Alfalfa Research Articles

Phenotyping Alfalfa (Medicago sativa L.) Root Structure Architecture via Integrating Confident Machine Learning with ResNet-18.

Background: Root system architecture (RSA) is of growing interest in implementing plant improvements with belowground root traits. Modern computing technology applied to images offers new pathways forward to plant trait improvements and selection through RSA analysis (using images to discern/classify root types and traits). However, a major stumbling block to image-based RSA phenotyping is image label noise, which reduces the accuracies of models that take images as direct inputs. To address the label noise problem, this study utilized an artificial intelligence model capable of classifying the RSA of alfalfa (Medicago sativa L.) directly from images and coupled it with downstream label improvement methods. Images were compared with different model outputs with manual root classifications, and confident machine learning (CL) and reactive machine learning (RL) methods were tested to minimize the effects of subjective labeling to improve labeling and prediction accuracies. Results: The CL algorithm modestly improved the Random Forest model's overall prediction accuracy of the Minnesota dataset (1%) while larger gains in accuracy were observed with the ResNet-18 model results. The ResNet-18 cross-population prediction accuracy was improved (~8% to 13%) with CL compared to the original/preprocessed datasets. Training and testing data combinations with the highest accuracies (86%) resulted from the CL- and/or RL-corrected datasets for predicting taproot RSAs. Similarly, the highest accuracies achieved for the intermediate RSA class resulted from corrected data combinations. The highest overall accuracy (~75%) using the ResNet-18 model involved CL on a pooled dataset containing images from both sample locations. Conclusions: ResNet-18 DNN prediction accuracies of alfalfa RSA image labels are increased when CL and RL are employed. By increasing the dataset to reduce overfitting while concurrently finding and correcting image label errors, it is demonstrated here that accuracy increases by as much as ~11% to 13% can be achieved with semi-automated, computer-assisted preprocessing and data cleaning (CL/RL).

Complete genome of the Medicago anthracnose fungus, Colletotrichum destructivum, reveals a mini-chromosome-like region within a core chromosome.

Colletotrichum destructivum (Cd) is a phytopathogenic fungus causing significant economic losses on forage legume crops (Medicago and Trifolium species) worldwide. To gain insights into the genetic basis of fungal virulence and host specificity, we sequenced the genome of an isolate from Medicago sativa using long-read (PacBio) technology. The resulting genome assembly has a total length of 51.7 Mb and comprises ten core chromosomes and two accessory chromosomes, all of which were sequenced from telomere to telomere. A total of 15, 631 gene models were predicted, including genes encoding potentially pathogenicity-related proteins such as candidate-secreted effectors (484), secondary metabolism key enzymes (110) and carbohydrate-active enzymes (619). Synteny analysis revealed extensive structural rearrangements in the genome of Cd relative to the closely related Brassicaceae pathogen, Colletotrichum higginsianum. In addition, a 1.2 Mb species-specific region was detected within the largest core chromosome of Cd that has all the characteristics of fungal accessory chromosomes (transposon-rich, gene-poor, distinct codon usage), providing evidence for exchange between these two genomic compartments. This region was also unique in having undergone extensive intra-chromosomal segmental duplications. Our findings provide insights into the evolution of accessory regions and possible mechanisms for generating genetic diversity in this asexual fungal pathogen.

Remote sensing for estimating genetic parameters of biomass accumulation and modeling stability of growth curves in alfalfa.

