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Pherosphaera fitzgeraldii , the Dwarf Mountain Pine, is a critically endangered conifer restricted to cliff ledges within waterfall spray zones in the Greater Blue Mountains Area of New South Wales, Australia. This species is under threat from pollution, invasive weeds, and limited recruitment, which are contributing to its declining population. Using a comprehensive conservation genomic approach, we assessed the population health of P. fitzgeraldii and developed strategic recommendations for its management. Genomic analysis of P. fitzgeraldii revealed the presence of two distinct genetic groups despite the limited distribution of the species. This genetic structure aligns with prevailing wind currents, indicating potential restrictions to pollen or seed exchange between subpopulations. Furthermore, limited gene flow was observed even among nearby subpopulations, emphasizing the risk of increased genetic differentiation due to ongoing isolation. Clonality is widespread in some subpopulations, and all subpopulations displayed signs of inbreeding and genetic depletion despite subdioecy, indicative of historical constraints on gene flow and small population sizes. We offer genomic-based recommendations for prioritizing conservation sites, enhancing genetic diversity in ex situ collections, and guiding future management. Further studies to uncover the sex determination mechanism of P. fitzgeraldii could help maintain balanced sex ratios in ex situ collections and support future genetic rescue efforts. This study underscores the value of genomics in informing protection and recovery of unique threatened species. [ABSTRACT FROM AUTHOR]

Mustard is a commercial oilseed crop worldwide infected by a highly infectious turnip mosaic virus (TuMV). In the experimental field at ICAR-IARI, New Delhi, in 2022, a 100% incidence of TuMV infection was observed in brown, black and yellow mustard. A very low aphid population suggested the possibility of seed transmission. Earlier, the virus genome was characterized by high throughput sequencing and it was a recombinant of World-B and Asian-BR isolates. The presence of TuMV in immature seeds was confirmed in eight field-grown genotypes via RT-PCR using CP-specific primers designed from the same genome sequence. TuMV was found to be localized in embryo and cotyledon, indicating its true seed-borne nature. Presence of TuMV was also confirmed by RT-PCR in the grow out plants from seeds of field grown eight infected genotypes and 9 genotypes collected from seed stock, that were grown in an aphid-free growth chamber. Further, out of 24 seedlings of Pusa Gold (seed stock) and Pusa Karishma (seeds from field grown plants), 20 and 17 seedlings were found infected with TuMV, respectively. The internally seed-borne nature of the virus leads to its early establishment at the seedling stage, leading to stunting and leaf-puckering symptoms in the progeny plants. This study is the first evidence of seed embryo infection and seedling transmission of TuMV of all the three species of mustard plants (brown, black and yellow mustard). Seed transmission of TuMV in mustard genotypes have implications for the seed exchange programme of mustard seeds. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Maize is the world's second most important agricultural crop. The cereal was unknown to Europeans before the end of the 15th century, but since its arrival in Europe, it has changed agriculture, food and landscapes. Terraces where maize was cultivated in the Northwest of the Iberian Peninsula contributed to the formation of local cultures and identities. The history of maize and maize landscape are mementos that help to recover traditional practices, fostering identities, and are crucial for the successful implementation of sustainable policies to provide prosperous futures. Summary: Maize (Zea mays L.) in the Iberian Peninsula embodies a history of landscape changes where the concepts of 'exotic', 'traditional' and 'hybrid' help to understand the engagements between landscape, farmers, agronomists (since the 19th and 20th centuries) and seeds. Today, landscapes reveal biophysical and ecological changes that reflect a panoply of intentions. A multitude of agents, and their interactions, acted upon those territories over time.Using historical sources from the leading institutions dedicated to agricultural research in the Iberian Peninsula, this paper aims to (1) contribute to a better understanding of the maize landscape and culture in the Iberian Peninsula and (2) interrogate how landscape changes (and the landscape history of maize) can frame local or regional heritage and identities reflecting customs or ways of life.The analysis unveils networks of knowledge, agricultural technologies and seed exchange. Politicians, economists, engineers, agronomists, farmers, governmental officials and agricultural industries planned and transformed traditional rural practices into modern and industrialised ones. Experts and politicians, willing to improve agricultural practices and seeds, using hybrid seeds or building new irrigation systems, led to deep social and landscape changes, allowing maize to cover territories far away from its traditional domains. Moreover, despite farmers' resistance, hybrid maize substituted landraces, eroding agrobiodiversity. Nowadays, the south and east regions of the Iberian Peninsula are the main producers of maize (hybrid), whereas in the Northwest maize is an occasional crop, being replaced by vineyards for economic reasons. [ABSTRACT FROM AUTHOR]

Despite the Green Revolution's impact, many small-scale farmers continue cultivating landraces for their agronomic, culinary, and cultural values. This study, conducted in Odisha, focuses on region-specific on-farm conservation practices employed by farmers for landraces. Five focused group discussions were conducted in five villages, involving 15 landrace custodian farmers in each village of Western districts of Odisha. The Four-Square Analysis, a participatory approach, was utilized to evaluate landrace conservation practices in five villages. Principal Component Analysis and Biplot visualization were employed to analyze the relationships between practices, varieties, and conservation scores. Focused group discussion revealed that a total of 30 paddy landraces were cultivated and conserved in the sampled villages. The study identified diverse landraces such as Kalabati, Katia, and Kusum kali, each valued for unique traits and cultural significance. Paddy landraces with disease resistance, medicinal value, and economic significance were commonly cultivated in households or on a larger scale. Important agronomic practices involved organic farming, reduced fertilizer use, biological pest control, System of Rice Intensification (SRI), and bacterial culture for landrace conservation. Management practices comprised seed banks, diversity blocks, seed exchanges, and community cultivation. The findings highlight the importance of farmers' indigenous knowledge, their beliefs and cultural practices in conserving landraces. Landraces which were rare and cultivated due to cultural or social importance require special attention in conservation efforts. Incentivizing community involvement and implementing tailored strategies would be crucial for effective landrace conservation initiatives. [ABSTRACT FROM AUTHOR]

