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2023, 36(4)
2023, 36(4): 1-2.
Response of Different Rootstocks and Resistant Resin Components of Pinus massoniana to Pine Wood Nematode
LI Wen-hua, LIU Qing-hua, ZHOU Zhi-chun, GAO Kai, Luo Ding-hui
2023, 36(4): 1-11. doi: 10.12403/j.1001-1498.20220419
Objective By inoculating Pinus massoniana Lamb. with pine wood nematode, the changes of pine resin components before and after inoculation were analyzed, so as to provide a theoretical basis for the study of resistance of P. massoniana to pine wood nematode disease. Method The experimental material were 5-year-old clones of P. massoniana in Linhai City, Zhejiang Province. We extracted the pine resin components of P. massoniana rootstocks and P. elliottii rootstocks, highly resistant and susceptible P. massoniana inoculated with pine wood nematode for 1, 7 and 15 days and also analyzed the content and dynamic changes of each pine resin component. The effective terpenes were used to treat pine wood nematode. Then we analyzed the survival rate of pine wood nematodes. Result The results showed that 19 oleoresin terpenoids were Identified. The abundant terpenoids were α-pinene, β-pinene, carylene, pimaric acid, sandaracopimaric acid, palustric acid/levopimaric acid, dehydroabietic acid, neoabietic acid and abietic acid. In the rootstock of P. massoniana, the content of β-myrcene was significantly higher than that of P. elliottii rootstock 1day after inoculating with pine wood nematode(p<0.05); the contents of the above components had no significant difference among different rootstocks after inoculating with pine wood nematode 7 days and 15 days. The contents of α-pinene, β-pinene, β-laurene, limonene, borneol, longifolene, α-caryophyllene, trans-β-farnesene and neoabietic acid in different resistant P. massoniana changed differently after inoculation with pine wood nematode. In the high resistance P. massoniana, the contents of α-pinene and β-pinene were significantly higher than those of susceptible P. massoniana 1 day after inoculating with pine wood nematode(p<0.05); In the high resistance P. massoniana, the content of α-pinene, β-pinene, limonene and longifolene were significantly higher than those of susceptible P. massoniana 7 days after inoculating with pine wood nematode(p<0.05); The situation was the same when pine wood nematode was inoculated for 15 days as when pine wood nematode was inoculated for 7 days. The result of gradient concentration test of the above terpenoids showed that: when the concentration of α-pinene was 150 mg·g−1 for 0.5 h, the survival rate of pine wood nematode was 20%. Different concentrations of β-pinene solution had the same inhibitory effect on pine wood nematode, and the survival rate reached about 50% when treated for 0.5h. When limonene solution concentration was 10mg·g−1 for 0.5 h, the survival rate of inhibited pine wood nematode was almost zero. When the concentration of longifolene was 10mg·g−1 for 0.5 h, the survival rate of pine wood nematode was 18%. Conclusion There are no obvious relationships between different rootstocks and resistance to P. massoniana. There are significant differences in α-pinene, β-pinene, limonene and longifolene contents between high and susceptible P. massoniana inoculated with pine wood nematode, and the content of high resistance P. massoniana was significantly higher than those of susceptible P. massoniana. At low concentrations α-pinene, β-pinene, limonene and longifolene inhibit the activity of pine wood nematodes, which shows the four terpenoids are related to resistance of P. massoniana.
Efficient Transformation System of Agrobacterium tumefaciens Mediated Transformation of Purpureocillium lilacinum by Using beta-tubulin as Selectable Marker
WANG Xi-zhuo, WANG Lai-fa, CAO Ye-fan, HU Jian, WANG Xiang, QIN Yan, WANG Yong-chun
2023, 36(4): 12-19. doi: 10.12403/j.1001-1498.20230056
Purpose To establish an efficient transformation system of the nematopathogenic fungus Purpureocillium lilacinum and obtain its insertional mutagenesis. Methods The benomyl resistance gene beta-tubulin being as the selective marker, Agrobacterium tumefaciens-mediated transformation technique was developed to screen different pathogenicity mutants in P. lilacinum. PCR amplification and Southern hybridization were used to verify the transformation events, and Southern blotting of beta-tubulin gene and cloning of transforming DNA (T-DNA) flanking sequences were used to determine insert number and site of T-DNA in the fungal genome, respectively. Results A reliable transformation method was established for P. lilacinum. Specifically, pre-germinating spores of P. lilacinum used at co-cultivated period was a prerequisite.P. lilacinum germinating spores co-cultivated with A. tumefaciens EHA105 at 25 ℃ for 48 h achieved the highest transformation efficiency, which was 1 200-3 200 transformants per 106 spores, and the ratio of positive resistant transformants was 96%. The transformants were cultivated up to 5 generations on beta-tubulin-containing medium and confirmed by PCR and those genetic traits remained stable. Southern hybridization showed that 83.3% of the transformants were single copy insertions of T-DNA, and 16 mutants with virulence variants were screened from 20 transformants. Conclusion This study successfully constructed an efficient genetic transformation system mediated by A. tumefaciens with beta-tubulin gene as a selective marker, and obtained an insertion mutant with pathogenicity variation, which was P. lilacinum. It provides insights into studying gene function, pathogenic mechanism and breeding excellent strains.
