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1.
Huan Jing Ke Xue ; 42(7): 3451-3457, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212672

RESUMO

Hydrochar can mitigate ammonia volatilization when applied in paddy fields due to its acidity and adsorption property. To realize the recycling of agricultural biowaste as well as the control of nutrient loss from paddy fields, a simulation soil-column experiment with wheat straw hydrochar (WHC) and water-washed hydrochar (W-WHC) was conducted to evaluate the performance of rice yield and ammonia volatilization from paddy fields. The results showed that WHC and W-WHC applied in paddy fields both increased the rice yield and the increased effect at low application rate (0.5%) was higher than that at high application rate (1.5%). In comparison with the control treatment (CKU), the rice yields achieved from low application rate treatments for WHC and W-WHC increased by 17.16% and 20.20% respectively. Except for the equal emission rate between W-WHC with low application rate and CKU treatments, hydrochar (WHC, W-WHC) addition reduced the ammonia volatilization from paddy fields when compared with the CKU. Among them, the ammonia volatilization levels from low-application WHC and high-application W-WHC treatments were significantly lower than that from the CKU treatment, reduced by 31.01% and 17.40%, respectively. Based on the analysis of ammonia volatilization during different fertilization stages, the control effect of hydrochar addition on ammonia volatilization was mainly benefited from tillering and panicle fertilizer stages. The change in the nitrogen concentration of surface water at the tillering fertilizer stage and in pH at the panicle fertilizer stage with the addition of hydrochar was the main driving factor for the reduction in ammonia volatilization. The results show that sufficient amounts of hydrochar derived from wheat straw application can increase crop yield while reducing ammonia volatilization from paddy fields. This method provides an effective route for recycling agricultural biowastes.


Assuntos
Amônia , Oryza , Amônia/análise , Fertilizantes/análise , Nitrogênio/análise , Solo , Triticum , Volatilização
2.
Huan Jing Ke Xue ; 42(7): 3458-3471, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212673

RESUMO

Paddy soils are widely considered a main source of methane (CH4) and nitrous oxide (N2O). Comprehensively evaluating CH4 and N2O emissions from double-rice systems in tropical regions with different water irrigation and fertilizer applications is of great significance for addressing greenhouse gas emissions from such systems in China. In this study, eight treatments were evaluated:conventional irrigation-PK fertilizer (D-PK), conventional irrigation-NPK fertilizer (D-NPK), conventional irrigation-NPK+organic fertilizer (D-NPK+M), conventional irrigation-organic fertilizer (D-M), continuous flooding-PK fertilizer (F-PK), continuous flooding-NPK fertilizer (F-NPK), continuous flooding-NPK+organic fertilizer (F-NPK+M), and continuous flooding-organic fertilizer (F-M). CH4 and N2O emissions in double-rice fields in tropical region of china were monitored in situ by closed static chamber-chromatography method and crop yields as well as global warming potential (GWP) and greenhouse gas intensity (GHGI) were determined. The results show that:① The cumulative CH4 emissions from early rice and late rice are 10.3-78.9 kg·hm-2and 84.6-185.5 kg·hm-2, respectively. Compared with F-PK and F-NPK treatments, F-NPK+M and F-M treatments significantly increased the cumulative emissions of CH4 from early rice season. Under the same fertilizer conditions, the cumulative CH4 emissions under continuous flooding condition were significantly higher than that under conventional irrigation condition. Irrigation and fertilization had extremely significant effects on CH4 emission in the early rice season. ② The cumulative N2O emissions across all treatments were 0.18-0.76 kg·hm-2 in early rice season and 0.15-0.58 kg·hm-2in late rice season, respectively. During early rice season, compared with F-PK, F-NPK significantly increased the cumulative N2O emission; however, compared with D-PK, D-NPK, D-NPK+M, and D-M treatments significantly increased the cumulative N2O emissions. Compared with F-PK, other three treatments under continuous flooding condition significantly increased N2O cumulative emission in late rice season; compared with D-PK, D-NPK, and D-M treatment significantly increased the cumulative N2O emission. Irrigation and fertilization had significant impacts on N2O emissions in late rice season, and fertilization had significant impacts on N2O emission in early rice season. ③ Early and late rice yields were 7310.7-9402.4 kg·hm-2 and 3902.8-7354.6 kg·hm-2, respectively. Early rice yields in both F-NPK and F-M treatments were significantly higher than those in F-PK, D-PK, and D-NPK treatments. Compared with PK, the other three fertilization treatments under the same irrigation condition significantly increased late rice yield. The GWP and GHGI in early rice season were 580.8-2818.5 kg·hm-2and 0.08-0.30 kg·kg-1, respectively. There was no significant difference in GWP among four fertilizer treatments under conventional irrigation condition in the early rice season. However, F-NPK+M and F-M treatments had a significant increase in GWP compared with F-PK. The GHGI in F-NPK+M and F-M treatments were significantly higher than that in other treatments. The GWP and GHGI in late rice season were 3091.6-6334.2 kg·hm-2 and 0.50-1.23 kg·kg-1, respectively. Irrigation significantly affected GWP and GHGI in both early and late rice seasons but fertilization had no significant impact on GWP and GHGI in late rice season. ④ Correlation analysis results showed that soil NH4+-N content and soil temperature below 5 cm soil layer had an extremely significant negative correlation with CH4 emissions. Soil pH was extremely significant positive correlated with CH4 emissions but significantly negatively correlated with N2O emission. Soil NH4+-N and NO3--N concentrations were extremely significantly negatively correlated with N2O emission. Given crop yield, GWP, GHGI, and D-NPK+M can be recommended for local water and fertilizer management to reduce greenhouse gas emissions while maintaining rice yields.