Cinnamomum cassia (L.) J.Presl, a tropical aromatic evergreen tree belonging to the Lauraceae family, is commonly used in traditional Chinese medicine. It is also a traditional spice used worldwide. However, little is currently known about the extent of the genetic variability and population structure of C. cassia. In this study, 71 individuals were collected from seven populations across two geographical provinces in China. Nine morphological features, three chemical components, and single nucleotide polymorphism (SNP) markers were used in an integrated study of C. cassia germplasm variations. Remarkable genetic variation exists in both phenotypic and chemical compositions, and certain traits, such as leaf length, leaf width, volatile oil content, and geographic distribution, are correlated with each other. One-year-old C. cassia seedling leaf length, leaf width, elevation, and volatile oil content were found to be the main contributors to diversity, according to principal component analysis (PCA). Three major groupings were identified by cluster analysis based on the phenotypic and volatile oil data. This was in line with the findings of related research using 1,387,213 SNP markers; crucially, they all demonstrated a substantial link with geographic origin. However, there was little similarity between the results of the two clusters. Analysis of molecular variance (AMOVA) revealed that the genetic diversity of C. Cassia populations was low, primarily among individuals within populations, accounting for 95.87% of the total. Shannon's information index (I) varied from 0.418 to 0.513, with a mean of 0.478 (Na=1.860, Ne =1.584, Ho =0.481, He =0.325, and PPB =86.04%). Genetic differentiation across populations was not significant because natural adaptation or extensive exchange of seeds among farmers between environments, thus maintaining the relationship. Following a population structure analysis using the ADMIXTURE software, 71 accessions were found to be clustered into three groups, with 38% of them being of the pure type, a finding that was further supported by PCA. Future breeding strategies and our understanding of the evolutionary relationships within the C. cassia population would benefit greatly from a thorough investigation of phenotypic, chemical, and molecular markers. [ABSTRACT FROM AUTHOR]

Species phenology - the timing of key life events - is being altered by ongoing climate changes with yet underappreciated consequences for ecosystem stability. While flowering is generally occurring earlier, we know much less about other key processes such as the time of fruit ripening, largely due to the lack of comprehensive long-term datasets. Here we provide information on the exact date and site where seeds of 4,462 taxa were collected for the Index Seminum (seed exchange catalogue) of the Botanic Garden of the University of Coimbra, between 1926 and 2013. Seeds were collected from spontaneous and cultivated individuals across Portugal, including both native and introduced taxa. The database consists of 127,747 curated records with information on the species, or infraspecific taxa (including authority), and the day and site where seeds were collected. All records are georeferenced and provided with a confidence interval for the collection site. Taxonomy was first curated manually by in-house botanists and then harmonized according to the GBIF backbone taxonomy. [ABSTRACT FROM AUTHOR]

Various agricultural crops are the world's sources of food, fodder, and energy. However, conservation management and diversification constraints remain a challenge. Therefore, the present study aimed to assess the status of local agricultural sorghum genetic diversity and potential determinants of the Wollo lowlands in northeastern Ethiopia. The greatest extent of local sorghum abundance was demonstrated in the study areas with the highest value being 4.25 DMg and 2.89 DMn in Werebabo district. However, 2.97 DMg and 2.04 DMn were recorded as the relatively lowest indices in Tehuledere province. In fact, the extent and type of diversity, measured by the number of varieties per farm, varied from region to region. Farmer perceived constraints such as late maturity, blending fluency, distance to nearest market (km), small land ownership, end‐use quality, and plume size attributed to these deviations. The priority of the constraints was first determined by ranking the constraints based on the answers received from the respondents and then calculating the rank‐based quotient. Several categorical variables of these constraints also showed a significant association with the status of local farm sorghum genetic diversity at p < 0.05 and p < 0.001. In general, the status of genetic diversity of local sorghum farms was low in all the provinces studied. Therefore, the seed exchange network between local farmers should be encouraged to use and conserve diversity on a daily basis. Community seed banks should also be established to enhance the conservation of beneficial local sorghum germplasm and maximize locally adapted sorghum landrace profiles. Core Ideas: The extent of the genetic diversity status of the local sorghum on the farm was estimated in terms of richness and uniformity indices by applying different ecological models.In all areas studied, the level and type of local genetic diversity of sorghum varied from area to area or within a locality.Agricultural communities prioritize various constraints affecting sorghum distribution patterns, cultivation, and crop existence in the study provinces.Based on the answers received from the respondents, rank‐based quotient (RBQ) calculation was performed.The various constraints also showed a statistically significant association with on‐farm local sorghum genetic diversity status at p < 0.05 and p < 0.001. [ABSTRACT FROM AUTHOR]