Spatial Heterogeneity and Reasonable Sampling Sizes of Rainfall In a Larix gmelinii var. principis-rupprechtii (Mayr) Pilg. Plantation in the Semi-humid Liupan Mountains
CHAO Yang, YU Song-ping, LIU Ze-bin, MA Xin, GUO Jian-bin, WANG Yan-hui
2023, 36(4): 20-30. doi: 10.12403/j.1001-1498.20220402
Objective Spatial heterogeneity of rainfall in the forest has an important impact on soil moisture and growth of understory vegetation. Therefore, accurately describing the spatial variability of rainfall in the forest under the forest canopy and determining the reasonable sampling sizes are helpful to accurately understand the impact of forest on hydrology. Method A Larix gmelinii var. principis-rupprechtii (Mayr) Pilg. plantation in the Xiangshuihe small watershed of the semi-humid Liupan Mountain was set up to collect the rainfall in the forest for each rainfall event based on 40 deployed collectors during the growing season (June-Oct.) of 2021. The spatial variabilities of rainfall in the forest during the leaf-expanding and leaf-withering periods were analyzed, and the reasonable sampling sizes of collectors were quantified. Result (1) During the growing season, the total rainfall depth inside the forest was 440.0 mm, accounting for 77.5% of the corresponding gross rainfall, and the coefficient of variation of rainfall in the forest was 28.23%. The total rainfall in the forest was 153.8 and 290.2 mm during the leaf-expanding and leaf-withering periods, accounting for 73.0% and 80.2% of the corresponding gross rainfall, and the coefficient of variation of rainfall in the forest was 36.0% and 18.5%, respectively. In general, the spatial variability of rainfall in the forest first decreased rapidly and then gradually stabilized with the increase of rainfall, rainfall intensity and rainfall duration. (2) The nugget/still (range) of rainfall in the forest was 0.042 (4.8 m) in the growing season, 0.012 (4.0 m) in leaf-expanding period and 0.275 (6.5 m) in leaf-withering period, respectively. (3) Within the 95% confidence interval, if the error is controlled within 5%, at least 17 and 14 collectors with a sectional area of 235.58 cm2 should be installed in the leaf-expanding and leaf-withering periods, respectively. Conclusion Affected by differences in rainfall and canopy structure, the spatial variability of rainfall in the forest varies between leaf-expanding and leaf-withering periods. The reasonable sampling sizes of collectors in leaf-expanding and leaf-withering periods are closely related to the spatial variability of rainfall in the forest. The impact of the difference in reasonable sampling sizes of collectors in different periods should be paid attention to ensure the accuracy in rainfall in the forest assessment during the whole growing season.
Variation and Selection of Growth and Form-quality Traits of 3-year-old Cyclobalanopsis gilva
YANG Meng-qing, SHAO Wei-zhong, XU Yong-hong, YAO Jia-bao, OUYANG Tian-lin, DAI Li-hua, ZHOU Zhi-chun, WANG Bin
2023, 36(4): 31-40. doi: 10.12403/j.1001-1498.20220563
Objective To reveal the genetic variation rule of the growth and form-quality traits of the 3-year-old elite families of Cyclobalanopsis gilva in different locations, and select the fast-growing and high-quality families with genetic stability for different regions and sites. Methods Based on the genetic assay forest constructed in Jiande of Zhejiang Province, Fenyi and Anyuan of Jiangxi Province with 1-year-old container seedlings of 42 elite families plantations of C. gilva in 2019, a whole forest survey was conducted and the differences of traits, heritability and genetic correlation, as well as the interactions between families and locations were analyzed using SAS software, and a batch of fast-growing and high-quality families were selected based on principal component analysis and BLUP methods. Results The average tree height and ground diameter of 3-year-old C. gilva were 2.04 m and 3.15 cm, respectively. The estimated family heritability of tree height, ground diameter, crown width and longest branch length were high (0.393-0.753). Compared with family heritability, individual heritability estimates was relatively low. The correlation between traits of different families was high, and the families with excellent tree height and ground diameter performance had straighter form, fewer branching trunks but more branches, longer and thicker branches than the families with low tree height and small ground diameter. The interaction effect of family × site was obvious, and the site had a great influence on the growth. The best growth performance was found in Jiande site, followed by Anyuan and Fen Yi. Based on the comprehensive ranking of growth and form-quality traits, HNCB8 and HNHT5 ranked first in the three test sites, showing a good overall performance. The top 20% BLUP values of tree height and ground diameter were selected, and a total of 10 excellent families were selected from the three test sites. HNCB8 was selected as a common family. Conclusion There are rich genetic differences in growth and form-quality traits among the 3-year-old C. gilva, and the family heritability is generally high, which is subject to strong genetic control. The change of planting habitat has a great influence on the family of C. gilva, and the comprehensive performance of HNCB8 and HNHT5 is better, which has the potential for promotion.
