Abstract:In order to study the effects of HDACs (histone deacetylation) in winter rapeseed(Brassica rapa L.) under low temperature stress, with strong cold resistance varieties of ‘Longyou 7’, low temperature resistance varieties of ‘Tianyou 4’ and weak cold resistance varieties of Lenox, winter rapeseed as materials, we analyzed HDACs inhibitor trichostatin A (TSA) postpartum seed germination, low temperature stress antioxidant enzyme activity and osmotic adjustment substances content changes, and identified the genetic family of HDACs in the genome and analyzed its expression characteristics in different cold winter rapeseed varieties. The results show that: (1) both 1 and 3 μmol/L TSA have inhibit effect on the root length of three varieties, and the exogenous spray TSA at different temperatures increased antioxidant enzyme activities and osmotic adjustment substance contents. (2) In this study, a total of 21 HDACs members in winter rapeseed were identified, system development result showed that HDACs were divided into three subfamilies, the chromosome location found that all gene were distributed unevenly on eight chromosomes, with no gene distribution on chromosomes 7 and 8. The HDACs promoter sequence contains many cisacting elements that related to stress response, light response and hormones response. (3) The results of different tissue sites showed that most genes were significantly higher in shoot apical meristem than in other tissues. BrapaHDA19, BrapaHDA61, BrapaHDA8 and BrapaHDA72 were high in winter rapeseed, BrapaHDA52 ‘Tianyou 4’ stem leaf, silique, basal leaf (new) and basal leaf (old) have higher expression, and BrapaHDA72 is high in lenox flowers. (4) Low temperature stress expression results showed that BrapaHDA8, BrapaHDA14, BrapaHDA2, BrapaHDT22 and BrapaHDA151 showed differentially expressed in three cold resistance different materials. Inference by the above results, these genes may play an important role in the growth and cold resistance in winter rapeseed.

Abstract:Cassava (Manihot esculenta Crantz) is an important food crop and cash crop in tropical and subtropical regions. UDPglycosyltransferases (UGTs) belongs to glycosyltransferases, which is found in all plant species. In this research, Manihot esculenta cv. SC124 was regarded as material, and the MeUGT41 gene was cloned by RTPCR and its function in cassava bacterial blight resistance was analyzed. These research provided clues for further study on the mechanism of MeUGT41 gene in cassava resistance to biotic stress. The results showed that: (1) the expression of MeUGT41 gene was significantly induced by Xamthomonas axonopodis pv. Manihotis (Xam). (2) Virus induced gene silencing (VIGS) vector of MeUGT41 gene was constructed. Through gene silencing in cassava leaves, qRTPCR results showed that MeUGT41 gene was significantly decreased in cassava leaves. (3) Subsequently, Xam infection experiments were carried out on cassava leaves, and the results showed that the downregulation of MeUGT41 gene expression significantly reduced the resistance to Xam infection.

Abstract:To explore the target relationship between hrhmiR319e and transcription factor AP4 of sea buckthorn, and analyze their expressional changes in developing seeds, we selected the seeds at different developmental stages as study materials and used RNA hybrid software to predict the binding sites in the 3′UTR region of the candidate target gene AP4 by miR319e seed mature sequence. The pcDNA3.1+pmirGLOAP4 and pcDNA3.1hrhmir319e+pmirGLOAP4 vectors were constructed respectively. The method of double luciferase reporter gene detection was used to verify whether miR319e could target the 3′UTR region of candidate target gene AP4, and the expression changes of miR319e and AP4 were analyzed using realtime fluorescent PCR technology in developing sea buckthorn seeds. The results showed that: (1) AP43′UTR region and miR319e seed mature sequence were completely complementary. (2) The plasmid vector of pcDNA3.1hrhmir319e+pmirGLOAP4 can significantly inhibit the luciferase activity (P< 0.001). (3) In developing seeds, the changes of hrhmiR319e expression level showed a trend of increasing at first and then decreasing, while the changes of AP4 gene expression level first decreased and then increased. When hrhmiR319e expression reached its highest level at 80 d after flowering, it was 3.146 in ‘Xine 3’, 4.298 in ‘Suiji 1’ and 3.892 in ‘Za 56’, respectively; but the expression level of AP4 gene had the lowest value, it was 0.427 in ‘Xine 3’, 0.526 in ‘Suiji 1’ and 0.451 in ‘Za 56’, respectively. Thus, sea buckthorn hrhmiR319e could target the 3′UTR region of AP4 gene, and there is negatively regulative relationship between them. These data provided scientific references for further understanding the seed development mechanism of sea buckthorn and the cultivation of large seed varieties.

