2021 Vol. 36, No. 7
Display Method:
2021, 36(7): 735-741.
doi: 10.19303/j.issn.1008-0384.2021.07.001
Abstract:
Objective Effects of planting density applied by the mechanical transplantation of pot seedlings on grain formation and yield of hybrid indica rice with different panicle types were studied. Method A field experiment was carried out with 4 planting densities (i.e., D1 at 33 cm×12 cm, D2 at 33 cm×14 cm, D3 at 33 cm×16 cm, and D4 at 33 cm×18 cm) by mechanical seedling transplantation. Seedlings of two indica rice cultivars with different panicle types, i.e., the large panicle type Chaoyou 1000 and the medium panicle type Huiliangyou 630, were planted. Tiller growth and photosynthetic matter generation as well as the grain yield and yield traits of the rice plants were monitored for analysis. Result (1) The number of stems and tillers at critical growth periods of the rice plants declined as the seedling density decreased. The productive tillers decreased significantly for the large panicle type cultivars but relative stable for the medium panicle type. (2) The leaf area index at key growth stages and the rate of change declined with decreasing planting density resulting in an increased spikelet per unit leaf area. (3) Reduced seedling density raised the grain yield initially followed by a decline. (4) Under D2 or D3, both cultivars showed better overall quality and grain yield with larger spikelets per unit leaf area, lower decreasing rate of leaf area, and the highest dry matter accumulation at late growth stage than the other treatments. (5) Varied planting density affected grain yield basically due to the altered number of effective panicles and spikelets per panicle of the rice plants. And (6) Lower seedling density significantly reduced the number of panicles but increased the spikelets per panicle. However, no significant differences on the 1000-grain weight were observed among the treatments. Conclusion In applying mechanical means for pot seedlings transplantation, it would be advisable to properly reduce the density of the hybrid large panicles indica rice seedlings to increase the spikelets per panicle by allowing formation of ample panicles to maximize the grain yield. For the medium panicle type rice, on the other hand, combination of increasing panicles and spikelets per panicle by altering the planting density seemed necessary to achieve the full yield potential.
2021, 36(7): 742-749.
doi: 10.19303/j.issn.1008-0384.2021.07.002
Abstract:
Objective In preparation of breeding new early-mature, cold tolerant, high yield winter-potato varieties the nutritional quality of the hybrid candidates was evaluated. Method A randomized block experiment was conducted in the field to compare the contents of vitamin C, reducing sugar, dry matters, protein, mineral elements, and amino acids in 27 hybrid progenies of a cold tolerant, high yield, high quality Minshu 2 as the female parent and a very early-mature, high quality Zhonglongshu 1 as the male parent. Result Significant variations on contents of the nutrients were found among the 27 cultivars. The coefficient of variations (CV) on vitamin C and reducing sugar were 22.4% and 18.3%, respectively, and smaller CV on dry matters and protein 10.8% and 14.9%, respectively. On minerals, the greatest differentiations were shown on Mg and Fe contents with CVs at 17.0% on Mg and 24.2% on Fe, but lower at 10.2% on K, and 12.1% on Zn. The contents of 17 amino acids varied in the CV range from 12.9% to 38.0% with Asp, Glu, Cys, Agr, and Pro higher than 25%, and the total amino acids at 14.6%. It appeared that these progenies were highly diverse genetically resulting in significant variations on their nutritional quality. Hence, careful selection of the hybrids would be necessary to maximize the nutritional quality of the new breed. Using the principal component and cluster analyses, 12 high-quality candidates including 1320040, 1320001, and 1320009 were preliminarily selected. Conclusion The nutritional quality of the 27 hybrids with rich genetic diversity was compared. Accordingly, 12 were chosen as candidates for breeding experimentation.
