2021 Vol. 36, No. 5
Display Method:
2021, 36(5): 501-505.
doi: 10.19303/j.issn.1008-0384.2021.05.001
Abstract:
Objective A duplex PCR assay for rapid detecting Pasteurella multocida serogroup F strain in rabbits was developed. Methods Primer concentration and annealing temperature for the duplex PCR were optimized based upon two sets of specific primers targeting the conserved sequences of kmt1 of P. multocida and fcbD of P. multocida serogroup F strain. Specificity, sensitivity, and accuracy of the methodology were tested for its applicability. Results The optimized conditions for the assay included 0.8 μmol·L−1 on the primer concentration and 60 ℃ for the annealing temperature. The assay detection was specific for P. multocida serogroup A, D, and F strains and free of cross-reactions with Bordetella bronchiseptica, Klebsiella pneumonia, Escherichia coli, Staphylococcus aureus, and negative control. A highly sensitive detection limit up to 1×103 copies·μL−1 on genomic DNA of P. multocida serogroup F isolate was achieved. In the repeated intra- and inter-assays on 90 lung specimens from dead diseased rabbits, the assay variation coefficients were identical. By using 87 lung samples collected from known infection cases, the newly developed duplex PCR assay and reported multiplex PCR assay yield agreements of 97.70% and 94.25% with the known results, respectively. Moreover, the current duplex PCR determination also yielded an agreement of 93.10% on the measurements with the reported from a multiplex PCR assay. Conclusion The newly established duplex PCR assay based on the specific primers targeting the conserved sequences of kmt1 of P. multocida as well as fcbD of P. multocida serogroup F strain was tested to be highly specific, sensitive, repeatable, and accurate in detecting the pathogenic P. multocida serogroup F strain in rabbits.
2021, 36(5): 506-511.
doi: 10.19303/j.issn.1008-0384.2021.05.002
Abstract:
Objective In order to explore the current morbidity and epidemic trend of three kinds of common viral immunosuppressive diseases in chicken flocks in southeast Guangxi. Method From March 2018 to April 2019, a total of 637 sick chicken sera were collected from scattering chicken raising households in nine counties and cities including Yulin, Beiliu, Xingye, Bobai, Rongxian, Luchuan, Guigang, Guiping and Pingnan, to detect the serum antibodies against three viruses by an enzyme-linked immunosorbent assay (ELISA) and analyzed the impact of different factors including region, season, breed and age on the infection statuses of these three viral immunosuppressive diseases. Result The results showed that the antibodies against three common immunosuppressive viruses were ubiquitous in the above areas and the positive rates of antibodies against different viruses were affected by regions, seasons, breeds and age groups of the chicken flocks. The positive rates of antibodies against Chicken infectious anemia virus (CIAV), Reticuloendotheliosis virus (REV) and Avian reovirus (ARV) were 23.86%, 13.97% and 7.06% respectively, indicating that the positive rate of CIAV were higher than other two viral immunosuppressive diseases in chicken flocks of the farmers in the above-mentioned regions and it should be regarded as the focus of the prevention and control of epidemic diseases in chicken flocks. In addition, multi-infection was the common infection type, as the mixed infection rate reached up to 24.65%, and CIAV co-infection with other pathogens were the most common diversified infection type, accounting for 98.11%. Conclusion This study provided the serological surveillance of chicken viral immunosuppressive diseases in the chicken flocks of the scattering raising households in the region of southeast Guangxi and provided a reliable reference for making control measures of these three kinds of common viral immunosuppressive diseases.
2021, 36(5): 512-517.
doi: 10.19303/j.issn.1008-0384.2021.05.003
Abstract:
Objective To elucidate the regulatory function and mechanism of the pathogenic processes mediated by the rice stripe virus (RSV)-encoding NSvc4 protein in rice, the high titer concentrated polyclonal antibody containing the chloroplast-related chaperonin-60-beta (CPN60-β) protein against the RSV disease was prepared. Method The CPN60-β fragment was amplified by RT-PCR from rice genome. The recombinant plasmid pET-CPN60-β was constructed with prokaryotic expression plasmid pET-28a (+) and further expressed in Escherichia coli BL21 cells. The CPN60-β fusion protein was purified and immunized into New Zealand rabbits to obtain polyclonal antibody. Titer and concentration of the polyclonal antibody against CPN60-β protein were detected by ELISA and SDS-PAGE for confirmation. Result The approximately 657bp chloroplast-related CPN60-β fragment was successfully amplified by RT-PCR. The reconstructed plasmid pET-CPN60-β positively expressed the CPN60-β fusion protein in E. coli BL21 cells under IPTG concentration of 0.5mmol·L−1 at 37 ℃ with a rotate speed of 220 r·min−1 and an induction time of 5 h. The purified polyclonal antibody had a high titer of 1:106 and a concentration of 300 μg·mL−1 as detected separately by ELISA and SDS-PAGE. Conclusion The conditions of CPN60-β prokaryotic expression were confirmed and the polyclonal antibody against chloroplast-related CPN60-β protein with high titer and concentration successfully prepared for further studies.
