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Camellia oleifera is a woody oil crop with the highest oil yield and the largest cultivation area in China, and C. oleifera seed oil is a high-quality edible oil recommended by the Food and Agriculture Organization of the United Nations. The objectives of this study were to investigate the variation in fruit yield traits and seed chemical compositions of wild C. oleifera in China and to identify the differences between wild C. oleifera and cultivated varieties. In this study, we collected wild C. oleifera samples from 13 sites covering the main distribution areas of wild C. oleifera to comprehensively evaluate 25 quantitative traits of wild C. oleifera fruit and seed chemical compositions and collected data of 10 quantitative traits from 434 cultivated varieties for a comparative analysis of the differences between wild and cultivars. The results showed that the coefficients of variation of the 25 quantitative traits of wild C. oleifera ranged from 2.605% to 156.641%, with an average of 38.569%. The phenotypic differentiation coefficients ranged from 25.003% to 99.911%, with an average of 77.894%. The Shannon–Wiener index (H') ranged from 0.195 to 1.681. Based on the results of principal component analysis (PCA) and phenotypic differentiation coefficients, 10 traits differed significantly between wild C. oleifera and cultivated varieties, while the differentiation coefficients (VST) for fresh fruit weight, oleic acid, unsaturated fatty acids, stearic acid, and saturated fatty acids were more than 95%, of which fresh fruit weight and oleic acid content were potential domestication traits of C. oleifera. The results of this study can contribute to the efficient excavation and utilization of wild C. oleifera genetic resources for C. oleifera breeding. [ABSTRACT FROM AUTHOR]

Camellia oleifera is a medicine food homology plant widely cultivated in the Yangtze River Basin and southern China due to its camellia oil. Camellia oleifera bud and fruit exist simultaneously, and its bud is largely discarded as waste. However, C. oleifera bud has been used in traditional Chinese medicine to treat a variety of ailments. Thus, the purpose of this study was to identify the chemical components of C. oleifera bud ethanol extract (EE) and first evaluate its anticancer effects in non-small cell lung cancer A549 cells. Based on UHPLCQ-Orbitrap-MS analysis, seventy components were identified. For anticancer activity, C. oleifera bud EE had remarkable cytotoxic effect on non-small cell lung cancer A549 (IC50: 57.53 ± 1.54 µg/mL) and NCI-H1299 (IC50: 131.67 ± 4.32 µg/ mL) cells, while showed lower cytotoxicity on non-cancerous MRC-5 (IC50 > 320 µg/mL) and L929 (IC50: 179.84 ± 1.08 µg/mL) cells. It dramatically inhibited the proliferation of A549 cells by inducing cell cycle arrest at the G1 phase. Additionally, it induced apoptosis in A549 cells through a mitochondria-mediated pathway, which decreased mitochondrial membrane potential, upregulated Bax, activated caspase 9 and caspase 3, and resulted in PARP cleavage. Wound healing and transwell invasion assays demonstrated that C. oleifera bud EE inhibited the migration and invasion of A549 cells in a dose-dependent manner. The above findings indicated that C. oleifera bud EE revealed notable anticancer effects by inhibiting proliferation, inducing apoptosis, and suppressing migration and invasion of A549 cells. Hence, C. oleifera bud ethanol extract could serve as a new source of natural anticancer drugs. [ABSTRACT FROM AUTHOR]

Background: Camellia oleifera, an essential woody oil tree in China, propagates through grafting. However, in production, it has been found that the interaction between rootstocks and scions may affect fruit characteristics. Therefore, it is necessary to predict fruit characteristics after grafting to identify suitable rootstock types. Methods: This study used Deep Neural Network (DNN) methods to analyze the impact of 106 6-year-old grafting combinations on the characteristics of C.oleifera, including fruit and seed characteristics, and fatty acids. The prediction of characteristics changes after grafting was explored to provide technical support for the cultivation and screening of specialized rootstocks. After determining the unsaturated fat acids, palmitoleic acid C16:1, cis-11 eicosenoic acid C20:1, oleic acid C18:1, linoleic acid C18:2, linolenic acid C18:3, kernel oil content, fruit height, fruit diameter, fresh fruit weight, pericarp thickness, fresh seed weight, and the number of fresh seeds, the DNN method was used to calculate and analyze the model. The model was screened using the comprehensive evaluation index of Mean Absolute Error (MAPE), determinate correlation R2 and and time consumption. Results: When using 36 neurons in 3 hidden layers, the deep neural network model had a MAPE of less than or equal to 16.39% on the verification set and less than or equal to 13.40% on the test set. Compared with traditional machine learning methods such as support vector machines and random forests, the DNN method demonstrated more accurate predictions for fruit phenotypic characteristics, with MAPE improvement rates of 7.27 and 3.28 for the 12 characteristics on the test set and maximum R2 improvement values of 0.19 and 0.33. In conclusion, the DNN method developed in this study can effectively predict the oil content and fruit phenotypic characteristics of C. oleifera, providing a valuable tool for predicting the impact of grafting combinations on the fruit of C. oleifera. [ABSTRACT FROM AUTHOR]