2021, 36(7): 750-758.
doi: 10.19303/j.issn.1008-0384.2021.07.003
Abstract:
Objective Molecular mechanisms of Citrus grandis (L.) Osbeck. cv. Guanximiyou in response to simulated acid rain stress were investigated. Method The llumina HiSeq 4000 system, a high-throughput transcriptome sequencing technology, was applied to reveal the differential expressions of the grapefruit transcriptome after a 24 h simulated acid rain treatment. The unigenes obtained were compared to the Nr and KEGG database. Abundance of gene expression of the samples were screened according to transcriptome data by using PRKM method. Differentially expressed genes (DEGs) among the treated samples were estimated by referring to the standard of FDR ≤ 0.05 and |log2FC| ≥ 1. Functions and pathways of those DEGs were analyzed using the Gene Ontology (GO) and KEGG pathway database. Result Significant lumpy lesions began to appear on the young grapefruit leaves 24 h after the artificial acid rain spray with 21 497 fully described unigenes obtained. In comparison to control, 879 of the genes were significantly upregulated and 588 downregulated. The top 50 DEGs were all in the upregulated category and mainly associated with metabolic pathways, secondary metabolism, phenylpropyl propane biosynthesis, or terpenoid biosynthesis. The GO enrichment analysis showed the DEGs being largely located in extracellular region and, among various molecular functions, the catalytic activity being the most significantly enriched, followed by oxidoreductase activity, while the DNA metabolism being the most significant of DEGs in the GO term on biological process. The KEGG enrichment analysis indicated that DNA replication was the most significant enrichment pathway, followed by secondary metabolic biosynthesis, and lignin synthesis. The PCR fluorescence quantitative analysis on the 4 DEGs in the secondary metabolic biosynthesis pathway [i.e., POD isozyme cg3g018770 and cg2g001440, cinnamyl coenzyme A reductase (CCR) isozyme cg1g021310, and 4-coumaric acid-coenzyme A ligase (4CL) isozyme cg3g029290] confirmed that the acid rain stress indeed significantly affected the expressions of these genes. Conclusion C. grandis (L.) Osbeck. cv. Guanximiyou was strongly tolerant to acid rain. The stress response of the plants involved numerous genes regulated by various collaborative biological processes. Among them, the regulation of secondary metabolism appeared to play a major role in coping with acid rain stress by the plant.
2021, 36(7): 759-765.
doi: 10.19303/j.issn.1008-0384.2021.07.004
Abstract:
Objective ISSR-PCR reaction system for genetic study on Phyllanthus emblica germplasms was optimized. Methods A mixed DNA template composed of genomic DNA of P. emblica germplasms came from Myanmar, India, Guangdong, Yunnan, and Fujian was obtained. The single factor test and response surface analysis were used to optimize the ISSR-PCR reaction conditions including primer concentration, amount of 2×Taq Master Mix, DNA template amount, and annealing temperature. Result The primer concentration and addition amount of 2×Taq Master Mix had a greater impact on the amplification than did the DNA template amount. A significant interaction between the primer concentration and DNA template amount was found. The optimized system with a primer concentration of 0.4 μmol·L−1, a 2×Taq Master Mix of 13 μL, and a DNA template concentration of 30 ng was established that achieved a low relative error of 9.39% in predicting the theoretical response. Within the annealing temperature between 50.5 ℃ and 52.7 ℃, increasing temperature improved the number and quality of bands. When the annealing temperature is 50.5-52.7 ℃, the number of strips increases, and the quality of the strips becomes better with the increase of temperature. The annealing temperature is 52.7 ℃ to obtain good diversity and clear bands. Conclusion The optimized ISSR-PCR reaction system was established applying a primer concentration of 0.4 μmol·L−1, a 2×Taq Master Mix of 13 L, a DNA template concentration of 30 ng at the annealing temperature of 52.7 ℃ for 35 amplification cycles. The methodology could be used to study the genetic diversity and relationship of P. emblica germplasms.
2021, 36(7): 766-770.
doi: 10.19303/j.issn.1008-0384.2021.07.005
Abstract:
Objective Two varieties closely related to Lactarius delicious found in the wild in Guizhou were morphologically and molecularly identified and homology analyzed. Method Two species of Lactarius from a Pinus massoniana forest in Hejiang Village, Meitan County were examined on their morphological features under a microscope and on their phylogenetic characteristics by ITS rDNA sequence. Result The two mushroom varieties were identified to be L. vividus and L. hatsudake. Between them, significant discrepancies in morphology and ITS phylogeny were evident. L. vividus was 95% homologous with L. deliciosus, while L. hatsudake slightly lower at 93%. Conclusion The information provided a concrete basis for the species identification facilitating the conservation, domestication, research, and utilization of the rare and valuable Lactarius in the wild.