Raimonds Cinovskis (1930–1998) devoted his entire life to plants, especially to the research of dendroflora in Latvia, as well as in the Baltic states in general, and he also participated in botanical expeditions in several places in Asia. He introduced many new names of plant taxa, described new taxa, and made new name combinations. Although the plant names he created are widely used by Latvian botanists and can also be found in the seed exchange catalogues issued by local botanic gardens, these names have never been (with some exceptions) evaluated before. This paper summarises all of the names of plant taxa introduced by R. Cinovskis. It was established that R. Cinovskis introduced more than 200 new names of plant taxa or new name combinations for plants belonging to 11 plant families — Betulaceae, Caprifoliaceae, Cupressaceae, Grossulariaceae, Juglandaceae, Pinaceae, Ranunculaceae, Rosaceae, Salicaceae, Sapindaceae, and Ulmaceae. The majority of the names of plant taxa were for plants of the rose family (Rosaceae). Critically evaluating the compliance of the names introduced by R. Cinovskis with the International Code of Nomenclature for algae, fungi, and plants, it was concluded that the majority of the names were published illegitimately. [ABSTRACT FROM AUTHOR]

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Societal Impact Statement: Crop seed exchange networks, shaped by social dynamics, strongly influence the organization and breadth of plant diversity in human‐managed environments. Integrating an urban and market perspective, this study explores the diversity dynamics of a socio‐economically important Central African fruit tree species, the African plum tree. Tree owners in urban, peri‐urban and rural sites use seeds from different origins as their main propagation material, leading to locational variations in genetic diversity and structure. This analysis contributes toward building a framework to inform the research agenda of cultivated African fruit trees, by highlighting the important role of urban centers in safeguarding crop genetic resources. Summary: Biocultural factors constrain the dynamics of crop species diversity. Here, we considered different aspects of the social, spatial and temporal dynamics of morphological and genetic diversity in a multi‐purpose perennial crop, the African plum tree (Dacryodes edulis). We assessed (i) how seed exchange networks were organized along urbanization gradients, and how they influenced the distribution of species diversity; (ii) the temporal dynamic of seed exchange network by characterizing species genetic diversity through time.To do so, the study was carried out in Cameroon, where we focused on three urbanization gradients, covering urban, peri‐urban and rural areas, corresponding to three different ethnic groups (Bamileke, Bassa, Beti). We combined interviews with tree owners and nuclear microsatellite‐based genetic analyses.Tree owners from urban and peri‐urban sites primarily used distant seed sources, acquired in the market or from their village of origin, as propagation material, whereas tree owners in rural sites relied primarily on village‐level seeds. In turn, genetic diversity was not evenly distributed, with rural sites exhibiting their own genetic clusters. On the contrary, the genetic diversity of urban sites was enhanced by extensive human‐mediated seed flows. Looking at trees from different age classes, we found that genetic diversity was stable over time.Overall, this first attempt to combine different levels of diversity for African plum trees in commercially connected areas expands the scope for in situ intraspecific conservation by highlighting the contribution of urbanized areas. [ABSTRACT FROM AUTHOR]

Copyright of Universitas Scientiarum is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chenopodium quinoa is an Andean species of great interest because of its excellent nutritional quality and great adaptability to different environmental conditions. In addition, the high phenotypic diversity has caused difficulties in the correct taxonomic identification, and there are few studies on the phylogenetic relationships of quinoa in Colombia. Therefore, the objective of this research was to determine the phylogenetic relationships of quinoa with the matK and rcbL chloroplastid genes to characterize the genetic diversity in Colombian quinoa. Evolutionary analyses were performed using nucleotide substitution rates, pattern, base composition, and phylogeny construction. The rbcL gene presented approximately 1344 bp, and matK had 646 bp, which were translated into 434 and 215 amino acids, respectively. The nucleotide composition of the genes showed high percentages of similarity and identity with the Chenopodium quinoa sequences registered in GenBank and BOLD. Similar phylogenetic trees were obtained with the rbcL and matK genes, and both concatenated sequences grouped the accessions into clades. The results showed that Colombian quinoa has low rates of genetic differentiation that may be due to the domestication processes of the species, the lack of certified seeds, and the constant exchange of seeds between farmers in the principal producing areas of the Andean region. [ABSTRACT FROM AUTHOR]

Macrocyclic lactone anthelmintics are widely used to control invertebrate pests in livestock, such as sheep. While anthelmintic effects on non‐target animals, such as dung‐dwelling insects, are well studied, effects on seed germination are largely unknown. Seeds can come into contact with anthelmintics either during passage through the gastro‐intestinal tract of grazing animals or when anthelmintics are excreted with their dung into the environment, which may result in changed germination patterns.We used four commonly applied macrocyclic lactones to assess their effects on germination: moxidectin, ivermectin, abamectin and doramectin as pure substances; moxidectin and ivermectin also in formulated form. We tested these pharmaceuticals on 17 different temperate grassland species from five plant families. Seeds were exposed to three concentrations of macrocyclic lactones (0.1, 1.0 and 10.0 mg·l−1) under controlled conditions, and germination was assessed over a 6‐week period. From these data, we calculated germination percentage, mean germination time and germination synchrony.Most of the tested species were significantly affected in germination percentage and/or mean germination time by at least one of the tested pharmaceuticals, with formulated moxidectin having the largest impact. In general, the effects found were species‐ and pharmaceutical‐specific. While formulated substances generally reduced germination percentage and increased mean germination time, pure substances increased germination percentage. Synchrony showed less clear patterns in all pharmaceuticals.Although effect size and sign varied between species, our study shows that non‐target effects of macrocyclic lactones commonly occur in terrestrial plants. This may impede successful seed exchange between habitats via sheep, and even translate into profound changes to grazed ecosystems. [ABSTRACT FROM AUTHOR]

