Later Stages Of Maturation Research Articles

NUTRITIVE VALUE OF GUATEMALA GRASS (Tripsacum andersonii) HARVESTED AT THREE STAGES OF MATURITY IN GEDEO AGROFORESTRY SYSTEMS, SOUTHERN ETHIOPIA

<div class="WordSection1"><p><strong>Background:</strong> Gedeo agroforestry is characterized as the integration of trees, crops and livestock on the same unit of land. Land scarcity is a common characteristic in the Gedeo agroforestry system. Hence integrating forage crops with the agroforestry system is one of the options to alleviate feed scarcity in the area. <strong>Objectives:</strong> To evaluate the biomass yield and nutritional value of Guatemala grass harvested at three stages of maturity: Early (120days), Mid (150days) and Late (180 days) cultivated at three different altitudes (high, medium and low). <strong>Methodology:</strong> A randomized complete block design with three replications was employed. Morphological parameters and chemical composition were measured at each stage of maturity and altitude. <strong>Result:</strong> The results showed that the number of leaves per plant (NL), plant height (PH), leaf length (LL) and dry matter yield (DMY) exhibited (p<0.05) an increasing trend as harvesting days were delayed. Contrarily the number of tillers (NT) showed (p<0.05) decreasing trend as harvesting dates advanced. The highest (p<0.05) CP (12.6±0.25%DM) was recorded at 120 days. The highest (p<0.05) NDF (61.27±0.07%DM) and ADF (42.3±0.91%DM) were recorded at 180 days of harvesting. The highest (p<0.05) IVDMD (56.7±1.97%) was recorded at 120 days of harvesting, whereas the least (p<0.05) (48.0±2.06) was at 180 days of harvesting. Generally, as the harvesting date advanced, CP and IVDMD showed a decreasing trend, whereas the fiber content (ADF, NDF and ADL) showed an increasing trend. <strong>Implication:</strong> Based on the morphological characteristics and dry matter yield, the best harvesting stage of Guatemala grass was at the late (180days) stage of maturity. On the other hand, considering the chemical composition and IVDMD, the best harvest stage was at the early (120days) stage of maturity. <strong>Conclusion:</strong> Cutting Guatemala grass at the proper growth stage is crucial for forage management. However, to fully utilize the potential of Guatemala grass, further studies on live animal experiments should be carried out.</p></div>

Transcriptome Profiling and Identification of the Candidate Genes Involved in Early Ripening in Ziziphus Jujuba.

The early ripening jujube is an immensely popular fresh fruit due to its high commercial value as well as rich nutrition. However, little is known about the mechanism of jujube fruit’s ripening. In this study, the transcriptome profiles were comprehensively analyzed between the ‘Lingwu Changzao’ jujube and its early-ripening mutant during the fruit development and maturity. A total of 5,376 and 762 differentially expressed genes (DEGs) were presented at 80 and 90 days after the flowering of the jujube fruit, respectively. Furthermore, 521 common DEGs were identified as candidate genes that might be associated with the fruit’s early ripening. Our findings demonstrated that in a non-climacteric jujube fruit, abscisic acid (ABA) was more greatly involved in fruit ripening than ethylene. Meanwhile, the fruit ripening of the early-ripening mutant was regulated by eight promotors of DEGs related to glucose and fructose, seven repressors of DEGs related to brassinosteroid signal transduction, and a series of transcription factor genes (MYB, Bhlh, and ERF). Additionally, the expression of 20 candidate DEGs was further validated by real-time PCR during the late fruit maturation stage. Collectively, the present study sheds light on the metabolic mechanism of the fruit’s early ripening and provides valuable candidate genes for the early-ripening mutant’s breeding.

Nitrogen Source Matters: High NH4/NO3 Ratio Reduces Cannabinoids, Terpenoids, and Yield in Medical Cannabis.

