Sea Rice Research Articles

Marker-Assisted Selection of Jacalin-Related Lectin Genes OsJRL45 and OsJRL40 Derived from Sea Rice 86 Enhances Salt Tolerance in Rice.

Soil salinization limits rice growth and is an important restriction on grain yield. Jacalin-related lectins are involved in multiple stress responses, but their role in salt stress responses and use as molecular markers for salt tolerance remain poorly understood. Salt stress treatments and RT-qPCR analyses of Sea Rice 86 (SR86), 9311, and Nipponbare (Nip) showed that OsJRL45 and OsJRL40 enhanced tolerance of salt stress in SR86. Molecular markers based on sequence differences in SR86 and the salt-sensitive variety, 9311, in the intergenic region between OsJRL45 and OsJRL40 were validated in recombinant inbred lines derived from SR86 and 9311, hybrid populations, and common rice varieties. Yeast two-hybrid and bimolecular fluorescence complementation demonstrated that OsJRL45 and OsJRL40 interacted. Co-transformation of Nip with OsJRL45 and OsJRL40 derived from SR86 had no effect on the mature phenotype in T2 plants; however, salt stress at the three-leaf stage led to significant increases in CAT, POD, SOD, and Pro contents, but reduced MDA content in transgenic plants. Transcriptomic analysis identified 834 differentially expressed genes in transgenic plants under salt stress. GO and KEGG enrichment analyses indicated that metabolic pathways related to antioxidant responses and osmotic balance were crucial for salt-stress tolerance. Thus, molecular markers based on nucleotide differences in OsJRL45 and OsJRL40 provide a novel method for identifying salt-tolerant rice varieties.

Automatic Identification of Sea Rice Grains in Complex Field Environment Based on Deep Learning

The number of grains per sea rice panicle is an important parameter directly related to rice yield, and it is also a very important agronomic trait in research related to sea rice breeding. However, the grain number per sea rice panicle still mainly relies on manual calculation, which has the disadvantages of being time-consuming, error-prone, and labor-intensive. In this study, a novel method was developed for the automatic calculation of the grain number per rice panicle based on a deep convolutional neural network. Firstly, some sea rice panicle images were collected in complex field environment and annotated to establish the sea rice panicle image data set. Then, a sea grain detection model was developed using the Faster R-CNN embedded with a feature pyramid network (FPN) for grain identification and location. Also, ROI Align was used to replace ROI pooling to solve the problem of relatively large deviations in the prediction frame when the model detected small grains. Finally, the mAP (mean Average Precision) and accuracy of the sea grain detection model were 90.1% and 94.9%, demonstrating that the proposed method had high accuracy in identifying and locating sea grains. The sea rice grain detection model can quickly and accurately predict the number of grains per panicle, providing an effective, convenient, and low-cost tool for yield evaluation, crop breeding, and genetic research. It also has great potential in assisting phenotypic research.

Ceramides from sea red rice bran ameliorate oxidative stress and lifespan in Caenorhabditis elegans by activating the p38/MAPK signaling pathway and regulating the gut microbiota

Sea red rice bran, a new salinity-tolerant sea rice by-product, contains high levels of ceramides (Cers), which are necessary to tap into their bioactivity for improving the health effects of the organism. This study aimed to investigate the effect of Cers on the improving the oxidative stress and lifespan of C. elegans, and the relationship of the interaction through the p38/MAPK signaling pathway and under the regulation of intestinal flora. The results showed that Cers treatment effectively reversed the oxidative damage caused by paraquat and hydrogen peroxide in C. elegans and reduced overexpression of ROS and accumulation of mitochondrial membrane damage. In addition, Cers intake successfully activated all gene targets of p38/MAPK signaling pathway, significantly promoted the migration of SKN-1 to the nucleus, and increased the abundance of probiotic bacteria such as Ruminoccus, AKKermansia, and Lactobacillus in the intestinal flora and effectively mitigated the adverse effects of oxidative stress. Therefore, these results indicate that Cers could be effectively in ameliorating the level of oxidative stress in the body, thereby increasing longevity and health indicators. Providing a theoretical basis for the prevention of aging-related chronic diseases and health care, and enhancing the high-value comprehensive utilization of sea red rice by-products.

