The technology of planting Sesuvium portulacastrum for ecological restoration has been widely used in Fujian and other places with remarkable results. It is worth discussing whether it can be applied in Hangzhou Bay with eutrophication. The rapid growth of S. portulacastrum can absorb large amounts of nitrogen and phosphorus and remove excess nutrients from water. In this paper, the ecological adaptability of S. portulacastrum to different light intensity, salinity and temperature were studied, and the low temperature and high salinity stress and compound stress were studied further, which is to meet the actual restoration necessary of Hangzhou Bay wetland or water area using S. portulacastrum. S. portulacastrum had a wide tolerance to light intensity, with a light saturation point of 300 μmol/(m²·s), and was intolerant to high light irradiation, but the inhibition of high light on relative electron transfer efficiency was low. S. portulacastrum had a wide range of tolerance to salinity, which could grow in low salinity or fresh water, and the species can tolerate high salt stress more than 25. It grew better in salinity 15 than those of all treatment groups (P<0.05). Appropriate salt treatment could promote root growth and development. S. portulacastrum could tolerate a wide range of temperature expect for very low temperature. S. portulacastrum still maintained a high growth rate in high temperature, 25 ℃ was the best status for the species growth, and the growth rate was significantly higher than that of other treatment group (P<0.05) with accumulation of dry matter faster, plant height, root length grew rapidly and leaf number increased. Low temperature stress in 5 ℃ was reversible and the plant could grow when temperature roise. But the plant was completely dead under 0 ℃ in about 24 days. The plants in the fresh water group died at 5 ℃, but the survival rate of salinity 15 was 100% at 25 ℃, the survival rate of salinity 25 was 40% at 0 ℃, and all plants in the fresh water group died, indicating that salt stress may be beneficial to plant resistance to low temperature stress. Outdoor experiments showed that S. portulacastrum could adapt to Hangzhou Bay climate, but the effect of extreme weather needs to be considered. In conclusion, the ecological restoration technology of S. portulacastrum could be applied in Hangzhou Bay basically, and the study would provide a new idea for the ecological restoration of Hangzhou Bay.

Cassava is an important cash crop in Southern China, which is enriched with starch in the tuber roots. The analysis of the regulation mechanism of starch synthesis in cassava root would contribute to the improvement of yield and high starch molecular in cassava. AGPase is composed of large subunit and small subunit, and it catalyzes G-1-P and ATP to form ADPG and PPi, in which ADPG is the substrate of starch biosynthesis. Therefore, AGPase is a rate-limiting enzyme in plant starch synthesis, and improving the activity of AGPase is beneficial for the accumulation of crop starch and the improvement of yield. The small subunit encoded by MeAGPS1a is the catalytic center of AGPase in cassava. Previous studies have shown that the growth response factor MeSAUR1 as a transcription factor positively regulates the expression of MeAGPS1a gene, and yeast two-hybrid screening of a cassava cDNA library revealed that the calmodulin-like (CML) member MeCML24 is a candidate interacting protein of MeSAUR1. To determine the interaction between MeCML24 and MeSAUR1, and MeCML24 was cloned from the genome of SC8 cassava variety in this study. The length of CDS region of MeCML24 was 492 bp, encoding 163 amino acids. The physicochemical properties and secondary structure analysis of MeCML24 showed that the value of theoretical pI was 4.38, which belonging to hydrophilic protein with α-helix accounting for 52.76%, random coil accounting for 30.06%, and beta turn accounting for 11.04%. Yeast two-hybrid vector BD-MeCML24 was constructed, and the self-activation experiment showed that MeCML24 had no self-activation. Yeast two-hybrid point-to-point experiment revealed that yeast strains co-transfected with AD-MeSAUR1 and BD-MeCML24 plasmids turned blue on nutrient medium with SD/TLHA+x-α-gal, indicating that MeCML24 interacted with MeSAUR1. The fusion protein MeSAUR1-nEYFP and MeCML24-cEYFP were co-expressed in tobacco leaves by bimolecular fluorescence complementation (BiFC) experiment, and the fluorescence signal of yellow fluorescent protein EYFP was detected under laser confocal microscope, which further proved the interaction between MeCML24 and MeSAUR1. Finally, the interaction between MeCML24 and MeSAUR1 negatively regulated the expression of MeAGPS1a by double luciferase experiment. The study revealed the mechanism of MeSAUR1 and MeCML24 synergistically regulating MeAGPS1a gene expression in cassava, and found that the calmodulin-like protein MeCML24 regulating the expression of MeAGPS1a, a key gene for starch synthesis in cassava root. This study would provide a theoretical basis for cultivating excellent cassava varieties by molecular biology technology.