Abstract:Dtype cyclin regulates the G1/S transition of the cell cycle and plays an important role in the growth and development of plants. Transgenic poplar PtoCYCD2;1 (OEPtoCYCD2;1) plants showed obvious phenotypic changes, with reduced plant height, thinner stems and curled leaves. Using transgenic poplar OEPtoCYCD2;1 as the research material, the study analyzed the function of PtoCYCD2;1 in plant growth and development by linking plant phenotypes to transcriptomics sequencing and physiological index changes. This study provides a theoretical basis for the functional study of Dtype cyclins in woody plants. Studies have shown that: (1) a total of 1 269 differentially expressed genes were identified in OEPtoCYCD2;1, of which 700 were upregulated and 569 were downregulated. Through analysis, it was found that 26 genes belonging to AP2/ERF transcription factors were upregulated; 8 downregulated differentially expressed genes were enriched in the xylem synthesis pathway; a total of 27 downregulated differentially expressed genes were enriched in the carbon metabolism pathway. In the carbon metabolism pathway, 8 genes were enriched in the Calvin cycle pathway. (2) The results of qRTPCR experiments showed that the qRTPCR results of 9 differentially expressed genes were consistent with the trend of expression levels determined by RNAseq, indicating the reliability of the RNAseq results. (3) Physiological index analysis showed that compared with wild type (WT), the total chlorophyll content of young and mature leaves of transgenic poplar OEPtoCYCD2;1 increased by 57.36% and 78.22%, respectively; and the soluble sugar content of mature leaves decreased by 12.72%; and the lignin content in young and mature leaves decreased by 4.48% and 8.03%, respectively and the lignin content in young and mature stems decreased by 20.03% and 31.63%, respectively. This study indicated that transgenic poplar OEPtoCYCD2;1 affects the expression of related genes in the carbon metabolism and lignin synthesis process of poplar, thereby reducing the contents of corresponding metabolites in transgenic plants, eventually leading to changes in plant phenotype and overall biomass reduction.

Abstract:NADPmalate enzyme (NADPME) is a key photosynthetic enzyme in C₄ plants and plays an important role in biotic and abiotic stress. To further study the function of NADPME, we cloned the NADPME family gene sequences from the leaves of C₃C₄ species Salsola laricifolia, and then determined the expression patterns in tissues under different abiotic stresses. We also cloned NADPMEs promoter sequences and analyzed the element differences in response to abiotic stress based on bioinformatics software. The results showed that: (1) three NADPMEs were obtained, named SaNADPME1, SaNADPME2 and SaNADPME4, with the length of CDS sequence was 1 755 bp, 1 758 bp and 1 941 bp, respectively. (2) SaNADPME1 was mainly expressed in roots, while SaNADPME2 and SaNADPME4 were mainly expressed in leaves. Under the stress of ABA, NaCl, NaHCO₃ and PEG₆₀₀₀, three NADPMEs could be induced to express in Salsola laricifolia, and the response expression patterns of SaNADPME4 and SaNADPME2 were similar. (3) The length of promoter regions of SaNADPME1, SaNADPME2, and SaNADPME4 were 2 351 bp, 1 655 bp and 2 887 bp. Bioinformatics analysis showed that they contained not only basic promoter elements, but also elements in response to stress response.