Screening of Rice (Oryza sativa L.) Genotypes for Salinity Tolerance and Dissecting Determinants of Tolerance Mechanism.

Soil salinity imposes osmotic, ionic, and oxidative stresses on plants, resulting in growth inhibition, developmental changes, metabolic adaptations, and ion sequestration or exclusion. Identifying salinity-tolerant resources and understanding physiological and molecular mechanisms of salinity tolerance could lay a foundation for the improvement of salinity tolerance in rice. In this study, a series of salinity-tolerance-related morphological and physiological traits were investigated in 46 rice genotypes, including Sea Rice 86, to reveal the main strategies of rice in responding to salinity stress at the seedling stage. No genotypes showed the same tolerance level as the two landraces Pokkali and Nona Bokra, which remain the donors for improving the salinity tolerance of rice. However, due to undesirable agronomic traits of these donors, alternative cultivars such as JC118S and R1 are recommended as novel source of salinity tolerance. Correlation and principal component analyses revealed that the salinity tolerance of rice seedlings is not only controlled by growth vigor but also regulated by ion transport pathways such as long-distance Na+ transport, root Na+ sequestration, and root K+ retention. Therefore, such key traits should be targeted in future breeding programs as the strategy of obtaining better Na+ exclusion is still the bottleneck for improving salinity tolerance in rice.

PM10 emissions from co-combustion of water washed sea rice waste with coal

Sea rice is a variety of salt-tolerant rice that absorbs significant quantities of Na, K and Cl. This work investigated effects of water washing pretreatment on sea rice waste properties, such as combustion characteristics, particulate matters (PM) emission and PM10 reduction, during its co-combustion with coal. Fuel characterizations, thermogravimetric analyses, ash fusion temperature (AFT) measurements and PM10 collection experiments were performed. A drop tube furnace was used to burn biomass and blended fuel samples at 1500 °C for PM10 collection. The results show that water washing effectively removed undesirable elements, including K, Na, and Cl. The washing pretreatment increased the AFTs of sea rice straw and ordinary rice straw, but had no effect on the husk. The washing delayed the devolatilization of sea rice waste, as did the char combustion. The yield of PM1 from the washed biomass was significantly reduced owing to the extraction of alkali metals and Cl. During co-combustion with coal, the ash particles of biomass could capture the alkali sulfides from coal, which inhibited the formation of PM1. Ca-containing particles in coal could melt and adhere to the large ash particles from the biomass to grow into larger particles, reducing the yield of PM1–10.

Complete Genome Sequence of Pseudomonas promysalinigenes Strain RL-WG26, a PGPR Isolated from the Rice Rhizosphere for Studying the Promotion of Plant Growth Under Salt Stress

The Pseudomonas promysalinigenes strain RL-WG26, which was previously isolated from the rhizosphere of Sea Rice 86 (SR86), could promote the plant growth and alleviate the plant salt stress of SR86 by regulating the ion concentration in plants, increasing the dry weight and chlorophyll content of plants, and reducing the proline and malondialdehyde content in roots. Here, we report the complete genome sequence of Pseudomonas promysalinigenes strain RL-WG26 to lay a foundation for deciphering the molecular mechanisms of strain RL-WG26-mediated plant salt tolerance and to further the application potential of this strain. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

RL-WG26 mediated salt stress tolerance in rice seedlings: A new insight into molecular mechanisms

