Table of Content

25 June 2020, Volume 41 Issue 6 Previous Issue    Next Issue

Crop Culture and Nutrition, Genetic BreedingCrop Culture and Nutrition, Genetic Breeding

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Relationship Between Soil Factors, Quality and Yield Formation in Coffea arabica ZHAO Mingzhu,GUO Tieying,MA Guanrun,XIAO Ziwei,BAI Xuehui,ZHOU Hua,SU Linlin 2020, 41 (6):  1065-1075.  doi: 10.3969/j.issn.1000-2561.2020.06.001 Abstract ( 488 )   HTML ( 44 )   PDF (1594KB) ( 457 )   Soil factors play important roles in affecting the quality and yield of Coffea arabica. The purpose of the study was to provide an academic evidence for guiding the scientific fertilization, good quality and high yield, and identifying the primary indexes of quality, yield by investigation the variation of soil factors of C. arabica. The correlation, improved grey relational analysis, path analysis, and multiple linear regression analysis were conducted to identify the primary indexes of C. arabica quality and yield. The results showed that altitude was a key soil determinant of caffeine in C. arabica (-0.296 *), the prime determinant factors of total sugar content were soil organic matter (OM) (0.607**) and available phosphorus (AP) (0.232*), that for crude protein content were soil pH (-0.387**) and OM (0.227*), that for crude ash content was AP (0.334**), that for water-soluble extracts content was altitude (-0.494**), that for fat content was alkalystic nitrogen (AN) (-0.461**), and that for the yield of C. arabica were available potassium (AK) (0.339**) and OM (0.248*). The results would be useful to guiding the screening of soil conditions, reducing the amounts of fertilizer and increasing the fertilizer-use efficiency in order to enhance the suitability and purpose of the excellent germplasm in C. arabica. Figures and Tables | References | Related Articles

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Changes of Agronomic Traits, Yield and Soil Nutrient of Red Soil in Southern China under Different Nitrogen Application Rates LIN Xiaobing,ZHOU Lijun,HUANG Shangshu,ZHONG Yijun,CHENG Yanhong,ZHANG Kun,SUN Yongming,WU Lin 2020, 41 (6):  1076-1083.  doi: 10.3969/j.issn.1000-2561.2020.06.002 Abstract ( 470 )   HTML ( 17 )   PDF (4371KB) ( 297 )   To explore the changes of agronomic traits, yield and soil nutrient of peanut under different nitrogen application rates in dryland of red soil in southern China, a randomized block experiment was conducted in the field. Using high-nitrogen fertilizer as the material, eight treatments including no nitrogen fertilizer (N0), 200% nitrogen application rate (N200%), 150% nitrogen application rate (N150%), 100% nitrogen application rate (N100%), 80% nitrogen application rate (N80%), 60% nitrogen application rate (N60%), 40% nitrogen application rate (N40%) and 20% nitrogen application rate (N20%) were set. The results showed that compared with N0, the application of nitrogen fertilizer could increase the yield of peanut pods, and the yield increase of peanut pods was 12.94%-24.62%. Pods yield, pods weight per plant and plump rate of peanut increased with the increase of nitrogen application rate. Branch number per plant and 100-kernel weight did not change significantly with nitrogen application rates. Plant height and 100-pod weight were the best in N80%. The soil alkaline nitrogen increased with the increase of nitrogen application rate. Correlation analysis showed that there was a significant positive correlation between pods yield of peanuts and plump rate, organic matter, alkaline nitrogen. There was a significant positive correlation between soil alkaline nitrogen and plump rate, organic matter, but a significant negative correlation with pH. Principal component analysis showed that the first principal component trait, the yield factor, such as fruit yield, pods weight per plant and fruit weight had an important effect on peanut growth. Path analysis showed that the path-coefficient of 100-pod weight and plump rate was large, and the two traits should be emphasized in increasing the yield of peanut fruit. In summary, pod yield, plant height, pods weight per plant, 100-pod weight and 100-kernel weight of N80% were the best in peanut yield, agronomic traits and cost. Figures and Tables | References | Related Articles

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Effects of Different Hormone Types, Concentrations and Soaking Time on Cutting Rooting of Xanthostemon chrysanthus ZHANG Peijian,GAO Liqiong,SHANG Xiuhua 2020, 41 (6):  1084-1091.  doi: 10.3969/j.issn.1000-2561.2020.06.003 Abstract ( 415 )   HTML ( 12 )   PDF (1629KB) ( 430 )   Taking semi-lignified branches of Xanthostemon chrysanthus as the cutting and loess+sand (1∶1) as thesubstrates, the effects of different hormone types, concentrations and soaking time on the rooting of X. chrysanthus cuttings was studied by the orthogonal experiment. The most suitable treatment for the rooting was obtained, which would providea theoretical basis and technical support for its cutting propagation. The rooting was mainly in the cortical tissue. The survival rate of cuttings was over 90%. Hormone concentration was the most important factor affecting the rooting, followed by hormone types, and soaking time had the least effect. Range analysis showed that the most suitable factor combination for cutting rooting rate was A2B2C3 (500 mg/L IBA soaked for 2 minutes) or A2B3C1 (200 mg/L IBA soaked for 30 minutes). The most suitable combination for cutting rooting number was A1B1C1 (1000 mg/L NAA soaked for 30 minutes), and A3B3C2 (200 mg/L “Gentaiyang” rooting agent soaked for 10 minutes) was the most suitable for cutting rooting length, the most suitable combination for longest rooting length was A2B1C2 (1000 mg/L IBA soaked for 10 minutes), and the most suitable combination for cutting rooting index was A1B1C1 (1000 mg/L NAA soaked for 30 minutes). The results of principal component analysis combined with range analysis of rooting effect index showed that A1B1C1 (1000 mg/L NAA soaked for 30 minutes) and A1B2C2 (500 mg/L NAA soaked for 10 minutes) were the better combination for survival and rooting. In a word, X. chrysanthus was a plant relatively easy to be used as cuttings. The experimental results could provide a reference for cutting propagation of X. chrysanthus in future production. Figures and Tables | References | Related Articles