Abstract:The application of cytoplasmic male sterile (CMS) line can effectively improve hybrids quality. In this study, the LncRNAs related to cytoplasmic male sterility in broccoli were identified by Illumina sequencing, and their target genes and expression characteristics were also analyzed. Meanwhile, the expression patterns of 16 randomly selected LncRNAs were detected by qRTPCR technology, which could provide new insights for further clarifying the mechanism of occurrence of male sterility involved by LncRNAs in broccoli. The results show that: (1) 4 326 LncRNAs related to male sterility were identified in broccoli. Among them, 37 LncRNA were differentially expressed between male sterility line and its maintainer. (2) 370 cistarget genes of these differentially expressed LncRNA were predicted, many of these target genes were transcription factors and bioproteins related to CMS. (3) XLOC_006651, XLOC_016660, XLOC_003494 and XLOC_013121 were highly expressed in early development stage of bud in male sterile line and its maintainer line, and then decreased gradually with development of bud; XLOC_021769 and XLOC_038964 showed a fallingrising expression pattern. And their expression were higher in male sterile line than that in maintainer line at different development stages of bud. (4) All sixteen LncRNA could be detected in pedicel, calyx, petal, stamen and pistil. XLOC_038964, XLOC_011575, XLOC_013157, XLOC_039677, XLOC_037356, XLOC_034182 and XLOC_017574 showed similar expression patterns, with low expression in stamen and pedicel, higher expression in calyx and petal, and the highest expression in pistil.

Abstract:Cyperus esculentus is a new economic crop for both oil and grain worldwide. However, no relevant studies was reported on C. esculentus accessions in China. In order to clarify the main biological related traits, we selected three typical tubers, ‘Yuyousha 3’ (mediumlong), ‘Yuyousha 2’ (mediumround) and ‘YYS4’ (large), of C. esculentus and treated with single plant. The root tip cells of C. esculentus in mitotic phase were treated by DAPI(4′,6diamidino2phenylindole) staining and fluorescence in situ hybridization with a telomere DNA probe to analyze chromosome numbers in the cells. The results showed that: (1) three yield relative traits, tiller, single tuber weight and number of tuber per plant were showed extremely significant difference among materials. Among them, the single tuber weight of ‘YYS4’ (1.98 g) was the 3.3 and 5.4 times compared with that of ‘Yuyousha 2’ (0.61 g) and ‘Yuyousha 3’ (0.37 g). The number of tubers per plant of ‘Yuyousha 3’ was 245, which were the 1.3 and 1.6 times that of ‘Yuyousha 2’ and ‘YYS4’ respectively. ‘Yuyousha 3’ has the highest tiller number, which were 2.1 times that of ‘Yuyousha 2’ and 1.5 times that of ‘YYS4’. (2) The quality indexes of the three materials were significantly different. ‘Yuyousha 2’ showed highest oil content (32.00%), the soluble sugar content of ‘Yuyousha 3’ (21.30%) was the highest, and the starch and protein content of ‘YYS4’ was the highest. (3) ‘Yuyousha 2’ showed the leaves net photosynthetic efficiency (18.17 μmol·m^-2·s^-1) was the highest, the transpiration rate was relatively lower, and the water use efficiency was the highest among the three materials. (4) The chromosome numbers of the 3 materials were the same, all 156, and the results of DAPI staining and telomere probe fluorescence in situ hybridization were completely consistent. The results can provide a reference for subsequent breeding utilization, karyotype analysis and genetic classification.

Abstract:A diatom species is identified as Amphipleura pellucida (Kützing) Kützing during the study of diatom classification and diversity in the Wuling Mountains. The results demonstrate that A. pellucida possesses the following features: (1) spindleshaped valve outlines; (2) long and straight central sternum; (3) short raphe system only located next to two poles; (4) stria density 38-39/10 μm and areola density 54-58/10 μm; (5) external proximal raphe endings straight and distal raphe endings slightly dilated; (6) the internal areola openings occluding by hymenes. The results of this study provide clear ultrastructure pictures and scientific descriptions for A. pellucida.