2021, 36(5): 518-525.
doi: 10.19303/j.issn.1008-0384.2021.05.004
Abstract:
Objective Effects of waterlogging, a major abiotic stress ill-affecting the wheat production in the middle and lower reaches of the Yangtze River, at booting stage on the physiology and yield of wheat were studied. Method The growth and yield of Yangmai 16 and Zhongmai 895 wheat plants subjected to flooding at booting stage by controlled water supply in pots were analyzed. Result (1) Waterlogging significantly reduced the chlorophyll content in wheat leaves. The longer the stress lasted, the greater the decline on SPAD and the more severe the injury, the greater SPAD reduction on the leaves. More serious damage was observed on the top second leaf than on the top first flag leaf of a plant. (2) The activities of antioxidant enzymes, such as CAT, SOD, and POD, changed in an inverted V pattern as the waterlogging prolonged. The content of reactive oxygen species (ROS) either decreased or increased slowly in the early stage of waterlogging but increased sharply in the late stage. (3) At booting stage, the wheat plants might respond to the waterlogging stress to increased slightly on the effective number of ears per plant, grain number per ear, 1000-grain weight, and other yield factors. (4) Waterlogging at wheat heading stage exerted no significant effect on the plant height. On the other hand, lasting waterlogging significantly decreased the grain yield with declined effective panicle number, grain number per panicle, and 1000-grain weight. After 15 d of continued flooding, the yields per plant of Zhongmai 895 and Yangmai 16 decreased by 51.47% and 43.99%, respectively, over CK. Conclusion Waterlogging imposed on wheat plants at booting stage significantly reduced the leaf chlorophyll content, disrupted the oxygen metabolism, and upset the delicate balance of the antioxidant enzyme system. As a result, the excessively accumulated ROS in the plant could induce the peroxidization of lipid cellular membrane and impair the cell structure and functions that was detrimental to the photosynthesis as well as the nutrient transfer and accumulation of the plant. In the end, the much-reduced biomass and grain-filling but significantly increased number of empty, deflated, and unusable grains meant a final crop reduction. Insofar as resistance to waterlogging stress is concerned, Yangmai 16 was found to be stronger than Zhongmai 895.
2021, 36(5): 526-531.
doi: 10.19303/j.issn.1008-0384.2021.05.005
Abstract:
Objective A new disease-resistant, high-yield peanut variety was bred to meet the urgent demand of the industry in Guangxi province. Method After years of directional selection from F1 to F9 using the F4 of Yueyou 45×Guihua 17 as female parent and Guangdong Shanyou 188 as male parent for the crossing, Guihua 202 was obtained and submitted to the Joint Test on New Peanut Varieties in Guangxi from 2014 to 2017. Result At the 2014 to 2015 field trials, Guihua 202 displayed an average pod yield of 4 039.07 kg·hm−2, which was 6.69% higher than that of the reference Guihua 21, showing an initial indication of yield improvement. In the subsequent 2016 to 2017 trials, it delivered the average pod and peanut yield of 4 281.30 kg·hm−2 and 2 746.73 kg·hm−2, respectively, representing a significant increase on pod yield of 208.875 kg·hm−2 or 5.13% and a not significant decrease on peanut yield of 120.225 kg·hm−2 or − 4.19% over Guihua 21. Guihua 202 peanuts had an average of 50.64% on crude fat that included 45.1% of oleic acid and 33.6% of linoleic acid with an oleic/linoleic acid ratio of 1.34, and that of 27% on protein. The new variety grew vigorously with a compact plant type characterized by 45.9 cm main stem height, 52 cm branch length, 7.9 branches, 15.4 pods per plant, 590 pods per kg, 207.2 g on 100-pod weight, 77.7 g on 100-seed weight, and 64% on kernel rate. This disease-resistant and high-yield new peanut variety has passed the national non-major crop variety registration in September 2020. Conclusion Guihua 202 exhibited desirable qualities and was considered appropriate for cultivation in Guangxi. However, it required ample water supply and fertilization to fully deliver its high yield potential.
