High-nitrogen fertilizer alleviated adverse effects of drought stress on the growth and photosynthetic characteristics of Hosta 'Guacamole'.

BACKGROUND: Several plants are facing drought stress due to climate change in recent years. In this study, we aimed to explore the effect of varying watering frequency on the growth and photosynthetic characteristics of Hosta 'Guacamole'. Moreover, we investigated the effect of high-nitrogen and -potassium fertilizers on alleviating the impacts of drought stress on the morphology, photosynthetic characteristics, chlorophyll fluorescence, fast chlorophyll a fluorescence transient, JIP-test parameters, and enzymatic and non-enzymatic scavenging system for reactive oxygen species (ROS) in this species. RESULTS: Leaf senescence, decreased chlorophyll contents, limited leaf area, and reduced photosynthetic characteristics and oxygen-evolving complex (OEC) activity were observed in Hosta 'Guacamole' under drought stress. However, high-nitrogen fertilizer (30-10-10) could efficiently alleviate and prevent the adverse effects of drought stress. High-nitrogen fertilizer significantly increased chlorophyll contents, which was higher by 106% than drought stress. Additionally, high-nitrogen fertilizer significantly improved net photosynthetic rate and water use efficiency, which were higher by 467% and 2900% than those under drought stress. It attributes that high-nitrogen fertilizer could reduce transpiration rate of leaf cells and stomatal opening size in drought stress. On the other hand, high-nitrogen fertilizer enhanced actual photochemical efficiency of PS II and photochemical quenching coefficient, and actual photochemical efficiency of PS II significantly higher by 177% than that under drought stress. Furthermore, high-nitrogen fertilizer significantly activated OEC and ascorbate peroxidase activities, and enhanced the performance of photosystem II and photosynthetic capacity compared with high-potassium fertilizers (15-10-30). CONCLUSIONS: High-nitrogen fertilizer (30-10-10) could efficiently alleviate the adverse effects of drought stress in Hosta 'Guacamole' via enhancing OEC activity and photosynthetic performance and stimulating enzymatic ROS scavenging system.

SWATH-MS-Based Proteomics Reveals the Regulatory Metabolism of Amaryllidaceae Alkaloids in Three Lycoris Species.

Alkaloids are a class of nitrogen-containing alkaline organic compounds found in nature, with significant biological activity, and are also important active ingredients in Chinese herbal medicine. Amaryllidaceae plants are rich in alkaloids, among which galanthamine, lycorine, and lycoramine are representative. Since the difficulty and high cost of synthesizing alkaloids have been the major obstacles in industrial production, particularly the molecular mechanism underlying alkaloid biosynthesis is largely unknown. Here, we determined the alkaloid content in Lycoris longituba, Lycoris incarnata, and Lycoris sprengeri, and performed a SWATH-MS (sequential window acquisition of all theoretical mass spectra)-based quantitative approach to detect proteome changes in the three Lycoris. A total of 2193 proteins were quantified, of which 720 proteins showed a difference in abundance between Ll and Ls, and 463 proteins showed a difference in abundance between Li and Ls. KEGG enrichment analysis revealed that differentially expressed proteins are distributed in specific biological processes including amino acid metabolism, starch, and sucrose metabolism, implicating a supportive role for Amaryllidaceae alkaloids metabolism in Lycoris. Furthermore, several key genes collectively known as OMT and NMT were identified, which are probably responsible for galanthamine biosynthesis. Interestingly, RNA processing-related proteins were also abundantly detected in alkaloid-rich Ll, suggesting that posttranscriptional regulation such as alternative splicing may contribute to the biosynthesis of Amaryllidaceae alkaloids. Taken together, our SWATH-MS-based proteomic investigation may reveal the differences in alkaloid contents at the protein levels, providing a comprehensive proteome reference for the regulatory metabolism of Amaryllidaceae alkaloids.

Development of EST-SSR markers based on transcriptome sequencing for germplasm evaluation of 65 lilies (Lilium).

