Callerya speciosa is an important perennial medicinal and edible plant, with starch and saccharides as the main contents. This study investigated the development law of starch and sucrose metabolism pathways of C. specisoa at different developmental stages and its internal gene regulatory network. Four growth years of C. speciosa roots, including 3-year-old (NG3), 7-year-old (NG7), 10-year-old (NG10), and 15-year-old (NG15), were used as the research objects. The content of total polysaccharide, starch, and sucrose was determined, and transcriptome sequencing was carried out. Differentially expressed genes (DEGs) between different years were screened, and the functions of DEGs in the starch and sucrose metabolism pathways were focused on. The results showed that with the increase of years, the content of total polysaccharides and starch both showed an increasing trend, with the highest content at 15 years, while the sucrose content was the highest at 3 years, followed by a downward trend. Through transcriptome sequencing, NG3 was compared with NG7, NG10, and NG15, respectively, for intergroup gene expression analysis. With the increase of the growth year span, the total number of DEGs increased. To further explore DEGs in the starch and sucrose metabolism pathways, a total of 62 DEGs were differentially expressed in the three comparison groups, mainly participating in the regulation of starch, sucrose, and cellulose metabolism. Among them, the expression of sucrose synthesis genes decreased with the increase of years; the expression of starch synthesis genes dominated over starch degradation genes with the increase of years; and the expression of cellulose degradation enzymes decreased with the increase of years. Five key genes in the starch and sucrose metabolism pathways were screened out for fluorescence quantitative PCR verification, and the expression trend was basically consistent with the transcriptome sequencing results. The results indicate that C. speciosa is in the growth active period from 3 to 7 years, with the synthesis of sucrose, cellulose, and starch as the main promoters for rapid root expansion and development. When it grows to 7 years, the plant enters a stable growth phase characterized by starch accumulation, sucrose decomposition, and cellulose degradation. This research would provide valuable insights on the study of C. speciosa root expansion mechanism, the innovation of high-yielding varieties, and scientifically guided harvesting practices.

Nervilia plicata is a rare southern Chinese herb. The study on the plant at molecular level is hardly seen. Real-time quantitative PCR (qRT-PCR) has been widely used in plant gene expression analysis, but there is a lack of research on it in N. plicata, which limits the progress of related work. Based on the previous researches, nine candidate reference genes, including Actin, GAPDH, TUA, UBC, UBQ, EF-1α, EF-1β, CYP and RPL, were screened out from the transcriptomic sequencing data. In order to select suitable reference gene in N. plicata, qRT-PCR technique was employed to detect the expression levels of the candidate reference genes in leaf, petiole and corm tissues of the plant. After analyzing the expression levels, the stability and comprehensive analysis of nine genes in different tissues, the most suitable reference gene was obtained. Finally, the most suitable reference gene was validated using NpDFR, Np3GT that related to anthocyanin synthesis. Results showed that the expression stability of EF-1 α and CYP was similar, with the best overall stability. When using either EF-1α or CYP, or the combination of them, as reference, the expression patterns of NpDFR and Np3GT in different tissues were consistent with the transcriptome sequencing results. This indicates that both EF-1 α and CYP can be used as reference genes in N. plicata for qRT-PCR. This study would provide a basis for further research on the molecular mechanism of genes related to the pharmacological effects of N. plicata.

Broomcorn millet (Panicum miliaceum L.) is a traditional grain crop in China. Currently, there is still limited research on the genetic transformation methods for P. miliaceum. This study aimed to establish an efficient genetic transformation method for P. miliaceum mediated by Agrobacterium. Mature seeds of the millet variety Jishu 5 were used as the explants to induce embryogenic callus of millet on CIM and MSD induction media, respectively. They were used as the transformation receptor materials and infected with Agrobacterium containing plant expression vectors for 60 minutes and co-cultured for 6 days. The calli were then transferred to a screening medium containing 0.025 g/L of hygromycin to screen for resistant calli. Then, they differentiated on a differentiation medium containing 0.015 g/L of hygromycin. Finally, they rooted into seedlings on a rooting medium containing 0.015 g/L of hygromycin. PCR detection was performed on the regenerated plants using vector specific primers to identify whether they were positive transgenic plants. Based on the multiple batches of transformation experiments, the screening efficiency and transformation efficiency of resistant regenerated plants of broomcorn millet were statistically analyzed. The results showed that both CIM and MSD media could induce embryogenic callus of broomcorn millet, but CIM medium had a better effect on inducing embryogenic callus of broomcorn millet. After being infected by Agrobacterium and co-cultured with Agrobacterium, the multiple resistant regenerated plants were obtained through screening, differentiation, and rooting on a medium containing hygromycin. The PCR identification positive rate of the resistant regenerated plants obtained from three experiments was 100%, and the average transformation efficiency was over 30%. This study successfully established an Agrobacterium mediated genetic transformation method for broomcorn millet, which is simple to operate, efficient, cost-effective, and not limited by seasons. It could be carried out on a large scale, providing an effective technical means for genetic improvement of broomcorn millet.

