Excavating the quantitative trait locus (QTL) associated with rice cooking quality, analyzing candidate genes, and improving cooking quality-associated traits of rice varieties by genetic breeding can effectively improve the taste of rice. In this study, we used the indica rice HZ, the japonica rice Nekken2 and 120 recombinant inbred lines (RILs) populations constructed from them as experimental materials to measure the gelatinization temperature (GT), gel consistency (GC) and amylose content (AC) of rice at the maturity stage. We combined the high-density genetic map for QTL mapping. A total of 26 QTLs associated with rice cooking quality (1 QTL associated with GT, 13 QTLs associated with GC, and 12 QTLs associated with AC) were detected, among which the highest likelihood of odd (LOD) value reached 30.24. The expression levels of candidate genes in the localization interval were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR), and it was found that the expression levels of six genes were significantly different from that in parents. It was speculated that the high expression of LOC_Os04g20270 and LOC_Os11g40100 may greatly increase the GC of rice, while the high expression of LOC_Os01g04920 and LOC_Os02g17500 and the low expression of LOC_Os03g02650 and LOC_Os05g25840 may reduce the AC. The results lay a molecular foundation for the cultivation of new high-quality rice varieties, and provide important genetic resources for revealing the molecular regulation mechanism of rice cooking quality.
Quantitative Trait Loci ; Oryza/genetics* ; Plant Breeding ; Cooking ; Genetic Association Studies

This study compared the changes in chemical components during the processing of different types of Aconiti Lateralis Radix Praeparata(ALRP) in "Jianchang" faction, i.e., dried ginger-steamed ALRP pieces(Yin-FP), sand-fried ALRP pieces(Yang-FP), and rice swill water-bleached ALRP pieces(DFP), and provided a scientific basis for the mechanism in toxicity reduction and efficacy enhancement from a compositional perspective. Samples were collected during the processing of the three types of ALRP pieces, yielding raw ALRP pieces, water-bleached Yin-FP, ginger juice-moistened Yin-FP, steamed Yin-FP, water-bleached Yang-FP, sand-fried Yang-FP, water-bleached DFP, rice swill water-bleached DFP, and roasted DFP. Aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine, benzoylhypaconine, aconine, mesaconine, hypaconine, salsolinol, fuziline, and higenamine in the extracts were determined by UPLC-MS/MS, and then content analysis and cluster heatmap analysis were performed on 11 sets of samples. During the processing of the three types of ALRP pieces, bleaching significantly reduced the content of 12 alkaloids; steaming, stir-frying, and roasting significantly reduced the content of diester-type alkaloids(aconitine, mesaconitine, and hypaconitine) and significantly increased the content of monoester-type alkaloids(benzoylaconine, benzoylmesaconine, and benzoylhypaconine) and aminoalcohol-type alkaloids(aconine, mesaconine, and hypaconine). During the processing of Yin-FP, the diester-type alkaloids continuously decreased, while the monoester-type and aminoalcohol-type alkaloids showed an initial decrease followed by an increase. During the processing of Yin-FP, Yang-FP, and DFP, the diester-type alkaloids continuously decreased, while the monoester-type and aminoalcohol-type alkaloids showed an initial decrease followed by an increase. Steamed Yin-FP showed a higher increase in content than fried Yang-FP and roasted DFP. Comprehensive analysis of content differences in toxic and therapeutic components in three ALRP pieces suggests that the distinctive processing methods in "Jianchang" faction can indeed achieve detoxification and efficacy enhancement on ALRP. This study provides references for understanding the mechanisms of action of the three processing methods.
Aconitine/analysis* ; Tandem Mass Spectrometry ; Zingiber officinale ; Oryza ; Sand ; Liquid Chromatography-Mass Spectrometry ; Chromatography, Liquid ; Drugs, Chinese Herbal/chemistry* ; Chromatography, High Pressure Liquid/methods* ; Alkaloids/analysis* ; Steam