Abstract:Selenium (Se) stress usually hinders plant growth by inducing cell injury. Cinnamaldehyde (CA) is a kind of natural chemical with antioxidative properties. In this study, we used physiological, biochemical, and in situ fluorescence detection approaches to study the role of CA in the alleviation of Seinduced phytotoxicity in the roots of nonheading Chinese cabbage (Brassica rapa) seedlings, which might involve in the regulation of polyamine oxidasehydrogen peroxide (PAOH₂O₂) system. Basically, we obtained the following results. (1) Se stress significantly inhibited root growth in a dosedependent manner. The addition of CA remarkably alleviated the root growth inhibition caused by Se stress. (2) CA alleviated root oxidative damage and cell death induced by Se stress. (3) Se stress led to a significant increase in PAO activity and H₂O₂ level. The addition of CA significantly decreased PAO activity and H₂O₂ level. (4) Among the six BrPAOs family genes (BrPAO16) in B. rapa，Se stress significantly upregulated the expression levels of BrPAO3, BrPAO5 and BrPAO6, an effect that was reversed by the addition of CA. These results suggested that CA was able to alleviate Seinduced phytotoxicity by repressing PAOH₂O₂ system. The results provide new evidence for exogenous regulation of Se tolerance in crops.

Abstract:Sorghum seedlings of ‘longza 19’ were inoculated with Rhizoctonia solani AG1IA. We investigated the growth and physiological and metabolic indexes of sorghum seedlings at different infection times through pot experiment, so as to reveal the effects of R. solani infection on sorghum growth, osmotic regulatory substances and antioxidant enzyme activities. The results showed that: (1) the plant height, root length, aboveground (stem and leaf) fresh and dry mass, underground (root) fresh and dry mass of sorghum seedlings decreased with the extension of inoculation time, which decreased by 41.0%, 29.2%, 50.0%, 50.0%, 53.3% and 50.0%, respectively compared with the control at 72 h after inoculation. (2) The chlorophyll a content of seedling leaves decreased significantly by 45.3% compared with the control 72 h after inoculation, and the maximum photochemical efficiency (F_v/F_m) of PSⅡ decreased gradually with the increase of inoculation time. (3) The contents of MDA and O₂^-· and H₂O₂ in seedling leaves increased gradually with the increase of inoculation time, and increased significantly by 244.6%, 140.4% and 137.0% compared with the control 72 h after inoculation; The activities of SOD, POD, APX and CAT in leaves changed differently after inoculation, but increased significantly by 16.5%, 60.3%, 50.0% and 36.5% compared with the control at 72 h. (4) The contents of soluble protein and soluble sugar in seedling leaves increased gradually with the increase of inoculation time, and reached a significant level at 24-72 h; It was found that inoculation with R. solani could cause disease spots in sorghum seedlings, excessive accumulation of reactive oxygen species and significant oxidative damage to membrane; In the early stage of infection, sorghum plants mainly accumulate more osmoregulation substances to resist the damage caused by R. solani. In the later stage of infection, the damage is aggravated with the plant, and the activities of antioxidant enzymes are significantly enhanced, so as to maintain the steadystate balance of reactive oxygen species metabolism in sorghum and reduce the further oxidative damage of plant membrane.

Abstract:Oat cultivar ‘Yanke 2’ was used as experimental material. Four treatments, namely normal water supply (CK), spraying humic acid soluble fertilizer (CKH) under normal water supply, severe drought stress (SS) and spraying humic acid soluble fertilizer (SSH) under severe drought stress, were set in pot. We determined reactive oxygen species (ROS) level, antioxidant enzyme activity, total antioxidant content and yield in oat leaves to clarify the regulation effect of humic acid watersoluble fertilizer (HA) on ROS scavenging system in oat leaves under severe drought stress, and to explore the effect of HA on drought tolerance of oat and its mechanism. The results show that: (1) compared with CK, the contents of superoxide anion (O₂^-·), hydroxyl radical (·OH), hydrogen peroxide (H₂O₂) and malondialdehyde (MDA), as well as the activities of superoxide dismutase (SOD) and peroxidase (POD) in oat leaves were significantly increased under severe drought stress, and all of them were significantly decreased after spraying HA. However, the level of active oxygen was still significantly higher than CK (P<0.05). (2) Compared with CK, the activities of catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR) and glutathione peroxidase (GPX) in oat leaves were significantly decreased under severe drought stress, while the total antioxidant capacity (TAOC) was significantly increased after spraying HA, but the activity of each enzyme was still lower than CK (P<0.05). (3) Compared with CK, the grain yield and biological yield of oat were significantly decreased under severe drought stress, and significantly increased after spraying HA, but still significantly lower than CK (P<0.05). In conclusion, spraying HA under severe drought stress can effectively improve the antioxidant enzyme activity of oat leaves, promote renewable antioxidants, enhance the total antioxidant capacity, thereby effectively remove caused severe drought stress accumulation of reactive oxygen species, reduce oxidative damage of severe drought stress on plant cell membrane, eventually relieve severe drought stress to the harm of oats, make up for the loss of grain yield to a certain extent.