Assuntos
Oryza , Agricultura , China , Fertilização , Fertilizantes/análise , Metano/análise , Óxido Nitroso/análise , Solo , Água
3.
Huan Jing Ke Xue ; 42(7): 3472-3481, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212674

RESUMO

It is known that methanogens play a critical role in the carbon cycle in soil, while methanogen community characteristics and their environmental influencing factors in the soil planted with salt-tolerant rice remain unclear. In this study, methanogen abundance, community composition, and relationships with environmental factors in soils planted with the salt-tolerant rice (YC1703) and ordinary rice (Lindao 10) were evaluated in the rice improvement demonstration base of Qingdao Wisdom Agricultural Industry using real-time fluorescence quantitative PCR and Illumina high-throughput sequencing. The results indicated that the abundance and community richness of methanogens in Lindao 10 soil were significantly higher than those in YC1703 soil, and methanogens in YC1703 soil exhibited higher diversity. The combined effects of rice varieties, rice growth period, and environmental factors had impacts on the methanogen community. The hydrogenotrophic methanogens were dominant in the YC1703 and Lindao 10 soils; thus, we speculated that the dominant pathway of methane production in these soils was hydrogenotrophic methanogenesis.


Assuntos
Euryarchaeota , Oryza , Metano , RNA Ribossômico 16S , Solo , Microbiologia do Solo
4.
Huan Jing Ke Xue ; 42(7): 3527-3534, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212679

RESUMO

Simultaneously reducing the availability of Cd and As is difficult owing to converse chemical behaviors of Cd and As in soil. In this study, amendments that can simultaneously immobilize Cd and As in soil were determined by an pure soil culture experiment in which flooding and wetting were performed for 30 d each. The effects of sepiolite (Sep), modified sepiolite (IMS and Sep-FM), steel slag (SS), and iron modified biochar (Fe-Bio) on soil pH, Eh, Cd, and As concentrations in pore water, and Cd and As fractions in soil were investigated. It showed that Sep (1%, 2.5%), IMS (1%, 2.5%), Sep-FM (1%, 2.5%), and SS (1%, 5%) treatments increased soil pH value and decreased Eh value and Cd concentrations in soil solution. In addition, As concentrations in soil solution treated with high doses of IMS (2.5%) and SS (5%) were lower than that of CK treatment during the whole incubation period. However, Fe-bio treatment decreased soil pH and increased Eh value and only decreased Cd and As concentrations in soil solution under wet conditions. Compared with the control, the application of the above amendments promoted the transformation of Cd fraction from exchangeable to reducible, oxidizable, and residual. High application rates of IMS (2.5%), Sep-FM (2.5%), and SS (5%) also reduced available As fraction (non-specifically sorbed and specifically-sorbed As fraction), and increased amorphous and poorly-crystalline hydrated Fe and Al oxide-bound As. On the contrary, Fe-bio treatment increased the fractions of non-specifically sorbed, specifically sorbed and residual As in soil. In short, IMS, Sep-FM, and SS are potential materials for remediation of Cd and As contaminated soil. They can effectively immobilize soil Cd and As and promote their transformation to the fractions that plants are difficult to uptake.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Carvão Vegetal , Poluição Ambiental/análise , Solo , Poluentes do Solo/análise
5.
Huan Jing Ke Xue ; 42(7): 3535-3548, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212680

