2019 Vol. 34, No. 12
Display Method:
2019, 34(12): 1364-1370.
doi: 10.19303/j.issn.1008-0384.2019.12.002
Abstract:
Objective To explore the application of single imprinted QTL mapping based on random mating of natural populations and analyze key factors affecting the mapping accuracy. Method Assuming the trait determined by the imprinted QTL to be quantitative and a linear relationship between the trait and the markers existed, then the least squares method could be used to estimate the QTL mapping and genetic parameters. The imprinted QTL mapping was generated by computer simulating the single-point markers as well as a real data set of natural population markers. The statistical power and parameter estimation accuracy of different genotype frequencies, heritability rates, and random mating rounds were compared. The significance of imprinted QTLs was determined by using F- and t-tests. Result Through a simulation study, it was proven that the experimental design was effective in detecting a single imprinted QTL. When the MAF was greater than 5% and the imprinted heritability greater than 10%, the iQTLs positions and genetic parameters were presumably unbiased Conclusion Using random mating in the nature to generate mapping populations could conceivably be used to locate single-imprinted QTLs with acceptable results of localization. It seemed to be an effective design for the next step for QTL mapping.
2019, 34(12): 1371-1378.
doi: 10.19303/j.issn.1008-0384.2019.12.003
Abstract:
Objective Seed sterilization and rooting culture are important steps in plant tissue culture. At present, there is considerable variation in the concentration of sodium hypochlorite (NaClO) and seed sterilization time of Brassica napus, as well as the type and concentration of hormone in the rooting media. The purpose of this study was to optimize the method of seed sterilization with NaClO and the formula of rooting medium for B. napus regeneration. Method The optimum concentration of NaClO for seed sterilization was screened by comparing the growth status (such as germination rate, healthy shoot rate and rate of colonies) of seeds treated with different concentrations (0.1%–30.0%) of NaClO, and the appropriate sterilization time was optimized based on the growth status of seeds treated with the optimal concentration of NaClO for 10—30 min. Moreover, the optimum formula of rooting media was screened by comparing the rooting regeneration of seedlings in the media containing 0.1–2.0 mg·L−1 naphthylacetic acid (NAA) / indolebutyric acid (IBA). Result The optimum concentration of NaClO for seed sterilization was 2.0% or 3.0%, and the best time for seed sterilization with 3.0% NaClO was 15 min, causing the 97.4% of germination rate and 85.9% of healthy shoot rate with least rate of colonies. Moreover, this method of seed sterilization is applicable to other 9 plants, especially for B. napus, B. pekinensis and Arabidopsis thaliana. The root regenerated best in the rooting medium containing 0.1 mg·L−1 NAA, in which 92.5% of root regenerated from the cutting point on the 7th day with the most lateral roots. Conclusion This study optimized the method of seed sterilization and the formula of rooting medium, which laid a foundation for efficient plant tissue culture of B. napus.
2019, 34(12): 1379-1387.
doi: 10.19303/j.issn.1008-0384.2019.12.004
Abstract:
Objective Diversity on the agronomic traits relating to breeding purpose of arabica coffee germplasms in collection was studied. Method From 60 arabica coffee germplasms, 8 agronomic and 5 quality traits were targeted and subjected them to the correlation, principal component, and cluster analyses for the genetic diversity study. Result Among the 8 agronomic traits, the fresh/dry ratio had the highest coefficient of variation of 25.15% followed by fresh fruit weight of 19.85%, while green bean rate of 1.97% being the lowest. Seed length ranked the highest on the genetic diversity indices. On the 5 quality traits, the chlorogenic acid content showed the highest coefficient of variation of 22.68% followed by fat of 12.40%, and protein of 5.20% being the lowest of all. Chlorogenic acid also had the greatest genetic diversity index of 2.07 followed by fat of 2.06 and protein of 2.05. The dry bean weight of the germplasms significantly correlated with their green bean rate; the seed size with 100-seed weight, green bean rate and protein; the 100-seed weight with green bean rate, protein and fat; and, the green bean rate with protein and fat. The contents of protein and fat showed an extremely significant correlation; whereas, those of caffeine and sucrose an extremely significant inverse correlation. The principal component analysis indicated the top 4 main components (i.e., PC1-PC4) included the 12 agronomic traits and had a combined contribution of 69.17% of the total constituting the major factors that affected the diversity. A cluster analysis classified the 60 germplasms into two groups, 53 in Group I and 7 in Group II. Group II was high on the fresh fruit weight, especially, Subgroup II-2, which exhibited high fresh and dry bean weights. Conclusion The arabica coffee germplasms under study were rich in diversity. The desirable genes could be preserved by domestication, hybridization, grafting and/or molecular breeding. Subgroup II-2, being high on fresh and dry bean weights, could conceivably be used as a parent for new variety breeding.
