2020 Vol. 35, No. 6
Display Method:
2020, 35(6): 576-581.
doi: 10.19303/j.issn.1008-0384.2020.06.002
Abstract:
Objectives A new blast-resistant lines of rice suitable for cultivation in Fujian province was generated with an efficient breeding method. Methods Applying the EMS chemical mutagenesis, Hang 2 with excellent agronomic traits except blast-resistance was selected to breed a hybrid restorer line through directional cultivations in areas with varied ecological conditions. Disease-resistance of the lines was verified to finalize the process and hybrid selection. Results The hybrid Indica restorer line, Fuhui 7076, not only inherited the desirable agronomic traits of Hang 2, such as wide compatibility, strong resilience, and high combining ability, but also performed superior on the quality and yield as well as an MR (medium resistance) rating on blast. Utilizing Fuhui 7076 to cross with Ganxiang A, Ganyou 7076 gave a 2-year average yield of 10,711.5 kg/hectare at the 2015 and 2016 Yunnan Provincial Indica Hybrid Rice Trials. The yield was 3.24%, and the rate of increase 68.42%, higher than control, F You 498. In 2017 , Ganyou 7076 was certified by the Crop Certification Committee of Yunnan Province (Certificate No. 2017009). Conclusions With the EMS chemical mutagenesis, the agronomically desirable Hang 2 was bred to be blast-resistant. Through years of continued directional selection in blast-prone rice farming regions of varied ecosystems, the time required for natural mutation process was significantly shortened in the breeding of the disease-resistant variety.
2020, 35(6): 582-590.
doi: 10.19303/j.issn.1008-0384.2020.06.003
Abstract:
Objective To clarify the effects of different interaction factors (aboveground interaction, root competition, soil environment improvement) on crop-yields under maize and legumes intercropping systems. Method Maize/soybean and maize/peanut were intercropped with no separation, with a net-barrier or with a physical barrier to completely separate the involved maize and legume plants. In addition, maize, soybean, and peanut were also planted as monocrop at the testing fields for comparison. Interspecies competition or synergy, such as the aboveground plant interactions and underground root competition, and soil improvements induced by the treatments on crop-yields of the two systems were analyzed. Result Intercropping maize and legume plants increased the combined crop-yield over the monocropping, despite the treatment differences. In an intercropping system, maize was most competitive of the 3 crops with respect to the aboveground growth, while peanut the least. The maize yield under the maize/soybean system increased with a contribution rate of 15.83% by the aboveground interactions, and 15.98% under the maize/peanut cultivation. The peanut yield, meanwhile, was suppressed by 11.42% when intercropped with maize. In contrast to the aboveground plant interactions, the root competition exerted negative effects on the yields of both species under the maize/soybean system that resulted in a reduction of 2.87% on maize, 5.35% on soybean, and 4.52% on total yield. For the intercropped maize and peanut plants, the root competition raised the maize yield by 5.88% and 0.8% on the combined yield. The intercropping improved soil conditions that facilitated crop-yield and production stability in both systems. Conclusion The morphology and physiology of the maize, soybean, and peanut plants appeared to cause the variations on the effects on crop-yield by the intercropping. Meanwhile, the soil eco-system was improved by the practice contributing significantly to the yield and production stability. A quantified relationship between intercropping and crop-yield as illustrated by this study could be applied to optimize other agricultural planning and management as well.
2020, 35(6): 591-597.
doi: 10.19303/j.issn.1008-0384.2020.06.004
Abstract:
Objective Orthogonal tests on temperature, time and varieties were conducted for the effects of emasculation technology by hot water in this study, which contributed to explore the suitable emasculation schemes of female parents, reduce self-fertilization ratio and improve the hybrid seed fertility of sugarcane tassels. Method The tassels of ROC22, Ke 5 and Guitang 02-619 with numerous pollen were treated at 48℃, 50℃ and 52℃ for 3 min, 5 min and 7 min according to the design scheme from L9 (34) orthogonal table. Among 6 tassels (one tassel per plant), 3 tassels were self-pollinated and the other 3 tassels were cross-pollinated (fresh exogenous pollen was granted artificially), the results of which were analyzed to calculate the emergence rate of self-pollinated and cross-pollinated hybrids. Result The emergence rate of ROC22, Ke 5 and Guitang 02-619 were gradually decreased with the increasing of temperature and time, and the ratio of pseudohybrids appeared to change with fluctuating. In addition, the pseudohybrids ratio was lowest (0.12) when cultivars were treated at 50℃ for 3 min. The variance analysis results showed that emergence number of self-pollinated seeds/emergence number of outcrossed seeds (M value) can be used to identify the effects of emasculation technology by hot water, the effect of emasculation technology by hot water was more significant when M value was higher. The temperature and time influenced on M value significantly, but different varieties had no difference. Conclusion The emasculation effect of sugarcane tassels being treated at 50℃ for 3min was better when the unspread branches and mature or being mature branches were removed before tassel emasculation, which significantly increased the seed setting percentage of hybridization.