2021, 36(7): 771-778.
doi: 10.19303/j.issn.1008-0384.2021.07.006
Abstract:
Objective Morphological and genetic characteristics of strains of Auricularia cornea were studied to facilitate new variety breeding and germplasm conservation. Method The agronomic properties and ISSR molecular markers of 8 major strains of cultivated or hybrid A. cornea collected from Fujian and other producing provinces in China were determined for comparison. Result The strains had significant morphological and genetic differences. Zhanger 43-28 and Strain 43012 showed the highest rate of mycelial growth with an average diameter of 11.8 cm and 11.3 cm, respectively, a thickness of 0.128 cm and 0.126 cm, respectively, and an output of 72.5 g·bag−1 and 71.5 g·bag−1, respectively, on earpieces. Za 10 had numerous earpieces with the fruiting body a chrysanthemum-like appearance. And the ventral surface of Strain CR5 was light reddish brown in color. The dried fruiting bodies of the 8 strains were either white or yellow on the back. Thus, Yonger 13, Strain 781, and Zhangping 42 were commercially categorized as yellow-backed and the other strains white-backed A. cornea. At 75% similarity on ISSR molecular markers, the 8 strains were clustered into Group 1 that consisted of Strain 781 and Yonger 13, the similarity of the two strains was 98%. Group 2 of Strain CR5, Group 3 of Zhanger 43-28 and Za 10, the similarity of the two strains was 76%. Group 4 of Sumao 3 and Strain 43012, the similarity of the two strains was 83% and Group 5 of Zhangping 42, Zhangping 42 and the remainders at 53%. Conclusion Combined the agronomic characteristics and ISSR clustering result, Yonger 13 and Strain 781 appeared phylogenetically closely related. They were same species but had been given different names. Strains Za 10, CR5, 43012 and Zhanger 4328 have their own advantages and can be used as parents of cross breeding.
2021, 36(7): 779-784.
doi: 10.19303/j.issn.1008-0384.2021.07.007
Abstract:
Objective A rapid, sensitive detection method for early diagnosis and epidemiological survey on enzootic nasal tumor (ENT) in goats was established. Method Bioinformatics methods were employed for sequence alignment of ENTV-2 with ENTV-1, ERVs, and JSRV in search for the conserved sequence of the virus. Primers for qPCR were designed to establish a SYBR-Green I RT-qPCR methodology for its detection. Reaction conditions were optimized, and a standard positive plasmid used to determine the specificity, sensitivity, and reproducibility of the newly developed assay. Result A linear standard curve was found for the detection with a R2=0.992. The method specifically detected only ENTV-2, not the highly homologous ERVs, nor amplified ORFV, MO, or Mmc. It showed a detection sensitivity of up to 7.51×102 copies·μL−1, which was 100 times greater than the conventional PCR can deliver, a repeatability with a coefficient variations (CV) of less than 1% on intra- and inter-batch tests, and a positive detection rate of 17.3% on 81 clinical samples. Conclusion The newly established SYBR-Green I RT-qPCR was specific, sensitive, repeatable, and considered adequate for early and rapid detection of ENTV-2 in goats.
2021, 36(7): 785-792.
doi: 10.19303/j.issn.1008-0384.2021.07.008
Abstract:
Objective Rabbit polyclonal antibodies against Elizabethkingia meningosepticum (Em) were prepared to establish an indirect ELISA detection to trace the pathogenic attack in organs of frogs (Rana spp). Method The strain RsB1151018NA of Em from a diseased R. spinosa was isolated, formalin-inactivated, and injected into a rabbit for the serum preparation. An optimized indirect ELISA using the rabbit polyclonal antibodies was developed for tracing RsB1151018NA. The rabbit immunoglobulin G was purified on a protein A column. The purified antibodies were marked with FITC and further purified on a desalting column Sephadex G-25 for subsequently tracing the pathogen in organs of the inoculated frogs. Results The obtained rabbit polyclonal antibodies showed a titer up to 1 ∶ 5.12×105, and 1 ∶ 1.6×104 after purification. The indirect ELISA assay on the polyclonal antibody was specific and sensitive in detecting Em without cross-reaction on other bacteria. It had a detection limit of 1.0×104 cfu·mL−1. According to the in vivo tracing test, RsB1151018NA distributed throughout the entire frog body by blood circulation with the most serious infections in the kidney, eyes, and brain. Conclusion The optimized indirect ELISA detection of Em was rapid, sensitive, and specific in tracing the bacterial infection on R. spp. It was considered applicable for early diagnosis of the “crooked-head disease” and breeding of healthy frogs for food and medicine.