Multi-spectral imaging by unoccupied aerial vehicles provides a non-destructive, high throughput approach to measuring biomass accumulation over successive alfalfa (Medicago sativa L. subsp. sativa) harvests. Information from estimated growth curves can be used to infer harvest biomass and to gain insights into the relationship between growth dynamics and forage biomass stability across cuttings and years. In this study, multi-spectral imaging and several common vegetation indices were used to estimate genetic parameters and model growth of alfalfa cultivars to determine the longitudinal relationship between vegetation indices and forage biomass. Results showed moderate heritability for vegetation indices, with median plot level heritability ranging from 0.11-0.64, across multiple cuttings in three trials planted in Ithaca, NY, and Las Cruces, NM. Genetic correlations between the normalized difference vegetation index and forage biomass were moderate to high across trials, cuttings, and the timing of multi-spectral image capture. To evaluate the relationship between growth parameters and forage biomass stability across cuttings and environmental conditions, random regression modeling approaches were used to estimate the growth parameters of cultivars for each cutting and the variance in growth was compared to the variance in genetic estimates of forage biomass yield across cuttings. These analyses revealed high correspondence between stability in growth parameters and stability of forage yield. The results of this study indicate that vegetation indices are effective at modeling genetic components of biomass accumulation, presenting opportunities for more efficient screening of cultivars and new longitudinal modeling approaches that can provide insights into temporal factors influencing cultivar stability.

Effect of alfalfa downy mildew (Peronospora aestivalis) infection on the growth and development of Therioaphis trifolii (Homoptera: Aphidiidae)

Downy mildew disease, which is caused by Peronospora aestivalis (Mastigomycotina: Peronosporaceae) and the spotted alfalfa aphid Therioaphis trifolii (Hemiptera: Aphididae), affects Medicago sativa (alfalfa) production. P. aestivalis and T. trifolii frequently occur together under natural conditions. In this study, alfalfa-P. aestivalis-T. trifolii were used as the research objects to explore the effects of different degrees of P. aestivalis infection on the growth and reproduction of T. trifolii, and the life table of T. trifolii population was constructed based on the fecundity parameters. The results revealed that alfalfa downy mildew infection had a significant effect on T. trifolii population. T. trifolii fed on mildly infected alfalfa plants exhibited the longest life span (18.9 d) and the highest number of nymphs (30.6) compared to those fed on alfalfa in other treatments. In terms of population life table parameters, the intrinsic rate of increase (0.626) and finite rate of increase (1.869) of T. trifolii fed on moderately infected alfalfa were the highest, and the generation time (8.310) and population doubling time (1.108) were the shortest, indicating that moderately infected alfalfa are conducive to T. trifolii population development. This study provides insights into the effects of alfalfa downy mildew on the main reproductive parameters and population of T. trifolii on M. sativa.

Influence of Adding Dehydrated Medicago sativa on the Nutritional Parameters Related to Hedychium gardnerianum Silage Quality

Influence of Adding Dehydrated Medicago sativa on the Nutritional Parameters Related to Hedychium gardnerianum Silage Quality

Comparative transcriptomic and metabolomic analyses provide insights into the responses to high temperature stress in Alfalfa (Medicago sativa L.)

High temperature stress is one of the most severe forms of abiotic stress in alfalfa. With the intensification of climate change, the frequency of high temperature stress will further increase in the future, which will bring challenges to the growth and development of alfalfa. Therefore, untargeted metabolomic and RNA-Seq profiling were implemented to unravel the possible alteration in alfalfa seedlings subjected to different temperature stress (25 ℃, 30 ℃, 35 ℃, 40 ℃) in this study. Results revealed that High temperature stress significantly altered some pivotal transcripts and metabolites. The number of differentially expressed genes (DEGs) markedly up and down-regulated was 1876 and 1524 in T30_vs_CK, 2, 815 and 2667 in T35_vs_CK, and 2115 and 2, 226 in T40_vs_CK, respectively. The number for significantly up-regulated and down-regulated differential metabolites was 173 and 73 in T30_vs_CK, 188 and 57 in T35_vs_CK, and 220 and 66 in T40_vs_CK, respectively. It is worth noting that metabolomics and transcriptomics co-analysis characterized enriched in plant hormone signal transduction (ko04705), glyoxylate and dicarboxylate metabolism (ko00630), from which some differentially expressed genes and differential metabolites participated. In particular, the content of hormone changed significantly under T40 stress, suggesting that maintaining normal hormone synthesis and metabolism may be an important way to improve the HTS tolerance of alfalfa. The qRT-PCR further showed that the expression pattern was similar to the expression abundance in the transcriptome. This study provides a practical and in-depth perspective from transcriptomics and metabolomics in investigating the effects conferred by temperature on plant growth and development, which provided the theoretical basis for breeding heat-resistant alfalfa.