2021, 36(5): 532-541.
doi: 10.19303/j.issn.1008-0384.2021.05.006
Abstract:
Objective Physiological characteristics of Adonis amurensis in response to varying degrees of drought stress and subsequent rewatering were studied prior to the introduction for commercial cultivation and applications of the cultivar. Method Potting with controlled watering was applied to study the effects of varied drought stress and subsequent rewatering on the physiological characteristics of A. amurensis. Result The depleting water supply to the A. amurensis plants decreased the biomass, plant height, relative moisture content in leaf, total chlorophyll, and soluble protein, increased the contents of soluble sugar and malondialdehyde as well as the relative electrical conductivity of the leaves, and rose but followed by a decline on the contents of proline, peroxidase, and superoxide dismutase activities of the plants. Meanwhile, the indicators such as Pn, Gs, Tr, and Ci decreased, Fm, Fv/Fo, Fv/Fm, qP, ETR, and ФPSⅡ Conclusion A. amurensis plants seemed to be capable of withstanding continuous water depletion up to 8 d and maintaining normal growth with a minimum 29.9% of soil relative moisture content. After the threshold points, prolonged drought stress with less than the minimum water requirement in the soil would irreversibly damage the plant physiology.Therefore, water supplement for A. amurensis should not exceed 8 days under drought condition.
2021, 36(5): 542-548.
doi: 10.19303/j.issn.1008-0384.2021.05.007
Abstract:
Objective Microstructures and polysaccharide contents in the wild Dendrobium officinalein in Danxia landform areas and artificially propagated seedlings were compared for product differentiation and cultivation of the valuable herbal medicinal material. Methods At areas of Danxia landform, stems from wild and 2-3 year old cultivated D. officinalein plants were collected for microscopic morphological examination as well as histochemical and chemical analyses. Results The reddish-purple stems of the wild D. officinalein plants bore dark greenish-purple leaves with no visible internodes. In contrast, the artificially propagated seedlings had light green leaves on dark green stems with internodes. In addition, the plant height, stem diameter, and internode distance of the cultured seedlings were greater than those of the plants found in the wild. There were also significant differences between them in the cuticle thickness, epidermal cell diameter, subcutaneous cell diameter and layer number, sheath fiber diameter and number, vascular bundle diameter and number, xylem and phloem thickness, calcium oxalate needle length, catheter diameter, wood parenchyma cell diameter, and sheath cell wall thickness of the plants. A large amount of polysaccharide granules existed in aggregation in the tissues of the cultivated seedlings which turned its deep reddish purple color by staining darker than those in the wild D. officinalein. The granules differed in size as well. However, the wild D. officinalein had a higher content of polysaccharides than the propagated seedlings. Conclusion With respect to the microstructure and metabolites of the stems, there were significant differences between the D. officinalein in the wild and the cultivated seedlings. The morphology, microstructure, histochemical localization, and polysaccharide content of the medicinal material could be adequate indicators in identifying, evaluating, and differentiating the products of different origins.
2021, 36(5): 549-555.
doi: 10.19303/j.issn.1008-0384.2021.05.008
Abstract:
Objective The open reading frame and gDNA of the gene associated with the chalcone synthase (CHS), the first key enzyme in the flavonoid biosynthetic pathway in Moringa oleifera, were cloned for a bioinformatic analysis. Method Primers were designed according to the M. oleifera genome in NCBI database. The leaf cDNA and genomic DNA were used as templates to amplify the MoCHS1 with PCR for a subsequent bioinformatic analysis. DNAMAN 9.0 and MEGA 10.0 were used for the multiple sequence alignment and phylogenetic tree construction. Result The ORF of MoCHS1 Conclusion MoCHS1
2021, 36(5): 556-563.