Soil salinization has significant deleterious impacts on arable lands and crop productivity worldwide. Plant growth–promoting rhizobacteria (PGPR) have the capability to establish mutualistic associations with plants, resulting in the increase of plant growth under abiotic stress. PGPR strain RL-WG26 was previously isolated from the rhizosphere of rice Sea Rice 86 (SR86). In this study, by genome-based average nucleotide identity (ANI) calculation, RL-WG26 was re-identified as Pseudomonas promysalinigenes here instead of Pseudomonas putida. SR86 seedlings inoculated with RL-WG26 possessed significant increases in plant biomass (fresh weight and dry weight), root surface area and length, and chlorophyll content under either normal or saline conditions, when compared with those without RL-WG26 inoculation. Ion content analysis demonstrated that seedlings inoculated with RL-WG26 contained lower Na+ and Cl– accumulation but higher K+ and Ca2+ uptake under saline condition, which finally alleviated the salt ion toxic in the RL-WG26 inoculated seedlings, when compared with those without RL-WG26 inoculation. In addition, SR86 seedlings inoculated with RL-WG26 also exhibited higher antioxidant activity and higher concentration of osmoregulation factor proline than those without RL-WG26 inoculation. At last, genomic analysis of strain RL-WG26 identified several genes and gene clusters encoding 1-aminocyclopropane-1-carboxylic acid (ACC)-deaminase, the tryptophan-dependent indole-3-acetic acid (IAA) synthesis pathway, and the synthesis of betaine. Taken together, PGPR strain RL-WG26 could enhance the growth and salt stress tolerance in SR86 seedlings through various pathways, which provide a foundation for deciphering the molecular mechanisms of strain RL-WG26-mediated plant salt tolerance and promote the application of this strain.

Jacalin-related lectin 45 (OsJRL45) isolated from ‘sea rice 86’ enhances rice salt tolerance at the seedling and reproductive stages

BackgroundRice (Oryza sativa L.) is one of the most widely cultivated grain crops in the world that meets the caloric needs of more than half the world’s population. Salt stress seriously affects rice production and threatens food security. Therefore, mining salt tolerance genes in salt-tolerant germplasm and elucidating their molecular mechanisms in rice are necessary for the breeding of salt tolerant cultivars.ResultsIn this study, a salt stress-responsive jacalin-related lectin (JRL) family gene, OsJRL45, was identified in the salt-tolerant rice variety ‘sea rice 86’ (SR86). OsJRL45 showed high expression level in leaves, and the corresponding protein mainly localized to the endoplasmic reticulum. The knockout mutant and overexpression lines of OsJRL45 revealed that OsJRL45 positively regulates the salt tolerance of rice plants at all growth stages. Compared with the wild type (WT), the OsJRL45 overexpression lines showed greater salt tolerance at the reproductive stage, and significantly higher seed setting rate and 1,000-grain weight. Moreover, OsJRL45 expression significantly improved the salt-resistant ability and yield of a salt-sensitive indica cultivar, L6-23. Furthermore, OsJRL45 enhanced the antioxidant capacity of rice plants and facilitated the maintenance of Na+-K+ homeostasis under salt stress conditions. Five proteins associated with OsJRL45 were screened by transcriptome and interaction network analysis, of which one, the transmembrane transporter Os10g0210500 affects the salt tolerance of rice by regulating ion transport-, salt stress-, and hormone-responsive proteins.ConclusionsThe OsJRL45 gene isolated from SR86 positively regulated the salt tolerance of rice plants at all growth stages, and significantly increased the yield of salt-sensitive rice cultivar under NaCl treatment. OsJRL45 increased the activity of antioxidant enzyme of rice and regulated Na+/K+ dynamic equilibrium under salinity conditions. Our data suggest that OsJRL45 may improve the salt tolerance of rice by mediating the expression of ion transport-, salt stress response-, and hormone response-related genes.