Abstract:In this study, we used ‘Ningjing No. 6’ as the material, treated with exogenous fulvic acid (FA) and auxin inhibitors to explore the effect of FA on root growth and its relationship with auxin. The results showed that: (1) after treatment of rice seedlings with 50~800 mg·L^-1 FA for 6 days, when the concentration of FA exceeded 100 mg·L^-1, the root elongation was significantly promoted; when the concentration of FA exceeded 400 mg·L^-1, the average lateral root length and lateral root density of rice in FA treatment group increased significantly compared with the control. (2) Compared with the control, lowconcentration FA treatment had no significant effect on the content of auxin in the root tips of rice seedlings, but 400 mg·L^-1 FA treatment significantly increased the content of endogenous auxin in the root tip of rice seedlings. (3) 3 μmol·L^-1 auxin synthesis inhibitor 4biphenylboronic acid (BBo), 4phenoxyphenylboronic acid (PPBo) or 30 μmol·L^-1 auxin signal transduction inhibitor pchlorophenoxy isobutyric acid (PCIB) treatment significantly inhibited the growth of rice roots and the occurrence of lateral roots; 1 μmol·L^-1 auxin polar transport inhibitor triodobenzoic acid (TIBA) treatment significantly inhibited the elongation and growth of rice roots and the occurrence of lateral roots, but has no significant effect on the lateral root length. (4) The cotreatment of FA with BBo or PPBo could significantly inhibit the promotion of FA on rice root elongation and lateral root formation. TIBA and PCIB treated rice together with FA could inhibit the promotion of FA on the growth of roots. In addition, PCIB could repress the promotion of FA on lateral root development, but TIBA has no significant effect. These results indicate that exogenous FA may regulate root elongation and the development of lateral roots by regulating the synthesis, polar transport or signal transduction of endogenous auxin.

Abstract:In this study, we treated the seedlings of Ardisia gigantifolia by 8 different light qualities, red light (R), blue light (B), red∶blue=2∶1 (R₂B₁), red∶blue=4∶1 (R₄B₁), red∶blue=6∶1 (R₆B₁), red∶blue=8∶1 (R₈B₁), purple light (P) and green light (G), and with natural light as control (CK), to explore the response of growth and development of A. gigantifolia to different light quality, to improve the quality of seedlings and the content of medicinal ingredients, providing reference for the cultivation and protection of precious medicinal plants. The results were as follows: (1) the height of seedling was reached the maximum value under R treatment, while the ground diameter, fresh weight and dry weight were reached the highest maximum values under R₂B₁ treatment. (2) Chlorophyll content in the leaves of A. gigantifolia was the highest under B and the lowest under G treatment. Chlorophyll and carotenoid contents increased gradually with the increase of blue light ratio in redblue composite light. (3) The contents of malondialdehyde (MDA) and free proline were the highest under G treatment, and the activities of superoxide dismutase (SOD) and peroxidase (POD) were improved under B treatment and appropriate proportion of red and blue combined light treatment. (4) Different treatments had significant effects on chlorophyll fluorescence parameters of A. gigantifolia. The highest values of maximum photochemical efficiency(F_v/F_m) and effective photochemical efficiency ［Y(Ⅱ)］ were in the treatment of R₂B₁, and the highest value of photochemical quenching coefficient (qP) was in the treatment of B, but there was no significant difference with R₂B₁. The nonphotochemical quenching coefficient (NPQ) was higher in R₈B₁ and G treatment, and there was no significant difference between them. (5) Although the content of saponins was the highest under B treatment, the R₂B₁ treatment was more beneficial to improve saponins yield per plant. (6) It was concluded that R₂B₁, B and R₄B₁ were significantly better than CK, and R₂B₁ treatment was the best beneficial to improve the quality and content of active components of A. gigantifolia, shorten the incubation period, and achieve efficient production and utilization.