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The Effect of Aluminum Stress on Nutrient Absorption in Cynodon dactylon Accessions HUANG Chunqiong,CHEN Zhen,CUI Rongjing,LIU Guodao,WANG Wenqiang 2020, 41 (6):  1092-1099.  doi: 10.3969/j.issn.1000-2561.2020.06.004 Abstract ( 281 )   HTML ( 9 )   PDF (1296KB) ( 240 )   The absorption, transportation and distribution of nutrients in plants under aluminum stress are the basis of Al toxicity. In this study, the effects of aluminum stress on the absorption and transportation of the aluminum, total nitrogen, total phosphorus, potassium, calcium were studied in Cynodon dactylon by the water culture method. The results showed that the Al content in C. dactylon was increased under aluminum stress, and the Al content mainly manilyaccumulated in roots. The absorption of the total nitrogen, total phosphorus, potassium, calcium under aluminum stress was inhibited in C. dactylon. The content of N, P, Ca and K of the overground part decreased averagely by 25.00%, 33.67%, 29.29% and 25.82%, the content of N, P, Ca and K of roots decreased averagely by 28.69%, 14.58%, 26.28%, 27.07%. The results revealed that the P and K were mainly distributed in roots, and those transported to the overground part were decreased. More Ca was transported to the overground part under aluminum stress. Figures and Tables | References | Related Articles

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Effect of Bamboo Sawdust Substrate and Strain Planting Density to Yield and Nutritional Quality of Dictyophora echinovolvata PENG Chao,AI Wensheng,XIE Yunfan,SHI Yanfei,ZHONG Yi,LI Nan 2020, 41 (6):  1100-1107.  doi: 10.3969/j.issn.1000-2561.2020.06.005 Abstract ( 351 )   HTML ( 15 )   PDF (1416KB) ( 276 )   The effect of the ratio of bamboo sawdust substrate and strain planting density to the yield and nutritional quality of Dictyophora echinovolvata was discussed by the orthogonal design to screen the optimal combination and to provide a scientific technical support for D. echinovolvata cultivation. The results showed that the average fresh yield was 3.51 kg/m2, and the percentage of crude protein, crude fiber and total sugar was 18.78%, 21.19% and 37.79%, respectively. There were highly significant differences of yield, crude protein, total sugar among treatment combinations (P<0.01), and there was significant difference of crude fiber (P<0.05). The yieldwassignificantly affected by bamboo sawdust substrate weight and planting density, while the nutrient composition was almost not influenced by bamboo sawdust substrate weight and planting density. The yield of the strain planting density 600 g/m2was 4.54 kg/m2, which was significantly higher than those of the strain planting density 400 g/m2 and 800 g/m2. The yield of 16 kg/m2sawdust substrate was 3.95 kg/m2, which was higher than those of 8.0 kg/m2 and 12 kg/m2sawdust substrate. Crude protein, crude fiber and total sugar were highly affected by the interaction of the ratio of bamboo sawdust substrate and strain planting density. Range analysis suggested that planting density had higher effect than sawdust substrate to yield, protein and crude fiber, and there was an opposite effect on total sugar content. The range of expenditure/income ratio was (1∶3.77) to (1∶9.32),of which 16 kg bamboo sawdust substrate with cultivated 600 g/m2 had the highest output value, 54.9 yuan per square meter, with a corresponding expenditure/income ratio 1∶6.62. The mass investment of sawdust substrate and strain planting density had no positive correlation to output value. It was suggested that although the nutrient composition would not be changed by the ratio of bamboo sawdust substrate and strain planting density, an optimized combination of the two would have positive effect both in the yield and expenditure/income ratio of D. echinovolvata. Figures and Tables | References | Related Articles

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Genetic Diversity Analysis Based on Main Phenotypic Characteristics of Erianthus arundinaceum Germplasm from Different Regions WANG Chunfang,YU Xinghua,WANG Xianhong,YANG Qinghui 2020, 41 (6):  1108-1116.  doi: 10.3969/j.issn.1000-2561.2020.06.006 Abstract ( 355 )   HTML ( 14 )   PDF (1690KB) ( 279 )   The germplasm resource, genetic diversity including plant height, stem diameter, internode length, leaf length, leaf width and brix of 76 clones of E. arundinaceum, which were collected from different regions was analyzed. The average coefficient of variation of the six phenotypic traits was 14.6%-53.4%, the coefficient of variation of plant height and internode length was 53.4% and 37.7%, respectively, and the coefficient of variation of brix and leaf length was 19.1% and 14.6%, correspondingly. There was a significant positive correlation among plant height, stem diameter, leaf width, leaf length and internode length, among which the correlation coefficient between plant height and internode length was 0.818. Meanwhile, brix was negatively correlated with plant height and internode length, with correlation coefficients of -0.232 and -0.263, respectively. Principal component analysis showed that the cumulative contribution rate of the first two principal components was 72.58%, of which the contribution rate of the first principal component was 51.21%, and that of the second principal component was 21.37%. By cluster analysis, 76 clones were divided into eight groups and the comprehensive characters of V and VI groups were the best. The two groups are excellent E. arundinaceum germplasm resources, which could be excavated and utilized in sugarcane breeding program. Figures and Tables | References | Related Articles

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Variation and Probability Grading of Main Quantitative Traits of Phalaenopsis Germplasm Resources ZHONG Haifeng,CHEN Jianfeng,CHEN Yuhua,QIU Sixin,HUANG Minling 2020, 41 (6):  1117-1123.  doi: 10.3969/j.issn.1000-2561.2020.06.007 Abstract ( 360 )   HTML ( 12 )   PDF (1340KB) ( 258 )   The variation, normality test and probability grading analysis of 24 main quantitative traits were carried out, using 53 Phalaenopsis germplasm resources as the research materials. The coefficient of interspecific variation of the traits varied from 8.22% to 45.31%. Among them, the coefficient of variation of the flower number was the biggest, while the length of gynostemium was the least. Meanwhile, the coefficient of intraspecific variation of the traits varied from 5.07% to 22.50%. The coefficient of variation of inflorescence length was the biggest, and the flower width was the least. The Sig value of 23 quantitative traits, such as plant size and leaf length, was more than 0.05 by K-S test, which was in accordance with normal distribution, and the number of inflorescence showed skewed distribution according to chi-square test. All the quantitative traits examined were in accordance with normal distribution. The 24 quantitative traits could be divided into five grades. Four points (X-1.2818S), (X-0.5246S), (X+0.5246S) and (X+1.2818S) are used uniformly, so that the probability of the trait value falling into 1-5 grades is 10%, 20%, 40%, 20% and 10%, respectively. Figures and Tables | References | Related Articles