Cassava is an important food crop in tropical regions. Cassava bacterial blight caused by Xanthomonas phoseoli pv. manihotis (Xpm) is an important disease of cassava. Excavating and identifying the genes of cassava resistance to Xpm and analyzing its disease resistance mechanism are beneficial to the development of cassava disease-resistant germplasm. Plant heat shock transcription factors (Hsfs) play an important role in the process of plants resisting biotic and abiotic stresses. In this study, the full-length heat shock protein transcription factor gene MeHsfB3a was cloned from cassava cultivar 'Huanan 8' ('SC8') by RT-PCR technology. Bioinformatics analysis found that MeHsfB3a contained two exons and one intron, with a full length of 729 bp, encoding 242 amino acids with 27.9 kDa and pI=7.59. The theoretical instability coefficient was 56.86, which is an unstable protein, and the average hydrophilicity index was-0.880, indicating that the protein has good water solubility, and the fat solubility index was 65.98. The protein was predicted to localize in the nucleus. qRT-PCR analysis found that MeHsfB3a was expressed in young leaves, mature leaves, terminal buds, petioles, tuberous roots and fibrous roots, with the highest expression in mature leaves and less in other organs. The expression of MeHsfB3a was analyzed after 0 h, 3 h, 6 h, 1 d, 3 d and 6 d after infection of cassava 'SC8' leaves by pathogen XpmHN11, and it was found that the expression of this gene was significantly increased after 1 d. This indicated that MeHsfB3a was involved in the response of 'SC8' cassava to XpmHN11. The MeHsfB3a gene of cassava 'SC8' was silenced by the VIGS technology, and the gene silencing efficiency reached 68.26%-82.44%. The leaves of silent plants were inoculated with XpmHN11, and the disease incidence was analyzed on 0 d, 3 d, and 6 d of inoculation, and it was found that the area of disease spots of the silent plants was significantly higher than that of the control. This study identified the heat shock protein transcription factor gene MeHsfB3a involved in the process of cassava resistance to XpmHN11, which would help to further analyze the disease resistance mechanism of cassava to cassava bacterial blight.

Passion fruit (Passiflora edulia Sims), as an emerging tropical fruit tree, plays a very important role in tropical agriculture. However, abiotic stresses such as drought and high temperature seriously affect its normal growth and development. Relevant studies have shown that aquaporin (AQP) can improve the stress resistance of plants. In this study, Passiflora 'Tainong' was used as the material, an aquaporin gene PePIP2 was cloned using the genome data of passion fruit. The open reading frame (ORF) was 861 bp, encoding 286 amino acids. The molecular formula was C₁₄₁₇H₂₁₅₆N₃₆₀O₃₇₃S₈, the molecular weight was 30 459.37 Da, the isoelectric point was 8.84, and the subcellular localization was on the cell membrane. Analysis of the promoter region revealed that it contained cis-acting elements involved in stress response. The expression analysis showed that PePIP2 could be induced by drought, high temperature and low temperature stress. Among them, the expression level was the highest when the soil water content was 50%, treated at 45℃ for 4 h and at 0℃ for 48 h. Transiently expressed in tobacco, the expression of PePIP2 was also induced to varying degrees under drought stress at different times. The results of this study would lay the foundation for the analysis of the stress resistance mechanism and molecular breeding of the passion fruit.

Tigernut (Cyperus esculentus L.) is a perennial herb that is native to Africa and the Mediterranean coast. Due to the shortage of edible vegetable oil and biodiesel in China, tigernut has been emerging as a promising oil crop for its wide adaptability and high oil production per unit. To promote the development and utilization of this special crop, EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) genes, which encode a key enzyme targeted by herbicide glyphosate in the shikimate pathway for the synthesis of aromatic amino acids, were identified from tigernut as well as several representative monocots based on genome and transcriptome data available. Comparative analyses revealed that (a) tigernut harbors a single EPSPS gene (denoted CeEPSPS) with seven introns as observed in most plant species; (b) its complete coding sequence of 1584 bp was further isolated using RT-PCR; (c) among 514 amino acids encoded by CeEPSPS, the first 70 residues from the N-terminal were characterized as the chloroplast signal peptide, whereas the peptide from sites 77 to 508 belongs to the highly conserved EPSP_ synthase domain (under the Pfam accession number of PF00275); (d) compared with the EPSP_ synthase domain, the chloroplast signal peptide is relatively more variable; and (e) the maturation protein of CeEPSPS was predicted to possess the theoretical molecular weight (Mw) of 47.32 kDa, the isolectric point (pI) of 5.49, the grand average of hydropathicity (GRAVY) of 0.069, the aliphatic index (AI) of 93.76, and the instability index (II) of 31.73, which is similar to other reported EPSPSs and could be categorized as a type of hydrophilic, acidic, and stable proteins; (f) phylogenetic analysis using deduced EPSPS proteins supports that tigernut is a Cyperaceae plant within Poales. Further sequence alignment and genome resequencing analyses revealed that no target site resistance mutations to glyphosate were found in all 56 germplasms investigated in this study. Gene expression analysis using qRT-PCR showed that CeEPSPS was dominantly expressed in mature leaves and tubers, which were significantly higher than that in buds, young leaves, senescent leaves, and rhizomes. Additionally, a plant vector of over-expressing CeEPSPS was also constructed, which would lay a solid foundation for the following molecular breeding for glyphosate resistant in tigernut and other species.

