Search Results (263)

Climate extremes threaten the resilience of Eucalyptus plantations, yet hybridization with drought-tolerant species may enhance stress tolerance. This study analyzed xylem anatomical and functional drought responses in commercial Eucalyptus grandis (GG) clones and hybrids: E. grandis × camaldulensis (GC), E. grandis × tereticornis (GT), and E. grandis × urophylla (GU1, GU2). We evaluated vessel traits (water transport), fibers (mechanical support), and wood density (D) in stems and branches. Theoretical stem hydraulic conductivity (k_Stheo), vessel lumen fraction (F), vessel composition (S), and associations with previous hydraulic and growth data were assessed. While general drought responses occurred, GC had the most distinct xylem profile. This may explain it having the highest performance in different irrigation conditions. Red gum hybrids (GC, GT) maintained k_Stheo under drought, with stable F and a narrower vessel size, especially in branches. Conversely, GG and GU2 reduced F and S; and stem k_Stheo declined for a similar F in these clones, indicating vascular reconfiguration aligning the stem with the branch xylem. Almost all clones increased D under drought in any organ, with the highest increase in red gum hybrids. These results reveal diverse anatomical adjustments to drought among clones, partially explaining their growth responses. Full article

Deforestation driven by plantations, such as Pinus patula Schiede ex Schltdl. et Cham., is a major cause of biodiversity and functional loss in tropical ecosystems. We assessed the diversity and composition of lichens and bryophytes in four size categories of pine cones, small (3–5 cm), medium (5.1–8 cm), large (8.1–10 cm), and very large (10.1–13 cm), with a total of 150 pine cones examined, where the occurrence and cover of lichen and bryophyte species were recorded. Identification keys based on morpho-anatomical features were used to identify lichens and bryophytes. In addition, for lichens, secondary metabolites were tested using spot reactions with potassium hydroxide, commercial bleach, and Lugol’s solution, and by examining the specimens under ultraviolet light. To evaluate the effect of pine cone size on species richness, the Kruskal–Wallis test was conducted, and species composition among cones sizes was compared using multivariate analysis. A total of 48 taxa were recorded on cones, including 41 lichens and 7 bryophytes. A total of 39 species were found on very large cones, 37 species on large cones, 35 species on medium cones, and 24 species on small cones. This is comparable to the diversity found in epiphytic communities of pine plantations. Species composition was influenced by pine cone size, differing from small in comparison with very large ones. The PERMANOVA analyses revealed that lichen and bryophyte composition varied significantly among the pine cone categories, explaining 21% of the variance. Very large cones with specific characteristics harbored different communities than those on small pine cones. The presence of lichen and bryophyte species on the pine cones from managed Ecuadorian P. patula plantations may serve as refugia for the conservation of biodiversity. Pine cones and their scales (which range from 102 to 210 per cone) may facilitate colonization of new areas by dispersal agents such as birds and rodents. The scales often harbor lichen and bryophyte propagules as well as intact thalli, which can be effectively dispersed, when the cones are moved. The prolonged presence of pine cones in the environment further enhances their role as possible dispersal substrates over extended periods. To our knowledge, this is the first study worldwide to examine pine cones as substrates for lichens and bryophytes, providing novel insights into their potential role as microhabitats within P. patula plantations and forest landscapes across both temperate and tropical zones. Full article

The effects of changes in China’s final demand structure on its forestry sector and associated supply chains have not been thoroughly examined. This study aims to provide a detailed analysis of the quantitative relationships and underlying mechanisms between these interactive changes. Using China’s 153-sector input–output tables from the National Bureau of Statistics and applying a Leontief-based input–output model, we conducted scenario simulations through three distinct schemes, generating both quantitative and qualitative results. Our findings indicate that (1) For China’s forestry sector and its entire value chain to thrive, policymakers should boost consumer demand. This can better stimulate the development of forestry and the “agriculture-forestry-animal husbandry-fishery services” sector and related service industries; (2) Increased investment demand effectively stimulates the development of tertiary industries and secondary industries within the forestry supply chain and boosts the demand and production of intermediate products; (3) Changes in net exports have a significant impact on forestry and the forestry industry chain. To reduce dependence on foreign timber resources, China should strategically expand commercial plantation development; (4) Regarding intermediate product production, investment has a more pronounced effect on increasing total volume compared to consumption. Additionally, the Sino–US tariff disputes negatively impact the forestry industries of both countries. China needs to accelerate import substitution strategies for timber products, adjust international trade markets, and expand domestic consumption and investment to ensure the healthy and stable development of its forestry sector. Full article