Diversity is essential to climate resilience in food and farming. Traditionally, agrobiodiversity has been cultivated and sustained through communities' relationships with seeds. A fluid process of saving, preserving, and exchanging seeds allows for regional adaptation and transformation. This process results in seed diversity at the crop, variety, and genetic level. Over the last century, agrobiodiversity has declined at an alarming rate, and simultaneously there has been an erosion of community seed-keeping practices. A reaction to these interrelated crises has been an increased push to preserve biodiversity through institutional seed preservation efforts (also called ex situ preservation), which focus on genetic preservation of seeds in controlled environments. The seeds are genetic resources that are made available to plant breeders, who solve agronomic problems by creating improved cultivars for farmers. This is very different from community seed-keeping (also called in situ preservation), which values seed-people relationships and fosters natural agrobiodiversity and regional adaptation. Seeds are seen in direct connection to food, and saved for immediate and practical reasons like yield, flavor, and resistance to biotic stressors. In traditional communities, seeds are often perceived as kin, as ancestors or living beings with both histories and futures. For institutional seed preservation, collecting and maintaining seed diversity is an imperative insurance policy against future challenges. Ironically, this model erodes community-based seed-keeping efforts and increases dependence on institutional seed preservation to maintain genetic diversity. In this paper, we explore declining agrobiodiversity and community seed-keeping and share our experiences working with a diverse range of varieties from The Heirloom Collard Project (HCP). We propose that radical seed diversity can jump-start autonomous, community-based seed-keeping efforts, increasing agrobiodiversity and, ultimately, the climate resilience of food systems. [ABSTRACT FROM AUTHOR]

Seed exchanges that smallholder households perform form networks that are central to in situ agrobiodiversity conservation. Sociodemographic factors such as market accessibility and household assets could be shaping the structure of these networks and impacting diversity, however formal evidence is scarce. Through surveys in nine rural communities in the Cofre de Perote highland region in Mexico, we modeled seed exchange networks for native maize and conducted a social network analysis followed by statistical modeling. Results show that access to urban centers is negatively related to the robustness of community networks. Within communities, households with bigger plots, more time producing, sufficient maize for self-consumption, and fewer members were able to save seeds for the next cropping season and were more likely to donate seeds. Additionally, households that exchanged more produced more maize morphotypes. We conclude that the maize seed networks under study are serving as seed reservoirs for families in case of scarcity, thus contributing to food security. They are also important for in situ agrobiodiversity conservation of six maize morphotypes. However, it is necessary to promote seed exchanges between households of communities with more access to urban centers, to strengthen networks, and preserve their maize diversity and seed scarcity-dampening function. [ABSTRACT FROM AUTHOR]

Characterisation of genetic diversity is critical to adequately exploit the potential of germplasm collections and identify important traits for breeding programs and sustainable crop improvement. Here, we characterised the phenotypic and genetic diversity of a global collection of the two cultivated buckwheat species Fagopyrum esculentum and Fagopyrum tataricum (190 and 51 accessions, respectively) using 37 agro-morphological traits and 24 SSR markers. A wide range of variation was observed in both species for most of the traits analysed. The two species differed significantly in most traits, with traits related to seeds and flowering contributing most to differentiation. The accessions of each species were divided into three major phenoclusters with no clear geographic clustering. At the molecular level, the polymorphic SSR markers were highly informative, with an average polymorphic information content (PIC) of over 0.65 in both species. Genetic diversity, as determined by Nei's expected heterozygosity (He), was high (He = 0.77 and He = 0.66, respectively) and differed significantly between species (p = 0.03) but was homogeneously distributed between regions, confirming the lack of genetic structure as determined by clustering approaches. The weak genetic structure revealed by the phenotypic and SSR data and the low fixation indices in both species suggested frequent seed exchange and extensive cultivation and selection. In addition, 93 and 140 significant (p < 0.05) marker-trait associations (MTAs) were identified in both species using a general linear model and a mixed linear model, most of which explained >20% of the phenotypic variation in associated traits. Core collections of 23 and 13 phenotypically and genetically diverse accessions, respectively, were developed for F. esculentum and F. tataricum. Overall, the data analysed provided deep insights into the agro-morphological and genetic diversity and genetic relationships among F. esculentum and F. tataricum accessions and pointed to future directions for genomics-based breeding programs and germplasm management. [ABSTRACT FROM AUTHOR]

In this paper, I use deconstructive theory to analyze the category of "millet" and the endangerment of food grains in India. I argue that "millet" cohered as a sign of difference from the 1960s through India's Green Revolution, which created a national infrastructure for the materialization of colonial and masculinist ideology. In the hills of Uttarakhand and through the food grain regionally known as mandua, we see how India's postcolonial success relied on the ontological-epistemic erasure of women's food/land practices and assaulted the intertwined "rootedness" (place-making faculties) of women and the crops they cultivate. Reading mandua as "millet" under erasure (millet) reveals how mixed crop systems and practices of socio-ecological reciprocity eroded in the face of Green Revolution ideology and functioned as a bulwark against it. I turn finally to the counterhegemonic potential of "millet," as Uttarakhandi seed activists link with decentralized third world networks, which are exchanging seeds and building power across and from marginalized places. This opens a potential space of visibility and belonging for Uttarakhandi women farmers in the national arena at a time when the ecological and alimentary value of "millet" has entered national and global conversations, infusing the sign of difference with new meaning. [ABSTRACT FROM AUTHOR]