Abstract:To explore the critical period and key enzymes of organic acid accumulation, and reveal the cause of low acid in fruit, we used the ‘Golden Delicious’ apple and its excellent strain (SGP1) as materials to determine the components and contents of organic acids and the activities of metabolismrelated enzymes during fruit development, then analyzed their variation law and correlation. The results showed that: (1) during the fruit development, the content of organic acids in ‘SGP1’ was significantly lower than that of ‘Golden Delicious’, which was only half of that of ‘Golden Delicious’ at maturation stage. The organic acids of ‘SGP1’ were mainly composed of malic acid, quinic acid, tartaric acid and citric acid, with quinic acid as the main component at young fruit stage and malic acid as the main component at maturation stage. (2) The malic acid content of ‘SGP1’ was significantly lower than that of ‘Golden Delicious’, whose variation law was opposite to that of ‘Golden Delicious’ at young fruit stage and fruit enlargement stage, and the critical accumulation stage and rapid decline stage were earlier than that of ‘Golden Delicious’. The change trend of other acid components in ‘SGP1’ and ‘Golden Delicious’ was basically the same, and the acid content at young fruit stage of ‘SGP1’ was significantly higher than that of ‘Golden Delicious’, while there was no significant difference at maturation stage. (3) The activities of malic acid metabolismrelated enzymes in ‘SGP1’ were significantly higher than those in ‘Golden Delicious’ at young fruit stage, and were equal to or significantly lower than those in ‘Golden Delicious’ at maturation stage; The changes of MDH activity in young fruit stage and ME activity in maturation stage of‘SGP1’and ‘Golden Delicious’ were opposite. (4) Correlation analysis showed that the malic acid accumulation of ‘SGP1’ in young fruit stage was extremely significantly positively correlated with PEPC and VHA, while there was an extremely significantly negative correlation between the malic acid accumulation and activities of MDH, PEPC and VHA in ‘Golden Delicious’. At fruit enlargement stage, malic acid accumulation of ‘SGP1’ was extremely significantly negatively correlated with MDH and PEPC activities, and significantly positively correlated with PEPCK and VHA activities, while there was a extremely significantly or significantly negative correlation between the malic acid accumulation and activities of PEPC, ME and VHP in ‘Golden Delicious’. The malic acid accumulation in ‘SGP1’ and ‘Golden Delicious’ at maturation stage was extremely significantly or significantly negatively correlated with MDH, PEPC, ME and VHP activities. It was found that ‘SGP1’ was a excellent variation strain of ‘Golden Delicious’ apple with low acid content, which was dominated by malic acid. The types and activities of enzymes that mainly regulate malic acid accumulation were different from those of ‘Golden Delicious’, resulting in the low acid quality of ‘SGP1’. This study laid a foundation for further exploring the formation mechanism of low acid in fruits and cultivating new varieties with high sugar and low acid.

Abstract:We studied the effects of foliar spraying silicon (500, 1 000, 2 000, and 4 000 mg/L) on growth and development, antioxidant enzyme activity, yield and quality in Astragalus membranaceus var. mongholicus during seedling stage, flowering stage and rhizome elongation stage by randomized trial group, and also detected the control effect of foliar spraying silicon on powdery mildew and root rot to reveal the mechanism of silicon on enhancing disease resistance, improving quality and yield of A. membranaceus var. mongholicus, and provide theoretical basis for efficient cultivation of A. membranaceus var. mongholicus in production. The results showed that: (1) the application of different concentrations of silicon could increase plant height, stem diameter, plant width and chlorophyll content, and promote the growth of A. membranaceus var. mongholicus, and better treated with 2 000 mg/L silicon concentration. (2) Spraying silicon with different concentrations could increase the activities of antioxidant enzymes such as SOD, CAT, POD and APX and reduce the content of MDA in different growth stages. It was better at 2 000 mg/L silicon concentration during flowering and rhizome elongation. (3) When the silicon concentration was 2 000 mg/L, the control effects of A. membranaceus var. mongholicus against powdery mildew and root rot reached the highest, 47.22% and 38.80% respectively. (4) Spraying silicon with different concentrations could increase the dry and fresh biomass, yield, soluble extract and astragaloside IV content of single plant of A. membranaceus var. mongholicus, When the concentration of silicon was 2 000 mg/L, the contents of soluble extract and astragaloside IV increased by 16.48% and 31.96% respectively. It was found that foliar spraying of appropriate concentration of silicon could significantly enhance the resistance to powdery mildew and root rot of A. membranaceus var. mongholicus, promote plant growth, significantly improve the yield and quality of medicinal materials, and the effect was the best when the silicon concentration was 2 000 mg/L.

