Welcome to Chinese Journal of Tropical Crops,

Table of Content

    25 July 2020, Volume 41 Issue 7 Previous Issue    Next Issue
    Omics & Biotechnology
    Analysis of Transcriptome Characteristics of Areca at Different Developmental Stages
    YA Huiyuan,CHEN Ye,ZHANG Yansong,XU Qitai
    2020, 41 (7):  1279-1287.  doi: 10.3969/j.issn.1000-2561.2020.07.001
    Abstract ( 465 )   HTML ( 16120 )   PDF (1279KB) ( 705 )  

    Areca (Areca catechu L.) is one of the four primary medicinal plants in south China. In the study, the high-throughput sequencing technology was used to sequence the transcriptome of the peel and kernel in different periods to find differentially expressed genes in different developmental stages. Among the peels, 4491 differential genes were divided, of which 617 differential genes were involved in 111 KEGG metabolic pathways,257 differential genes with 82 pathways in the biological process metabolism class, and a total of 27 genes with 5 genes involved in the secondary metabolic pathway. There were 5443 differential genes in the betel nut kernel, according to the KEGG pathway annotation results, 898 differential genes were involved in 118 pathways, 466 differential genes were annotated on biological metabolic pathways for 89 pathways, 53 genes involved in secondary metabolism with 7 secondary metabolic pathways involved. Further analysis showed that with the development of fruit, 80% of the secondary metabolic pathways in the pericarp showed a down-regulated expression of the genes, while 71.4% of the secondary metabolic pathways in the kernel showed up-regulated expression. The results of the study preliminarily revealed the overall characteristics of the transcriptome of different tissues and different developmental stages of areca nut, and found that the expression of secondary metabolism-related regulatory genes in betel nut and pit were observed in different stages, which was the medicinal development and secondary of betel nut.

    Figures and Tables | References | Related Articles
    Transcriptome Data Analysis of Artocarpus heterophyllus Stems and Leaves
    PAN Min,YU Xudong,CAI Zeping,LI Jiajia,LUO Jiajia,ZHOU Dan,CHU Wenqing,QU Qian
    2020, 41 (7):  1288-1297.  doi: 10.3969/j.issn.1000-2561.2020.07.002
    Abstract ( 448 )   HTML ( 13 )   PDF (5177KB) ( 265 )  

    Artocarpus heterophyllus is an important woody plant in tropical regions withhigh economic value. This test used the normal and chlorophyll deficient mutant of A. heterophyllus seedlings as the research materials. The transcriptome of the stems and leaves was sequenced by PacBio Sequel, 95 701 isoformswerefinally found. After cluster and polish, using NR, NT, GO, KOG, KEGG, Swiss-Prot and InterPro 7 databases for functional annotation, a total of 93 367 transcripts were annotated. There were 92 187 (NR), 90 326 (NT), 74 548 (Swiss-Prot), 75 396 (KEGG), 77 022 (KOG), 81 906 (InterPro) and 65 500 (GO) transcripts annotated in the seven databases respectively. In addition, a total of 85 091 CDS and 55 608 SSR sequences were detected, 4 753 transcription factors, 1 667 transcriptional regulators and 4 710 receptor-like kinases were predicted.

    Figures and Tables | References | Related Articles
    Molecular Cloning and Expression Analysis of Rhythms Clock Output Gene HpGI from Hylocereus polyrhizus
    XIAO Tujian,MA Yuhua,YUAN Qifeng,XIE Pu,MAO Yongya,YAN Jiawen,LIAO Shiqin
    2020, 41 (7):  1298-1304.  doi: 10.3969/j.issn.1000-2561.2020.07.003
    Abstract ( 320 )   HTML ( 12 )   PDF (2139KB) ( 270 )  

    Rhythms clock output gene GIGANTEA promotes flowering via the photoperiod pathway. To analysis the function of GIGANTEA homologous gene in pitaya [Hylocereus polyrhizus (Weber) Britton & Rose], the open reading frame (ORF) sequence was cloned through RT-PCR. The ORF of Hylocereus polyrhizus GIGANTEA (HpGI) is 3537 bp, encoding 1178 amino acids, and the GenBank accession number is MK609546. The phylogenetic analysis showed that HpGI and Beta vulgaris GIGANTEA are the closest in molecular evolution distance, followed by Spinacia oleracea GIGANTEA and Gypsophila paniculate GIGANTEA. It was speculated that HpGI was located in the nucleus, and it was a non-secretory protein. No signal peptide and transmembrane helix domain were found. The results of quantitative RT-PCR revealed that the expression level of HpGI gene in the stem and flower bud was significantly higher than that in the stem bud, peel and root. Moreover, the transcription of the HpGI gene was significantly induced by the 8 d night-breaking treatment, compared to the untreated samples. It was deduced that HpGI may promote flowering via the photoperiod pathway in pitaya.

    Figures and Tables | References | Related Articles
    Bioinformatics Analysis of MYB Transcription Factor Family in Blumea balsamifera
    GUAN Lingliang,ZHA Ying,BAI Lin,YU Fulai,CHEN Zhenxia,CHEN Xiaolu,XIE Xiaoli,WANG Kai,HUANG Mei
    2020, 41 (7):  1305-1312.  doi: 10.3969/j.issn.1000-2561.2020.07.004
    Abstract ( 393 )   HTML ( 11 )   PDF (4343KB) ( 230 )  

    MYB is one of the largest transcription factors family and has a wide range of biological functions in plants. Based on the full-length transcriptome database of Blumea balsamifera, DNAMAN 6.0, MEGA 5.05 software and ProtParam, WebLogo and SOPMA online sites were used to analyze and predict the types, physicochemical properties, advanced structure of amino acid sequence, conserved domain and phylogenetic evolution of MYB transcription factor in B. balsamifera, The results showed that 127 BbMYB genes were extracted, and 47 protein sequences with MYB conserved domains were predicted. According to the domain, they could be divided into 1R-BbMYB and R2R3-MYB. Meanwhile, the R2-BbMYB and R3-BbMYB motifs contained three conserved tryptophans, while R1-BbMYB contained only two. Morever, all proteins of MYB family in B. balsamifera were hydrophilic with high thermal stability and rich in basic amino acids. And most of the proteins were irregular curls except the R2R3-BbMYB3, R2R3-BbMYB4 and 1R-BbMYB15. The MYB family of B. balsamifera evolved into two major categories and six subcategories by comparing with the evolutionary tree of Arabidopsis thaliana. It would provide a method for further research on the functional identification of the MYB family in B. balsamifera by the adjacent or evolutionary relationship with the same function.