The study tracks the utilization of Ocimum basilicum L. (sweet basil)—a garden plant popular for its ritual and ornamental value in the past, that is currently applied in various forms and ways as medicine, food, insect repellent, etc.—in Bulgaria. Previous data for Bulgarian rural home gardens showed a significant number of preserved local landraces; however, it remained unclear how people perceive the large varietal diversity of this species and how the traditions related to its use are preserved. We combined a literature review on the cultural value of sweet basil and the breeding of local genetic resources with an online questionnaire, directed to adult laypeople, that sought to access different aspects of past (recalled) and present use and related knowledge. The identification skills of the participants were tested using images of local plant landraces and foreign varieties. Responses from 220 participants showed that potted "Genovese"-type individual was most frequently identified as sweet basil (89.9%), followed by two examples of local landraces in flower. Participants who grow sweet basil or used it in more varied ways had significantly better identification skills. Ocimum basilicum was most frequently reported as food, while ritual/symbolic use was preserved while devalued during the Communism regime (1945–1989). Food and religious uses were negatively associated in the past, but presently, the tendency is completely reversed. Preferences for the informal exchange of seeds and seed-saving practices were discussed. [ABSTRACT FROM AUTHOR]

Barley is an important feed crop in Iran and is threatened by an increased frequency of drought. Increasing diversity in the form of evolutionary populations (EPs) and mixtures is one strategy to increase the resilience of crops. Four barley EPs, which have evolved in different locations over 7 to 10 years from the same original population, were evaluated for agronomic trait and stability together with two landraces, and one improved variety for three cropping seasons in four locations. Modest but significant differences were found only for plant height with a range of less than 4 cm. Stability, measured with cultivar superiority, as well as environmental variance and reliability measures generally indicated a superior stability of EPs—with two of them ranking first and second for grain yield reliability—but also differences between the EPs. The effect of recurrent droughts on the diversity within EPs is discussed as a possible explanation for the lack of divergent evolution. The seed management of Eps, including seed exchange between farmers, is suggested as a possible strategy to avoid the reduction in diversity within populations. Future research will address the nutritional value of the EPs, which is often quoted by sheep owners as superior to commonly grown varieties. [ABSTRACT FROM AUTHOR]

In this work, we present an anisotropic generalization of the Buchdahl static stellar model by implementing the method of extended gravitational decoupling and further requirement of vanishing complexity (Herrera, Phys Rev D 97:044010,2018). Starting off with a general spherically symmetric static metric with two unknown gravitational potentials, we impose the condition of vanishing complexity which then reduces the problem to a single‐generating metric function [Contreras and Stuchlik, Eur. Phys. J. C (2022) 82:706]. The Buchdahl ansatz is then employed to obtain the complete gravitational behavior of the isotropic seed solution. The method of extended gravitational decoupling is thereafter utilized to obtain an anisotropic counterpart of the Buchdahl perfect gravitating sphere. We subject our solution to rigorous physical tests to ensure that it serves as a viable candidate for compact objects such as neutron stars as well as pulsars. We show that the decoupling parameter plays a crucial role in determining the stability and regularity of several key physical features of the entire stellar model. A novel finding of our investigation is the energy exchange between the seed solution and the secondary source which we show is sensitive to the decoupling parameter. In addition, it has also been shown that the direction of energy flow depends on the radial distance of the shell from the center of the stellar configuration. [ABSTRACT FROM AUTHOR]

Proper understanding of the nature of seed exchange among farming communities is fundamental to achieving a sustainable seed system and maintaining crop genetic resources. The objective of this study was to investigate sorghum (Sorghum bicolor) seed sources and analyse their network flow among farmers in Tigray in Northern Ethiopia. A survey was conducted using a semi-structured questionnaire, involving 153 sorghum household farmers selected randomly from six villages; namely Gezaadara, Medabe, Gezameker, Waekel, Munira and Gandostela. Farmers who plaid major roles in the sorghum seed exchange network were identified using social seed network analysis. Results showed that bartering and own-saved seeds were the dominant sources of sorghum seed for farmers throughout the study area; and sorghum seed flow was more confined within villages than beyond. Social capital such as cultural norms, trust and farmers' desire to increase sorghum production in the communities were the fundamental drivers for farmer sorghum seed exchange. Individuals distinguished as nodal farmers who had high bridging roles could also act as entry points for improved sorghum seed exchange interventions in Tigray. [ABSTRACT FROM AUTHOR]

Mexico harbors over 50% of maize's genetic diversity in the Americas. Native maize varieties are actively managed by small-scale producers within a diverse array of cultivation systems. Seed lot use, exchange and admixture has consequences for the in situ conservation of such varieties. Here we analyze native maize seed management dynamics from 906 small-scale producers surveyed in three Mexican states: Mexico City, Oaxaca and Chiapas. Furthermore, we analyze how their management practices can relate to transgene presence, which was experimentally documented for maize samples associated with the applied surveys. Through a data mining approach, we investigated which practices might be related with a higher probability of transgene presence. The variables found to have a strong spatial association with transgene presence were: for Mexico City, maize producers with larger parcels; for Oaxaca, producer's age (43–46 years) and the sale of seed; for Chiapas, the use of agricultural machinery and younger producers (37–43 years). Additionally, transgene presence and frequency within the socioeconomic regions of Oaxaca and Chiapas was analyzed. In Oaxaca, higher transgene frequencies occurred in regions where transgene presence had been previously reported. In Chiapas, the border regions with Guatemala as well as a region where reproduction of improved seed takes place, the highest proportion of positive samples were found. A detailed mapping of regional seed markets and seed exchange sites together with deployment of national and local biosecurity measures, could help prevent the further spread of transgenes into native maize varieties, as well as improve conservation efforts. [ABSTRACT FROM AUTHOR]

