• Volume 44,Issue 8,2024 Table of Contents
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    • Effect of 2,4-epibrassinolide on the growth and physiological characteristics of common bean seedings under saline and alkaline stresses

      2024, 44(8):1181-1189. DOI: 10.7606/j.issn.1000-4025.20240138

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      Abstract:Abstract 【Objective】In order to explore the physiological mechanism of exogenous 2,4-epibrassinolide (2,4-EBR) in common bean (Phaseolus vulgaris L.) seedlings under saline-alkali stress conditions.【Methods】Using ''Shanxi Red Common Bean'' as the test material, we studied the effects of saline-alkali stress at 100mmol/L (50mmol/LNaCl+50mmol/LNaHCO3, XP), effects of exogenous spraying of 0.1 mg/L 2,4-EBR and 4.0 mg/L Brassinozole (BRZ) on the growth, photosynthetic gas parameters, antioxidant enzyme activity and osmotic adjustment substance content of common bean seedlings , and perform correlation and principal component analysis.【Results】Under saline-alkali stress, common bean leaves curled and withered, and plant height, leaf area, main root length, synthetic pigment content, net photosynthetic rate (Pn), transpiration rate (Tr), and stomatal conductance (Gs) all decreased significantly (P<0.05) , proline (Pro), soluble sugar (SS) content and superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbic acid peroxidase (APX) activities, Relative conductivity (REC), malondialdehyde (MDA) and intercellular carbon dioxide concentration (Ci) were significantly increased (P<0.05). Exogenous spraying of 2,4-EBR can alleviate the wilting and curling of leaves caused by salt-alkali stress, and the plant growth condition gradually improves.?At the same time, it effectively reduces the REC, MDA and Ci of seedling leaves, and significantly increases plant height, leaf area, Primary root length, Pro, SS, Pn, Tr and Gs as well as SOD, POD, CAT and APX activities, but these salt-alkali resistance effects of common beans induced by exogenous 2,4-EBR were reversed after adding BRZ.【Conclusion】 Exogenous 2,4-EBR treatment can reduce membrane lipid peroxidation damage caused by salt-alkali stress by increasing antioxidant system enzyme activity and osmotic adjustment substance content in common bean leaves. It effectively removes the non-stomatal limiting factors that weaken the photosynthesis of common bean seedlings under saline-alkali stress, maintains the photosynthetic activity of the seedlings, promotes seedling growth, and enhances the salt-alkali resistance of common bean seedlings.

    • Induction of innate immune physiological responses in pepper seedlings by chitin and flg22

      2024, 44(8):1190-1200. DOI: 10.7606/j.issn.1000-4025.20230710

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      Abstract:[Objective] To clarify the characteristics of innate immune physiological responses induced by chitin and flagellin-derived peptide flg22 in pepper seedlings, and to explore the relationship between innate immune physiological responses and pepper multiple resistance to diseases. [Methods] Five local pepper cultivars from Sichuan were used as experimental materials in this study. The disease indexes of bacterial wilt and phytophthora blight in pepper seedlings were analyzed. Meanwhile seedlings were cultured by hydroponics and treated with chitin and flg22 exogenously. Among different pepper cultivars, under different induction times, seedling root growth, stomata aperture, callose deposition, reactive oxygen species (ROS) accumulation, SOD, CAT activities as well as the changes of related gene expression were checked . Then the physiological responses and theirs relationship with disease resistance were evaluated comprehensively by using biostatistics.[Results] (1) The results showed that the lowest disease index of bacterial wilt and phytophthora blight was 'CT10' cultivar, was the strongest disease resistance, and the highest disease index of bacterial wilt and phytophthora blight was 'TJ' cultivar, was the weakest disease resistance.(2) Exogenous chitin and flg22 inhibited the root growth rate of pepper seedlings in five cultivars, induced stomatal closure on detached leaves, promoted the accumulations of callose deposition in leaf cell wall, increased ROS content constantly with improved SOD and CAT activities continuously. By calculating the average membership function value of the innate immune physiological response index of each different cultivar, it showed that the highest was 'CT10' and the lowest was 'TJ'. The average membership function value has a significant negative correlation with the disease index of bacterial wilt and phytophthora blight .(3) Exogenous flg22 and chitin induced some innate immune involved genes of 'CT10' seedlings significantly upregulation expressions, like CaWRKY22, CaMAPK7 and ChiIV3.[Conclusion] Exogenous flg22 and chitin induced the innate immune physiological responses in pepper seedlings, and the strength of the responses showed different among different varieties. Based on the membership function, the disease resistance level of pepper varieties was evaluated comprehensively. The results showed the average membership function of 'CT10' was the highest and the multi-resistance level was the best, which was related to the significant up-regulated expression of innate immune involved genes CaWRKY22, CaMAPK7 and ChiIV3.