Abstract:‘Bartzella’ is an excellent variety of Itoh peony ［Paeonia Itoh group］ because it can be planted in pots offseason. Growth and development, flowering quality, and related physiological indexes were evaluated following application of watersoluble fertilizer (NPK=202020+TE) (0, 0.8, 1.2 and 1.6 g·L^-1) in pots planted with ‘Bartzella’ in the south of China in winter at the initial stage of stem elongation. The results showed that: (1) fertilization significantly increased growth and nutrients of various organs of the plants. (2) Contents of chlorophyll, soluble protein and soluble sugar in leaves, stem length and diameter, bud diameter, and nitrogen and potassium levels in various organs increased with increasing dose. Bud diameter of the plants treated by 1.2 and 1.6 g·L^-1 increased by 4.4% and 7.7% compared with the control (P<0.05), cultivation time decreased by 4.45 and 2.65 d, and the best viewing period increased by 5.08 and 1.70 d, respectively. (3) Flower diameter and flower formation rate per plant increased by 16.0% and 13.5% (P<0.05), respectively, and contents of flavonoids and carotenoids and yellowness of petals increased (P<0.05). Our results show that appropriate concentration of watersoluble fertilizer can significantly coordinate development of stems, leaves and flowers of offseason cultivated ‘Bartzella’ and can be used in potted cultivation. The dose of 1.2 g·L^-1 is suggested.

Abstract:The structure and composition of rhizosphere microbial communities are affected by halophyte species and their different salt tolerance regulation modes. In order to clarify the difference of fungal community structure and composition between rhizosphere and bulk soils of different halophytes and their relationship with soil environment, we collected rhizosphere and bulk soil of Phragmites communis, Suaeda salsa, and Aeluropus sinensis from the 0-20 cm soil layer of three halophytes in the Yellow River Delta. The diversity and structure of the fungal community were analyzed by highthroughput sequencing, and the relationship between the fungal community characteristics and soil physical and chemical factors was explored. The results showed that: (1) the fungal richness is higher in rhizosphere than in bulk soil for all three halophyte species and the highest fungal richness was found in rhizosphere soil of Aeluropus sinensis. (2) The distance heat map showed that the similarity between P. communis and S. salsa bulk soil fungal communities was the greatest. (3) Soil fungal diversity and richness were positively correlated with soil total carbon, total nitrogen, available phosphorus and pH, but negatively correlated with soil salt content. (4) In rhizosphere and bulk soils of three halophytes, Glomeromycota was the absolute dominant phylum, while Scutellospora was the dominant genus. (5) RDA analysis showed that soil salt content was an important factor affecting soil fungal community structure, and the abundance of Glomeromycota was positively correlated with soil total nitrogen, total carbon, available phosphorus, organic carbon and pH, while negatively correlated with soil salt. (6) The characteristics of plant soil fungal community varied with the type of halophytes and the distance from the soil samples to the roots of host plants.