Improved sea rice yield and accelerated di-2-ethylhexyl phthalate (DEHP) degradation by straw carbonization returning in coastal saline soils

Di-2-ethylhexyl phthalate, a persistent organic contaminant, is widely distributed in the environment and poses substantial threats to human health; however, there have been few investigations regarding the risks and remediation of DEHP in coastal saline soils. In this work, we studied the influences of straw carbonization returning on sea rice yield and DEHP degradation. Straw carbonization returning significantly increased soil nutrients and reduced salt stress to improve sea rice yield. DEHP degradation efficiency was enhanced to a maximum of 78.27% in straw carbonized return with 60% sea rice, mainly attributed to the high pH value, high soil organic matter and enriched potential DEHP degraders of Nocardioides, Mycobacterium and Bradyrhizobium. Some key genes related to metabolism (esterase and cytochrome P450) and DEHP-degradation (pht4, pht5, pcaG, dmpB, catA and fadA) were elevated and explained the accelerated DEHP degradation, shifting from the benzoic acid pathway to the protocatechuate pathway in straw carbonization returning. The results obtained in this study provide a deep and comprehensive understanding of sea rice yield improvement and DEHP degradation mechanisms in coastal paddy soil by a straw carbonization returning strategy.

“Sea rice”: From traditional culinary customs to sustainable crop for high-end gastronomy?

Seaweed cuisine is booming in Western countries, but the nutritional and culinary potential of seagrasses remains largely unexplored. Seagrasses, unlike seaweeds, produce seeds. In the case of Zostera marina its seeds (commonly known as “sea rice”) have historically been used an as staple food by indigenous cultures, such as Seri Indians. Very recently, great expectations have been raised, with worldwide media coverage, about the use of the seeds as a new ingredient in some avant-garde restaurant. This article provides basic information on the biology of Z. marina, especially with regard to reproduction by seeds (the valuable gastronomic ingredient). It is important to know what are the main bottlenecks for seed production and meadow growth if seeds are to be used as novel and sustainable ingredients. One way to achieve enough seed production for gastronomic purposes may be throughout the “domestication” (farming) in natural earthen ponds near coastal areas where meadows are currently very scarce, such as in the Bay of Cadiz. This domestication not only opens up gastronomic possibilities, but part of the seed production can be used to meadow restoration, boosting the local economy, sustainability and blue carbon removal, and making the binomial gastronomy-sustainability a reality.

Impact of Sea Rice Planting on Enzymatic Activity and Microbial Community of Coastal Soils: Focus on Proteinase

Soil proteinase and proteinase-producing microbial community are closely associated with soil fertility and soil health. Sea rice has been planted in the coastal beach of Jiaozhou Bay, China, in an effort to transform saline-alkali soil into arable land. However, the knowledge regarding the bacterial degradation of organic nitrogen in sea rice soils is limited. This study aims to investigate the physicochemical characteristics and enzymatic activities of the sea rice soils, as well as the microbial communities by both the Illumina sequencing-based culture-independent technology and culture-dependent methods. Sea rice soils exhibited a lower salinity and higher organic matter content and proteinase activity, as well as an increase in both the richness and diversity of the proteinase-producing bacterial community, compared to the adjacent non-rice soils. The Proteobacteria phylum and the Gammaproteobacteria class were dominant in sea rice soils, showing higher abundance than in the reference soils. The Planococcus genus and Bacillus-like bacterial communities were abundant in the cultivable proteinase-producing bacteria isolated from sea rice soils. Furthermore, a significant proportion of the extracellular proteinase produced by the isolated soil bacteria consisted of serine proteinases and metalloproteinases. These findings provided new insights into the degradation of soil organic nitrogen in coastal agricultural regions.

Synthesis of graphene quantum dots with temperature-sensitive properties from sea rice for rapid and highly selective detection of 4-nitrophenol

Synthesis of graphene quantum dots with temperature-sensitive properties from sea rice for rapid and highly selective detection of 4-nitrophenol

The legacies of the "Father of Hybrid Rice" and the seven representative achievements of Chinese rice research: A pioneering perspective towards sustainable development.

