Diversity Of Legumes Research Articles

Riqueza y distribución de leguminosas en un gradiente ambiental dentro del Área Natural Protegida Altas Cumbres, Tamaulipas, México

Background: Altas Cumbres is a protected natural area located in the center of the state of Tamaulipas, which has not been sufficiently studied. Although legumes are a family well represented in the area, until now, no studies had been carried out to reveal their richness and distribution. Questions: How many and which legume species are found in the study area and how are they distributed along an environmental gradient? Species study: Fabaceae family. Study site and dates: Altas Cumbres, Tamaulipas, Mexico, during 2022 and 2023. Methods: Botanical material was collected and identified using specialized bibliography; Herbarium specimens and online databases were reviewed. An analysis of similarity was carried out with the sites studied, using the Jaccard index to obtain β diversity and observe its distribution. Results: A total of 132 species were obtained, belonging to 57 genera and three subfamilies. The greatest diversity of legumes belonged to the subfamily Papilionoideae (86 species / 37 genera), followed by Caesalpinoideae (41/18) and finally Cercidoideae (5/2). Herbaceous plants were dominant with respect to woody plants. Most species were recorded in an elevation range between 300 and 499 m asl, in submontane scrub and pine-oak forest communities. Conclusions: Altas Cumbres is an important reservoir for legumes from Tamaulipas and Sierra Madre Oriental considering its high richness and endemism (33 species restricted to Mexico).

The Fabaceae in Northeastern Mexico (Subfamilies Caesalpinioideae (Excluding Tribe Mimoseae), Cercidoideae, and Detarioideae).

As part of the Fabaceae project of northeastern Mexico and based on field work, collection of botanical samples over the past 37 years, and reviewing botanical materials in national and international herbaria, the diversity of legumes of the subfamilies Caesalpinioideae (excluding tribe Mimoseae), Cercidoideae, and Detarioideae in northeastern Mexico has been recorded. New nomenclatural changes in tribes and genera of the subfamily Caesalpinioideae found in the new scientific bibliography are included. The subfamily Caesalpinioideae (excluding the tribe Mimoseae) includes five tribes: tribe Caesalpinieae, with eight genera (Caesalpinia, Coulteria, Denisophytum, Erythrostemon, Guilandina, Hoffmannseggia, Haematoxylum, and Pomaria) and 21 species; tribe Cassieae with three genera (Cassia, Chamaecrita, and Senna) and 28 species; tribe Ceratonieae with one genus (Ceratonia) and 1 species; tribe Gleditsieae with one genus (Gleditsia) and 1 species. The subfamily Cercidoideae includes two genera (Bauhinia and Cercis) and eight species, and the subfamily Detarioideae includes only one genus and one species (Tamarindus indicus). The total flora of these three subfamilies comprises 18 genera and 63 species, including 56 native species and 7 exotic ones: Bauhinia variegata, Cassia fistula, Ceratonia siliqua, Delonix regia, Erythrostemon gilliesii, Senna alata, and Tamarindus indicus. Endemism includes a total of 22 species and nine infraspecific categories.

Management and breeding for rust resistance in legumes

AbstractRust diseases are a major concern in legume production worldwide causing heavy losses especially in developing countries that depend on grain legumes as staple food. Fungal species from Uromyces, Phakopsora and Puccinia genera are the main causal agents of the various legume rust diseases. They induce up to 100% yield losses on susceptible cultivars and are emerging as a substantial threat to global food security. Developing durable resistance to rust has thus become a critical breeding objective alongside efforts to improve cultural and disease management practices. This review specifically focuses on the recent advances in understanding and enhancing genetic rust resistance across diverse legume crops. Key topics covered include: (i) the diversity and host range of the rust species affecting legumes; (ii) the disease management strategies from cultural practices to chemical control; (iii) the available screening methods for identifying new sources of resistance; (iv) the genetic basis of resistance, encompassing both major resistance genes and quantitative trait loci; (v) insights into gene regulation and effector molecules leading to legume-rust interactions; and (vi) emerging genomic-assisted breeding techniques that can accelerate the development of durable rust resistance in legumes. Overall, this review highlights the progress made to date and the remaining challenges in sustainably managing rust diseases across diverse legume crops through integrated approaches spanning pathogen biology, advanced phenotyping, genetic resistance, and molecular breeding.