Recently, returning straw to the fields has been proved as a direct and effective method to tackle soil nutrient loss and agricultural pollution. Meanwhile, the slow decomposition of straw may harm the growth of the next crop. This study aimed to determine the effects of rumen microorganisms (RMs) on straw decomposition, bacterial microbial community structure, soil properties, and soil enzyme activity. The results showed that RMs significantly enhanced the degradation rate of straw in the soil, reaching 39.52%, which was 41.37% higher than that of the control on the 30th day after straw return. After 30 d, straw degradation showed a significant slower trend in both the control and the experimental groups. According to the soil physicochemical parameters, the application of rumen fluid expedited soil matter transformation and nutrient buildup, and increased the urease, sucrase, and cellulase activity by 10%‒20%. The qualitative analysis of straw showed that the hydroxyl functional group structure of cellulose in straw was greatly damaged after the application of rumen fluid. The analysis of soil microbial community structure revealed that the addition of rumen fluid led to the proliferation of Actinobacteria with strong cellulose degradation ability, which was the main reason for the accelerated straw decomposition. Our study highlights that returning rice straw to the fields with rumen fluid inoculation can be used as an effective measure to enhance the biological value of recycled rice straw, proposing a viable solution to the problem of sluggish straw decomposition.
Animals ; Rumen/metabolism* ; Agriculture/methods* ; Soil/chemistry* ; Microbiota ; Bacteria/metabolism* ; Oryza/metabolism* ; Soil Microbiology ; Cellulose

The present study aimed to investigate the effect of various adjuvant rice on the quality of rice-steamed Rehmanniae Radix(RSRR) with Japonica rice, millet, yellow rice, black rice, and glutinous rice as raw materials, and analyze the anti-osteoporosis effect of RSRR by the optimal adjuvant rice. On the basis of the established UPLC-MS/MS method for the determination of the content of catalpol and rehmannioside D, comprehensive weighted scoring method was employed to evaluate the effect of various auxiliary rice on the quality of RSRR with the content of catalpol and rehmannioside D, character score, and taste score as indicators to optimize adjuvant rice. The osteoporosis model was induced by ovariectomy in rats. SD rats were randomly divided into a sham operation group, a model group, a positive control group, and low-dose and high-dose groups of Rehmanniae Radix, RSRR, steamed Rehmanniae Radix, and Epimedii Folium-RSRR. After treatment for 12 weeks, body weight, bone calcium content, and bone mineral density were mea-sured. The results showed that Japonica rice was selected as the optimal adjuvant due to the highest comprehensive score of RSRR steamed by Japonica rice. Rehmanniae Radix, RSRR, steamed Rehmanniae Radix, as well as Epimedii Folium-RSRR, could improve osteoporosis by increasing bone calcium content and bone mineral density. RSRR was superior to Rehmanniae Radix in improving osteo-porosis. However, there was no significant difference between RSRR and steamed Rehmanniae Radix. This study confirmed that Japo-nica rice was the optimal adjuvant rice of RSRR and verified the anti-osteoporosis effect of RSRR, which laid a foundation for further research on the pharmacological action and mechanism of RSRR.
Female ; Rats ; Animals ; Oryza ; Chromatography, Liquid ; Calcium ; Rats, Sprague-Dawley ; Tandem Mass Spectrometry ; Drugs, Chinese Herbal/pharmacology* ; Osteoporosis/drug therapy* ; Rehmannia ; Adjuvants, Pharmaceutic

Iron (Fe) deficiency and excess cadmium (Cd) in rice grain are important problems to be solved in agricultural production. Previous studies have shown that OsVIT1 and OsVIT2 are vacuolar iron transporters. In this study, wild-type ZH11 was selected as the background material and OsVIT1 and OsVIT2 were overexpressed in endosperm by using endosperm specific promoter Glb-1. Field experiments were conducted to study the effect of OsVIT1 and OsVIT2 overexpression on Fe and Cd accumulation in different parts of rice. The results showed that OsVIT1 overexpression in endosperm significantly reduced Fe content in grain by about 50%, while significantly increased zinc (Zn) and copper (Cu) contents in straw and Cu content in grain. OsVIT2 overexpression in endosperm significantly decreased Fe and Cd contents in grain by about 50%, and significantly increased Fe content in straw by 45%-120%. Overexpression of OsVIT1 and OsVIT2 in endosperm did not affect the agronomic traits of rice. In conclusion, OsVIT1 and OsVIT2 overexpression in endosperm reduced Fe accumulation in rice grain, which did not achieve the expected effect. OsVIT2 overexpression in endosperm also decreased Cd accumulation in grain and increased Fe accumulation in straw, which provided reference for iron biofortification and cadmium reduction in rice.
Cadmium ; Endosperm/chemistry* ; Oryza/genetics* ; Iron ; Zinc ; Edible Grain ; Soil Pollutants