The N form supplied to the plant, ammonium (NH4+) or nitrate (NO3–), is a major factor determining the impact of N nutrition on plant function and metabolic responses. We have hypothesized that the ratio of NH4/NO3 supplied to cannabis plants affects the physiological function and the biosynthesis of cannabinoids and terpenoids, which are major factors in the cannabis industry. To evaluate the hypothesis we examined the impact of five supply ratios of NH4/NO3 (0, 10, 30, 50, and 100% N-NH4+, under a uniform level of 200 mg L–1 N) on plant response. The plants were grown in pots, under controlled environment conditions. The results revealed high sensitivity of cannabinoid and terpenoid concentrations and plant function to NH4/NO3 ratio, thus supporting the hypothesis. The increase in NH4 supply generally caused an adverse response: Secondary metabolite production, inflorescence yield, plant height, inflorescence length, transpiration and photosynthesis rates, stomatal conductance, and chlorophyll content, were highest under NO3 nutrition when no NH4 was supplied. Ratios of 10–30% NH4 did not substantially impair secondary metabolism and plant function, but produced smaller inflorescences and lower inflorescence yield compared with only NO3 nutrition. Under a level of 50% NH4, the plants demonstrated toxicity symptoms, which appeared only at late stages of plant maturation, and 100% NH4 induced substantial plant damage, resulting in plant death. This study demonstrates a dramatic impact of N form on cannabis plant function and production, with a 46% decrease in inflorescence yield with the increase in NH4 supply from 0 to 50%. Yet, moderate levels of 10–30% NH4 are suitable for medical cannabis cultivation, as they do not damage plant function and show only little adverse influence on yield and cannabinoid production. Higher NH4/NO3 ratios, containing above 30% NH4, are not recommended since they increase the potential for a severe and fatal NH4 toxicity damage.

Metabolic adaptation of ‘Conference’ pear to postharvest hypoxia: The impact of harvest time and hypoxic pre-treatments

The choice of harvest time and low oxygen storage conditions are crucial parameters in the commercialization of ‘Conference’ pear and the prevention of market losses. To elucidate the effect of harvesting time and hypoxia on the metabolic adaptational responses in pear fruit, a 13C-feeding experiment was performed. Pear tissue disks obtained from fruit harvested at optimum harvest time, or 1 week earlier or later (commercial, early, and late maturity stages, respectively) were exposed for 24 h to 21 kPa O2 followed by 24 h incubation at 0.2 kPa O2 at a constant temperature of 18 °C in a liquid medium containing [U13C] sodium pyruvate. Results showed high fractional enrichment of organic acids, succinate, α-ketoglutarate and lactate, and amino acids, glutamate, and alanine, during hypoxia for all harvesting times suggesting a downregulated TCA cycle stopping at succinate, as suggested by its accumulation, and a possible upregulation of the γ-aminobutyric acid (GABA) shunt. Increased concentration of alanine under hypoxia only in late pears was connected to increased endogenous levels of ethanol and acetaldehyde prior the experiment and lower lactate enrichment. Concentration and fractional enrichment of the optimum harvest time under 0.2 kPa O2 were compared to previously published data from a similar experimental setup where a 4-day gradually declining hypoxic prolife from 21 kPa to 0.2 kPa was implemented. Results showed similar enrichment for all TCA cycle organic acids. Faster label propagation of lactate in the pre-treated tissue suggested faster adaptational mechanisms and an already initiated hypoxic response while higher concentration and enrichment of alanine in the non-acclimated fruit could be evidence of a tissue specific alanine response to sudden oxygen shortage or aneffect of the age of the acclimated sample.

Effects of Medium Supplements on Somatic Embryo Maturation and DNA Methylation in Pseudotsuga gaussenii Flous, a Species under Protection

Pseudotsuga gaussenii is a forest species under protection in China. Propagation via somatic embryogenesis is efficient and needed for recovering this species. In this research, effects of medium supplements, i.e., methylglyoxal-bis (guanylhydrazone) (MGBG), polyethylene glycol (PEG), and maltose, on somatic embryo (SE) development were studied. More mature SEs developed with the pre-maturation treatment medium supplemented with 50 μM or 100 μM MGBG. During SE maturation, when the medium was supplemented with both PEG and maltose, the over-proliferation of embryogenic tissue was suppressed. When maltose was eliminated from the maturation medium, SEs were slightly smaller but developed better than other treatments due to the supply of lower carbon source, whereas when PEG was taken out from the maturation medium, no mature SE was obtained, only the heavily-proliferated plant tissue. Meanwhile, DNA methylation levels differed in these SE maturation cultures at the late culture stage of SE maturation. The level increased sharply with no maltose treatment (20.28%) while decreasing without PEG supplement (10.35%). DNA methyltransferase genes MET1-1, MET1-2, MET1-3, CMT3, DRM1, and DRM2 were partially cloned in this study to detect their expression level via qPCR. Expression of these genes, except MET1-3, in the culture of no PEG was higher significantly than the cultures of other treatments at weeks 1, 3, and 10. Our results suggested that MGBG and/or PEG play an important role in stimulating SE development and maturation. Furthermore, sugar supplements at a lower level benefited SE maturation in Pseudotsuga gaussenii.