Advancements in Genetic Enhancement: CRISPR/Cas-Mediated Genome Editing in Leguminous Crops

Legumes play a crucial role in human nutrition and sustainable agriculture due to their high protein content and health-promoting phytochemicals. To accelerate genetic gain in yield, stress resilience, and nutritional quality, extensive efforts are underway. Recent advancements in genomic resources have paved the way for the application of cutting-edge breeding technologies like genomic selection and genome editing in legume crops. This review focuses on the latest advancements in CRISPR/Cas9-based gene editing technology, specifically tailored for improving traits in legume crops. While successful gene-editing methods have been established for crops like soybean, cowpea, and chickpea, challenges remain, particularly in overcoming the recalcitrance of certain legumes to gene transfer and regeneration in vitro. Strategies to enhance transformation and regeneration rates through modifications in culture methods and DNA delivery are discussed. Despite the potential benefits of gene editing in legume breeding, regulatory barriers pose significant challenges. A comparison of regulatory environments in different regions sheds light on the importance of favourable regulations and public acceptance for realizing CRISPR's potential in enhancing global food security. Additionally, leguminous crops are vital for their nutritional properties, nitrogen-fixing abilities, and contribution to sustainable agriculture. Traditional breeding methods focused on increasing yield, while recent advancements in genome editing techniques, notably CRISPR-Cas technology, have revolutionized the improvement of agronomic traits in legumes. This chapter provides insights into the application of genome editing tools for enhancing traits such as stress tolerance, yield, and seed content in grain legumes. Furthermore, it discusses the challenges and prospects associated with enhancing grain legumes using molecular breeding techniques. Genome editing has been successfully employed in diverse legumes, including model species like Medicago and widely cultivated crops such as soybean and chickpea, offering exciting opportunities for enhancing agronomic characteristics.

Diversity, conservation and utilization of grain legumes: A potential source for food and nutritional security in Nepal

Grain legumes are precious crops of Nepal in terms of the dietary protein supplement ample concentration of micronutrients, and role in crop intensification and ameliorating soil fertility. About 11% of the cultivated area is occupied by grain legumes that include lentil, chickpea, grasspea, fieldpea, fababean, pigeonpea, soybean, blackgram, horsegram, ricebean, cowpea, and mungbean. About 100 genera and 379 species of legumes are distributed in diverse agroecological zones ranging from terai to the alpine region of Nepal, with growth habits ranging from annual to perennial shrubs. Out of the 379 species of legumes which include grain, vegetable, and forage legumes, 262 are native, and 20 species belonging to the sub-group Papilionacae are used as food legumes. Highest food legume species diversity has been recorded in Macrotyloma (34 spp.), followed by Crotalaria (18 spp.), Vigna (15 spp.), Lathyrus (7 spp.), Vicia (6 spp.), Cajanus (5 spp.), Trigonella (5 spp.) and Phaseolus (4 spp.). Other genus having 1-3 species includes Cicer (3 spp.), Mukuna (3 spp.), Glycine (2 spp.), Canavila (2 spp.), Pisum (2 spp.), Lablab (2 spp.), Pachyrrhizus (1 sp.), Psophocarpus (1 sp.), Lens (1 sp.) and Cyamopsis (1 sp.). Research on grain legumes was initiated in 1976 and a systematic collection of grain legume landraces was done in 1987 by the Grain Legumes Research Program (GLRP). Past collection missions organized in collaboration with the International Development Research Centre (IDRC), the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), the International Center for Agricultural Research in the Dry Areas (ICARDA), and other institutes have resulted in the collection of 1107 landraces and provided an opportunity for their inclusion in the variety improvement program. National Agricultural Genetic Resources Center (NAGRC) has conserved 2936 landraces of different legumes, 951 landraces have been kept in gene banks of ICARDA center, while GLRP Khajura has active collections of 218 landraces and 627 exotic germplasm of various legume crops. Varietal improvement programs resulted in the development of 51 varieties, while 6 varietes were registered and two varieties were de-notified in food legumes (lentil, chickpea, soybean, cowpea, black gram, mungbean, pigeon pea, rice bean, faba bean, grass pea, and kidney bean).

