Search Results (83)

The agronomic effectiveness of biofertilizers is influenced by strain origin, genetic identity, crop genotype, soil type, and environmental conditions. For best results, both the plant and rhizobia strain must be adapted to the common harsh soil conditions in the tropics. While plant varieties have changed over the years, complementary research on new strains effectiveness under varying soil fertility conditions has lagged in southern Africa. Seven field experiments were established in the main soybean-producing areas of Zimbabwe in the north, central, and north–east regions to evaluate agronomic benefits of new rhizobia strains against the current exotic commercial strain (MAR1491). One site was irrigated (site 3), and the other six sites were rainfed (sites 1, 2, 4, 5, 6, and 7). While trends in inoculation response varied from site to site due to site conditions, inoculation with the strains NAZ15, NAZ25, and NAK128 consistently yielded high grain yields, which were similar to the current commercial strain MAR1491 and to application of mineral fertilizer (51.75 and 100 kg N ha⁻¹). Grain yield levels were generally below 2 t ha⁻¹ for sites 2, 3, and 5 and above 2 t ha⁻¹ for sites 1, 4, and 6, while for the irrigated site 3, they ranged upwards of 3 t ha⁻¹. When irrigated, all strains except NAK9 performed similarly in terms of grain yields and aboveground N uptake. Further testing on the inclusion of the indigenous strains NAZ15, NAZ25, and NAK128 in multi-strain commercial inoculant production targeting application in regions and soils where they excel beyond the current exotic strain MAR1491 is recommended. Full article

Oases in arid regions are critical ecosystems, providing essential ecological, agricultural, and socio-economic functions. However, urbanization and climate change increasingly threaten their sustainability. This study examines land cover (LULC) and land surface temperature (LST) dynamics in four representative North African oases: Tolga (Algeria), Nefta (Tunisia), Ghadames (Libya), and Siwa (Egypt) over the period 2000–2023, using Landsat satellite imagery. A three-step analysis was employed: calculation of NDVI (Normalized Difference Vegetation Index), NDBI (Normalized Difference Built-up Index), and LST, followed by supervised land cover classification and statistical tests to examine the relationships between the studied variables. The results reveal substantial reductions in bare soil (e.g., 48.10% in Siwa) and notable urban expansion (e.g., 136.01% in Siwa and 48.46% in Ghadames). Vegetation exhibited varied trends, with a slight decline in Tolga (0.26%) and a significant increase in Siwa (+27.17%). LST trends strongly correlated with land cover changes, demonstrating increased temperatures in urbanized areas and moderated temperatures in vegetated zones. Notably, this study highlights that traditional urban designs integrated with dense palm groves significantly mitigate thermal stress, achieving lower LST compared to modern urban expansions characterized by sparse, heat-absorbing surfaces. In contrast, areas dominated by fragmented vegetation or seasonal crops exhibited reduced cooling capacity, underscoring the critical role of vegetation type, spatial arrangement, and urban morphology in regulating oasis microclimates. Preserving palm groves, which are increasingly vulnerable to heat-driven pests, diseases and the introduction of exotic species grown for profit, together with a revival of the traditional compact urban fabric that provides shade and has been empirically confirmed by other oasis studies to moderate the microclimate more effectively than recent low-density extensions, will maintain the crucial synergy between buildings and vegetation, enhance the cooling capacity of these settlements, and safeguard their tangible and intangible cultural heritage. Full article