    Figures and Tables | References | Related Articles
    Analysis of Expression Pattern and Construction of Knockout Vector of PChyd Gene of Paecilomyces cicadae
    WANG Lifang,PENG Yao,DANG Xiangli,YE Liang,LI Shuangjiao,XU Huihui,DU Juan,DONG Yude
    2020, 41 (7):  1313-1320.  doi: 10.3969/j.issn.1000-2561.2020.07.005
    Abstract ( 282 )   HTML ( 18 )   PDF (6310KB) ( 215 )  

    In order to investigate the function of PChyd of Paecilomyces cicadae, the gene was cloned according to the genomic data of P. cicadae, and the bioinformatics of the gene were analyzed by the NCBI database and the Expasy online tools. The expression pattern of PChyd was analyzed under different culture conditions or stages by qRT-PCR. The knockout vector of the gene was constructed by molecular biological methods. The open reading frame of PChyd was 303 bp encoding 100 aa. Domain analysis revealed that the gene contained a 22 aa signal peptide region and a 70 aa hydrophobin functional region. Phylogenetic analysis showed that the relationship of P. cicadae PChyd was close to Cordyceps confragosa hydrophobin. Expression pattern analysis showed that the expression level of PChyd in mycelium in PDA, appressorium and blastospore were significantly higher than that of the other two samples, and the expression level was the highest in blastospore among five samples, which indicating that this gene had important function in the initial stage of the infection of P. cicadae and in the colonization stage of insect blood. The results of gel electrophoresis and sequencing showed that the knockout vector of the gene was successfully constructed. The research would lay a foundation for further exploring of the pathogenic mechanism of PChyd and engineering this entomopathogenic fungus P. cicadae.

    Figures and Tables | References | Related Articles
    Germplasm Resources, Genetics & Breeding
    Phenotypic Characteristics and Genetic Analysis of a Rice PTGMS Line Mutant H08S with Yellow Leaf
    LIN Qiuyun,XIE Zhenyu,LONG Kaiyi,HE Zhizhou
    2020, 41 (7):  1321-1325.  doi: 10.3969/j.issn.1000-2561.2020.07.006
    Abstract ( 270 )   HTML ( 8 )   PDF (2985KB) ( 224 )  

    PTGMS lines are susceptible to light and temperature conditions during their fertility sensitive period, which results in fertility fluctuation and seriously affects the purity of the original or hybrid seeds of the male sterile lines. In this paper, the temperature sensitivity and chloroplast ultrastructure of a rice PTGMS mutant H08S with yellow leaf were analyzed, and the genetic model of the mutant gene was analyzed by constructing two segregated populations. The results showed that the phenotype of mutant H08S was affected by temperature, and it was a low temperature expression type of leaf color mutant. The chloroplast structure of mutant H08S was abnormal, and the lamellar structure of thylakoid was reduced. This indicated that the mutation of H08S gene affected the normal development of chloroplast. F2 population and BC1F1 population were constructed with mutant H08S and ‘Nipponbare’ and ‘02428’, respectively. The isolation of leaf color phenotypes was observed and counted, and chi-square test was carried out. The results showed that the mutant trait was controlled by a pair of recessive single genes.

    Figures and Tables | References | Related Articles
    Evaluation of 30 Species of Clausena anisum-olens (Blanco) Merr. Germplasm Resources Based on Factor Analysis and Cluster Analysis
    ZHANG Tao,HE Peng,SONG Haiyun,XU Peng,MO Qingdao,QIN Zhenshi,WEI Yuanrong,TANG Xiuhua,WANG Wenlin,ZHENG Shufang
    2020, 41 (7):  1326-1334.  doi: 10.3969/j.issn.1000-2561.2020.07.007
    Abstract ( 386 )   HTML ( 17 )   PDF (1216KB) ( 305 )  

    In order to evaluate the germplasm resources of 30 species of Clausena anisum-olens (Blanco) Merr., nine fruit traits including weight of single fruit, fruit equatorial diameter, fruit transverse diameter, fruit shape index, weight of single seed, seed equatorial diameter, seed transverse diameter, edible rate, soluble solid content were measured and analyzed by statistical analysis. The variation of weight of single fruit of C. anisum-olens (Blanco) Merr. was the most significant, while the variation of fruit shape index was the most non-significant. The soluble solid content was not correlated with the other eight indices significantly, and there was significant and extremely significant correlation between the other indexes. Thirty species of C. anisum-olens (Blanco) Merr. germplasm resources were clustered into three categories by factor analysis and cluster analysis. There was a certain correlation between fruit trait and geographical origin. Fruit traits of 13 germplasm from Longzhou County and Ningming County were the best.

    Figures and Tables | References | Related Articles
    Evaluation of Adaptability of Different Tea Cultivars in Hubei Based on Principal Components Analysis
    MA Linlong,CAO Dan,LIU Yanli,JIN Xiaofang
    2020, 41 (7):  1335-1346.  doi: 10.3969/j.issn.1000-2561.2020.07.008
    Abstract ( 315 )   HTML ( 35 )   PDF (1416KB) ( 499 )  

    To accurately evaluate the adaptability of 19 tea cultivars in Hubei Province. In this study, the major agronomic traits such as survival rate, phenological phase, yield traits, ensory quality, and stress resistance were systematically analyzed by comparison with ‘Fudingdabaicha’ (CK), and the adaptability of different tea cultivars in Hubei Province was comprehensively evaluated by principal component analysis. Three principal components including yield - resistance factor, phenological phase factor and quality factor were determined, and the cumulative variance contribution rate was 76.96%. The composite scores of ten cultivars were higher than that of CK, of which ‘Chanong 98’, ‘Echa12’, ‘Shancha1’, and ‘Lanlixiang’ were the most suitable application area in Hubei or similar areas. The composite scores of nine cultivars were lower than that of CK, of which ‘Baiye1’, ‘Zhonghuang1’, ‘Caoxi1’, and ‘Niaowang106’ were not the appropriate application area in Hubei or similar areas.

