Agricultural Research Corporation

The Amazon rainforest stores ~150–200 Pg of carbon and plays a central role in the global carbon cycle, yet it is highly vulnerable to land-use change, fire, and climate change, leaving its future carbon balance uncertain. Net Ecosystem Exchange (NEE) quantifies the balance between ecosystem carbon uptake and release, but long-term NEE assessments in Central Amazonia remain scarce due to limited observational coverage from eddy covariance towers and CO₂ profile measurements. The Amazon Tall Tower Observatory (ATTO; https://www.attoproject.org) helps overcome this limitation by providing more than a decade of continuous measurements and by capturing two extreme drought events (2015/2016 and 2023/2024). In this work, we analyzed 11 years of NEE estimates at ATTO (2014-2024) and we propose a methodology for selecting the friction velocity threshold (u*), based on the identification of a plateau in the NEE-u* relationship, where NEE becomes independent of increasing turbulence, and all periods with u below the threshold are filtered due to insufficient turbulence*. We estimate monthly u* thresholds ranging from 0.18 to 0.21 m s⁻¹. We found that, on average, the forest in the ATTO flux footprint generally acted as a net carbon sink. However, in years following severe droughts, such as 2016 and 2024, we detect a temporary reversal, with the ecosystem becoming a CO₂ source during the wet season. We also quantified the effect of environmental drivers modulating NEE across seasons. We find that higher air temperature reduces carbon uptake during the wet season. In contrast, soil moisture shows opposite relationships depending on season: during the dry season, increasing soil moisture (10 cm depth) reduces net carbon uptake, whereas during the wet season, increasing it enhances net carbon uptake. Our findings deliver critical observational evidence to refine model parameterizations of tropical carbon-water interactions and to reduce uncertainty in predictions of the Amazon carbon balance under future climate scenarios.

GABAA receptors (GABAA_AA) are ligand-gated chloride channels mediating fast and slow inhibitory signaling in the nervous system.-Subunit-containing receptors exhibit high GABA affinity, extrasynaptic localization and marked sensitivity to endogenous neurosteroids, generating tonic inhibitory currents that regulate baseline excitability in the CNS.Emerging evidence indicates that these receptors are also expressed in peripheral tissues, including the skin, retina, olfactory epithelium, gastrointestinal tract, kidney, immune cells and reproductive organs.They are notably absent in the heart, highlighting a selective role in sensory modulation.We hypothesize that -subunit-containing GABAA_AA receptors mediate local and systemic sensory inhibition through tonic, extrasynaptic signaling and neurosteroiddependent modulation.This network stabilizes neuronal and sensory activity, prevents hyperexcitability and may coordinate body-wide sensory responsiveness.Dysregulation of this system could contribute to disorders such as chronic pain, inflammatory skin disease, olfactory dysfunction and neuropsychiatric conditions.

The aim of this study was to examine the impact of the probiotics Saccharomyces cerevisiae (SC) and Pediococcus acidilactici (PA), as well as the prebiotic yeast cell wall extract (Cyberlindnera jadinii and S. cerevisiae) (YP), on the growth parameters, intestinal histomorphology, liver and gills normality, and gut microbiome of common carp (Cyprinus carpio L.). These feed supplements were subjected to a 60-day experimental period, during which 120 fish (26.4 ± 5.2 g) were distributed into four groups, with each group comprising 30 fish. The feed supplements were administered at a rate of 1 g/kg of body weight. Before the trial, the fish were acclimatized for two weeks, then injected with Passive Integrated Transponder (PIT) tags. The results showed that none of the feed supplements exhibited a significant effect (p > 0.05) on growth indices. In contrast, the villi length, villi width, muscular thickness, and crypt depth in the anterior, mid, and posterior intestine of the SC group exhibited significant (p < 0.05) improvements compared to the other groups. No alteration or abnormal growth were noticed in the gills and livers. The most dominant microbe genera in all groups, with abundances greater than 60% of the total, were Cetobacterium and Aeromonas. However, Polynucleobacter, Nordella, Mycoplasma, Romboutsia, and Staphylococcus species were present at lower abundances. The presence of Actinobacteria has been observed only in the intestine of fish that have been fed a diet supplemented with PA. It can be concluded that the tested probiotics and the yeast cell wall prebiotic have the potential to produce a remarkable improvement in intestinal morphology and a considerable change in the gut microbiome without notable effect on growth, livers, or gills of common carp.

IntroductionSorghum is a vital crop for food and nutritional security in drought-prone regions. However, the genetic potential of Sudanese Feterita landraces for stay-green (Stg) traits remains largely unexplored. MethodsThis study evaluated 133 Feterita genotypes using an integrated approach combining field phenotyping with KASP genotyping targeting the Stg3A and Stg3B QTLs. The genotypes were assessed during the 2022 season at the Gezira Research Station using an augmented design, and 14 morphological and agronomic traits were recorded for each genotype. Results and DiscussionSubstantial phenotypic variation was observed, with particularly high coefficients of variation for flowering stalks per plant (81.25%), senescence (49.09%), and grain number per panicle (43.33%). Genetic diversity analysis revealed moderate marker informativeness (GD = 0.407, I = 0.293, and PIC = 0.592). The AMOVA indicated weak population differentiation (Fst = 0.014), with 94% of the variation occurring within populations and substantial gene flow (Nm = 6.117). Pairwise Fst identified West Darfur and Blue Nile as genetically distinct, whereas Kordofan, White Nile, and Al-Gezira formed a cohesive cluster. Significant marker-trait associations were detected, including snpSB0054 (SGR1) with plant height and flowering time, snpSB0072 with panicle length, and snpSB0101 (SGR3) with grain number and seed yield. These findings highlight Feterita as a valuable reservoir of functional Stg alleles that influence senescence dynamics and drought-related yield traits. This study provides the first targeted characterization of stay-green alleles in Sudanese Feterita and lays the foundation for exploiting this germplasm in marker-assisted breeding to develop climate-resilient sorghum varieties in the future.

