The Mimas pigcon and the Silver King pigeon are both large meat pigcon breeds with a large breeding scale in China. In order to understand the production potential and differences between the two breeds, 100 breeding eggs of Mimas and Silver King pigeons were randomly selected for artificial incubation.The egg shape index was recorded. The egg weights were recorded and then the eggs were broken to observe the development of the embryos every day during the incubation period. When the pigeons came out of their shells, they were fed by the corresponding pigeonbreeder, and the weight and appearance of the squabs were recorded during the lactation. The results showed that the egg weight, egg length and egg shape index of Mimas eggs were significantly higher than those of Silver King pigeon eggs(P<0.01).Egg weights of Mimas and Silver King pigeon eggs showed a decreasing trend from the 0th to 17th day of incubation. There was no significant difference in the growth and development process of Mimas and Silver King pigeon embryos from 0-17 d of incubation, but the yolk absorption of Silver King pigeon embryos was lower than that of Mimas embryos on the 17th day of incubation. The recorded body weights of squabs showed that the body weights of Mimas were significantly higher than that of Silver King pigeons on the 2nd and 5th day of lactation( P<0.05)， but the body weights of Silver King pigeons were significantly higher than those of Mimason at the 16th to 20th day of lactation (P<0.05).The external appearance of the squabs showed that the skin of the Silver King pigeons showed melanin deposition on the 4th day of lactation, which was significantly different from the appearance of the Mimas, and the Silver King pigeons on the 14th to 20th day of lactation had better feather development and coverage than the Mimas. In summary, the breeding and growth performance of the Mimas and Silver King pigeons have their own advantages, The Mimas having a better egg potential due to its larger egg size, while the Silver King pigeon has a faster growth rate in the later stages of lactation period, the Silver King pigeon is with higher feather attachment, which make it more suitable for meat use.In addition, the Mimas and Silver King pigeons can be crossbred according to the production needs to produce new meat pigeon breeds.This study provides basic data for the further development of the production potential of Mimas and Silver King pigeons and the breeding of new varieties.

In order to study the relationship between body weight and body measurements of 120-day-old Lion-hcad geese, a total of 501 (255 males and 246 females)geese were mcasured, and the correlation and regression analysis were carried out. The results showed that the body weight and body measurements of male geese were significantly higher than those of female geese (P<0.01).There were significantly positive correlations bctween body weight and body measurements ( P<0.01).The regression model of predicting body weight by using body measurement traits for male Lion-head geese was Y=0.471X2+0.192X6+0.187X7+0.022X9+0.042X+0.055Xμ+0.475X-10.434，where Y was body weight, X2 was chest width, X6 was pelvic width, X7 was neck circumference,X9 was half-diving length,X10 was body slant length, X11 was keel length and X12 was tibia circumference. The regression model for female geese was Y=0.384X2+0.031X4+0.297X6+0.226X7+0.094X10+0.223X12-12.227，where Y was body weight, X2 was chest width, X4 was chest Angle, X6 was pelvic width, X7 was neckcircumference, X10 was body oblique length,and X12 was tibia circumference. Our results will provide important reference for the conscrvation and breeding of Lion-head geese.

In order to prepare a multi-epitopeantigen of Porcine epidemic diarrheavirus(PEDV) S1 gene chimerized with Norovirus( NoV)P particles. The PEDV S1 multi-cpitope gene sequence was designed and synthesized, enzymatically ligated into the recombinant pGEX-4T-1vector of the NoV P gene,transformed the vector into E.coli DH5a receptor cells,and extracted the plasmid for double digestion verification and sequencing. The correctly sequenced recombinant plasmids were transformed into BL21-expressing organisms, and the recombinant proteins were analyzed for solubility using different concentrations of Isopropyl-β-D-thiogalactopyranoside (IPTG)at different induction times to determine the optimalinduction conditions. Western blot detection of purified recombinant proteins using murine Glutathione-S-transferase (GST) monoclonal antibody and PEDV-positive serum. The recombinant plasmid NoV P-partical-PEDV-SE was identified by double digestion and a larget gene band of proximately 510 bp in size was obtained. The molecular mass of the induced recombinant protein was about 79 ku, which was consistent with the expected size. The recombinant protein was expressed in the supernatant after sonication of the fragmented bacterium using 1. 0 mmol/LIPTG at 37 ℃ for 2 h as the optimal induction condition. Both murine-derived GST monoclonal antibody and PEDV-positive scrum specifically recognized the purified recombinant protein, indicating that the recombinant protein had good reactogenicity. In this study,a large amount of recombinant protein with high purity was successfully obtained by in situ expression and purification of NoV P-partical-PEDV-SEprotein,which is the basis for further preparation of a multi-epitope oral vaccine against PEDV in pigs.