RESUMO

Two iron-based materials, Fe-Ca composite (FeCa) and Fe-Mn binary oxide (FMBO), were applied to immobilize As, Pb, and Cd in heavy metal contaminated paddy soils. Seven kinds of paddy soil (tidal soil) contaminated by arsenic, lead and cadmium were collected from Shangyu, Shaoxing (SY), Foshan, Guangdong (FS), Shaoguan, Guangdong (SG), LiuYang, Hunan (LY), Ganzhou, Jiangxi (GZ), Dushan, Guizhou (DS), and Ma'anshan, Anhui (MAS). The effects of iron-based materials on the dynamic changes of As, Pb, and Cd concentration in soil solution, the stabilization efficacy of available As, Pb, and Cd in soil, and the effects of soil types and properties on stabilization efficacy were studied through soil incubation experiment. The results showed that the content of soil dissolved As, Pb, and Cd were lower in iron-based material treatments than in control throughout the incubation. The addition of two iron-based materials significantly reduced the availability of Cd, Pb, and As. Moreover, the stabilization efficiency of FeCa for As was higher than FMBO, but no significant difference was found in the stabilization efficiency of Pb and Cd between two materials. The stabilization efficiency of As, Pb, and Cd in FeCa treatments could be ordered as GZ > SG > DS and MAS; FS>SY, LY, and SG>MAS; SY, GZ, and DS>MAS, respectively. While the stabilization efficiency for As, Pb, and Cd in FMBO could be ordered as SY, LY, and GZ > DS > FS; FS > GZ > SY; DS > LY > MAS, respectively. In addition, the statistical results showed that the stabilization efficiencies of various soils under the treatment of iron-based materials were significantly correlated with sand content (negatively correlated for As), soil pH (positively correlated for Pb), and clay content (negatively correlated for Cd). In conclusion, the two iron-based materials evaluated in this study may be effective stabilization agents for remediating different types of arsenic-, lead-, and cadmium-contaminated soils.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Cádmio/análise , Ferro , Chumbo , Solo , Poluentes do Solo/análise
6.
Molecules ; 26(12)2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-34204643

RESUMO

Plant-derived protein hydrolysates have potential applications in nutrition. Rice protein hydrolysates (RPHs), an excellent source of proteins, have attracted attention for the development of cosmeceuticals. However, few studies have reported the potential application of RPH in analysis, and this study examined their antioxidant activities and the inhibitory activities of skin aging enzymes. The results indicated that the total phenolic and flavonoid concentrations were 2.06 ± 0.13 mg gallic acid equivalent/g RPHs and 25.96 ± 0.52 µg quercetin equivalent/g RPHs, respectively. RPHs demonstrated dose-dependent activity for scavenging free radicals from 1,1-diphenyl-2-picrylhydrazyl [half-maximal inhibitory concentration (IC50) = 42.58 ± 2.1 mg/g RPHs] and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (IC50 = 2.11 ± 0.88 mg/g RPHs), dose-dependent reduction capacity (6.95 ± 1.40 mg vitamin C equivalent/g RPHs) and oxygen radical absorbance capacity (473 µmol Trolox equivalent/g RPHs). The concentrations of the RPH solution required to achieve 50% inhibition of hyaluronidase and tyrosinase activities were determined to be 8.91 and 107.6 mg/mL, respectively. This study demonstrated that RPHs have antioxidant, antihyaluronidase, and antityrosinase activities for future cosmetic applications.


Assuntos
Hidrolisados de Proteína/química , Hidrolisados de Proteína/farmacologia , Envelhecimento/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Clareadores/química , Clareadores/metabolismo , Flavonoides/farmacologia , Sequestradores de Radicais Livres/química , Ácido Gálico/farmacologia , Camundongos , Oryza/química , Oryza/enzimologia , Oryza/metabolismo , Oxirredução , Fenóis/farmacologia , Picratos/química , Picratos/farmacologia , Extratos Vegetais/química , Quercetina/farmacologia , Células RAW 264.7 , Ácidos Sulfônicos/química , Ácidos Sulfônicos/farmacologia , Tiazóis/química , Tiazóis/farmacologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-34205130

RESUMO

The substitution of chemical pesticides by biopesticides is crucial to ensure the quality of agricultural products and to foster environmental sustainability. This study takes the willingness and the behaviors of rice farmers on the application of biopesticides as the research object. The survey questionnaire was designed based on the theory of rational small-scale farmers from three aspects: "individual and family characteristics of farmers", "cognition of farmers" and "external factors". The survey was then conducted on 163 rice farmers in seven prefecture-level cities in Jilin Province of China. The logistic model was used to analyze the influencing factors resulting in the deviation of the behaviors of the rice farmers from their initial willingness on the application of biopesticides. The explanatory structure model (ISM) was used to analyze the logical hierarchical relationship among various influencing factors. The results show that: (1) For 45% of the farmers surveyed, there's a deviation between their willingness and behaviors regarding the application of biopesticides; (2) Among the significant factors leading to the deviation between farmers' willingness and behaviors concerning the application of biopesticides, the surface-level direct factor is biopesticide awareness. The mid-level indirect factors are agricultural product quality and safety awareness and the deep-level root cause is farmers' education level. (3) The primary reason for the deviation of the farmers' behaviors from their willingness is their lack of knowledge about biopesticides and the biopesticides' incomplete market structure. Based on the comprehensive analysis, it is recommended to improve the professionalization of the farmers, to strengthen the publicity of green production and to accelerate the formulation of the biopesticides market to further promote the usage of biopesticides.


