To investigate carbon storage and distribution characteristics of Camellia gauchowensis plantation, estimate and evaluate the effect of carbon sequestration.

Based on the distribution characteristics of basic diameter class in the sample plot, 2 to 3 sample trees were selected in each diameter class. The biomass and carbon content of various organs (leaves, trunks, branches, roots, fruits and flower buds) were measured and their biomass models were established. According to “S” shape in standard plot, eight sampling points were randomly selected to collect soil samples from 0−20, 20−40, 40−60 and 60−100 cm along the soil profile. The bulk density and carbon content of soil samples were determined and the carbon storage was calculated.

The order of biomass allocation ratio of the organs of middle-aged C. gauchowensis plantation was trunks> roots > leaves > branches > fruits > flower buds. All the biomass of various organs increased with the basal diameter. The total biomass of test stand was 26.902 t·hm⁻². The average carbon content of the tree was 483.45 g·kg⁻¹. The carbon contents were different from various organs in the same diameter class, with fruits being the highest. In the soil layers of 100 cm depth in C. gauchowensis forest land, the soil carbon content decreased with the increase of soil depth, with 0−20 cm soil layer being the highest (26.550 g·kg⁻¹). The total carbon storage of C. gauchowensis plantation was 144.538 t·hm⁻², which was 12.857 t·hm⁻² (accounting for 8.90%) and 131.681 t·hm⁻² (accounting for 91.10%) for plant and soil, respectively. According to the authorized data of China biodiversity national condition report, the carbon price is 260.90 CNY per ton, so the economic benefit of the carbon of C. gauchowensi plantation is about 38 000 CNY per hectare.

The carbon storage of C. gauchowensis plantation is higher than that of the average level of non-timber forests in Guangdong, the forest soil carbon storage is higher than the average level in Guangdong, and the total carbon storage of stand is higher than that of forest ecosystem in the Pearl River Delta. C. gauchowensi not only has a good production benefit, but also has a very broad prospect of carbon sequestration.

To systematically analyze and compare the diversity of endophytic fungi from wild and cultivated Dendrobium officinale, and screen fungal strains with anti-anthracnose activities.

Endophytic fungi of D. officinale were isolated by tissue block separation method, and they were identified by slide culture method and molecular identification method based on internal transcribed spacer regions of ribosomal DNA (rDNA-ITS). Screening for endophytic fungi against anthracnose was carried out by plate method.

Totally 236 endophytic fungal strains were isolated from D. officinale(132 from wild plants and 104 from artificially cultivated plants). Total colonization rate (50.46%), total isolation rate (61.11%) and diversity index (2.95%) of endophytic fungi in wild plants were significantly higher than those in artificially cultivated plants (the corresponding values were 39.35%, 48.14% and 2.49, respectively). We screened out 34 strains of endophytic fungi with inhibitory activities against Colletotrichum gloeosporioides. Amomg them, the strains Ceriporia sp. F102, Rigidoporus sp. F27, Termitomyces sp. F103 and Peniophora sp. F122 showed higher inhibitory effects, and their inhibition rates were 93.06%, 88.20%, 87.48% and 84.57%, respectively.

The biodiversity and community structure of endophytic fungi of wild D. officinale and artificially cultivated D. officinal had significant differences, and abundant strains with anti-anthracnose activities were obtained from them, which lays the foundation for improving the quality of medicinal materials of artificially cultivated D. officinal and the biocontrol of D. officinale anthracnose.

To obtain a rabbit model of Tiki1 gene knockout by the transcription activator-like effector nuclease (TALEN) system, and provide a rabbit model for investigating the mechanism of Tiki1 gene on early development of animals.

Using TALEN system, the target vector of rabbit Tiki1 gene was constructed and then 10 or 50 ng/μL Tiki1-TALEN mRNA was injected into the cytoplasm of fertilized eggs at pronuclear stage. Embryos developed to blastocyst stage were collected. The blastocyst rate and gene modification efficiency were investigated. To further obtain Tiki1 knockout rabbits, 50 ng/μL Tiki1-TALEN mRNA was subsequently injected into the cytoplasm of 17 prokaryotic fertilized eggs of rabbit, and then the fertilized eggs were transplanted into two recipient rabbits.

The blastocyst rate of the treatment group injected with 50 ng/μL Tiki1-TALEN mRNA（64%) was almost the same as that of the group injected with 10 ng/μL Tiki1-TALEN mRNA(57%), while the blastocyst gene modification efficiency of the group injected with 50 ng/μL Tiki1-TALEN mRNA(100%) was significantly higher than that of the group injected with 10 ng/μL Tiki1-TALEN mRNA (14.3%). The sequencing results showed that mutations of Tiki1 gene ranged from the deletion of 1 bp to 28 bp. A total of three rabbits were born after embryo transfer, and two of them were detected with genetic mutations.

The TALEN technology system established in this study could effectively knock out Tiki1 gene in rabbit.