Harvested cucumber is sensitive to low temperature, which is subjected to chilling injury during cold storage and causes heavy postharvest losses. In this study, the method of RNA sequencing combined with bioinformatics analysis was used to analyze the transcriptomic changes of harvested cucumber when subjected to a short-term of cold treatment. The chilling injury index (CII) and relative electrical conductivity (REC) gradually increased but the chlorophyll fluorescence (F_v/F_m) decreased with increasing time when stored at 5℃, indicating that the chilling injury was obviously occurred. Compared with that before treatment (0 h), treatment at 5℃ for 12 h resulted in 2679 differentially expressed genes (DEGs), of which 1194 DEGs were up-regulated and 1485 DEGs were down regulated. Compared with treatment for 0 h, treatment for 72 h resulted in 9494 DEGs, of which 4807 DEGs were up-regulated and 4687 DEGs were down regulated. The results of KEGG enrichment analysis showed that the DEGs caused by cold treatment were most significantly enriched in the pathways of plant hormone signal transduction, phenylalanine metabolism, plant pathway interaction and phenylpropanoid biosynthesis. The results of GO enrichment analysis showed that DEGs were mainly involved in regulation of transcription DNA templated, protein phosphorylation and transmembrane transport in biological process. In cellular component, most enriched DEGs were related to organelle components such as membrane and nucleus. In molecular function, the enriched DEGs were mainly involved in ATP binding, protein serine/threonine kinase activity, DNA binding and transcription factor activity. DEGs related to hormone signal were significantly expressed when cucumber fruits were cold-treated for 12 h. However, the DEGs related to plant pathogen interaction and phenylpropanoid synthesis were significantly induced following 72 h of cold treatment. The results showed that plant hormone participated in the transmission of low temperature signals, the induced pathogenesis-related gene and phenylpropanoid biosynthesis might be important mechanisms for harvested cucumbers to improve chilling tolerance and cope with chilling stress. The results would provide new insights into the molecular mechanisms of harvested cucumber adaptation and resistance to chilling stress, and identify a lot of key gene resources for breeding cold-tolerant cucumber.

In this study, 100 matreials of innovative germplasm from Yunnan octoploid Saccharum spontaneum L. 84-268 bloodline F₂ population were used as materials, and 7 main agronomic factors including plant height, stalk diameter, brix, effective stalk number, single stalk weight, cane yield and sugar yield were measured, and frequency distribution histogram analysis, coefficient of variation analysis, correlation analysis, principal component analysis and cluster analysis were done. The results showed that the data of the 7 agronomic traits presented a good normal distribution and abundant variation with the variation coefficient ranging from 9.91% to 50.76%, and the maximum variation coefficient of sugar yield was 50.76%. Correlation analysis and stepwise regression analysis showed that the cane yield was significantly and positively correlated with plant height, stalk diameter and effective stalk number, having a determination coefficient of 0.9282. The sugar yield was mainly determined by plant height, stalk diameter, brix, single stalk weight and effective stalk number, and the coefficient of determination was 0.9160. The seven agronomic traits were integrated into three main components by principal component analysis, and the cumulative contribution rate was 86.985%. The first principal component, cane yield and sugar factor, was the most important factor, which contributing rate was 47.615%. At the Euclidean distance of 6.00, the 100 innovative materials were divided into 3 categories, and the results were consistent with the principal component scoring. The 7 traits were excellent in group Ⅰ, and a total of 15 high-quality materials were screened out, which had a high principal component score. In particular, it was worth of paying high attention to YGF₂18-226-7, YGF₂18-226-14, YGF₂18-226-89, YGF₂18-226-48, YGF₂18-226-96, YGF₂18-226-21, YGF₂18-226-43 and YGF₂18-226-5. These materials can be further screened as the parents or reserved as core germplasm for breeding research.

