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Bioactive peptides in preterm human milk: Impact of maternal characteristics and their association to neonatal outcomes

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Bioactive peptides in preterm human milk: Impact of maternal characteristics and their association to neonatal outcomes

Hormone content of very preterm human milk is partially determined by maternal factors most of them regarding metabolic health and obstetric characteristics. Human milk concentration impacts on growth and development of preterm infants during their stay in the neonatal unit.


Abstract

Human milk adipokines in term babies seem partially determined by maternal factors and affect infant's development. We aimed to describe bioactive peptide concentration in very preterm human milk and associations to maternal characteristics and postnatal growth. Mothers delivering ≤32 weeks of gestation and their infant/s were recruited. At 4 weeks of lactation, an aliquot of 24-h-pooled milk was collected for exclusively breastfeeding dyads. Insulin, leptin, adiponectin, and milk fat globule epidermal growth factor-8 (MFG-E8) were measured by enzyme-linked immunoabsorbent assay in skimmed milk. One hundred mothers (28.8 ± 2.3 weeks at delivery) provided a milk sample. Milk insulin was related to gestational age, pre-pregnancy body mass index (BMI), and galactagogue treatment (final model: adjusted R 2: 0.330, p < 0.0001; adjusted β coefficients: galactagogue treatment: 0.348, p 0.001; pre-pregnancy BMI: 0.274, p 0.009; gestational age: −0.290, p 0.007). Adiponectin was higher in mothers with gestational diabetes (30.7 ± 6.5 vs. 24.8 ± 8 ng/mL, p 0.044). Leptin was associated with pre-pregnancy BMI (Spearman's ρ: 0.648, p < 0.0001) and MFG-E8 to presence of labor and multiple pregnancy (final linear regression model, R 2: 0.073, p 0.028, adjusted β coefficients: presence of labor −0.229, p 0.050; twins: −0.192, p 0.099). Milk adiponectin was associated with a greater decrease in length z-scores from birth to 28 days (Pearson's r: −0.225, p 0.032) and to discharge (Pearson's r: −0.290, p 0.003). Milk MFG-E8 was lower in milk of mothers whose babies experienced late-onset sepsis (13.3 ± 5.8 vs. 16.8 ± 6.3 μg/mL, p 0.023). Adipokines levels in preterm human milk are partially related to maternal metabolic status. Milk peptide concentration associates with early neonatal growth trajectories.

Characterization of sugarcane mosaic virus from Cymbopogon spp. plants in Brazil

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Abstract

In April 2022, virus-like symptoms were observed in a Cymbopogon spp. plant grown in the backyard of a house and in Java citronella (C. winterianus) plants in a flower shop in Piracicaba, São Paulo State, Brazil. In April 2023, ca. 700,000 Ceylon citronella (C. nardus) plants showing symptoms of mosaic were observed in a field crop in Dois Corrégos (SP). Evidence for a possible potyvirus infection was revealed by electron microscopy and confirmed by molecular assays. Nucleotide sequencing of amplicons from RT-PCR identified the potyvirus infecting a Cymbopogon spp. plant, Java and Ceylon citronella as sugarcane mosaic virus (SCMV, genus Potyvirus). Phylogenetic analysis of the coat protein gene indicated that the SCMV isolates from Cymbopogon (C1), Java (JC1), and Ceylon citronella (CC) belong to the clade of SCMV from sugarcane. The C1 isolate, and an isolate from sugarcane (SCMV-SU) (control) were mechanically transmitted to Java citronella, sorghum, sugarcane and maize plants. Aphis gossypii transmitted the C1 and SU isolates to Java citronella plants, while Melanaphis sacchari transmitted only the SU isolate to Java citronella plants. This is the first molecular characterization of SCMV from Cymbopogon spp. plants.

Meloidogyne arenaria infecting Matricaria chamomilla in Brazil

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Abstract

Plants of Matricaria chamomilla L. (Asteraceae), well-known medicinal species, showing root galls, were collected in Pelotas, state of Rio Grande do Sul (Brazil). Based on morphological (perineal patterns and males), morphometric (males) and esterase phenotypes (Est A2), we identified the infecting nematode as the root-knot nematode M. arenaria. Under greenhouse conditions, four M. chamomilla plants were inoculated with about 1000 specimens obtained from the isolate. We observed about 207 ± 72 nematodes g−1 of roots, confirming its pathogenicity. To the best of our knowledge, this is the first record of M. arenaria parasitizing M. chamomilla in Brazil and elsewhere.

Evaluation of native isolates of Trichoderma spp. for controlling potato late blight caused by Phytophthora infestans in Nepal

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Abstract

Late blight, caused by Phytophthora infestans, is the most devastating disease of potato worldwide that can cause up to 100% crop loss under disease conducive conditions. The present study was carried out to evaluate and identify effective Trichoderma isolates against the disease. Thirty-nine isolates of Trichoderma spp. isolated at Nepal Plant Disease and Agro Associates (NPDA), Kathmandu from Likhu areas of Nuwakot, Nepal were screened against P. infestans in detached leaf assay for their efficacy in reducing the lesion size of late blight. Fifteen isolates significantly reduced lesion size by 19%–46% compared with the control (water spray). Of them, top 10 isolates along with Sanjeevni (T. viride), a commercial product were tested in field experiments under natural epiphytotic conditions at Thansing and Dhikure of Likhu Rural Municipality in 2020–2021 and 2022–2023 crop years, respectively. The Trichoderma isolates significantly (p < .001) increased plant growth, tuber yield and reduced disease severity in both years. In 2020–2021, isolates, TL1-2A, TL4-81A and TL5-21A reduced disease severity by 37.3%, 37.2% and 30.4%, respectively. The isolate TL1-2A also significantly increased plant height, ground coverage and tuber yield by 41.2%, 30.3% and 72.3%, respectively compared with the control (water spray). In 2022–2023, TL1-2A reduced disease severity by 40.2% and increased tuber yield by 46.4%. Other isolates, though significantly different from control, did not have satisfactory effect on disease control and tuber yield. In both years, the isolate TL1-2A significantly reduced the disease, and increased plant growth and tuber yield. Thus, TL1-2A isolate can be a potential candidate as a biocontrol agent for the integrated management of potato late blight in Nepal.

