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Modeling Climate Change Impacts on a Socioeconomically Vital Plant: The Case of Comanthera elegans (Goldenfoot Flower).
Full text linkComanthera elegans is a threatened, endemic species of the campos rupestres of the Espinhaço Mountain Range—a region rec- ognized as a biodiversity hotspot—and has great ecological and societal relevance to local traditional communities. Despite the importance of this species in these systems, the effects of climate change on its distribution remain relatively unknown. We employed the MaxEnt algorithm to model the current potential geographic distribution and the habitat suitability of this species under future climate scenarios to address this knowledge gap. We considered the SSP2- 4.5 and SSP5-8.5 scenarios, based on four global climate models (MRI-ESM2- 0, MIROC6, EC-Earth3-Veg, and CMCC-ESM2). The model exhibited high performance, indicating a strong affinity of the species for environments with high rainfall seasonality and mild temperatures. Our models predict a substantial loss of suitable habitat for C. elegans under scenarios of future climate change, particularly under high greenhouse gas emission scenarios, where high-suitability areas could be reduced by as much as 95% by 2060. Our results high- light the need for the implementation of conservation actions, including the expansion or creation of protected areas in climate refugia, alongside efforts to promote the development of cultivation techniques and regulations on harvesting practices, in order to mitigate the species' vulnerability to climate change
Viability of bionutrition on organic carbon and microbial metabolism in soil cultivated with Palmer mango.
Full text linkMango (Mangifera indica) cultivation holds economic importance and needs efficient nutrient management practices. Due to high costs of chemical fertilizers, sustainable alternatives, such as remineralizers and biofertilizers, are crucial for ensuring nutrition and maintaining soil quality. This study aimed to evaluate the effectiveness of remineralizers and biofertilizers, applied either alone or in combination with chemical fertilizers, on the content of organic carbon, humic substances, and microbial activity in the soil cultivated with ‘Palmer’ mango trees in the São Francisco Valley. Conducted from 2022 to 2024 in Petrolina, Pernambuco state, Brazil, the experiment employed a randomized block design with four treatments and five replicates. The treatments included: T1 (control), T2 (conventional management), T3 (remineralizers + biofertilizer), and T4 (50% chemical fertilizers + 50% remineralizers + biofertilizer), where T1 received no fertilizer application and T2 consisted of chemical fertilizers only. The evaluation encompassed the content of total organic carbon, humic substances, basal respiration, and microbial biomass. The collected data were subjected to analysis of variance to assess significant effects using the F test, with treatment comparisons conducted via Tukey’s test (p ≤ 0.05). Results indicated that all treatments enhanced contents of organic carbon and humic and fulvic acids in soil. Notably, microbial biomass showed efficiency degrading organic compounds when chemical fertilizers were applied. The combination of 50% chemical fertilizers with 50% remineralizers and biofertilizer (T4) yielded optimal results in terms of basal respiration and microbial biomass, establishing it an effective strategy to increase soil carbon, promote mango development, and reduce cost
Shade matters: heat stress alleviation in Gyr and Girolando cows through silvopastoral management in tropical conditions.
Full text linkSilvopastoral systems integrating tree cover into pasturelands offer promising strategies to mitigate heat stress in tropical livestock production. This study evaluated the effects of shade from Eucalyptus urograndis on thermal comfort indices in Gyr and Girolando dairy cattle in the Brazilian Cerrado. Forty-eight lactating cows (24 Gir, 24 Girolando) were monitored over two years in two contrasting environments: no shade (full sun) and shade (silvopasture). Thermal indices, including rectal and surface temperatures (measured via infrared thermography), respiration rates, and panting scores, were analyzed alongside environmental data, such as the Temperature-Humidity Index (THI). Cattle under shade consistently exhibited lower body temperatures, respiration rates, and panting scores, with significant differences amplified under heat stress conditions (THI > 74). Though both benefited from shade, Gyr cattle demonstrated better thermoregulatory responses than Girolando. Discriminant analysis accurately classified animals by system (> 92%) and breed (~ 71%) based on physiological traits. These results confirm that tree shade significantly enhances animal comfort in tropical pasture systems and supports the implementation of silvopastoral practices to improve dairy cattle welfare and resilience under climate stress
Development of a pressure-induced triploidy protocol and its effects on growth performance and fertility in tambaqui Colossoma macropomum (Cuvier, 1816).