    Figures and Tables | References | Related Articles
    Plant Cultivation, Physiology & Biochemistry
    Sugarcane Yield and Soil Potassium Balance in Potassium Application of Four Consecutive Years
    HUANG Zhenrui,ZHOU Wenling,AO Junhua,CHEN Diwen,HUANG Ying,JIANG Yong,LI Qiwei
    2020, 41 (7):  1347-1353.  doi: 10.3969/j.issn.1000-2561.2020.07.009
    Abstract ( 323 )   HTML ( 8 )   PDF (1384KB) ( 255 )  

    A four-year (2014 to 2017) potassium fertilizer field experiment designed by a random block with cultivar ‘Yuetang 03-393’ (‘Yuetang 60’) and five K2O levels of 0, 225, 450, 675 and 900 kg/hm2 respectively was conducted to evaluate the effects of the long-term application of potassium fertilizers on sugarcane yield, agronomy efficiency, plant potassium (K) uptake, potassium use efficiency and soil potassium content. Under a certain K2O application range, with the increase of potassium application rate, the agronomy efficiency, yield and potassium use efficiency of sugarcane increased and then decreased, while the output-input ratio was down. The yield and potassium use efficiency of the treatment with 450 kg/hm2 K2O were the highest, and the agronomy efficiency and output-input ratio of the treatment with 225 kg/hm2 K2O were the best. With the increase of potassium fertilizer dosage, the potassium uptake, soil potassium content and potassium equilibrium coefficient of sugarcane plants increased, resulting in luxury absorption of plants, excessive soil potassium content, excessive apparent surplus and waste of potassium resources. The reasonable application of potassium fertilizers could increase the agronomic benefit and yield. However, the excessive application of potassium fertilizers could reduce the agricultural effect and potassium use efficiency, and also result in the waste of resources and loss of K nutrients. Considering agronomy efficiency, fertilizer use efficiency, apparent balance of soil potassium and comprehensive benefits, the recommended amount of potassium fertilizers for sugarcane is K2O 225-450 kg/hm2.

    Figures and Tables | References | Related Articles
    Effect of Nitrogen Reduction on Yield Stability of Sugarcane-Soybean Intercropping System
    XU Xia,GOU Yonggang,LUO Shasha,WANG Yushu,YU Lingling,WANG Jianwu
    2020, 41 (7):  1354-1365.  doi: 10.3969/j.issn.1000-2561.2020.07.010
    Abstract ( 303 )   HTML ( 9 )   PDF (2100KB) ( 274 )  

    Sugarcane is an important economic crop in South China. The yield and quality are declined because of the long-term practice of monoculture agriculture and high chemical nitrogen application. Intercropping system is a sustainable and stable agricultural practice that enables the effective utilization of water, nutrient and light. In the paper, a field experiment was conducted at Experimental Center of South China Agriculture University (23°08°N, 113°15°E) for 10 years (from 2009 to 2018) to investigate the dynamic changes of sugarcane-soybean and system yields under two nitrogen levels [reduced rate 300 kg/hm2(N1) and conventional rate 525 kg/hm2 (N2)] and four cropping patterns [sugarcane monocropping (MS), soybean monocropping (MB), sugarcane-soybean (1∶1) intercropping (SB1), and sugar-cane-soybean (1∶2) intercropping (SB2)]. The study analyzed the dynamic change of land equivalent ratio and evaluated the stability of system yield by Wi2 (Wricke’s ecovalence), CV (coefficient of variation) and SYI (sustainability index), aiming to explore the effects of reduced nitrogen application on the time stability of sugarcane-soybean intercropping system in Guangdong, China. The yield of sugarcane, soybean and the total system under different treatment showed obvious annual dynamic changes and was significantly affected by different years and planting patterns. Nitrogen application level did not affect the yield of sugarcane, soybean and the system yield significantly. The land equivalent ratio (LER) of all intercropping systems was greater than 1 (between 1.09 and 1.97) for 10 years, and the SB2-N1 optimally improved the land utilization rate among all treatments. There was no significant difference in Wi2and CV for sugarcane yield, but the SYI of MS-N1 was significantly higher than that of MS-N2. Meanwhile, the Wi 2 value of monocropping soybean was significantly higher than that of intercropping pattern, and the yield stability of monocropping soybean was lower than that of intercropping soybean. And the stability of soybean yield under reduced nitrogen application was higher than that under conventional nitrogen application. Planting pattern had a significant effect on the stability of the total yield of the system, and intercropping soybean increased the stability of the total yield of the system. The sucrose content and gravity purity of sugarcane juice was decreased with the increase of cultivation years, and the sucrore content and fiber content of bagasse, the sugar brix, sugar pol, apparent purity of sugarcane juice was not influenced by cropping year. In addition, the quality of sugarcane was not influenced by different cropping patterns and nitrogen rates in the same year, which indicating that sugarcane quality was stable under different treatments. From 2010 to 2018, soil pH, organic matter and total nitrogen were decreased significantly, but there was no significant difference in total phosphorus, available phosphorus, and available potassium in all treatments except for the soybean monoculture treatment. Sugarcane continuous cultivation and continuous application of chemical fertilizer led to the decrease of soil organic matter and pH. Reducing nitrogen application and intercropping soybean are sustainable and green production models for efficient utilization of resources and stable system yield in sugarcane producing areas in Guangdong, China, but organic fertilizer application and promotion of sugarcane leaf returning technology are needed to improve sugarcane field fertility.

    Figures and Tables | References | Related Articles
    Influence of Pruning Intensity on New Branch Growth and Flowering and Fruiting of Sapindus mukorossi
    HUANG Qiuliang,FAN Huihua,ZHANG Tianyu,YAO Xiangming,TANG Xinghao,HUANG Yu
    2020, 41 (7):  1366-1372.  doi: 10.3969/j.issn.1000-2561.2020.07.011
    Abstract ( 406 )   HTML ( 7 )   PDF (1297KB) ( 229 )  

    Using the four-year-old start fruiting Sapindus mukorossi clones as the material, the new branch sprouting, growth and flowering and fruiting under different pruning intensities, i.e., light (T1), moderate (T2), severe trimming (T3) and with no trimming (CK) were studied. Pruning intensity significantly (P<0.05) or extremely significantly (P<0.01) affected the new branch sprouting number, length and base diameter of S. mukorossi clones. The number of new branches (-0.3426) and the new branch diameter (0.7035) were found to be the main factors influencing the yield of S. mukorossi yield, and total number of new branches and the new branches diameter affected the nutrient distribution of the new branches. Significant or extremely significant differences in total number of new branches, number of flowering branches, flowering branch rate, number of vegetative branch, bearing branch ratio and fruit yield were found among the four treatments. Moreover, the average fruit yield per plant of T1, T2 and T3 was respectively 4.99 times, 7.28 times and 1.54 times higher than that of CK. Results obtained in the study indicated that pruning affected a lot in regulating the quantity and quality of new branches and in influencing the nutrient distribution of new branches. Besides, moderate pruning of young S. mukorossi trees could increase the fruit yield of S. mukorossi.