Knowledge on germplasm resource information is the foundation for the genetic improvement of Aquilaria sinensis, and genome resequencing is a powerful tool for analyzing the genetic diversity of germplasm resources. However, there is no research on the genetic diversity of A. sinensis using genome resequencing. Based on the collection of A. sinensis germplasm resources in the early stages, this study utilized genome resequencing to obtain 1284 Gb of resequencing data from 60 samples of A. sinensis. Using the agarwood genome, 6 716 166 high-quality variation sites were detected, including 6 284 344 SNP sites and 428 658 Indel sites. Principal component analysis, phylogenetic analysis, and genetic structure analysis all indicated that A. sinensis could be divided into three distinct groups (Pop1, Pop2 and Pop3), with two of the groups further subdivided into multiple subgroups. Population selection signals were detected in all the groups, with Pop3 showing the highest frequency of selection signals. However, nucleotide polymorphism calculations indicated that Pop3 had the lowest nucleotide polymorphism. This study would provide valuable information for exploring the genetic resource diversity of A. sinensis and lay a theoretical foundation for genome-based genetic breeding of A. sinensis.

Using 77 Cymbidium ensifolium germplasms as the test materials, the phenotypic diversity of 21 quantitative traits and 12 qualitative traits was analyzed. The results showed that the coefficient of variation (CV) for quantitative traits ranged from 14.72% to 42.79%, indicating a significant degree of variation. Among these, the CV value for flower length was the lowest (14.72%), suggesting that this trait was relatively stable across different germplasms. The CV value for the number of flower stalks was the highest (42.79%), followed by the number of flowers (41.67%). Additionally, the Shannon-Wiener index (I) was close to 5, indicating a high level of diversity in quantitative traits among the germplasms. In the binary analysis of qualitative traits, the distribution of sepal spots or stripes (colors) among the germplasms was similar, with a rich variety of expressions for the features on the flower sepals. The CV for qualitative traits ranged from 9.86% to 83.81%, also showing a significant degree of variation. Among these, the CV value for leaf posture was the lowest (9.86%), while the CV values for lip shape (83.81%) and sepal color (70.69%) were the highest. Furthermore, the I index values for qualitative traits ranged between 4 and 5, indicating a high level of diversity in qualitative traits among the germplasms. The Simpson index (D) for qualitative traits ranged from 0.985 to 0.991, close to the value of 1, suggesting a relatively uniform distribution of qualitative traits and a high degree of diversity among the germplasms. Principal component analysis was conducted on 33 phenotypic traits of the germplasms, and the first 10 principal components were extracted based on the criterion that the characteristic root value is greater than 1. The characteristic value of the first 10 principal components was 6.406, 4.475, 2.840, 2.425, 2.139, 1.619, 1.517, 1.430, 1.163, and 1.038, with a cumulative contribution rate of 75.917%. The number of flower parts among the phenotypic traits had a significant weight in the principal components, indicating it is a major phenotypic trait of C. ensifolium. Hierarchical clustering analysis was performed on the germplasms using Euclidean distance, resulting in a dendrogram. At the 15th Euclidean distance, the germplasms were clustered into five major groups, with the main features of phenotypic traits concentrated in quantitative traits, especially in the significant weight of the number of flower parts, consistent with the results of the principal component analysis. This study explored the genetic diversity and relationships among C. ensifolium varieties through morphological trait diversity analysis, providing a basis for the scientific management and conservation of C. ensifolium germplasm resources. It also offers valuable genetic materials for future C. ensifolium breeding work.

Bougainvillea is an important woody ornamental plant in southern China. There are a large number of varieties, but the classification is relatively chaotic. This study took 133 Bougainvillea varieties introduced and preserved in Yunnan as the research object, and conducted frequency distribution statistical analysis, coefficient of variation calculation, and diversity index calculation for 10 quantitative characters and 41 discrete characters. Q-type clustering analysis was also conducted. The results showed that the 133 Bougainvillea varieties had rich diversity in many characters, and the coefficient of variation of quantitative characters ranged from 19.61%–32.59%, with an average of 26.64%. The coefficient of variation of the total flower stem length, calyx tube width, petiole length, and flower length was the highest, and the diversity index ranged from 1.69–2.09, with an average of 1.92. The diversity index of leaf length, bract width, leaf width, and bract length was the highest. The diversity index of discrete characters ranged from 0.17–2.19. There were 11 discrete characters with H′ values greater than 1, and the diversity index of bract color and calyx tube color was both greater than 2. The diversity was rich. Among the four species of Bougainvillea, the diversity index of Bougainvillea×buttiana was the highest, with the richest diversity, followed by B. peruviana, B. glabra, and B. spectabilis, whose diversity index was the lowest, with less diversity. However, each species has its own advantageous characters. Among the 51 characters, 22 characters showed significant difference among species, which were of great reference value for identifying and classifying the varieties of Bougainvillea. Based on the types of bracts, the number of spines, and the size of leaves, 133 B. varieties could be grouped into four categories: double spiny less, double spiny more, single spiny less leaflet, and single spiny large leaflet. The research results show that the phenotypic characters of the 133 B. varieties tested have high diversity, and the quantitative trait variation types are rich. This study could provide scientific basis for systematic evaluation of B. germplasm resources, variety classification, and germplasm innovation.

