Determination of α-methylenecyclopropylglycine in Shahi and China litchi cultivars at three different maturity stages: A quantitative study using liquid chromatography tandem mass spectrometry.

This study presents the contents of α-methylenecyclopropylglycine, a potentially toxic amino acid, in the peel, pulp and seed fractions of two well-known litchi varieties, namely Shahi and China, over a span of three harvest-seasons. For analysing α-methylenecyclopropylglycine, an LC-MS/MS-based method was validated. The method-accuracies fell within 75-110 % (RSD, <15 %) at 0.1 mg/kg (LOQ) and higher levels. A comparative evaluation of the results in peel, pulp and seed at 30 days before harvest (DBH), 15-DBH, and edible-ripe stage revealed that α-methylenecyclopropylglycine content increased as the litchi seeds grew towards maturity, regardless of the cultivar. In arils, at maturity, the concentration of α-methylenecyclopropylglycine ranged from not-detected to 11.7 µg/g dry weight. The Shahi cultivar showed slightly higher α-methylenecyclopropylglycine content in comparison to China litchi. This paper presents the first known analysis of combined seasonal data on different fruit components at various growth stages for the two chosen litchi cultivars grown in India.

Functional Diversification of Sec13 Isoforms for Storage Protein Trafficking in Rice Endosperm Cells.

Coat protein complex II (COPII) vesicles play crucial roles in mediating the endoplasmic reticulum (ER) exit of newly synthesized proteins to the Golgi in eukaryotic cells. However, the molecular functions of COPII components and their functional diversifications in plant seeds remain obscure. Here, we showed that the rice (Oryza sativa) glutelin precursor accumulation12 (gpa12) mutant is defective in storage protein export from the ER, resulting in the formation of aggregated protein bodies. Map-based cloning revealed that GPA12 encodes a COPII outer layer protein, Sec13a, that mainly localizes to endoplasmic reticulum exit sites (ERES) and partially localizes to the Golgi. Biochemical experiments verified that Sec13a physically interacts with Sec31 and Sec16, and mutation in Sec13 compromises its interaction with Sec31 and Sec16, thereby affecting the membrane association of the inner complex components Sar1b and Sec23c. Apart from Sec13a, the rice genome encodes two other Sec13 isoforms, Sec13b and Sec13c. Notably, we observed an abnormal accumulation of globular ER structures in the sec13bc double mutant but not in the single mutants, suggesting a functional redundancy of Sec13b and Sec13c in modulating ER morphology. Taken together, our results substantiated that Sec13a plays an important role in regulating storage protein export from the ER, while Sec13b and Sec13c are required for maintaining ER morphology in rice endosperm cells. Our findings provide insights into the functional diversification of COPII components in plants.

Experimental study into the effects of pitch and coning angles on the flight performance of the natural samara.

Using their light wing and through the use of a leading-edge vortex (LEV), autorotating samaras can generate high lift while descending at extremely low speeds. But the flight performance of the samara, with respect to the wide design envelope, is still not well understood. Therefore, this paper aims to experimentally assess how the flight performance of three natural samara wings varies with differing wind speeds and flight conditions. The tests were conducted within a vertical wind tunnel and a novel rig was devised to effectively measure the vertical thrust and rotational rate of the autorotating samara at near frictionless conditions. Furthermore, a bespoke hub was implemented to control the coning and pitch angles of the samara wing. The tests generated a novel and comprehensive set of experimental data of autorotating samaras with changing wind speed, coning and pitch angles. The results also revealed that coning angles between 5 and 15 degrees can increase the vertical thrust produced by the samara by up to a maximum of 9.6 % . Additionally, it was found that samaras operate at extremely low pitch angles between -0.7 and -2.6 degrees to maximise their thrust, even though the conditions are close to the autorotational stability boundary.

Evaluation of cucumber seed germination vigor under salt stress environment based on improved YOLOv8.