    Figures and Tables | References | Related Articles
    Photosynthetic Characteristics and Chlorophyll Fluorescence Characteristics of Ten Ornamental Bamboo Species
    QIAO Yina,LI Yunge,LIU Pin,LIU Kai,ZHANG Xiaoqing,RONG Jundong,CHEN Liguang
    2020, 41 (7):  1373-1379.  doi: 10.3969/j.issn.1000-2561.2020.07.012
    Abstract ( 315 )   HTML ( 7 )   PDF (1410KB) ( 260 )  

    Ten different ornamental bamboo species were selected to study the photosynthetic characteristics and chlorophyll fluorescence parameters of different bamboo species. Principal component analysis was used to comprehensively evaluate the species and to screen species whicn meeting urban greening cultivation. During the whole growth period, the chlorophyll content of Ambusa ventricosa was the highest, and that of Sinobambusa tootsik was the lowest. The Pn value of Bambusa affinis, Gigantochloa verticillata, Bambusa multiplex f. Alphonse-karri and Bambusa albo- lineata Chia was 3.5 μmol/(m 2?s) or more, and that of Bambusa eutuldoides var. viridi-vittata was 1.34 μmol/ (m2?s), the lowest. There was a significant correlation between net photosynthetic rate and transpiration rate (Tr), stomatal conductance (Gs) and water use efficiency (WUE) of different species. The potential photochemical activity (Fv/Fo) and PSII effective photochemical quantum efficiency (Fv/Fm) value of PSII of B. eutuldoides var. viridi-vittata, G. verticillata and S. tootsik were relatively high. Phyllostachys nigra (Lodd. ex Lindl.) Munro and B. multiplex f. Alphonse-karri were relatively low. B. albo-lineata Chia, S. tootsik and B. affinis had higher non-photochemical quenching coefficient (qN), photochemical quenching coefficient (qP) and PSII photochemical efficiency (Yield/ΦPSII). It could be seen that under the same growth environment, the photosynthetic utilization ability, photosynthetic efficiency and light adaptability of different ornamental bamboos were different, and there were significant differences. According to the comprehensive evaluation, G. verticillata, B. affinis and B. ventricosa are high-efficiency bamboo species, and the light is suitable for strong greening.

    Figures and Tables | References | Related Articles
    Pollen Germination in vitro and Cryopreservation Reserch of Anecphya Waterlily
    TANG Yuwei,LONG Lingyun,HUANG Qiuwei,SU Qun,CHI Zhaojin,LU Jiashi,MAO Liyan
    2020, 41 (7):  1380-1386.  doi: 10.3969/j.issn.1000-2561.2020.07.013
    Abstract ( 287 )   HTML ( 7 )   PDF (1779KB) ( 361 )  

    The pollens of Nymphaea ‘Moshen’ and three orginal Nymphaea accessions were used as the test material to study the optimal medium components for the pollen germination in vitro of Nymphaea and the method for prolonging pollen viability at low temperature. The single factor and orthogonal design were used to select the most suitable medium, and observe the germination rate of the pollens preserved at different temperatures. The optimum medium concentration for the pollens of the four accessions was different. The pollen viability varied among accessions. The pollen viability of N. immutabilis subsp. Immutabilis blue form and N. immutabilis subsp. immutabilis purple form was 43.90% and 45.63% respectively, and that of N. ‘Moshen’ and N. ‘Gigantea Albertde Lestang’ was 31.84% and 9.73%, relatively. The pollen of Nymphaea was not tolerant to storage, and lost the viability after 72 hours of storage at different temperatures. The results of the study could provide references for parents selection and pollen cryopreservation in hybrid breeding of Nymphaea.

    Figures and Tables | References | Related Articles
    Growth and Photosynthetic Characteristics of Coffee Double Roots Grafting Seedling
    SUN Yan,LIN Xingjun,LONG Yuzhou,DONG Yunping,ZHAO Qingyun,TAN Jun
    2020, 41 (7):  1387-1392.  doi: 10.3969/j.issn.1000-2561.2020.07.014
    Abstract ( 292 )   HTML ( 8 )   PDF (1263KB) ( 226 )  

    In order to improve the quality of coffee seedling, the seed seedlings of Caffea liberica No. 1 and Caffea canephora Reyan No. 1 were used as the grafting materials, and high-yielding clone C. canephora Reyan No. 1 was used as the scion. Biomass, root morphology characteristics, photosynthetic characteristics, height diameter ratio and seedling quality index among C. canephora Reyan No. 1 double roots grafting seedling (T1), C. liberica No. 1/ C. canephora Reyan No. 1 double roots grafting seedling (T2), C. liberica No. 1 double roots grafting seedling (T3) and conventional interspecific grafting seedling (CK, C. liberica No. 1 single root grafting seedling) were observed. Compared with CK, root tip number, pn, total biomass and seedling quality index of T1 and T2 were increased by 407.14% and 780.28%, 25.11% and 57.49%, 168.26% and 209.35%, 195.79% and 244.17%, respectively. The seedling quality of T1 and T2 was improved by raising plant root absorption and photosynthetic ability. The height diameter ratio of T3 was increased by 25.28%, and there was no significant difference in total biomass between CK and T3. Compared with the seedling of CK, the week seedling of T3 grew thinner and taller, and then grew into coffee tall-footed seedlings more easily. In summary, the advantage was evident in the plant growth of T1 and T2, particularly in T2 treatment.

    Figures and Tables | References | Related Articles
    Dynamic Content Variation Analysis of Polyphenols in Seven Leafy Sweet Potato Varieties (Lines)
    LIU Yi,YANG Xinsun,LEI Jian,WANG Lianjun,CHAI Shasha,ZHANG Wenying,SU Wenjin,JIAO Chunhai
    2020, 41 (7):  1393-1401.  doi: 10.3969/j.issn.1000-2561.2020.07.015
    Abstract ( 249 )   HTML ( 9 )   PDF (1368KB) ( 307 )  

    Polyphenol related materials which are mainly constituted by chlorogenic acids (CGAs) are one of the most important health protection components in leafy sweet potato. They play important roles for improving leafy sweet potato taste and processing quality. In this study, Folin-ciocalteu and HPLC methods were employed to determine the contents of total polyphenols and chlorogenic acids in seven leafy sweet potato varieties (lines) at 6 stages. The content of total polyphenols and CGAs in different varieties (lines) was significantly affected by stages and exhibited dynamic variation. All varieties (lines) showed the same content change trend from 45 days to 85 days after planting. They first increased and then decreased, reaching the maximum level in 65 days, however, there were differences in the change trend from 85 days to 140 days after planting. The variation coefficient of the substances demonstrated that 5-CQA (5-O-caffeoylquinic acid), 3,4-diCQA (3,4-di-O-caffeoylquinic acid), 3,5-diCQA (3,5-di-O-caffeoylquinic acid) and 4,5-diCQA (4,5-di-O-caffeoylquinic acid) displayed a wider range variation than total polyphenols, with the range of 30.80% to 59.88%, 45.18% to 112.90%, 45.19% to 114.11%, 41.82% to 118.62% and 19.82% to 40.04%, respectively. The overall variation analysis inferred that the total polyphenols and chlorogenic acids were significantly affected by sampling times, varieties (lines) and the cross effect of both. Moreover, the total polyphenols and CGAs were significantly positively correlated. The investigation of polyphenol related materials of leafy sweet potato could lay a foundation for industiral exploration.