BACKGROUND: Lilium genus consists of approximately 100 species and numerous varieties, many of which are interspecific hybrids, which result in a complicated genetic background. The germplasm identification, genetic relationship analysis, and breeding of Lilium rely on exploiting genetic information among different accessions. Hence, an attempt was made to develop new EST-SSR markers and study the molecular divergence among 65 genotypes of Lilium. METHODS AND RESULTS: A total of 5509 EST-SSRs were identified from the high-throughput sequencing database of L. 'Elodie'. After primer screening, six primer pairs with the most abundant polymorphic bands were selected from 100 primer pairs. Combined with the other 10 reported SSR primers, a total of 16 pairs detected genetic information with an average PIC value of 0.7583. The number of alleles per locus varied from four to 33, the expected heterozygosity varied from 0.3289 to 0.9231, and the observed heterozygosity varied from 0.2857 to 0.5122. Based on the phylogenic results, 22 Asiatic hybrids (A), seven Longiflorum × Asiatic hybrids (LA), as well as two native species were grouped. Eighteen Oriental hybrids (O) and nine Oriental × Trumpet (OT) hybrids, four native species, one LO, and one LL (L. pardalinum × L. longiflorum) variety were grouped. CONCLUSIONS: Two major clusters were reported and a large number of genotypes were grouped based on UPGMA and STRUCTURE analysis methods. The PIC value as well as other parameters revealed that the EST-SSR markers selected were informative. In addition, the clustering pattern displayed better agreement with the cultivar's pedigree. The newly identified SSRs in this study provides molecular markers for germplasm characterization and genetic diversity for Lilium.

Comparative Metabolomics Analysis of Stigmas and Petals in Chinese Saffron (Crocus sativus) by Widely Targeted Metabolomics.

The dried stigmas of Crocus sativus, commonly known as saffron, are consumed largely worldwide because it is highly valuable in foods and has biological activities beneficial for health. Saffron has important economic and medicinal value, and thus, its planting area and global production are increasing. Petals, which are a by-product of the stigmas, have not been fully utilized at present. We compared the metabolites between the stigmas and petals of C. sativus using a non-targeted metabolomics method. In total, over 800 metabolites were detected and categorized into 35 classes, including alkaloids, flavonoids, amino acids and derivatives, phenols and phenol esters, phenylpropanoids, fatty acyls, steroids and steroid derivatives, vitamins, and other metabolites. The metabolite composition in the petals and stigmas was basically similar. The results of the study showed that the petals contained flavonoids, alkaloids, coumarins, and other medicinal components, as well as amino acids, carbohydrates, vitamins, and other nutritional components. A principal components analysis (PCA) and an orthogonal partial least-squares discriminant analysis (OPLS-DA) were performed to screen the different metabolic components. A total of 339 differential metabolites were identified, with 55 metabolites up-regulated and 284 down-regulated. The up-regulated metabolites, including rutin, delphinidin-3-O-glucoside, isoquercitrin, syringaresinol-di-O-glucoside, dihydrorobinetin, quercetin, and gallocatechin, were detected in the petals. The down-regulated metabolites were mainly glucofrangulin B, acetovanillone, daidzein, guaiazulene, hypaphorine, indolin-2-one, and pseudouridine. KEGG annotation and enrichment analyses of the differential metabolites revealed that flavonoid biosynthesis, amino acids biosynthesis, and arginine and proline metabolism were the main differentially regulated pathways. In conclusion, the petals of C. sativus are valuable for medicine and foods and have potential utility in multiple areas such as the natural spice, cosmetic, health drink, and natural health product industries.

Phylogenetic analysis and character evolution of tribe Arethuseae (Orchidaceae) reveal a new genus Mengzia.

Delimitation of the tribe Arethuseae has varied considerably since it was first defined. The relationships within Arethuseae, particularly within the subtribe Arethusinae, remain poorly elucidated. In this study, we reconstructed the phylogeny of Arethuseae, using six plastid markers (matK, ycf1, rbcL rpoc1, rpl32-trnL and trnL-F) from 83 taxa. The ancestral state reconstruction of 11 selected morphological characters was also conducted to identify synapomorphies and assess potential evolutionary transitions. Morphological character comparision between the distinct species Bletilla foliosa and other species are conducted. Our results unequivocally supported the monophyly of Arethuseae, which included highly supported clades and a clear synapomorphy of non-trichome-like lamellae. Furthermore, B. foliosa formed a separate clade in the subtribe Arethusinae, instead of clustering with the other Bletilla species in the subtribe Coelogyninae. The morphological characters comparision further showed that the B. foliosa clade could be distinguished from other genera in Arethuseae by multiple characters, including presence of lateral inflorescence, three lamellae with trichome-like apex and four pollinia. In light of these molecular and morphological evidences, we propose Mengzia as a new genus to accommodate B. foliosa and accordingly provide descriptions of this new genus and combination.