The "Father of Hybrid Rice", Yuan Longping, created high-yield hybrid rice that can feed tens of millions of people annually. The research achievements of Yuan and his team on low cadmium-accumulating rice and sea rice, in addition to hybrid rice, as well as those of a large number of Chinese scientists engaged in rice research in other six areas, including the rice genome, purple endosperm rice, de novo domestication of tetraploid rice, perennial rice, rice blast disease, and key genes for high nitrogen use efficiency, play an important role in promoting the realization of the United Nations Sustainable Development Goals 2 and 12. The purpose of this review is not to elaborate on the details of each research, but to innovatively summarize the significance and inspiration of these achievements to ensure global food security and achieve sustainable agriculture. In the future, cultivating new rice varieties through modern biotechnology, such as genome editing, will not only reduce hunger, but potentially reduce human-land conflicts, improve the environment, and mitigate climate change.

Identification of Salt Tolerance Related Candidate Genes in ‘Sea Rice 86’ at the Seedling and Reproductive Stages Using QTL-Seq and BSA-Seq

Salt stress seriously affects plant growth and development and reduces the yield of rice. Therefore, the development of salt-tolerant high-yielding rice cultivars through quantitative trait locus (QTL) identification and bulked segregant analysis (BSA) is the main focus of molecular breeding projects. In this study, sea rice (SR86) showed greater salt tolerance than conventional rice. Under salt stress, the cell membrane and chlorophyll were more stable and the antioxidant enzyme activity was higher in SR86 than in conventional rice. Thirty extremely salt-tolerant plants and thirty extremely salt-sensitive plants were selected from the F2 progenies of SR86 × Nipponbare (Nip) and SR86 × 9311 crosses during the whole vegetative and reproductive growth period and mixed bulks were generated. Eleven salt tolerance related candidate genes were located using QTL-seq together with BSA. Real time quantitative PCR (RT-qPCR) analysis showed that LOC_Os04g03320.1 and BGIOSGA019540 were expressed at higher levels in the SR86 plants than in Nip and 9311 plants, suggesting that these genes are critical for the salt tolerance of SR86. The QTLs identified using this method could be effectively utilized in future salt tolerance breeding programs, providing important theoretical significance and application value for rice salt tolerance breeding.

水氮调控对根层土壤 Na+及耐盐水稻产量的影响

The cultivation of salt-tolerant rice (sea rice) along beaches has become an effective measure for the restoration and utilization of saline-sodic land, so this paper studies the effects of irrigation and nitrogen fertilization on soil Na+ in root zone and sea rice yield, and provides a scientific basis for planting sea rice. A pot experiment (two-factor split plot) of sea rice with salt stress (10 g NaCl/kg soil) was carried out. The main plot consists of three types of irrigation methods: flooding irrigation (F), intermittent irrigation (I), and controlled irrigation (C). The subplots are three types of nitrogen fertilizers: urea (U), controlled-release urea (R), and mixed fertilizer (M) with U and R. The results showed: (1) The soil water-soluble Na+ of MI was significantly smaller than that of other treatments with NaCl, but the Ca2+/Na+ and Mg2+/Na+ were opposite. (2) The nitrogen uptake and dry weight of rice of MI were significantly larger than those of other treatments with NaCl, and were respectively 23% and 32% higher than UI, 49% and 16% higher than MF, 56% and 38% higher than UF, 75% and 61% higher than RI, 76% and 50% higher than RF. (3) The sea rice yield of MI was increased by 105%, 154%, 262%, 338%, and 428% compared with MF, RF, UF, RI, and UI, respectively. Therefore, the MI can effectively reduce the Na+ and increase the Ca2+/Na+ and Mg2+/Na+ in root layer soil, and promote the nitrogen absorption and production of sea rice. So the article recommends that M and I methods should be adapted to plant sea rice on coastal saline-sodic soil.

Ceramides from Sea Red Rice Bran Improve Health Indicators and Increase Stress Resistance of Caenorhabditis elegans through Insulin/IGF-1 Signaling (IIS) Pathway and JNK-1.