Crossbreeding research for Camellia species groups and intragroups was carried out to breed new varieties of Camellia with high ornamental value. A total of 14 species and varieties from Sect. Chrysantha Chang, Sect. Camellia (L.) Dyer, Sect. Archecamellia Sealy and Sect. oleifera Chang, Sect. Corallina Sealy were used to design 42 hybridization combinations, including 8 hybridization of species groups, 24 intragroup hybridization and 10 reciprocal hybridization combinations. 274 setting fruits from 2016 flowers pollinated in 42 combinations were observed, and the percentage of fruit setting rate was 13.6%. 72 hybrid fruits were harvested, and the setting rate was 3.57%. 104 hybrid seedlings were obtained from the 199 seeds harvested, and the seedling emergence percentage was 52.26%. The combination of C. polyodonta♀×C. semiserrata♂ had the highest number of hybrid seedlings, reaching 45, followed by C. semiserrata♀×C. polyodonta♂ with 14 hybrid seedlings, C. polyodonta♀×C. amplexicaulis♂ with 13 hybrid seedlings. The size, shape and luster of the leaves of most hybrid seedlings were in the middle of the parents, and the hybrid seedlings obtained from distant hybridization often showed some characteristics that could be used as early identification of the authenticity of hybrid seedlings. The compatibility of C. polyodonta♀×C. semiserrata♂, C. polyodonta♀×C. amplexicaulis♂, and C. polyodonta♀×Camellia chrysantha♂ hybrid combinations was good, with pollination numbers of 32, 30, and 53, respectively, and seed setting rates of 12.5%, 10.0%, and 22.6%, respectively. More pollination numbers led higher seed setting rate and stronger representativeness. C. polyodonta and C. semiserrata could be used as paternal or maternal to cross breeding, which showing a high reproduction in the inside group of hybridization and outside group of distant hybridization. C. polyodonta and C. semiserrata were good hybrid parents. whether C. amplexicaulis as paternal or maternal parent, there was good cross compatibility with Sect. C. chrysantha and C. osmantha were suitable as paternal parents.

Guangxi spans the southern subtropics and central subtropics, with the Tropic of Cancer crossing the central part of the province, and belongs to the subtropical monsoon climate zone, which breeds rich wild sugarcane germplasm resources. From 2016 to 2023, Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences organized a team of researchers to carry out systematic surveys and collection of Narenga porphyrocoma germplasm resources in Guangxi. The team collected a total of 58 copies of N. porphyrocoma germplasm resources in 43 townships of 18 cities and districts in Guangxi. The results showed that the N. porphyrocoma germplasm resources in Guangxi were mainly distributed in the area of 60.0-602.5 m above sea level, longitude E: 107°08′01″-111°32′02″, latitude N: 23°08′02″-26°01′43″. The genetic diversity indices of the 20 descriptive quality traits of N. porphyrocoma germplasm resources in Guangxi ranged from 0 to 1.2044, with a mean value of 0.5557, in which the diversity of the color of the internodes after exposure was the highest, that of the cork was lower, and the diversity of the three traits of stem shape, aerial roots and water splitting was not reflected; the genetic diversity indices of N. porphyrocoma germplasm resources in Guangxi of the different collection areas ranged from 0.1040 to 0.4911, with Hezhou being the highest and Baise being the lowest. The phenotypic traits of N. porphyrocoma germplasm resources in Guangxi were rich in variation, and the coefficients of variation for six quantitative traits ranged from 17.3% to 53.6%, with an average of 34.8%; the coefficients of variation of N. porphyrocoma germplasm resources in Guangxi from different collection areas ranged from 29.4% to 36.9%, with Hechi being the largest and Guilin being the smallest. The results of cluster analysis showed that the 58 N. porphyrocoma germplasm resources in Guangxi were classified into six major groups, but were not closely related to the geographical origin, in which the materials in the first major group had better overall traits and excellent biomass and quality traits. The collection expanded the number of resources in Guangxi Sugarcane Germplasm Repository and would provide excellent genetic resources for sugarcane breeding and genetic improvement.