2020, 35(6): 598-610.
doi: 10.19303/j.issn.1008-0384.2020.06.005
Abstract:
Objective Base on transcriptome sequencing, the molecular mechanisms that caused the secondary metabolic differences between the leaves and roots of Sarcandra glabra were studied for clinic applications of the two parts, as well as for determination of the effective components in the medicinal herb. Method Specimens of S. glabra were collected from Fuzhou, Fujian for a transcriptome analysis on the leaves and roots using the Illumina HiSeq platform. After filtration and the Trinity assembly, the unigenes were compared with Nr, Nt, Pfam, KOG, Swiss-Prot, KEGG, and GO by BLAST, and the differentially expressed genes analyzed. A special attention was paid on the differentially enriched genes in the KEGG metabolic pathway. Result More than 40 million clean reads were obtained from the sequencing. The Trinity assembly yielded 508 271 unigenes with an average length of 740 bp. Based on BLAST, 148 561 unigenes, accounting for 58.80% of the total, were successfully annotated using 7 functional annotation databases. There were 29 732 unigenes identified with differential gene expressions between the leaves and the roots. Of which, 12 511 were up-regulated and 17 221 down-regulated. Dozens of significantly different KEGG metabolic pathways were found that associated with functions such as starch/sucrose metabolism, phenylpropanoid biosynthesis, glyoxylate/dicarboxylate metabolism, carbon fixation in photosynthetic organisms, phagosome/glutathione metabolism, photosynthesis, alanine/aspartate/glutamate metabolism, sesquiterpenoid/triterpenoid biosynthesis, porphyrin/chlorophyll metabolism, nitrogen metabolism, circadian rhythm-plant/photosynthesis-antenna proteins, stilbenoid/diarylheptanoid/gingerol biosynthesis, unsaturated fatty acids biosynthesis, limonene/pinene degradation, carotenoid biosynthesis, diterpenoid biosynthesis, flavonoid biosynthesis, fatty acid elongation, etc. Insofar as pharmacodynamics is concerned, the secondary metabolic pathway of the phenylpropanoid biosynthesis had 193 differentially expressed genes between the leaves and the roots, that of the sesquiterpene/triterpene biosynthesis 82, that of the diterpene biosynthesis 40, and that of the flavonoid biosynthesis 35. In addition, the up-regulated genes of sesquiterpene synthase, ent-kaur-16-ene synthase, and flavonol synthase/flavanone 3-hydroxylase, as well as the down-regulated genes of 8-hydroxygeraniol dehydrogenase, vinornine synthase, and squalene synthase were found significantly different between the two parts. Conclusion The genes related to the secondary metabolic pathways of phenylalanine sesquiterpenoid and triterpenoid, diterpenes, and flavonoids most significantly differed in leaves and roots of S. glabra. The significantly differentiated genes associated with the key enzymes provided important information for analyzing the molecular mechanisms of the medicinal herb.
2020, 35(6): 611-617.
doi: 10.19303/j.issn.1008-0384.2020.06.006
Abstract:
Objective By studying changes on the agronomic properties of Brassica chinensis L. in response to the light and temperature conditions in a greenhouse, morphology and yield of the plant were investigated. Method A hydroponics experiment with a heat-resistant B. chinensis in a greenhouse was carried out. The environmental data were collected in real time, and the agronomic properties of the plants monitored continuously. Relationship between the plant agronomy and the greenhouse temperature and photosynthetically active radiation (or, the light and temperature function, LTF) was used to compare with other dynamic simulation models. Result The agronomic indices including plant height, leaf number, leaf area, stem diameter, root length, and fresh weight of B. chinensis increased with increasing LTF in a fitting equation of an s-shaped function. Prediction by the LTF-based model was better than either TEP- or GDD-based model. The LTF model was not only more precise but also better fitted between the simulated and measured agronomic indices. It showed a R2 of 0.907-0.984, a RMSE of 0.540-34.393, and a RE of 6.79-12.66%, which were superior to the RMSE and RE of 5.29-59.98% and 31.30-96.23% for TEP and GDD models, respectively. Conclusion The LTF-based model was found to more accurately predict the growth and yield of B. chinensis than did the other models.