    • Effect of bagging and shading on the contents of sugar acid and flavonoids in Cerasus humilis

      2024, 44(8):1201-1207. DOI: 10.7606/j.issn.1000-4025.20230757

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      Abstract:【Objective】 To investigate the effects of different light exposure durations and intensities on the sugar, acid, and flavonoid contents of Cerasus humilis fruits, and to provide a reference basis for further exploration of the molecular mechanisms underlying the influence of light exposure on fruit quality. 【Methods】 The C. humilis varieties ''Nongda 6'' and ''Nongda 7'' were used as experimental materials. Fruit bags with three different light transmission rates (30%, 55%, and 100%) were respectively applied during the fruit enlargement period and color conversion period to measure the fruit weight, titratable acid content, soluble solids content, and flavonoid content. 【Results】(1) The single fruit weight and soluble solids content of both varieties were lower during the fruit enlargement period than during the color conversion period, and both decreased gradually with increasing light-blocking rate of the fruit bags. (2) The titratable acid content of ''Nongda 6'' was significantly reduced under bagging treatment, and the higher the light blocking rate of the fruit bag and the longer the bagging time, the more pronounced the reduction in acidity. In contrast, the titratable acid content of ''Nongda 7'' was less affected. (3) The flavonoid content of bagged ''Nongda 6'' was higher than the control, increasing first and then decreasing with the increase in light-blocking rate of the fruit bag, and the content during the fruit enlargement period was higher than that during the color conversion period. The flavonoid content of bagged ''Nongda 7'' was significantly higher than the control only at a 30% light-blocking rate, and the content during the fruit enlargement period was significantly lower than that during the color conversion period. The content increased gradually with the increase in light-blocking rate during the fruit enlargement period, while it first decreased and then increased during the color conversion period. 【Conclusion】 Bagging can effectively improve the sugar, acid, and flavonoid contents of C. humilis fruits. Furthermore, bagging during the fruit enlargement period is suitable for ''Nongda 6'', while bagging during the color conversion period is more effective for ''Nongda 7''. Both varieties show the best overall improvement in sugar, acid, and flavonoid contents with a 55% light-blocking rate on the fruit bag.

    • Diurnal variation characteristics of photosynthesis and chlorophyll fluorescence of six grape varieties at greenhouse in Hotan area