Establishment of Tissue Culture System of the Ancient Trees of Platycladus orientalis
CHANG Er-mei, JIANG Ze-ping, LIU Jian-feng, JIA Zi-rui, LI Xiang, ZHANG Jian-qiang, ZHAO Xiu-lian
2023, 36(4): 41-49. doi: 10.12403/j.1001-1498.20220498
Objective This study aims to establish a tissue culture system for ancient Platycladus orientalis for overcoming the difficulties such as non-thoroughness of disinfection and sterilization, sever browning, and weak meristematic ability. Method In this study, the new shoots of about 3 000-year-old P. orientalis were used as explants, and aseptic explants were obtained through disinfection and sterilization. The tissue culture system for ancient P. orientalis was established by selecting the appropriate culture medium and hormone. Result Disinfecting the explants from ancient P. orientalis using 0.3% HgCl2 for 10 min showed the best sterilization effect, with a pollution rate of 25.81% and the survival rate of 54.82%. The effect of using 3% sucrose as the sugar source for the tissue culture medium of ancient P. orientalis was better than that of 3% glucose. The results of antioxidant and adsorbent tests demonstrated that the browning rate of explants was the lowest under the addition of 3.00 g·L−1 active carbon to the explant initiation medium. The optimal primary culture medium for tissue culture of ancient P. orientalis was 1/2MS + NAA 0.2 mg·L−1 + 6-BA 0.1 mg·L−1, with the induction rate of adventitious buds of 32.05%, rapid bud growth, as well as tender green and robust buds. The optimal proliferation medium was 1/2MS + 6-BA 0.05 mg·L−1 + NAA 0.2 mg·L−1 + KT 0.1 mg·L−1, with the proliferation coefficient reaching 1.93, and rapid growth of green and robust buds. The optimal rooting culture medium was WPM + NAA 0.5 mg·L−1 + IBA 0.5 mg·L−1, which achieved a rooting rate of 9.12%, with an average number of roots per plant of 2.67, and an average root length of 1.23 cm. A total of 24 rooting seedlings were obtained. Two months later, red roots appeared in 2 plants, and the tender buds continued to grow. The tissue-cultured rooting seedlings of ancient P. orientalis were successfully obtained. Conclusion The selection of culture medium and the ratio of auxin to cytokinin are important factors for the proliferation and adventitious root formation of ancient P. orientalis. This study provides a reference for tissue culture of other Cupressaceae trees.
Radial Growth in Response to Hydrothermal Environment of Larix principis-rupprechtii in Hanshan, Inner Mongolia
CHEN Jia-jia, ZHOU Mei, ZHAO Peng-wu, XU Chong-yang, SHI Liang, BAO hu, LIU Yan-jun, CAO Guang-ming
2023, 36(4): 50-58. doi: 10.12403/j.1001-1498.20220467
Objective :In the semi-arid regions of northern China, due to the long-time seasonal drought deficit, trees growth is sensitive to climate change. With rapid warming and associated increasing evapotranspiration in recent decades, the growth of trees in the semi-arid regions is gradually restricted by climate drying. Therefore, it is important to understand the pattern of trees growth and its response to environment for better management. This study aims to systematically analyze the radial growth of larch (Larix principis-rupprechtii) in semi-arid regions of China and its relationship with environment factors (temperature, precipitation and so on), to provide a theoretical support for understanding response of trees growth to environment change in semi-arid regions of northern China. Methods :The radial growth of four sample trees of Larix principis-rupprechtii was continuously measured with high resolution using point dendrometer systems in the Hansan National Nature Reserve, Zalut Banner, Tongliao City. Environment factors including temperature, rainfall, soil water content and so on were measured for analyzing the relationship between radial growth and environmental factors. Results :The radial growth of larch contracted during the day and expanded at night. From May to June, the contraction and expansion of larch stems were much higher than those from July to September; Radial growth of larch (Larix principis-rupprechtii) was significantly influenced by soil temperature throughout the growing season scale, but soil moisture content was an important factor affecting radial growth at different growing stages. In the year 2021 with extreme rainfall, radial growth of larch before the rainfall peak accounted for 45% of the total annual growth, indicating that soil temperature and water content are important factors affecting radial growth of larch. Precipitation in summer contributed less to trees growth, while soil moisture supply after winter snow-cover melting in spring was a key factor in determining radio growth. Conclusions : In the semi-arid region of Inner Mongolia, our results suggested that precipitation has little contribution to radial growth of larch, but indirectly affects radial growth through soil moisture. Soil temperature and soil moisture are important factors affecting radial growth. At the beginning of the growing season, when soil moisture is not effectively supplemented by rainfall, radial growth mainly depends on the limited water reserved in the soil.
Effect of Exogenous Application Glutamate on Drought Tolerance of Populus alba × P. glandulosa ‘84K’
LIU Yu, QU Mei-qiao, ZHENG Rui-jie, YU Jin-jian, GENG Ya, AN Yi, HAN Xiao, HUANG Li-chao, ZENG Wei
2023, 36(4): 59-71. doi: 10.12403/j.1001-1498.20220572
Objective Glutamate is a ubiquitous amino acid in plants, which plays an important role in amino acid metabolism. In this study, poplar 84K (Populus alba × P. glandulosa '84K') was used to analyze the effect of glutamate on the growth of 84K poplar under drought stress, and to explore the role of glutamate in the drought tolerance of 84K poplar. This study provides insights into the amino acid metabolism relating to forest stress resistance. Method 84K grown for 2 months were subjected to drought after glutamate treatment and re-water to analyze phenotypic and physiological changes, including the leaf water content, electrolyte permeability, glutamic acid content, osmotic adjustment substance content, active oxygen content, active oxygen scavenging enzyme (CAT, POD, and SOD) activity and so on. Result The drought test after glutamate treatment showed that glutamate could improve the drought tolerance of plants. Compared with normal drought plants, the relative water content of the leaves increased by 30.3%, the proline content increased by 33.1%, the electrolyte permeability decreased by 54.0%, and the expression of proline synthesis-related genes P5CS, P5CR, and P5CDH significantly increased, 2.47 times, 2.57 times and 8.89 times higher than that of the control, respectively. The expression of proline degradation gene PDH decreased by 48.8%. In addition, glutamate treatment plants could maintain higher CAT, POD, and SOD enzyme activity levels, which were 1.67 times, 1.35 times, and 1.17 times higher than those of normal drought plants, respectively, and the hydrogen peroxide content decreased by 19.3%. The application of glutamic acid after drought significantly enhanced the recovery ability of drought plants. Compared with the re-water plants, the relative water content of the plant leaves increased by 1.08 times, the proline content increased by 1.09 times, the electrolyte permeability decreased by 12.1%, the CAT activity and POD activity increased by 19.0% and 62.9%, respectively, and the hydrogen peroxide content also decreased by 31.2%. Conclusion Exogenous application of glutamic acid can increase the endogenous glutamate content of 84K poplar, induce proline synthesis and accumulation, reduce the electrolyte permeability and oxidative damage caused by drought stress, and effectively alleviate the water stress of plant leaves, thus reducing the sensitivity of plants to drought. Therefore, the exogenous application of glutamic acid can strengthen amino acid metabolism, improve antioxidant capacity and osmotic adjustment ability, and improve the adaptability of 84K poplar in a drought environment, which plays a reference value in revealing the role of glutamic acid in abiotic stress.