In order to understand the drug resistance of Nocardia seriolae from hybrid snakehead in the Pearl River Delta region of Guangdong Province,the research group conducted an epidemiological survey of hybrid snakchead from March 2021 to July 2022. A total of 127 strains of pathogenic bacteria were isolated from hybrid snakehead, including 42 strains of N. seriolae. The drug resistance of 27 strains of N.seriolae was analyzed. The results showed that N.seriolae could be isolated throughout the year, accounting for 33. 1% of all isolated strains. The majority of N.seriolae strains were sensitive or resistant to the same drug, e. g.completely resistant to β-lactams (100%)，and sensitive to macrolides (85.2%).Some strains in Foshan arca were more resistant than those in Zhongshan arca, and all the strains were multi-drug resistant. The overall drug resistance spectrum of N. seriolae was similar, and the multi-drug resistance was serious. There were some differences in the drug resistance of some strains in Foshan and Zhongshan areas. This study provides a reference for the precise medication of hybrid snakehead nocardiosis.

In order to provide strain resources for detoxification of fusaric acid(FA)-contaminated soiland feed, soil samples were collected from banana rhizosphere soil in the field where fusarium wilt occurred, An FA degrading bacterium FAD1 was isolated by enrichment culture. Through the observation of colony morphological characteristics and 16SrDNA gene sequence alignment, the strain FADIwas identified as Mycobacterium sp. , FAD1 was inoculated into the medium with FA as the sole carbon( C) or nitrogen (N) source to observe its growth characteristics. The degradation effect of FAD1 on FA was evaluated by high performance liquid chromatography( HPLC) and plant in vivo test. The results showed that FAD1 could grow in the medium with FA as the sole source of C or N, and the degradation effect of FA was the best in the medium with FA as the sole source of Nor additional sources of Cand N.The HPLC results showed that the degradation rate of FA was up to 89% when FAD1 was cultured in FA con- taining medium until the decline phase. Plant in vivo test showed that tomato (Solanumlycopersicum ) seedlings lost turgid pressure and died of leaf water loss after soaking in MMF medium containing FA without FAD1 fermentation for 40 h, while seedlings treated after FAD1fermentation survived. In conclusion，FAD1 can grow in the culture medium with FA as the sole source of C and N.FAD1 can degrade FA to a certain degree, which has a application value in preventing the harm of FA to plants,animals and microorganisms.

Understanding the current situation of plant resources is of great significance to the community composition，structural characteristics and change trend of local plants. This paper used the forest plant community on the coast of Dameisha, Shenzhen as the research object. Bascd on sample method, x2test and principal component analysis method, the community characteristics of Dameisha coastal forest plants were revealed. The results show that there are 172 genera and 228 species of 83 vascular plants in the sample area of 4 400 m2; of which there are 162 genera of angiosperms, 211 species in 74 families,2 genera and 3 species of gymnosperms, and 14 species in 7 families of ferns. The species richness index is shrub layer > tree layer > herbal layer Schefflera rubriflora and Machilus chinensis are the main group specics. Psychotria asiatica and Liriope spicata are dominant species in the shrub layer and herb layer,respectively. The proportion of the middle path level ( DBH < 20 cm) is high, and the phenomenon of community stratified formation is not obvious. The appearance of the community is a subtropical evergreen broad-leaved forest.The overall connection among dominant spccics of the tree layer is not significantly positively connected, and the community stability is low. The coastal forest plant community in Damesa Scenic Area is unstable, and some areas are man-madely disturbed. In order to promote the construction of coastal forest vegetation, it is recommended to combine forest phasc transformation and local advantageous species planting, such as Machilus chinensis,Triadica cochinchinensis and so on.