Phytophysiology and Biochemistry

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Effects of Exogenous ABA on Physiology of Four New Oil Palm Varieties under Cold Stress LIU Yanju,ZHOU Lixia,CAO Hongxing 2020, 41 (6):  1124-1131.  doi: 10.3969/j.issn.1000-2561.2020.06.008 Abstract ( 438 )   HTML ( 17 )   PDF (1362KB) ( 464 )   In order to provide theoretical basis for improving cold resistance of different oil palm varieties, the present experiment was conducted to investigate the expression characteristics of ABA synthase gene NCED3 of different oil palm varieties under cold stress and the growth and physiology effects of different ABA concentrations on cold resistance of different oil palm varieties. The new oil palm varieties Ni, C×N, B×E and D×N were used as the materials, treated with low temperature stress (15 ℃, 10 ℃, 5 ℃, 5 d). The expression characteristics of NCED3 in the seedlings were detected by real-time quantitative PCR (qPCR). Then, different concentrations of ABA (50-300 μmol/L ABA) were applied to the seedlings under 10 ℃, and the physiological indexes were determined, including soluble protein content, soluble sugar content, proline content, H2O2 content, MDA content, SOD and POD activity. Cold stress could trigger the overexpression of ABA synthase gene NCED3 in the seedlings. The application of 50-300 μmol/L ABA decreased the plasma membrane permeability and SOD activity of the seedlings, inhibited the increase of MDA and H2O2 levels, so the membrance lipid peroxidation caused by cold stress was relieved, soluble protein, soluble sugar content and POD activity were increased, and thus improved cold resistance of the seedlings. B×E had strong cold tolerance. Figures and Tables | References | Related Articles

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Morphological and Physiological Characteristics of Areca catechu L. Seedlings under Different Soil Moisture Contents LI Han,YANG Fusun,LI Changzhen,CHEN Qi,ZHANG Han,JIU Fengfeng,CHEN Caizhi 2020, 41 (6):  1132-1137.  doi: 10.3969/j.issn.1000-2561.2020.06.009 Abstract ( 452 )   HTML ( 16 )   PDF (1272KB) ( 324 )   Five water gradients, T1: (30±5)%, T2: (45±5)%, T3: (60±5)%, T4: (75±5)%, T5: (90±5)%, were used to clarify the relationship between soil moisture and areca seedlings (Areca catechu L. seedling). The morphology, photosynthetic characteristics, chlorophyll content and root activity of the seedlings were determined. The result showed that the relative soil water content of about 55%-65% could increase the plant height, stem diameter, leaf area and leaf length. The plant height and stem diameter ratio of the seedlings increased by 26.89% and 19.89% respectively under 25%-35% relative soil water content. And the net photosynthetic rate and transpiration rate of the seedlings reached significant levels. When the relative soil water content was more than 55%-65%, the cracked leaves of the seedlings increased, but the chlorophyll content decreased gradually. When the relative soil water content was less than 55%, the chlorophyll content and root activity of the seedlings decreased. With the decrease of soil relative water content, the root-shoot ratio of the seedlings increased. The chlorophyll content of the seedlings reached the lowest value of 11.16 mg/g under 30% relative soil water content, but the water use efficiency was higher than that in other treatments. The leaves of the seedlings were yellow, and the plants were short, and the root activity was also small. In conclusion, when the relative water content in soil was 55%-65%, it was beneficial to the growth of areca seedlings. Figures and Tables | References | Related Articles

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Effects of Different Canopy Density on Growth and Photosynthetic Characteristics of Camellia nitidissima and Camellia Japonica in Illicium verum Forest LYU Qinyang,WEI Xiandong,CHEN Xin,LU Jingjing,TAO Zhihua,WANG Linghui 2020, 41 (6):  1138-1144.  doi: 10.3969/j.issn.1000-2561.2020.06.010 Abstract ( 350 )   HTML ( 10 )   PDF (1480KB) ( 301 )   The influences on the growth and photosynthetic characteristics of Camellia nitidissima and Camellia japonica were studied under full illumination (CK) and Illicium verum forest canopy density at 0.9, 0.7 and 0.5, respectively. The degree of canopy density had a significant effect on the growth index of C. nitidissima and C. japonica, except that it had no significant effect on the leaf width of C. nitidissima. Compared with total illumination, the plant height, ground diameter and biomass of C. nitidissima and C. japonica increased at a canopy density of 0.5, 0.7, and 0.9, and the increase of C. nitidissima was greater than that of C. japonica. The specific leaf weight of both plants decreased first and then increased with the increase of canopy density, and was the highest under full illumination. The leaf length and leaf width of the two plants were the smallest under full illumination, while the leaf thickness was the largest under full illumination. The leaf area and specific leaf area increased first and then decreased with the increase of canopy density. The canopy density was the largest under 0.7 and the smallest under full illumination. The Pn of C. nitidissima was significantly higher than that of other treatments under the canopy density degree of 0.7 and the canopy density of 0.5, and both increased with the increase of effective photosynthetic radiation intensity, and finally stabilized. The canopy density had a significant effect on the quantum efficiency (AQY), maximum net photosynthetic (Pmax), light saturation point (LSP), light compensation point (LCP) and dark respiration rate (Rd) of C. nitidissima and C. japonica. With the increase of canopy density, AQY, Pmax and LSP of C. nitidissima and C. japonica increased first and then decreased. C. nitidissima was the largest in canopy density 0.7, and C. japonica was the largest in canopy density 0.5. LCP of the two plants was the largest under full illumination. Rd of C. nitidissima was the largest under full illumination, and Rd of C. japonica was the largest under the canopy density degree of 0.5. According to comprehensive analysis, C. nitidissima and C. japonica had certain tolerance to darkness and had certain adaptability to low light environment. They were suitable for growth under the environment of canopy density of 0.5-0.7, but intense light was not conducive to the two plants. Figures and Tables | References | Related Articles