Occurrence and diversity of stem nodulation in Aeschynomene and Sesbania legumes from wetlands of Madagascar

Legumes have the ability to establish a nitrogen-fixing symbiosis with soil rhizobia that they house in specific organs, the nodules. In most rhizobium-legume interactions, nodulation occurs on the root. However, certain tropical legumes growing in wetlands possess a unique trait: the capacity to form rhizobia-harbouring nodules on the stem. Despite the originality of the stem nodulation process, its occurrence and diversity in waterlogging-tolerant legumes remains underexplored, impeding a comprehensive analysis of its genetics and biology. Here, we aimed at filling this gap by surveying stem nodulation in legume species-rich wetlands of Madagascar. Stem nodulation was readily observed in eight hydrophytic species of the legume genera, Aeschynomene and Sesbania, for which significant variations in stem nodule density and morphology was documented. Among these species, A. evenia, which is used as genetic model to study the rhizobial symbiosis, was found to be frequently stem-nodulated. Two other Aeschynomene species, A. cristata and A. uniflora, were evidenced to display a profuse stem-nodulation as occurs in S. rostrata. These findings extend our knowledge on legumes species that are endowed with stem nodulation and further indicate that A. evenia, A. cristata, A. uniflora and S. rostrata are of special interest for the study of stem nodulation. As such, these legume species represent opportunities to investigate different modalities of the nitrogen-fixing symbiosis and this knowledge could provide cues for the engineering of nitrogen-fixation in non-legume crops.

Associations between Cardiometabolic Risk Factors and Increased Consumption of Diverse Legumes: A South African Food and Nutrition Security Programme Case Study.

The programme aimed to improve selected cardiometabolic risk (CMR) variables using a nutritional intervention among farmers who reported hypertensive disorders as hindrances during agricultural activities. The intervention had two case controls (n = 103) [experimental group-EG (n = 53) and control group-CG (n = 50)] which were tracked and whose blood pressure measurements, dietary intake, blood indices for cholesterol concentration and glucose levels from pre- and post-intervention surveys after the baseline survey (n = 112) were analysed. The interval for data collection was 12 weeks (±120 days) after five legume varieties were consumed between 3 and 5 times a day, and servings were not <125 g per at least three times per week. Sixty-five per cent of farmers were above 60 years old, with mean age ranges of 63.3 (SD ± 6.3) years for women and 67.2 (SD ± 6.7) for men. The post-intervention survey revealed that EG blood results indicated nutrient improvement with p <= 0.05 for blood glucose (p = 0.003) and cholesterol (p = 0.001) as opposed to the CG. A trend analysis revealed that cholesterol (p = 0.033) and systolic blood pressure (SBP); (p = 0.013) were statistically significant when comparing genders for all study phases. Interventions focusing on legumes can improve hypertension and cardiovascular disease and fast-track the achievement of SGDs 3 and 12 through community-based programmes.

