized using mass spectrometry, 1H, and 13C NMR. These compounds were tested for phytotoxicity to evaluate their effects on the germination and root development of Sorghum bicolor and Lactuca sativa seeds, and for the induction of alterations in the mitotic cycle of meristematic cells of L. sativa roots. Esters 1, 3, 4, and 5 exhibited the most significant phytotoxic activity in both L. sativa and S. bicolor. Alterations in the mitotic index and frequency of chromosomal alterations in L. sativa roots revealed the cytotoxic, genotoxic effects, and the aneugenic mode of action of the tested molecules. These findings suggest that these compounds could serve as inspiration for the synthesis of new semi-synthetic herbicides.

Potassium supply for improvement of cereals growth under drought: A review

AbstractPotassium (K) is an essential macronutrient that determines crop productivity and promotes crop growth under conditions of abiotic stress. In this review paper, peer‐reviewed publications (experimental data) dealing with the role of K administration in the control of cereals growth under drought stress are reviewed and analyzed. Most published research on the impact of K administration on cereals growth under drought focuses primarily on bread wheat (Triticum aestivum L.) and maize (Zea mays L.), along with barley (Hordeum vulgare L.), rice (Oryza sativa L.), pearl millet (Pennisetum glaucum L.), and sorghum (Sorghum bicolor L.). The beneficial effect of K on cereals growth under drought has been related to maintenance of water balance in the crops, increased activity of the antioxidant enzymes, increased synthesis of osmolytes, contribution to a low sodium (Na)/K ratio, extension of the grain filling period, and increase of the grain growth rate and weight. Moreover, K was suggested as a possible way for enhancing nitrogen use efficiency (e.g., bread wheat and sorghum). Nevertheless, the beneficial effect of foliar applied K in dried soil during grain filling differed among bread wheat cultivars, highlighting that the effect of K supply on grain weight may differ depending on application method, that is, administration through the soil or the foliage. Overall, K supply could be exploited as a tool for increasing cereal tolerance to drought, for example, by considering late administration of K through top dressing applications or foliar sprayings. Yet additional information is needed on the rate and the K form, along with the most suitable growth stage for application. Such information could help agronomists develop strategies for high‐quality cereal production in stressful environments.

A powerful molecular marker to detect mutations at sorghum LOW GERMINATION STIMULANT 1.

The parasitic weed Striga (Striga hermonthica) limits productivity of sorghum (Sorghum bicolor) and other cereals in sub-Saharan Africa and elsewhere. Improved host plant genetics is an effective control method but verified loci contributing to Striga resistance are limited. LOW GERMINATION STIMULANT 1 remains the only known sorghum locus affecting resistance to Striga. Functional loss (lgs1) alleles at this locus result in low Striga germination stimulant activity. We developed a robust polymerase chain reaction (PCR)-based LGS1 marker that detects all known natural lgs1 alleles. We have successfully used this marker to improve Striga resistance in our sorghum breeding program. To check its utility among diverse sets of germplasm, we genotyped 406 lines of the sorghum association panel (SAP) with the marker and phenotyped them for Striga germination stimulant activity. The SAP contains 23 lines (6%) with lgs1 mutations that involve a complete loss of this gene. Three previously described deletion alleles (lgs1-1, lgs1-2, and lgs1-3) ranging from 28.5 to 34kbp are present among SAP members with a new one, lgs1-6, missing nearly 50kbp relative to the reference genome. All 23 members of the SAP carrying lgs1 alleles had low Striga germination stimulant activity. The smaller previously described intragenic deletion mutations lgs1-4 and lgs1-5 are not present in the SAP. The LGS1 marker is useful for both detecting sources of lgs1 and introgressing Striga resistance into new genetic backgrounds.

Genome-wide identification and expression analysis of the SWEET gene family in sweet sorghum (Sorghum dochna) and the role of SdSWEET01 in sugar transport

The SWEET sugar transporter plays a fundamental role in plant growth and development. In this study, 18 SWEET genes were identified from sweet sorghum (Sorghum dochna), encoding proteins with 231–336 amino acids, molecular weights from 25.15 to 35.69 kDa, and isoelectric points ranging between 6.41 and 9.69. Phylogenetic analysis categorized these proteins into four distinct subgroups. Examination of spatial expression patterns demonstrated that SdSWEET genes were expressed in a tissue-specific manner. Furthermore, their involvement in responses to various abiotic stresses, including cold, heat, drought, and salinity was observed. A yeast complementation assay verified that SdSWEET01, located on the plasma membrane, selectively transported glucose, sucrose, and galactose, while excluding fructose. Transgenic Arabidopsis expressing SdSWEET01 exhibited enhanced sugar absorption compared to wild-type plants, resulting in increased sensitivity and growth inhibition under high-sugar conditions. The study provides a detailed functional characterization of SdSWEET genes and emphasizes the critical role of SdSWEET01 in regulating sugar transport.