2021, 36(7): 793-805.
doi: 10.19303/j.issn.1008-0384.2021.07.009
Abstract:
Objective Molecular information associated with the oviposition and reproduction of Tessaratoma papillosa was studied for control of the pest on lychee trees. Method Transcriptome sequencing of T. papillosa in various tissues and developmental stages was conducted. The vitellogenin and vitellogenin receptor genes were obtained by screening the transcriptome database and applying molecular cloning methods. Temporal and spatial expressions of the genes were analyzed using qRT-PCR. Result Three vitellogenin genes (i.e., T. papi_Vg1 Conclusion The structures and evolution of the 3 vitellogenin genes and one vitellogenin receptor gene were analyzed. The information on the spatiotemporal expressions of the genes would aid target selection in study for the control ofT. papillosa.
2021, 36(7): 806-816.
doi: 10.19303/j.issn.1008-0384.2021.07.010
Abstract:
Objective Effects of a bio-organic fertilizer on physicochemical properties and microbial community in rhizosphere soil of a banana field infected by Fusarium wilt disease were studied. Methods In a Fusarium wilt infected banana field, an random block design experiment on the application of a bio-organic fertilizer, Biofert, was conducted. Six months after banana seedlings were transplanted to the field, rhizosphere soil samples from lots with and without Biofert application were collected to determine the nutrient contents by chemical analysis and the microbial composition and diversity by high-throughput sequencing and bioinformatics analysis. Results Compared to control, the application of Biofert increased pH by 14.85%, the total N by 25%, and total P by 19.04%, but decreased the total Fe by 2.62% in the soil, while lowered the incidence of Fusarium wilt on the plants by 75%. In the rhizosphere soil, the Biofert-treated lots showed the relative abundance of, other than an 18.49% decrease on Proteobacteria, increases by 43.84% on Ascomycota, 90.64% on Chytridiomycota, 293% on Penicillium, 212% on Gibellulopsis, and 1193% on Talaromyces, 39.81% on fungal Chao1 index, 38.43% on ACE, and 86.85% on Shannon index. Conclusion Biofert application not only improved the soil quality but also significantly altered the structure and diversity of the microbial community in rhizosphere soil and contributed to the reduced incidence of banana wilt disease.
2021, 36(7): 817-825.
doi: 10.19303/j.issn.1008-0384.2021.07.011
Abstract:
Objective Diversity of culturable yeasts in rhizosphere soil of rice fields at Zayü County, Nyingchi City, Tibet was determined and its correlation with the environmental factors analyzed. Method Yeasts from the soil samples were isolated by dilution with a streaking plate method and identified by sequencing ITS domains of rRNA gene and conventional classification. Software R 3.6.1 was used to examine correlations between the yeast diversity and environmental factors. Result A total of 352 yeast strains of 10 genera and 13 species dominated by Cryptococcus podzolicus were isolated. The numbers extremely significantly correlated with the contents of total nitrogen (TN) and total phosphorus (TP) in the habitat rhizosphere soil. TN extremely significantly correlated to both Shannon-Wiener and Simpson diversity indices and significantly correlated to Pielou evenness index, but TP only significantly correlated to Shannon-Wiener diversity index. At species level, the abundance of Candida pseudolambica, Goffeauzyma gastrica, Papiliotrema aspenensis, and Solicoccozyma terricola significantly correlated to TN, G. gastrica and S. terricola extremely significantly and C. pseudolambica significantly correlated to TP, and P. aspenensis extremely significantly correlated to the water content (WC) in soil. Conclusion Different environmental factors affected differently on the rhizosphere yeast community on rice fields in the region. TN and TP in soil appeared to play a prominent role in that respect.
2021, 36(7): 826-835.