Characteristics of Soil Organic Carbon Pools and Their Influencing Factors under Different Stand Types in the Plain Sandy Area
WANG Lei, LIU Qing-yi, GUAN Qing-wei, SHI Jing-pan, PENG Ting-ting, ZHU Xiang-cheng, YANG Yue, LIU Jing
2023, 36(4): 72-81. doi: 10.12403/j.1001-1498.20220553
Objective By investigating the characteristics of soil organic carbon pools under different stand types, this study aims to provide a theoretical basis for the enhancement of soil carbon pools and ecological restoration in plain sandy areas. Method Soil organic carbon (SOC), labile organic carbon fractions and soil enzyme activities were measured in five soil layers (0-20, 20-40, 40-60, 60-80 and 80-100 cm depth) for three 16-year-old stand types (poplar pure plantation, willow pure plantation and poplar-willow mixed plantation) and a nearby abandoned land (as control) at a typical plain sandy area of Feng County, Jiangsu Province. The carbon pool management index (CPMI) was estimated for the examined stands. The correlations between soil carbon pool characteristics and environmental factors therein were also analyzed. Result (1) In general, the organic carbon content (SOC) and storage (SOCS) of the three forest types and the control soil layers ranged from 1.03 to 5.88 g·kg−1 and 3.53 to 17.55 t·hm−2, respectively. Among them, the SOC content increased by 45.2%-82.2% in the forested sites compared with the control site, and the SOCS in the 0-100 cm soil layer of pure poplar forest was 1.23, 1.24, and 1.83 times that of pure willow forest, mixed willow forest and the control, respectively. (2) Compared with the control, the soil labile organic carbon fractions, including easily oxidizable organic carbon, dissolved organic carbon and microbial biomass carbon, increased by 28.6%-48.0%, 6.8%-9.7% and 21.6%-33.4%, respectively. The CPMI was significantly higher than 100% for the three stand types (P<0.05). (3) Soil invertase activity and polyphenol oxidase activity were significantly affected by stand types, and the polyphenol oxidase activity of poplar-willow mixed plantation was significantly higher than that of poplar pure plantation and control (P<0.05) in 0-100 cm soil layer. (4) Pearson correlation analysis showed that characteristics of SOC pools were significantly affected by polyphenol oxidase and β-glucosidase activities(P<0.05), SOC, SOCS, EOC and CPMI were significantly affected by invertase, peroxidase activities. MBC was significantly affected by invertase activity. Redundancy analysis showed that soil carbon to nitrogen ratio and fine root biomass were the main factors in affecting the characteristics of SOC pools in the study area. Conclusion Plantation in plain sandy soil area can improve soil organic carbon, active components and stability of organic carbon pool, and pure poplar forest has the best effect on improving soil organic carbon storage.
Metabonomic Analysis of Targeted Flavonoids for Tepals of Different Flower Color Types of Wintersweet
SHEN Zhi-guo, CHENG Jian-ming, WU Fang-fang, DING Xin
2023, 36(4): 82-89. doi: 10.12403/j.1001-1498.20220537
Objective Targeted flavonoid metabolome detection and analysis were carried out to provide reference for further analysis of color substances and flavonoid metabolism pathway in the tepals of different flower color types of wintersweet using the middle and inner tepals of three cultivars of Rubrum wintersweet, Patens wintersweet, and Concolor wintersweet at early flowering stage. Methods UPLC-MS/MS was used to detect the middle and inner tepals of three wintersweet cultivars, and the qualitative and quantitative analysis of metabolites, sample quality control analysis, PCA, HCA, OPLS-DA, KEGG functional annotation and enrichment analysis of differential metabolites were used to explore the differences of flavonoid metabolites in the tepals of different flower color types. Results A total of 82 metabolites were detected in wintersweet tepals, including chalcone, dihydroflavone, flavone, isoflavone, dihydroflavonol, xanthone alcohol, anthocyanin, flavanol; In addition to anthocyanins, the flavonoids in the red tepal of wintersweet also included flavonol compounds, which did not show regular changes in the red and yellow tepals; In the five comparison groups of wintersweet red tepals and yellow tepals, the enrichment of anthocyanin metabolic pathway was the largest and most significant. Conclusion Besides the main flavonol branch and anthocyanin branch, the flavone branch, isoflavone branch, and procyanidin branch may also be included in the flavonoid biosynthesis pathway of wintersweet tepals; The anthocyanin branch and flavonol branch may not compete for the common substrate in the flavonoid biosynthesis pathway of the red tepals of wintersweet; Cyanidin glycosides are the characteristic metabolites of the red tepals in wintersweet, including cyanidin 3-O-glucoside, cyanidin 3-O-rutinoside, and cyanidin 3-O-galactoside.