In this study, a new Bacillus velezensis strain Bv-303 was identified and its biocontrol effect against rice bacterial-blight (BB) disease caused by Xanthomonas oryzae pv. oryzae (Xoo) was investigated. Cell-free supernatant (CFS) of strain Bv-303 under different growth conditions were prepared to test the antagonistic activity and stability against Xoo by the Oxford-cup method in vitro. The antibacterial effect of strain Bv-303 to BB disease in rice were further analyzed in vivo by spraying the cell-culture broth (CCB), CFS and cell-suspension water (CSW), respectively, on the rice leaves inoculated with Xoo. Additionally, rice seeds germination rate and seedling growth under the strain Bv-303 CCB treatment were tested. The results showed that the strain Bv-303 CFS significantly inhibited Xoo growth by 85.7%‒88.0% in vitro, which was also stable under extreme environment conditions such as heat, acid, alkali and ultraviolet light. As tested in vivo, spraying the CCB, CFS or CSW of strain Bv-303 on the Xoo-infected leaves enhanced rice plant resistance to BB disease, with CCB showing the highest increase (62.7%) in disease-resistance. Notably, CCB does not have negative effects on rice seed germination and seedling growth. Therefore, strain Bv-303 has great potential for biocontrol of the rice BB disease.
Oryza ; Fatigue Syndrome, Chronic ; Bacillus ; Xanthomonas ; Plant Diseases/microbiology*

Rice stripe virus (RSV) transmitted by the small brown planthopper causes severe rice yield losses in Asian countries. Although viral nuclear entry promotes viral replication in host cells, whether this phenomenon occurs in vector cells remains unknown. Therefore, in this study, we systematically evaluated the presence and roles of RSV in the nuclei of vector insect cells. We observed that the nucleocapsid protein (NP) and viral genomic RNAs were partially transported into vector cell nuclei by utilizing the importin α nuclear transport system. When blocking NP nuclear localization, cytoplasmic RSV accumulation significantly increased. In the vector cell nuclei, NP bound the transcription factor YY1 and affected its positive regulation to FAIM. Subsequently, decreased FAIM expression triggered an antiviral caspase-dependent apoptotic reaction. Our results reveal that viral nuclear entry induces completely different immune effects in vector and host cells, providing new insights into the balance between viral load and the immunity pressure in vector insects.
Animals ; Cell Nucleus ; Hemiptera/metabolism* ; Insect Vectors/genetics* ; Insecta ; Nucleocapsid Proteins/metabolism* ; Oryza ; Plant Diseases ; Tenuivirus/metabolism* ; Virus Replication

Cultivating salt-alkali tolerant rice varieties is one of the important ways to meet the increasing food demand of growing global population. In this study, twenty-one rice germplasms with different salt-alkali tolerance were treated with six salt-alkali concentrations at germination and seedling stages. The germination potential, germination rate, shoot length, root length, root number, fresh weight of shoot and seedlings were measured. The average value of salt damage rate was used to evaluate the salt-alkali tolerance. As the salt-alkali concentration increases, the inhibition on seed germination and growth became more obvious. Upon treatment with 1% NaCl plus 0.25% NaHCO₃, the salt damage rate of germination rate has the largest variation, ranging from 0% to 89.80%. The salt damage rate of each trait shows a similar trend at all concentrations. Four germplasm resources with strong salt-alkali tolerance (Dajiugu, Nippobare, Mowanggu and 02428) and 7 sensitive germplasms were screened. The salt-tolerant gene sequence of 4 salt-alkali tolerant varieties and 3 sensitive germplasms were analyzed. OSHAL3 and OsRR22 were identical among the 7 germplasms, but SKC1 and DST showed clear variations between the salt-alkali tolerant and sensitive germplasms. Besides the salt-alkali tolerant germplasm resources, this study can also serve as a reference for mining of genes involved in salt-alkali tolerance and breeding of salt-alkali tolerant rice varieties.
Alkalies ; Germination ; Oryza/genetics* ; Plant Breeding ; Seedlings/genetics*