Assuntos
Fazendeiros , Oryza , Agricultura , Agentes de Controle Biológico , China , Cidades , Humanos
8.
Int J Mol Sci ; 22(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34206144

RESUMO

The Casparian strip domain protein 1 (OsCASP1) is necessary for the formation of the Casparian strip (CS) in the rice endodermis. It also controls Ca2+ transport to the stele. Here, we demonstrated that OsCASP1 overexpression enhanced Ca tolerance in rice. Under normal conditions, OsCASP1-overexpressed lines showed similar concentrations of essential metals in the roots and shoots compared to the wild type, while under high Ca conditions, Ca in the roots, shoots, and xylem sap of the OsCASP1-overexpressed lines was significantly decreased. This did not apply to other essential metals. Ca-inhibited growth was significantly alleviated in the OsCASP1-overexpressed lines. Furthermore, OsCASP1 overexpression resulted in earlier formation of both the CS and functional apoplastic barrier in the endodermis but did not induce ectopic CS formation in non-endodermal cell layers and affect suberin accumulation in the endodermis. These results indicate that the overexpression of OsCASP1 promotes CS formation in endodermal cells and inhibits Ca2+ transport by the apoplastic pathway, restricting Ca accumulation in the roots and shoots under high Ca conditions. Taken together, the results suggest that OsCASP1 overexpression is an effective way to improve rice adaptation to high Ca environments.


Assuntos
Cálcio/metabolismo , Caspase 1/genética , Oryza/genética , Caspase 1/metabolismo , Parede Celular/genética , Regulação da Expressão Gênica de Plantas/genética , Oryza/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento
9.
BMC Plant Biol ; 21(1): 326, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34229625

RESUMO

BACKGROUND: Glycolate oxidase (GLO) is not only a key enzyme in photorespiration but also a major engine for H2O2 production in plants. Catalase (CAT)-dependent H2O2 decomposition has been previously reported to be involved in the regulation of IAA biosynthesis. However, it is still not known which mechanism contributed to the H2O2 production in IAA regulation. RESULTS: In this study, we found that in glo mutants of rice, as H2O2 levels decreased IAA contents significantly increased, whereas high CO2 abolished the difference in H2O2 and IAA contents between glo mutants and WT. Further analyses showed that tryptophan (Trp, the precursor for IAA biosynthesis in the Trp-dependent biosynthetic pathway) also accumulated due to increased tryptophan synthetase ß (TSB) activity. Moreover, expression of the genes involved in Trp-dependent IAA biosynthesis and IBA to IAA conversion were correspondingly up-regulated, further implicating that both pathways contribute to IAA biosynthesis as mediated by the GLO-dependent production of H2O2. CONCLUSION: We investigated the function of GLO in IAA signaling in different levels from transcription, enzyme activities to metabolic levels. The results suggest that GLO-dependent H2O2 signaling, essentially via photorespiration, confers regulation over IAA biosynthesis in rice plants.


Assuntos
Oxirredutases do Álcool/metabolismo , Peróxido de Hidrogênio/metabolismo , Ácidos Indolacéticos/metabolismo , Oryza/enzimologia , Oxirredutases do Álcool/genética , Vias Biossintéticas/efeitos da radiação , Respiração Celular/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Luz , Modelos Biológicos , Mutação/genética , Oryza/genética , Oryza/efeitos da radiação , Peroxissomos/metabolismo , Peroxissomos/efeitos da radiação , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Triptofano/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-34232119