Biotechnology and Tissue Culture

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Bioinformatics Analysis of Dehydrogenase Genes Family from the Blumea balsamifera (L.) DC. BAI Lin,GUAN Lingliang,ZHA Ying,YU Fulai,WANG Kai,XIE Xiaoli,PANG Yuxin,CHEN Songbi 2020, 41 (6):  1145-1153.  doi: 10.3969/j.issn.1000-2561.2020.06.011 Abstract ( 370 )   HTML ( 8 )   PDF (2442KB) ( 296 )   Four dehydrogenase genes, named as BbADH1, BbADH2, BbADH3, BbADH4, were cloned from Blumea balsamifera (L.) DC. by the reverse transcription polymerase chain reaction approach (RT-PCR) and rapid amplification of cDNA ends (RACE) andanalyzed by bioinformatics. The open reading frames of the four dehydrogenase sequences were all around 900 bp, and the isoelectric point (pI) of the proteins was 5.0-9.0. The most abundant amino acid of BbADH was leucine (Leu), and the least was tryptophan (Try). BbADH showed obvious hydrophobic and hydrophilic regions, no signal peptide at the N-terminus, and no transmembrane region. BbADH from B. balsamifera (L.) DC showed a high similarity with BbADH from other plants, containing the characteristic functional domain of dehydrogenase. Phylogenetic analysis indicated that BbADH1 and BbADH3 were in the same branch and were closely related to PeADH of Populus euphratica Oliv., while BbADH4 and BbADH2 were in different branches, and were closely related to VvADH of Vitis vinifera and NtADH of Nicotiana tabacum, respectively. Figures and Tables | References | Related Articles

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DNA Amount Estimation and Genome Survey of Sweetpotato Wild Relatives Ipomoea cordatotriloba WANG Yao,DENG Yitong,DAI Xibin,ZHANG An,CAO Qinghe,CHEN Yanli 2020, 41 (6):  1154-1159.  doi: 10.3969/j.issn.1000-2561.2020.06.012 Abstract ( 347 )   HTML ( 13 )   PDF (2196KB) ( 333 )   DNA content of sweetpotato wild relatives Ipomoea cordatotriloba was determinated by flow cytometry using soybean Williams 82 as the internal reference in this study. The ploidy was determined by chromosome counting. In order to verify the reliability of the results, the next-generation sequencing was used to further test and verify. It was a diploid species with base number was 15. The genome size was (539.69±13.76) Mb by the flow cytometry analysis. The C-value determined by sequencing was similar to the results of flow cytometry. Furthermore, the genomic heterozygosity rate, repeat sequence ratio and GC content was 0.40%, 57.93% and 38.10%, respectively. The above results would lay the foundation for the whole genome sequencing and assemble of this species, and provide references for the utilization of sweetpotato relatives. Figures and Tables | References | Related Articles

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Reference Genes Selection for Quantitative Real-time PCR in Antrodia cinnamomea Mycelium of Different Development Stages LI Jing,WANG Zehui,CHEN Li,LIU Yanling,XIA Shuning,LIN Zhanxi 2020, 41 (6):  1160-1166.  doi: 10.3969/j.issn.1000-2561.2020.06.013 Abstract ( 311 )   HTML ( 11 )   PDF (3067KB) ( 279 )   Quantitative Real-time PCR (qRT-PCR) technology is widely used in the analysis of gene expression because of its high sensit-ivity, high accuracy and high specificity. Therefore, it is important to select appropriate reference genes to measure the expression and accuracy of the sample. In this study, the expressions of 18 candidate internal reference genes of Actin, TPK, Floxuridine, CAP-Gly, α-Amylase, Phosphatase, HA2- helicase and MAGT1 were detected by qRT-PCR with A. cinnamomea Mycelium under 7, 21 and 35 d liquid fermentation time. The stability of the internal reference genes were analyzed using softwares of geNorm, NormFinder and BestKeeper. Floxuridine/ HA2-helicase, TPK, CAP-Gly genes were found more stable with geNorm. TPK, CAP-Gly, Floxuridine, HA2-helicase were found more stable with NormFinder. HA2-helicase was found to be best expressed with BestKeeper, followed by TPK and MAGT1. The comprehensive analysis showed that TPK and HA2-helicase had the best stability and were more suitable as the internal reference genes for A. camphorata. The results of this study would have a practical guiding role in the analysis of the selection of internal reference genes in the gene expression of A. cinnamomea by qRT-PCR. Figures and Tables | References | Related Articles

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Enzyme Activity Characteristics and Expression of Cu/Zn-SOD Gene in Tea Flowers WANG Mengxin,WU Guohuo,CUI Lin,HAN Baoyu 2020, 41 (6):  1167-1173.  doi: 10.3969/j.issn.1000-2561.2020.06.014 Abstract ( 631 )   HTML ( 12 )   PDF (2333KB) ( 373 )   In order to study the expression characteristics of Cu/Zn-SOD gene in the flowers within different developmental stages and various cultivars of tea plant flowers, and to discuss the correlationship between the expression of Cu/Zn-SOD gene and its enzyme activity, four developmental stages of cultivar ‘Longjing 43’ tea flower and 15 tea plant cultivars of fresh flowers were studied. The expression of three Cu/Zn-SOD genes was quantitatively analyzed by real-time fluorescent quantitative PCR techniques, and the enzyme activity of the three Cu/Zn-SOD was also determined simultaneously. The lowest Cu/Zn-SOD enzyme specific activity was found in the fourth stage, and the difference was significant when compared with the other developmental stages. The specific activity of Cu/Zn-SOD enzyme in different cultivars of tea flowers was significantly different. The Cu/Zn-SOD enzyme specific activity of ‘Zijuan’ tea flower was the highest, followed by ‘Huangjinya’ and ‘Baiye 1’. The activity of Cu/Zn-SOD enzyme of ‘Huangguanyin’ tea flower was the lowest. The expression level of Cu/Zn-SOD differed among the developmental stages, and the expression of cytoplasmic Cu/Zn-SOD1 gene was much higher than those of chloroplast type Cu/Zn-SOD2 and peroxisome Cu/Zn-SOD3. The expression of Cu/Zn-SOD in different cultivars was significantly different. Cu/Zn-SOD1 had the highest expression in cultivar ‘Huangmudan’ tea flower, Cu/Zn-SOD2 gene had the highest expression in cultivars ‘Baiye 1’ and ‘Huangguanyin’ tea flowers, and Cu/Zn-SOD3 gene had the highest expression in cultivar ‘Zijaun’ tea flowers. The result of correlation analysis showed that the specific activity of Cu/Zn-SOD had no correlation with Cu/Zn-SOD gene expression in different developmental stages of ‘Longjing 43’ tea flowers, but had considerable correlation with Cu/Zn-SOD3 gene expression in different tea cultivars. In this study, both tea cultivars and suitable plucking stage with high Cu/Zn-SOD activity were preliminarily expounded, which would provide references for the further research on SOD. Figures and Tables | References | Related Articles