Effect of Shading on Appearance and Nutrient Content in Different Parts of Pseudosasa amabilis Shoots
GUO Yang, YU Xue-jun
2023, 36(4): 90-98. doi: 10.12403/j.1001-1498.20220611
Objective The effects of different light intensities on appearance and nutritional components in different parts of Pseudosasa amabilis shoots were studied to provide guidance for the quality control and scientific cultivation of bamboo shoots. Method Bamboo shoots were shaded by bagging. After harvesting, the changes of appearance indexes and nutrient contents in different parts of bamboo shoots were measured and analyzed. Result After shading, the base diameter, length, individual weight of Pseudosasa amabilis shoots, and chlorophyll content decreased, by contrast, L* value, a* value, b* value, and anthocyanin content increased. There was a significant correlation between pigment content and color index. With the decrease of light intensity, the content of protein and fat in the tip of bamboo shoots increased, and total amino acids and the proportion of essential amino acids in the middle of bamboo shoots increased first and then decreased. The proportion of sweet, bitter and aromatic amino acids in the base of bamboo shoots decreased first and then increased. The ash content of each part increased first and then decreased, the content of soluble sugar decreased first and then increased, and the content of vitamin C, cellulose and phenols decreased. Conclusion After shading, the appearance quality of Pseudosasa amabilis shoots is better than that of no-shading, the content of bitter compounds reduce, and the taste is significantly improved. There are differences in the nutritional components of each part under different light intensities.
Phenotypic Difference Analysis and Screening Stability Indexes of Different Chinese Chestnut Varieties Nuts
LI Tong-tong, GUO Su-juan, JIANG Xi-bing
2023, 36(4): 99-108. doi: 10.12403/j.1001-1498.20220614
Objective By comparing and analyzing the phenotypic traits of different varieties of chestnut, we screened out the indicators with large phenotypic differences and not easily affected by the environment for providing reference for the identification and accurate application of chestnut varieties in production practice. Method The differences and diversity of 21 phenotypic characters of 3 200 nuts from 80 varieties in different Chinese chestnut producing areas were analyzed. The correlation between phenotype and environmental factors was analyzed, and the stability index with a small coefficient of variation was screened out. The stability of three varieties cultivated in multiple fields was verified. Result (1) There were significant differences in the phenotypic indexes of chestnut in different regions and the nut size and hilum size of varieties in Hubei, Jiangsu and Anhui were significantly higher than those in other regions. (2) The variation of 21 phenotypic indexes ranged from 4.05% to 42.28%, and 9 relatively stable indicators with small variation coefficient were screened out, namely nut index, nut roundness, hilum roundness and correlation ratio index, excluding indicators of significant differences within and between groups. (3) Correlation analysis showed that the correlation indexes of nut size and hilum size were positively correlated with mean annual temperature, mean temperature in growing season, annual precipitation and precipitation in growing season, and negatively correlated with annual sunshine duration and growing season sunshine duration. (4) The variation coefficients of 9 phenotypic indexes of nuts from 3 cultivars from different regions ranged from 1.13% to 5.99%. The results of variance analysis showed that the other 8 indexes had no significant differences between regions and individuals except the hilum roundness. Conclusion Different chestnut varieties have rich diversity and significant differences in 21 nut phenotypic indexes, among which 8 nut phenotypic indexes, including nut index, nut roundness, hilum length-to-width ratio, relative hilum size, hilum arc length / nut perimeter, hilum area / transverse area, hilum length/transverse diameter and hilum width / thickness, are stability indexes. It can be applied to the identification of chestnut varieties in production practice.
Chloroplast Genome Phylogeny and Codon Preference of Anabasis aphylla L.
JIANG Ping, HUANG Xiang, SULAIMAN Shah, HE Meng-yao
2023, 36(4): 109-121. doi: 10.12403/j.1001-1498.20220578
Objective To analyze the structural characteristics of Anabasis aphylla chloroplast genome, clarify the taxonomic status of Anabasis in Chenopodiaceae for further exploring its codon preference and determining the optimal codon. Method Total genomic DNA was extracted from fresh assimilation twigs of A. aphylla based on CTAB method. Sequencing was performed using the Illumina Genome Analyzer HiSeq 2000 high-throughput sequencing platform. The chloroplast genome sequence was assembled and annotated by GetOrganelle and Plann. Simple sequence repeat (SSR) in chloroplast genome was analyzed by MISA. Multiple sequence alignment and ML phylogenetic tree construction were analyzed using MAFFT v.7.450 and IQ-TREE v.2.1.1 software. The nucleotide polymorphism values were calculated using DnaSP 6.0 software. The codon preference was studied by CUSP and Codon W 1.4.2. software. Result The full-length chloroplast genome of A. aphylla was 154 084 bp, including a large single copy region (LSC, 85 124 bp), a small single copy region (SSC, 18 934 bp), and a pair of inverted repeat regions (IRa and IRb, 25 013 bp). A total of 132 genes were annotated, including 83 protein-coding genes, 8 rRNA genes, 37 tRNA genes and 4 pseudogenes. The number of SSRs located in the intergenic region was the largest (70.4%), and the number of single-base (A/T) repeat type SSRs was the largest. The optimal model of phylogenetic tree was TVM + F + R3, and Chenopodiaceae was divided into four clustering groups. Among them, A. aphylla showed the closest relationship with Haloxylon and Salsola. TrnS-trnG(exon1)、ndhF-rpl32rpl32-trnLrps16(exon1)-trnQ and ycf1 were high nucleotide polymorphism regions. A total of 20 optimal codons (UUU, UAU, UGU, CAU, UCU, UCA, UUA, CUU, CCU, AGA, GAA, ACU, ACA, AAU, GAU, AAA, GUU, GCU, GGU, CAA) were determined, all ending with A/U. The codon usage preference was mainly affected by natural selection, and the influence of mutation and other influencing factors was weak. Conclusion The chloroplast genome structure of A. aphylla is conservative, showing typical quadripartite structure. In the phylogeny of Chenopodiaceae, A. aphylla has the closest relationship with Haloxylon and Salsola. The identified hypervariable regions and SSR loci can be used for molecular identification of intergeneric species in Chenopodiaceae. The codon of the chloroplast genome of A.aphylla prefer endings with A/U, and the 20 optimal codons determined are useful for the optimization of its exogenous codons. The results can provide a reference for molecular marker development, phylogeny and chloroplast gene engineering of A. aphylla.