In wet subtropical environments, perennial groundcovers are common in horticultural plantations to protect the soil from erosion. However, there has been little investigation into whether seeding annual cover crops into the perennial groundcovers provides additional soil services including carbon and nutrient cycling in these systems. To investigate this, farmer participatory field trials were conducted in commercial avocado, macadamia, and coffee plantations in the wet Australian subtropics. Cover crops were direct-seeded into existing inter-row groundcovers in winter (cool season cover crops), and into the same plots the following summer (warm season cover crops). Inter-row biomass was quantified at the end of winter and summer in the control (no cover crop) and cover crops treatments. Soil carbon and nutrient cycling parameters including hot water extractable carbon, water soluble carbon, autoclavable citrate-extractable protein and soil enzyme activities were quantified every two months from early spring (September) 2021 to late autumn (May) 2022. Seeded cover crops produced 500 to 800 kg ha⁻¹ more total inter-row biomass over winter at the avocado coffee sites, and 3000 kg ha⁻¹ biomass in summer at the coffee site. However, they had no effect on biomass production in either season at the macadamia site. Soil functional parameters changed with season (i.e., time of sampling), with few significant effects of cover crop treatments on soil function parameters across the three sits. Growing a highly productive annual summer cover crop at the coffee site led to suppression and death of perennial groundcovers, exposing bare soil in the inter-row by 3 weeks after termination of the summer cover crop. Annual cover crops seeded into existing perennial groundcovers in tree crop systems had few significant impacts on soil biological function over the 12-month period, and their integration needs careful management to avoid investment losses and exacerbating the risk of soil erosion on sloping lands in the wet subtropics. Full article

Water scarcity is a key constraint for commercial Eucalyptus plantations, particularly given the increasing frequency of droughts driven by climate change. This study assessed annual transpiration (Tr) and water use efficiency (WUE) across eight genotypes subjected to contrasting irrigation regimes (WR). A split-plot design was implemented, comprising two irrigation levels: high (maintained above 75% of field capacity) and low (approximately 25% above the permanent wilting point). The genotypes included Eucalyptus globulus (EgH, EgL), E. nitens × globulus (EngH, EngL), E. nitens (En), E. camaldulensis × globulus (Ecg), E. badjensis (Eb), and E. smithii (Es). Between stand ages of 7 and 9 years (2020–2023), we measured current annual increment (CAI), leaf area index (LAI), Tr, and WUE. Under high WR, CAI ranged from 8 to 36 m³ ha⁻¹ yr⁻¹, Tr from 520 to 910 mm yr⁻¹, and WUE from 0.7 to 2.9 kg m⁻³. Low irrigation reduced CAI by 5–25% and Tr by 10–35%, while WUE responses varied across genotypes, ranging from a 12% decrease to a 48% increase. Based on their functional responses, genotypes were grouped as follows: (i) stable performers (Es, Ecg, Eb) exhibited high WUE and consistent Tr under both WR; (ii) partially plastic genotypes (EgH, EngH) combined moderate reductions in Tr with improved WUE; and (iii) water-sensitive genotypes (EgL, EngL, En) showed substantial declines in Tr alongside variable WUE gains. These findings underscore the importance of selecting genotypes with adaptive water-use traits to improve the resilience and long-term sustainability of Eucalyptus plantations in Mediterranean environments. Full article

Strawberry (Fragaria × ananassa), a nutrient-dense fruit with significant economic value in commercial cultivation, faces critical detection challenges in automated harvesting due to complex growth conditions such as foliage occlusion and variable illumination. To address these limitations, this study proposes Ripe-Detection, a novel lightweight object detection framework integrating three key innovations: a PEDblock detection head architecture with depth-adaptive feature learning capability, an ADown downsampling method for enhanced detail perception with reduced computational overhead, and BiFPN-based hierarchical feature fusion with learnable weighting mechanisms. Developed using a purpose-built dataset of 1021 annotated strawberry images (Fragaria × ananassa ‘Red Face’ and ‘Sachinoka’ varieties) from Changchun Xiaohongmao Plantation and augmented through targeted strategies to enhance model robustness, the framework demonstrates superior performance over existing lightweight detectors, achieving mAP50 improvements of 13.0%, 9.2%, and 3.9% against YOLOv7-tiny, YOLOv10n, and YOLOv11n, respectively. Remarkably, the architecture attains 96.4% mAP50 with only 1.3M parameters (57% reduction from baseline) and 4.4 GFLOPs (46% lower computation), simultaneously enhancing accuracy while significantly reducing resource requirements, thereby providing a robust technical foundation for automated ripeness assessment and precision harvesting in agricultural robotics. Full article