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Optimization of Chromosome Sectioning and Karyotype Analysis of Moringa oleifera CHEN Yingying,GUAN Jinyan,TAN Jiana,LUO Jianpiao,HUANG Haiying,WEN Mingfu,LUO Qingwen 2020, 41 (6):  1174-1178.  doi: 10.3969/j.issn.1000-2561.2020.06.015 Abstract ( 425 )   HTML ( 26 )   PDF (1650KB) ( 390 )   Chromosome mounting technique was optimized to explore the chromosome karyotype of Moringa oleifera, to provide important cytological evidences for the study of the evolution, evolutionary characteristics and genetic regularity of camphor plants. The effects of different sampling position, pretreatment methods and enzymatic hydrolysis time on the production of M. oleifera were discussed by the enzymatic dissociation wall low permeability method, microscope observation and photography. The observation showed that the best sampling position was the tips of new branches. Samples pretreated in p-dichlorobenzene for 2 h, dissociated in 4% cellulase and 5% pectinase for 4 h could achieve the optimal experimental results. Karyotype analysis showed that the chromosome number was 28, and the karyotype formula was 2n=2x=2n=28m. The results demonstrated that the asymmetry indexes was 60.29%, and the karyotype was 1B type, suggesting that M. oleifera was possibly relatively primitive in the evolution. Figures and Tables | References | Related Articles

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Tissue Culture and Rapid Propagation of Dendrobium Hibiki MO Yuanqi,LI Hanwen,JIANG Nan,ZHENG Feng,FANG Lin,LI Lin,ZHOU Yiqing,WU Kunlin,ZENG Songjun 2020, 41 (6):  1179-1188.  doi: 10.3969/j.issn.1000-2561.2020.06.016 Abstract ( 483 )   HTML ( 17 )   PDF (1713KB) ( 544 )   The young pseudobulbs of Dendrobium Hibiki were taken as the explants for tissue culture and rapid propagation. The results showed that the success rate of explants disinfection reached 92.50% when treating the explants with proper disinfection methodsby 75% alcohol and 0.1% HgCl2. The modified MS supplemented with 3 mg/L 6-BA and 0.5 mg/L NAA was the most suitable medium for axillary bud induction, in which the induction rate was 91.90%. MS supplemented with 5.0 mg/L 6-BA and 0.5 mg/L NAA was the most suitable medium for the multiplication of clustered shoots, in which the multiplication coefficient was 2.77. 1/2 MS supplemented with 0.5 mg/L IBA, 1.5 g/L activated carbon, 30 g/L sucrose and 100 g/L potato homogenate was the most suitable medium for the rooting and growth, the rooting rate was 100% and growth status of the plantlets was the best. On the mixture of Zhijing stone: coconut husk=1∶1 (V∶V), the plantlets transplanted grew fastly and the survival percentage was 95.56%. Figures and Tables | References | Related Articles

Crop Pests, Diseases and Their Control, Environmental Protection

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Investigation and Preliminary Study of Biological Characteristic of Parasitic Wasps of Spodoptera frugiperda in Hainan TANG Jihong,LYU Baoqian,LU Hui,JI Xuncong,YANG Puyun,SU Hao,CAI Bo 2020, 41 (6):  1189-1195.  doi: 10.3969/j.issn.1000-2561.2020.06.017 Abstract ( 753 )   HTML ( 22 )   PDF (1838KB) ( 612 )   Hainan province is one of the invasion areas of Spodoptera frugiperda in China. In order to grasp the occurrence and prevention and control of S. frugiperda in Hainan, from April to July 2019, experts from Environment and Plant Protection Institute of the Chinese Academy of Tropical Agricultural Sciences conducted field investigations in Hainan province on the natural enemies of S. frugiperda in the main corn-growing areas of 18 cities or counties. In this paper, the parasitic egg mass, larvae and pupa collected in the investigation areas were placed under laboratory conditions for observation. Five species of parasitic wasp were found, among which the egg parasitoid was Telenomus remus Nixon and Trichogramma chilonis Ishii, and the larvae parasitoid was Microplitis pallidipes Szepligeti, and the pupa parasitoid was Tetrastichus howardi Olliff, and the egg-larva parasitoid was Chelonus formosanus Sonan.The main identifying characteristics and basic biological characteristics of the five parasitoids were reported. The natural control effect of the five parasitoids on the alien invasive pest was preliminarily made clear. Mastering the species of natural enemies of S. frugiperda in Hainan has important value for screening the natural enemies for controlling S. frugiperda. Figures and Tables | References | Related Articles

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Trapping Effects of Different (S)-(-)-ipsenol Carrier Lures on Rubber Bark Beetles LIANG Xiao,CHEN Qing,WU Chunling,CHEN Qian,ZHANG Zhe,FAN Dongzhe,DOU Hongshuang 2020, 41 (6):  1196-1201.  doi: 10.3969/j.issn.1000-2561.2020.06.018 Abstract ( 298 )   HTML ( 7 )   PDF (1318KB) ( 343 )   To effectively develop a safe and efficient technique by using (S)-(-)-ipsenol lures in trapping rubber bark beetles, the effects of different (S)-(-)-ipsenol carrier lures were systematically studied. The results indicated that the self-made sponge lure and non-woven lure had the best trapping effects on rubber bark beetles, the average number of trapped adults was 69.16 and 66.22 in a single trap per day, respectively. Besides, the trapping effects gradually increased first and reached the peak on the 30th day, then gradually decreased to a significant level after 60 days, and the average number of trapped adults was 75.22-120.45 and 70.69-112.22 per day during 60 days. The tank lure also had a good trapping effects on rubber bark beetles, the average number of trapped adults was 24.85 per day, and the trapping effects gradually increased first and reached the peak on the 10th day, then gradually decreased to a significant level after 30 days, the average number of trapped adults was 48.53-64.66 per day during 30 days. The above three lures had particularly significant trapping effects on Xyleborus perforans and X. aquilus, which seriously damaged rubber trees, the percentage of the number of X. perforans and X. aquilus to the total trapped beetles was 48.36% and 47.89%, 46.89% and 40.48%, and 40.45% and 40.24%, respectively. The trapping effects of starch granular slow-release lure and cyclodextrin slow-release lure show insignificant difference, the average trapped adults per day were all below 10. The results above illustrated that the self-made sponge lure, non-woven lure and ampoule-type lure of (S)-(-)-ipsenol could be widely used for the effective green monitoring and control of rubber beetles, moreover, the field validity period of the three lures was 60 d, 60 d and 30 d, respectively. Figures and Tables | References | Related Articles