Preference of Anoplophora glabripennis to Populus alba var. pyramidalis and Elaeagnus angustifolia
SHAO Peng-peng, YANG Bing-jun, SU Zhi, SUN Zuo-xiang, WANG Zhuo, LIU Yu-ting, WEI Jian-rong
2023, 36(4): 122-128. doi: 10.12403/j.1001-1498.20220595
Objective Populus alba var. pyramidalis is the preferred tree species for the construction of the Protection Forest in northwestern China. However, the long-term single tree species planting has caused the outbreak of the wood borer Anoplophora glabripennis (Asian longhorned beetle, ALB). There was reports that Elaeagnus angustifolia had ‘attract and kill’ effect on ALB, but it was unclear whether it could be used for protecting P. alba var. pyramidalis. Method In this study, we evaluated the possibility of E. angustifolia for protecting P. alba var. pyramidalis by choice experiments of ALB adults’ response to host leaves and trunks of P. alba var. pyramidalis and E. angustifolia both in the laboratory and in the field. The volatiles could stimulate the electrophysiological responses of female antennae were also screened out from both tested host tree species. Result 1) When P. alba var. pyramidalis leaves vs E. angustifolia leaves, ALB females preferred E. angustifolia, and accounted for 80.65% of adults made choice, while males did not show significant preference; 2) cis-3-hexen-1-ol and cis-3-hexenyl acetate from P. alba var. pyramidalis, and cis-3-hexen-1-ol, cis-3-hexenyl acetate, 3-carene from E. angustifolia could arise the antennae responses of female; the ratio of cis-3-hexen-1-ol contents between P. alba var. pyramidalis and E. angustifolia was 2.66:1, and the ratio of cis-3-hexenyl acetate contents between two tree species was 1.19:1; The intensity of electrophysiological activity stimulation varied due to their different content; 3) when tested P. alba var. pyramidalis stem vs E. angustifolia stem in the laboratory, the ALB female preferred gnawing egg niche on E. angustifolia and the number of egg niche could reach to 18 ± 1.73 per stem, but the percent of effective oviposition (eggs laid in the egg niche) on the P. Alba var. pyramidalis (75.00%) in the single choice experiment were higher than that on E. angustifolia (58.33%); 4) The cage experiments on the trunk of the host trees in the forest showed that there was no significant difference in the number of egg niches gnawed by females on the two tree species under no selection conditions, but the larvae did not survive on the E. angustifolia trunk. Conclusion Our results confirmed that the E. angustifolia has a certain degree of attraction to ALB adults, but further researches are requiered to determine whether E. angustifolia can effectively control the ALB population in a certain area.
Selection and Validation of Reference Genes of Broussonetia papyrifera for qRT- PCR under Cadmium Stress
LI Hong-ying, CHEN Meng-di, WANG Zheng-bo, HAO Zi-yuan, LIU Long-chang, ZHAO Xi-ping, NI Jian-wei
2023, 36(4): 129-138. doi: 10.12403/j.1001-1498.20220500
Objective To provide insights into the subsequent research on the molecular mechanism of Broussonetia papyrifera resistance to cadmium(Cd) toxicity, stably expression of reference genes in B. papyrifera under Cd treatment were screened. Method The expression of ten candidate reference genes, including BpUBE2, BpRPL8, BpActin, BpGAPDH, BpHSP, BpTUA, BpDOUB, Bpβ-TUB, BpHIS and BpNADH were detected by real-time PCR (qRT-PCR) technology using root and leaf tissues of B. papyrifera under Cd stress. The geNorm, NormFinder, Bestkeeper and RefFinder reference analysis software were used to analyze the expression stability of ten candidates reference genes. Furthermore, the selected reference genes were verified by the stress response gene BpDREB. Result Gene expression of BpDOUB and BpNADH was relatively stable in different tissues of B. papyrifera under Cd stress, while BpGAPDH expression was the least stable. When the stability of the internal reference was verified with the target gene BpDREB, it was found that the target genes showed similar trends when normalized by the two reference genes BpDOUB and BpNADH, while it is failed to standardize the expression data with BpGAPDH. Conclusion BpDOUB and BpNADH genes as well as the combination of BpDOUB + BpNADH genes can be used as suitable internal reference genes to improve the reliability of gene expression levels analysis under Cd stress in B. papyrifera.