Soybean (Glycine max) is a protein-rich legume crop that plays an important role in achieving food security. The aim of this study was to isolate soybean-nodulating rhizobia from Côte d’Ivoire soils and evaluate their potential as efficient strains in order to develop local bioinoculants. For this objective, 38 composite soil samples were collected from Côte d’Ivoire’s five major climatic zones. These soils were used as substrate to trap the nodulating rhizobia using the promiscuous soybean variety R2-231. A total of 110 bacterial strains were isolated and subsequently identified. The analysis of ITS (rDNA16S-23S), glnII and recA sequences revealed a relatively low genetic diversity of these native rhizobia. Moreover, the ITS phylogeny showed that these were scattered into two Bradyrhizobium clades dominated by the B. elkanii supergroup, with ca. 75% of all isolates. Concatenated glnII-recA sequence phylogeny confirmed that the isolates belong in the majority to ‘B. brasilense’, together with B. vignae and some putative genospecies of Bradyrhizobium that needs further elucidation. The core gene phylogeny was found to be incongruent with nodC and nifH phylogenies, probably due to lateral gene transfer influence on the symbiotic genes. The diversity and composition of the Bradyrhizobium species varied significantly among different sampling sites, and the key explanatory variables identified were carbon (C), magnesium (Mg), nitrogen (N), pH, and annual precipitation. Based on both shoot biomass and leaf relative chlorophyll content, three isolates consistently showed a higher symbiotic effectiveness than the exotic inoculant strain Bradyrhizobium IRAT-FA3, demonstrating their potential to serve as indigenous elite strains as bioinoculants. Full article

Bulgarian botanical gardens harbor more than 3600 plant species from across the world. Some of them are well-known plants widely used by humans, others are underutilized crops or little-known exotic species. The latter group constitutes a rich reservoir of plant resources whose potential to bring benefits to society is still untapped. The aim of this review is to describe the diversity of species and their potentially valuable secondary metabolites in three of the largest Bulgarian botanical gardens, with a focus on underutilized crops and medicinal plants that are typical of Bulgaria. With this, we aim to pave the way for future research on the most promising of these plants. The report includes currently available ethnobotanical data on the properties and composition of their bioactive components, known culinary or therapeutic uses, and nutritional profiles. We also outline the vast potential of these plants in providing healthy diets, as well as for performing future groundbreaking biomedical research. Finally, we present the approach that will be used to screen extracts from these plants for biological activity. Full article

Dragon fruit or pitaya (Hylocereus sp.) is an exotic tropical plant gaining popularity in the United States as it is a nutrient-rich fruit with mildly sweet flavor and a good source of fiber. Although high tunnels are being used to produce specialized crops, little is known about how pitaya growth, physiology and nutrient uptake change throughout the production period. This study aims to evaluate the impact of high tunnels and varying rates of vermicompost on three varieties of pitaya, White Pitaya (WP), Yellow Pitaya (YP), and Red Pitaya (RP), to assess the soil and plant nutrient dynamics, spectral reflectance changes and plant growth. Plants were assessed at 120 and 365 DAP (Days After Plantation). YP thrived in a high tunnel compared to an open environment in terms of survival before 120 DAP, with no diseased incidence and higher nutrient retention. The nutrient accumulation in the RP, WP, and YP shoot samples 120 DAP were ranked in the following order, K > N > Ca > Mg > P > Fe > Zn > B > Mn, while 365 DAP, they were ranked as K > Ca > N > Mg > P > S > Fe > Zn > B > Mn. The nutrient accumulation in the RP, WP, and YP, soil samples 120 and 365 DAP were ranked in the following order: N > Ca > Mg > P > K > Na > Zn. Soil nutrients showed a higher concentration of Na and K grown inside the high tunnels in all three pitaya species due to the increased concentration of soluble salts. Spectral reflectance analysis showed that RP and WP had higher reflectance in the visible and NIR region compared to YP due to their higher plant biomass and canopy cover. This study emphasizes the importance of environmental conditions, nutrition strategies, and plant physiology in the different pitaya plant species. The results suggest that high tunnels with appropriate vermicompost can enhance pitaya growth and development. Full article

This study focuses on identifying and assessing the extent of anthropogenic disturbance factors directly affecting the forests of northwestern Virunga. It posits that the army camps within the forest are a hotspot for expanding human activities in the context of armed conflict. A multiscalar approach was used to examine disturbances across multiple levels to capture their complex interaction and to avoid oversimplified interpretations. This approach included an analysis of the dynamics and spatial structure of the forest cover from 2016 to 2023, along with an inventory of the local disturbance factors. The study focused on seven study sites hosting army camps, namely Mikuha, Lahe, Pk26, and Ngite within Virunga National Park, as well as Mamundioma, PK2, and Kinziki in its periphery. The findings show that the installation of army camps did not lead to significant forest fragmentation. Except for Mamundioma, all the other sites showed an increase in forest areas, due to the aggregation of remaining forest patches during periods of insecurity. However, this trend toward passive forest restoration does not offset disturbances. It merely reflects a slowdown in the conversion of forest areas to other land uses. Nine anthropogenic factors contribute to forest disturbances, with cash crops (74.17%), food crops (72.50%), and trees cut down for energy (61.61%) being the most prominent. Other contributing factors include carbonization (31.67%), fire use (30.00%), sawn timber (26.67%), path creation (17.50%), exotic tree species introduction (10.00%), and the establishment of invasive species (11.67%). Spatial analysis provides a partial explanation for such forest disturbances. Its exhaustive description would require a mix of spatial data and field observations. Full article