Seed germination vigor is one of the important indexes reflecting the quality of seeds, and the level of its germination vigor directly affects the crop yield. The traditional manual determination of seed germination vigor is inefficient, subjective, prone to damage the seed structure, cumbersome and with large errors. We carried out a cucumber seed germination experiment under salt stress based on the seed germination phenotype acquisition platform. We obtained image data of cucumber seed germination under salt stress conditions. On the basis of the YOLOv8-n model, the original loss function CIoU_Loss was replaced by ECIOU_Loss, and the Coordinate Attention(CA) mechanism was added to the head network, which helped the model locate and identify the target. The small-target detection head was added, which enhanced the detection accuracy of the tiny target. The precision P, recall R, and mAP of detection of the model improved from the original values of 91.6%, 85.4%, and 91.8% to 96.9%, 97.3%, and 98.9%, respectively. Based on the improved YOLOv8-ECS model, cucumber seeds under different concentrations of salt stress were detected by target detection, cucumber seed germination rate, germination index and other parameters were calculated, the root length of cucumber seeds during germination was extracted and analyzed, and the change characteristics of root length during cucumber seed germination were obtained, and finally the germination activity of cucumber seeds under different concentrations of salt stress was evaluated. This work provides a simple and efficient method for the selection and breeding of salt-tolerant varieties of cucumber.

Physio-biochemical mechanism of melatonin seed priming in stimulating growth and drought tolerance in bread wheat.

Drought stress (DS) adversely affects a plant's development and growth by negatively altering the plant's physio-biochemical functions. Previous investigations have illustrated that seed priming with growth regulators is an accessible, affordable, and effective practice to elevate a plant's tolerance to drought stress. Melatonin (MT) is derived from the precursor tryptophan and can improve germination, biomass, and photosynthesis under stress conditions. The current study examined the effect of melatonin seed priming on two wheat cultivars (Fakhar-e-Bhakkar and Akber-19) cultivated under severe drought conditions (35% FC). There were 6 levels of melatonin (i.e., M0 = control, M1 = 1 mg L- 1, M2 = 2 mg L- 1, M3 = 3 mg L- 1, M4 = 4 mg L- 1 and M5 = mg L- 1) which were used for seed priming. Our results confirmed that seed priming with M2 = 2 mgL- 1 concentration of MT alleviates the negative effects of DS by boosting the germination rate by 54.84% in Akber-19 and 33.33% in Fakhar-e-Bhakkar. Similarly, leaf-relative water contents were enhanced by 22.38% and 13.28% in Akber-19 and Fakhar-e-Bhakkar, respectively. Melatonin pre-treatment with 2 mgL- 1 significantly enhanced fresh and dry biomass of shoot and root, leaf area, photosynthetic pigments, osmoprotectants accumulation [total soluble proteins (TSP), total free amino acids (TFAA), proline, soluble sugars, glycine betaine (GB)] and lowered the amount of malondialdehyde (MDA) and hydrogen peroxide (H2O2) production by elevating antioxidants [Ascorbic acid, catalase (CAT), Phenolics, peroxidase (POD) and superoxide dismutase (SOD)] activity under drought stress (DS). Meanwhile, under control conditions (NoDS), the melatonin treatment M1 = 1 mgL- 1 effectively enhanced all the growth-related physio-biochemical attributes in both wheat cultivars. In the future, more investigations are suggested on different crops under variable agroclimatic conditions to declare 2 mgL- 1 melatonin as an efficacious amendment to alleviate drought stress.

Transcriptome analysis reveals biosynthesis and regulation of flavonoid in common bean seeds during grain filling.

The Andean domesticated common beans (Phaseolus vulgaris) are significant sources of phenolic compounds associated with health benefits. However, the regulation of biosynthesis of these compounds during bean seed development remains unclear. To elucidate the gene expression patterns involved in the regulation of the flavonoid pathway, we conducted a transcriptome analysis of two contrasting Chilean varieties, Negro Argel (black bean) and Coscorron (white bean), at three developmental stages associated with seed color change, as well as different flavonoid compound accumulations. Our study reveals that phenolic compound synthesis initiates during seed filling, although it exhibits desynchronization between both varieties. We identified 10,153 Differentially Expressed Genes (DEGs) across all comparisons. The KEGG pathway 'Flavonoid biosynthesis' showed enrichment of induced DEGs in Negro Argel (PV172), consistent with the accumulation of delphinidin, petunidin, and malvidin hexosides in their seeds, while catechin glucoside, procyanidin and kaempferol derivatives were predominantly detected in Coscorrón (PV24). Furthermore, while the flavonoid pathway was active in both varieties, our results suggest that enzymes involved in the final steps, such as ANS and UGT, were crucial, inducing anthocyanin formation in Negro Argel. Additionally, during active anthocyanin biosynthesis, the accumulation of reserve proteins or those related to seed protection and germination was induced. These findings provide valuable insights and serve as a guide for plant breeding aimed at enhancing the health and nutritional properties of common beans.