Transcriptomic and Metabolomic Analyses Reveals That Exogenous Methyl Jasmonate Regulates Galanthamine Biosynthesis in Lycoris longituba Seedlings.

The Amaryllidaceae alkaloid galanthamine (Gal) in Lycoris longituba is a secondary metabolite that has been used to treat Alzheimer's disease. Plant secondary metabolism is affected by methyl jasmonate (MeJA) exposure, although the regulatory mechanisms of MeJA on L. longituba seedlings remains largely unknown. In the present study, 75, 150, and 300 µM MeJA were used as treatments on L. longituba seedlings for 7, 14, 21, and 28 days, while 0 µM MeJA was used as the control (MJ-0). The effect of exogenous MeJA on Gal synthesis in L. longituba was then investigated using transcriptomic sequencing and metabolite profiling via GC-MS and LC-MS analysis. Galanthamine (Gal), lycorine (Lyc), and lycoramine (Lycm) abundances were 2. 71-, 2. 01-, and 2.85-fold higher in 75 µM MeJA (MJ-75) treatment plants compared to MJ-0 treatment plants after 7 days of cultivation. Transcriptomic analysis further showed that MJ-75 treatment significantly induced the expression of norbelladine synthase (NBS) and norbelladine 4'-O-methyltransferase (OMT), which are involved in the Gal biosynthesis pathway. In addition, increased expression was observed in MJ-75 treatment plants for genes in the JA synthesis and JA signaling pathways including those of allene oxide cyclase (AOC), 12-oxo-phytodienoic acid reductase (OPR), jasmonic acid amino acid synthase (JAR), and transcription factor MYC. The L. longituba tyrosine decarboxylase (LlTYDC) enzyme was identified and proposed to be involved in the Gal biosynthetic pathway. Metabolomics results demonstrated that the accumulation of Amaryllidaceae alkaloids, and especially alkaloids in the Gal biosynthesis pathway, could be induced by MJ-75 treatment. Interestingly, metabolites in the JA synthesis pathway were also affected by MeJA treatment. Overall, this multi-omics study suggests that both the JA synthesis/JA signaling and Gal biosynthesis pathways were affected by exogenous MeJA treatment. This comprehensive study of gene expression and metabolite contents can help us better understand the molecular mechanisms underlying MeJA-mediated Gal biosynthesis in L. longituba.

Decline of three farmland pest species in rapidly urbanizing landscapes.

Urbanization is a pressing challenge for earth's humans because it is changing not only natural environments but also agricultural lands. Yet, the consequences of cropland loss on pest insect populations that largely depend on these habitats remain largely unclear. We used a 17-year data set to investigate the dynamics of three moth pest species (i.e., striped stem borer, yellow stem borer, and pink stem borer) and their driving forces across the largest mega-urban region of China. Total abundance of three pest species is declined by about 80%, which was strongly associated with cropland loss during rapid urbanization. Our findings indicate that not only the increasing conversion of natural areas to human-dominated landscapes but also that of agricultural lands to urban landscapes can be critical to insect populations. It is therefore essential to monitor and understand the insect dynamics in rapidly urbanizing regions, which are currently found in many developing countries worldwide.

The circadian-controlled PIF8-BBX28 module regulates petal senescence in rose flowers by governing mitochondrial ROS homeostasis at night.

Reactive oxygen species (ROS) are unstable reactive molecules that are toxic to cells. Regulation of ROS homeostasis is crucial to protect cells from dysfunction, senescence, and death. In plant leaves, ROS are mainly generated from chloroplasts and are tightly temporally restricted by the circadian clock. However, little is known about how ROS homeostasis is regulated in nonphotosynthetic organs, such as petals. Here, we showed that hydrogen peroxide (H2O2) levels exhibit typical circadian rhythmicity in rose (Rosa hybrida) petals, consistent with the measured respiratory rate. RNA-seq and functional screening identified a B-box gene, RhBBX28, whose expression was associated with H2O2 rhythms. Silencing RhBBX28 accelerated flower senescence and promoted H2O2 accumulation at night in petals, while overexpression of RhBBX28 had the opposite effects. RhBBX28 influenced the expression of various genes related to respiratory metabolism, including the TCA cycle and glycolysis, and directly repressed the expression of SUCCINATE DEHYDROGENASE 1, which plays a central role in mitochondrial ROS (mtROS) homeostasis. We also found that PHYTOCHROME-INTERACTING FACTOR8 (RhPIF8) could activate RhBBX28 expression to control H2O2 levels in petals and thus flower senescence. Our results indicate that the circadian-controlled RhPIF8-RhBBX28 module is a critical player that controls flower senescence by governing mtROS homeostasis in rose.