Antibacterial Activities of Rhizospheric Actinomycetes Associated with Casuarina equisetifolia
SHAN Ti-jiang, XIE Yin-yan, YE Da-hang, YANG Yu-ting, LI Wan-lin, MAO Zi-ling
2023, 36(4): 139-148. doi: 10.12403/j.1001-1498.20230002
Objective This study aimed to isolate and identify actinomycetes in rhizospheric soil of Casuarina equisetifolia, determine the antibacterial activity of the rhizospheric actinomycetes, and screen out the actinomycetes isolates with antimicrobial activities. Methods The actinomycetes in the rhizospheric soil of C. equisetifolia were isolated by heat strike dilution method. The actinomycetes isolates were further identified by combining morphological observation with molecular biology method. The antibacterial activities of secondary metabolites produced by the rhizospheric actinomycetes against different bacteria were determined using TLC-bioautography assay. The secondary metabolites in the ethyl acetate layer of rhizospheric actinomycetes were analyzed by HPLC (high performance liquid chromatography). Results A total of twelve actinomycetes strains were isolated and identified from the rhizospheric soil of C. equisetifolia, all of which were the genus of Streptomyces sp., and the maximum similarities were all above 97%. S. spinosus Ceaf-4 and S. chattanoogensis Ceaf-12 had stronger antibacterial activity against Ralstonia solanacearum, and the diameters of antibacterial spots were more than 10 mm. The antibacterial spot diameters of strain S. spinosus Ceaf-4 against Escherichia coli and Staphylococcus haemolyticus were also greater than 10 mm. In addition, S. spinosus Ceaf-4 and S. chattanoogensis Ceaf-12 both contained abundant secondary metabolites, but there were significant difference in the types and relative contents of secondary metabolites. Conclusion There are actinomycetes with Streptomyces sp. as the dominant population in the rhizospheric soil of C. equisetifolia. S. spinosus Ceaf-4 and S. chattanoogensis Ceaf-12 show the stronger inhibitory activity against R. solanacearum and contain abundant secondary metabolites. They can be used as candidate active strains to further explore their antibacterial active components.
Effects of Nitrogen Addition and Closure on Growth and Herbaceous Diversity of Larix principis-rupprechtii Plantation
HUANG Qing-qing, ZHANG Shuai-fa, XU Guo-qiao, LI Xiao, XU Zhong-qi, JIA Yan-long
2023, 36(4): 149-156. doi: 10.12403/j.1001-1498.20220557
Objective The study aimed to reveal the effects of grazing on the diversity of herbaceous plants in Larix principis-rupprechtii plantation and undergrowth under the background of nitrogen deposition. Method Based on the perennial grazing affected Larix principis-rupprechtii plantation in Mulan paddock in Hebei Province, four treatments of control, closure, fertilization, fertilization + closure were set up. The DBH, tree height, crown width growth and herbaceous biomass and diversity of trees in the sample plot were measured, and the effects of 2-year enclosure and fertilization on the growth and herbaceous diversity of Larix principis-rupprechtii plantation were discussed. Result Compared with the control plot, closure, fertilization and fertilization + closure treatments promoted the growth of trees. The tree height increased by about 31.7%, 17.6% and 47.5%, respectively. Among them, there was significant difference between fertilization + closure treatment and control. Closure, fertilization and fertilization + closure all promoted the increase of herbaceous biomass. The local aboveground biomass increased by 5.3, 0.4 and 4.1 times, the underground biomass increased by 4.9, 0.1 and 4.3 times, and the total herbaceous biomass increased by 5.1, 0.2 and 4.2 times, respectively. Herb diversity changed little under closure and fertilization treatments, but species dominance changed significantly under different treatments. Conclusion This study shows that short-term nitrogen addition and closure promote the growth of trees and herbs in Larix principis-rupprechtii forest, have no effects on herbaceous diversity, but significantly change the composition of herbaceous plants.
Evaluation of Resistance to Flower Blight of Camellia Germplasm Resources
LIU Ying, GENG Xian-sheng, YU Wen-xian, LI Ji-yuan
2023, 36(4): 157-164. doi: 10.12403/j.1001-1498.20220382
Objective To develop the evaluation technology for flower blight resistance of Camellia germplasm resources and evaluate the resistance levels of Camellia germplasm resources to flower blight. Method The time gradient of three germplasm resources with different resistance was used to analyze the effects of different culture time on the resistance evaluation after inoculating the hyphae plug of Ciborinia camelliae. We calculated the relative area of lesion and disease index of Camellia germplasm resources after inoculation, formulated the severity grading criteria and resistance evaluation criteria, and established the resistance evaluation technology of Camellia germplasm resources to flower blight. This technique was used to evaluate the resistance of 56 germplasm resources to flower blight. Result Inoculating hyphae plug on the detached petals of Camellia germplasm resources, and calculating the relative area of lesions at 72 hours after inoculation, could accurately evaluate the disease resistance of Camellia germplasm resources. The results of resistance evaluation of 56 germplasm resources showed that 8 germplasm resources were immune or highly resistant to flower blight, 24 germplasm resources were medium resistant, 14 germplasm resources were medium susceptible, and 10 germplasm resources were highly susceptible. Resistance levels among different sections of Camellia germplasm resources were different, and the resistance levels of different species within the same sections and different crosses of the same parent were also different. Conclusion In this study, resistance evaluation technology of Camellia germplasm resources to flower blight has been established. The resistance level of 56 germplasm resources was identified, and 8 germplasm resources with immune or highly resistant to flower blight were screened out.