Structural insights to the RRM-domain of the glycine-rich RNA-binding protein from Sorghum bicolor and its role in cold stress tolerance in E. coli

Sorghum bicolor Glycine-rich RNA-binding protein (SbGRBP), exhibit the ability to bind both single-stranded and double-stranded DNA. The expression of SbGRBP is regulated by heat stress, with the protein localizing to the nucleus and cytosol. The present study delves into the structure and ssDNA binding ability of its truncated version (SbGRBP1–119) which lacks glycine rich domain (GR). This protein has the ability to bind ssDNA Using Nuclear Magnetic Resonance (NMR) spectroscopy, we have revealed the secondary structure of SbGRBP1–119, highlighting the typical configuration of GRBPs with four β-sheets and two α-helices. Notably, we found two additional α-helices at the N-terminal region that seem to interact with ssDNA, a novel observation for GRBPs. Key residues crucial for ssDNA binding were identified, suggesting a specific interaction with the oligonucleotide sequence 5’-TTCTGG-3′. Preliminary assays hinted that SbGRBP1–119 might bolster E. coli resilience to cold stress, indicating a potential chaperone-like role under stress conditions. This study sheds light on the structural basis of SbGRBP1–119's interaction with nucleic acids, deepening our understanding about the role of GRBPs' in RNA metabolism and regulation.

A review on the response of nitrogen management on yield, yield attributes &amp; quality of Forage Sorghum (Sorghum bicolor L.)

A review on the response of nitrogen management on yield, yield attributes &amp; quality of Forage Sorghum (Sorghum bicolor L.)

Sorghum bicolor polyphenol-rich extract improves insulin sensitivity and protect against chronic stress exacerbated diabetic nephropathy through modulation of Nrf2/NF-κB

IntroductionSorghum bicolor leaf sheath is known for its rich phytoconstituents 3-in deoxyanthocyanidins with protective and health benefits in targeting oxidative stress, inflammation and apoptosis. This study aimed to investigate Sorghum bicolor polyphenol-rich extract (SBPE) and its combination with metformin on insulin resistance and diabetic nephropathy in high-fat/streptozotocin-induced diabetic rats exposed to chronic stress. MethodsAntidiabetic and nephroprotective effects of SBPE was investigated in male Wistar rats fed with high-fat diet and injected streptozotocin (35 mg/kg) intraperitoneally. Diabetic rats were exposed to chronic unpredictable mild stress and orally treated with SBPE (200 mg/kg), metformin (250 mg/kg) and SBPE+metformin for 28 days. Kidney function parameters, FBS, insulin, adiponectin, kidney injury marker (KIM-1), triglycerides were determined. Renal tissues inflammatory (TNF-α, IL-1β, IL-10), oxidative stress, apoptotic (caspase-3,-9) and transcriptional factors (Nrf2 and NF-κB) were determined as well as histology. ResultsSBPE significantly reduced FBS, triglycerides insulin and parameters for insulin resistance in diabetic rats exposed to stress. Dysregulated electrolytes, urea, creatinine, adiponectin and KIM-1 were significantly reversed in SBPE and SBPE+metformin groups. SBPE treatment significantly reduced MDA, nitrites, TNF-α, and IL-1β levels, while GSH, catalase, SOD, GST and IL-10 were increased in renal tissues. Increased apoptotic markers (caspase-3, caspase-9) and NF-κB, along with reduced Nrf2 levels, were significantly reversed by SBPE and SBPE+metformin. Distorted kidney histomorphoarchitecture was reversed in SBPE-treated groups ConclusionSorghum bicolor polyphenol-rich extract and its combination with metformin showed promising antidiabetic effects in stress-exacerbated diabetes in rats through improving insulin sensitivity and nephroprotective mechanisms.

Effect of Rabbit Urine Bio Fertilizer and NPK on Vegetative Variables of Sorghum (Sorghum bicolor L.)