Farmers’ Awareness of and Attitude towards Diversified Legumes Production in Singida Region, Tanzania

For an extended period, legumes have served as nutritional sources in the diets of both humans and animals. Efforts have been made to increase the yield of the legume crops in Tanzania, but there is still low awareness of and unfavourable attitudes towards legume crop diversification among farmers. The study, on which this paper is based, aimed at investigating farmers’ awareness of and attitude towards diversified legumes, specifically to analyze socio-demographic characteristics of the respondents, assess awareness of and attitude towards diversified legumes production, and determine effects of awareness of and attitude towards diversified legumes production on management practices of diversified legumes production. A cross-sectional survey was employed whereby primary data were collected from 204 legume farmers using a semi-structured questionnaire. Content analysis was conducted using Nvivo software to analyze qualitative data. For quantitative data, Likert scale analysis was employed as a method for descriptive statistics, and Principal Component Analysis was used as a method for inferential analysis. These analyses were performed using Smart PLS software. The findings of the study revealed that several factors significantly influenced smallholder farmers' awareness and perception of diversified legumes. These factors included ease of cultivation, fair distribution of seeds, food availability, increase in income level, high legume harvest, and higher profitability of legumes (p &lt; 0.05). Furthermore, the statement "enough of information" did not show statistical significance (p &gt; 0.05). However, it exhibited a positive association. Conclusively, criteria like "easy cultivation" and "fair seed distribution" had a big impact on how smallholder farmers perceived and knew about diverse legumes. However, "enough information" did not appear to have a major significance. In addition, it was found that major influences on farmers' attitudes and understanding of diversified legumes included the availability of food, rising income levels, high yields of legumes, and perceived profitability. The paper recommends for the improvement of farmers' awareness and perception of diversified legumes, fair seed distribution methods must be established that provide equal access to high-quality seeds with the help of government organizations, non-profit organizations, and seed businesses.

Assessment of Mycorrhizal Fungal Diversity in Legumes (Medicago sativa, Medicago truncatula and Trifolium rubens) from Algeria and Their Influence on Soil Physicochemical and Microbiological Properties

Background: Medicago sativa, Medicago truncatula and Trifolium rubens are legumes widely distributed in Algeria. These species hold ecological and agricultural significance and serve as a natural resource for combating desertification and as livestock fodder. Methods: Comparative investigations of arbuscular mycorrhizal fungi (AMF) colonization in the roots of these leguminous species were conducted. The physicochemical and microbiological attributes of AMF’s infectious potential were explored for all three species. The presence or absence of endomycorrhizal structures was assessed in these species. Result: The mycorrhizal infectious potential of the flora was significantly enhanced in the case of Medicago truncatula when compared to Trifolium rubens. Mycorrhization occurred at a frequency exceeding 80% in all three species. The impact of legume mycorrhizal fungi colonization on soil physicochemical properties was examined, revealing alterations in soil biological fertility, particularly in terms of phosphate and nitrogen content. Medicago truncatula exhibited a more pronounced positive influence on soil physical, chemical and microbiological characteristics when compared to Medicago sativa and Trifolium rubens. Consequently, these herbaceous species can be employed as nurse plants (facilitators) or as bio-fertilizers.

Effect of drought stress on symbiotic nitrogen fixation, soil nitrogen availability and soil microbial diversity in forage legumes

Effect of drought stress on symbiotic nitrogen fixation, soil nitrogen availability and soil microbial diversity in forage legumes

Adding a diversity of legumes to a crop decision-support system: Maintaining satisfactory accuracy while keeping the model simple