RESUMO

A novel Gram-stain-negative, aerobic, asporogenous, catalase-positive and oxidase-negative, non-motile, golden-yellow pigmented, rod-shaped bacterium with casein-degrading ability, designated strain GCR10T, was isolated from roots of rice plants collected from a paddy field near Dongguk University, Republic of Korea. The results of subsequent 16S rRNA gene sequence analysis indicated that GCR10T shares the highest sequence identity with Chryseobacterium piscicola VQ-6316sT (98.3%). Strain GCR10T grew at 2-32 °C (optimum, 25 °C), at pH 6.0-8.0 (optimum, pH 7.0) and in the presence of 0-2.0% (w/v) NaCl (optimum in the absence of NaCl). The novel strain was able to produce carotenoid and flexirubin-type pigments. The predominant menaquinone was MK-6 and the major fatty acids were identified as iso-C15 : 0, iso-C17 : 0 3-OH and iso-C17 : 1ω9c. The polar lipids were phosphatidylethanolamine, four unidentified aminoglycolipids, two unidentified aminolipids and two unidentified glycolipids. The genome of GCR10T is 4.3 Mb in length with a DNA G+C content of 36.5 mol%. Average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity values between GCR10T and Chryseobacterium piscicola VQ-6316sT were 82.1, 25.2 and 84.3 %, respectively, which clearly indicates that the novel strain is distinct from its closest relative. The demand for natural biodegradable pigments isolated frominsects, plants or microorganisms is increasing day by day because of their beneficial pharmacological properties. Here, we describe a novel strain that produces two types of pigment, carotenoid and flexirubin. On the basis of the results from phenotypic, genotypic and chemotaxonomic analyses, strain GCR10T represents a novel species of the genus Chryseobacterium, and the name Chryseobacterium caseinilyticum sp. nov. is proposed. The type strain is GCR10T (=KACC 21707T=NBRC 114715T).


Assuntos
Chryseobacterium/classificação , Oryza/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Caseínas/metabolismo , Chryseobacterium/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas , Pigmentação , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
11.
Int J Mol Sci ; 22(12)2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34203082

RESUMO

Ideal Plant Architecture 1 (IPA1) encodes SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 14 (SPL14) with a pleiotropic effect on regulating rice development and biotic stress responses. To investigate the role of IPA1 in early seedling development, we developed a pair of IPA1/ipal-NILs and found that seed germination and early seedling growth were retarded in the ipa1-NIL. Analysis of the soluble sugar content, activity of amylase, and expression of the α-amylase genes revealed that the starch metabolism was weakened in the ipa1-NIL germinating seeds. Additionally, the content of bioactive gibberellin (GA) was significantly lower than that in the IPA1-NIL seeds at 48 h of imbibition. Meanwhile, the expression of GA synthesis-related gene OsGA20ox1 was downregulated, whereas the expression of GA inactivation-related genes was upregulated in ipa1-NIL seeds. In addition, the expression of OsWRKY51 and OsWRKY71 was significantly upregulated in ipa1-NIL seeds. Using transient dual-luciferase and yeast one-hybrid assays, IPA1 was found to directly activate the expression of OsWRKY51 and OsWRKY71, which would interfere with the binding affinity of GA-induced transcription factor OsGAMYB to inhibit the expression of α-amylase genes. In summary, our results suggest that IPA1 negatively regulates seed germination and early seedling growth by interfering with starch metabolism via the GA and WRKY pathways.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Giberelinas/metabolismo , Oryza/fisiologia , Desenvolvimento Vegetal , Plântula/crescimento & desenvolvimento , Transdução de Sinais , Amido/metabolismo , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas , Germinação/genética , Fenótipo , Ligação Proteica , alfa-Amilases/metabolismo
12.
Sensors (Basel) ; 21(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202363

RESUMO

Traditional methods to measure spatio-temporal variations in above-ground biomass dynamics (AGBD) predominantly rely on the extraction of several vegetation-index features highly associated with AGBD variations through the phenological crop cycle. This work presents a comprehensive comparison between two different approaches for feature extraction for non-destructive biomass estimation using aerial multispectral imagery. The first method is called GFKuts, an approach that optimally labels the plot canopy based on a Gaussian mixture model, a Montecarlo-based K-means, and a guided image filtering for the extraction of canopy vegetation indices associated with biomass yield. The second method is based on a Graph-Based Data Fusion (GBF) approach that does not depend on calculating vegetation-index image reflectances. Both methods are experimentally tested and compared through rice growth stages: vegetative, reproductive, and ripening. Biomass estimation correlations are calculated and compared against an assembled ground-truth biomass measurements taken by destructive sampling. The proposed GBF-Sm-Bs approach outperformed competing methods by obtaining biomass estimation correlation of 0.995 with R2=0.991 and RMSE=45.358 g. This result increases the precision in the biomass estimation by around 62.43% compared to previous works.