Sorghum (Sorghum bicolor L.) is a plant that requires more N nutrients than other nutrients. The abundance and affordability of rabbit urine bio fertilizer can reduce the cost of cultivation production inputs due to the high price of inorganic fertilizers. Rabbit urine contains higher N nutrients compared to other livestock urine. This study aims to obtain a combination of Rabbit Bio Urine (BUK) fertilizer concentration and NPK fertilizer dosage that can give the best results on the growth of sorghum plants (Sorghum bicolor L.). The research method used is a non-factorial Randomized Group Design (RAK) consisting of 6 levels, namely: P1 (BUK 0 ml/L + 100% NPK), P2 (BUK 41 ml/L + 80% NPK), P3 (BUK 27 ml/L + 80% NPK), P4 (BUK 18 ml/L + 80% NPK), P5 (BUK 9 ml/L + 80% NPK), and P6 (BUK 5 ml/L + 80% NPK). The application of rabbit bio urine fertilizer gives a real effect on the parameters of plant height and stem diameter at the age of 36 HST and 42 HST. In the parameter of the number of leaves, rabbit bio urine fertilizer and NPK gave no significant effect at all observation times. The P2 treatment (BUK 41 ml/L + NPK 80%) gave the highest results in the parameters of plant height at the age of 36 HST and 42 HST which amounted to 98,1 cm and 123,7 cm. In the parameter of stem diameter, the highest result was obtained by P1 (BUK 0 ml/L + NPK 100%) which amounted to 14,8 mm. Keywords : N Nutrient, Rabbit Urine Bio Fertilizer, Sorghum

Evaluation of new sorghum varieties for grain production cultivated in mineral soil

Sorghum bicolor L. (Sorghum) has been recognized as the fifth largest cereal crop in the world, following maize, wheat, rice, and barley, with a mean annual production of more than 5.89 million tons over the past five years. Grain sorghum is one of the cultivated varieties of the sorghum genus. It is primarily used as human food and animal feed due to the beneficial effects of bioactive compounds in the grain. Sorghum is less popular and unrecognizable in Malaysia, as it was not included in the reports by the Agriculture Department regarding plantation areas. In Malaysia, sorghum is limited because this crop is considered new, and no studies were conducted on the adaptability of its varieties to Malaysian soil and local climatic conditions. Crop production practices such as variety selection, planting density and fertilization will affect yield production. Therefore, a study on grain sorghum varieties (Brachy Sorgho, Jumbo Super, India and Pacific Seed 99) was conducted to evaluate the growth and yield performance of sorghum. Jumbo Super had a significantly higher value for plant height, followed by Brachy Sorgho, India and Pacific Seed 99. India showed the highest value of leaf fresh and dry weight, but no significant difference compared with Brachy Sorgho. Brachy Sorgho recorded the highest value of stem fresh and dry weight, while the least was recorded for Pacific Seed 99. Brachy Sorgho and India showed significantly higher grain yields than Jumbo Super and Pacific Seed 99 in terms of panicle length, panicle weight without grain, grain weight without panicle per plant, number of grains per panicle, and 100-grain weight. The highest gross weight of grain sorghum is Brachy Sorgho (140.00 g/plant), which showed no significant difference compared to the India variety (131.13 g/plant). Meanwhile, Jumbo Super and Pacific Seed 99 varieties showed the lowest grain weight, 77.27 g/plant and 80.16 g/plant, respectively. Overall, all four varieties are adaptable in mineral soil and are considered potential alternative crops for grain production. Bachy Sorgho and India varieties showed the best performance on grain yield compared to Jumbo Super and Pacific Seed 99 varieties. Thus, Brachy Sorgho and India varieties can be recommended for future grain production in mineral soil.

Altered Lignin Accumulation in Sorghum Mutated in Silicon Uptake Transporter SbLsi1.

Sorghum [Sorghum bicolor (L.) Moench] has been receiving attention as a feedstock for lignocellulose biomass energy. During the combustion process, the ash containing silicon (Si) can be produced, which causes problems in furnace maintenance. Hence, lowering Si content in the plants is crucial. Nevertheless, limiting Si supply to crops is difficult in practice because Si is abundant in soil. Previously, a Si uptake transporter (SbLsi1) has been identified, and the Si-depleted mutant has also been generated in the model sorghum variety BTx623. In this study, we aim to investigate the change induced by the mutation of SbLsi1 on the accumulation and the structure of lignin in cell walls. Through chemical and NMR analyses, we demonstrated that the lsi1 mutation resulted in a significant increase in lignin accumulation levels as well as a significant reduction in Si content. At least some of the modification was induced by transcriptional changes, as suggested by the upregulation of phenylpropanoid biosynthesis-related genes in the mutant plants. These findings derived from the model variety would be useful for the future development of practical cultivars with high biomass and less Si content for bioenergy applications.