South African farming households face several challenges regarding food security, poverty, micronutrient deficiencies and hidden hunger. This is due to millions of households lacking access to food and an adequate food basket. Consumption of indigenous crops has been proposed to help sustain vulnerable households since these crops have low production costs and are climate-resilient. However, research has found the consumption of these crops across South Africa to be relatively low. This study aims to examine the factors associated with the consumption of indigenous crops among farming households in the KwaZulu-Natal province of South Africa. A sample of 260 farming households was selected using simple random sampling. The results showed that farmers commonly cultivate exotic crops, such as spinach, cabbage, carrot, and butternut, more than any indigenous crops, except for a few cultivating taro and sweet potato. The binomial logit regression results revealed that an increase in the number of females and children within a household and farmers’ experience increased the likelihood of consuming indigenous crops, whilst monthly food expenses decreased the likelihood of consuming indigenous crops. There is a considerable gap between the consumption and production of indigenous crops. The findings established that although many farming households indicated that they consume indigenous crops, this was not reflected in their cultivated crops. The study also concluded that farming households may be more aware of the nutritional benefits of indigenous crops, since an increase in the number of children in a household was linked to an increase in consumption of these crops. Additionally, experience in farming is vital, as it increases the consumption of indigenous crops. The study recommends government interventions that include increasing the production of indigenous crops by including them alongside the cultivation of exotic crops. Future work should also focus on awareness programs to promote the nutritional benefits of consuming indigenous crops. This, coupled with training centered on indigenous crops, could incentivize farming households to cultivate more of these crops for easier access. Full article

Cryptostylis ovata is a terrestrial orchid endemic to southwestern Australia. The virus status of C. ovata has not been studied. Eighty-three C. ovata samples from 16 populations were collected, and sequencing was used to identify RNA viruses from them. In one population, all tested plants were co-infected with isolates of the exotic-to-Australia viruses Ornithogalum mosaic virus (OrMV) and bean yellow mosaic virus (BYMV). In another population, one plant was infected with BYMV. No viruses were detected in the remaining populations. The OrMV isolate shared 98–99% nucleotide identity with isolates identified from wild indigenous Lachenalia (Iridaceae) plants in South Africa. This suggests that the source of OrMV in C. ovata may be one or more bulbous iridaceous flowering plants of southern African origin that were introduced to Western Australia as ornamentals and that have since become invasive weeds. One BYMV isolate from C. ovata also exhibited 99% nucleotide identity with strains isolated from the exotic leguminous crop Lupinus angustifolius in Western Australia, suggesting possible spillover to indigenous species from this source. This study with C. ovata highlights the probable role of invasive weeds and exotic crops as sources of exotic virus spillovers to indigenous plants. Full article

Pitahaya or dragon fruit is an exotic fruit native to Mesoamerica and is cultivated in several regions of the world. In recent years, pitahaya has become increasingly in demand, firstly, for its good nutritional and organoleptic qualities and, secondly, for its richness in antioxidants and bioactive compounds. Spain has opted for new tropical crops, and among them, pitahaya is one of the most planted in recent years. Most of the investigations on pitahaya were conducted with red cultivars, while the research on yellow pitahaya (Selenicereus megalanthus Haw.) is very scarce. In this review, the current knowledge about types of pitahayas, the fruit growth and ripening, the quality attributes, the postharvest storage, the use of by-products, and the health attributes were covered. Full article