The LTAR Integrated Common Experiment at Upper Mississippi River Basin-Platteville.

Alternative agronomic practices are needed to address the various climatic, agronomic, edaphic, and water quality related challenges faced by the dairy farmers of the Driftless Area (DA) in the Upper Mississippi River Basin (UMRB). These practices should be innovative in nature, inclusive of regional stakeholders, and sustainable to meet the future food and climate related challenges of Wisconsin agriculture. Here, we outline our Integrated (grazing and cropland) Long-Term Agroecosystem Research Common Experiment at the University of Wisconsin-Platteville Pioneer Farm (UW-P PF) in the UMRB and describe our collaboration in this USDA network. In this field-scale experiment, we are comparing the conventional dairy production system common to this region (i.e., corn-on-corn [Zea mays L.] for 4 years, followed by alfalfa [Medicago sativa L.] for 3 years, with no cover crops) with two alternative dairy production systems-(1) soil health management with no-till, cover crops, and application of a novel manure-based nutrient-rich stable product, and (2) management intensive grazing-and rotational grazing on pastures established with diverse forage-legume mix. Meteorological, edaphic, hydrologic, and agronomic data are collected and analyzed at regular frequencies. Going forward, the experiment will continue as a form of stakeholder-driven adaptive research and receive evaluation on a regular basis to determine whether any changes are required to address the "real-world" challenges faced by the farmers in the Midwest.

Genome-wide identification of SHMT family genes in alfalfa (Medicago sativa) and its functional analyses under various abiotic stresses

BackgroundAlfalfa (Medicago sativa L.) is the most widely planted legume forage and one of the most economically valuable crops in the world. Serine hydroxymethyltransferase (SHMT), a pyridoxal phosphate-dependent enzyme, plays crucial roles in plant growth, development, and stress responses. To date, there has been no comprehensive bioinformatics investigation conducted on the SHMT genes in M. sativa.ResultsHere, we systematically analyzed the phylogenetic relationship, expansion pattern, gene structure, cis-acting elements, and expression profile of the MsSHMT family genes. The result showed that a total of 15 SHMT members were identified from the M. sativa genome database. Phylogenetic analysis demonstrated that the MsSHMTs can be divided into 4 subgroups and conserved with other plant homologues. Gene structure analysis found that the exons of MsSHMTs ranges from 3 to 15. Analysis of cis-acting elements found that each of the MsSHMT genes contained different kinds of hormones and stress-related cis-acting elements in their promoter regions. Expression and function analysis revealed that MsSHMTs expressed in all plant tissues. qRT-PCR analysis showed that MsSHMTs induced by ABA, Salt, and drought stresses.ConclusionsThese results provided definite evidence that MsSHMTs might involve in growth, development and adversity responses in M. sativa, which laid a foundation for future functional studies of MsSHMTs.

Step-by-step optimization of a heterologous pathway for de novo naringenin production in Escherichia coli

Naringenin is a plant polyphenol, widely explored due to its interesting biological activities, namely anticancer, antioxidant, and anti-inflammatory. Due to its potential applications and attempt to overcome the industrial demand, there has been an increased interest in its heterologous production. The microbial biosynthetic pathway to produce naringenin is composed of tyrosine ammonia-lyase (TAL), 4-coumarate-CoA ligase (4CL), chalcone synthase (CHS), and chalcone isomerase (CHI). Herein, we targeted the efficient de novo production of naringenin in Escherichia coli by performing a step-by-step validation and optimization of the pathway. For that purpose, we first started by expressing two TAL genes from different sources in three different E. coli strains. The highest p-coumaric acid production (2.54 g/L) was obtained in the tyrosine-overproducing M-PAR-121 strain carrying TAL from Flavobacterium johnsoniae (FjTAL). Afterwards, this platform strain was used to express different combinations of 4CL and CHS genes from different sources. The highest naringenin chalcone production (560.2 mg/L) was achieved by expressing FjTAL combined with 4CL from Arabidopsis thaliana (At4CL) and CHS from Cucurbita maxima (CmCHS). Finally, different CHIs were tested and validated, and 765.9 mg/L of naringenin was produced by expressing CHI from Medicago sativa (MsCHI) combined with the other previously chosen genes. To our knowledge, this titer corresponds to the highest de novo production of naringenin reported so far in E. coli.Key points• Best enzyme and strain combination were selected for de novo naringenin production.• After genetic and operational optimizations, 765.9 mg/L of naringenin was produced.• This de novo production is the highest reported so far in E. coli.