      2024, 44(8):1208-1217. DOI: 10.7606/j.issn.1000-4025.20230735

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      Abstract:[Objective] The diurnal variation characteristics of photosynthesis and chlorophyll fluorescence of greenhouse grape varieties in Hotan area were discussed, and their photosynthetic capacity was comprehensively evaluated, so as to provide reference for the introduction and cultivation management measures of greenhouse grapes in this area. [Methods] Six grape varieties ‘Hutai 8’‘Queen Nina’‘Summer Black’‘Sunshine Muscat’‘Xinyu’ and ‘Crimson Seedless’ were introduced into Hotan greenhouse as experimental materials. The photosynthetic active radiation (PAR), relative chlorophyll content (SPAD), photosynthesis and chlorophyll fluorescence parameters of each variety were measured and analyzed, and the principal component analysis was used to comprehensively evaluate the ability of each table grape variety. [Results] (1) The photosynthetically active radiation of greenhouse in different positions in general shows that before the shed>behind the shed>middle the shed, and the overall performance in different trellis in general shows that on the trellis>middle the trellis>under the trellis. (2) The SPAD values of grape leaves on different trellis was shown as on the trellis>middle the trellis>under the trellis, and the order from high to low among varieties was ‘Crimson Seedless’‘Summer Black’‘Xinyu’‘Hutai 8’‘Sunshine Muscat’‘Queen Nina’.(3) The diurnal variation of Pn、Gs and Tr of each variety showed a bimodal curve, and the diurnal variation of Ci showed a U-shaped and W-shaped variation.Fv/Fo and Fv/Fm generally showed a downward trend and then an upward trend. (4) The photosynthetic capacity of six grape varieties was ‘Crimson Seedless’>‘Summer Black’ >‘Sunshine Muscat’ >‘Xinyu’>‘Hutai 8’>‘Queen Nina’. [Conclusion] ‘Crimson Seedless’ and ‘Summer Black’ have higher Pn、Gs、Tr、Fo、Fm and lower Fv/Fo and Fv/Fm compared to other varieties, and are better adapted to the Hotan area, able to adapt to the local environment of high temperature and highlight intensity facilities.

    • Cloning and Disease Resistance Function Analysis of the Potato Phytosulfokine Gene StPSK4

      2024, 44(8):1218-1228. DOI: 10.7606/j.issn.1000-4025.20240237

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      Abstract:【Objective】 The study aims to provide a theoretical basis for potato disease resistance breeding by investigating the characteristics of the potato defensin gene StPSK4 and conducting a functional analysis of its role in potato disease resistance. 【Methods】 The authors Utilized bioinformatics techniques for a systematic analysis of StPSK4, conducting transcriptome sequencing analysis to study the tissue-specific expression patterns of StPSK4 under biotic and abiotic stress conditions, assessing the plant innate immune responses and sensitivity to Pseudomonas syringae in StPSK4 overexpressing plants. 【Results】 The cDNA full length of the StPSK4 gene was 457 bp, encoding 100 amino acids; StPSK4 contains a signal peptide, with its tertiary structure mainly composed of α-helices and random coils; The C-terminus of PSK4 contains the defensin sequence YIYTQ; StPSK4 shared a high similarity of over 80% with Solanaceae crops; StPSK4 was highly expressed in potato sprouts and petioles, and showed strong responses to abiotic stresses such as high temperature, salt, P. syringae, and Phytophthora infestans. Transgenic potato plants overexpressing StPSK4 had been constructed and obtained. Overexpression of StPSK4 suppressed ROS burst in potato, defensed marker gene expression, and enhanced resistance to P. syringae. 【Conclusion】 StPSK4 was involved in potato stress response and suppressed potato's disease resistance function.

    • A preliminary study on the expression analysis of the BcCHC1 gene in non-heading Chinese cabbage