Effects of Nitrogen and Biochar Addition on Arbuscular Mycorrhizal Fungi Colonization Rate and Spore Density in Moso Bamboo Plantations
SHI Xue-rong, Huang Hong-liang, JI Hang-xiang, ZHAO Ming-shui, ZHANG Hua-feng, LI Quan, SONG Xin-zhang
2023, 36(4): 165-172. doi: 10.12403/j.1001-1498.20220448
Objective To investigate the effects of nitrogen (N) deposition and biochar addition on arbuscular mycorrhizal fungi (AMF) characteristics in Moso bamboo (Phyllostachys edulis (Carrière) J. Houz.) plantations for providing scientific reference for sustainable management of Moso bamboo plantations under global change. Methods We investigated the effects of different N addition rates (0, 30, 60, and 90 kg N·hm−2·yr−1), biochar addition rates (0, 20, and 40 t BC·hm−2), and their combination on the AMF colonization rate, spore density and soil properties of Phyllostachys edulis plantations. Results Compared with the control (0 kg N·hm−2·yr−1 + 0 t BC·hm−2), N addition significantly reduced the colonization rate of AMF (16.1%~51.7%). High biochar addition (40 t BC·hm−2) significantly reduced the colonization rate of AMF (46.0%), but increased the spore density (162.5%). Under the N addition treatments, biochar addition increased the colonization rate of AMF, and had no significant effect on spore density. The colonization rate of AMF was significantly positively correlated with soil pH, and negatively correlated with available N and available phosphorus. The spore density of AMF was significantly positively correlated with available phosphorus. Conclusion Under the N addition treatments, biochar addition increased the colonization rate of AMF and enhanced the symbiotic relationship between Moso bamboo and AMF, indicating that biochar addition is an effective measure to achieve sustainable management of Moso bamboo plantations under the background of N deposition.
Differences in Leaf Functional Traits of Caragana intermedia Planted in Different Years
LI Qin, WANG Lei, ZHANG Xue, PAN Yu-ling, WANG Yue, YU Dian
2023, 36(4): 173-182. doi: 10.12403/j.1001-1498.20230082
Objective To compare the differences in leaf functional traits of Caragana intermedia plantations with different planting years for and provide a scientific basis for studying the adaptation mechanism of C. intermedia in response to environmental changes in the arid area. Method Based on the plantations with four different planting years (16, 25, 34, and 46a), we analyzed the leaf functional traits in C. intermedia. Result There were significant differences in the morphological and functional traits of leaves of C. intermedia planted in different years. The LDMC of C. intermedia with 46 years of age was significantly higher than those have ages of 16, 25, and 34 a (P<0.05), and the SLA was significantly higher than that with ages of 16 and 34 a (P<0.05). LL, LW, LFW, LDW, and LA all increased first and then decreased, which showed a growth trend of 25 a>34 a>16 a>46 a. The coefficient of variation of leaf morphology and function traits of C. intermedia was 7.57%~46.98%, among which the coefficient of variation of LFW, LDW, LA and SLA of 16-year-old C. intermedia was the highest. Among the structural and functional traits of leaves, the VB and USA of C. intermedia with 46-year-old were significantly lower than those in with 34-year-old (P<0.05), and there was no significant difference between 16-year-old and 25-year-old. The stomatal density of the epidermis varied greatly. UEH and LEH showed a very significant positive correlation (P<0.01), and the rest of the functional traits were relatively stable. Conclusion Four plantations of C. intermedia have formed a transition from the rapid biomass production to the effective nutrient preservation strategy with the increase of age, which results in the mutual regulation and trade-off for adapting to the environmental deprivation in the arid zones.
A Review on the Type Ⅵ Secretion System of Plant Pathogenic Cacteria
XIA Xiong-fei, BO Shu-wen, HAN Chang-zhi
2023, 36(4): 183-192. doi: 10.12403/j.1001-1498.20220398
Objective Type Ⅵ secretion system (T6SS) is one of the regulatory systems that plays important functions in plant pathogenic bacteria. In terms of defense and other aspects, clarifying the T6SS protein and functional differences of important plant pathogenic bacteria will help promote the development and utilization of new pesticides for the prevention and treatment of plant diseases. Method In the study, five kinds of important plant pathogenic bacteria (Pseudomonas syringae, Ralstonia solanacearum, Agrobacterium tumefaciens, Erwinnia amylovora and Xanthomonas oryzae pv. oryzicola) bacterium in 138 conservative T6SS proteins structure domain and genetic relationships were analyzed, and the literatures about the above five kinds of bacteria in the database of the T6SS function research were also analyzed. Results T6SS proteins in the five kinds of plant pathogenic bacteria were different in species and quantity. According to proteins sequence homology and domain, the above proteins could be divided into three categories. Among them, T6SS proteins containing VgrG, HCP and other domains had good clustering discrimination, while T6SS proteins containing TssA, TssG and other domains could be divided into different categories. Conclusion The proteins and function of T6SS in the five kinds of plant pathogenic bacteria have certain conservation and unique characteristics. This study provides a theoretical basis for further prediction and analysis of T6SS proteins in different plant pathogenic bacteria and the relationship between different T6SS proteins.