AUXIN RESPONSE FACTOR 18-HISTONE DEACETYLASE 6 module regulates floral organ identity in rose (Rosa hybrida).

The phytohormone auxin plays a pivotal role in floral meristem initiation and gynoecium development, but whether and how auxin controls floral organ identity remain largely unknown. Here, we found that auxin levels influence organ specification, and changes in auxin levels influence homeotic transformation between petals and stamens in rose (Rosa hybrida). The PIN-FORMED-LIKES (PILS) gene RhPILS1 governs auxin levels in floral buds during floral organogenesis. RhAUXIN RESPONSE FACTOR 18 (RhARF18), whose expression decreases with increasing auxin content, encodes a transcriptional repressor of the C-class gene RhAGAMOUS (RhAG), and controls stamen-petal organ specification in an auxin-dependent manner. Moreover, RhARF18 physically interacts with the histone deacetylase (HDA) RhHDA6. Silencing of RhHDA6 increases H3K9/K14 acetylation levels at the site adjacent to the RhARF18-binding site in the RhAG promoter and reduces petal number, indicating that RhARF18 might recruit RhHDA6 to the RhAG promoter to reinforce the repression of RhAG transcription. We propose a model for how auxin homeostasis controls floral organ identity via regulating transcription of RhAG.

Transcriptome Analysis of Different Tissues Reveals Key Genes Associated With Galanthamine Biosynthesis in Lycoris longituba.

L ycoris longituba is a traditional medicinal plant containing the bioactive compound galanthamine (Gal), a type of Amaryllidaceae alkaloid and can be used to treat Alzheimer's disease. However, research on its genome or transcriptome and associated genes in the biosynthetic pathway is incomplete. In this study, we estimated the nuclear genome size of this species to be 29.33 Gb by flow cytometry. Then, RNA sequencing of the leaves, roots, and bulbs of L. longituba was carried out. After de novo assembly, 474,589 all-transcripts and 333,440 all-unigenes were finally generated. In addition, the differentially expressed genes (DEGs) were identified, and genes involved in the galanthamine metabolic pathway encoding tyrosine decarboxylase (TYDC), phenylalanine ammonia-lyase (PAL), cinnamate 4-hydroxylase (C4H), p-coumarate 3-hydroxylase (C3H), norbelladine synthase (NBS), norbelladine 4'-O-methyltransferase (OMT), and noroxomaritidine synthase (CYP96T1) were detected and validated by real-time quantitative PCR analysis. One candidate gene, Lycoris longituba O-Methyltransferase (LlOMT), was identified in the proposed galanthamine biosynthetic pathway. Sequence analysis showed that LlOMT is a class I OMT. LlOMT is localized in the cytoplasm, and biochemical analysis indicated that the recombinant LlOMT catalyzes norbelladine to generate 4'-O-methylnorbelladine. The protoplast transformation result showed that the overexpression of LlOMT could increase the Gal content. Our results indicate that LlOMT may play a role in galanthamine biosynthesis in L. longituba. This work provides a useful resource for the metabolic engineering of Amaryllidaceae alkaloids.

Global synthesis of effects of plant species diversity on trophic groups and interactions.

Numerous studies have demonstrated that plant species diversity enhances ecosystem functioning in terrestrial ecosystems, including diversity effects on insects (herbivores, predators and parasitoids) and plants. However, the effects of increased plant diversity across trophic levels in different ecosystems and biomes have not yet been explored on a global scale. Through a global meta-analysis of 2,914 observations from 351 studies, we found that increased plant species richness reduced herbivore abundance and damage but increased predator and parasitoid abundance, predation, parasitism and overall plant performance. Moreover, increased predator/parasitoid performance was correlated with reduced herbivore abundance and enhanced plant performance. We conclude that increasing plant species diversity promotes beneficial trophic interactions between insects and plants, ultimately contributing to increased ecosystem services.