Cytology, transcriptomics, and mass spectrometry imaging reveal changes in late-maturation elm (Ulmus pumila) seeds

During seed maturation, the seed deposits storage compounds (starches, oils, and proteins), synthesizes defense compounds, produces a seed coat, initiates embryo dormancy, and becomes desiccated. During the late-maturation stage, seed storage compound contents and compositions change dramatically. Although maturation has been extensively studied in model species and crops, it remains less well characterized in woody perennial plants. In this study, we conducted morphological and cytological observations, transcriptome profiling, and chemical constituent analysis of elm (Ulmus pumila L.) seeds during the late-maturation stage. Light and electron microscopy revealed that closely packed yet discrete lipid bodies frequently surrounded the densely stained protein bodies, and the protein bodies became irregular or even partially disintegrated at the end of seed development. RNA-seq detected substantial transcriptome changes during the late-maturation stage, and pathway enrichment analysis showed that the differentially expressed genes were associated with phenylpropanoid biosynthesis, starch and sucrose metabolism, plant–pathogen interactions, and hormone signal transduction. Furthermore, we used mass spectrometry imaging to detect the relative intensity and spatial distribution of fatty acids, phospholipids, and waxes in elm seeds. Our findings provide a framework for understanding the changes in cytological features and chemical composition during the final stage of elm seed development, and a detailed reference for seed development in woody plants.

Field mold stress induced catabolism of storage reserves in soybean seed and the resulting deterioration of seed quality in the field

Excessive rainfall provides a favorable condition for field mold infection of plants, which triggers field mold (FM) stress. If FM stress occurs during the late maturation stage of soybean seed, it negatively affects seed yield and quality. To investigate the responses of soybean seed against FM stress and identify the underlying biochemical pathways involved, a greenhouse was equipped with an artificial rain producing system to allow the induction of mold growth on soybean seed. The induced quality changes and stress responses were revealed on the levels of both transcriptome and metabolome. The results showed that soybean seeds produced under FM stress conditions had an abnormal and inferior appearance, and also contained less storage reserves, such as protein and polysaccharide. Transcriptional analysis demonstrated that genes involved in amino acid metabolism, glycolysis, tricarboxylic acid, β-oxidation of fatty acids, and isoflavone biosynthesis were induced by FM stress. These results were supported by a multiple metabolic analysis which exhibited increases in the concentrations of a variety of amino acids, sugars, organic acids, and isoflavones, as well as reductions of several fatty acids. Reprogramming of these metabolic pathways mobilized and consumed stored protein, sugar and fatty acid reserves in the soybean seed in order to meet the energy and substrate demand on the defense system, but led to deterioration of seed quality. In general, FM stress induced catabolism of storage reserves and diminished the quality of soybean seed in the field. This study provides a more profound insight into seed deterioration caused by FM stress.

Difference Between Coloration and Endogenous Abscisic Acid Accumulation Patterns in Two Red Grape Cultivars, ‘Aki Queen’ and ‘Ruby Roman’ (<i>Vitis labruscana</i> Bailey) Berries

Changes in anthocyanin and endogenous abscisic acid (ABA) contents in the berry skins of Vitis labruscana × V. vinifera cultivars, ‘Aki Queen’, and ‘Ruby Roman’ were investigated during the fruit development period. Color development of ‘Aki Queen’ berries mainly occurred within 20 days post véraison, while that of the ‘Ruby Roman’ was prolonged for about 40 days. In both cultivars, the ABA level in the berry skin started to increase a few days before véraison; however, ABA accumulation ceased approximately 10 days after véraison in ‘Aki Queen’, while it continued until the late stage of maturation in ‘Ruby Roman’. In addition, higher indole-3-acetate aspartate (IAA-Asp) and lower isopentenyladenine (iP) contents were observed in ‘Ruby Roman’ than in ‘Aki Queen’ at the late development stage. The expression analysis of genes involved in ABA metabolism revealed that V. vinifera 9-cis-epoxycarotenoid dioxygenase 3 (VviNCED3), which is assumed to play a major role in ABA biosynthesis, remained relatively higher in ‘Ruby Roman’ than in ‘Aki Queen’ after véraison. Considering that ABA plays a regulatory role in grape maturation, these results may indicate that the coloration of ‘Ruby Roman’ at the later stage of maturation is partly attributable to an increased ABA pool in berry skins.