The sterol demethylation inhibitors (DMIs) are among the most widely used fungicides for controlling black Sigatoka (Mycosphaerella fijiensis) and yellow Sigatoka (Mycosphaerella musicola) in banana plantations in Brazil. Black Sigatoka is considered more important due to causing yield losses of up to 100% in commercial banana crops under predisposing conditions. In contrast, yellow Sigatoka is important due to its widespread occurrence in the country. This study aimed to determine the current sensitivity levels of Mf and Mm populations to DMI fungicides belonging to the chemical group of triazoles. Populations of both species were sampled from commercial banana plantations in Registro, Vale do Ribeira, São Paulo (SP), Ilha Solteira, Northwestern SP, and Janaúba, Northern Minas Gerais, and were further characterized phenotypically. Additionally, allelic variation in the CYP51 gene was analyzed in populations of these pathogens to identify and characterize major mutations and/or mechanisms potentially associated with resistance. Sensitivity to the triazoles propiconazole and tebuconazole was determined by calculating the 50% inhibitory concentration of mycelial growth (EC₅₀) based on dose–response curves ranging from 0 to 5 µg mL⁻¹. Variation in sensitivity to fungicides was evident with all nine Mf isolates showing moderate resistance levels to both propiconazole or tebuconazole, while 11 out of 42 Mm strains tested showed low to moderate levels of resistance to these triazoles. Mutations leading to CYP51 substitutions Y136F, Y461N/H, and Y463D in Mm and Y461D, G462D, and Y463D in Mf were associated with low or moderate levels of resistance to the triazoles. Interestingly, Y461H have not been reported before in Mm or Mf populations, and this alteration was found in combination with V106D and A446S. More complex CYP51 variants and CYP51 promoter inserts associated with upregulation of the target protein were not detected and can explain the absence of highly DMI-resistant strains in Brazil. Disease management programs that minimize reliance on fungicide sprays containing triazoles will be needed to slow down the further evolution and spread of novel CYP51 variants in Mf and Mm populations in Brazil. Full article

Melina (Gmelina arborea Roxb.) is a tree native to Asia, whose timber is not utilized in that region for a variety of reasons. However, the tree’s fast growth and extensive range of applications have increased its acceptance in other world’regions. G. arborea was introduced to Mexico in 1971, and it is currently the fifth most utilized forest species in commercial forest plantations (CFPs). However, its genetic diversity has not been evaluated in Mexico. The objective of this research was to investigate the genetic variability of Melina in Mexico using molecular markers. This investigation was undertaken to acquire valuable insights for the implementation of effective improvement strategies. A total of 85 Melina samples were collected from various locations in southeastern Mexico between 2017 and 2022. Genetic fingerprints were obtained using ten simple primer amplification reactions (SPARs): five Directed Amplification of Minisatellite DNA regions (DAMD), and five Inter-Simple Sequence Repeats (ISSRs). The polymorphic information content (PIC) was 0.940 and 0.950 for the DAMD and ISSR, respectively, and the similarity coefficients ranged from 0.12 to 0.88, indicating a high degree of polymorphism in the species under investigation. This is the first attempt to ascertain the genetic variability of Gmelina arborea in Mexico. Full article

Rhizospheric fungi are emerging as a critical research component in dragon fruit (Hylocereus spp.) production systems. Introducing beneficial non-native fungi is increasingly common due to their positive effects on plant growth, yield, and pathogen suppression. However, this practice may disrupt soil microbial communities, and commercial isolates often show limited adaptation to local conditions. This study aimed to identify native beneficial soil fungi associated with dragon fruit cultivation on the Ecuadorian coast and evaluate their effect on commercial production. Fungal isolates from four dragon fruit plantations were identified using microscopy and genetic sequencing (ITS, EF-1α, and beta-tubulin). The selected fungi were isolates closely related to Talaromyces tumuli, Trichoderma asperellum, and Paecilomyces lagunculariae. All isolates were tested for pathogenicity using detached cladode assays at the laboratory, and non-phytopathogenic monomorphic cultures were further evaluated in the field under a randomized complete block design consisting of T. asperellum, Talaromyces tumuli, a combination of both, and a water control. The combination of T. asperellum and Talaromyces spp. showed a favorable trend in terms of the plants’ vegetative development. However, inoculating Talaromyces tumuli into the commercial plants exhibited a slow response during the first 20 days of the field evaluations. Still, it resulted in a significant increase in the fruit’s diameter and weight, with increases of 88.23% and 67.64%, respectively, compared to those in the control. T. asperellum presented a lower number of fruits per plant, although it showed an increase in fruit diameter and weight. In conclusion, using the native beneficial fungi T. asperellum and T. tumuli contributes positively to the dragon fruit production system. Full article