Embryo excision in Compositae, with implications for combating biodiversity loss.

Premise: Embryo excision is an effective, under-described means of promoting germination in the sunflower family and may help to ensure the survival of endangered taxa or lineages with limited seed availability. Methods and Results: We describe and illustrate a detailed method of embryo excision used successfully to stimulate germination in a diversity of composites and that requires minimal materials and expense, using Layia platyglossa as an example. We show how this procedure greatly increases germination compared to control treatments in Madia elegans, a close relative of Hawaiian silverswords that exhibits physiological dormancy. Conclusions: This technique can be learned quickly and is highly effective. Embryo excision can aid conservation efforts dependent on minimal seed resources by enhancing germination and allowing evaluation of seed quality before or after storage, as well as synchronizing seedling development, thereby allowing for refinement of ex situ seed bank conditions and efficient use of horticultural resources.

Premisa: La escisión de embriones es un medio eficaz y poco descrito para promover la germinación en la familia Asteraceae y puede ayudar a garantizar la supervivencia de taxones o linajes en peligro de extinción con disponibilidad limitada de semillas. Métodos y Resultados: Describimos e ilustramos un método detallado de escisión de embriones utilizado con éxito para estimular la germinación en una diversidad de asteráceas y que requiere materiales y gastos mínimos, utilizando Layia platyglossa como ejemplo. Mostramos cómo este procedimiento aumenta en gran medida la germinación en comparación con los tratamientos de control en Madia elegans, un pariente cercano de las silverswords hawaianas que exhibe latencia fisiológica. Conclusiones: Esta técnica se puede aprender rápidamente y es muy eficaz. La escisión de embriones puede ayudar a los esfuerzos de conservación que dependen de recursos mínimos de semillas al mejorar la germinación y permitir la evaluación de la calidad de las semillas antes o después del almacenamiento, así como sincronizar el desarrollo de las plántulas, permitiendo así el refinamiento de las condiciones del banco de semillas ex situ y el uso eficiente de los recursos hortícolas.

The Relationship Between Maturation Size and Maximum Tree Size From Tropical to Boreal Climates.

The fundamental trade-off between current and future reproduction has long been considered to result in a tendency for species that can grow large to begin reproduction at a larger size. Due to the prolonged time required to reach maturity, estimates of tree maturation size remain very rare and we lack a global view on the generality and the shape of this trade-off. Using seed production from five continents, we estimate tree maturation sizes for 486 tree species spanning tropical to boreal climates. Results show that a species' maturation size increases with maximum size, but in a non-proportional way: the largest species begin reproduction at smaller sizes than would be expected if maturation were simply proportional to maximum size. Furthermore, the decrease in relative maturation size is steepest in cold climates. These findings on maturation size drivers are key to accurately represent forests' responses to disturbance and climate change.

A global database of soil seed bank richness, density, and abundance.

A soil seed bank is the collective name for viable seeds that are stored naturally in the soil. At the species or population level, the ability to form a seed bank represents a strategy for (re)colonization following a disturbance or other change in the local environmental conditions. At the community level, seed banks are thought to buffer local diversity during periods of environmental change and are often studied in relation to the potential for passive habitat restoration. The role that seed banks play in plant population and community dynamics, as well as their importance in the agricultural sector, means that they have been widely studied in ecological research. This database is the result of a comprehensive literature search, including all seed bank studies from the Web of Science from which data could be extracted, as well as an additional search of the Russian language literature. The database contains information on the species richness, seed density, and/or seed abundance in 3096 records from at least 1929 locations across the world's seven continents, extracted from 1442 studies published between 1940 and 2020. Records are grouped into five broad habitat categories (aquatic, arable, forest, grassland-including shrubland-and wetland), including information relating to habitat degradation from, or restoration to other habitats (total 14 combinations). Sampling protocols were also extracted for each record, and the database was extensively checked for errors. The location of each record was then used to extract summary climate data and biome classification from external published databases. The database has several potential uses. The large geographical spread relative to many other global biodiversity datasets is relevant for investigating patterns of diversity in biogeographical or macroecological contexts. Habitat type and status (intact, degraded, and restored) can be used to provide insights for biodiversity conservation, while the potential effects of sampling method and effort can be used to inform optimized data collection for future seed bank studies. This database is released under the CC-BY license.