Effect of harvest time on the chemical composition and antioxidant capacity of Gannan navel orange (Citrus sinensis L. Osbeck ‘Newhall’) juice

The present study investigates the chemical composition and antioxidant capacity of juice from the Gannan navel orange, which is harvested at one- to two-week intervals during the ripening period. The total soluble solid (TSS), total polyphenol content (TPC), total flavonoid content (TFC), sucrose and hesperidin contents gradually increase with the ripening of the fruit, followed by slight declines at the late maturity stage. Contrary to these observations, the contents of titratable acid (TA), vitamin C (Vc), and limonin trend downward throughout the ripening period. However, the contents of fructose, glucose, and narirutin fluctuate throughout the harvest time. Three in vitro antioxidant assays consistently indicate that the harvest time exerts no significant influence (P>0.01) on the antioxidant capacity. Furthermore, principal component analysis (PCA) and Pearson's correlation test are performed to provide an overview of the complete dataset. This study provides valuable information for evaluating the fruit quality and determining when to harvest the fruit in order to meet the preferences of consumers. Meanwhile, our observations suggest that the fruits subjected to juice processing should be harvested at the late maturity stage to alleviate the “delayed bitterness” problem without compromising the antioxidant capacity and the flavonoid content in the juice.

Source rock pyrolysis and bulk kinetic modelling of Miocene sedimentary sequences in southeastern Sabah, Malaysia: The variability of thermal maturity to oil-gas producing kerogen

The study reports a new organic geochemical evaluation for a petroleum source rock in the Southeastern (SE) Sabah basin. The analyses focus on Kalabakan, Tanjong, and Kapilit Formation deposited in the deltaic-shallow marine environment stratigraphically from the Early to Late Miocene sequences. The basin sediments are part of the hydrocarbon prolific Tarakan basin, extending from the northernmost of Kalimantan Indonesia to the southeastern Sabah (mainly onshore area). The hydrocarbon generation of Kapilit and Tanjong Formation pinnacles the Total Organic Carbon (TOC) contents that range from 0.62 to 81.97 wt% and 0.97–92.96 wt% respectively. The dominant black shale in Kalabakan Formation has lower TOC content between 0.50 and 1.82 wt%. The results in the Rock-Eval S2 of Kapilit (0.31–351.61 mg HC/g rock) and Tanjong Formation (3.32–239.78 mg HC/g rock) have excellent source rock potential compared to the Kalabakan Formation (0.12–1.19 mg C/g rock) with fair to good source rock potential. All three formations give a wide maturity range of vitrinite reflectance (VRo) and Tmax values, from immature to over-mature stage. Stratigraphically from youngest to oldest Miocene sequences, the Tmax increases with increasing VRo values. The dispersion of organic matter that requires high maturity and overburden of thick upper succession over Kalabakan Formation reflects a higher maturity stage than the Tanjong and Kapilit Formations. Pyrolysis results in Kapilit, Tanjong, and Kalabakan Formation has HI values to varies between 50 and 498 mg HC/g, 157–367 mg HC/g and 14–110 mg HC/g TOC respectively. The binary plot of HI versus Tmax supported by Py-GC pyrolysis marks that the Kapilit source rock is dominated by Type II-III kerogen, potentially generating immature to mature oil and gas prone. Tanjong Formation portrays a mature to late mature stage of Type III kerogen with a minor Type II kerogen capable of producing mixing of oil and gas prone, with mainly gas. The Kalabakan Formation shows a post-mature Type III and IV kerogen that generates gas or barren source rock. In terms of bulk kinetic evaluation, both Kapilit and Tanjong Formation are derived from heterogeneous organic matter. The projected petroleum temperature varies substantially due to the compositional variation. The onset of bulk petroleum generation in the Kapilit and Tanjong Formation occur at 112 °C - 128 °C and 127 °C - 142 °C respectively. The results are consistent with the maturity generated where the Tanjong has higher thermal maturity than Kapilit Formation due to stable aromatic Type III kerogen. Generally, all samples show great variability in thermal maturity and hydrocarbon generation potential, which that be influenced by the tectonism and development of sediments in the basin. The Early Miocene source rock yields post mature gas prone and continues to generate hydrocarbon that consists of mature oil and gas prone from younger source rocks.