2019, 34(12): 1388-1396.
doi: 10.19303/j.issn.1008-0384.2019.12.005
Abstract:
Objective To optimize the fertilization for improving fig quality and yield, the internal regulation mechanism of potassium (K) on sugar metabolism of the fruit was studied. Method Two-year-old Bojihong fig (Ficus carica) plants were cultivated under common practice, except that 4 levels of K2SO4 were applied on the soil for the experimentation. The K applications included CK at 0g.plant−1, K1 at 125 g.plant−1, K2 at 250 g.plant−1, and K3 at 375 g.plant−1. Contents of soluble sugars and starch as well as activities of enzymes related to the sugar metabolism of the fruits were determined for a correlation analysis. Result (1) Fructose and glucose were the main soluble sugars contained in the fruit with the contents increased as the fruit was developing. The combined starch and soluble sugars content decreased with fruit maturation, and the starch declined while the sugars on the rise. (2) With the K applications, both the contents and the compositions of the of soluble sugars in the figs significantly increased, while starch decreased during the mid and late stages of the fruit development. K2 produced the greatest soluble sugars increase among all treatments. (3) The K applications significantly rose the activities of AI and SS (in the starch degradation direction), but not on NI, in the early and late stages of the fruit development. However, they extremely significantly enhanced the NI activity as the fruits matured resulting in fructose and glucose accumulations in the figs. They also boosted, and maintained at high level, on the activities of α- and β-amylases facilitating the conversion of starch to sugars. In addition, the K applications promoted SPS activity in all developmental stages but exerted little effect on SS (in the synthesis direction) that encouraged the sucrose formation n the fruit. Conclusion The K applications increased activities of the enzymes related to sugar metabolism and promoted starch degradation that benefitted the accumulation of desirable soluble sugars in figs.
2019, 34(12): 1397-1403.
doi: 10.19303/j.issn.1008-0384.2019.12.006
Abstract:
Objective A cold-injury index for Camellia sinensis cv. Fuding-dabaicha, the major tea cultivars in Guizhou, was established to provide the meteorological information for precision insurance actuary and agro services on the crop. Method Physiological indices that reflect the growth of the tea plants under simulated low-temperatures in an artificial climate chamber were monitored. Semi-lethal temperature of the plants by cold stress was mathematically determined on a logistic function between the rate of injured cell and treatment temperature. Result With the lowering temperature, the physiological responses of the plants showed a gradually increased SOD activity, initially raised and then declined MDA, and continuously increased relative electric conductivity. The semi-lethal temperature of the plants differed depending upon the duration of cold treatment. The longer the plants were exposed to the chill, the higher the semi-lethal temperature became. When the cold lasted for 3 d, 5 d, and 7 d, the semi-lethal temperatures rose to 1.5℃, 1.8℃, and 2.6℃, respectively. Conclusion The growth responses of C. sinensis under low-temperature closely related to severity as well as duration of the exposure. At a temperature below 3℃, the harm imposed on the plant was more serious than above 3℃. And, a severe cold-injury would likely to incur if the treatment lasted for 7 days than 3 d or 5 d on the plants. The semi-lethal temperature of a plant increased with prolonged cold exposure. Thus, the cold-injury index should be applied with a consideration of local climatic conditions.