    Figures and Tables | References | Related Articles
    Effect of Carbon Ion Beams Irradiation on Seed Germination, Survival and Seedling Growth of Hylocereus polyrhizus
    WU Zhijiang,LIANG Guidong,LIAO Yijin,HUANG Lifang,HUANG Fengzhu,LU Guifeng,CHEN Dongkui,DENG Haiyan
    2020, 41 (7):  1402-1407.  doi: 10.3969/j.issn.1000-2561.2020.07.016
    Abstract ( 271 )   HTML ( 5 )   PDF (1512KB) ( 279 )  

    In order to explore the damage effect of carbon ion beams irradiation on seeds and determine the suitable mutagenic irradiation doses, the effects of carbon ion beams on seed germination, survival and seedling growth were investigated by irradiating the dry seeds of red pitaya (Hylocereus polyrhizus) at various doses of12C6+ ion beams (0, 15, 30, 45 and 60 Gy). The results showed that most of the seeds could germinate normally at the irradiation doses ranging from 0 to 60 Gy, and the effects of carbon ion beams on the germination rate were not significant, but some certain inhibitory effects on germination potential and germination index were observed. It could significantly promote the shoot height, but inhibit the radicle length, cotyledon length and width to varying degrees. Carbon ion beams irradiation had a very significant dose effect on the survival rate of the seedlings which significantly decreased with the irradiation dose. The semi-lethal dose (LD50) of the seeds of red pitaya irradiated by carbon ion beams was 24 Gy. The recommended irradiation doses is ranged from 15 to 30 Gy. Those results would provide dose references and guidance for the subsequent study of carbon ion beams mutation breeding of pitaya.

    Figures and Tables | References | Related Articles
    Plant Protection & Bio-safety
    Application Effect Evaluation of Solar Energy Self-Controlled Multifunctional Pest Trap Lamp on Areca catechu L.
    REN Chengcai,WU Chaobo,ZHU Mingjun,HAN Wensu,RUI Kai,LYU Chaojun,ZHANG Yan
    2020, 41 (7):  1408-1414.  doi: 10.3969/j.issn.1000-2561.2020.07.017
    Abstract ( 295 )   HTML ( 7 )   PDF (1287KB) ( 255 )  

    The effect of solar energy self-control multi-function and multi-mode trap lamp trapping pest on Areca catechu L. was studied. A total of 255 924 pests in 8 orders, 26 families and 46 species in 240 days were trapped, among which the number and weight of Lepidoptera pests reached 64.33%. The number and weight of trap lamp increased from August to November, decreased from December to February, and increased after March. The change of trap number was consistent with the occurrence law of local pests, and the beneficial insects accounted for only 0.80% of total pests. The pest grade of Areca catechu L. in the control area of trap lamp was less than that of the non-trap lamp by 1-3 grades, and the occurrence level of insect pests was less than ++. The fruit setting rate in the control area of trap lamp was significantly higher than that in the area without trap lamp at the beginning of flowering and fruiting. The fruit falling rate was significantly reduced, which made the yield of trap lamp reach 10.96 kg per plant, 36.61% higher than that of the area without trap lamp. The results showed that the trap had a wide spectrum of insect traps and strong trapping effect. It could reduce the occurrence of insect pests, increase fruit setting rate and increase yield when it is used in A. catechu L. orchard.

    Figures and Tables | References | Related Articles
    Genetic Analysis of Resistance of Watermelon Cultivars ‘Heipi’ to Aphis gossypii
    CHEN Qing,LIANG Xiao,WU Chunling,LIU Ying,XU Xuelian
    2020, 41 (7):  1415-1419.  doi: 10.3969/j.issn.1000-2561.2020.07.018
    Abstract ( 327 )   HTML ( 6 )   PDF (1527KB) ( 200 )  

    To get stable resistant watermelon cultivars, the genetic analysis of the resistance of watermelon cultivar ‘Heipi’ to Aphis gossypii was proceeded by the ratio of aphid number at seedling in a greenhouse added with RAPD and SCAR. The reciprocal-hybrid F1 of ‘Heipi’ and ‘Hualv’ was resistant while the resistant and susceptible plants in F2 hybrid fitted the separation ratio of 3:1 by χ 2test. Four resistant cultivars, four susceptible cultivars, ten resistant F2 single plants and ten susceptible F2 single plants were verified with screened RAPD WO4600 and SCAR WO4-S530. The results indicated that the resistance of the parent ‘Heipi’ to A. gossypii was controlled by a dominant single gene which was stably inherited, ‘Heipi’, ‘Lvmeiren’, ‘Heimeiren’ and ‘Huilan’ were aphid-resistant cultivars, ‘Hualv’, ‘Fengguang’, ‘Huibao’ and ‘Tianmeiren’ were aphid-susceptible cultivars.