doi: 10.19303/j.issn.1008-0384.2021.07.012
Abstract:
Objective Aggregate distribution and organic carbon stability of farmland soil at Minqin Oasis under different methods of tillage were studied for improvements on the soil erosion eradication and agriculture sustainability in the area. Methods Taking advantage of the ongoing fixed position monitoring program at Minqin Oasis and utilizing a virgin land in the area as control (CK), 4 tilling methods including no-tilling (Tn), less-tilling (Tm), deep-loosening (Ts), and autumn turning-over (Tf) were performed to determine their effects on the aggregate composition and organic carbon stability of the soil. Results (1) In terms of soil aggregates, the tested tillage significantly increased the proportion of aggregates containing particles larger than 0.25 mm in the soil. Among them, Tm yielded 9.39% higher proportion than Tn, 11.38% higher than Ts, 6.09% higher than Tf, and 35.41 higher than CK in 0-20 cm soil, and 13.74% higher than Tn and 38.65% higher than CK in 20-40 layer. At the same time, Tm, Ts, and Tf significantly increased the mean weight diameter (MWD) and geometric mean diameter (GMD). (2) In terms of soil organic carbon stability, all 4 tilling methods significantly increased the content and cumulative mineralization of organic carbon in aggregates of different sizes in the soil layers. However, Tn resulted in greatest organic carbon content among them. It significantly increased carbon content over Ts, Tf, and CK by 18.58%, 39.53%, and 58.40%, respectively, in the soil at a depth of 0-20 cm, and 40.08%, 22.84%, and 60.93%, respectively, in the 20-40 cm layer. And the content decreased with reducing particle size and increasing depth of soil. In addition to agglomeration smaller than 0.25 mm, the cumulative mineralization of organic carbon treated by Tn was significantly higher than CK. Meanwhile, the tillage significantly reduced the organic carbon contribution proportion in soil by microaggregates smaller than 0.25 mm, as Tn, Tm, Ts, and Tf significantly reduced it by 32.89 %, 49.37 %, 26.61 %, and 38.88 %, respectively, over CK in 0-20 cm layer of the soil. Conclusion Tillage promoted the formation and stability of aggregates and also improved the carbon stability in soil. The less-tilling Tm and the no-tilling Tn minimized mechanical damage to the soil while increased the organic carbon content of large aggregates in surface and tillered soil. Tn was especially conducive to the carbon fixation, and Tm to the stability of soil. Thus, those two methods were recommended for farming in the region.
2021, 36(7): 836-842.
doi: 10.19303/j.issn.1008-0384.2021.07.013
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Objective Relationship between heavy metal contents in Dictyophora rubrovalvata and the soil the mushrooms were cultivated on was analyzed to understand the migratory pattern and pollution control. Method Contents of Cd, Pb, Hg, As, and Cr in stipe+skirt, receptacle, and cap of D. rubrovalvata as well as the overlying soil on the cultivation bed were analyzed to decipher the correlation between them. Result Contents of the heavy metals in D. rubrovalvata ranked Cd＞Cr＞As＞Pb＞Hg with a coefficient of variation ranging from 15.38% to 65.66%, while that in the soil Cr＞Pb＞As＞Cd＞Hg. Among the 5 heavy metals, only Cd in soil exceeded the safety standard. The enrichment coefficients of Cd in the 3 parts of D. rubrovalvata surpassed 1.5, while that of As less than 0.5 and those of Pb, Hg, and Cr below 0.1. A significant Pearson correlation was found between Pb and Cr at P＜0.01 (bilateral), but not among other heavy metals.The correlation between heavy metal elements in D. rubrovalvata and heavy metal elements in soil was statistically analyzed,the results showed that the other four elements had negative correlation except Hg. Conclusion The tested D. rubrovalvata was heavily contaminated with Cd, clean on Hg, and relatively clean on Pb or As. The Nemerow indexing put all parts of the D. rubrovalvata seriously contaminated by heavy metals. There were significant differences in the enrichment ability of different heavy metal elements. Except for the relative enrichment of Cd, the other four elements were relatively depleted. According to Pearson correlation analysis, there is a synergistic effect between Pb and Cr, and the correlation between other heavy metals is not obvious.
2021, 36(7): 843-854.
doi: 10.19303/j.issn.1008-0384.2021.07.014
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Objective Bacillus spp that contribute to the fermentation of Camellia oleifera seed shells were isolated for effective composting of the waste material. Method The microbial community in natural camellia seed shell compost found in Guangxi was studied using the high-throughput sequencing technology. Suitable culture medium to foster the growth of richly diverse Bacillus spp from the compost was selected. Flora isolation by dilution with a streaking plate method followed. The hydrolase activities of the isolates were determined by using the hydrolysis circle method and enzyme activity analysis, the species identified by a 16S rDNA analysis, and the phylogeny constructed by MEGAX. The content of humic acid in the compost was measured by a potassium dichromate method. Result Bacillaceae was the dominant family in the compost. It accounted for 55.58% of all isolated flora. Among the 15 Bacillus isolates, 6 exhibited activities of amylase, cellulase, and protease, one of amylase and cellulase, and 2 of protease or protease. Strain YX11 showed a protease activity of 27.07±3.28 U·mL−1, an amylase activity of 123.97±3.19 U·mL−1, and a cellulase activity of 15.75±0.23 U·mL−1. In the presence of numerous Bacillus spp that secreted varieties of hydrolases, formation of humic acid in the compost was enhanced. Conclusion Some of the isolated strains, such as B. cereus YX02 and B. flexus FYF01, might warrant further investigation to develop microbial inoculants for efficient composting camellia seed shells.