The aim of this study was to develop a semi-quantitative immunochromatographic method for rapid detection of Newcastle disease virus (NDV) antibodies by expressing HN protein in rice endosperm bioreactor. The recombinant plasmid pUC57-HN was digested by MlyⅠ and XhoⅠ to retrieve the HN gene, while the intermediate vector pMP3 containing promoter, signal peptide and terminator was digested by NaeⅠ and XhoⅠ. The HN gene and the linearized pMP3 were purified and ligated to form a recombinant plasmid pMP3-HN1. Subsequently, pMP3-HN1 and plant vector pCAMBIA1300 were digested by EcoRⅠ and Hind Ⅲ, and the HN1 gene was cloned into pCAMBIA1300. The recombinant plasmid pCAMBIA1300-HN1 was introduced into Agrobacterium tumefaciens EHA105 by electrotransformation, and the pCAMBIA1300-HN1 was transferred into rice callus by agrobacterium-mediated method. After dark culture, callus screening, differentiation, rooting and transplanting, transgenic rice seeds were obtained 4 months later. PCR identified that the HN gene has been inserted into the rice genome. SDS-PAGE and Western blotting indicated that the HN protein was successfully expressed in the positive rice endosperm. The purity of the HN protein was more than 90% by SP cation exchange chromatography and gel filtration chromatography. According to the national standards for the diagnostic techniques of Newcastle disease HI test (HI≥4log₂, positive antibody reaction), a colloidal gold labeled purified HN protein was used to prepare a semi-quantitative test strip by double-antibody sandwich method for rapid detection of NDV antibody. The results showed that the test strip did not cross-react with positive sera against other viruses, and the sensitivity of the test strip reached 1:102 400 for standard positive sera of Newcastle disease. Testing of a total of 308 clinical sera showed that the compliance rate of the test strip with HI test was 97.08%, and the Kappa value was 0.942. In conclusion, high purity recombinant HN protein was obtained from rice endosperm, and a simple, rapid, highly sensitive and highly specific semi-quantitative immunochromatographic strip was developed. The test strip could be used for immune evaluation of the Newcastle disease vaccine.
Animals ; Antibodies, Viral ; Chickens ; HN Protein/metabolism* ; Newcastle Disease/prevention & control* ; Newcastle disease virus/metabolism* ; Oryza/genetics*

With the rice-steamed Rehmanniae Radix unearthed from the tomb of Haihunhou in the Western Han Dynasty as the re-ference, the present study evaluated the quality of Rehmanniae Radix and investigated the processing technology of rice-steamed Rehmanniae Radix to lay the foundation for the research on rice-steamed Rehmanniae Radix products. With catalpol and rehmannioside D as the investigation indexes, the quality and grade of Rehmanniae Radix from different producing areas were evaluated with the methods in 2020 edition of Chinese Pharmacopoeia. UPLC method was established for the determination of catalpol and rehmannioside D in the rice-steamed Rehmanniae Radix. The effects of steaming time, the amount of supplementary rice, and steaming times in the rice-steamed processing on the quality of products were investigated by L_9(3~4) orthogonal test and multi-index comprehensive balance scoring method combined with the content of catalpol and rehmannioside D and appearance characteristics. At last, the stability of the processing technology was tested. The results showed that the optimal processing technology for rice-steamed Rehmanniae Radix was as follows: Rehmanniae Radix and rice(200 g∶4 g) were steamed twice at atmospheric pressure, four hours each time. The mass fractions of catalpol and rehmannioside D were 0.184% and 0.335%, respectively, and the character score was 6.5. The processing conditions are reaso-nable, stable, and feasible. It can provide a basis for the restoration of the ancient rice-steamed processing technology and references for the development of rice-steamed Rehmanniae Radix products in the future.
Drugs, Chinese Herbal/pharmacology* ; Oryza ; Plant Extracts ; Rehmannia ; Technology