doi: 10.19303/j.issn.1008-0384.2021.05.009
Abstract:
Objective Endophytic bacteria that could effectively control the copper blight, one of the most significant diseases that seriously infects the seedlings and saplings, of Chinese fir (Cunninghamia lanceolate) were investigated. Methods Candidate endophytic bacteria were cultured and isolated from leaves of Chinese fir followed by morphological, physiological, and biochemical analyses as well as 16S rRNA sequencing for identification. Pathogen inhibition against Pestalotiopsis apiculatus by the sterile fermentation filtrate of potential specimens was tested on toxic plate and Oxford cup and observed under a microscope. Effectiveness of the disease control by the selected bacteria was further verified in vitro on fir leaves. Results The endophytic bacterium coded SM-1 showed a significant antagonistic effect against P. apiculatus. It was isolated and identified as Bacillus atrophaeus. On the toxic plate and Oxford cup tests, the SM-1 fermentation filtrate yielded a P. apiculatus inhibition rate of 58.80%. Morphologically, the bacterium inhibited the mycelial growth and caused cellular swelling that changed the cells spherical in appearance of the pathogen. The efficacy of the SM-1 filtrate on copper blight on the fir leaves was 95% with significantly reduced disease severity (P＜0.01). Conclusion The SM-1, identified as B. atrophaeus, appeared to be a potential biocontrol agent to deter copper blight on Chinese fir.
Efficacies of Nine Seed Coating Agents for Disease Control and Safety for Fresh Consumption of Maize
2021, 36(5): 564-571.
doi: 10.19303/j.issn.1008-0384.2021.05.010
Abstract:
Objective Efficacies of 9 seed coating agents in controlling the major diseases and pest infestation as well as their application safety for fresh consumption of maize were investigated. Method Nine commercially available seed coating agents (5 were insecticides, and 4 insecticide/fungicide mixtures) were applied on maize to determine their effects on the seed emergence and survival rates, the control on fall armyworm (Spodoptera frugiperda) infestation at seedling stage and top/stalk rot disease on the plants, and the crop yield in a field experimentation. Result Other than Haoniandong (a 35.00% carbosulfan WS), none of the 9 agents showed a negative effect on seed emergence or survival rate. The control efficacies of Lumingwei (a 50.00% chlorantraniliprole FS) at 5 g·kg−1 and IPP1 at 25 g·kg−1 on fall armyworm infestation on the maize at seedling stage were 64.15% and 59.40%, respectively. Dingmiaoxin (a mixture of 50.00% chlorantraniliprole FS and 4.23% ipconazole·metalaxy ME) at 5+5 g·kg−1 reduced the top/stalk rot infection rate to 56.07%. On the yield of the plants grown from the treated seeds, the application of Manshijin (a mixture of 50.00% chlorantraniliprole FS and 35g·L−1 metalaxyl-m·fludioxonil FSC) at 5+2 g·kg−1, the mixture of Lumingwei and Kuaimiao at 5+2 g·kg−1 and Dingmiaoxin at 5+5 g·kg−1 increased the grain yields by 5.92%, 2.05% and 6.24%, respectively, and the fresh ear yields by 3.17%, 5.58%, and 3.55%, respectively, over control. Conclusion Among the tested seed coating agents, Dingmiaoxin at the recommended dosage showed a significant efficacy in controlling the major diseases and pest infestation as well as improved crop yield without growth impairment on the maize. It could be applied on maize for fresh consumption cultivated in Fujian.
2021, 36(5): 572-577.
doi: 10.19303/j.issn.1008-0384.2021.05.011
Abstract:
Objective The effect of temperature on life table parameters of Ectropis grisescens were measured. Method In this study, five temperatures (19 ℃, 22 ℃, 25 ℃, 28 ℃ and 31 ℃) treatments were set up to analysis the life table parameters of E.grisescens. Result The results showed that temperature can affect the growth and development of E. grisescens, and the developmental period from egg to adult decreased as temperature increasing, the shortest developmental period (27.6 d) of E. grisescenswas observed at 31 ℃. Different temperature had significant effect on survival rate of E. grisescens, the higher survival rate (64.0%) of E. grisescens was found at 22 ℃ compared with other temperature treatments. Temperature had a significant effect on the life table parameters of E. grisescens population. Significantly, higher net reproductive rate (R0) of E. grisescens population was found at 25 ℃ compare with other temperature treatments and R0 was up to 90.88 offsprings per individual. The intrinsic rate of increase (r) and the finite rate of increase (λ) were also the highest at 25 ℃, which was 0.126 d−1 and 1.134 d−1, respectively. Conclusion The results of this study indicated that 25 ℃ was the optimum temperature for the population growth of E. grisescens, which provided a scientific basis for indoor rearing, field population occurrence prediction and integrated control of this insect pest.