A roadmap for the characterization of energy metabolism in human cardiomyocytes derived from induced pluripotent stem cells

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) are an increasingly employed model in cardiac research and drug discovery. As cellular metabolism plays an integral role in determining phenotype, the characterization of the metabolic profile of hiPSC-CM during maturation is crucial for their translational application. In this study we employ a combination of methods including extracellular flux, 13C-glucose enrichment and targeted metabolomics to characterize the metabolic profile of hiPSC-CM during their maturation in culture from 6 weeks, up to 12 weeks. Results show a progressive remodeling of pathways involved in energy metabolism and substrate utilization along with an increase in sarcomere regularity. The oxidative capacity of hiPSC-CM and particularly their ability to utilize fatty acids increased with time. In parallel, relative glucose oxidation was reduced while glutamine oxidation was maintained at similar levels. There was also evidence of increased coupling of glycolysis to mitochondrial respiration, and away from glycolytic branch pathways at later stages of maturation. The rate of glycolysis as assessed by lactate production was maintained at both stages but with significant alterations in proximal glycolytic enzymes such as hexokinase and phosphofructokinase. We observed a progressive maturation of mitochondrial oxidative capacity at comparable levels of mitochondrial content between these time-points with enhancement of mitochondrial network structure. These results show that the metabolic profile of hiPSC-CM is progressively restructured, recapitulating aspects of early post-natal heart development. This would be particularly important to consider when employing these cell model in studies where metabolism plays an important role.

Effects of Allium mongolicum Regel and its extracts on the quality of fermented mutton sausages.

The study aimed to evaluate the effects of Allium mongolicum Regel (AMR) and its water‐ and fat‐soluble extracts on the quality of fermented mutton sausages. Sausages were produced with mutton and fat. Four treatments: CO, without Allium mongolicum Regel and its extracts, used as control; AMR with Allium mongolicum Regel; AWE with water‐soluble extract of Allium mongolicum Regel; and AFE with liposoluble extract from Allium mongolicum Regel, were produced and analyzed for pH, water activity (a w), free amino acids, fatty acids, and volatiles were, respectively, in fermented mutton sausages during processing (0, 2, 5, and 7 days). The results showed that the pH values of the liposoluble extract from Allium mongolicum Regel (AFE), respectively, are lower than that of sample CO at the end of fermentation and ripening. The a w in all group of sausages significantly dropped to 0.88 at the end of ripening (Day 7). Adding Allium mongolicum Regel and its water‐soluble extract can improve the serine (SER) content of fermented mutton sausage. The contents of five essential amino acids (EAA) were added when adding Allium mongolicum Regel and its fat‐soluble extract. The total fatty acid (TFA) in the treatments increased during drying and ripening. The addition of Allium mongolicum Regel and its extract can increase the content of volatile flavor substances such as 3‐hydroxy‐2‐butanone, 3‐methylbutyraldehyde, hexanal, octanal, and nonanal at the later stage of maturity, so as to improve the flavor substances in fermented mutton sausage. Water‐soluble extract of Allium mongolicum Regel (AWE) and AFE treatments had more intense flavor at the end of ripening (Day 7). The flavor of fermented mutton sausage can be improved by adding Allium mongolicum Regel and its extracts into fermented mutton sausage.

Morphological and Ultrastructural Features of Formation of the Skin of Wheat (Triticum aestivum L.) Kernel.

The integumentary tissues of plant seeds protect the embryo (new sporophyte) forming in them from unfavorable external conditions; therefore, comprehensive knowledge about the structural and functional specificity of seed covers in various plants may be of both theoretical and practical interest. As a result of our study, additional data were obtained on the morphological and ultrastructural features of the formation of a multilayer skin of wheat (Triticum aestivum L.) kernel (caryopsis). The ultrastructure research analysis showed that differentiation of the pericarp and inner integument of the ovule leads to the formation of functionally different layers of the skin of mature wheat grain. Thus, the differentiation of exocarp and endocarp cells is accompanied by a significant thickening of the cell walls, which reliably protect the ovule from adverse external conditions. The cells of the two-layer inner integument of the ovule differentiate into cuticular and phenolic layers, which are critical for protecting daughter tissues from various pathogens. The epidermis of the nucellus turns into a layer of mucilage, which apparently helps to maintain the water balance of the seed. Morphological and ultrastructural data showed that the formation of the kernel’s skin occurs in coordination with the development of the embryo and endosperm up to the full maturity of the kernel. This is evidenced by the structure of the cytoplasm and nucleus, characteristic of metabolically active protoplasts of cells, which is observed in most integumentary layers at the late stages of maturation. This activity can also be confirmed by a significant increase in the thickness of the cell walls in the cells of two layers of the exocarp and in cross cells in comparison with the earlier stages. Based on these results, we came to the conclusion that the cells of a majority in the covering tissues of the wheat kernel during its ontogenesis are transformed into specialized layers of the skin by terminal differentiation.