In a context of economic and environmental concerns in agriculture, legumes appear to be suitable alternative crops to diversify current cropping systems and reduce their dependence on synthetic nitrogen (N) fertiliser and protein from imported soya bean. However, legume-based cropping systems may increase N losses through nitrate leaching if the N available from legumes does not coincide with subsequent crop requirements. To help agricultural advisers manage N in these systems, we adapted the decision-support system Syst’N®, designed to assess N losses in cropping systems, to simulate three annual and one perennial legume crops: pea, faba bean, soya bean and lucerne. To this end, we adapted and simplified existing submodels of legume functioning to include them in Syst’N, to keep the latter simple. We adapted the submodels “BNF” (i.e. biological N fixation) from the STICS model and “dormancy” from the CropSyst model. We also added the ability to enter the flowering date to improve predictions (improvement in N fixation’s rRMSE from 57% to 41% and EF from 0.57 to 0.77). The equations and associated parameter set developed for the four legume crops yielded satisfying predictions of crop biomass (rMBE = 9%, EF = 0.82, rRMSE = 39%) and N content (rMBE = 5%, EF = 0.76, rRMSE = 37%). These performances support the philosophy of Syst’N® that requires minimising the number of additional parameters for users when representing new crops or processes.

Local Legumes from Dry Land of East Nusa Tenggara: Diversity, Nutritional Composition, and Their Use in Society – A Literature Study

East Nusa Tenggara (ENT) is a province in Indonesia with diverse flora, including the diversity of local legumes. It has been extensively explored and reported in various scientific publications, especially the types of legumes, their nutritional composition, and their uses in local communities. However, few literature studies still comprehensively review the types of legumes, their nutritional composition, and their utilization in the local community of ENT. So, this literature review aims to briefly review the diversity, chemical composition, and use of local legumes from the dry lands of ENT. Various studies reported that Glycine max, Arachis hypogaea, Vigna radiata (L.) R. Wilczek, Cajanus cajan, Vigna unguiculata, Phaseolus lunatus, Vigna umbellata, Lablab purpureus (L.) Sweet, Mucuna pruriens (L.) DC, Phaseolus vulgaris L, Psopocarpus tetragonolobus (L.) DC, and Pueraria montana var. lobata (Willd.) Sanjappa &amp; Pradeep nuts are commonly found in the ENT region, either cultivated by the local community or grown wild. Generally, local legumes in ENT have a relatively complete nutritional composition, which varies depending on the type of bean. The ENT's local people use local beans as a mixture of rice/corn and function as sources of protein. Future research is needed to explore the functional characteristics of each ENT local bean. In addition, it is necessary to develop formulations and other food products to utilize ENT's local legumes to diversify legume-based local food.

Elucidating the effects of organic vs. conventional cropping practice and rhizobia inoculation on rhizosphere microbial diversity and yield of peanut

Legumes such as peanut (Arachis hypogea) can fulfill most of their nitrogen requirement by symbiotic association with nitrogen-fixing bacteria, rhizobia. Nutrient availability is largely determined by microbial diversity and activity in the rhizosphere that influences plant health, nutrition, and crop yield, as well as soil quality and soil fertility. However, our understanding of the complex effects of microbial diversity and rhizobia inoculation on crop yields of different peanut cultivars under organic versus conventional farming systems is extremely limited. In this research, we studied the impacts of conventional vs. organic cultivation practices and inoculation with commercial vs. single strain inoculum on peanut yield and soil microbial diversity of five peanut cultivars. The experiment was set up in the field following a split-split-plot design. Our results from the 16 S microbiome sequencing showed considerable variations of microbial composition between the cultivation types and inoculum, indicating a preferential association of microbes to peanut roots with various inoculum and cropping system. Alpha diversity indices (chao1, Shannon diversity, and Simpson index) of soil microbiome were generally higher in plots with organic than conventional inorganic practices. The cultivation type and inoculum explained significant differences among bacterial communities. Taxonomic classification revealed two phyla, TM6 and Firmicutes were significantly represented in inorganic as compared to organic soil, where significant phyla were Armatimonadetes, Gemmatimonadetes, Nitrospirae, Proteobacteria, Verrucomicrobia, and WS3. Yields in the organic cultivation system decreased by 10–93% of the yields in the inorganic cultivation system. Cultivar G06 and T511 consistently showed relative high yields in both organic and inorganic trials. Our results show significant two-way interactions between cultivation type and genotype for most of the trait data collected. Therefore, it is critical for farmers to choose varieties based on their cultivation practices. Our results showed that bacterial structure was more uniform in organic fields and microbial diversity in legumes was reduced in inorganic fields. This research provided guides for farmers and scientists to improve peanut yield while promoting microbial diversity and increasing sustainability.