      2024, 44(8):1229-1238. DOI: 10.7606/j.issn.1000-4025.20230439

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      Abstract:【Objective】 In order to improve TuMV resistance of non-forming Chinese cabbage, the interaction mechanism between BcCHC1 gene and TuMV was investigated. 【Methods】 In this study, a member of the clathrin heavy chain CHC gene family was identified from cabbage and a CHC1 was cloned, and subcellular localization of the CHC1 was performed. CI and 6K2 were screened from the candidate genes by bicolecular fluorescence complementary detection. VIGS induced BcCHC1 silencing and the plants died. BiFC test confirmed the interaction between BcCHC1 and TuMV proteins. 【Results】 The results showed that: (1) BcCHC1 gene was cloned successfully, and its coding sequence length was 5 124 bp, encoding 1 708 amino acids. (2) After 30 days of TuMV infection, the results of real-time fluorescence quantitative PCR showed that the relative expression of BcCHC1 in TuMV inoculated lines decreased significantly. (3) Subcellular localization found that BcCHC1 was located in the cell membrane and nucleus of tobacco epidermal cells. (4) The observation of BcCHC1 gene silenced lines showed that BcCHC1 silenced plants had died before TuMV inoculation. (5) Through BiFC experimental verification analysis, it was found that BcCHC1 could interact with CI and 6K2, and the interaction position with CI was mainly in the nucleus, while the interaction position with 6K2 was mainly in the cell membrane. 【Conclusion】 The study speculated that BcCHC1 interacts with TuMV''s CI and 6K2 to regulate TuMV infection of non-knotting Chinese cabbage by influencing clastrin-dependent endocytosis pathway and viral replication, etc. However, the specific mechanism of BcCHC1 regulating TuMV infection of non-knotting Chinese cabbage needs further study.

    • Cloning, Expression, and Function analysis of MADS-box Transcription Factor CaRIN Gene from Capsicum annuum

      2024, 44(8):1239-1249. DOI: 10.7606/j.issn.1000-4025.20240111

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      Abstract:【Objective】 The study aims to explore the expression characteristics and function of RIN gene of MADS-box, and analyze its impact on the metabolism of carotenoids in pepper. 【Methods】 Based on the transcriptome of pepper fruit development, the full-length CDS of MADS-box transcription factor CaRIN gene related to chili ripening was cloned. Then the bioinformatics, expression patterns, subcellular localization, and transcriptional activation activity were conducted, and the effects of VIGS-induced CaRIN gene silencing on carotenoid metabolism were investigated. 【Results】 (1) The CDS region of CaRIN gene was 732 bp in length. The CaRIN gene encoded a protein containing 243 amino acids with a protein molecular weight of 27.95 kD and an isoelectric point (pI) of 7.06. The CaRIN protein has typical MEF2_ Like MADS domain, belonging to the MICK type transcription factor. (2) CaRIN gene is mainly expressed in flowers and fruits with tissue specificity. CaRIN was located in the nucleus and had transcriptional activation activity. (3) The promoter of CaRIN gene had several hormone response elements such as ABRE, and exogenous ABA and ethephon could accelerate the red turning of fruit and induce the high expression of CaRIN and related genes. (4) After VIGS-induced gene silencing of CaRIN, the expression levels of PSY1, CCS, PDS, CRTZ, LCYB and NCED1 of the carotenoid metabolic pathway genes were decreased by 0.27-0.59 times and the total carotenoid content in fruits (0.379 mg/g) was also significantly decreased compared with the control group (0.650 mg/g). 【Conclusion】 CaRIN may be an important regulatory factor of carotenoid metabolism in capsicum fruit.

    • Identification of CPP Gene Family and Analysis of ExogenousSelenium Response in Foxtail Millet

      2024, 44(8):1250-1260. DOI: 10.7606/j.issn.1000-4025.20240163

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      Abstract:【Objective】To explore the basic characteristics of CPP family members of foxtail millet and their response mode under exogenous selenium treatment, and to provide new genetic materials for the breeding of innovative varieties rich in selenium and high folate in foxtail millet. 【Methods】Using bioinformation tools to identify CPP family members, using qRT-PCR technology to determine CPP gene expression in various organizations and in exogenous selenium, which laid a foundation for revealing the biological function of CPP family and the response mechanism of exogenous selenium in foxtail millet. 【Results】(1) The millet genome contained 9 CPP genes, which were located on 6 chromosomes and were named SiCPP1-SiCPP9 according to the arrangement of genes in chromosomes. Amino acids ranged from 220 to 899, the relative molecular weight ranged from 23624.32 to 97253.16Da, and the isoelectric point ranged from 6.64 to 9.17, the number of introns ranged from 3 to 11, subcellular predictions showed that all family members could position themselves in nucleus. The prediction of the secondary structure of the protein indicated that the proportion of irregular curling and α-helix in the family was the heaviest.. (2) Phylogenetic analysis showed that gluten proteins could be divided into four subfamilies, the number and distribution of conservative elements and structural fields among the same subclans. (3) Promoter analysis revealed a large number of light, growth and development, hormone and stress response elements in foxtail millet CPP family. (4) Fluorescence quantitative results showed that CPP family members were differentially expressed in root, stem, leaf and ear.All 9 members of the millet CPP family were responsive to exogenous selenium, among which SiCPP5, SiCPP6, SiCPP7 and SiCPP8 were the most responsive. 【Conclusion】Members of the millet CPP family had tissue expression specificity and varying degrees of response to exogenous selenium.