This paper critically examines the consequences of land grabs for livelihoods and agrarian change, based on a case study of rubber plantations in ethnic minorities in the uplands in Northwest Vietnam. Building upon Scoones’ agrarian political economy of livelihood framework, an integrated conceptual framework of a ‘livelihood pathway’ is developed to analyze the impact of rubber plantation land grabs on livelihoods and the agrarian political economy. Drawing on qualitative analysis and survey data from 205 households across six villages inhabited by Thai, Hmong, and Kho Mu communities, this study finds that rubber plantation land grabs have led to differentiated livelihood strategies—ranging from subsistence farming and wage labor to commercial agriculture—shaped by each group’s socioeconomic status, political connections, and access to resources. Consequently, the land grabbing undertaken by a domestic state-owned enterprise has caused the emergence of a set of distinctive livelihood pathways within a complex web of intersections across class and ethnicity in the upland area. This study concludes by arguing that an integrated conceptual framework of a ‘livelihood pathway’ offers a useful tool for analyzing the long-term socio-political consequences of land grabbing in similar contexts across developing countries and beyond. Full article

Forest plantations in the Neotropics aim to alleviate pressure on primary forests. This study synthesizes knowledge on pine species used in these plantations, emphasizing the challenges and potential of ectomycorrhizal fungi and bacteria as inoculants. An analysis of 98 articles identifies 23 pine species in Mexico and Central America and about 16 fast-growing species in South America. While pine plantations provide a habitat for generalist species, they reduce the richness of specialist species. Ectomycorrhizal fungi and bacterial diversity in plantations with introduced pines is up to 20% lower compared to native ecosystems. Suillus and Hebeloma are commonly used as mycorrhizal inoculants for Neotropical and introduced species, including Pinus ponderosa and Pinus radiata in South America. Commercial inoculants predominantly feature the fungal species Pisolithus tinctorius, alongside bacterial genera such as Bacillus, Cohnella, and Pseudomonas. This study emphasizes the importance of leveraging native microbial communities and their synergistic interactions with ECM fungi and bacteria to enhance seedling growth and quality. Such a combined approach can improve plantation survival, boost resilience to environmental stressors, and promote long-term productivity. These findings underscore the need to incorporate native fungi and bacteria into inoculant strategies, advancing sustainable forestry practices and ecosystem adaptation in the Neotropics. Full article

Lycium barbarum L. is a shrub native to China. It produces berries that are high in nutraceutical value. Its commercial appeal has led to the development of new plantations in Italy over recent decades. The majority of cultivated goji plants are derived from local nursery seedlings without the selection of varieties or clones. This study used nine simple sequence repeats (SSRs) from Lycium chinense L. to analyze the genetic structure and variability of heterogeneous, seed-derived accessions cultivated in an orchard located in central Italy (from here on referred to as field). The results were compared to accessions of known origin (LB, Lycium barbarum; LC, Lycium chinense). The study aimed to determine the genetic origin of seedlings and assess the feasibility of using microsatellite markers for individual fingerprinting. It also aimed to propagate the most adapted, productive plants while ensuring traceability and protection of potential clones throughout the production chain. The SSR markers used revealed that the field accessions were genetically distinct from both the L. barbarum and L. chinense accessions, whose seeds came from different European Botanical Gardens. The mean observed heterozygosity (H_o) across the three groups was 0.356, higher than the mean expected heterozygosity (H_e) of 0.314. The values of the inbreeding coefficient (F_IS) ranged from −0.25 (field) to 0.05 (LC), confirming the high genetic variability in our dataset. The fixation index (F_ST) was 0.234, indicating medium to high genetic differentiation. The Bayesian analysis revealed three distinct clusters, indicating that three gene pools influenced the genetic structure of the studied populations. The orchard accessions form a distinct population, most likely a L. barbarum landrace, descended from two distinct ancestral populations that differ from the two known species. Our findings preliminarily lay the groundwork for the protection of some clonal lines of goji accessions for use in future planting more suited to the Mediterranean climate. This study also serves as a foundation for a more thorough characterization of cultivated L. barbarum, allowing for traceability and sustainable management of the genetic resource. Full article