Wild edible trees (WETs) play an important role in the diet of many rural communities. Therefore, research on their use and management is important to support both food sovereignty and local conservation of biocultural resources. We evaluated the different uses of WETs by the community of Zacualpan, Colima, in western Mexico, through 32 semi-structured interviews registering the species richness, plant parts consumed, and non-food uses. Additional information was collected on their management, availability, and forms of preparation. We used a cultural salience index to determine the food importance of the WETs mentioned. We registered 33 edible tree species (26 wild, 3 native crops, and 4 exotic crops) that were most commonly consumed as fruits or seeds. WETs were also used for fuel, live fences, timber, handicrafts, medicine, shade, fodder, poles, utensils, construction, tanning, soap, and paper. Pithecellobium dulce had the highest food salience, followed by Spondias purpurea, Leucaena esculenta, Leucaena leucocephala, Enterolobium cyclocarpum, and Jacaratia mexicana. Salient wild trees were collected in the wild and promoted in agroforestry systems. These trees provided food during the dry season and also had the highest number of additional uses. Promoting the biocultural value of WETs and their sustainable use can favor ecosystem conservation and local food sovereignty. Full article

Sugar beet (Beta vulgaris L.) is a biennial herb belonging to the Amaranthaceae family. It contributes to approximately 30% of the world’s total sucrose production and is an economically important crop. In this study, we analyzed the genetic diversity and population structure of 132 exotic sugar beet varieties using three molecular makers: four pairs of simple sequence repeat (SSR) primers, three pairs of insertion–deletion sequence (InDel) primers, and 20 cis-element amplification polymorphism (CEAP) primers. The results indicated that the number of alleles (Na) was 298, among which the number of effective alleles (Ne) was 182.426 (accounting for approximately 61.2%). The mean value of the genetic diversity index was 0.836. The polymorphic information content (PIC) was 0.639–0.907 (mean = 0.819), indicating a high level of polymorphism. These sugar beet varieties were classified into six clusters using the UPGMA method of cluster analysis. Population structure analysis revealed that the most ideal K value was 6. This indicated that the test materials could be divided into six categories, consistent with the clustering results. The clustering results indicated that most sugar beet varieties from the same breeding company clustered together, and the genetic distance between them was small, indicating that they may share the same male and/or female parent. Some varieties from different companies clustered together, indicating a narrow genetic base and potential exchange of germplasm resources between breeding companies. This study revealed the genetic differences among exotic sugar beet varieties and characteristics of the population structure. It provided a scientific basis for the identification of sugar beet varieties and markers-assisted breeding in China in the future. Full article

The increasing occurrence of dry and hot summers generates chronic water deficits that negatively affect tree radial growth. This phenomenon has been widely studied in natural stands of native species but not in commercial plantations of exotic tree species. In central Chile, where the species is increasingly planted, the dynamics of stone pine (Pinus pinea L.) growth under drought have been little explored. We studied the impact of drought on four stone pine plantations growing in central Chile. We sampled and cross-dated a total of 112 trees from four sites, measured their tree-ring width (RWL) series, and obtained detrended series of ring width indices (RWIs). Then, we calculated three resilience indices during dry years (Rt, resistance; Rc, recovery; and Rs, resilience), and the correlations between the RWI series and seasonal climate variables. We found the lowest growth rate (1.94 mm) in the driest site (Peñuelas). Wet conditions in the previous winter and current spring favored growth. In the wettest site (Pastene), the growth rates were high (4.87 mm) and growth also increased in response to spring thermal amplitude. Overall, fast-growing trees were less resilient than slow-growing trees. Drought reduced stone pine stem growth and affected tree resilience to hydric deficit. At the stand level, growth rates and resistance were driven by winter and spring precipitation. Fast-growing trees were more resistant but showed less capacity to recover after a drought. In general, stone pine showed a high post-drought resilience due to a high recovery after drought events. The fact that we found high resilience in non-native habitats, opens new perspectives for stone pine cropping, revealing that it is possible to explore new areas to establish the species. We conclude that stone pine shows a good acclimation in non-native, seasonally dry environments. Full article