Evolutionary origin and functional investigation of the widely conserved plant PEBP gene STEPMOTHER OF FT AND TFL1 (SMFT).

Genes of the family PHOSPHATIDYLETHANOLAMINE-BINDING PROTEINS (PEBP) have been intensely studied in plants for their role in cell (re)programming and meristem differentiation. Recently, sporadic reports of the presence of a new type of PEBP in plants became available, highly similar to the YY-PEBPs of prokaryotes. A comprehensive investigation of their spread, origin, and function revealed conservation across the plant kingdom. The YY-PEBP clade in plants seems to have resulted from a single Horizontal Gene Transfer (HGT) episode from a prokaryotic organism to an ancestral streptophyte. YY-PEBPs are also present in other eukaryotes, such as certain fungi, diatoms, and rotifers, and these cases derive from independent HGT events. Reciprocally, the occurrence of the eukaryotic CETS/RKIP type PEBPs (CR-PEBPs) was noticed in bacteria of the genus Nocardia, showing that HGT has occurred as well from eukaryotes to prokaryotes. Based on these observations, we propose that the current model of the PEBP family in plants needs to be updated with the clade STEPMOTHER OF FT AND TFL1 (SMFT). SMFT genes not only share high sequence conservation but also show specific expression in homologous plant structures that serve as propagules. Functional analysis of Arabidopsis smft mutant lines pointed to a function for this gene in regulating seed germination, both concerning primary dormancy release and in response to adverse high-temperature conditions. Overall, our study reveals an increasing complexity in the evolutionary history of the PEBP gene family, unlocking new potential in understanding the evolution and functional spectrum of these important key regulatory genes.

Pumpkin seed oil lessens the colchicine-induced altered sex male hormone balance, testicular oxidative status, sperm abnormalities, and collagen deposition in male rats via Caspase3/Desmin/PCNA modulation.

This study examined the efficiency of pumpkin seed oil (PSO) to rescue the colchicine (CHC)-induced adverse impacts on sperm characteristics, male sex hormones, testicular architecture, oxidative status, DNA content, collagen deposition, and immune expression of desmin and PCNA. Male Sprague Dawley rats were divided into four experimental groups (n = 10 each): control (distilled water), CHC (0.6 mg/kg b.wt), PSO (4 mL/kg b.wt), and CHC + PSO. After 60 days of dosing, CHC significantly reduced sperm motility (19%), sperm concentration (38%), estradiol (52%), testosterone (37%), luteinizing hormone (54%), and follicle-stimulating hormone (29%) compared to the control. Yet, the testicular tissues of CHC-administered rats exhibited elevated abnormal sperms (156%), malondialdehyde (354%), lactate dehydrogenase (73%), Caspase-3 (66%), and 8-hydroxyguanosine (65%) but lower reduced glutathione (74%), catalase (73%), and superoxide dismutase (78%) compared to the control group. Moreover, CHC induced testicular degeneration, distorted seminiferous tubules, apoptotic cells, exfoliated spermatogenic cells, reduced DNA content, decreased PCNA and desmin immune-expression, and increased collagen deposition. PSO effectively reversed the CHC-induced alterations in sperm quality and testicular function and architecture, likely through its antioxidant, antifibrotic, anti-apoptotic, and DNA-protective properties. These results suggest that PSO may be a beneficial intervention for long-term CHC users and may protect against CHC-induced male reproductive toxicity.

Change of bioactive properties, spectral reflectance, and color characteristics of European cranberry (Viburnum opulus L.) juice as affected by foam mat drying technique.