Characterization of morphology and physicochemical properties of native starches isolated from 12 Lycoris species.

In this study, starch was isolated from 13 genotypes of 12 Lycoris species, and the morphology, granule size distribution and physicochemical properties, including apparent amylose content (AAC), Rapid Visco Analyzer (RVA) pasting properties, textural properties, thermal and retrogradation properties were characterized. The majority of starch granules of the 13 Lycoris genotypes were oval in shape, and granule size followed a normal distribution with a mean diameter of 20-30 µm. Contrary to previously published findings, the XRD results revealed that lycoris starches had either C-type or CA-type crystallinity. All lycoris starches showed high AAC varying from 25.6% to 32.7%, and low gelatinization temperature (GT) ranging from 58.8 to 69.7℃. Inter-relationships among 18 starch quality traits were analyzed based on correlation analysis. The present study provides information on lycoris starch characteristics which should serve as a useful guide for later studies on lycoris starch utilization in food and non-food industries.

Effect of Exogenous Gibberellin, Paclobutrazol, Abscisic Acid, and Ethrel Application on Bulblet Development in Lycoris radiata.

Lycoris species have great ornamental and medicinal values; however, their low regeneration efficiency significantly restricts their commercial production. Exogenous hormone application is an effective way to promote bulblet development, but their effect on Lycoris radiata has not been verified to date. In the present study, we examined the effect of different exogenous hormones on bulblet development in L. radiata, and found that gibberellic acid (GA) significantly inhibited, whereas paclobutrazol (PBZ), abscisic acid (ABA), and ethrel promoted bulblet development, especially PBZ, a GA biosynthesis inhibitor. Furthermore, GA reduced endogenous cytokinin (CK) content, as well as the activities of carbohydrate metabolism enzymes, including sucrose synthase (SUS) and glucose-1-phosphate adenylyltransferase (AGPase), by downregulating the expression levels of LrSUS1, LrSUS2, and genes encoding AGPase large and small subunits. This resulted in the decrease in carbohydrate accumulation in the bulblets, thus hindering their development. PBZ had the opposite effect to GA on carbohydrate metabolism; it decreased endogenous GA15 and GA24, thereby promoting bulblet development. ABA promoted endogenous auxin content and the activities of starch synthesis enzymes, especially soluble starch synthase (SSS) and granule-bound SS (GBSS), through the up-regulation of the expression levels of LrSS1, LrSS2, and LrGBSS1 genes, which could also result in the accumulation of carbohydrates in the bulblets and promote their development. In addition, ethrel application partly promoted bulblet development by promoting endogenous CK content. Although the accumulation of carbohydrates and the activity of starch enzymes were increased by ethrel treatment, we hypothesized that the effect of ethrel on regulating carbohydrate metabolism may be indirect. Our results could provide a basis for improving the propagation efficiency of L. radiata for production, as well as propose some directions for future research.

Increasing plant diversity with border crops reduces insecticide use and increases crop yield in urban agriculture.

Urban agriculture is making an increasing contribution to food security in large cities around the world. The potential contribution of biodiversity to ecological intensification in urban agricultural systems has not been investigated. We present monitoring data collected from rice fields in 34 community farms in mega-urban Shanghai, China, from 2001 to 2015, and show that the presence of a border crop of soybeans and neighboring crops (maize, eggplant and Chinese cabbage), both without weed control, increased invertebrate predator abundance, decreased the abundance of pests and dependence on insecticides, and increased grain yield and economic profits. Two 2 year randomized experiments with the low and high diversity practices in the same locations confirmed these results. Our study shows that diversifying farming practices can make an important contribution to ecological intensification and the sustainable use of associated ecosystem services in an urban ecosystem.

Rapid visual detection of lily mottle virus using a loop-mediated isothermal amplification method.

Lily mottle virus (LMoV; genus Potyvirus, family Potyviridae) infects plants of the genus Lilium, causing a reduction in flower and bulb quality. A rapid and sensitive loop-mediated isothermal amplification (LAMP) assay was developed to detect the coat protein gene of LMoV. This LAMP method was highly specific for LMoV, with no cross-reaction with other lily viruses. The sensitivity of LMoV using the LAMP assay was 100 times more sensitive than that using conventional polymerase chain reaction. A reverse transcription LAMP (RT-LAMP) was then successfully applied to detect LMoV RNA. The newly established LAMP and one-step RT-LAMP provide an alternative method for detecting LMoV in lily plants.