Assessment of Genetic Variability and Evolutionary Relationships of Rhizoctonia solani Inherent in Legume Crops.

Rhizoctonia solani is one of the most common soil-borne fungal pathogens of legume crops worldwide. We collected rDNA-ITS sequences from NCBI GenBank, and the aim of this study was to examine the genetic diversity and phylogenetic relationships of various R. solani anastomosis groups (AGs) that are commonly associated with grain legumes (such as soybean, common bean, pea, peanut, cowpea, and chickpea) and forage legumes (including alfalfa and clover). Soybean is recognized as a host for multiple AGs, with AG-1 and AG-2 being extensively investigated. This is evidenced by the higher representation of sequences associated with these AGs in the NCBI GenBank. Other AGs documented in soybean include AG-4, AG-7, AG-11, AG-5, AG-6, and AG-9. Moreover, AG-4 has been extensively studied concerning its occurrence in chickpea, pea, peanut, and alfalfa. Research on the common bean has been primarily focused on AG-2, AG-4, and AG-1. Similarly, AG-1 has been the subject of extensive investigation in clover and cowpea. Collectively, AG-1, AG-2, and AG-4 have consistently been identified and studied across these diverse legume crops. The phylogenetic analysis of R. solani isolates across different legumes indicates that the distinct clades or subclades formed by the isolates correspond to their specific anastomosis groups (AGs) and subgroups, rather than being determined by their host legume crop. Additionally, there is a high degree of sequence similarity among isolates within the same clade or subclade. Principal coordinate analysis (PCoA) further supports this finding, as isolates belonging to the same AGs and/or subgroups cluster together, irrespective of their host legume. Therefore, the observed clustering of R. solani AGs and subgroups without a direct association with the host legume crop provides additional support for the concept of AGs in understanding the genetic relationships and evolution of R. solani.

Arbuscular Mycorrhizal Fungi as an Important Factor Enabling the Adaptation of Anthyllis vulneraria L. to Zn-Pb-Polluted Tailings.

The old Zn-Pb-contaminated (calamine) tailings in southern Poland are spontaneously colonized by metal-tolerant Anthyllis vulneraria L. (Fabaceae), which can form simultaneously symbiotic association with nitrogen-fixing rhizobia and phosphorus-acquiring arbuscular mycorrhizal fungi (AMF). So far, fungal colonization and the AMF diversity of calamine-inhabiting legumes have been poorly studied. Thus, we determined AMF spore density in the substratum and the mycorrhizal status of nodulated A. vulneraria plants occurring on calamine tailings (M) and on a reference non-metallicolous (NM) site. The results indicate the presence of the Arum-type of arbuscular mycorrhiza in the roots of both Anthyllis ecotypes. Despite the presence of AM fungi in M plant roots, the dark septate endophyte (DSE) fungi (hyphae and microsclerotia) were occasionally also detected. Metal ions were accumulated mainly in the nodules and intraradical fungal structures rather than thick plant cell walls. Mycorrhization parameters (frequency of mycorrhization and intensity of root cortex colonization) for M plants were markedly higher and differed in a statistically significant manner from the parameters for NM plants. Heavy metal excess had no negative effect on the number of AMF spores, the amounts of glomalin-related soil proteins and AMF species composition. Molecular identification of AMF using PCR-DGGE analysis based on the 18S rDNA ribosomal gene by nested-PCR with primers AM1/NS31 and NS31-GC/Glo1 revealed similar genera/species of AMF in the roots of both Anthyllis ecotypes: Rhizophagus sp., R. fasciculatus, and R. iranicus. The results of this work indicate the presence of unique fungal symbionts, which may enhance A. vulneraria tolerance to heavy metal stress and plant adaptation to extreme conditions on calamine tailings.