Manipulation of Fatty Acid Metabolism Impairs Megakaryocyte Differentiation and Platelet Production

Background: Obesity is associated with an altered plasma lipid composition that impacts platelet activation, indicating that lipids directly affect platelet function and reactivity. However, very little is known about which essential lipids are important to enable platelet production from their precursors, megakaryocytes (MKs), and whether obesity influences lipid composition and consequently affects thrombopoiesis.Aim: We aimed to determine which lipids and associated pathways play a significant role in MK differentiation and platelet production in health and upon obesity. Our long-term goal is to determine if we can manipulate MK maturation and platelet production through lipid incorporation or inhibition.Methods: In order to determine the lipid profile of MKs through maturation, we performed an extensive lipidomics screen on primary MK progenitors, mature MKs, and platelets. Based on our findings, we then targeted de novo fatty acid (FA) synthesis in MKs to determine whether manipulation of this pathway attenuates MK differentiation and platelet formation. In parallel, we investigated megakaryo- and thrombopoiesis in an experimental setting of diet-induced obesity (DIO) in mice to examinate how altered lipid compositions within the plasma affect MK maturation.Results: Lipidomic data revealed increased polyunsaturated FA and plasmalogen content in the late stages of MKs maturation, suggesting that lipid composition is undergoing changes that may enable platelet production. To validate and extend these results, we inhibited multiple enzymes in de novo lipogenesis and FA synthesis. Using two different sources of primary murine hematopoietic stem cells (HSCs), we found that MK differentiation and maturation from HSCs was significantly decreased up to 60% after inhibition of acetyl-coA carboxylase (ACC) and 80% after fatty acid synthetase (FASN) inhibition, both enzymes from the de novo lipogenesis pathway. Moreover, we also found that MK differentiation and maturation were highly decreased (up to 70%) after the inhibition of acyl-coA synthetase (ACS). To further examine the role of fatty acids incorporation on platelet production, we next treated mature MKs with an ACS inhibitor to investigate the direct effect of FA incorporation on proplatelet formation; we observed a significant, multifoldreduction in proplatelet area. While dihydroceramides were altered in the lipidomic data, impairment of the de novo ceramide synthesis pathway did not affect either MK maturation or platelet production. Moreover, we observed an increased abundance of HSCs, myeloid cells, and MK progenitors in the bone marrow of DIO mice compared to control mice on a chow diet. This further supports an important role for lipids in megakaryopoiesis and suggests that differences in platelet reactivity during obesity may be caused by altered MK maturation and/or platelet production.Conclusions: Our results elucidate an important and previously unrecognized role for fatty acid synthesis in megakaryopoiesis and platelet production. The findings imply that an altered lipid content, as observed in patients with obesity, may not only impact platelet reactivity but also MK maturation and function. Consequently, platelets with an altered lipid content might originate from pathogenic MKs in obesity, which makes lipid-regulating proteins in MKs novel and viable therapeutic targets. DisclosuresMachlus: KEROS Therapeutics: Consultancy, Honoraria; STRM.BIO: Consultancy, Honoraria.

Pre-harvest sprouting in wheat: current status and future prospects

Pre- harvest sprouting (PHS) is one of the major constraint to wheat crop in areas experiencing high rainfall during the late maturity stages affecting both crop yields and quality of harvest in the world and north Eastern parts in India. This trait is polygenic and is affected by number of environmental factors. The available diversity for the trait is very limited and for improving tolerance newer sources of tolerance needs to be identified. The main cause of pre-harvest sprouting is the breakdown or lacking seed dormancy under humid and wet conditions and the starch in the germinated seeds is damaged due to alpha amylase activity. This review describes the factors affecting the pre-harvest sprouting tolerance, genes associated with PHS, physiological, biochemical and molecular mechanism involved in pre-harvest sprouting, screening for PHS and breeding approaches to develop improved tolerant genotypes.