Abstract:To better construct walnut core germplasm, this paper uses 245 walnut germplasm resources as test materials and uses the genetic variation data of quantitative traits to explore its construction methods. We used random sampling strategy, deviation degree sampling strategy, and site priority sampling strategy, combined with 8 gradients (5%, 10%, 15%, 20%, 25%, 30%, 40% and 50%). The sampling ratio of the core collection was constructed by clustering multiple times. The core collection was compared with the original collection and the reserved collection by ttest. The core collection was evaluated, and the core collection was confirmed by principal component analysis and phenotypic traits. The results showed that: (1) the deviation degree sampling strategy was selected, the overall sampling ratio was 50%, and 131 core germplasm resources of walnut group Guizhou walnut plants were constructed. (2) The principal component analysis of 13 quantitative traits in the core pool of germplasm resources was carried out, and the cumulative contribution rate reached more than 76.48%. The distribution of walnut core germplasm and original germplasm in the principal component diagram was similar. In this way, the genetic structure of the original walnut germplasm is effectively preserved, and the redundancy of the germplasm is effectively avoided. (3) Under the clustering conditions of Euclidean distance combined with the intergroup connection method, the deviation degree sampling strategy is the best method to construct walnut core collection.

Abstract:In order to explore the influencing factors of the establishment of regeneration system of Gymnocarpos przewalskii and determine the origin of adventitious shoots, with the stem segments of the superior individual of G. przewalskii as explants, we used different concentrations of 6  BA and IBA to screen the optimal concentration combinations for callus proliferation and adventitious shoot regeneration in this study. The key influencing factors for rooting induction were determined, and the regeneration system was established. The differentiation process of adventitious shoots was analyzed to confirm its origin. The results showed that : (1) the optimal medium for callus proliferation was MS+1 mg·L^-1 IBA+1 mg·L^-1 6BA+30 g·L^-1 sucrose+7 g·L^-1 agar. Intersubjectivity analysis showed that IBA was the key influencing factor. The callus size increased first and then decreased with the change of IBA concentration. (2) The best adventitious shoot induction medium was MS+0.5 mg·L^-1 6BA+30 g·L^-1 sucrose+7 g·L^-1 agar, the number of adventitious shoots was 4.9 per piece, and the germination rate was 92.3%. (3) For rooting induction, SH basic medium and sucrose concentration were the key factors. The optimal rooting medium was SH+0-10 g·L^-1 sucrose+7 g·L^-1 agar, and the rooting rate was 91.3%. (4) Adventitious shoots originated from meristem cells on the surface of callus, which were exogenous. In this study, the regeneration system of G. przewalskii was established through organogenesis, and the adventitious shoots were identified as the external origin, which laid a foundation for the protection and sustainable utilization of G. przewalskii, a rare and endangered forest germplasm resource, and provided an effective way for its future development and utilization.

Abstract:Silene holosteifolia Bocquet et Chater, a newly recorded species of Caryophyllaceae from China, is reported; based on the collections housed at herbaria, a detailed description and line drawing are first provided herein. S. holosteifolia was previously found in Nepal and Bhutan, and now first discovered in Gyirong and Nyalam of Shigatse, Tibet, China. It is most similar to S. multifurcata C. L. Tang, but differs from the latter by its flower usually solitary, rarely 2-3 flowered cymes, ovatelanceolate bracts, campanulate or globose calyx with black longitudinal veins disjoint at apex, yellowish green petals, limbs repeatedly branched result in fringed, lobes linear, and styles 3. Voucher specimens are deposited in PE, KUN and US.

Abstract:Meehania hongliniana B.Y. Ding & X.F. Jin is reported as a newly recorded species of Lamiaceae from Chongqing. The detailed morphological description and photos were provided, and vouncher specimen was preserved in Herbarium of Chongqing Museum of Natural History (CQNM). The species was firstly found in Nanhua Mountain, Zhejiang Province. It has sterile stems and fertile stems, which are different from other species in this genus.

Abstract:Plants have evolved large families of receptorlike kinases(RLK) to perceive and process external signal to form coordinated responses, which are critical to adapt to various physiological processes and biological metabolism of plants. M/MLDRLKs are unique to plants because of their unique and novel malectinlike domains in their extracellular domain. Recent studies have shown that M/MLDRLKs involved in plant development and biotic/abiotic stress regulation. This article reviews the research history, structural characteristics and biological functions of plant M/MLDRLKs. We systematically reviewed the recent studies on the functions of M/MLDRLKs in regulating plant roots, leaves, flower development and various stress responses. This will provide a reference for elucidating the physiological functions of M/MLDRLKs in the process of plant growth and development.