The European cranberry bush, known for its health benefits, can only be consumed through fermentation. This study aimed to develop a fruit leather made from European cranberry bush using quince seed gel and the foam drying method. For this purpose, quince seed gel was added to European cranberry juice to increase consistency. Then, European cranberry fruit leather was obtained by drying at 70, 80, and 90 °C air temperatures using foam mat drying technology. Spectral reflectance, color, drying kinetics, anthocyanin, ascorbic acid, and total phenolic content, antiradical activity, and macro-micronutrient concentrations of the resulting fruit pulp were investigated. The foam mat drying process at 90 °C had the greatest values of ascorbic acid (0.996 mg g- 1), anthocyanin (275.9 mg kg- 1), DPPH (47.77%), and ABTS.+ (68.76 µg TE g- 1). In addition, the highest value of total phenolic content (37.75 mg g- 1) was obtained in the foam mat drying process at 80 °C. The highest concentration of P, Na, Mg, K, Ca, and Mn in fruit leather was obtained at 70 °C, and the highest concentration of S, Cu, and Zn was obtained at 90 °C. The lowest spectral reflectance values were measured at 90 °C. In conclusion, the present study explored the fact that adding quince seed gel, extremely rich in biochemical content, significantly enhanced the bioactivity properties of European cranberry bush fruit leather.

Bacterial seed endophytes promote barley growth and inhibits Fusarium graminearum in vitro.

OBJECTIVES: Seeds host microbes that function in plant growth and phytopathogen resistance. The aim of the work was to investigate total bacterial community in malting barley seeds and whether their bacterial seed endophytes have dual functional roles in plant growth-promotion and inhibition of Fusarium graminearum, the causative agent of Fusarium head blight (FHB) in barley. We used culture dependent and culture independent methods. RESULTS: Phylogenetic classification of seed endophytic bacteria based on sequencing data identified B. subtilis, B. licheniformis and B. pumilis as predominant subgroups. Location driven divergence in bacterial endophytic communities was evident based on a clear separation of the samples from Crookston and other location samples. The bio-primed seeds using one hundred and seventy bacterial isolates showed that 3.5% (6/170) of the bacterial isolates conferred greater than 10% increase in both root length (RL) and shoot length (SL), while 19.4% (33/170) and 26.5% (45/170) showed RL and SL specific growth effects, respectively, relative to controls. Among the six bacterial isolates that increased RL and SL, five (#29, #63, #109, #124 and #126) also significantly inhibit the growth of F. graminearum based on in vitro assays. This study identified novel seed bacterial endophytes that could be further exploited for promoting growth during seedling establishment and as biocontrol for combating the devastating scab disease.

Optimization and pharmacological evaluation of phytochemical-rich Cuscuta reflexa seed extract for its efficacy against chlorpyrifos-induced hepatotoxicity in murine models.

The popular organophosphorus (OP) compound chlorpyrifos (CP) has recently gained significant attention due to its health risks, particularly among farmers exposed to OP pesticides. This study aimed to evaluate the acute toxicity of Cuscuta reflexa seed extract (CRSE) and its efficacy of mitigating the adverse effects of CP in albino male mice. For acute toxicity analysis, the first group was served as the control group, while the second group was received CRSE (200 mg/kg/bw) on the first day of the 14-day experiment. For hepatotoxicity analysis, the first group was the control group, the second group (vehicle control) received corn oil (CO) (2 mL/kg/bw), the third group was given CP (20 mg/kg/bw) dissolved in corn oil and the fourth group was given CP (20 mg/kg/bw) along-with CRSE (200 mg/kg/bw) orally via gavage once daily for 21 days. The acute toxicity examination revealed no statistically significant differences between the CRSE-treated and control groups in serum biochemical indicators and histopathological analyses of various organs, suggesting that CRSE as safe at a dosage of 200 mg/kg/bw, with an oral LD50 in mice higher than 200 mg/kg. The hepatotoxicity study demonstrated that the CP administration resulted in liver damage and oxidative stress, while CRSE acted as an antioxidant and attenuated the signs of oxidative stress in liver damage. Hence, a promising therapeutic approach for lowering CP hepatotoxicity is co-treatment with CRSE.

Physiological and gene expression response mechanisms of dehydration process in Cinnamomum cassia (L.) J. Presl seeds.