The bryophyte resources in Jiucaiping arca of Haozhang County,Bijic City,Guizhou Province were investigated. The leaves were branched and separated under a magnifying lens, and the appearance, stem surface structure, leaf shape and leaf structure of the plants were observed.By comparing with related books and documents, it was found that there were 13 families, 20 genera and 28 species of bryophyte in this area, of which 17 species were unclear. The leaf morphology, the size, shape and distribution of the gametophytes of the 17 species of bryophyte were observed and finally identified. It was determined that the 17 specics of bryophyte were Palamocladium euchloron, Eurhynchium eustegium,Rhynchostegium contractum, Rhynchostegium pallidifolium , Campylopus umbellatus, Campylopus gracilis, Campylopus schmidii, Vesicularia flaccida, Ectropothecium obtusulum , Entodon flavescens, Entodon challengeri, Bryum billarderi,Brachymenium capitulatum,Didymodonrigidulus,Didymodon ferrugineus, Brotherella fauriei and Trachypus humilis.

In this study, two different landforms of reclaimed paddy fields in Nanxiong,Shaoguan, and Qingcheng Guangdong,Qingyuan were taken as examples. The rapid construction of impermeable layer and soil characteristics were analyzed by water injection and harrowing, in-situ grouting and adding foreign soil. The water retention rate of Qingcheng project can reach 55% by mixing 10% of the soil, and the water retention rate of Nanxiong project can meet the water retention requirements by water injection and harrowing, and the water retention rate is above 50% . After the impermeable layer was constructed,the soil bulk density of the impermcable layer in Qingcheng was 1.55 ~1. 72 g/cm3, while that in Nanxiong was 1.53 ~1.61 g/cm. The soil texture of the impermeable layer in Qingcheng is loam, while that in Nanxiong is sandy loam. However, the content of sand particles larger than 2 mm in the impermeable layer in Qingcheng is twice than that in Nanxiong. The saturated hydraulic conductivity of Qingcheng impermeable layer is0.010~0.020mm/min.While that of Nanxiong impermcable layer is 0.045~0.113mm/min. The research proves that even sandy loam can meet the waler relention requirements of paddy fields through water injection and harrowing or mixing process, so that the soil has the function of impermeable layer and tillage layer. More comprehensive analysis should be carried out on the qualitative analysis of soil, especially the consideration of the water retention effect of impermeable layer with large particle size sand and clay content.

Prunus x blireana ‘Meiren’twigs cuttings were treated with 200mg/L ABT rooting agent,and water treatment was used as a control to compare and analyse the changes in external morphology,nutrient content, antioxidant enzyme activity and endogenous hormone content of the cuttings during rooting.The results showed that: (1) the overall time required for cuttings to form a large number of adventitious roots from the beginning of cutting was about 28 d; (2) ABT had a significant favourable effect on the rooting of cuttings; (3)the soluble sugars,soluble protcins，Proline(Pro)，growth hormone ( Indole-3-acetic Acid, IAA) and Gibberellins (GA) content were significantly higher than CK after the late stage of cutting; (4) for the trend of Superoxide Dismutase(SOD) activity，there was no significant difference between treatments and CK. Through the analyses, it can be concluded that the rooting of Prunus x blireana‘Meiren’requires high content of IAA and low content of GA,and higher levels of soluble sugars and soluble proteins in the carly stage can promote the induction and development of adventitious roots. The accumulation of soluble sugars and soluble proteins in ABT-treated cuttings was significantly increased in the middle and late stages of cutting, while the contents of IAA and GA were also increased, which effectively balanced the endogenous hormone levels of the cuttings and provided favourable conditions for the growth of adventitious roots.

The effects of different media combinations on the growth of Dendrobium wardianum Warner tissue culture seedlings were compared using the sterile seedlings of Dendrobium wardianum Warner as the test material. The results showed that the most suitable medium for the protocorm-like bodies(PLBs) of Dendrobium wardianum Warner was MS +2.0mg/L 6-BA +1.0mg/L NAA+20.0 g/L Su, the most suitable medium for the proliferation of clustered buds was MS+0.3 mg/L NAA +30.0 g/L Su +1.0g/L activated carbon, and the most suitable medium for rooting tufted buds was 1/2 MS +1.0mg/L 6-BA+ 0.5 mg/L NAA +30.0 g/L Su+2.5g/L banana flour +1 g/L activated carbon.