Cover crop root exudates impact soil microbiome functional trajectories in agricultural soils

BackgroundCover cropping is an agricultural practice that uses secondary crops to support the growth of primary crops through various mechanisms including erosion control, weed suppression, nutrient management, and enhanced biodiversity. Cover crops may elicit some of these ecosystem services through chemical interactions with the soil microbiome via root exudation, or the release of plant metabolites from roots. Phytohormones are one metabolite type exuded by plants that activate the rhizosphere microbiome, yet managing this chemical interaction remains an untapped mechanism for optimizing plant-soil-microbiome interactions. Currently, there is limited understanding on the diversity of cover crop phytohormone root exudation patterns and our aim was to understand how phytochemical signals selectively enrich specific microbial taxa and functionalities in agricultural soils.ResultsHere, we link variability in cover crop root exudate composition to changes in soil microbiome functionality. Exudate chemical profiles from 4 cover crop species (Sorghum bicolor, Vicia villosa, Brassica napus, and Secale cereal) were used as the chemical inputs to decipher microbial responses. These distinct exudate profiles, along with a no exudate control, were amended to agricultural soil microcosms with microbial responses tracked over time using metabolomes and genome-resolved metatranscriptomes. Our findings illustrated microbial metabolic patterns were unique in response to cover crop exudate inputs over time, particularly by sorghum and cereal rye amended microcosms. In these microcosms, we identify novel microbial members (at the genera and family level) who produced IAA and GA4 over time. Additionally, we identified cover crop exudates exclusively enriched for bacterial nitrite oxidizers, while control microcosms were discriminated for nitrogen transport, mineralization, and assimilation, highlighting distinct changes in microbial nitrogen cycling in response to chemical inputs.ConclusionsWe highlight that root exudate amendments alter microbial community function (i.e., N cycling) and microbial phytohormone metabolisms, particularly in response to root exudates isolated from cereal rye and sorghum plants. Additionally, we constructed a soil microbial genomic catalog of microorganisms responding to commonly used cover crops, a public resource for agriculturally relevant microbes. Many of our exudate-stimulated microorganisms are representatives from poorly characterized or novel taxa, revealing the yet to be discovered metabolic reservoir harbored in agricultural soils. Our findings emphasize the tractability of high-resolution multi-omics approaches to investigate processes relevant for agricultural soils, opening the possibility of targeting specific soil biogeochemical outcomes through biological precision agricultural practices that use cover crops and the microbiome as levers for enhanced crop production.BPG5Z_iDvqR4KrAs2TcSTiVideo

An innovative formulation to improve spent coffee characteristics as soil fertilizer: Nutrient, chemical characterization and effects on plant germination

Spent coffee grounds (SCG) possess high organic content and various essential nutrients. However, their direct use as a fertilizer is limited due to high acidity, phenolic content, and C/N ratio. Therefore, in this study, SCG-based fertilizer (SCGf) was developed by mixing the raw SCG (SCGr) and zein through a granulation process and was compared with the SCGr. According to the obtained results, in SCGf, a reduction in the C/N ratio from 22.9 to 10.9, improved flowability from fair to good, an increase in the concentration of elements (N, C, S), nutrients (ash, fats, proteins), macrominerals (Ca, Mg, P, K, Na), microminerals (Cu, Fe, Mn, Zn), total polyphenolic content (TPC), total flavonoid content (TFC), and antioxidant activities (AOA) was noted. Additionally, a decrease in total organic acids, total chlorogenic acids, and was also observed in SCGf. Regarding phytotoxicity test results obtained by using Sinapis alba, Sorghum saccharatum, and Lepidium sativum and treating them with 2.5%, 5%, and 10% of SCGf and SCGr, better germination was observed for SCGf in S. alba (5%, 10%), L. sativum (2.5%, 5%). However, in L. sativum, 5% of SCGr and 10% of both SCGr and SCGf completely inhibited seed germination. For S. saccharatum, higher germination rates were observed for SCGf (2.5%, 10%), and at 5%, a comparable effect of both SCGf and SCGr was noted. SCGf gave the longest root length at all concentrations in all plants except for 2.5% in S. alba. In conclusion, this study addresses the effective use of SCG for sustainable agriculture while mitigating environmental impacts.