Effects of Photoperiod and Drought on Flowering and Growth Development of Protein-Rich Legumes under Atlantic Environments

Legumes have an important role in European agriculture. They assimilate N2 to sustainably support maximum crop growth, in turn providing high-protein food for human consumption and livestock feed. However, the extent of the area for legume cultivation in Europe has declined due to the lower economic competitiveness of legumes in relation to other crops, particularly of cereals and oilseed. To increase yields, there is a need to increase the genetic diversity of legumes in terms of adaptation to environmental stresses. We attempted to address this by conducting field and controlled experiments under drought vs. nondrought and different photoperiod conditions. The current study identified the physiological and agronomic traits correlated with productivity and quality performance in five economically important grain legume species (Pisum sativum, Phaseolus vulgaris, Cicer arietinum, Lupinus spp., and Vicia faba). In all species, the days to flowering and seed yield were affected by temperature and photoperiod. For cool-season legume species, long-day photoperiods were favorable and days to flowering was negatively correlated with the average air temperature. For the warm-season legumes, short-day photoperiods and warm temperatures were favorable. Under drought stress, the C/N balance, leaf nutrient (Ca, Fe, and K) concentrations, and yield were significantly reduced, contrary to Zn accumulation, and this information may contribute to improving our understanding and ability to develop sustainable growth. Based on our results, we conclude that the drought-tolerant and photoperiod-insensitive legume genotypes identified in this study constitute valuable starting materials for future programs aimed at improvement of legume productivity at a global/regional scale, which helps to strengthen the competitiveness and economic growth of legumes for European farmers.

Discovering the genetic modules controlling root nodule symbiosis under abiotic stresses: salinity as a case study.

Legumes form a symbiotic association with rhizobia and fix atmospheric nitrogen in specialized root organs known as nodules. It is well known that salt stress inhibits root nodule symbiosis by decreasing rhizobial growth, rhizobial infection, nodule number, and nitrogenase activity in diverse legumes. Despite this knowledge, the genetic and molecular mechanisms governing salt stress's inhibition of nodulation and nitrogen fixation are still elusive. In this Viewpoint, we summarize the most recent knowledge of the genetic mechanisms that shape this symbiosis according to the salt levels in the soil. We emphasize the relevance of modulating the activity of the transcription factor Nodule Inception to properly shape the symbiosis with rhizobia accordingly. We also highlight the knowledge gaps that are critical for gaining a deeper understanding of the molecular mechanisms underlying the adaptation of the root nodule symbiosis to salt-stress conditions. We consider that filling these gaps can help to improve legume nodulation and harness its ecological benefits even under salt-stress conditions.

Six novel Micromonospora species associated with the phyllosphere and roots of leguminous plants: Micromonospora alfalfae sp. nov., Micromonospora cabrerizensis sp. nov., Micromonospora foliorum sp. nov., Micromonospora hortensis sp. nov., Micromonospora salmantinae sp. nov., and Micromonospora trifolii sp. nov.

Six actinobacterial strains isolated from diverse legume tissues collected in various locations in Spain were characterized to determine their taxonomic status. Using 16S rRNA gene sequencing, the strains were primarily identified as members of the genus Micromonospora with more than 99 % similarity. Digital DNA-DNA hybridization values and average nucleotide identities between the six strains and the nearest type strains confirmed that each strain represented a novel species. Genome sequences were analysed to infer their metabolic profiles, their potential to produce secondary metabolites and plant growth promoting features. Chemotaxonomic and physiological studies were carried out to complete the phenotypic characterization and to distinguish the new Micromonospora species. The genomic and phenotypic characterization of the Micromonospora strains strongly support their classification as representatives of new species with the following names: Micromonospora alfalfae sp. nov., Micromonospora cabrerizensis sp. nov., Micromonospora foliorum sp. nov., Micromonospora hortensis sp. nov., Micromonospora salmantinae sp. nov. and Micromonospora trifolii sp. nov., with the type strains MED01T, LAH09T, PSH25T, NIE111T, PSH03T and NIE79T, respectively.