    • QTL mapping and Candidate Gene Identify of Seed Glucosinolate Content in Brassica napus

      2024, 44(8):1261-1272. DOI: 10.7606/j.issn.1000-4025.20240120

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      Abstract:【Objective】To explore the genetic loci and candidate genes of glucosinolate content in Brassica napus, 【Methods】 The phenotype data for glucosinolate content of a double haploid (DH) population named KN population was surveyed in the year 2013-2017 for QTL mapping and identification of candidate genes using composite interval mapping by Wincart 2.5 software based on the high-density SNP genetic linkage map. 【Results】A total of 47 identified QTLs for glucosinolate content were detected, individual QTLs could explain 2.48%–19.63% of the phenotypic variation, of which qGC.16YL19-4 was the maximum phenotypic variation of 19.44% and qGC.15YL12-5 was the minimum phenotypic variation of 1.82%. 47 identified QTLs were integrated into 38 consensus QTL by meta-analysis. Seven environment stable expression QTLs (cqGC.A9-5, cqGC.A9-7, cqGC.A9-9, cqGC.C2-9, cqGC.C2-10, cqGC.C9-5 and cqGC.C9-6) for glucosinolate content were identified, including three major QTLs (cqGC.A9-5, cqGC.C2-10 and cqGC.C9-5). Three candidate genes (BnaA09g05480D, BnaC09g05620D and BnaC09g05810D) within major QTL confidence interval were identified, which were located in two major QTL regions. Based on their annotation, these candidate genes involved in the biosynthetic pathway of glucosinolates (the biosynthesis of IAOx and isomerization of 2-alkyl malic acid to form 3-alkyl malic acid ester) and transport and distribution of glucosinolates. 【Conclusion】 Three major QTLs for glucosinolate content and three candidate genes were identified, these results lay the provide theoretical basis for functional analysis of genes and the cultivation of fine quality rapeseed varieties in the future.

    • Characterization of repetitive sequences in Leymus secalinus and chromosomal distribution in related species

      2024, 44(8):1273-1282. DOI: 10.7606/j.issn.1000-4025.20230751

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      Abstract:[Objective] Leymus Hochst stands as a crucial genetic resource for the genetic improvement and breeding of cereal crops. However, as allopolyploids, their genome origin remains unclear. [Methods] Genomic Cot-1DNA library of Leymus secalinu was constructed, clones of which were sequenced and analyzed. A few of repetitive sequences were physically mapped in chromosomes of L. secalinus, L. racemousus, and Psathyrostachy juncea by Fluorescence in situ hybridization (FISH). [Results] (1)The repetitive sequences of the Cot-1DNA of L. secalinus could be classified into 4 types based on their expected genomic distribution patterns, tandem repeats (TaiI, Lt1-6, pTa535 and pSc250 family), dispersed repeats (retrotransposable LTR and transposable elements), tandem mixed dispersed repeats (LTR plus Afa-family and N8-family plus LZ-NBS-LRR), and uncharacterized repeats, and which represented 32.4%, 45.7%, 12.4% and 9.5% of the Cot-1DNA, respectively. (2) The hybridization sites number of tandem repeats TaiI, Lt1-6, pTa535 and pSc250 were highly varied from 7-20, 1-14, 17-26 and 0-24 respectively, across different species and accessions. (3) Ten LTR repeats hybridized the tested species chromosomes mainly by 3 patterns: First, hybridizations distributed in centromere, pericentromere, and intercalary regions in all chromosomes. Second, hybridizations were all over the chromosomes. Third, Hybridizations were as the same as the pattern 1 except a few chromosomes carrying telomeric hybridizations. Two LTR/copia sequences were detected only in L. secalinus, while the others were detected in all tested species and accessions but with polymorphisms in hybridization intensities or hybridization patterns in partial chromosomes. [Conclusion] The results suggested rather fast-evolving repetitive sequences in Leymus genome, and supported hypothesis that the dispersed elements must have spread across genomes, thus homogenizing the nuclear genomes of Leymus during the allopolyploidization process.