Full text linkWe evaluated combinations of post-fertilization timing and shock duration using 8000 psi hydrostatic pressure to develop an efficient protocol for inducing triploidy in tambaqui Colossoma macropomum (Cuvier, 1816). Two trials were conducted. In the first (T1), newly fertilized eggs were exposed to 8000 psi for 120 s, initiated at 65 (T1.1), 95 (T1.2), 125 (T1.3), 155 (T1.4), 185 (T1.5), and 312 (T1.6) seconds post-fertilization (spf), with untreated eggs serving as control. All treatments produced high triploidization rates (>93%), but shocks applied at 65 and 95 spf (T1.1 and T1.2) resulted in higher fertilization (FGS >90%) and embryo survival indexes (ES >87%) than later treatments. Based on these results, a second trial (T2) optimized shock duration at 8000 psi: 65 spf for 60 s (T2.1) and 90 s (T2.2), and 95 spf for 60 s (T2.3) and 90 s (T2.4), with a control group. Triploidy rates were 56% in T2.1 and > 94% in T2.2–T2.4. FGS and ES were highest in T2.3 and T2.4. Growth evaluation of diploid (control; two ponds) and treated (combined T2 groups; two ponds) progenies reared in earthen ponds showed that triploids exhibited significantly greater body weight, height, and total and standard lengths during the first six months. Histological examination of 20-month-old progenies confirmed that triploids were infertile, whereas diploids reached sexual maturation. This study establishes a reliable 8000 psi pressure-shock protocol for producing sterile triploid C. macropomum, supporting its application in sustainable large-scale aquaculture
Genomic structure and selection history across Angus populations worldwide: insights from ROH, selection mapping, and functional analyses.
Full text linkAngus cattle, originally from Scotland, have been selectively bred for over 400 years, making them one of the most prominent beef breeds globally. Known for their adaptability, natural polled traits, and high-quality beef, Angus cattle have been intensively selected for growth, body size, and feed efficiency. This study investigates the genetic diversity, selection history, and key genomic regions across five Angus populations from the USA, Canada, Australia, Brazil, and Red Angus of America. Genomic data from 71,283 animals born between 1961 and 2024 were analyzed using Principal Component Analysis (PCA), phylogenetic tree construction, and Runs of Homozygosity (ROH), with the Generation Proxy Selection Mapping (GPSM) approach used to assess selection history. Functional annotation identified candidate genes and pathways related to selection. Our analysis revealed both similarities and differences across populations. The PCA and FST metrics showed minimal differentiation between the American, Canadian, Australian, and Brazilian populations, with greater differentiation observed in the Red Angus population. The ROH analysis revealed that the Brazilian population had the highest number of ROHs. The ROH islands identified on BTA8 and BTA13 in the American and Australian populations were linked to traits like body weight, marbling, and tenderness. The GPSM identified significant markers associated with body weight and growth in all populations, reflecting ongoing selection pressures. This study highlights the potential of genomics to improve our understanding of Angus cattle’s genetic architecture and selection history. It underscores the feasibility of integrating global populations for more accurate genomic evaluations, enhancing genetic predictions, and supporting sustainable beef production worldwide
Inbreeding depression affecting stayability in Italian Holstein cows.
Full text linkAdvances in selection and reproduction methods, particularly the implementation of genomic evaluations alongside assisted reproductive technologies, have substantially enhanced productivity and efficiency, notably within specialized dairy cattle populations. Nevertheless, the widespread use of a limited number of elite sires and dams has also led to increased levels of inbreeding, posing a risk to animal performance in production, reproduction, and functional longevity. The objective of this study was to evaluate the effect of inbreeding on stayability in the Italian Holstein population. Stayability, defined as the ability of cows to remain productive in the herd from one parity to another, was assessed across 5 periods: STAY12, from parity 1 to 2; STAY23, from parity 2 to 3; STAY34, from parity 3 to 4; STAY13, from parity 1 to 3; and STAY14, from parity 1 to 4. Individual inbreeding coefficients were estimated using 3 methods: pedigree information, diagonal elements of the genomic relationship matrix, and the proportion of the total length of runs of homozygosity (ROH) segments relative to the total autosomal genome covered by SNPs. Furthermore, different ROH length classes were evaluated separately to distinguish between the effects of recent and ancient inbreeding. Two datasets were extracted from the breeders’ association database with no interference in the herds’ usual management: one including both genotyped and nongenotyped individuals and another with only genotyped animals. The first, comprising 828,056 cows, was used to assess pedigree-measured inbreeding depression in the Italian Holstein population. The second, including 48,833 genotyped cows, was used to compare inbreeding measures. The effect of inbreeding was estimated as best linear unbiased estimates on the liability scale within a Bayesian framework. In the stayability analysis, milk yield level relative to contemporary group was included as an additional fixed effect to account for its influence. Estimates were converted to the probability scale, using a cumulative distribution function, and then used to compare models and assess survival probabilities according to varying levels of inbreeding. Increased inbreeding consistently resulted in decreased stayability. The magnitude of inbreeding depression was greater for traits involving cumulative periods, such as STAY13 and STAY14. The expected variation in stayability resulting from a 1-unit increase in the pedigree inbreeding coefficients (FPED), ranged from −0.06% to −0.44%, depending on the model and trait. Models using genomic inbreeding captured larger effects of inbreeding depression. In these cases, the expected variation in stayability ranged from −0.22% to −1.60% per 1-unit increase in FPED. Inbreeding estimated from the sum of ROH segments longer than 2 Mb were associated with reduced stayability, whereas shorter segments were not. This suggests that recent inbreeding contributes to inbreeding depression on this trait, whereas ancient inbreeding does not. It should be noted that part of the observed inbreeding depression may be attributable to voluntary culling related to the production level of cows within their herds. Thus, in a selection index that includes milk yield and penalizes future inbreeding, stayability should preferably be analyzed using a model that incorporates production level as a fixed effect
Soybean yield potencial in petric plinthosols: climate and economic interactions.