Returning to Earth's safe operating space requires driving social–ecological transformations toward a new human–nature configuration, while navigating changes and creatively dealing with crises. Family farms in the Colombian Andes have been navigating changes by using modalities of integrated management that recognize family interdependence with nature, which illustrates social–ecological resilience on a small scale. We potentiated family farming by creating FiNCO (Farms for knowledge exchange) as a strategy that renews the connection between disciplines, academia and farmers, and the rural and urban sectors, in order to promote knowledge co-production and landscape stewardship. In this sense, FiNCO is considered as a seed for a good Anthropocene. This paper is an invitation to plant FiNCO seeds in different social–ecological contexts and to share those experiences as an ideal way to create abilities to transform the upcoming humanity challenges into opportunities for humanity's needed transformation. [ABSTRACT FROM AUTHOR]

The study evaluates the cluster front line demonstrations (CFLDs) conducted under the national food security mission on sesame (RT-351) by 26 KVKs of Rajasthan state. Four thousand one (4001) partner farmers responded to the study during 2016-2020. The CFLDs were undertaken in a 172.00 ha area in 26 districts during these five years. Yield gaps and technology index were calculated under the study. The result shows an extension gap of 1.35 q ha-1 and a technology gap of 2.78 q ha-1. The technology index was found to be 35.11 per cent, while a yield advantage of 36.17 per cent was found in CFLDs. KVKs of Rajasthan state could add Rs. 1.45 crores to the income of partner farmers. The improved variety & better extension services significantly enhanced production and productivity. Participatory approaches in the sesame seed supply chain and institutional linkage were critical for scaling up sustainable technology and improving farmers' access to quality and sufficiently improved seeds. More capsules per plant and resistance to stem & root rot attracted the farmers. Technical backstopping, supplying of seed, and seed exchange through farmer-to-farmer extension were crucial on a sustainable basis. Regular monitoring by experts and farmers' feedback is vital for sustained production and productivity improvement of the sesame crop. [ABSTRACT FROM AUTHOR]

Mexico is the center of origin of maize and one of the phenomena that imperil maize conservation is transgene presence. Although previous studies have documented transgene presence in Mexican landraces, to date there is no countrywide transgene monitoring protocol, nor systematic analyses assessing which factors could be related with transgene presence and dispersal. In this work, we propose a geographically representative sampling protocol and present empirical data from three sampled states: Mexico City, Oaxaca and Chiapas. To further investigate which environmental and social variables could be associated with transgene presence, we carried out a data mining approach. To assess transgene presence in collected maize samples, we used Real-Time PCR, finding that transgenes were widely distributed across sampled localities: 33% of the localities in Chiapas, 25% in Mexico City and 11% in Oaxaca. The data mining approach allowed us to identify state-specific spatial associations in Chiapas and Oaxaca. In Chiapas, a higher probability of transgene presence appeared related to the coexistence of industrialized maize agriculture, while in Oaxaca it was related with seed exchange. We discuss the importance of implementing a national biomonitoring protocol to increase our understanding of the sources that enable transgene presence and dispersal. [ABSTRACT FROM AUTHOR]

Endosperm–embryo development in flowering plants is regulated coordinately by signal exchange during seed development. However, such a reciprocal control mechanism has not been clearly identified. In this study, we identified an endosperm‐specific gene, LBD35, expressed in an embryonic development‐dependent manner, by a comparative transcriptome and cytological analyses of double‐fertilized and single‐fertilized seeds prepared by using the kokopelli mutant, which frequently induces single fertilization events. Transcriptome analysis using LBD35 as a marker of the central cell fertilization event identified that 141 genes, including 31 genes for small cysteine‐rich peptides, are expressed in a double fertilization‐dependent manner. Our results reveal possible embryonic signals that regulate endosperm gene expression and provide a practicable method to identify genes involved in the communication during endosperm–embryo development. [ABSTRACT FROM AUTHOR]

Cowpea planting season is crucial for high yield and should comprise the period of the year that warrants the best climatic conditions for cowpea cultivation. Thus, the objective of this study was to evaluate the influence of water availability and temperature on the performance of cowpea cultivars. A greenhouse experiment was conducted using a 4 × 2 × 5 factorial arrangement, with four replications. Factors included four levels of soil moisture (25, 50, 75, and 100% of water holding capacity), two growing seasons (mild and hot), and five cowpea cultivars (Carijó, Itaim, Pujante, Rouxinol, and Tapahium). The number of pods and seeds per plant, seed production, water use efficiency, shoot dry mass, root dry mass, and physiological parameters were evaluated. Seed production was higher during the mild season than during the hot season and increased linearly with increasing soil water availability. Photosynthetic activity and transpiration were higher during the hot season than during the mild season, with their reduction under a water availability of 25% regardless of the growing season. Total chlorophyll content decreased with excess water. Regardless of water availability, temperature was the most limiting climatic factor for cowpea performance. Cultivars Carijó, Itaim, and Tapahium exhibited a lower reduction in productive potential when grown in the hot season. [ABSTRACT FROM AUTHOR]