Assuntos
Oryza , Biomassa , Produtos Agrícolas
13.
Sensors (Basel) ; 21(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203163

RESUMO

Cellulose and its derivatives have evoked much attention in sensor technology as host-matrices for conducting materials because of their versatility, renewability, and biocompatibility. However, only a few studies have dealt with the potential utilization of cellulose as a sensing material without a composite structure. In this study, cellulose nanofibers (CNF) and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibers (TOCNF) extracted from rice husks by using ultrasonic-assisted methods are introduced as a potential gas sensing material with highly sensitive performance. To fabricate nanocellulose-based films, CNF, TOCNF, and TOCNF with glycerol (TOCNF/G) were dispersed in water and applied on polyimide substrate with digital electrodes to form self-standing thin films by a drop-casting method. A transparent coating layer on the surface of the plate after drying is used for the detection of water-soluble gases such as acetone, ammonia, methane, and hydrogen sulfide gases at room temperature at 52% relative humidity. The sensor prototypes exhibited high sensitivity, and the detection limit was between 1 ppm and 5 ppm, with less than 10 min response and recovery time. The results indicate that both the CNF- and the TOCNF-coated sensors show good sensitivity toward ammonia and acetone, compared to other gases. A TOCNF/G-coated sensor exhibited minimum time in regard to response/recovery time, compared to a CNF-coated sensor. In this study, nanocellulose-based sensors were successfully fabricated using a low-cost process and a bio-based platform. They showed good sensitivity for the detection of various gases under ambient conditions. Therefore, our study results should further propel in-depth research regarding various applications of cellulose-based sensors in the future.


Assuntos
Nanofibras , Oryza , Celulose , Gases , Água
14.
Molecules ; 26(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206628

RESUMO

Black rice is a type of rice in the Oryza sativa L. species. There are numerous reports regarding the pharmacological actions of black rice bran, but scientific evidence on its gastroprotection is limited. This study aimed to evaluate the gastroprotective activities of black rice bran ethanol extract (BRB) from the Thai black rice variety Hom Nil (O. sativa L. indica) as well as its mechanisms of action, acute oral toxicity in rats, and phytochemical screening. Rat models of gastric ulcers induced by acidified ethanol, indomethacin, and restraint water immersion stress were used. After pretreatment with 200, 400, and 800 mg/kg of BRB in test groups, BRB at 800 mg/kg significantly inhibited the formation of gastric ulcers in all gastric ulcer models, and this inhibition seemed to be dose dependent in an indomethacin-induced gastric ulcer model. BRB could not normalize the amount of gastric wall mucus, reduce gastric volume and total acidity, or increase gastric pH. Although BRB could not increase NO levels in gastric tissue, the tissue MDA levels could be normalized with DPPH radical scavenging activity. These results confirm the gastroprotective activities of BRB with a possible mechanism of action via antioxidant activity. The major phytochemical components of BRB comprise carotenoid derivatives with the presence of phenolic compounds. These components may be responsible for the gastroprotective activities of BRB. The 2000 mg/kg dose of oral BRB showed no acute toxicity in rats and confirmed, in part, the safe uses of BRB.


Assuntos
Antiulcerosos , Etanol/química , Indometacina/efeitos adversos , Oryza/química , Fitoterapia , Extratos Vegetais , Úlcera Gástrica , Animais , Antiulcerosos/química , Antiulcerosos/farmacologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Indometacina/farmacologia , Masculino , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/metabolismo , Úlcera Gástrica/patologia
15.
Sensors (Basel) ; 21(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206783

RESUMO

Hyperspectral technology is used to obtain spectral and spatial information of samples simultaneously and demonstrates significant potential for use in seed purity identification. However, it has certain limitations, such as high acquisition cost and massive redundant information. This study integrates the advantages of the sparse feature of the least absolute shrinkage and selection operator (LASSO) algorithm and the classification feature of the logistic regression model (LRM). We propose a hyperspectral rice seed purity identification method based on the LASSO logistic regression model (LLRM). The feasibility of using LLRM for the selection of feature wavelength bands and seed purity identification are discussed using four types of rice seeds as research objects. The results of 13 different adulteration cases revealed that the value of the regularisation parameter was different in each case. The recognition accuracy of LLRM and average recognition accuracy were 91.67-100% and 98.47%, respectively. Furthermore, the recognition accuracy of full-band LRM was 71.60-100%. However, the average recognition accuracy was merely 89.63%. These results indicate that LLRM can select the feature wavelength bands stably and improve the recognition accuracy of rice seeds, demonstrating the feasibility of developing a hyperspectral technology with LLRM for seed purity identification.