Comparative proteomic discovery of salt stress response in alfalfa roots and overexpression of MsANN2 confers salt tolerance

Soil salinity constrains growth, development and yield of alfalfa (Medicago sativa L.). To illustrate the molecular mechanisms responsible for salt tolerance, a comparative proteome analysis was explored to characterize protein profiles of alfalfa seedling roots exposed to 100 and 200 mM NaCl for three weeks. There were 52 differentially expressed proteins identified, among which the mRNA expressions of 12 were verified by Real-Time-PCR analysis. The results showed increase in abundance of ascorbate peroxidase, POD, CBS protein and PR-10 in salt-stressed alfalfa, suggesting an effectively antioxidant and defense systems. Alfalfa enhanced protein quality control system to refold or degrade abnormal proteins induced by salt stress through upregulation of unfolded protein response (UPR) marker PDIs and molecular chaperones (eg. HSP70, TCP-1, and GroES) as well as the ubiquitin‐proteasome system (UPS) including ubiquitin ligase enzyme (E3) and proteasome subunits. Upregulation of proteins responsible for calcium signal transduction including calmodulin and annexin helped alfalfa adapt to salt stress. Specifically, annexin (MsANN2), a key Ca2+-binding protein, was selected for further characterization. The heterologous of the MsANN2 in Arabidopsis conferred salt tolerance. These results provide detailed information for salt-responsive root proteins and highlight the importance of MsANN2 in adapting to salt stress in alfalfa.

Genome-Wide Identification of Caffeic Acid O-Methyltransferase Gene Family in Medicago truncatula: MtCOMT13-Mediated Salt and Drought Tolerance Enhancement

Legumes are important grains and forages, providing high-quality proteins, vitamins, and micronutrients to humans and animals. Medicago truncatula is a close relative of alfalfa (Medicago sativa). Caffeic acid O-methyltransferase (COMT), a key gene that is identified to be essential for melatonin synthesis, plays a significant role in plant growth, development, and abiotic stress responses. However, a systematic study on the COMT gene family in M. truncatula has still not been reported. In this study, 63 MtCOMT genes were identified and categorized into three groups. Gene structure and conserved motif analyses revealed the relative conservation of closely clustered MtCOMTs within each group. Duplicated events in MtCOMT members were identified, and segmental duplication was the main mean. Cis-acting element prediction revealed the involvement of MtCOMTs in growth and development and response to light, stress, and plant hormones. RNA-seq data analysis showed that 57 MtCOMTs varied under salt and drought stresses. The RT-qPCR expression patterns showed that MtCOMT9, MtCOMT13, MtCOMT22, MtCOMT24, MtCOMT43, and MtCOMT46 were related to salt and drought responses in M. truncatula. Additionally, Arabidopsis thaliana overexpressing MtCOMT13 displayed superior plant growth phenotypes and enhanced tolerance to salt and drought stresses through higher photosynthetic parameters and activities of antioxidant enzymes, which indicated that MtCOMT13 played an important role in positively regulating plant salt and drought tolerance. These findings contribute to an improved understanding of MtCOMTs’ roles in abiotic stress responses in M. truncatula, providing an important theoretical basis and genetic resource for legume species resistance breeding in the future.