Total mercury and methylmercury (MeHg) in braised and crude Boletus edulis carpophores during various developmental stages

We collected and processed Boletus edulis (King Bolete) carpophores grouped in four batches based on their developmental stage (button stage, young—white, large—white, and large—yellow). The study aimed, for the first time, to examine the B. edulis content and effect of braising and to estimate the intake of total mercury (THg) and methylmercury (MeHg) from a single meal based on whole (wet) weight (ww) and dry weight (dw). In braised carpophores, THg concentrations ranged from 0.2668 ± 0.0090 to 0.5434 ± 0.0071 mg kg−1 ww at different developmental stages, whereas crude products concentrations ranged from 0.1880 ± 0.0247 to 0.2929 ± 0.0030 mg kg−1 ww. The button stage crude carpophores were more highly contaminated with THg than at later stages of maturity, but MeHg levels were lower (p < 0.0001). On the other hand, braised button stage carpophores showed more MeHg than at later maturity stages. MeHg contributed at 1.9 ± 0.7% in THg in crude mushrooms and at 1.4 ± 0.3% in braised meals. The effect of braising was to increase the average THg and MeHg contents in fresh mushroom meals by 52 ± 31% and 53 ± 122% respectively, but a reduction of 40 ±14% and 40 ± 49% respectively was seen on a dw basis. The potential intakes of THg and MeHg from braised meals of B. edulis studied were small and considered safe.Graphical abstract

In vitro monitoring of HTR2A-positive neurons derived from human-induced pluripotent stem cells

The serotonin 5-HT2A receptor (5-HT2AR) has been receiving increasing attention because its genetic variants have been associated with a variety of neurological diseases. To elucidate the pathogenesis of the neurological diseases associated with 5-HT2AR gene (HTR2A) variants, we have previously established a protocol to induce HTR2A-expressing neurons from human-induced pluripotent stem cells (hiPSCs). Here, we investigated the maturation stages and electrophysiological properties of HTR2A-positive neurons induced from hiPSCs and constructed an HTR2A promoter-specific reporter lentivirus to label the neurons. We found that neuronal maturity increased over time and that HTR2A expression was induced at the late stage of neuronal maturation. Furthermore, we demonstrated successful labelling of the HTR2A-positive neurons, which had fluorescence and generated repetitive action potentials in response to depolarizing currents and an inward current during the application of TCB-2, a selective agonist of 5-HT2ARs, respectively. These results indicated that our in vitro model mimicked the in vivo dynamics of 5-HT2AR. Therefore, in vitro monitoring of the function of HTR2A-positive neurons induced from hiPSCs could help elucidate the pathophysiological mechanisms of neurological diseases associated with genetic variations of the HTR2A gene.

Revealing floral metabolite network in tuberose that underpins scent volatiles synthesis, storage and emission.

The role of central carbon metabolism in the synthesis and emission of scent volatiles in tuberose flowers was revealed through measurement of changes in transcripts and metabolites levels. Tuberose or Agave amica (Medikus) Thiede & Govaerts is a widely cultivated ornamental plant in several subtropical countries. Little is known about metabolite networking involved in biosynthesis of specialized metabolites utilizing primary metabolites. In this study, metabolite profiling and gene expression analyses were carried out from six stages of maturation throughout floral lifespan. Multivariate analysis indicated distinction between early and late maturation stages. Further, the roles of sugars viz. sucrose, glucose and fructose in synthesis, glycosylation and emission of floral scent volatiles were studied. Transcript levels of an ABC G family transporter (picked up from the floral transcriptome) was in synchronization with terpene volatiles emission during the anthesis stage. A diversion from phenylpropanoid/benzenoid to flavonoid metabolism was observed as flowers mature. Further, it was suggested that this metabolic shift could be mediated by isoforms of 4-Coumarate-CoA ligase along with Myb308 transcription factor. Maximum glycosylation of floral scent volatiles was shown to occur at the late mature stage when emission declined, facilitating both storage and export from the floral tissues. Thus, this study provides an insight into floral scent volatiles synthesis, storage and emission by measuring changes at transcripts and metabolites levels in tuberose throughout floral lifespan.