Assuntos
Oryza , Algoritmos , Modelos Logísticos , Sementes , Tecnologia
16.
BMC Plant Biol ; 21(1): 308, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193032

RESUMO

BACKGROUND: Rice (Oryza sativa L.) Chalkiness, the opaque part in the kernel endosperm formed by loosely piled starch and protein bodies. Chalkiness is a complex quantitative trait regulated by multiple genes and various environmental factors. Phytohormones play important roles in the regulation of chalkiness formation but the underlying molecular mechanism is still unclear at present. RESULTS: In this research, Xiangzaoxian24 (X24, pure line of indica rice with high-chalkiness) and its origin parents Xiangzaoxian11 (X11, female parent, pure line of indica rice with high-chalkiness) and Xiangzaoxian7 (X7, male parent, pure line of indica rice with low-chalkiness) were used as materials. The phenotype, physiological and biochemical traits combined with transcriptome analysis were conducted to illustrate the dynamic process and transcriptional regulation of rice chalkiness formation. Impressively, phytohormonal contents and multiple phytohormonal signals were significantly different in chalky caryopsis, suggesting the involvement of phytohormones, particularly ABA and auxin, in the regulation of rice chalkiness formation, through the interaction of multiple transcription factors and their downstream regulators. CONCLUSION: These results indicated that chalkiness formation is a dynamic process associated with multiple genes, forming a complex regulatory network in which phytohormones play important roles. These results provided informative clues for illustrating the regulatory mechanisms of chalkiness formation in rice.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Oryza/genética , Oryza/fisiologia , Reguladores de Crescimento de Plantas/farmacologia , Transcrição Genética/efeitos dos fármacos , Endosperma/efeitos dos fármacos , Endosperma/metabolismo , Endosperma/ultraestrutura , Perfilação da Expressão Gênica , Ontologia Genética , Oryza/efeitos dos fármacos , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reprodutibilidade dos Testes , Amido/metabolismo , Amido/ultraestrutura , Sacarose/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
BMC Plant Biol ; 21(1): 306, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193042

RESUMO

BACKGROUND: Outbreaks of insect pests in paddy fields cause heavy losses in global rice yield annually, a threat projected to be aggravated by ongoing climate warming. Although significant progress has been made in the screening and cloning of insect resistance genes in rice germplasm and their introgression into modern cultivars, improved rice resistance is only effective against either chewing or phloem-feeding insects. RESULTS: In this study, the results from standard and modified seedbox screening, settlement preference and honeydew excretion tests consistently showed that Qingliu, a previously known leaffolder-resistant rice variety, is also moderately resistant to brown planthopper (BPH). High-throughput RNA sequencing showed a higher number of differentially expressed genes (DEGs) at the infestation site, with 2720 DEGs in leaves vs 181 DEGs in sheaths for leaffolder herbivory and 450 DEGs in sheaths vs 212 DEGs in leaves for BPH infestation. The leaf-specific transcriptome revealed that Qingliu responds to leaffolder feeding by activating jasmonic acid biosynthesis genes and genes regulating the shikimate and phenylpropanoid pathways that are essential for the biosynthesis of salicylic acid, melatonin, flavonoids and lignin defensive compounds. The sheath-specific transcriptome revealed that Qingliu responds to BPH infestation by inducing salicylic acid-responsive genes and those controlling cellular signaling cascades. Taken together these genes could play a role in triggering defense mechanisms such as cell wall modifications and cuticular wax formation. CONCLUSIONS: This study highlighted the key defensive responses of a rarely observed rice variety Qingliu that has resistance to attacks by two different feeding guilds of herbivores. The leaffolders are leaf-feeder while the BPHs are phloem feeders, consequently Qingliu is considered to have dual resistance. Although the defense responses of Qingliu to both insect pest types appear largely dissimilar, the phenylpropanoid pathway (or more specifically phenylalanine ammonia-lyase genes) could be a convergent upstream pathway. However, this possibility requires further studies. This information is valuable for breeding programs aiming to generate broad spectrum insect resistance in rice cultivars.


Assuntos
Herbivoria/fisiologia , Oryza/genética , Oryza/parasitologia , Floema/parasitologia , Folhas de Planta/parasitologia , Transcriptoma/genética , Animais , Parede Celular/metabolismo , Ciclopentanos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Hemípteros/fisiologia , Metabolismo dos Lipídeos , Oxilipinas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Ácido Salicílico/metabolismo , Ácido Chiquímico/metabolismo , Transcrição Genética
18.
Int J Mol Sci ; 22(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199720

RESUMO

The underground reserve (root) has been an uncharted research territory with its untapped genetic variation yet to be exploited. Identifying ideal traits and breeding new rice varieties with efficient root system architecture (RSA) has great potential to increase resource-use efficiency and grain yield, especially under direct-seeded rice, by adapting to aerobic soil conditions. In this review, we tried to mine the available research information on the direct-seeded rice (DSR) root system to highlight the requirements of different root traits such as root architecture, length, number, density, thickness, diameter, and angle that play a pivotal role in determining the uptake of nutrients and moisture at different stages of plant growth. RSA also faces several stresses, due to excess or deficiency of moisture and nutrients, low or high temperature, or saline conditions. To counteract these hindrances, adaptation in response to stress becomes essential. Candidate genes such as early root growth enhancer PSTOL1, surface rooting QTL qSOR1, deep rooting gene DRO1, and numerous transporters for their respective nutrients and stress-responsive factors have been identified and validated under different circumstances. Identifying the desired QTLs and transporters underlying these traits and then designing an ideal root architecture can help in developing a suitable DSR cultivar and aid in further advancement in this direction.