2020, 35(6): 618-625.
doi: 10.19303/j.issn.1008-0384.2020.06.007
Abstract:
Objective Using the protein on coat of MS2 bacteriophage as a carrier, chimeric nanoparticles with a linear epitope of porcine reproductive and respiratory syndrome virus, GP5, were constructed, and their immunogenicity determined. Method The dominant neutralizing epitope gene sequence on GP5 was inserted into the MS2 protein by overlapping extension PCR. The recombinant vector was to express the chimeric protein through a prokaryotic expression system. The target protein was purified by ammonium sulfate precipitation and gel filtration chromatography followed by characterization with dynamic light scattering and electron microscopy. The immunogenicity of the constructed chimeric nanoparticles was determined by Western blot and animal immunoassay. Result The linear epitope was successfully inserted into the target sequence, and the recombinant vector reached a purity greater than 85%. The purified target protein self-assembled in vitro to form uniform chimeric nanoparticles with a diameter of 25–31 nm. After immunizing animals, the chimeric particles produced a high-level of antibodies that reacted with inactivated viruses showing significant immunogenicity. Conclusion The MS2 phage coat protein allowed the insertion of 9 exogenous polypeptides (the linear epitope on GP5) and self-assembled in vitro to form the chimeric virus-like particles. Each particle carried the exogenous polypeptides on the surface generating high immunogenicity. The current technology provided a new venue for building other epitopes of porcine reproductive and respiratory syndrome virus or epitopes with longer tandem.
2020, 35(6): 626-632.
doi: 10.19303/j.issn.1008-0384.2020.06.008
Abstract:
Objective A mutant rice showing signs of early senescence on leaves and susceptibility to rice blast and blight was used for phenotypic and genetic analyses to study the genes associated with the aging mechanism and vulnerability to the diseases of rice plants. Method Resistance to blast and bacterial blight of the mutant rice w14 with symptoms of early senescence was tested by artificial inoculation. Phenotype classification of the mutant was determined by chlorophyll content measured in vitro under induced darkness. Expressions of the genes related to senescence and pathogenesis in the mutant and wild-type japonica rice variety, Yunyin (YY), were compared. Result After inducing darkness for 24h, the chlorophyll content in w14 was 5% lower than that in YY, and the difference reached a 1% statistical significance level in 48 h. The expressions of senescence-related genes SGR, Osh36, Osh69, PAO, NYC3, and RCCR1 in w14 were significantly higher than those in the wild-type counterpart. The mutant rice was more susceptible to the artificial inoculations of rice blast and bacterial blight, and the pathogenesis-related genes PR1a, PR4, Cth1, PR1b, PBZ1, and PR3 significantly up-regulated in w14 than in YY. Conclusion The mutant rice w14 showed the typical senescence phenotypes with a higher susceptibility to rice blast and bacterial blight than the wild-type YY. The expressions of pathogenesis-related genes in the mutants were significantly altered that substantially affected its defense system leading to the early senescence and disease susceptibility as observed in the study.
2020, 35(6): 640-648.
doi: 10.19303/j.issn.1008-0384.2020.06.010
Abstract:
Objective A survey was conducted to determine the quality of the commercial organic fertilizers produced in Fujian. Method Fifty representative organic fertilizers were sampled in areas of Nanping, Zhangzhou, Longyan, Sanming, and Fuzhou during July to September 2019. Contents of nutrients and heavy metals of the specimens were determined. Result According to the national standards for organic fertilizers in China NY 525—2012, 8% of the samples failed to meet the standard on pH, 10% on organic matters, 28% on total NPK, and 32% on moisture content. Heavy metals, including Pb, Cd, Cr, Hg, and As, were detected in all samples but did not exceed the safety limits. The organic fertilizers made of biomass were significantly higher on K and total nutrients (NPK) than other organic ingredients. Those of livestock manure-origins were higher on heavy metals, except Hg, than the others. The fertilizers made of pig manure were significantly higher in the contents of N, P and total nutrients than those made of chicken or sheep manure. Among the heavy metals, Cr was highest in the pig manure fertilizer, followed by the chicken and sheep manure fertilizers. And, Pb, Cd, Hg, and As were highest in the chicken manure fertilizer, which contained significantly more As than the sheep or pig counterparts. Conclusion Heavy metals in the sampled organic fertilizers produced in the province did not exceed the national standards. However, the nutrient contents tended to be substandard, and the moisture content too high. The deficiency on NPK of these products was particularly alarming that proper measures should be implemented for adequate fertilization applications.