Green Synthesis, Characterization and Biological activity of Optimized Alfalfa‐Mediated Zirconium Nanoparticles

AbstractNanoparticle green synthesis is an emerging scientific field that focuses on the production of nanoparticles by living cells. In this work, the potential of extracts of alfalfa leaves (Medicago sativa) as affordable and fabricated zirconium nanoparticles (ZrNPs) was evaluated for the first time. alfalfa alcoholic extract and zirconium precursor were used to produce ZrNPs, the production and characteristics of nanoparticles were measured using the Tyndall effect, UV‐vis, FT‐IR, EDX, DLS, and SEM tests, antioxidant and antibacterial properties, and toxicity Measurement of nanoparticles on breast cancer (MDA‐MB‐468) and human healthy cells (HFF) was investigated. The optimization of nanoparticle production was evaluated with ANN and GN algorithms. The analysis showed that nanoparticles have spherical‐like ZrNPs shapes with an average of 50 nm size. in addition, ZrNPs have significant cytotoxic effects against human breast cancer (MDA‐MB‐468) cells, and Human foreskin fibroblast (HFF) cells exhibited the highest resistance to ZrNPs. There was a significant agreement between the results of the designed ANN‐GA model and the experimental data. In this research, ZrNP was successfully created using alfalfa extract as a renewable source of stabilizing and reducing agents with an environmentally friendly approach, and they showed significant antioxidant, antibacterial, and anticancer properties.

Transcriptome analysis reveals candidate genes for different root types of alfalfa (Medicago sativa) after water stress induced by PEG-6000

BackgroundWe aimed to gain insight into the response mechanism of alfalfa (Medicago sativa) to drought stress by recognizing and analyzing drought-responsive genes in the roots of different root types of alfalfa. The rhizomatous-rooted M. sativa cv.‘Qingshui’ (QS), tap-rooted M. sativa cv.‘Longdong’ (LD), and creeping-rooted M. varia cv. ‘Gongnong No. 4’ (GN) were used to analyze the transcriptome information and physiological characteristics of the root systems of the cultivars under simulated drought stress using PEG-6000.ResultsIt was found that aridity caused a significant increase in the content of osmotic stress substances and antioxidant enzyme activity. The content of malondialdehyde (MDA) in QS was lower than that in LD and GN under moisture stress, indicating a stronger accumulation capacity of osmotic regulatory substances. Based on sequencing results, 14,475, 9336, and 9243 upregulated DEGs from QS, LD, and GN were annotated into 26, 29, and 28 transcription factor families, respectively. QS showed more DEGs than LD and GN. KEGG enrichment analysis identified that DEGs were significantly enriched in metabolic pathways such as amino acid biosynthesis, phenylpropanoid biosynthesis, plant hormone signaling transduction, and MAPK pathways. This suggests a strong correlation between these pathways and drought stress. The results also show that genes associated with ABA hormone signaling (MS. gene93372, MS. gene072046, and MS. gene012975) are crucial for plant’s adaptation to drought stress.ConclusionsThese genes, such as serine/threonine protein kinases and abscisic acid receptors, play a crucial role in plant hormone signaling and MAPK pathways. They could serve as potential candidate genes for drought resistance research in alfalfa, providing a molecular foundation for studying drought resistance.Graphical

Alfalfa‐bermudagrass mixtures managed under contrasting harvest strategies in the southeastern US

AbstractThe incorporation of dual‐purpose alfalfa (Medicago sativa L.) cultivars into bermudagrass (Cynodon spp.) is a viable option to extend the grazing season in Southern forage systems. However, data are limited on which harvest management strategy (HMS) optimizes the use of alfalfa‐bermudagrass (ABG) mixtures in the Southern US. A two‐year study evaluated ABG mixtures under three HMS [cut only (CO), graze only (GO), or cut and graze (CG)].in Headland, AL and Tifton, GA. Alfalfa‐bermudagrass mixtures utilized in this evaluation were ‘Bulldog 805’ alfalfa that was interseeded into ‘Tifton 85’ bermudagrass. Treatments were evaluated for forage, animal, and total system performance. Herbage accumulation varied by year and location (p < .01), but the number of harvests ultimately determined the total forage produced. Forage allowance was never limiting but did differ among treatments at Tifton, GA (p = .02). The CG HMS allowed for similar daily (p > .06) and liveweight gains (p > .56) on fewer days of grazing as compared to the GO treatments. The greater alfalfa percentage in the CG HMS translated to greater total digestible nutrients (TDN) and crude protein (CP), though not always statistically different. The CO HMS maximized system performance when evaluated for total gain (actual gains + predicted gains). However, the CG management allowed for more production opportunities across the season, thereby reducing economic risk. Future research should focus on evaluating the economic implications of introducing each HMS into ABG systems.