2019, 34(12): 1404-1410.
doi: 10.19303/j.issn.1008-0384.2019.12.007
Abstract:
Objective Effects of a compound microecological bioagent on the weight-gain, gastrointestinal villi and micro-flora in pigs at end of growth period were studied． Methods Three-hundred 60-day-old, weighing 25 kg, fattening pigs were randomly divided into control and treatment groups with 15 replicates of 10 pigs in each group. The treatment pigs were fed the forage diet supplemented with a microecological agent, while control with aseptic water. Daily feed-intake and weight-gain of the individual pigs were recorded for 90 d. Ratio of feed consumption/weight-gain was measured on the 15th, 30th, 60th, and 90th day during the feeding period. At end of the experiment, gastric and colon mucus of 18 randomly selected pigs from each group were collected for the Illumina MiSeq analysis on 16S rRNA gene and the HE-staining on gastrointestinal villi for a microscopic examination. Results The average daily weight-gain of the treatment pigs significantly increased over control (i.e., 35.53 g increase at P＜0.05) with 10 percent reduction on feed-consumption/weight-gain ratio at P＜0.05. The 16S rRNA sequencing showed a significantly higher abundance of Lactobacillus in the gastrointestinal tracts of treatment pigs (averaging 67.81%) than that of control (averaging 13.54%) at P＜0.05, but that of Clostridium difficile (i.e., 4.51%) significantly lower than that of control (i.e., 5.55%) at P＜0.05. In the colon mucus, the genus abundance of Lactobacillus in treatment pigs (i.e., 6.51%) was significantly higher than that in control pigs (i.e., 3.17%) at P＜0.05, but C. difficile (i.e., 2.32%) significantly lower than that of control (i.e., 3.73%) at P＜0.05. The supplementation of the compound microbial agent also significantly increased the length and density of gastrointestinal villi in the treatment pigs (P＜0.05). Conclusion The compound microecological bioagent significantly improved the weight-gain and increased the flora of beneficial bacteria as well as the gastrointestinal villi in the guts on pigs at fattening stage prior to slaughtering.
2019, 34(12): 1411-1418.
doi: 10.19303/j.issn.1008-0384.2019.12.008
Abstract:
Objective Effects of starvation stress and different initial starting forages on the feeding, growth and survival rate of Mastacembelue armatus larvae were studied with a reference to the aquaculture. Method Absorptions on yolk sac and fat globules as well as the point of no return (PNR) of starved larvae were observed by methods of experimental ecology. Eel larvae fed with either freshwater cladocera, nauplius of brine shrimp, egg yolk, crustacean powder or prepared Larvstart-A formulation for 24 d were also under continuous observations． Result The feeding started on the eel larvae at 6-day-old in (27.0±1.5)℃water with an initial feeding rate of 100%. The PNR of starved larvae occurred between 14-d and 15-d of age. Starvation delayed the absorptions on yolk sac and fat globules by the larvae. The consumption on live freshwater cladocera and shrimp nauplius began one day after feeding with 100% feeding rate, and followed by rapid growth with a high survival rate. There was no significant difference on the growth and survival rate between the starved larvae and those fed on the artificial forages such as egg yolk, crustacean powder or Larvstart-A (P＞0.05), which were could not be consumed. Conclusion It appeared that the ideal starting diet for M. armatus larvae would be the freshwater cladocera and brine shrimp nauplius.
2019, 34(12): 1419-1425.