    • Construction and phenotypic analysis of EMS mutant library of seed-used pumpkin (Cucurbita pepo L.)

      2024, 44(8):1283-1294. DOI: 10.7606/j.issn.1000-4025.20240121

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      Abstract:【Objective】To accelerate the innovation process of germplasm resources of seed-used pumpkin by constructing a mutant library, which is of great significance for variety selection, improvement and broadening of the genetic base. 【Methods】 Ethyl methanesulfonate (EMS), a 1.8% mutagen, was used to treat ZHL4 seeds of seed-used pumpkin for 15h. Then, phenotypic variation was observed in single plants of the M1 and M2 generation populations, and microstructural observation was made on the mutant strain ZHL4-33 of the M2 population. 【Results】 (1) A total of 242 mutant plants with 45 phenotypic variations were screened in the M2 population, and the types of variation covered all growth periods and plant organs of the mutant plants, with a total mutation frequency of 25.17%. (2) The leaf microstructure showed that the thickness of the fenestrated tissue of the mutant was significantly higher than that of the wild type, the arrangement was compact, and the traces of the vascular layer were obvious; the stem microstructure showed that the vascular bundles of the mutant were more and densely packed, the diameter of the conduit was smaller than that of the wild type, and the pith was well developed, with a small cell gap and an increase in the number of cells. 【Conclusion】 A mutant library of 425 M2 lines has been constructed, which lays a material foundation for the study of the functional genome of seed-used pumpkin and the selection and breeding of new varieties of seed-used pumpkin.

    • Allelopathic effects of leaf extracts from economic forests on the growth of Fabaceae and Poaceae pasture grasses

      2024, 44(8):1295-1304. DOI: 10.7606/j.issn.1000-4025.20240059

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      Abstract:Abstract 【Objective】 Allelopathy is one of the main factors affecting understory grass growth, and the chemosensitivity effects of fading leaves of Ziziphus jujuba, Juglans regia and Malus pumila in northern Shaanxi are not yet clear. 【Methods】 Outdoor Medicago sativa and Lolium perenne potting experiments were carried out by setting up different concentrations of Z. jujuba, J. regia and M. pumila withered leaf extracts (concentrations of 0.1, 0.05, 0.025 and 0.0125 g/mL).【Results】 (1) The biomass of both forages was significantly reduced under the J. regia and M. pumila leachate treatments, with L. perenne having only 0.45 g fresh weight per plant, Compared to the control group, the M. sativa only had 4.70 g. Plant height first increased and then decreased with increasing concentration of the leaching solution (P < 0.05). (2) The content of malondialdehyde in M. sativa and L. perenne treated with different extracts was higher than that in the control group. The biochemical indicators of the two grasses showed significant differences in different types of extracts (P < 0.05). (3) J. regia and M. pumila extracts showed significant differences in root traits of M. sativa and L. perenne (P < 0.05). 【Conclusion】 The biomass of M. sativa and L. perenne respond differently to different extracts, exhibiting an "increase or decrease" effect, The treatment of Z. jujuba extract is more suitable for the growth of L. perenne, and the interaction between M. sativa and L. perenne, and economic forests should be fully considered.