Agrobiodiversity including landraces of crops is extreme significant for global food security and sustainable rural development but it is losing at alarming speed. Only in the remote areas, some of landraces are remained in local agroecosystem. Landraces refer to the traditional resources domesticated by people living in a certain area. They are bred or evolved in the local environments, which can adapt to the local natural and cultural environments. Changmaogu is a unique colored rice landrace planted by Lama people, a branch of Bai, in Lanping Bai and Pumi Autonomous County, Yunnan Province. Changmaogu is a typical representative landrace in China. Due to its lower yield, the cultivation of Changmaogu was controlled in a very limited area in the past few years, which was a very dangerous signal for a major crop. Despite its rare and endangered status, there has been a lack of research on Changmaogu. In order to promote the conservation and sustainable development of this landrace, we investigated and analyzed the quality traits, traditional knowledge and culture, development and utilization status and existing problems of Changmaogu in Lanping, and determined the nutritional components of Changmaogu comparing with those of common rice varieties to explore the nutritional value of Changmaogu, using the methods of ethnobotany and nutrition. The results are as follows:(1)The Lama people, have developed rich traditional knowledge about Changmaogu, including traditional farming knowledge, relevant historical allusions, traditional eating knowledge, seed exchange and conservation culture. They never use chemicals but collect green manures as fertilizer for this landrace. Under the backgrownd of understanding the good characteristics of Changmaogu, the local people continue to grow Changmaogu in the original habitat in a larger scale according to their traditional knowledge and culture.(2)Changmaogu has a high content of available carbohydrates, water, ash, total dietary fiber and anthocyanin, and contains a certain content of procyanidins, indicating that it has excellent nutritional and health care values. This study indicates that the mode of in-situ or on-farm conservation of Changmaogu provides a great reference for the conservation of other landraces, and reveals the fact that the outstanding properties like high nutritional value of Changmaogu will contribute to the sustainable uses of Changmaogu and other landraces. [ABSTRACT FROM AUTHOR]

Due to war conditions, the local farmers had to largely rely on their own crop production, mainly by subsistence farming, in Tigray, North Ethiopia. We assessed the crop stands in 2021 and evaluated the level of resilience of the indigenous farming system. Quantitative data were collected from 161 farm parcels in various ecoregions of this tropical mountain region, in order to detect the share of sown land, crop types, and their status. This participatory monitoring was accompanied by semi-structured interviews. Farmers cultivated their farms late, left it uncultivated or marginally sowed oil crops as improved fallow (28%), due to lack of farming tools, oxen, fertilizer, seeds, or manpower. As compared to peace years, only few lands were sown with sorghum as there was active warfare in the sorghum planting period. The relatively good stands of wheat and barley (47%) are in line with the farmers' priority given to cereals. Teff got a large land share because it could be sown up to the middle of the main rainy season and because farmers had consumed the seeds of their major cereal crops (wheat and barley) when hiding for warfare. Seeds left from consumption were only sown by late June, when troops had retreated, and the communities could revive. With almost no external support, the local farming system has proven to be remarkably resilient, relying on indigenous knowledge and local practices, block rotation, manure, improved fallow, changes in relative importance of crops, seed exchange, and support for one another. This is the first analysis of the socio-agronomic roots of the 2021–2022 Tigray hunger crisis, with a cereal harvest that could not at all sustain the local population as the planting season had been largely missed. The ability of the indigenous farming system to partially rebounce in times of autarky is another novel finding. [ABSTRACT FROM AUTHOR]

Based on a concept for demand-orientation in seed systems, we characterized Nigeria's cassava (Manihot esculenta) seed system from national to local level and farmers' demand in three study sites. Interviews with seed-system actors explained their roles for supply-side functions. Focus group discussions and a survey described multiple aspects of farmers' demand. Our findings show that the national agriculture development program alone did not have the capacity to supply farmers with sufficient seed of desired varieties. Seed exchange between farmers and informal seed sellers contributed to the distribution of seed and new varieties. The presence of seed sellers and farmers' demand for cassava seed varied between the three study sites, farmer types and gender. We conclude that informal seed sellers and village seed entrepreneurs have a potential to respond to farmers' heterogeneous demands. However, without recurrent demand for specialized seed production or continuous support from the formal system, they do not reach underserved markets. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has motivated a turn towards more agroecological food production and food sovereignty. This article aims to analyze how the agroecological actor network has emerged in and around the capital of Buenos Aires and the province of Santa Fe, in Argentina, during the pandemic. The research questions are: How has the agroecological actor network emerged during the pandemic in Argentina? In what ways are agroecological networks enacted through coupling and decoupling practices? The study is based on interviews with practitioners, and observations of online events. In our results, we show how the production of compost, exchange of seeds and experiences, governmental programs, and food fairs are coupled and assembled in the agroecological network. The agroecological network is decoupling from the conventional agroindustrial model with pesticides and chemical input, supermarkets, and the global food system. The conclusion is that the pandemic has worked as a crisis where the agroecological network has been expanded. [ABSTRACT FROM AUTHOR]