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Sequence Characteristics of Laccase Gene Cglac3 and Its Expression in Two Infection-Related Gene Mutants from Colletotrichum gloeosporioides on Mango ZHONG Changkai,XIAO Chunli,ZHANG He,PU Jinji,WU Qiuyu,LIU Yanli,LIU Xiaomei 2020, 41 (6):  1202-1207.  doi: 10.3969/j.issn.1000-2561.2020.06.019 Abstract ( 357 )   HTML ( 6 )   PDF (2991KB) ( 290 )   In this experiment, a laccase gene Cglac3 was cloned by homologously from Colletotrichum gloeosporioides, which is the fungal pathogen of mango anthracnose, and its expressions during infection process, in laccase gene Cglac1 and exoglucanase gene CgCBH1 deletion knockout mutants, were comparatively analyzed using real-time fluorescent quantitative PCR. Cglac3 was 1842 bp in size with three introns of 56, 51 and 58 bp respectively. The open reading frame of Cglac3 encoded 558 amino acids with a protein molecular weight of 61.38 kDa and an isoelectric point (PI) of 4.50. Cglac3 was highly expressed at 6 h after inoculation when the fungal spores were germing and forming appressoria, increased rapidly at 12 h after inoculation when the fugus were invading. Since then, the expresson of Cglac3 fluctuated during hyphal expansion and leaf necrosis, but both were much higher than the expression level at 0 h. It suggested that Cglac3 played an important role during C. gloeosporioides infection, might be a key virulent factor. Compared with the wild type, the expression of Cglac3 decreased by 74% in the C. gloeosporioides ΔLAC1 mutant, and decreased by 56% in the ΔCgCBH1 mutant. Interestingly, the expression of LAC1 was also decreased by 68% in the ΔCgCBH1 mutant, consistent with the trend of Cglac3 expression, indicating that LAC1 affected the expression of Cglac3, and CgCBH1 affected both the expressions of Cglac3 and LAC1. Figures and Tables | References | Related Articles

Agricultural Product Processing, Preservation, Storage, Analysis and Detection

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Influence of Different Exogenous Fermentable Sugars and Amino Acids on Flavor and Sensory Quality of Coffee Pulp Wine HU Rongsuo,GAN Xiaohong,DONG Wenjiang,LONG Yuzhou,ZONG Ying,CHU Zhong 2020, 41 (6):  1208-1218.  doi: 10.3969/j.issn.1000-2561.2020.6.020 Abstract ( 471 )   HTML ( 8 )   PDF (2270KB) ( 278 )   To explore the effect of coffee pulp wine flavor and sensory quality via different exogenous additives, coffee pulp wine was made by coffee pulp added fermentable sugars (glucose, fructose, maltose and sucrose) and fermentable amino acids (glutamic and arginine) respectively, and coffee pulp wine flavor and sensory quality on exogenous additives effects was detected by headspace solid phase micro extraction gas chromatography mass spectrometry (HS-SPME-GC/MS) and human sensory analysis. The results showed that a total of 9 categories of 75 flavor components was detected and the main compounds were esters and alcohols. Fermentable sugars could increase the alcohol contents of coffee pulp wine (23.99%-121.24%) significantly, and amino acids could also increase the esters contents (25.77%-28.18%), while the esters contents of fermented sugars were significantly reduced (10.81%-69.94%). The homogeneity of variance was tested at P=0.206>0.05, there was no significant difference in flavor components at the level of α=0.05, meanwhile it indicated that there was no significant difference between the samples by tukey post-hoc tests on one-way analysis of variance [P=(0.371-0.989)>0.05], nevertheless principal component analysis (PCA, PC1: 96.01%, PC2: 3.13%) could completely distinguish them. The results of sensory evaluation with fuzzy mathematics method showed that the coffee pulp wine brewed with arginine added had the highest comprehensive score (92.40), which was more suitable for people's taste, and had excellent overall style and preferable coordination, followed by glutamic added coffee pulp wine (80.80). The comprehensive score of fructose and sucrose was the same (78.20), and that of maltose was the lowest (74.20). In summary, amino acids and fermented sugars also could improve the flavor and taste of coffee pulp wines, while the effect of adding fermented sugar was not as good as that of amino acids. Figures and Tables | References | Related Articles

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Effect of Ultrafine Grinding on Physicochemical Properties, Structure and Adsorption Capacity of Coffee Peel LUO Bailing,LIU Dunhua,DONG Wenjiang,HU Rongsuo,LONG Yuzhou,CHEN Zhihua,JIANG Kuaile 2020, 41 (6):  1219-1226.  doi: 10.3969/j.issn.1000-2561.2020.06.021 Abstract ( 463 )   HTML ( 8 )   PDF (2315KB) ( 315 )   Coffee peel powder with different particle sizes was obtained by the traditional pulverization and ultrafine pulverization. By measuring the water holding capacity, swelling capacity, oil holding capacity, solubility and cation exchange capacity of the powders, it showed that the physical properties of the powders were improved with the decrease of particle sizes, among them swelling and solubility were significantly increased from 3.86 mL/g to 6.14 mL/g and 13.23% to 44.50% respectively. By measuring the absorption properties of the powders, it showed that with the decrease of the particle size the adsorption capacity of the powders were enhanced, and the difference between the ultrafine powder and traditional powder was significant. The adsorption quantity of the ultrafine powder to glucose, cholesterol and nitrite was 42.42 mg/g, 29.34 mg/g and 224.56 μg/g respectively, and the adsorption rates was 63.04%, 67.38% and 75.91% respectively. Scanning electron microscopy and Fourier transform infrared spectroscopy results showed that ultrafine pulverization could significantly reduce the powder particle size but had no significant change on the powder structure. The results of this study indicate that ultrafine pulverization can impart better processing and functional properties to coffee peels. The next step can be considered as a new food processing ingredient resource to improve the utilization value of coffee by-products. Figures and Tables | References | Related Articles