    • Anatomical Study of Nectar Gland Development and Changes in Sugar Content in Caucasian Clover (Trifolium ambiguum Bieb. )

      2024, 44(8):1305-1311. DOI: 10.7606/j.issn.1000-4025.20230847

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      Abstract:【Objective】Caucasian clover (Trifolium ambiguum Bieb.) is an excellent nectar source plant, and understanding the morphological characteristics, tissue structure, and development was critical for its reasonable utilization.【Methods】Well-grown standard plants of Caucasian clover were selected and sampled at different developmental periods of the florets, i.e., flower bud visible, petal visible, floret with white petal, floret with pink petal, and floret withered. The paraffin sectioning technology was used to observe the cell and tissue structure of the florets. The starch and soluble sugars including sucrose, fructose, and glucose were determined by capillary aspiration and physiological kit and spectrophotometry at the flower bud visible, petal visible, floret with white petal, floret with pink petal, and floret withered. 【Results】The results showed that: (1) The nectar amount of a individual floret was 0.394±0.095 μL, and the nectar amount per meter square was 4536.93±1319.34 μL. (2) The stamens nectar gland was located at the base of the inner filament of the 9-stamen-combined. The nectar gland tissue had obvious dynamic changes in the starch granules during the whole honey secretion process after PAS staining, which evidenced it was the amyloid nectar gland. (3) The soluble sugar content of floret was the highest at floret with pink petal stage with 7.978 mg/g. Fructose accounted for the largest proportion among the soluble sugar category, peaked at the floret with white petal stage with 66%, decreased gradually after this stage. The starch content accounted for 81%~82% of the total soluble sugar content with a maximum value of 35.173 mg/g at the floret with pink petal stage and the minimum value of 24.168 mg/g at floret with white petal stage. 【Conclusion】The nectar glands of the Caucasus clover belong to the stamens nectar glands, which are composed of secretory epidermal cells and nectar cells. The raw honey is provided by the vascular bundles adjacent to the nectar glands, processed into honey by the nectar gland cells, and finally secreted from the stomata of the epidermis. The soluble sugar content of Caucasus clover florets was the highest in the full flowering stage, and the proportion of fructose was the largest.

    • Comparison of the Leaf Epidermal Micromorphology between Female and Male Idesia polycarpa Maxim.

      2024, 44(8):1312-1320. DOI: 10.7606/j.issn.1000-4025.20240070

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      Abstract:【Objective】The study aimed to explore the micromorphological characteristics of leaf epidermis of Idesia polycarpa Maxim. and compare differences between the female and male plants, and provide references for the mining and utilization of this germplasm resources. 【Methods】The leaf epidermal micro-configurations of 40 plants of I. polycarpa (half female and half male) were characterized with scanning electron microscopy. Meanwhile, 12 stomatal traits were measured, and the similarities and differences among samples were analyzed. 【Results】(1) The leaf epidermal hair, cell morphology, stomatal characteristics and wax pattern of both female and male I. polycarpa were similar. Its dense, conical conicoid-like wax covered on the abaxial epidermis was rarely observed in other plants. (2) The leaf stomatal size (length, width, area and perimeter) and density related parameters of female I. polycarpa were slightly higher than those of male samples. On the contrary, leaf stomatal pore related parameters (stomatal pore width, stomatal opening area and stomatal opening level) were slightly higher in male samples. But all differences were not statistically significant (P > 0.05). (3) Most stomatal traits were significantly correlated with each other, while stomatal density was rarely related with others and was supposed to be genetically regulated independently. 【Conclusion】The present study firstly expounded the leaf epidermal micromorphological characteristics of I. polycarpa, and indicated that the conical conicoid-like wax pattern could be used as a key basis for germplasm evaluation, and the stomatal parameters were of great significance for gender determination of its young seedlings.