2021, 36(5): 578-584.
doi: 10.19303/j.issn.1008-0384.2021.05.012
Abstract:
Objective The occurrence and damage of Chreonoma atritarsis are closely related to its ecological environment factors. The ecological characteristics and spatial distribution of C. atritarsis larvae are the basis for estimating the population density and pest prediction, which can provide theoretical basis for pest ecological control. Method Based on the systematic investigation on the damage of C. atritarsis larvae in the main Camellia oleifera bases in Jiangxi Province, the spatial pattern of C. atritarsis larvae was studied by using six aggregation indexes and two regression models. The relationship between the occurrence of C. atritarsis larvae and ecological factors was analyzed by using SPSS statistical software. Result The results showed that the spatial distribution pattern of the larva population was uniform, and the individuals in the population were mutually exclusive. Forest canopy density and understory vegetation coverage are the two key factors affecting the pest population rate of C. oleifera. The relationship between forest canopy density and pest population rate is extremely significant negative correlation, while understory vegetation coverage and pest population rate are extremely significant positive correlation. Understory vegetation coverage, forest canopy density, forest edge, tree height and tree age were the key factors for risk assessment of C. atritarsis. At the same time, slope aspect and slope position also had different effects on the percentage of infected plants. The distribution of C. atritarsis. larvae on the branches of C. oleifera was highly selective. They preferred to choose the branches with the age of 3-6 a, diameter of 1.5-2.2 cm, angle less than 60°, and height within 40-59 cm. Conclusion The results of this study enriched the research content of spatial distribution of C. atritarsis, and showed that the spatial pattern of uniform distribution of C. atritarsis larvae was the result of the joint action of biological, ecological and environmental factors. The key forest factors affecting the occurrence and damage of C. atritarsis larvae and their distribution on branches were explored, which had practical value for guiding prediction and biological control.
2021, 36(5): 585-594.
doi: 10.19303/j.issn.1008-0384.2021.05.013
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Objective The pathogenicity and avirulent genotypes of Magnaporthe oryzae found in Fujian in recent years were analyzed to define their existence and year-to-year changes in different regions. Method For the study, 179 strains of rice ear neck blast were collected from 9 major rice-producing areas in the province from 2018 to 2020 and isolated to identify the near-isogenic lines (NILs) that contained only one resistance gene. Result Among the 179 rice blast strains, the proportion of strong, slightly strong, medium, and weak pathogenic classes were 26.81%, 36.31%, 27.37%, and 9.51%, respectively. Among the 4 high resistance genes, Pi-z5 and Pi-9(t) showed the greatest resistance frequencies of 91.49% and 91.25%, respectively, followed by Pi-kh and Pi-1 of more than 80%. During the sampling years, the 9 avirulent genes produced more than 20% on frequency decline were Avr-kh, Avr-7(t), Avr-5(t), Avr-3, Avr-kp, Avr-19(t), Avr-km, Avr-z, and Avr-ks. In the 23 types of avirulent genes, the pathogens with 6, 7, 8, 9, and 11 gene combinations had the highest appearance frequencies of 10.06%, 8.94%, 8.94%, 7.82%, and 8.38%, respectively. A total of 24 avirulent genes were identified in the rice blast strains found in the 9 regions that showed the highest frequencies of appearance at 49.19% in Shanghang, 48.18% in Guangze, and 41.23% in Wuyishan. Conclusion Most rice blast strains in Fujian were strongly pathogenic to the 24 resistance genes, as discovered by this study. Among all, Pi-z5, Pi-9(t), Pi-kh, and Pi-1 had the greatest frequencies of resistance, Avr-z5 and Avr-9(t) the most consistent over the years, and Avr-ks, Avr-b, and Avr-ta the lowest with a frequency less than 20%. The corresponding avirulent genes could be useful for breeding, but the selection must be done with due caution.