In order to meet the demand for high-quality leguminous forage varieties in southern livestock production, comprehensive evaluation of the botanical characters of high-quality breeding resources is the premise of breeding. Dendrolobium triangulare is a perennial shrub with large leaves, high yield and high nutritional value. It is an excellent high-protein green feed. At present, there are only studies on the genetic diversity among the subgroups of the locust, and the analysis and research on the morphological genetic diversity of the genus Desmodium Desv. are relatively scarce, and there is a lack of research on the morphological genetic diversity of germplasm in a large range. In this experiment, a random block design was adopted, and the research materials were 76 germplasm resources of the genus Desmodium Desv. 35 botanical traits were observed, and the genetic diversity characteristics of Desmodium Desv spp. were analyzed for future breeding work of Desmodium Desv. Provide basic materials. The genetic diversity was studied by morphological observational analysis. The 35 botanical traits, the hair condition on the back of the leaf (CV=46.92%), the color of the stem (CV=39.77%) and the condition of the petiole hair (CV=39.52%) had the largest coefficients of variation, indicating that the false D. triangulare. was rich in genetic diversity. There were correlations among several botanical characters, there was a very significant positive correlation between leaf length and leaf width (r=0.887), the aspect ratio was about 2.0, and the leaf shape was close to ellipse. There was a correlation between the shape of the stem and the length of the leaf (r=-0.459) and the width of the leaf (r=-0.491), indicating that if the yield of pseudo pigeon is mainly based on the leaf area, the cylindrical stem should be selected as much as possible. There was a very significant correlation between the leaf shape of the central leaflet and the length of the pod (r=0.360), so the selection of obovate leaves during breeding could improve the seed yield. There was a very significant correlation between the hair condition on the back of the leaf, the hair condition on the petiole (r=0.462) and the hair condition on the pod (r=0.589), indicating that the hair coat condition of the same plant has a high correlation, and the resources with less hair coat on the whole plant can be screened. Through cluster analysis and systematic evaluation, four germplasm resources were screened out (D. triangulare 070314022, D. triangulare GX121121004, D. triangulare 050218087, D. triangulare 050307492), and the germplasm resources had the characteristics of high yield and high quality. This experiment explored the characteristics of genetic diversity of botanical traits among the species of D. triangulare, which could provide basic materials for subsequent breeding work.

Two new records and one mainland new record of Dematiaceous hyphomycetes from China, Beltraniella fertilis Heredia, R.M. Arias, M. Reyes & R.F. Castañeda, Subulispora cylindrospora P.M. Kirk and Subulispora procurvata Tubaki wre reported. The specimens were collected from Kuankuoshui National Nature Reserve and Xishui National Nature Reserve of Guizhou. Morphological description, figures were provided for each species, ITS and LSU sequence were provided for B. fertilis and S. procurvata. The specimens are deposited in the Mycological Herbarium of Zunyi Normal College (HMZNC).

Rucheng Baimaocha (Camellia sinensis var. pubilimba Chang) is one of the four tea plants native to Hunan Province, China. Previous studies have shown that Rucheng Baimaocha is different from other three local population resources in Hunan in evolutionary status, and has distinctive characteristics in botanical characteristics, biochemical components and tea making quality. However, there are few studies on the differences of secondary metabolites of Rucheng Baimaocha germplasm resources. Using UPLC-MS/MS analysis technology, taking Anhua population (AHQT, C. sinensis var. sinensis), Chengbu Dongcha [CBDC, C. sinensis var. assamica (Masters) Kitamura], and Jianghua Kucha [JHKC, C. sinensis var. assamica (Masters) Kitamura] of typical local tea resources in Hunan as controls, the significantly different metabolites in Rucheng Baimaocha were screened and clustered by K-means analysis and differential metabolite enrichment pathway analysis. Compared with the control, 189, 180 and 162 significantly different metabolites were screened in Rucheng Baimaotea, the most species were flavonoids (69, 51 and 60 respectively), followed by phenolic acids (31, 40 and 25 respectively), and the least were lignans and coumarins (5, 4 and 4 respectively). Compared with the other three populations, Rucheng Baimaotea increased the content of 15 metabolites. The content of flavonoids and phenolic acids increased the most in Rucheng Baimaocha, and the highest increase was pinocembrin, followed by 1,2,3,6-tetra-o-galloyl-d-glucose. The differential metabolites were analyzed by K-means clustering. The metabolites with the same change trend in the four groups could be divided into nine categories. Among the four populations, there were 32 metabolites with the same change trend and the highest content in Rucheng Baimaotea, mainly flavonoids and tannins. The results of KEGG pathway enrichment of differential metabolites showed that the differential metabolites of Rucheng Baimaotea were mainly enriched in flavonoid biosynthesis pathway, flavonoid and flavonol biosynthesis pathway, phenylpropane biosynthesis pathway and so on. In addition to the differential metabolites reported in some tea, some differential metabolites less concerned in tea research were detected, such as pinocembrin, ellagic acid, kaempferol, etc. The substances would provide an important reference for the excavation and breeding of characteristic tea germplasm resources of Rucheng white tea in the later stage.