The antiaging effects of sea red rice bran in vivo, a new saline-tolerant sea rice byproduct containing high levels of ceramides (Cers), remain unknown. This study aimed to explore the antiaging effects exerted by Cers from sea red rice bran on Caenorhabditis elegans, assess its health indicators as well as tolerance, and then reveal the mechanism of action of Cers in prolonging the mean life span through genetic studies. The results indicated that the mean life span of Cers-treated C. elegans were dose-dependent in the range of 0.10-0.50 mg/mL. Additionally, Cers improved nematode motility, reduced lipofuscin accumulation, and enhanced resistance to heat stress and antioxidant enzyme activity. Genetic studies showed that Cers treatment had altered nematode gene expression. In addition, insulin/IGF-1 and jnk-1/mitogen-activated protein kinase (MAPK) signaling pathways successfully demonstrated the longevity effects of Cers intake. In short, these results suggest that Cers enhance the resistance of C. elegans and prolong its life span.

The Accumulation Characteristics of Different Heavy Metals in Sea Rice

Here heavy metal (Cd, Zn, and Cu) accumulation features of sea rice (a salt-tolerant rice cultivar) were explored to provide a reference for preventing and controlling of heavy metals, screen new plant remediation resources, and offer the basis for safe sea rice production. The sea rice variety Hai Hong 12 (HH12) was used as the research object in the soil culture experiments conducted to investigate the effects of the addition of Cd (0, 1, 2, 4, 8 mg/kg), Zn (0, 100, 200, 300, 400 mg/kg), and Cu (0, 100, 200, 300, 400 mg/kg) on the growth and accumulation of heavy metals in different HH12 parts. At different Cd and Zn concentrations, the root biomass of HH12 decreased significantly and the shoot biomass showed no marked difference; however, Cu stress inhibited the rice biomass. The Cd content in different parts of sea rice increased with an increase in Cd levels. At 8 mg/kg, shoot and spike had the highest Cd content, which was 89.02 and 45.37 mg/kg, respectively. At 1 mg/kg Cd concentration, the Cd transport coefficient of sea rice was the highest (1.36). The Zn content was the highest in sea rice at 400 mg/kg Zn. Zn concentrations in the shoot and spike were 440.95 and 175.51 mg/kg. However, the Zn transport coefficients of all parts were <1 at different Zn concentrations. Sea rice growth was severely hampered by high Cu stress (400 mg/kg). After 200 mg/kg Cu treatment, the highest Cu content was 82.85 mg/kg in shoot and 46.97 mg/kg in spike. The Cu transport coefficients of all parts were also <1 under Cu stress and decreased with an increase in the Cu concentration. In summary, HH12 exhibited a high risk of Cd accumulation, and Cd was more likely to be transported to the grains. Zn accumulation in sea rice had no obvious toxicity to its shoot growth, but its shoot had a slight risk of Zn accumulation. Cu was mostly built up in the HH12 roots, but its ability to move around was low. However, high Cu concentrations slowed the growth of sea rice.

Effects of irrigation and nitrogen fertilization on mitigating salt-induced Na+ toxicity and sustaining sea rice growth.