2020, 35(6): 649-656.
doi: 10.19303/j.issn.1008-0384.2020.06.011
Abstract:
Objective Improvement effects of straw returning and mixed purple soils was studied to form efficient remediation technology of sandy acid soil and yield & quality of flue-cured tobacco. Method Field experiments were conducted to find the effects of the straw returning and mixed purple soils on physicochemical properties of soil, yield & quality of flue-cured tobacco, which were: no straw and purple soils added as control (T1,CK), straw returning (T2, 3 000 kg·hm−2), mixed purple soils (T3,225 m3·hm−2), straw returning (3 000 kg·hm−2)+ mixed purple soils (225 m3·hm−2) (T4). Result Treatments of straw returning and mixed purple soils could improve the soil physical properties. Compared with CK, the soil bulk density were decreased by 6.38%, 2.12 % for T2 and T4,while the soil particle size composition transformed from clayey loam (CK) to loam (T2), silty loam (T3 and T4). Compared with CK, the soil pH, organic matter and Avail. N were significantly improved by T2; the soil pH and available potassium were increased by 1.43 and 19.98 mg·kg−1, respectively. The remarkable improvement of chemical properties of soil was T4, which the pH value, organic matter and available potassium content of tobacco planting soil were 1.21, 1.26 and 1.28 times higher than those of T1 (CK), respectively. Treatments of straw returning and mixed purple soils even could promote the growth of tobacco, improve the economic benefits and quality of flue-cured tobacco. The best effect on economic characteristics of tobacco, chemical composition coordination and sensory evaluation quality in grade C3F of flue-cured tobacco leaves was T4, the yield, output and the proportion of high quality of which increased by 35.04 %, 20.64 % and 38.59 % ,respectively. Conclusion The best improvement effects of acid soil was straw returning (3 000 kg·hm−2) cooperated with mixed purple soils (225 m3·hm−2). It can effectively improve the physical properties, pH value, organic matter and available potassium content of soil, then achieve economic returns from both sides of tobacco leaves’ yield & quality and the sustainable remediation of sandy acid soil.
2020, 35(6): 657-664.
doi: 10.19303/j.issn.1008-0384.2020.06.012
Abstract:
Objective A microorganism capable of decomposing malachite green (MG) was identified and its degradation ability studied. Method Indigenous microbes in water samples from aquaculture farms were enriched and domesticated in laboratory to screen for the species that could degrade the organic germicide, MG, a pollutant in aquaculture ponds. Strains showing such capability by physiological and biochemical tests were examined under scanning electron microscopy and identified by a 16S rDNA analysis. A single factor experiment was conducted to determine the effects of temperature, pH, and initial MG concentration on the degradation kinetics of the isolated bacterium. The inoculated culture medium was monitored continuously for the luminescent bacteria toxicity determination and sampled for the high-resolution mass spectrometry analysis to reveal the decomposition pathway. Result An MG-degrading bacterium isolated from the specimens collected at a fish pond in Shanghai was identified as D3 belonging to Citrobacter sp. It exhibited a high rate of growth and MG-degradation on the medium at the pH ranging from 7 to 8 and temperature between 30℃ and 35℃. Its degradation rate under MG 2 mg·L−1 was 96.32% and a half-life of 0.563 0 d with no significant accumulation of leucomalachite green (LMG). Once the MG concentration exceeded 30 mg·L−1, the bacterial growth and degradation effect were significantly hindered. The first-order kinetic degradation function of D3 had a correlation coefficient of 0.916 9–0.963 5. After inoculation for 72 h, the overall toxicity shown on the medium was significantly decreased with more than 50% reduction on the inhibition of the luminescent bacterial growth. Three compounds, 4-dimethylaminodiphenyl ketone (m/z=226.12), N, N-dimethylaniline (m/z=122.10), and 4-dimethylamino-phenol (m/z=138.09), in the metabolites were the degradation intermediates. It appeared that D3 removed the benzene rings in MG step by step to result in those degraded secondary metabolites. Conclusion D3 of Citrobacter sp. might be applied to decontaminate MG in aquaculture ponds.