Luffa, a major melon vegetables in China, is a crop of gourd family and the silk gourd genus, which is rich in nutrients and favored by consumers. With the increasing number and type of luffa germplasm resources, it is increasingly difficult to screen and preserve the excellent materials of luffa. In order to construct a core germplasm bank of luffa, eliminate germplasm materials with serious homogenization, and improve the efficiency of lucerne breeding, this study investigated the genetic diversity of 244 luffa germplasm resources by using 18 phenotypic traits that are highly representative of luffa as indicators, and compared and analyzed eight different sampling ratios (5%-40%), and three different sampling methods (random cluster sampling, group cluster sampling and preferential cluster sampling) were compared to analyze the representativeness of the core germplasm of luffa candidates. The results showed that the phenotypic genetic variation of lucerne germplasm resources was relatively rich, of which the largest Shannon index was leaf width, 3.0, and the smallest was seed melon length, 1.8. The most suitable sampling ratio was 20% using the comprehensive analysis of the seven evaluation indexes, and the most suitable sampling method was group cluster sampling. Using this method for core germplasm library construction, the primary core germplasm obtained containing 51 lucerne germplasm resources, accounting for 20.90% of all the original germplasm resources, and compared with the original germplasm, 13 of the 18 agronomic traits were in full agreement with the original germplasm in terms of the maximum and minimum values, and the characteristic values of most traits were the same as those of the original germplasm or the differences were relatively small. The T-test showed that the mean values of all phenotypic traits had no significant differences with the original germplasm, indicating that the core germplasm library constructed by the method has good representativeness and rich genetic diversity. This study could provide basic support for the collection, preservation and innovative utilization of lucerne germplasm resources in the later stage, and also lays a foundation for improving the efficiency of lucerne variety improvement.

The present study investigated the effects of chemical fertilizer reduction patterns on the growth, field propagation efficiency, and fertilizer utilization rate of disease-free sugarcane original seedlings to provide a theoretical basis for the application of mulched drip fertigation, and to identify the optimal pattern for reducing fertilizer in the field propagation of disease-free sugarcane original seedlings. Under the condition of drip irrigation management, six different treatments were set: no fertilization (CK₀), conventional fertilization (CK₁), mulched drip fertigation T₁₀₀ (fertilizer amount equated with CK₁) and T₈₀, T₇₀, T₆₀ (20%, 30% and 40% reduction of the fertilization rate in T₁₀₀). A comparative analysis was done on the main agronomic traits, total bud count per unit area, propagation efficiency, economic benefit, and nutrient utilization rate during the field propagation of disease-free sugarcane original seedlings. The results showed that the two-year average tillering rate in the treatment T₁₀₀ and T₈₀ was slightly lower than that in CK₁. However, significant improvement was observed in the stalk formation rate, the number of buds per plant, and the number of millable stalks compared to CK₁ Notably. T₁₀₀ and T₈₀ exhibited the highest values for the total number of propagation buds, with averages 1.4809 million buds/hm² and 1.4779 million buds/hm², respectively in two years, both significantly exceeding the 1.3025 million buds/hm² in CK₁. In contrast, there was no significant difference between T₇₀ and CK₁, while T₆₀ had the lowest value of only 1.1705 million buds/hm². T₁₀₀ and T₈₀ showed the highest field propagation multiples of original seedlings, reaching 66.64 and 66.50 times, respectively, followed by T₇₀ and CK₁ with propagation multiples of 59.61 and 58.61 times, respectively, and T₆₀ had the lowest propagation multiple of 52.67. Compared to CK₀ without fertilization, T₁₀₀ and T₈₀ achieved the highest income increase, reaching 58 200 and 58 700 Yuan/hm², respectively, followed by T₇₀ with an income increase of 41 900 Yuan/hm² which was slightly higher than CK₁'s 38 400 yuan/hm²; T₆₀ had the lowest income increase of only 25 100 Yuan/hm². Regarding the fertilizer input-output ratio, T₈₀ had the highest ratio of 1∶21.89, significantly exceeding that of 1∶17.36, while CK₁ had the lowest ratio of 1∶11.45. Among all the fertilization treatments, CK₁ had the lowest utilization rates of nitrogen, phosphorus, and potassium fertilizers. Furthermore, T₈₀ boasted the highest fertilizer utilization rates, with 51.57% for nitrogen, 27.37% for phosphorus, and 67.45% for potassium in two-year averages, which was 21.21%, 10.37%, and 23.13% higher than those in CK₁, respectively. In conclusion, for laterite soil with medium fertility, the mulched drip fertigation pattern T₈₀ performed the best in field propagation efficiency and economic benefits for disease-free sugarcane seedlings.