This study investigated the effects of irrigation and nitrogen (N) fertilization on mitigating salt-induced Na+ toxicity and sustaining sea rice growth for perfecting irrigation and fertilization of sea rice. Three irrigation methods (submerged irrigation, intermittent irrigation, and controlled irrigation), three kinds of N fertilizers (urea, controlled release urea, and mixed N fertilizer), and control treatment without NaCl were set up in a pot experiment of sea rice with NaCl stress. The electrical conductivity in root layer soil of treatment with mixed N fertilizer and intermittent irrigation decreased slowly with the growth of rice and was significantly smaller than that of other treatments with NaCl. The Na+ content in sea rice of intermittent irrigation was the least, and that of submerged irrigation was significantly smaller than that of controlled irrigation, but the K+ and Ca2+ contents of three irrigation treatments were opposite to the Na+ content. The Na+ content of treatment with mixed N fertilizer and intermittent irrigation was the lowest, while the K+, Ca2+, and Mg2+ contents of mixed N fertilizer and intermittent irrigation were the highest in treatments with NaCl. The cell membrane permeability and malondialdehyde contents of rice leaves of mixed N fertilizer and intermittent irrigation were significantly smaller than those of other treatments with NaCl. The rice yield of mixed N fertilizer was significantly greater than that of urea and controlled release urea, and that of mixed N fertilizer and intermittent irrigation was increased by 104, 108, 277, 300, and 334% compared with mixed N fertilizer and submerged irrigation, urea and intermittent irrigation, urea and submerged irrigation, controlled release urea and intermittent irrigation, and controlled release urea and submerged irrigation, respectively. Therefore, the treatment of mixed N fertilizer and intermittent irrigation is worth recommending for being used for planting sea rice on coastal saline-sodic soil.

Effects of small-scale storage on the cooking property and fatty acid profile of sea rice paddy

This research investigated the storability of sea rice paddy in an experimental silo for 11.5 months. Water was circulated in the silo walls from June 30 to maintain a grain bulk temperature of 23°C. The dry-bulb temperatures in three layers (top, middle, and bottom) of paddy bulk showed very small differences, but the intergranular air parameters such as relative humidity (RH), wet-bulb temperature and humidity ratio in middle and bottom bulk layers were significantly higher than those of top bulk layer, and storage insects occurred in these two bulk layers from August to September as a result that sulfuryl fluoride gas fumigation was done on September 30. During storage, the rice's water absorption rate and gruel solids loss decreased with storage time, while the peak temperature of gelatinization (Tp) increased, and water uptake ratio and taste panel score remained unchanged. Fatty acid profile analysis shows that the total, saturated, and unsaturated fatty acid concentrations decreased with storage time, while the unsaturated-to-saturated fatty acid ratio increased. Compared to top bulk layer, the bottom layer had lower water absorption rate and fatty acid concentration, and a similar Tp and better cooking property. Further compared with a short-grain Japonica paddy (cv. Yanfeng) stored in a large cooled warehouse before and after oversummering, sea rice paddy stored in the experimental silo had lower protein content, but had a higher Tp, poly-unsaturated fatty acid content and unsaturated-to-saturated fatty acid ratio, and similar amylose content and taste panel score. These results suggest that sea rice has good storability, and quasi-low-temperature storage (23°C) requires autumn chemical fumigation to control the storage insects.

Microbiome-metabolome analysis directed isolation of rhizobacteria capable of enhancing salt tolerance of Sea Rice 86

Soil salinization has been recognized as one of the main factors causing the decrease of cultivated land area and global plant productivity. Application of salt tolerant plants and improvement of plant salt tolerance are recognized as the major routes for saline soil restoration and utilization. Sea rice 86 (SR86) is known as a rice cultivar capable of growing in saline soil. Genome sequencing and transcriptome analysis of SR86 have been conducted to explore its salt tolerance mechanisms while the contribution of rhizobacteria is underexplored. In the present study, we examined the rhizosphere bacterial diversity and soil metabolome of SR86 seedlings under different salinity to understand their contribution to plant salt tolerance. We found that salt stress could significantly change rhizobacterial diversity and rhizosphere metabolites. Keystone taxa were identified via co-occurrence analysis and the correlation analysis between keystone taxa and rhizosphere metabolites indicated lipids and their derivatives might play an important role in plant salt tolerance. Further, four plant growth promoting rhizobacteria (PGPR), capable of promoting the salt tolerance of SR86, were isolated and characterized. These findings might provide novel insights into the mechanisms of plant salt tolerance mediated by plant-microbe interaction, and promote the isolation and application of PGPR in the restoration and utilization of saline soil.