Assuntos
Adaptação Fisiológica/fisiologia , Oryza/fisiologia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/fisiologia , Sementes/fisiologia , Germinação/fisiologia , Oryza/genética , Oryza/crescimento & desenvolvimento , Locos de Características Quantitativas/genética , Sementes/genética , Sementes/crescimento & desenvolvimento
19.
BMC Plant Biol ; 21(1): 313, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215178

RESUMO

BACKGROUND: Harnessing heterosis is one of the major approaches to increase rice yield and has made a great contribution to food security. The identification and selection of outstanding parental genotypes especially among male sterile lines is a key step for exploiting heterosis. Two-line hybrid system is based on the discovery and application of photoperiod- and thermo-sensitive genic sensitive male sterile (PTGMS) materials. The development of wide-range of male sterile lines from a common gene pool leads to a narrower genetic diversity, which is vulnerable to biotic and abiotic stress. Hence, it is valuable to ascertain the genetic background of PTGMS lines and to understand their relationships in order to select and design a future breeding strategy. RESULTS: A collection of 118 male sterile rice lines and 13 conventional breeding lines from the major rice growing regions of China was evaluated and screened against the photosensitive (pms3) and temperature sensitive male sterility (tms5) genes. The total gene pool was divided into four major populations as P1 possessing the pms3, P2 possessing tms5, P3 possessing both pms3 and tms5 genes, and P4 containing conventional breeding lines without any male sterility allele. The high genetic purity was revealed by homozygous alleles in all populations. The population admixture, principle components and the phylogenetic analysis revealed the close relations of P2 and P3 with P4. The population differentiation analysis showed that P1 has the highest differentiation coefficient. The lines from P1 were observed as the ancestors of other three populations in a phylogenetic tree, while the lines in P2 and P3 showed a close genetic relation with conventional lines. A core collection of top 10% lines with maximum within and among populations genetic diversity was constructed for future research and breeding efforts. CONCLUSION: The low genetic diversity and close genetic relationship among PTGMS lines in P2, P3 and P4 populations suggest a selection sweep and they might result from a backcrossing with common ancestors including the pure lines of P1. The core collection from PTGMS panel updated with new diverse germplasm will serve best for further two-line hybrid breeding.


Assuntos
Oryza/genética , Fotoperíodo , Infertilidade das Plantas/genética , Sementes/genética , Temperatura , Núcleo Celular/genética , Núcleo Celular/efeitos da radiação , Análise por Conglomerados , Ontologia Genética , Estudos de Associação Genética , Marcadores Genéticos , Luz , Nucleotídeos/genética , Oryza/efeitos da radiação , Filogenia , Infertilidade das Plantas/efeitos da radiação , Polimorfismo de Nucleotídeo Único/genética , Análise de Componente Principal , Reprodutibilidade dos Testes , Sementes/efeitos da radiação
20.
Plant Physiol Biochem ; 165: 239-250, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34082330

RESUMO

Melatonin mediates multiple physiological processes in plants and is involved in many reactions related to the protection of plants from abiotic stress. In this paper, the effect of melatonin on the antioxidant capacity of rice under salt stress was studied. Melatonin alleviated the inhibition of salt stress on the growth of rice seedlings, mainly by increasing the dry weight and fresh weight of shoots and roots. Melatonin alleviated the membrane damage caused by salt stress, which was mainly manifested by the decrease of TBARS content and the decrease of leaf and root damage. During the whole salt stress period, rice after melatonin pretreatment showed lower ROS (H2O2, O2•-,OH-) accumulation. In the early stage (1-3 d) of stress, the rice after melatonin pretreatment showed a strong increase in antioxidant enzyme activity, while in the later stage (5,7 d), it showed a strong increase in antioxidant content. During the whole period of salt stress, melatonin had a weak regulatory effect on AsA-GSH cycle. Through the above regulation process, the decreasing effect of melatonin on ROS content of rice under salt stress did not decrease with prolonged stress time in a short time (1-7 d). In conclusion, melatonin improved the antioxidant capacity of rice under continuous salt stress, and rice showed variable antioxidant strategies after melatonin pretreatment.


Assuntos
Melatonina , Oryza , Antioxidantes , Peróxido de Hidrogênio , Melatonina/farmacologia , Estresse Salino , Plântula , Estresse Fisiológico
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