BACKGROUND: A critical factor in the storability of recalcitrant seeds is their moisture content (MC), but its effect on the viability of Cinnamomum cassia (L.) J. Presl (C. cassia) seeds is not fully understood. METHODS AND RESULTS: Measured the germination rate, starch and soluble sugar content, and transcriptome of 8 seed samples with different MC obtained by low-temperature drying method. It was found that the germination rate was significantly negatively correlated with MC. The lethal MC was around 15.6%. During the dehydration process, there was a significant increase in the content of soluble sugars and starch. Transcriptome analysis was performed on CK, W3, W6 showed a total of 62.78 Gb of clean data. Among the 30,228 Unigenes, 28,195 were successfully annotated. In the three comparative groups (CK and W3, CK and W6, W3 and W6), 6,842, 7,640, and 11,628 differentially expressed genes (DEGs) were obtained, respectively. These DEGs were found to be involved in a variety of metabolic pathways, including carbon metabolism, amino acid biosynthesis, starch and sucrose metabolism, glycolysis/gluconeogenesis, and nucleotide and amino sugar metabolism. A total of 1,416 common genes were identified among all three comparison groups. Furthermore, among all the DEGs, a total of 71 transcription factor families were identified, with the C2H2 transcription factor family having the highest number of genes. CONCLUSIONS: This ground-breaking study sheds light on the physiological response and gene expression profiles of C. cassia seeds after undergoing dehydration treatment, which will provide valuable insights for further research and understanding of this process.

Knockdown of ß-conglycinin α' and α subunits alters seed protein composition and improves salt tolerance in soybean.

Soybean is an important plant source of protein worldwide. Increasing demands for soybean can be met by improving the quality of its seed protein. In this study, GmCG-1, which encodes the ß-conglycinin α' subunit, was identified via combined genome-wide association study and transcriptome analysis. We subsequently knocked down GmCG-1 and its paralogues GmCG-2 and GmCG-3 with CRISPR-Cas9 technology and generated two stable multigene knockdown mutants. As a result, the ß-conglycinin content decreased, whereas the 11S/7S ratio, total protein content and sulfur-containing amino acid content significantly increased. Surprisingly, the globulin mutant exhibited salt tolerance in both the germination and seedling stages. Little is known about the relationship between seed protein composition and the salt stress response in soybean. Metabonomics and RNA-seq analysis indicated that compared with the WT, the mutant was formed through a pathway that was more similar to that of active salicylic acid biosynthesis; however, the synthesis of cytokinin exhibited greater defects, which could lead to increased expression of plant dehydrin-related salt tolerance proteins and cell membrane ion transporters. Population evolution analysis suggested that GmCG-1, GmCG-2, and GmCG-3 were selected during soybean domestication. The soybean accessions harboring GmCG-1Hap1 presented relatively high 11S/7S ratios and relatively high salt tolerance. In conclusion, knockdown of the ß-conglycinin α and α' subunits can improve the nutritional quality of soybean seeds and increase the salt tolerance of soybean plants, providing a strategy for designing soybean varieties with high nutritional value and high salt tolerance.

Dual-Seed Strategy for High-Performance Anode-Less All-Solid-State Batteries.

Interest in all-solid-state batteries (ASSBs), particularly the anode-less type, has grown alongside the expansion of the electric vehicle (EV) market, because they offer advantages in terms of their energy density and manufacturing cost. However, in most anode-less ASSBs, the anode is covered by a protective layer to ensure stable lithium (Li) deposition, thus requiring high temperatures to ensure adequate Li ion diffusion kinetics through the protective layer. This study proposes a dual-seed protective layer consisting of silver (Ag) and zinc oxide (ZnO) nanoparticles for sulfide-based anode-less ASSBs. This dual-seed-based protective layer not only facilitates Li diffusion via multiple lithiation pathways over a wide range of potentials, but also enhances the mechanical stability of the anode interface through the in situ formation of a Ag-Zn alloy with high ductility. The capacity retention during full-cell evaluation is 80.8% for 100 cycles when cycled at 1 mA cm-2 with 3 mAh cm-2 at room temperature. The dual-seed approach provides useful insights into the design of multi-seed concepts in which, from a mechanochemical perspective, various lithiophilic materials synergistically impact upon the anode-less interface.

The presence of a significant endophytic fungus in mycobiome of rice seed compartments.