    Figures and Tables | References | Related Articles
    Functional Analysis of Serine/Threonine Phosphatase MoPpz1 in Magnaporthe oryzae
    XIE Yuman,ZHANG Tian,CAI Yan,ZHANG Lianhu,ZHANG Dongmei
    2020, 41 (7):  1420-1426.  doi: 10.3969/j.issn.1000-2561.2020.07.019
    Abstract ( 299 )   HTML ( 9 )   PDF (4468KB) ( 243 )  

    Magnaporthe oryzae is a fungal pathogen causing blast disease in different stages of rice. In eukaryotes, the highly conserved protein kinase CK2 contains two regulatory subunits and two catalytic subunits. MoCK2, CK2 homologus in M. oryzae, is encoding by three genes, MoCKb1 and MoCKb2 encode two different regulatory subunits, and MoCKa encodes its catalytic subunit. MoPpz1, one of serine/threonine phosphatase obtained by pull-down assay of MoCKa-GFP in M. oryzae, was researched at its function by reverse genetic approache and homologous recombination principle in our study. It was found that Ppz1 had different functions in various fungi by bioinformatics analysis, and showed that Ppz1 and it’s homolog proteins in other model fungi had highly identity in the protein sequences. ΔMoppz1 mutant obtained by gene knock-out and genotyping screen, while the mutant was not affected in vegetative growth and conidial production, the mutant showed development delay of conidium from germination to appressorium and reduced pathogenicity to rice after phenotypic assay comparing with wildtype strain Ku80. Confocal laser scanning microscopy analysis showed that MoPpz1 was localized in the cytoplasm of hyphae, conidium and appressorium. In conclusion, the protein phosphatase MoPpz1 may be involved in the regulation of conidial germination, appressorial formation in M. oryzae and pathogenicity to rice.

    Figures and Tables | References | Related Articles
    Post-harvest Treatment & Quality Safety
    Metabolism of Reactive Oxygen Species During Development of Black Heart Disease in Post-harvest Pineapple
    CHANG Jinmei,HE Yong,ZHANG Lubin
    2020, 41 (7):  1427-1433.  doi: 10.3969/j.issn.1000-2561.2020.07.020
    Abstract ( 303 )   HTML ( 6 )   PDF (1700KB) ( 243 )  

    In order to explore the metabolism pathway of reactive oxygen species (ROS) related to the development of black heart disease in postharvest pineapple, ‘Paris’ pineapple as the material was stored at room temperature and observed for the incidence of black heart disease. The pulp along the equator and the pulp of healthy and diseased parts were sampled separately every 3 days. The incidence of black heart disease and the browning degree of pulp were tested. At the same time, the activities of lipoxygenase (LOX), and the key enzymes of ROS metabolism (POD, CAT, SOD), and the contents of malondialdehyde (MDA), ascorbic acid (AsA), flavonoids and glutathione (GSH) were tested during the course of the storage. The results showed that the black heart disease of pineapple appeared at the 6th day and the incidence rate increased to 100% at the 15th day. From the 6th day to the 9th day, the browning was the fastest. Compared with healthy parts, the diseased tissue was accompanied by increase of LOX activity and MDA accumulation, significant decrease in AsA content and POD, CAT activities, and rapid increase in flavonoid content. The glutathione content and SOD activity did not change significantly. It could be inferred that AsA, flavonoids, POD and CAT play key roles in ROS metabolism during the development of black heart disease in post-harvest pineapple.

    Figures and Tables | References | Related Articles
    Preparation and Antioxidant Activities of Macadamia Nut Peptides by Combined Enzymatic Hydrolysis
    SHUAI Xixiang,ZHANG Ming,MA Feiyue,DU Liqing,LI Qiuhong,TU Xinghao
    2020, 41 (7):  1434-1439.  doi: 10.3969/j.issn.1000-2561.2020.07.021
    Abstract ( 350 )   HTML ( 8 )   PDF (1322KB) ( 262 )  

    In this paper, the macadamia protein peptide were obtained from the macadamia protein prepared by the enzyme mixture treatment. The effects of various factors on the protein hydrolysis degree of macadamia nuts were investigated by the single factor test and orthogonal test. At the same time, the preliminary separation of the protein peptide was carried out by ultrafiltration centrifuge tubes (3, 10, 30 kDa) with different molecular weights. Then, the antioxidant activity of macadamia nut peptide with different molecular weight was evaluated by DPPH scavenging activity. Results showed that order of the factors was as follows: initial pH > enzyme mixture rate > enzyme concentration > hydrolysis duration. The optimal conditions were as follows: enzyme mixture rate (papain protease and neutral protease) 1∶5, enzyme concentration 12 000 U/g, initial pH 9.0, hydrolysis duration 360 min. Under the optimized condition, the hydrolysis degree of macadamia nut protein was 21.88%. It was found that macadamia nut peptide with different molecular weight had antioxidant activities, and the strongest was the 3~10 kDa peptide. And the DPPH free radical scavenging ability reached 80.97%. As the concentration of the protein peptide component increased, its antioxidant activity also increased.

    Figures and Tables | References | Related Articles
    Comparison of Volatile Components and Aroma Characterization in Sichuan Black Tea and Qimen Black Tea
    ZHANG Xiang,WANG Congming,NIE Congning,LI Shunyu,XU Yifan,XIE Anran,DU Xiao
    2020, 41 (7):  1440-1449.  doi: 10.3969/j.issn.1000-2561.2020.07.022
    Abstract ( 389 )   HTML ( 4748 )   PDF (1545KB) ( 857 )  

    In order to determine the differences of the aroma characterization and components in Sichuan Black Tea (CH) and Qimen Black Tea (QH), the black tea in the two regions were sampled as the research objects. The aroma characterization and volatile components of three typical tea samples were analyzed by sensory the analysis method and static headspace-solid phase microextraction / gas chromatography-mass spectrometry (SHS-SPME/GC-MS). The contribution rates were evaluated according to the relative content of each component and relative odour activity value (ROAV). CH1 presented strong fruit, sweet and roasted aroma with moderate flowery aroma, faint woody and fresh aroma coupled with light green aroma. CH2 also showed strong flowery and sweet aroma with moderate fruit, green and roasted aroma added light fresh and woody aroma. QH presented strong sweet and fruit aroma, with other prominent aroma characterization. The ROAV analysis combined with a characterization description of aroma showed that the common main aroma contributors of the three tea samples were linalool and geraniol. CH1 had 2-hexenal, cinene and furfural, with ROAVs of 362.59, 6.74 and 1.05, respectively. CH2 showed the presence of linalool oxide, phenylacetaldehyde, cis-3-hexenol and benzyl alcohol, with ROAVs reached 1472.33, 462.22, 383.92 and 4.42, respectively. QH also showed the presence of linalool, linalool oxide, geraniol, n-hexanal, phenylacetaldehyde, 1-nonanal, cis-3-hexenol and 2-pentylfuran, with all having a ROAVs of more than 100. In addition, 12 kinds of aroma components in three kinds of black tea, including linalool, phenylacetaldehyde, n-hexanal, geraniol, linalool oxide, n-nonanal, 2-pentylfuran, cis-3-hexenol, methyl salicylate, n-heptanal, limonene and phenethyl alcohol may be the material basis of black tea-based aroma.