Approaching 25 years of progress towards Fusarium head blight resistance in southern soft red winter wheat (Triticum aestivum L.)

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Abstract

Tremendous progress has been made in variety development and host plant resistance to mitigate the impact of Fusarium head blight (FHB) since the disease manifested in the southeastern United States in the early 2000s. Much of this improvement was made possible through the establishment of and recurring support from the US Wheat & Barley Scab Initiative (USWBSI). Since its inception in 1997, the USWBSI has enabled land-grant institutions to make advances in reducing the annual threat of devastating FHB epidemics. A coordinated field phenotyping effort for annual germplasm screening has become a staple tool for selection in public and private soft red winter wheat (SRWW) breeding programmes. Dedicated efforts of many SRWW breeders to identify and utilize resistance genes from both native and exotic sources provided a strong foundation for improvement. In recent years, implementation of genomics-enabled breeding has further accelerated genetic gains in FHB resistance. This article reflects on the improvement of FHB resistance in southern SRWW and contextualizes the monumental progress made by collaborative, persistent, and good old-fashioned cultivar development.

Genotypic stability in root system architecture and aboveground biomass revealed diverse adaptability of peanut (Arachis hypogaea L.) to moderate water deficit

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Abstract

Many crop species, including cultivated peanut (Arachis hypogaea L.), modify their above- and below-ground growth to cope with water deficit stress. This acclimation to water deficit often triggers a biomass partitioning shift—allocating more biomass to the roots, to increase the accessibility of roots to water resources. However, additional carbon partitioning to roots may not always translate into increased water use and maintenance of aboveground biomass (ABM) and yield. Therefore, selecting an efficient root system architecture (RSA) should aim to sustain a high ABM production under a water deficit scenario. To better understand the associations of above and belowground biomass partitioning under moderate water deficit, this study evaluated the genotypic stability of 40 peanut genotypes in ABM and RSA in greenhouse experiments and further assessed genotypic differences in 4 site-year field experiments. Our results suggested that higher ABM-producing genotypes generally had high plasticity when subjected to water deficit whereas the low ABM-producing genotypes had relatively high stability. Hierarchical clustering analysis further revealed that genotypes with a high root-to-shoot ratio potentially had increased genotypic stability in ABM underwater deficit. Interestingly, genotypes that maintained the highest ABM underwater deficit did not have the highest total root biomass and length. Instead, these genotypes had the highest root length in the top layer of soil (0–0.3 m) and relatively fewer roots in the deeper layer of soil (0.3–1 m). Greenhouse-screened stable genotypes exhibited minimal yield reduction when subjected to mid-season water deficit in some of the field validation experiments, but it also happened to some plastic genotypes, indicating that further validation of controlled environment screenings for genotypic water-deficit tolerance in the field is necessary.

RALF‐like peptide improves the colonization of endophytic Colletotrichum tofieldiae through interacting with plant receptor‐like kinase

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RALF-like peptide improves the colonization of endophytic Colletotrichum tofieldiae through interacting with plant receptor-like kinase

Endophytic Colletotrichum tofieldiae harbours RALF homologues to regulate symbiotic signals and promote hyphae colonization through interacting with FERONIA encoded by plant.


Abstract

Endophytes can colonize a host plant without inducing obvious disease symptoms. Elicitors from endophytes may play important roles in balancing endophyte colonization. We identified a novel endophytic elicitor from Colletotrichum tofieldiae, CtRALF, that has structural and functional characteristics similar to those of rapid alkalinization factor (RALF) peptides in Arabidopsis thaliana. We found that CtRALF can directly interact with the host plant receptor-like kinase FERONIA (FER). The colonization of FER mutant plants by hyphae of C. tofieldiae was obviously reduced compared with that on wild-type plants. Furthermore, the interaction of CtRALF with FER regulated symbiotic signals by triggering calcium waves, inhibiting reactive oxygen species bursts, increasing mitogen-activated protein kinase phosphorylation and reducing the stabilization of MYC2. Collectively, these results suggested that the RALF homologue of endophytes may improve their symbiosis by interacting with host plant-encoded FER.

Deciphering the inheritance of fertility restoration and influence of environmental factors on maldandi source of male sterility in rabi sorghum [Sorghum bicolor (L.) Moench]

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Abstract

This study aimed to investigate the inheritance pattern of fertility restoration in hybrids resulting from crosses between a male sterile line (M31-2A), a maldandi cytoplasm, and two promising restorers (DSMR-4 and DSMR-8). The evaluation of hybrids was conducted in two sets of experiments, including the F2, BC1F1 and F2, F3 generations. The segregation pattern was analysed in the F2 and BC1F1 generations, resulting in a 54:10 ratio of fertile to sterile plants and a 1:1 ratio of fertile to sterile plants, respectively. This indicated the involvement of three genes, at least two of which must be in a dominant condition for restoration to occur, acting in a duplicate complementary manner. In the F3 generation, both crosses were grown to confirm the stability of restorers, and they segregated in the ratio of 10 true-breeding families and 44 segregating families, which was consistent with the F2 ratio. Additionally, this study observed the influence of rainfall on the partial restoration pattern over seasons, as restorer genes are up or down-regulated depending on the availability of water.