2021, 36(5): 595-601.
doi: 10.19303/j.issn.1008-0384.2021.05.014
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Objective By analyzing the relation between changed thermal conductivity under varied moisture content and plough layer temperature of soil in a confined chamber and the incidence rate of verticillium wilt on eggplants grown on the soil, the mechanism and disinfecting effect of utilizing a high-temperature stuffy enclosure to mitigate the disease were studied. Method The transient plane source (TPS) technique was applied to measure the thermal conductivity of the chamber soil with different moisture content（0%、5%、10%、15%、20%、25%和30%） in the laboratory. Take 6 treatments（A1; B1; A2; B2; CK1; CK2）with 2 levels（5.06%和23.48%）of water content as the target, and measure the soil temperature at depths of 5, 10, 15, 20, 25,and 30 cm of each treatment, and statistics the incidence of eggplant Verticillium wilt in 6 treatments. Result Between 5% and 25%, high moisture content significantly raised the thermal conductivity of the soil,the relationship between them is nearly linear. Under same conditions, the high-temperature stuffy enclosure effectively elevated the temperatures of the soil layers throughout, and with the increase of soil water content, the corresponding soil layer temperature increased, and plastic film mulching can also increase the plough layer temperature. Under the same soil moisture content, the treatment of high-temperature stuffy enclosure with plastic film mulching, the incidence rate of Verticillium Wilt of eggplant is lower and the control effect is better. Conclusion It appeared that, by increasing the moisture content in soil, solar energy could be arrested more effectively throughout the soil due to the increased thermal conductivity. And the higher the soil temperature became, the greater the disinfection effect, which would result in reduced verticillium wilt on the eggplants grown in the high-temperature stuffy chamber.
2021, 36(5): 602-609.
doi: 10.19303/j.issn.1008-0384.2021.05.015
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Objective Effects of intercropping green manures with tea plants on the chemistry and bacterial community of plantation soil were analyzed for ecological improvements. Methods Changes on the soil pH, heavy metals, and bacterial diversity and community were monitored after various intercropping treatments. Results The Lupinus perennis (L)-Brassica campestris (B)-Chamaecrista rotundifolia (C) intercropping with tea plants did not improve but, in fact, lowered the soil pH. However, significant acidity mitigation was achieved by BC- or LB-intercropping with tea plants in the pot experiments. LB-intercropping also significantly reduced the content of heavy metals including Cd and Hg. The bacterial diversity and community structure of the intercropped soil were significantly changed with Proteobacteria becoming the most abundant phylum and Actinobacteria decreasing to less than 20% of the total population in the treatments with L, LB, or LBC. The intercropping also significantly increased Cyanobacteria population to more than 1%, in comparison to 0.1%-0.3% on control. Conclusion Intercropping L. perennis and B. campestris with tea bushes was conceivably to enable improvements on pH, Cd/Hg contents, and microbial community of the soil at plantations.
2021, 36(5): 610-618.
doi: 10.19303/j.issn.1008-0384.2021.05.016
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Objective An optimized low-cost medium for high-density culture of Saccharomyces cerevisiae was formulated. Method S. cerevisiae JH301 was cultured on the basic molasses media of varied compositions to determine the optimal carbon source, nitrogen source, inorganic salt, and natural growth promoters for the yeast preparation in a single factor test. Optimization models using different statistical analyses were compared for the formulation finalization. Result From a U16(88) uniform experiment, the optimized medium formulation was determined to apply the carbon source that included glucose, cottonseed sugar, and trehalose, tryptone for the nitrogen source, K2HPO4 as the inorganic salt, and the natural growth promoters that consisted of distiller's grains polypeptide, rice saccharification solution, and soybean polysaccharide. The finalized formula called for 23.72 g·L−1 distiller's grains polypeptide, 44.15 g·L−1 rice saccharification solution, 31.88 g·L−1 soybean polysaccharide, 22.45 g·L−1 cottonseed sugar, 13.97 g·L−1 glucose, 15.00 g·L−1 trehalose, 27.25 g·L−1 tryptone, and 3.00 g·L−1 K2HPO4, in addition to 10% soluble solids molasses. The resulting yeast biomass reached 1.48×108 cfu·mL−1, which was one order of magnitude higher than the culture obtained from the basic molasses medium. Conclusion Rich in small molecular polypeptides capable of promoting the cell proliferation of S. cerevisiae, the natural distiller's grains polypeptide was formulated in the medium to yield a low-cost preparation for the yeast.