Retrophyllum rospigliosii is a valuable conifer species from the Andean tropical forests, reaching diameters up to 2.5 m and heights of 45 m. Due to its high commercial demand and distinctive shape and size, its wood is highly sought after, leading to its classification as vulnerable on the IUCN Red List. This study evaluated the physical and mechanical properties of R. rospigliosii wood and how these properties vary according to tree diameter and height in plantation-grown specimens in the Cauca department, Colombia. Standard physical and mechanical tests followed international procedures to assess density, dimensional stability, and mechanical performance. The results showed stable wood density, with a basic wood density of 0.35 g/cm³, and a green density of 0.54 g/cm³. Volumetric shrinkage was 3.52% in the radial direction and 5.05% in the tangential direction, indicating good dimensional stability. Mechanical properties included a modulus of rupture (MOR) of 58.23 MPa, a modulus of elasticity (MOE) of 4702.23 MPa in static bending, and a compression strength of 54.08 MPa. Wood properties showed minimal variation across different diameter and height classes, indicating structural uniformity within the plantation. Given these characteristics, R. rospigliosii wood is suitable for non-structural applications such as furniture, moldings, and decorative items. Further studies should explore silvicultural strategies that enhance wood quality while ensuring sustainable management and conservation of this threatened species. Full article

In order to explore the effects of planting two economic crops in Moso plantations on the composition of soil phosphorus-functional microbial community, this study collected soil samples of Persimmon and Tea-oil plantations cultivated on the original bamboo soil for 3 years for comparison. Soil physical and chemical measurements and metagenomic sequencing were used to evaluate the effects of crop cultivation on the diversity of soil phosphorus-functional microorganisms. Results show that (1) Moso forests are converted to different crops after the soil pH values decline, and other physical and chemical properties of soil and microbial biomass phosphorus (MBP) content rise. (2) Soil microbial community structure changed with crop planting. The number of phosphorus-functional bacteria in Persimmon soil was higher than Tea-oil and Moso soils, with the total number of phosphorus-functional bacteria and unique phosphorus-functional bacteria in Persimmon soil being the highest. (3) The relative abundance of phoU, phoR, ugpA, ugpB, gcd and ppaC genes was significantly increased, while the abundance of pstA, pstB and pstC genes was decreased by crop replanting. (4) The dominant phosphorus-functional microorganisms under different crop cultivation were closely related to basic soil properties. Bradyrhizobium and Camellia abundances were significantly positively correlated with soil total phosphorus (TP), while Sphingomonas was significantly negatively correlated with soil TP. Soil electrical conductivity (EC), soil total nitrogen (TN) and soil MBP were positively correlated with the ppx–gppA gene. AP, EC and TN were positively correlated with the phoB gene, while TN and MBP were negatively correlated with the phoP gene. These results suggested that land use patterns could directly change soil environmental conditions, thereby affecting phosphorus-functional microbial communities. In conclusion, the conversion of Moso plantations to commercial crops is beneficial for the optimization of the soil system, promoting the activation and release of soil phosphorus to maintain the dynamic balance of soil microbial community. Full article

Capsicum annuum L. var. glabriusculum is a semi-domesticated species of economic importance; however, its establishment in commercial plantations has been hampered by the low germination and emergence rates of its seeds. The aim of this study was to evaluate the effect of the fruit ripening stage on seed germination and seedling emergence in C. annuum var. glabriusculum. Seeds were extracted from fruits with six different ripening stages. The evaluated traits were the germination and emergence percentages, germination and emergence rates, and 17 physical traits of the seeds. According to the results, seeds extracted from red, orange, and pinto fruits presented better germination and seedling emergence percentages (85, 86, and 82% and 95, 93, and 94%, respectively). A principal component analysis showed that some differences in the physical traits of the seed were associated with the fruit ripening stages and seed development. A canonical discriminant analysis showed a high correlation between the fruit ripening stages and the physical and physiological characteristics of the seed, allowing the formation of four groups. The fruit ripening stages (pinto, orange, and red) influence the germination of the seeds and the emergence of the seedlings of C. annuum L. var. glabriusculum, so obtaining seeds from physiologically ripe fruits allows for obtaining seeds of better quality. Full article