Phosphorus fertilization enhanced overwintering, root system and forage yield of late-seeded alfalfa in sodic soils

Sowing date and soil fertility are very important factors in the overwintering and production performance of alfalfa (Medicago sativa L.), yet there’s a knowledge gap in knowledge on how late-seeded alfalfa responds to phosphorus (P) fertilization. A field study was conducted in Inner Mongolia from 2020 to 2022 using a split-plot design. The main plots consisted of five sowing dates (31 July, 8, 16, and 24 August, and 1 September), while the subplots involved five P application rates (0, 40, 70, 100, and 130 kg P2O5 ha−1). Throughout the growing seasons, the overwintering rate, root traits, forage yield, and yield components were measured. The results revealed a consistent decrease in overwintering ability and productivity with the delayed sowing. This reduction in overwintering rate was mainly due to diminished root traits, while the decrease in forage yield was largely associated with a reduction in plants per square meter. However, P fertilizer application to late-seeded alfalfa demonstrated potential in enhancing the diameter of both the crown and taproot, thus strengthening the root system and improving the overwintering rate, the rate of increase ranges from 11.6 to 49%. This adjustment could also improve the shoots per square meter and mass per shoot, increasing by 9.4–31.3% and 15.0–27.1% respectively in 2 years, which can offset the decline in forage yield caused by late sowing and might even increase the forage yield. Regression and path analysis indicated that alfalfa forage yield is primarily affected by mass per shoot rather than shoots per square meter. This study recommended that the sowing of alfalfa in similar regions of Inner Mongolia should not be later than mid-August. Moreover, applying P fertilizer (P2O5) at 70.6–85.9 kg ha−1 can enhance the forage yield and persistence of late-seeded alfalfa. Therefore, appropriate late sowing combined with the application of P fertilizer can be used as an efficient cultivation strategy for alfalfa cultivation after a short-season crop harvest in arid and cold regions.

Phenanthrene-Degrading and Nickel-Resistant Neorhizobium Strain Isolated from Hydrocarbon-Contaminated Rhizosphere of Medicago sativa L.

Pollutant degradation and heavy-metal resistance may be important features of the rhizobia, making them promising agents for environment cleanup biotechnology. The degradation of phenanthrene, a three-ring polycyclic aromatic hydrocarbon (PAH), by the rhizobial strain Rsf11 isolated from the oil-polluted rhizosphere of alfalfa and the influence of nickel ions on this process were studied. On the basis of whole-genome and polyphasic taxonomy, the bacterium Rsf11 represent a novel species of the genus Neorhizobium, so the name Neorhizobium phenanthreniclasticum sp. nov. was proposed. Analysis of phenanthrene degradation by the Rsf1 strain revealed 1-hydroxy-2-naphthoic acid as the key intermediate and the activity of two enzymes apparently involved in PAH degradation. It was also shown that the nickel resistance of Rsf11 was connected with the extracellular adsorption of metal by EPS. The joint presence of phenanthrene and nickel in the medium reduced the degradation of PAH by the microorganism, apparently due to the inhibition of microbial growth but not due to the inhibition of the activity of the PAH degradation enzymes. Genes potentially involved in PAH catabolism and nickel resistance were discovered in the microorganism studied. N. phenanthreniclasticum strain Rsf11 can be considered as a promising candidate for use in the bioremediation of mixed PAH-heavy-metal contamination.