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Analysis of Volatile Compounds in Ripening Bananas by Heat Treatment Based on Gas Chromatography-ion Mobility Spectrometry WANG Haibo,DENG Baozhong,WU Rongrong,SHEN Linger,GUO Jiayi,REN Fang 2020, 41 (6):  1227-1233.  doi: 10.3969/j.issn.1000-2561.2020.06.022 Abstract ( 349 )   HTML ( 8 )   PDF (3727KB) ( 278 )   In this study, banana fruits were used as the experimental materials. Banana fruits were treated by heat shock, low temperature and ripening. The volatile substances of the banana fruits were detected by gas chromatography-ion mobility spectrometry. The effects of heat treatment on the volatile substances of ripening banana fruits were studied. The results showed that compared with the control group, the contents of furfuryl alcohol, benzaldehyde, 4-methylphenol, ethyl hexanoate, dimethyldioxanone, 1-pentanol, hexan-2-one, 3-methylbutanoic acid, 2-methoxyphenol, 2-hexanol and ethyl butanoate were significantly decreased in both treatments at 7 ℃ 6 d +ripening for 3 d and H+7 ℃ 6 d +ripening for 3 d. On the contrary, the contents of 1-propanol, propyl acetate, pentan-2,3-dione, dimethyl disulfide, 2,3-butanediol, methyl pyrazine, ethyl 3-methylbutanoate, alpha-pinene, 1-octene-3-ol, diethylene glycol dimethyl ether, E-2-octenal, E, Z-2,6-nonadienal, cis-3-hexenol, octanic acid and heptan-2-one were significantly increased at the two treatment. In addition, the content of hydroxyacetone, 3-methyl-3-buten-1-ol, 3-methyl-2-butanol and other components were significantly increased by H+7 ℃ 6 d +3 d ripening treatment. Compared with the treatment of 7 ℃ 6 d+3 d ripening, the treatment of H+7 ℃ 6 d +3 d ripening significantly reduced the contents of triethylamine, phenol, 2-pentanone, 2-pentyl furan, decanal, E-2-octenal, methional, 2-hexanol, 2,3,5-trimethylpyrazine and other components, resulting in the same content as the control. Further studies showed that heat treatment could significantly reduce the chilling injury index of banana fruits stored at 7 ℃ and alleviate the chilling injury symptoms of banana fruits. The changes of above volatile substances in ripening banana fruits induced by heat treatment may be closely related to the process of cold resistance induced by heat treatment. Figures and Tables | References | Related Articles

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Isolation and Identification of the Chemical Compositions of Ethyl Acetate and n-Butyl Alcohol Fractions of Ethanol Extract from Mesembryanthemum crystallinum LI Tingting,DAI Haofu,CAI Caihong,GUO Zhikai,XIA Zhihui,ZENG Yanbo 2020, 41 (6):  1234-1241.  doi: 10.3969/j.issn.1000-2561.2020.06.023 Abstract ( 394 )   HTML ( 9 )   PDF (1477KB) ( 368 )   In this paper, 11 monomer compounds were isolated and identified from the ethyl acetate and n-butyl alcohol fractions of ethanol extract from Mesembryanthemum crystallinum L with a variety of column chromatography and spectroscopic techniques. There were two propyl compounds: cis-p-hydroxycinnamic acid (4), ferulic acid (3), two alkaloid compounds: nicotinic acid (6), ethane-1,2-diyl Dinicotinate(7), five glycosides: 2-ethoxy-5-(hydroxymethyl)-tetrahydrofuran-3,4-diol(5), 3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl(E)-3-(4-hydroxy-3-methoxy-phenyl) acrylate(8), (E)-2-(hydroxymethyl)-6-(4-(3-hydroxyprop-1-en-1-yl)-2-methoxyphenoxy) tetrahydro-2H-pyran-3,4,5-triol(9), 6-((1R,2S)-2-hydroxy-4-((S,E)-3-hydroxybut-1-en-1-yl)-3,5,5-trimethylcyclohex-3-en-1-yl)oxy)-5-(hydroxymethyl) tetrahydro-2H-pyran-2,3,4-triol(10),(E)-4-hydroxy-3,5,5-trimethyl-4-(3-((3,4,5-trihydroxy-6-(hydroxymethyl)t) etrahydro-2H-pyran-2-yl)oxy) but-1-en-1-yl) cyclohex-2-en-1-one(11),one phenylpropanone: ryeganolide (2),one steroidal compound: β-sitosterol (1). The study would enrich the research on the chemical constituents in M. crystallinum L. and provide a theoretical basis for the better development of the functional components of M. crystallinum L. Figures and Tables | References | Related Articles

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Ultrasound-microwave Assisted Extraction and Antioxidant Activity of Total Flavonoids from Hibiscus sabdariffa L. HUANG Qiong,HUANG Xiaomei 2020, 41 (6):  1242-1250.  doi: 10.3969/j.issn.1000-2561.2020.06.024 Abstract ( 320 )   HTML ( 5 )   PDF (6617KB) ( 267 )   The ultrasonic-microwave assisted extraction of the flavonoids from Hibiscus sabdariffa L. was optimized by response surface analysis with a Box-Behnken design. The effects of five important factors, liquid-material ratio, ethanol concentraion, extraction time, microwave power and the extraction times, on the flavonoids extraction of H. sabdariffa Lwere investigated in the single factor experiments. The regression model of the liquid-material ratio, ethanol concentration and microwave power to solvent was established. The optimum technology condition for the ultrasonic-microwave assisted extraction of the flavonoids from H. sabdariffa L. was determined as follow: the ethanol concentration 40%, liquid-material ratio 50∶1 (mL/g), microwave power 250 W, extraction time 20 min and ultrasonic power 50 W, extracted twice. Under the conditions, the flavonoids yield was 40.2 mg/g. Using vitamin C as the control, the antioxidant activity of the crude extract and purified flavonoids was studied. The crude extract and purified flavonoids from H. sabdariffa L. had a strong antioxidant activity, and they had an antioxidation effect on DPPH and O -2?, and the scavenging activity had an obvious dose-effect relationship of concentration, but the antioxidant activity was weaker than that of vitamin C. Figures and Tables | References | Related Articles