2021, 36(7): 855-860.
doi: 10.19303/j.issn.1008-0384.2021.07.015
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Objective The physical properties of maifanshi, a volcanic rock, were modified to improve its porosity and adsorption to be used as an immobilization carrier for natto fermentation bacteria that was further added with protective agents to extend the shelf life of viable Bacillus natto. Method Maifanshi was treated by acid, alkali, or salt to modify the porosity and surface adsorption property as a microbial carrier. Various protective agents, such as glucose, dextrin, and/or starch were incorporated to help prolong the viability of the imbedded B. natto powder. Result (1) The optimum conditions for B. natto culture included 40 ℃ and pH 7.5. (2) The maximum viable bacteria count was the highest at 13.17×108 CFU·g−1 on the maifanshi carriers modified by 0.5 mol·L−1sodium chloride solution. It was followed by a count of 12.7 ×108 CFU·g−1 on maifanshi treated by sulfuric acid, 12.6×108 CFU·g−1 on maifanshi treated by hydrochloric acid, and 11.9×108 CFU·g−1 on maifanshi treated by sodium hydroxide. (3) The viable B. natto counts after 6 months in storage on control was 2.91×108 CFU·g−1 as compared to those immobilized on the carriers with addition of 2% dextrin, 2% glucose, or 2% starch being 4.1×108 CFU·g−1, 5.42×108 CFU·g−1, and 4.63×108 CFU·g−1, respectively. The retention of viable B. natto on the NaCl-treated maifanshi with the addition of dextrin was 31%, that of glucose 41%, that of starch 35%, and that of control 22%. Conclusion As a bacteria carrier, maifanshi could be significantly further improved on the adsorption capacity by modification such as NaCl treatment. With an addition of 2% glucose on the immobilized system, the retained viable B. natto count could rise 1.86 times over control in 6 months of storage. It appeared that this study had paved the way of developing a practical application of maifanshi for natto fermentation industry.
2021, 36(7): 861-866.
doi: 10.19303/j.issn.1008-0384.2021.07.016
Abstract:
Objective Effect of drying technology on the nutritional quality of Tremella fuciformis Berk was studied. Method The national standards on the nutritional quality of edible fungi, such as contents of total sugar, reducing sugar, protein, and amino acids, were the indices used to evaluate 4 drying technologies in producing the dehydrated product. The FAO/WHO indexing system was applied to gage the protein nutrition. Dehydration of T. fuciformis employed either spent culture substrate for fuel in a factory oven (M1), spent culture substrate and wood chips for fuel in a factory oven (M2), spent culture substrate for fuel in a workshop oven (M3), or an industrial electric oven (M4). Results Water-soaking of the fungi prior to dehydration showed no significant effect on the contents of protein, sugar, amino acids, and sulfur dioxide in the dried product (P＞0.05). However, the various drying methods resulted in quality differentiations among them. The contents of total sugar and reducing sugar in the dried T. fuciformis prepared under M2 and M3 were significantly higher than those under M4 (P＜0.05). The amino acid contents of the products made by different technologies did not differ significantly (P＞0.05). The nutritional grading based on amino acids ranked the dried mushrooms from those made by M1 at a score of 80.52, to M4 of 79.55, M3 of 79.15, and M2 of 77.80. All dried fungi products had a well-balance nutritional composition with lysine being the top restricted amino acid. Conclusion The total sugar and amino acids in the dehydrated T. fuciformis were not affected by the pre-soaking but significantly by the drying process. Either drying by using spent culture substrate and wood chips for fuel in a factory oven (M2) or by using spent culture substrate for fuel in a workshop oven (M3) retained the nutrients more effectively than other methods. Incidentally, there was no sulfur dioxide residue detected in the dried T. fuciformis produced by the process currently practiced by the industry.