Capsule shattering in sesame is a major agronomic constraint that reduces yield stability and limits mechanized harvesting efficiency. To address this challenge, 200 genetically diverse sesame genotypes from Sudan were genotyped using genotyping-by-sequencing (GBS) and evaluated for three consecutive seasons under field conditions for shattering type (ST), type of capsule beak (TCB), and bicarpellate capsule shape (BS). The resulting phenotypic and genotypic data were integrated into a multi-model genome-wide association study (GWAS) framework (BLINK, FarmCPU, and MLMM) to elucidate the genetic architecture of capsule-shattering traits. Two marker-trait associations (MTAs) were consistently identified across the GWAS models, comprising Chr1_19419575 associated with the TCB and Chr2_15649330 linked to ST. Additional MTAs, including Chr8_31466064 for ST and Chr8_19392181 and Chr8_30292484 for TCB, were also detected in this study, further highlighting the complex genetic regulation of capsule traits. Allelic effect analysis further validated the functional role of key allelic variants at Chr2_15649330 and Chr8_31466064, demonstrating significant differences in shattering responses among genotypic subgroups. In silico functional enrichment analysis using a candidate gene approach identified 68 homologous genes associated with pod shattering in Brassica napus, of which FLZ3, RZF1, MKK5, and COR27 showed distinct expression patterns that correlated with shattering susceptibility during pod development. These results provide new insights into the genetic regulation of capsule shattering, providing valuable targets for marker-assisted selection and development of sesame cultivars with enhanced resistance to shattering.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00122-026-05151-7.

ABSTRACT The cultivation of okra [Abelmoschus esculentus (L.) Moench] has potential for expansion in Northeastern Brazil. However, irregular precipitation, associated with high evapotranspiration rates, is a limiting factor for agricultural development. In this context, the use of water-retaining polymers stands out as a promising alternative due to their capacity to retain water and ensure favorable conditions for plant growth. Thus, the present study aimed to evaluate the effects of a water-retaining polymer on the growth, production, and fruit quality of okra under different water replacement levels. The experiment was conducted in a greenhouse at CCTA/UFCG, Pombal Campus, PB, Brazil. The experimental design was a randomized block in a 5 x 4 factorial scheme, corresponding to five water replacement levels (40, 60, 80, 100, and 120% of the actual evapotranspiration - ETr) and four doses of a water-retaining polymer (0, 1.0, 2.0, and 3.0 g L-1), with three replications. A water replacement level of 80% ETr resulted in the greatest growth and production of okra cv. Carcará. Both deficit and excess water replacement caused growth inhibition and a decrease in the number of fruits. The application of the water-retaining polymer at a dose of 3.0 g L-1 had a beneficial effect on the growth, fresh mass, and mean diameter of the fruits, being indicated for okra cultivation in semiarid areas. Irrigation with 40% ETr combined with a 1.3 g L-1 of the water-retaining polymer increased the ascorbic acid content in the fruits of okra cv. Carcará.

ABSTRACT The limited availability of low-salinity water in the northeastern semi-arid region of Brazil is one of the main constraints to the expansion of irrigated agriculture. In this context, the objective of this study was to evaluate the effects of irrigation with saline water on the salinity tolerance of guava during the rootstock formation phase. The experimental design was a randomized complete block in a 2 x 5 factorial scheme, consisting of two guava genotypes (Crioula and cv. Paluma) and five levels of irrigation water electrical conductivity (ECw: 0.3, 1.2, 2.1, 3.0, and 3.9 dS m-1), with six replicates. Stem diameter, plant height, fresh biomass of leaves, stems, and roots, and the accumulation of dry biomass in leaves, stems, roots, and total biomass were measured, along with Dickson quality index, transpiration rate, stomatal conductance, CO2 assimilation rate, and the absolute and relative growth rates in plant height. Irrigation using water with electrical conductivity above 0.3 dS m-1 inhibited stem diameter growth, root dry biomass, leaf transpiration, relative growth rate in height, and Dickson quality index in guava seedlings. Among the genotypes, Crioula showed greater growth, photosynthetic activity, and Dickson quality index under saline water irrigation, indicating its potential for use as a rootstock under semi-arid conditions.

A social accounting matrix (SAM) is a square matrix that captures the circular flows of all economic transactions within a country at a given time. It serves as a reference database for calibrating single-country computable general equilibrium (CGE) models to analyse the economy-wide effects of policy changes and other external shocks. We developed a SAM for Burkina Faso for 2019, adopting a top-down approach, first developing a macro-SAM and further disaggregating it to obtain a micro-SAM. The SAM depicts land as a separate account, differentiates labour by skill level, and disaggregates agriculture and households by agroecological zones. The SAM comprises 91 accounts: 47 activities, 19 commodities, margins, five factors of production, 12 household groups, three tax accounts (sales, production, and income), government, enterprises, savings-investments, and the rest of the world. The SAM is freely accessible to support economy-wide analyses for Burkina Faso, specifically, analyses across agroecological zones.