2020, 35(6): 665-672.
doi: 10.19303/j.issn.1008-0384.2020.06.013
Abstract:
Objective A process of extracting sialic acid from chicken small-intestine mucosa was optimized for the utilization of a broiler processing byproduct. Method A single factor experiment was conducted to select appropriate acid for the extraction. Then, a 3-factors Box-Behnken test was designed to optimize the acid concentration, time, and liquid-to-material ratio in extracting sialic acid from chicken intestinal mucosa. Result Seventeen experiments were performed in triplicate to arrive at the optimized process that utilized citric acid at a concentration of 0.1 mol·L−1 in a liquid-to-material ratio of 32.20 ∶ 1 (mL·g−1), which was simplified to 30 ∶ 1 (mL·g−1), to extract for 4 h. The resulting extract contained sialic acid (1 010.39±21.87) μg·g−1, which was close to the targeted goal of 1 025.69 μg·g−1. Conclusion The optimized sialic acid extraction from chicken small-intestine mucosa provided a new venue for byproduct utilization and waste reduction in poultry processing.
2020, 35(6): 673-681.
doi: 10.19303/j.issn.1008-0384.2020.06.014
Abstract:
Objective Polyphenol compounds in purple cowpeas were solvent-extracted, purified, and then chemically analyzed by HPLC. Method Single factor and orthogonal experiments were conducted to optimize the polyphenol extraction from purple cowpeas. Using polyphenol yield as the criterion, effects of solvent, solid-liquid ratio, temperature, and pH applied for the process were evaluated for optimization. The crude extract was purified using a Sephadex LH-20 macroporous resin. HPLC with external standards was employed for the chemical determination on the purified product. Result The optimized process applied a peas-to-solvent ratio of 1 ∶ 5 (m ∶ V) with an 80% acetone solution to extract 3 times at 4oC and pH 6 for 5 h per cycle to reach a maximum total polyphenols content of the gallic acid equivalent of 614 mg·100 g−1. The correlation coefficients on the linear functions of the 6 polyphenols against their respective standards ranged from 0.995 9 to 0.999 9 with a limit of detection (LOD) of 0.1～1.0 mg·100 g−1 and that of quantitation 0.2～2.5 mg·100 g−1 on the HPLC test. The average recoveries on these compounds ranged from 74.3% to 107% with a relative standard deviation (RSDs) of 0.4～8.6%. The 6 polyphenols in the purple cowpeas thus determined averaged between 0.46 mg·100 g−1 and 6.5 mg·100 g−1, with rutin being the most abundant.ing the most abundant. Conclusion The polyphenol extraction from purple cowpeas was optimized to deliver high yields on 6 monomer phenols, which could be accurately determined quantitatively by HPLC.
2020, 35(6): 682-690.
doi: 10.19303/j.issn.1008-0384.2020.06.015
Abstract:
Objective Extracting polyphenols from peels of coffee beans (Coffea arabica L.) was optimized, and antioxidant activity of the extract determined. Method Single factor and response surface experiments were conducted to optimize the ultrasound-assisted extraction process. Antioxidant capacity of the polyphenols obtained was determined by an in vitro method. Result The optimized process applied a solid-to-liquid ratio of 1 ∶ 54 (g ∶ mL) and the ethanol concentration of 56% to extract at 69oC for 42 min. The polyphenols content in the extract reached 34.68 mg·g−1. The IC50 of the extract was 2.10 μg·mL−1 on 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals, 314.97 μg·mL−1 on hydroxyl free radicals, and 322.02 μg·mL−1 on superoxide anion free radicals. The scavenging effect of the extracted polyphenols was 0.99 times of that of L-ascorbic acid on DPPH free radicals, 0.52 times on hydroxyl free radicals, and 0.12 times on superoxide anion free radicals. Conclusion The optimized polyphenol extraction process produced extract with significant antioxidant activity and could be applied to utilize the byproduct for the coffee industry.