Maintaining duplicate germplasms in genebanks hampers effective conservation and utilization of genebank resources. The redundant germplasm adds to the cost of germplasm conservation by requiring a large proportion of the genebank financial resources towards conservation rather than enriching the diversity. Besides, genome-wide-association analysis using an association panel with over-represented germplasms can be biased resulting in spurious marker-trait associations. The conventional methods of germplasm duplicate removal using passport information suffer from incomplete or missing passport information and data handling errors at various stages of germplasm enrichment. This limitation is less likely in the case of genotypic data. Therefore, we developed a web-based tool, Germplasm Duplicate Identification and Removal Tool (G-DIRT), which allows germplasm duplicate identification based on identity-by-state analysis using single-nucleotide polymorphism genotyping information along with pre-processing of genotypic data. A homozygous genotypic difference threshold of 0.1% for germplasm duplicates has been determined using tetraploid wheat genotypic data with 94.97% of accuracy. Based on the genotypic difference, the tool also builds a dendrogram that can visually depict the relationship between genotypes. To overcome the constraint of high-dimensional genotypic data, an offline version of G-DIRT in the interface of R has also been developed. The G-DIRT is expected to help genebank curators, breeders and other researchers across the world in identifying germplasm duplicates from the global genebank collections by only using the easily sharable genotypic data instead of physically exchanging the seeds or propagating materials. The web server will complement the existing methods of germplasm duplicate identification based on passport or phenotypic information being freely accessible at http://webtools.nbpgr.ernet.in/gdirt/. [ABSTRACT FROM AUTHOR]

Seed system network analysis can reveal exchange connections between stakeholders and test scenarios such as those of seed systems shocks. We investigated the seed exchange network structure, disease surveillance risk, and gender contribution in Burundi, under two banana disease risk scenarios. Two sites where banana bunchy top disease (BBTD) is endemic in Cibitoke Province were compared with a site free of the disease in Gitega Province. All sites had formal seed interventions using community nurseries. A quantitative survey on seed sharing was done followed by a qualitative evaluation through focus group discussions. Banana seed sourcing options were fewer in the disease-free site, which also had higher cultivar diversity. Most farmers sourced seed informally within a three-kilometer radius. Seed sharing within and between villages was based on social and family linkages, especially for women. The interaction between the formal system and informal seed exchange was more active where new cultivars, or better seed quality was expected. The BBTD endemic region had lower seed quality assessment stringency. Farmers used both direct mother plant assessment and seed source reputation in seed evaluation. The formal banana seed systems are sources of new varieties, and trusted for clean seed but the informal system was still used as a main source of seed, especially local cultivars. Assessing disease surveillance scenarios shows women in a weaker position for healthy seed acquisition. Identifying the roles of individuals in seed systems can support decision processes for seed interventions in vegetatively propagated crops. [ABSTRACT FROM AUTHOR]

Underwater wireless acoustic networks (UWANs) take advantage of acoustic communication to enable many distinct applications. The peculiar features of underwater acoustic channels, such as long propagation delay, high bit error rates, and severely limited bandwidth, make the use of medium access control (MAC) solutions designed for terrestrial radio networks inefficient in UWANs. This paper proposes UW-SEEDEX, a MAC protocol for UWANs that employs random time slot schedules, created from seeds, to avoid collisions. After exchanging seeds, nodes can know other’s entire schedules, allowing them to then better plan their transmissions. Simulations evaluate how each of UW-SEEDEX’s parameter affects its performance in metrics such as end-to-end delay, energy consumption, transmissions per data reception, and reception rate using different test scenarios. Simulations also show that UW-SEEDEX can perform better than other MAC solutions, delivering more messages than protocols such as UW-Aloha and Slotted FAMA and reduced, on average, up to three times the number of transmissions required for each message reception in networks with grid topologies. UW-SEEDEX presented reception rates close to 100 percent, low energy cost, and fewer transmissions per data reception. Our code is available at https://gitlab.com/epmcj/ns-3-dev/-/tree/new-uan-mac-protocols. [ABSTRACT FROM AUTHOR]

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Crop diversity results from farmers' selection and exchange of seeds. The crop diversity erosion observed over the last century can be attributed to the transition from traditional to industrial farming practices. Farmers' seed varieties have been replaced by a few privately owned, high-yielding varieties. The resulting uniformity is jeopardizing food security, further exacerbated by climate change. Both the international framework and the EU legislation perpetuate the root cause of crop diversity erosion. The EU only authorizes on the internal market varieties that are distinct, uniform, stable, and of 'satisfactory value for cultivation and use'. Non-complying seeds, meaning traditional heterogeneous varieties, are banned. Furthermore, the few authorized varieties are open to privatization through either a Community Plant Variety Right or patents on biotechnological inventions. The exchange, access, and use of these seeds are strictly restricted. Although the EU provides derogations in certain cases, the legal space created is too narrow to ensure the conservation and sustainable use of plant genetic resources for food and agriculture (PGRFA). [ABSTRACT FROM AUTHOR]

In a graphic illustration of consolidation in the seed industry through 2018, and how corporations control our seeds, Phil Howard tells the story of how farmers have been losing control of their seeds for quite some time (Howard [2]). From a narrowing of the genetic foundation of agriculture to the legal restrictions on the age-old practice of farmers saving their own seed and exchanging it with other farmers, the consolidation of the seed industry in the hands of 4 transnational corporations that Howard has documented is frightening. In a new post that expands this story, Howard shows how this consolidation continued to intensify just over the past 4 years, and not only involves seeds, but has now begun to capture data technology (Strömberg and Howard [7]). [Extracted from the article]