Transcriptomic analyses provide molecular insight into the cold stress response of cold-tolerant alfalfa

BackgroundDaye No.3 is a novel cultivar of alfalfa (Medicago sativa L.) that is well suited for cultivation in high-altitude regions such as the Qinghai‒Tibet Plateau owing to its high yield and notable cold resistance. However, the limited availability of transcriptomic information has hindered our investigation into the potential mechanisms of cold tolerance in this cultivar. Consequently, we conducted de novo transcriptome assembly to overcome this limitation. Subsequently, we compared the patterns of gene expression in Daye No. 3 during cold acclimatization and exposure to cold stress at various time points.ResultsA total of 15 alfalfa samples were included in the transcriptome assembly, resulting in 141.97 Gb of clean bases. A total of 441 DEGs were induced by cold acclimation, while 4525, 5016, and 8056 DEGs were identified at 12 h, 24 h, and 36 h after prolonged cold stress at 4 °C, respectively. The consistency between the RT‒qPCR and transcriptome data confirmed the accuracy and reliability of the transcriptomic data. KEGG enrichment analysis revealed that many genes related to photosynthesis were enriched under cold stress. STEM analysis demonstrated that genes involved in nitrogen metabolism and the TCA cycle were consistently upregulated under cold stress, while genes associated with photosynthesis, particularly antenna protein genes, were downregulated. PPI network analysis revealed that ubiquitination-related ribosomal proteins act as hub genes in response to cold stress. Additionally, the plant hormone signaling pathway was activated under cold stress, suggesting its vital role in the cold stress response of alfalfa.ConclusionsUbiquitination-related ribosomal proteins induced by cold acclimation play a crucial role in early cold signal transduction. As hub genes, these ubiquitination-related ribosomal proteins regulate a multitude of downstream genes in response to cold stress. The upregulation of genes related to nitrogen metabolism and the TCA cycle and the activation of the plant hormone signaling pathway contribute to the enhanced cold tolerance of alfalfa.

Effect of Ozone on Enterobacteriaceae Counts in Wheat Grain, Alfalfa, Radish, Broccoli Seeds and Sprouts

Abstract The sprouts of various seeds have garnered considerable regard amid consumers due to its verdure, crispiness, and germination potential, offering a cost-effective and straightforward process. The moist and warm conditions are very conducive to germination, fostering the growth of microorganisms and thereby raising food safety concerns. The aim of the study was to investigate the impact of ozone on Enterobacteriaceae counts by subjecting wheat (Triticum aestivum) grains, alfalfa (Medicago sativa), radish (Raphanus sativus) and broccoli (Brassica oleracea) seeds to ozone gas treatment. Additionally, the grain and seeds were rinsed with ozonated water during germination. Three different treatment methods were employed for seeds and grains. In the first method, samples were exposed to ozone gas at 20 ppm for 10 minutes, with subsequent rinsing every 12 hours during germination until the rinse water appeared visually clean, at a concentration of 2.0 mg L−1 of ozone. The second method involved rinsing with ozonated water at a concentration of 2.0 mg L−1 for durations of 20, 40, and 60 minutes. The third method - treated with ozone gas at 50 ppm and the exposure time of 1, 2, 3, 4 and 5 h. Untreated samples were used as controls. Evaluation of the samples revealed that Enterobacteriaceae was virtually undetectable in dry seeds. However, after 72 hours of germination in both the control and ozone-treated sprouts and following 7 days of storage at 4±2 °C, Enterobacteriaceae were found at an average of 7 to 8.1 log CFU g−1 in all samples, irrespective of the treatment method. Additionally, mould was observed only in wheat and radish sprouts during the assessment period. The study showed that there was no significant reduction in the number of mesophilic aerobic and facultative anaerobic microorganisms, moulds and Enterobacteriaceae then treated with ozone gas.

Constitutive expression of MsPROPEP1 enhances salinity and drought tolerance in alfalfa (Medicago sativa)

Constitutive expression of MsPROPEP1 enhances salinity and drought tolerance in alfalfa (Medicago sativa)

Transfer of Metals from the Soil to <i>Medicago sativa</i> Irrigated with Municipal Landfill Leachate

Transfer of Metals from the Soil to <i>Medicago sativa</i> Irrigated with Municipal Landfill Leachate