    • Meiotic observation on ‘Bartzella’, an intersectional hybrid of Paeonia

      2024, 44(8):1321-1330. DOI: 10.7606/j.issn.1000-4025.20240092

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      Abstract:[Objective] Most intersectional hybrids in Paeonia are triploids and generally sterile, producing few hybrid offsprings. Observing the meiotic chromosome behaviors of ‘Bartzella’, an intersectional hybrid with good ornamental value and a few hybrid offsprings, can provide insight into the formation mechanism of its extremely low fertility. [Methods] The study utilized the anthers of ‘Bartzella’ as materials to observe the meiotic chromosome behaviors of pollen mother cells (PMCs) through the squash method. [Results] (1) In metaphase I, a large number of univalents were formed in ‘Bartzella’ PMCs. In anaphase I, various types of chromosomal aneuploid segregation were observed, accounting for up to 89.13% of the total. (2) During the first meiotic division, chromosome bridges and fragments were found in 27.20% of the PMCs; during the second meiotic division, this percentage increased to 47.68%. (3) In metaphase Ⅱ spindle positioning abnormalities were relatively common, with fused spindles accounting for 27.06% and tripolar spindles accounting for 12.84%. The meiotic products included up to 72.40% of dyads and 13.43% of triads, which could generate unreduced gametes accounting for about 67%. [Conclusion] Chromosome aneuploidy segregation and loss of chromosome segments during meiosis may be the primary causes of the high sterility of ‘Bartzella’. Fused spindles, tripolar spindles, and abnormal cytokinesis at the end of second meiotic division may result in the production of unreduced gametes. The significant number of unreduced gametes might give ‘Bartzella’ the potential for polyploid breeding. However, interploidy hybridization barriers could restrict its hybrid affinity.

    • >New Plant Taxa
    • Gastrodia exilis Hook.f., A New Record of Orchid Species from SW China, and Comparative Morphology of Its Close Relevant Species

      2024, 44(8):1331-1337. DOI: 10.7606/j.issn.1000-4025.20240024

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      Abstract:[Objective] A newly recorded orchid species from Yunnan province, SW China, Gastrodia exilis Hook.f. is spotted, and the main characters of its morphologically close relatives G. menghaiensis Z.H. Tsi & S.C. Chen, G. putaoensis X.H. Jin and G. dyeriana King & Pantl. are compared, discussed, and summarized. [Methods] Morphological and anatomical observations of wild population specimens of the above species were carried out using a stereomicroscope, and photographs were taken with a close-up lens attached digital camera. [Results] Results show that the species can be easily distinguished from those species by having a lip free of perianth tube, disk with two conspicuous triangular lamellae near apex, and lobes of perianth tube crisped. [Conclusion] G. exilis Hook.f. is a newly recorded orchid species in China, the discovery expands its distribution area and further enriches the resources of wild orchids in China.

    • The genus Schistochila (Schistochilaceae, Marchantiophyta) in Guangxi, with a new record Schistochila sciurea for China

      2024, 44(8):1338-1344. DOI: 10.7606/j.issn.1000-4025.20240067

      Abstract (233) HTML (0) PDF 7.31 M (613) Comment (0) Favorites

      Abstract:[Objective] The study aimed to understand the actual distribution of the species of Schistochila in Guangxi, should not only add new data for the study of bryophytes in Guangxi, but also add necessary basic data for the protection of bryophyte diversity in China. [Methods] Through the recent field survey and checking specimens of Schistochila from Guangxi Herbarium (IBK), the species diversity were determined by morphological observation and relevant literature review. [Results] Ten specimens of Schistochila from Guangxi were found, and three species of Schistochila in Guangxi were finally confirmed, namely, Schistochila aligera (Nees & Blume) J.B. Jack & Steph., S. blumei (Nees) Trevis. and S. sciurea (Nees) Schiffn. [Conclusion] Schistochilaceae and Schistochila were here reported as new records to Guangxi at the levels of family and genus, respectively. Here, Schistochila sciurea was firstly reported to bryoflora of China. Detailed description of Schistochila sciurea and main diagnostic characters of S. aligera and S. blumei were provided based on the studied specimens. Each species was also accompanied by vouchers, distribution information and a color plate.