    Figures and Tables | References | Related Articles
    Extraction and Antioxidant Activity of Polyphenols from Gynura formosana Kitam
    MA Jingfan,LIN Zhemin,LIU Ying,LIU Ximing,CHEN Xuemei
    2020, 41 (7):  1450-1458.  doi: 10.3969/j.issn.1000-2561.2020.07.023
    Abstract ( 274 )   HTML ( 7 )   PDF (8933KB) ( 156 )  

    The extracting technique of polyphenols from Gynura formosana Kitam by supercritical CO2 was optimized and the antioxidant activity in vitro and in vivo was studied to provide a theoretical basis for the development and comprehensive utilization of G. formosana Kitam. Extraction pressure, extraction time, extraction temperature, CO2 flow rate, and the consolvent concentration as single factors, the response surface method was used to optimize the extract conditions based on extraction yield. The antioxidant activity in vitro was established by DPPH and ABTS radicals scavenging rate. The antioxidant activity in vivo was evaluated using the D-galactose aging mice model. Three different doses (150, 300, 600 mg/kg every day) of polyphenols from G. formosana Kitam were given for 30 days. superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) activities and malondialdehyde (MDA) content were determined in mice serum and liver. The best conditions for extracting polyphenols from G. formosana Kitam were extraction pressure 35 MPa, extraction time 2 h, extraction temperature 40 ℃ and CO2 flow rate 20 L/h. The yield under the optimal conditions was 5.32% DPPH and ABTS radicals scavenging rate were improved with the increasing concentration of extraction. Compared to the control group, SOD, GSH-Px and CAT activities were decreased significantly and MDA content was increased significantly in mice serum and liver in the aging model group. Compared to the aging model group, SOD, GSH-Px and CAT activities were increased significantly and MDA content was decreased significantly in mice serum and liver in extract treatment group.

    Figures and Tables | References | Related Articles
    Effect of Microwave Vacuum Drying on Quality Characteristics of Dendrobium officinale
    LIN Hong,WANG Weiwei,ZHENG Baodong,GUO Zebin
    2020, 41 (7):  1459-1468.  doi: 10.3969/j.issn.1000-2561.2020.07.024
    Abstract ( 294 )   HTML ( 6 )   PDF (1938KB) ( 235 )  

    The microwave vacuum drying method was used to dry Dendrobium officinale. The effects of microwave vacuum drying on the quality characteristics of D. officinale were studied by measuring the content of polysaccharides, color, polyphenol oxidase (PPO), water distribution, Composition of amino acids and DPPH? and ?OH scavenging rates of polyphenols. When the microwave intensity was 9 W/g compared with the fresh sample, the dried sample had the highest polysaccharide content of 52.21%. The content of total free amino acids and flavor amino acids of D. officinale was significantly increased after microwave vacuum drying. PPO activity of D. officinale after microwave vacuum drying at microwave intensity of 9 W/g, 12 W/g and 15 W/g was no longer present at the 16th, 12th and 6th minutes respectively, indicating that microwave vacuum drying could inactivate PPO activity of D. officinale in a relatively short time, and higher microwave intensity would lead to shorter time. Non-enzymatic browning in drying process was caused by Maillard reaction. The free water relaxation time T23 and A23 decreased significantly. The free radical scavenging ability of D. officinale showed that the hydroxyl radical scavenging ability was still strong. By observing the microstructure of the sample after drying, the pore structure of the sample was seriously damaged with the increase of microwave power density. The rehydration characteristics of D. officinalis showed that higher microwave intensity resulted in better rehydration characteristics.

    Figures and Tables | References | Related Articles
    Agricultural Ecology & Environmental Protection
    Community Characteristics of Wild Plant Species with Extremely Small Populations Phalaenopsis lobbii
    HUANG Xinyi,LU Zuzheng,BIN Zhenjun,GAN Chunlin,QIN Qian,DING Liqiong
    2020, 41 (7):  1469-1476.  doi: 10.3969/j.issn.1000-2561.2020.07.025
    Abstract ( 287 )   HTML ( 3 )   PDF (9827KB) ( 149 )  

    Phalaenopsis lobbii is a rare species with extremely small populations in China. Field investigation covering habitat survey and quadrangular survey in community 1 in Longhushan Nature Reserve, Guangxi, China and community 2 in small nature reserve of Horsfieldia hainanensis and Camellia impressinervis was conducted to study the community characteristics including habitat characteristics, species composition, community floristic characteristics and the structure. P. lobbii lived in an evergreen broad leaved forest with limestone with an altitude 150-330 meters. The vegetation of the habitat was well preserved. There were a total of 50 species of vascular plants in community 1, which belonging to 45 genera and 32 families. The biodiversity of the community was rich, among which Liliaceae was the dominant families. There were 38 species of vascular plants in community 2, which belonging to 35 genera and 26 families, without dominant families. Tropical Asian and pantropical genera played the dominant status at the generic level in the two communities. The floristic composition of the two communities showed tropical and subtropical transition. Both communities were dominated by the phanerophyte plants, making up 64% of the total species in community 1 and 65.79% in community 2, and lianas accounted for the largest proportion, indicating that canopy density increased and P. lobbii had certain requirements for ambient humidity and illumination. Importance values of herb layer species showed that multiple dominant populations were included in the community. Aglaonema modestum, Pilea boniana and Aspidistra fungilliformis were the dominant species in community 1 and Caryota monostachya, Tectaria subtriphylla, Rhaphidophora decursiva were the dominant species in community 2. P. lobbii was the only one orchid plant and just as an accompanying species in plant communities which attached to the trunk of the trees in the two community. At present, there are few systematic studies on the community structure and conservation of wild plant resources of P. lobbii. Further study is recommended about the germplasm resources and conservation of the plant. Taken measures such as strengthening local protection, combining with ex-situ protection, studying endangered mechanism, introducing species back into the wild by artificial cultivation and propagation to alleviate the endangered situation in the wild, and providing technical support for rational development and utilization.