Pinus pinea (stone pine), a Mediterranean species, is valued for its highly nutritious pine nuts and its ability to adapt to different environmental conditions. The species has been increasingly planted in Chile, where its main ecological requirements are met across a vast area. However, new plantations are established without considering social dimensions. Policymakers can regulate private decisions on tree planting through the appropriate design of economic incentives to foster social well-being. The objective of this work was to describe spatial patterns of potential areas for the cultivation of the exotic nut-bearing conifer P. pinea in central Chile and the possible correlation of those patterns with human development indices. Spatial data layers of the municipality development index (MDI), elevation, edaphoclimatic variables, and stone pine nut’s productive potential were overlapped at the municipality scale along 1225 km in central Chile. A spatial principal component analysis (sPCA) was used to integrate multiple dimensions, summarizing covariation structures, and identifying spatial patterns in the study area. Key results showed that spatial patterns of the potential productive index (PPI) were strongly regulated by the spatial pattern of climate and soil variables, whereas the spatial pattern of MDI showed a cryptic pattern and that the three dimensions of MDI—welfare, economy, and education—showed a different spatial movement, especially education and welfare. The results allow us to recommend that public policies boost municipality development through the promotion of P. pinea plantations and should target areas with a high productive potential and low MDI to generate socio-economic improvements. These findings are useful for the strategic spatial planning of the species cropping in Chile. Full article

Conservation systems involving trees enhance the sustainability of tropical soils. However, little is known on the effect of integrated systems with native and exotic trees on soil chemical quality in the eastern Amazon. We aimed to measure changes in soil chemical quality in integrated production systems in Pindaré-Mirim, Maranhão, Brazil. This study was carried out in 2017 and 2018, evaluating (i) perennial pasture; (ii) crop–livestock–forest integration-I (CLFI-I)—eucalyptus rows interspersed with maize + Urochloa brizantha intercropping; (iii) CLFI-II—babassu palm trees (Attalea speciosa Mart.) with maize + Megathyrsus maximus intercropping; and (iv) maize + M. maximus intercropping. Soil chemical attributes at depths of 0.00–0.10 m, 0.10–0.20 m, 0.20–0.30 m, and 0.30–0.50 m, forage productivity, and soil cover were evaluated. CLFI-II promoted the highest soil organic matter concentration in topsoil and highest pH, lowest Al³⁺ levels, and potential acidity (H+Al) at all soil depths. Soil under pasture showed the highest N, K⁺, Ca²⁺ concentrations, sum of bases, and cation exchange capacity. Changes in CLFI-II are associated with the babassu palm’s ability to modulate the surrounding environment, giving the species a competitive advantage in anthropic environments. The time of adoption is crucial for improving soil fertility in the Brazilian eastern Amazon. Sustainable production systems in the region must comply with long-term management plans. Full article

Pomacea canaliculata, as an invasive exotic species in Asia, can adversely affect crop yields, eco-environment, and human health. Application of molluscicides containing metaldehyde is one effective method for controlling P. canaliculata. In order to investigate the effects of metaldehyde on adult snails, we conducted acute toxicological experiments to investigate the changes in enzyme activities and histopathology after 24 h and 48 h of metaldehyde action. The results showed that the median lethal concentrations (LC) of metaldehyde on P. canaliculata were 3.792, 2.195, 1.833, and 1.706 mg/L at exposure times of 24, 48, 72, and 96 h, respectively. Treatment and time significantly affected acetylcholinesterase (AChE), glutathione S-transferase (GST), and total antioxidant capacity (TAC) activity, with sex significantly affecting AChE, GST, and TAC activity and time significantly affecting carboxylesterase (CarE). In addition, the interaction of treatment and time significantly affected the activity of GST, CarE and TAC. In addition, histopathological changes occurred in the digestive glands, gills and gastropods of apple snail exposed to metaldehyde. Histological examination of the digestive glands included atrophy of the digestive cells, widening of the hemolymph gap, and an increase in basophils. In treated snails, the hemolymph gap in the gills was widely dilated, the columnar cells were disorganized or even necrotic, and the columnar muscle cells in the ventral foot were loosely arranged and the muscle fibers reduced. The findings of this study can provide some references for controlling the toxicity mechanism of invasive species. Full article