doi: 10.19303/j.issn.1008-0384.2019.12.009
Abstract:
Objective Effects of UDP N-acetylglucosamine pyrophosphorylases (UAP) on the growth and development of Frankliniella occidentalis were studied. Method Based on a transcriptome dataset, an open reading frame (ORF) of UAP gene of F. occidentalis (FoccUAP) was cloned. Expressions of the FoccUAP in different body tissues and growth stages of the insect were detected by RT-qPCR. Effects of UAP gene on the growth and development were examined by microinjecting dsRAN in the 2nd instars (eclosion about 24 h) of F. occidentalis. Result The full-length of FoccUAP ORF was 1 545 bp and encoded 514 amino acids with a predicted molecular mass of 56.738 kDa. FoccUAP contained the conserved domain of glyco-tranf-GTA-type super family, which had a close evolutionary relationship with the orthologues in Isoptera, Blattaria, Orthoptera, and Hemiptera. The RT-qPCR results showed that FoccUAP was highly expressed in the head and abdomen, detected in the antenna, thorax and leg, and found in all developmental stages of the insect. The relative transcript levels of FoccUAP in the 2nd instar, pupa, adult-24 h, adult-48 h, adult-168 h, and adult-240 h were 1.30-, 2.50-, 1.56-, 2.0-, 2.43-, and 2.56-fold, respectively, of those in the 1st instar. Further examination on the RNAi showed that the injection of dsUAP into the 2nd instar F. occidentalis significantly decreased the eclosion rate (36.3%) and the survival rate (5.0% in 120 h after microinjection) as compared to dsGFP controls. Moreover, the dsUAP treatment also induced abnormal phenotypes on wings and abdomen–thorax of the thrips. Conclusion UAP played a significant role in the growth and development of F. occidentalis.
2019, 34(12): 1426-1432.
doi: 10.19303/j.issn.1008-0384.2019.12.010
Abstract:
Objective Real-time continuous monitoring on the invasion of fall armyworms (Spodoptera frugiperda) and the insecticide control efficacy in corn fields in Fujian. Method Based on field surveys, a program was designed to continuously monitor the pest invasion and the efficacies of various insecticides. Selected insecticides were sprayed on the stems and leaves of corn plants in the field for the evaluation. Result Fall armyworm infestation was first reported on corn plants in the province on May 6, 2019. Then it spread to many areas, and by November 4, although only corn crops were affected, the disease had affected 53 counties with a total of 646.23 hectares of corn field. The insecticides, including chlorantraniliprole, indoxair conditioningarb, spinetoram, chlorfenapyr, emamectin benzoate, and lambda-cyhalothrin, were tested in the field and found effective in controlling further spread. After application, these agents displayed an efficacy between 88.08% and 91.46% in 3 d, and between 91.41% and 94.01% in 10 d. Conclusion Fall armyworms damaged the corn crops in the province and could currently be controlled by using insecticides as tested.
2019, 34(12): 1433-1439.
doi: 10.19303/j.issn.1008-0384.2019.12.011
Abstract:
Objective Correlation between the microbial community and the nutrients in rhizosphere soils of varied years of tea-planting was studied to improve soil conditions and productivity at tea plantations. Method Microbial specimens collected from the rhizosphere soils at areas where tea bushes had been planted for 5, 10 and 15 years in Wuyishan city were cultured in the lab using standard dilution-plating method. A correlation analysis was conducted between the microbial count and soil fertility at corresponding sampling spots. Result The microbial population in soil layers decreased with the depth. The counts in different soil layers at areas of different planting ages did not show a consistent pattern. The 10-year-old planting area had the highest microbial count in the rhizosphere. Acidification of the rhizosphere soils was serious showing a pH ranging from 3.14 to 3.36. The fertility indices on soils of different planting ages differed. The contents of total P and total K in the 0−15 cm soil decreased with planting age, while those of total and available N in the 15−30 cm layer increased with years of planting. Other fertility indices either peaked or bottomed out when consecutively cultivated for 5 or 10-years. The redundancy analysis on the data revealed that the bacterial plate count was mainly affected by the contents of available K and total P in soil, while the fungal count by total and available N. Conclusion There was a significant correlation between the microbial population and fertility indices (e.g., available K, available P, total N, and available N ) in the rhizosphere soils of varying years of tea cultivation at the plantations.
2019, 34(12): 1440-1446.
doi: 10.19303/j.issn.1008-0384.2019.12.012
Abstract:
Objective Changes on the form and loss of nitrogen (N) in pig manure due to the addition of biochar during composting were investigated. Method In a forced ventilation reaction box, effects of 0%, 3%, 6%, and 9% addition of biochar (on a dry weight basis) on N in composting pig manure were determined. Result With the biochar addition, the total N and nitrate in the compost increased with time. The total N increased 3.68% to 5.43% by the end of the fermentation process, whereas, the total soluble and ammonium N increased initially and then declined afterward. Increasing biochar mitigated the decline on ammonium N. The rates of N loss by the treatments ranged from 20.69% to 28.18%. At 3% and 6% biochar addition, the ammonia volatilization on the compost were 8.98% and 46.30%, respectively, which were higher than without the addition. On the other hand, 9% of biochar produced the lowest N loss and ammonia volatilization. Conclusion In the pig manure composting, the addition of biochar rapidly heated up the heap and maintained a high temperature for an extended period facilitating the fermentation and conversion of ammonia into nitrate. Increased biochar addition also promoted the nitrate formation. However, the presence of biochar in compost caused greater loss on N as the fermentation progressed.