    Figures and Tables | References | Related Articles
    Evaluation of Landscape Utilization Potential of Traditional Green Manure in Guizhou
    ZHANG Qin,YAO Danjun,WU Xinghong,RAN Bin,ZHANG Aihua,WANG Wenhua,KUANG Shengjian,ZHU Qing,CAO Weidong
    2020, 41 (7):  1477-1483.  doi: 10.3969/j.issn.1000-2561.2020.07.026
    Abstract ( 245 )   HTML ( 3 )   PDF (2731KB) ( 250 )  

    To develop sightseeing agriculture and ecological environment and evaluate the utilization potential of mountain landscapes of traditional green manures in Guizhou, seven traditional green manures, Vicia villosa var., Astragalus sinicus L., Vicia sativa L., Raphanus sativus L., Lathyrus cicera L., Oil-sunflower, Orychophragmus violaceus (L.) O. E. Schulz, were studied. The temporal and spatial distribution characteristics, visual characteristics of flowers and other landscape benefits, as well as the growth characteristics and nutrient benefits of green manure crops were analyzed. The flowering time of O. violaceus (L.) O. E. Schulz was the earliest, followed by R. sativus L., L. cicera L., A. sinicus L., V. villosa var., V. sativa L. Oil-sunflower was summer green manure. Its initial flowering stage was in mid-June and its florescence was 17-43 days. The length of flowering was O. violaceus (L.) O. E. Schulz > R. sativus L. > Oil Sunflower > V. villosa var. > A. sinicus L. > L. cicera L. > V. sativa L. Oil-sunflower, R. sativus L. was 150-200 cm, 75-95 cm high, respectively. O. violaceus (L.) O.E. Schulz, V. villosa var., V. sativa L. was 25-50 cm high. A. sinicus L., L. cicera L. was 15-25 cm high. V. villosa var. had the most flowers, and Oil-sunflower had the largest flower area. V. villosa var. was the largest in the area of a plant. With regard to the goal of sightseeing and conservation, blue-violet O. violaceus (L.) O.E. Schulz could be planted between February to March, purplish red As. sinicus L., white R. sativus L. could be planted between March and April, and purple V. villosa var. could be planted in April, yellow Oil-sunflower could be planted in June and July, which would enrich the color of Guizhou sightseeing agriculture, prolong the sightseeing time and diversify the tourism brand.

    Figures and Tables | References | Related Articles
    Newly Recorded Plants of Angiosperm in Hainan (Ⅲ)
    WANG Qinglong,WANG Maoyuan,YANG Hubiao,YAN Xiaoxia,WANG Zhunian
    2020, 41 (7):  1484-1489.  doi: 10.3969/j.issn.1000-2561.2020.07.027
    Abstract ( 447 )   HTML ( 8 )   PDF (2162KB) ( 278 )  

    Seven species of Angiosperm were newly recorded in Hainan Island. The newly recorded species were Zingiber cochleariforme D. Fang, Crotalaria goreensis Guill. & Perr., Croton bonplandianus Baill., Phyllanthus tenellus Roxb., Mecardonia procumbens (Mill.) Small, Cyperus surinamensis Rottb?ll, and Spartina alterniflora Lois.. All voucher specimens were kept in Herbarium of Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences, Hainan (ATCH).

    Figures and Tables | References | Related Articles
    Variations of Canopy Temperature in a Rubber Plantation in Western Hainan Island and Their Relations with Micrometeorological Factors
    DENG Cong,WU Zhixiang,TAN Zhenghong,LIAO Liguo,CUI Yibin,CHENG Juan,ZHAO Linlin
    2020, 41 (7):  1490-1497.  doi: 10.3969/j.issn.1000-2561.2020.07.028
    Abstract ( 235 )   HTML ( 2 )   PDF (1419KB) ( 253 )  

    Canopy temperature is one of the most important parameters to characterize the physiological, ecological processes and energy balance of plants. In order to investigate the variation of the canopy temperature in tropical forests at different time scales and to preliminarily analyze the relationship between environmental factors and canopy temperature, an infrared temperature sensor was used to measure the canopy temperature of a rubber plantation in Western Hainan Island in 2017. Based on the annual canopy temperature data and synchronous canopy micrometeorological data, the characteristics of canopy temperature (Tc) and air temperature (Ta) of a rubber plantation in dry and wet seasons were analyzed, and the micrometeorological factors were discussed. The daily change of canopy temperature in a rubber plantation was a single-peak curve every month. Compared with Ta, Tc had obvious characteristics of phase forward and intensified change. During the day, the canopy boundary layer was unstable, and the canopy was the heat source of SPAC (Soil-Plant-Atmosphere Continuum), at night, the canopy boundary layer was inversion stratification, which was stable, and the canopy was the cold source of SPAC. The canopy temperature in wet seasons was higher than that in dry seasons. If only Ta was considered, Tc and Ta had a good linear relationship, and the linear equation was Tc= 1.03Ta-0.656. If the micro-meteorological factors such as atmospheric temperature (Ta), net radiation (Rn), relative humidity (RH) and wind speed (V) were taken into account, the multiple correlation coefficients showed that the annual correlation was very significant. Partial correlation coefficients showed that the change of canopy temperature in dry seasons was mainly affected by Ta, Rn and RH, and secondly by V. Wet seasons were mainly affected by Ta and RH, the influence of Rn and V was negligible. The results preliminarily revealed the annual variation of canopy temperature in rubber plantation and its relationship with many micro-meteorological factors, providing a scientific basis for further exploring the change of canopy temperature and its influencing mechanism.

    Figures and Tables | References | Related Articles
    Characteristics of Biochar Prepared from Hainan Typical Feedstocks in Different Temperatures
    ZOU Ganghua,DAI Minjie,ZHAO Fengliang,SHAN Ying
    2020, 41 (7):  1498-1504.  doi: 10.3969/j.issn.1000-2561.2020.07.029
    Abstract ( 280 )   HTML ( 8 )   PDF (1439KB) ( 266 )  

    Material and pyrolysis temperature have important effects on the properties of biochar. Nine typical feedstocks (e.g., coconut shell, banana stem, rubber branch and so on) in Hainan were selected to analyze the properties of the biochar prepared at different temperatures (300, 500 and 700 ℃), as well as the internal correlation. pH, C/H ratio, specific surface area (SSA), and P of the biochar increased as the pyrolysis temperature increased, whereas the yield, hydrogen and sulfur content decreased. Carbon or nitrogen content, electrical conductivity (EC), K, Ca and Mg content, and cation exchange capacity (CEC) of biochar presented different change with the increase of temperature due to varied raw materials. The content of heavy metals in the biochar was not beyond the concentration limited in standards. Carbon content, C/N ratio and P, K, Ca and Mg content in the biochar were all positively correlated with that in raw material (P<0.05). Potassium content in feedstocks had significant effects on pH, EC and CEC of biochar. Considering the properties of yield, carbon content, SSA, CEC and mineral elements, the biochars from mushroom residue, coconut shell and banana pseudostem were better. This conclusion would be helpful for feedstock selection for the biochar production in tropical areas.

    Figures and Tables | References | Related Articles