Full text linkABSTRACT: Soybean production in central Brazil predominantly occurs on ferralsols. However, increasing global demand has driven expansion into marginal areas with less suitable soils, particularly petric plinthosols. These soils present significant agronomic challenges, especially their heightened vulnerability to climatic variability. Nevertheless, some regions with petric plinthosols, such as parts of Tocantins state, have achieved surprisingly high soybean yields. Despite this production potential, research on soybean cultivation in petric plinthosols are still limited. Our study addresses this knowledge gap by evaluating how environmental conditions and management practices, particularly sowing dates, affect soybean yields in petric plinthosols compared to ferralsols. We also developed economic indicators to support sustainable production decisions. The results demonstrated that while high yields are achievable in petric plinthosols, these soils exhibit greater climate sensitivity than ferralsols. Environmental factor such as air humidity, mainly in the reproductive phase, is a limiting factor for higher yields. Notably, our economic analysis revealed that cost management impacts profitability more substantially than yield improvements, even under unfavourable conditions. This finding suggests that strategic farm management could make petric plinthosol cultivation economically viable despite their agronomic constraints
SWAT model and drought indices: a systematic review of progress, challenges and opportunities.
Full text linkDrought is a natural phenomenon that has significant environmental and socioeconomic impacts. Drought indices are fundamental tools for quantifying and monitoring this hazard. In regions where ground data are scarce, hydrological modeling offers an alternative for drought monitoring and developing early warning systems. This study conducted a systematic literature review, following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) protocol, to analyze the integrated application of the SWAT (Soil and Water Assessment Tool) model and the use of drought indices. A total of 803 articles published between 2011 and 2025 were identified in the Scopus and Web of Science databases, of which 115 met the eligibility criteria and were included in the review. The analysis revealed significant advances in the use of SWAT for drought monitoring and prediction, including the development of indices and forecasting systems. However, notable gaps remain, particularly the limited use of advanced statistical methodologies (e.g., machine learning and non-stationarity analyses) and the lack of harmonization and standardization across indices. Overall, this review establishes SWAT as a robust tool to support drought management strategies, while highlighting substantial untapped potential. Future research addressing these gaps is essential to strengthen drought indices and improve operational warning systems
Functional herkogamy and pollination biology in Passiflora cincinnata Mast.
Full text linkFruit production in passionfruit species is primarily associated with cross-pollination, but the role of herkogamy, the spatial separation between stigmas and anthers, in reproductive success remains poorly understood. This study evaluated the influence of style deflexion on fruit set in Passiflora cincinnata Mast., a native species of the Brazilian Caatinga, using accessions conserved in a Passionfruit Germplasm Bank (BAG). Flowers were classified into three morphotypes: stigmas positioned below the anthers, stigmas aligned with the anthers, and stigmas positioned above the anthers. Pollen viability was evaluated using subsamples of randomly selected flowers within each floral morphotype. Across all accessions, 41.75% of flowers displayed stigma below the anthers, 26.32% exhibited aligned the stigma with the anthers, and 31.93% had stigma positioned above, with pollen viability consistently high (96.4–96.7%). Flowers in which stigmas were located below the anthers (negative deflexion) showed the highest fruit set under hand pollination (73.3%), whereas flowers with aligned or elevated stigmas produced only a few fruits (4.7%) in heterotypic crosses. These findings demonstrated that herkogamy strongly shapes reproductive outcomes in P. cincinnata. Integrating this knowledge into germplasm management, conservation, and breeding initiatives will be essential for improving passionfruit cultivation and promoting sustainable agricultural practices in semiarid ecosystems
The challenges of family farming from the perspective of third-generation public policies for rural development in Brazil.
Full text linkThe article in question aims to analyze the scenarios of third-generation public policies for family farming and their challenges. The methodology includes a systematic literature review and documentary research. The main obstacles identified include limited access to credit, inadequate infrastructure, and a lack of information about programs among a significant portion of the population. The results highlight the importance of effective public policies to promote actions for productive inclusion and sustainable rural development, integrating economic, social, and environmental aspects