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Change of Aroma Components in Different Storage Conditions of Kiwifruit CHEN Yiting,LAI Ruilian,FENG Xin,CHENG Chunzhen,ZHONG Chunshui,GAO Minxia,WU Rujian 2020, 41 (6):  1251-1256.  doi: 10.3969/j.issn.1000-2561.2020.06.025 Abstract ( 382 )   HTML ( 9 )   PDF (1361KB) ( 261 )   The fruits of Actinidia deliciosa cv. Miliang-1 were used as the materials to identify the aroma components of kiwifruit, and the changes in different storage conditions that treated at 25 ℃, 4 ℃ and ABA were studied using a gas chromatography-mass spectrometry. There were 38 aroma components in kiwifruit, with aldehyde and alcohol as the main aroma components. Hexenal, aldehyde and 1-hexanol accounted for 39.25%-61.15%, 12.63%-18.15% and 4.22%-11.60% of the aroma components. Compared with the CK group, the relative content of hydrocarbons, esters and alcohols increased, while the relative content of aldehydes decreased after stored at 25 ℃. The relative content of hydrocarbons and esters increased, and aldehydes and alcohols decreased after treated at 4 ℃. When treated by ABA, the relative content of hydrocarbons, aldehydes and esters increased, while the relative content of alcohols decreased. The results reflected in this study would provide a scientific basis for the storage and softening mechanism research of kiwifruit. Figures and Tables | References | Related Articles

Ecology

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Yield Change and Carbon Emission Reduction & Fixation Potential of Banana in Mountain Areas in Mode of Chemical Fertilize Reduction ZHOU Jinsong,WANG Chao,ZHI Jiazeng,DU Hao,LI Zongkai,GAO Mei,SUN Yinhu,ZHANG Guangyong,CHEN Weiqiang 2020, 41 (6):  1257-1264.  doi: 10.3969/j.issn.1000-2561.2020.06.026 Abstract ( 329 )   HTML ( 7 )   PDF (1403KB) ( 267 )   In the study, a field test method was conducted to measure and estimate the economic yield, economic coefficient, carbon emissions and carbon fixation of mountain bananas in the chemical fertilizer reduction model. There was no significant change in the economic yield of banana with 20% reduction of chemical fertilizer comparing with the conventional fertilization. Banana yield decreased by 24.1% when the reduction of chemical fertilizer reached 30%. When chemical fertilizer was reduced by 10%, 20%, 30% respectively, the carbon fixation of banana plants decreased by 2.15%, 3.51% and 11.33%, and the carbon emissions from chemical fertilizers decreased by 10.01%, 10% and 10% except the soil carbon emissions of the treatment of 10% chemical fertilizer reduced increased by 12.67%, that of the others decreased by 16.94% and 3.41%. Based on the plant carbon fixation and soil carbon emission, the estimation by net carbon emission of per banana plant, the net carbon emission of each banana plant of the treatment of the conventional fertilization, chemical fertilization reduced by 10%, 20%, 30% was 4731.29, 5529.03, 4418.47 and 4415.30 g/plant, respectively. To guarantee the production, chemical fertilization reduced by 20% had the greatest potential of carbon fixation and emission reduction. The study showed that reasonable reduction of chemical fertilizer could achieve a win-win situation of the economic and ecological benefits of banana planting in mountainous areas. Figures and Tables | References | Related Articles

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Iron Plaque Formation on Roots from Different Oryza rufipogon Populations TANG Lu,WANG Sheng,DAN Jianguo 2020, 41 (6):  1265-1272.  doi: 10.3969/j.issn.1000-2561.2020.06.027 Abstract ( 455 )   HTML ( 4 )   PDF (1575KB) ( 246 )   In order to determine the effects of root characteristics on iron plaque formation on the roots of O. rufipogon, eight populations were collected from different areas in Hainan, and investigated with hydroponic experiments. Iron plaque was induced by exposing the roots to a Kimura B nutrient solution supplemented with 0.532 mmol/L FeSO4 for 24 h. All the four iron plaque indices showed that iron plaque formation on the roots was significantly different among the O. rufipogon populations. The relative amount of iron plaque for HLY, XLB, and HQF populations was 480.58, 382.66, 364.05 mg Fe/(cm·plant), respectively, which was much higher than those for the others. The amount of iron plaque per plant was positively related to most parameters of the roots, such as root biomass, surface area of adventitious roots, surface area of lateral roots, surface area and volume of root system. The relative amount of iron plaque on the roots had positive correlation with surface area of the lateral roots and its proportion, as well as root biomass and volume of root system. The content of iron plaque on the roots was only positively related to the proportion of surface area of the lateral roots. However, the amount of iron plaque per root surface area was not significantly correlated with the above parameters of the roots. All the four iron plaque indices had no correlation with root porosity. In summary, the major factors influencing iron plaque formation on the roots were surface area of lateral roots and its proportion, which could be used as the pivotal root parameters for confirming the populations of O. rufipogon with more iron plaque on roots. Figures and Tables | References | Related Articles

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Changes of Vegetation and Soil Nutrient in Different Forests after Logging Banin Tropical Coastal Area of Hainan Island XUE Yang,LIANG Juzhi,SU Shaofeng,YAO Xiaolan,WANG Xiaoyan,LIN Zhipan,XUE Yanwen 2020, 41 (6):  1273-1278.  doi: 10.3969/j.issn.1000-2561.2020.06.028 Abstract ( 273 )   HTML ( 5 )   PDF (1371KB) ( 241 )   The changes of vegetation structures and soil nutrients in coastal forests are important to understand the forest ecological process and restoration of saline-alkali land, and for the biodiversity conservation and ecosystem service function enhancement. The vegetation and soil nutrient characteristics of three types of plantations (Acacia auriculiformis, Casuarina equisetifolia and Eucalyptus robusta), secondary forests and mixed forests (control) banned from cutting in low altitude coastal areas of northern Hainan Island in 1994 were studied using the typical plot method. 57 species belonging to 54 genera and 34 families were investigated. The species composition of the secondary forest and mixed forest communities was richer than that of the pure forest, and no shrubs grew in the C. equisetifolia plantation. In addition to the secondary forests, other forest types had the most abundant species in herblayer. The soil of the five forest plots was acidic, and the content of organic matter and total N in the Eucalyptus robusta plantation, secondary forest and mixed forest was the highest, but the content of available P in the A. auriculiformis and C. equisetifolia plantation was significantly higher than that of the others (P<0.05). Except the mixed forest, available K was 11.27 mg/kg, and that in the other forest types was very low or even undetected. There existed positive correlation between organic matter in the secondary forest, available K in the mixed forests and species compositions. There existed positive correlation in total nitrogen, tree age and height. Therefore, soil nutrients increased with the increase of cutting time. The E. robusta forest had higher organic matter and nitrogen content, but the C. equisetifolia and A. auriculiformis forests had higher phosphorus content, while the secondary mixed forest had higher potassium content. Figures and Tables | References | Related Articles