Seed microbial communities have been known to have a crucial role in the life cycle of a plant. In this study, we examined the distribution of the fungal communities in three compartments (husk, brown rice, and milled rice) of the fourteen rice seed samples. Ten fungal genera distributed throughout the three compartments of the rice seeds were identified as the core mycobiome of the rice seeds, regardless of collecting regions or cultivars. Based on the diversity analysis, the distribution of the fungal community in milled rice was found to be more diversified, evenly distributed, and differently clustered from the other two compartments. Among the core mycobiome, Moesziomyces dominated almost 80% of the fungal communities in the outer compartments of rice seeds, whereas the abundances of other endophytic pathogenic fungi declined. Our results provide that antagonistic yeast Moesziomyces may be able to control the endogenous pathogenic fungal communities in rice seeds, hence maintaining the quality of rice seeds. In addition, the distribution of fungal communities differs depending on the rice seed's compartment, indicating that the compartment can affect the distribution of the seed microbial community.

Alasemenia, the earliest ovule with three wings and without cupule.

The ovules or seeds (fertilized ovules) with wings are widespread and especially important for wind dispersal. However, the earliest ovules in the Famennian of the Late Devonian are rarely known about the dispersal syndrome and usually surrounded by a cupule. From Xinhang, Anhui, China, we now report a new taxon of Famennian ovules, Alasemenia tria gen. et sp. nov. Each ovule of this taxon possesses three integumentary wings evidently extending outwards, folding inwards along abaxial side and enclosing most part of nucellus. The ovule is borne terminally on smooth dichotomous branches and lacks a cupule. Alasemenia suggests that the integuments of the earliest ovules without a cupule evolved functions in probable photosynthetic nutrition and wind dispersal. It indicates that the seed wing originated earlier than other wind dispersal mechanisms such as seed plume and pappus, and that three- or four-winged seeds were followed by seeds with less wings. Mathematical analysis shows that three-winged seeds are more adapted to wind dispersal than seeds with one, two or four wings under the same condition.

Many plants need seeds to reproduce. Seeds come in all shapes and sizes and often have extra features that help them disperse in the environment. For example, some seeds develop wings from seed coat as an outer layer, similar to fruits of sycamore trees that have two wings to help them glide in the wind. The first seeds are thought to have evolved around 372-359 million years ago in a period known as the Famennian (belonging to the Late Devonian). Fossil records indicate that almost all these seeds were surrounded by an additional protective structure known as the cupule and did not have wings. To date, only two groups of Famennian seeds have been reported to bear wings or wing-like structures, and one of these groups did not have cupules. These Famennian seeds all had four wings. Wang et al. examined fossils of seed plants collected in Anhui province, China, which date to the Famennian period. The team identified a new group of seed plants named the Alasemenia genus. The seeds of these plants each had three wings but no cupules. The seeds formed on branches that did not have any leaves, which indicates the seeds may have performed photosynthesis (the process by which plants generate energy from sunlight). Mathematical modelling suggested that these three-winged seeds were better adapted to being dispersed by the wind than other seeds with one, two or four wings. These findings suggest that during the Famennian the outer layer of some seeds that lacked cupules evolved wings to help the seeds disperse in the wind. It also indicates that seeds with four or three wings evolved first, followed by other groups of seed plants with fewer seed wings. Future studies may find more winged seeds and further our understanding of their evolutionary roles in the early history of seed plants.

Seed abortion caused by the combination of two duplicate genes in the progeny from the cross between Oryza sativa and Oryza meridionalis.

Seed development is an essential phenomenon for all sexual propagative plant species. The functional allele at SEED DEVELOPMENT 1 (SDV1) or SEED DEVELOPMENT 2 (SDV2) loci is essential for seed development for Oryza sativa and Oryza meridionalis. In the present study, we performed fine mapping of SDV1, narrowing down the area of interest to 333kb on chromosome 6. Haplotype analysis around the SDV1 locus of O. meridionalis accessions indicated that they shared the DNA polymorphism, suggesting that they have a common abortive allele at the SDV1 locus. Linkage analysis of the candidate SDV2 gene showed that it was located on chromosome 4. The candidate SDV2 was confirmed using a population in which both the SDV1 and SDV2 genes were segregating. The chromosomal region covering the SDV1 gene was predicted to contain 30 protein-coding genes in O. sativa. Five of these genes have conserved DNA sequences in the chromosomal region of the SDV2 gene on chromosome 4, and not on chromosome 6, of O. meridionalis. These results suggest that these five genes could be candidates for SDV1, and that their orthologous genes located on chromosome 4 of O. meridionalis could be candidates for SDV2.