2019, 34(12): 1457-1462.
doi: 10.19303/j.issn.1008-0384.2019.12.014
Abstract:
Objective Effects of Laminaria japonicapolysaccharides on the proliferation and lipid peroxide production of H2O2-induced vascular smooth muscle cells (VSMCs) were examined in vitro for further understanding on the metabolic mechanism. Method Proliferation of VSMCs was artificially induced by using 50 µmol·L−1 H2O2. Inhibitory rate on the proliferation by the L. japonica polysaccharides were determined by a methyl thiazolyl tetrazolium (MTT) assay. Morphological changes on VSMCs were observed under a microscope. Malondialdehyde (MDA) was employed as an indicator of the lipid peroxide production in VSMCs. Result A significant inhibition effect of the polysaccharides on the H2O2-induced VSMC proliferation with the greatest rate of 73.56% was shown by MTT. Morphologically, the number of VSMCs significantly decreased after an exposure to the polysaccharide. The MDA analysis indicated that the lipid peroxide production by VSMCs significantly declined after the treatment with L. japonica polysaccharides. Conclusion The L. japonica polysaccharides significantly inhibited the proliferation and lipid peroxide production in the H2O2-induced VSMCs.
2019, 34(12): 1463-1470.
doi: 10.19303/j.issn.1008-0384.2019.12.0015
Abstract:
Mycoplasma ovipneumoniae (Mo) is one of the main pathogens that causes mycoplasmal pneumonia in sheep and goats. The worldwide disease brings great economic loss to the industry. Currently, 3 detecting methods are commonly used for the disease. One applies the pathogen isolation and identification, but the isolation rates tend to be low. The second is the most popular molecular biology method. It employs PCR, LAMP, rapid touchdown PCR-lateral flow assay, or DNA probe technology for the diagnosis. The third one is the immunological detection by indirect hemagglutination, ELISA, immunohistochemistry or indirect immunofluorescence. The disease control largely relies on the vaccination and drug treatment. At present, inactivated vaccines are available, and various genetically engineered vaccines are being developed. The drug treatments of the infection include the uses of antibiotics, traditional Chinese medicine, and combination of traditional Chinese and western medicines. In recent years, the immune defense molecules were reported to show immunomodulatory and therapeutic effects on mycoplasmal pneumonia in sheep and goats. It is postulated to be a new approach for treating the disease. This article reviews the epidemiology, diagnosis, treatments, and research on vaccines of Mo infection.
Mycoplasma ovipneumoniae (Mo) is one of the main pathogens that causes mycoplasmal pneumonia in sheep and goats. The worldwide disease brings great economic loss to the industry. Currently, 3 detecting methods are commonly used for the disease. One applies the pathogen isolation and identification, but the isolation rates tend to be low. The second is the most popular molecular biology method. It employs PCR, LAMP, rapid touchdown PCR-lateral flow assay, or DNA probe technology for the diagnosis. The third one is the immunological detection by indirect hemagglutination, ELISA, immunohistochemistry or indirect immunofluorescence. The disease control largely relies on the vaccination and drug treatment. At present, inactivated vaccines are available, and various genetically engineered vaccines are being developed. The drug treatments of the infection include the uses of antibiotics, traditional Chinese medicine, and combination of traditional Chinese and western medicines. In recent years, the immune defense molecules were reported to show immunomodulatory and therapeutic effects on mycoplasmal pneumonia in sheep and goats. It is postulated to be a new approach for treating the disease. This article reviews the epidemiology, diagnosis, treatments, and research on vaccines of Mo infection.