Diversity of Legumes in the Cashew Agroforestry System in East Timor (Southeast Asia).

Cashew is an important export-oriented crop in several tropical countries, often under monocropping systems. Intercropping with legume species is promoted as a sustainable practice, enhancing agricultural productivity and providing nutritional food sources to rural communities. This study aimed to characterize the diversity of Leguminosae (or Fabaceae) in the cashew agroforestry systems of East Timor (Southeast Asia). Fourteen cashew orchards were sampled across the country, and information about leguminous species uses was collected from local populations. About 50 species are commonly part of the country's cashew agroforestry system, many of them simultaneously used as food, fodder, and in traditional medicine. Six bean species-Cajanus cajan (L.) Huth, Phaseolus lunatus L., Phaseolus vulgaris L., Vigna angularis (Willd.) Ohwi and H.Ohashi, Vigna radiata (L.) R.Wilczek and Vigna unguiculata (L.) Walp.-are largely used as food. The mineral contents of these beans revealed relevant differences between species and, in some cases, between types (seed colour) within species. Periods of hunger and low food variety are frequent in East Timor, reflecting a very poor nutritional state of the population. Knowing and using legumes for local nutrition, as well as for healthcare and well-being, adds great value to these species as components of East Timor cashew agroforestry systems.

The potential of regenerative agriculture to improve soil health on Gotland, Sweden

AbstractBackgroundRegenerative agriculture has gained attention in mainstream media, academic literature, and international politics in recent years. While many practices and outcomes relate to RA, there is no uniform definition of the term, and only a few comprehensive scientific studies exist of “real‐life” farms and the complexity of what is considered regenerative management and its impact on soil health.AimsThis study aimed to relate the impact of single and various combinations of regenerative management practices to soil health indicators on Gotland, Sweden.MethodsSoil health of 17 farm fields and six gardens was assessed on 11 farms that had applied regenerative agricultural practices for zero to 30 years. We measured a variety of physical (bulk density, infiltration rate, wet aggregate stability, root depth and abundance, penetration resistance), chemical (pH, electric conductivity, C:N ratio, total organic carbon) and biological (earthworm abundance, active carbon, microbial biomass carbon) soil indicators. These parameters were related to regenerative practices (reduced tillage, application of organic matter, livestock integration, crop diversity, and share of legumes and perennials) through a combination of hierarchical clustering, Analysis of Variance and Tukey's tests, principal component analysis, and multiple linear regressions.ResultsAt our study sites, the application of organic matter had a positive impact on bulk density, carbon‐related parameters, wet aggregate stability, and infiltration rate, while reduced tillage and increased share of perennials combined had a positive impact on vegetation density, root abundance and depth, and wet aggregate stability. The field plots were divided into four clusters according to their management, and we found significantly higher values of total organic carbon (*), C:N (*), infiltration rate (**), and earthworm abundance (*) for crop‐high‐org‐input, the management cluster with highest values of organic matter application and no tillage. We found significantly higher values of vegetation density (***) and root abundance (**) for perm‐cover‐livestock, the cluster with no tillage, integration of livestocks, and permanent cover (*** p &lt; 0.001, ** p &lt; 0.01, *p &lt; 0.05, °p &lt; 0.1).ConclusionsWe support existing knowledge on positive impacts of regenerative practices, namely, the addition of organic amendment that improved carbon‐related parameters, as well as the positive effects on soil structure of reduced tillage in combination with an increased share of perennials. We argue for an outcome‐based, and principle‐led concept of regenerative agriculture as a context‐dependent agricultural approach.