Identification and expression analysis of EST-based genes in the bud of Lycoris longituba.

To obtain a primary overview of gene diversity and expression pattern in Lycoris longituba, 4,992 ESTs (Expressed Sequence Tags) from L. longituba bud were sequenced and 4,687 cleaned ESTs were used for gene expression analysis. Clustered by the PHRAP program, 967 contigs and 1,343 singlets were obtained. Blast search showed that 179 contigs and 227 singlets (totally 1,066 ESTs) had homologues in GenBank and 3,621 ESTs were novel.

[Sequence of the ITS region of nuclear ribosomal DNA(nrDNA) in Xinjiang wild Dianthus and its phylogenetic relationship].

Xinjiang is a center of distribution and differentiation of genus Dianthus in China, and has a great deal of species resources. The sequences of ITS region (including ITS-1, 5.8S rDNA and ITS-2) of nuclear ribosomal DNA from 8 species of genus Dianthus wildly distributed in Xinjiang were determined by direct sequencing of PCR products. The result showed that the size of the ITS of Dianthus is from 617 to 621 bp, and the length variation is only 4 bp. There are very high homogeneous (97.6%-99.8%) sequences between species, and about 80% homogeneous sequences between genus Dianthus and outgroup. The sequences of ITS in genus Dianthus are relatively conservative. In general, there are more conversion than transition in the variation sites among genus Dianthus. The conversion rates are relatively high, and the ratios of conversion/transition are 1.0-3.0. On the basis of phylogenetic analysis of nucleotide sequences the species of Dianthus in China would be divided into three sections. There is a distant relationship between sect. Barbulatum Williams and sect. Dianthus and between sect. Barbulatum Williams and sect. Fimbriatum Williams, and there is a close relationship between sect. Dianthus and sect. Fimbriatum Williams. From the phylogenetic tree of ITS it was found that the origin of sect. Dianthusis is earlier than that of sect. Fimbriatum Williams and sect. Barbulatum Williams.

[Analysis of the inter-species relationships on lycoris Amaryllidaceae) by use of RAPD].

The fingerprints of 13 species in genus Lycoris were generated by use of RAPD method. Forty-one primers were screened from 520 random primers, and a total of 350 DNA fragments were amplified ranging from 0.3-3.0 kb, 253 (72.3%) of which were polymorphic. The average number of DNA band produced by each primer was 6.2. Nei's similarity coefficients and genetic distances were calculated by use of the software of TFPGA version 1.3 and dendrogram of Lycoris was constructed using UPGMA. It is indicated that the 13 species of the genus Lycoris were divided into two groups, and five species of the genus including L. rosea, L. haywardii, L. straminea, L. sprengeri and L. radiata with monotype karyotypes (I-shaped) were clustered together respectively. The basic chromosome number was x = 11. The others which have two-types karyotypes (I-shaped and V-shaped) were clustered together respectively. They were L. houdyshelii, L. albiflora, L. chinensis, L. longituba, L. anhuiensis, L. squmigera, L. caldwellii and L. aurea. The closest relationship was between L. rosea and L. haywardii. L. radiata is highly divergent from L. aurea. The results were in consistence with that of the analysis of chromosome karyotype. The present paper discussed the problems whether L. rosea, L. haywardii and L. stramina originated as natural hybrids and taxonomy position of L. albiflora, L. straminea and L. houdyshelii based on the RAPD analysis.

Cloning and Expression of Actin Gene of Schistosoma japonicum Chinese Strain.

A 1 131 bp cDNA fragment was amplified by RT-PCR from adult Schistosoma japonicum(Chinese strain) mRNA with primers designed according to published SmAct2 encoding Schistosoma mansoni actin. Sequence analysis indicated that this fragment, with 92% homology to SmAct2, was a complete open reading fragment (ORF) of actin gene of Schistosoma japonicum (Chinese strain). This gene was cloned into the expression vector pET28a( ) and subsequently expressed in Escerichia coli. SDS-PAGE revealed that the molecular weight of this expressed product was 47 kD. Western blotting showed that the recombinant protein had good reactivity with the rabbit serum immunized with Sj worm antigen, indicating that this gene encode actin of Schistosoma japonicum(Chinese strain).