Milk from cows fed clover-rich silage compared with cows fed grass silage is higher in n-3 fatty acids

The present study investigated the effect of a high proportion of different forage species in the diet, parity, milking time, and days in milk (DIM) on milk fatty acid (FA) profile, and transfer efficiency of C18:2n-6, C18:3n-3, n-6, and n-3 in dairy cows. Swards with perennial ryegrass [early maturity stage (EPR) and late maturity stage (LPR)], festulolium, tall fescue (TF), red clover (RC), and white clover (WC) were cut in the primary growth, wilted, and ensiled without additives. Thirty-six Danish Holstein cows in an incomplete Latin square design were fed ad libitum with total mixed rations containing a high forage proportion (70% on dry matter basis). The total mixed rations differed only in forage source, which was either 1 of the 6 pure silages or a mixture of LPR silage with either RC or WC silage (50:50 on dry matter basis). Proportion of C18:2n-6 in milk FA was affected by diet, and RC and WC diets resulted in the highest proportion of C18:2n-6 in milk FA (21.6 and 21.8 g/kg of FA, respectively). The highest and lowest milk C18:3n-3 proportion was observed in WC and LPR, respectively. In addition, WC diet resulted in highest transfer efficiency of C18:3n-3 from feed to milk (12.2%) followed by RC diet (10.7%), whereas EPR diet resulted in the lowest transfer efficiency of C18:3n-3 (3.45%). The highest milk proportion of cis-9,trans-11 conjugated linoleic acid (CLA) was observed in cows fed TF (3.20 g/kg of FA), which was 23 to 64% higher than the proportion observed in the cows fed the other diets. The highest α-tocopherol concentration (µg/mL) in milk was observed in EPR (1.15), LPR (1.10), and festulolium (1.06). Primiparous cows showed higher proportion of cis-9,trans-11 CLA (2.63 g/kg of FA) than multiparous cows (2.21 g/kg of FA). Cows early in lactation had a higher proportion of long-chain FA in milk than cows later in lactation, as long-chain FA decreased with 0.184 g/kg of FA per DIM, whereas medium-chain FA increased with 0.181 g/kg of FA per DIM. Proportion of C18:2n-6 in milk from evening milking was higher than in milk from morning milking (16.7 vs. 15.8 g/kg of FA). In conclusion, the results showed that milk FA profile of cows was affected by forage source in the diet, and RC and WC increased the health-promoting FA components, particularly n-3, whereas the TF diet increased proportion of CLA isomers in milk. Proportion of CLA isomers in milk FA from primiparous cows was higher than in milk from multiparous cows. In addition, evening milk contained more FA originating from diets compared with morning milk.

Diurnal and seasonal CO2 exchange and yield of maize cropland under different irrigation treatments in semiarid Inner Mongolia

Different irrigation treatments in plants significantly influence CO2 emissions. This study investigated the net ecosystem CO2 exchange (NEE) and yield of maize cropland under different irrigation treatments to determine the optimal irrigation treatment at different maize growth stages. Different degrees of water deficit irrigation were carried out in four fields: full irrigation, 100% evapotranspiration (ET); moderate deficit irrigation, 65% ET; and severe deficit irrigation, 40% ET. Automated static and dynamic chambers were used to measure CO2 fluxes. We found that NEE showed a “V” -shaped trend during the day and slowly declined at night. The light response parameters were calculated using the rectangular hyperbola model, and the leaf area index accounted for 85% of the light use efficiency. In the late vegetative stage, severe deficit irrigation led to a reduction in CO2 emissions but significantly reduced the crop growth rate (p < 0.05). In the reproductive stage, full irrigation not only reduced CO2 emissions but also significantly increased the crop growth rate. In the maturation stage, moderate deficit irrigation reduced CO2 emissions, and the crop growth rate decreased compared with full irrigation, but the decrease was not significant (p > 0.05). Compared with full irrigation throughout the growth period, full irrigation in the reproductive stage and moderate deficit irrigation in the late vegetative and reproductive stages both increased the maize carbon sink capacity and light use efficiency at higher leaf area index, and the harvest index did not decrease significantly. However, inadequate irrigation in the reproductive stage or severe deficit irrigation in the late vegetative and maturation stages significantly reduced the maize harvest index. Thus, full irrigation during the reproductive stage, and moderate deficit irrigation during the late vegetative and reproductive stages were the optimal irrigation strategies for saving water, reducing CO2 emissions and ensuring a satisfactory maize yield.