Purple soils are greatly representative of ecologically fragile soils in southern China, yet the impact of vegetation restoration processes on the nitrogen (N) availability in purple soil ecosystems is still unclear. In this study, the soil nutrient content, available N fractions (including microbial biomass N (MBN), ammonium N (NH4+-N), nitrate N (NO3−-N), and total dissolved N (TDN)), and enzyme activities (including urease (URE), nitrate reductase (NR), and nitrite reductase (NIR)) involved in N mineralization and immobilization were investigated across the three vegetation-restoration measures: Camellia oleifera monoculture, Camellia oleifera ryegrass intercropping, and Camellia oleifera intercropping with weeds. The results showed that the Camellia oleifera monoculture mode considerably enhanced the accumulation and availability of soil N and modified the proportion of available N fractions in arable land situated on purple soil slopes, compared to the intercropping mode, the physical, chemical, and microbiological properties of soil demonstrated more pronounced effects due to the Camellia oleifera monoculture vegetation-restoration measures. However, soil nutrient loss is faster on set-aside land and in crop monocultures, and intercropping restoration measures are more beneficial for soil and water conservation under timely fertilization conditions. The soil URE, NR, and NIR activities and MBN content in the Camellia oleifera monoculture model were significantly higher than in the control check sample. Soil N transformation occurs through the combined influence of chemical and biological processes. The relationships between the activities of the three soil enzymes studied and the contents of various components of soil nutrients and effective N displayed significant differences. Notably, URE had a highly significant positive correlation with TOC. There is a strong positive correlation between NR and TN, NIR and TDN, NO3−-N, and NH4+-N. Our findings suggest that vegetation restoration improved the soil N availability and its enzyme activities in purple soils, making an essential contribution to the restoration and sustainability of purple soil ecosystem functions. [ABSTRACT FROM AUTHOR]

Camellia oleifera Abel. is a unique woody edible oil tree species in China mainly distributed in red soil areas. Nitrogen is one of the important growth-limiting factors for C. oleifera, and the nitrogen form has a vital impact on the growth and development of the plants. Ammonium and nitrate are the two nitrogen forms that are maximally absorbed and utilized by the plants. Here, we used one-year-old seedlings of the main varieties of C. oleifera ('Xianglin No. 1', 'Xianglin No. 27', and 'Xianglin No. 210') to set up six experimental groups treated with different nitrogen forms ([ N O 3 − : N H 4 + ] 0:0, 10:0, 7:3, 5:5, 3:7, and 0:10) and investigated the effects of nitrogen on the vegetative growth and photosynthetic characteristics of the seedlings. This study showed that mixed nitrogen sources could significantly increase the seedling height, ground diameter, biomass accumulation, and photosynthesis efficiency. Transcriptome sequencing analysis led to the identification of 3561 differentially expressed genes in the leaves. Preliminary screening identified several key enzyme genes from nitrogen nutrient metabolic pathways that were differentially expressed among seedlings grown with different nitrogen forms, and their expression pattern changes were further characterized. All the results demonstrate that the same proportion of ammonium nitrate ratio promoted the expression of genes encoding glutamine synthetase and glutamate synthase, thereby improving nitrogen assimilation and utilization efficiency. This study could provide a theoretical basis for scientific and rational fertilization and the improvement of nitrogen utilization efficiency in C. oleifera seedlings. [ABSTRACT FROM AUTHOR]

As an important oil crop in China and the world, the harvesting problem of Camellia oleifera has attracted much attention. Research is needed on mechanical characteristics of harvesting equipment. Explicit dynamics was used to establish a finite element model under a simulated load response to the branch-pedicel-fruit system of C. oleifera to predict the fracture process at the pedicel junction. The separation mechanism of C. oleifera fruit was determined by measuring the constitutive parameters of fruit branches and pedicels and conducting separation experiments and explicit dynamics simulations on different hanging fruits. The maximum stress at the fruit pedicel was 1.14 MPa, and the goodness of fit between the simulation and experiment was approximately 89.5%, indicating that the branch-pedicel-fruit finite element model could accurately reflect the fruit shedding process and that the pedicel diameter was correlated positively with the separation force. This study provides technical parameters for the optimized design of existing C. oleifera harvesting equipment. [ABSTRACT FROM AUTHOR]

Persimmons (Diospyros) are economically important trees that are widely cultivated for wood production in China, and Diospyros oleifera Cheng is the main persimmon grafting stock. However, an efficient tissue culture system has not been perfected for D. oleifera due to the limits of proliferation and rooting cultures. Therefore, this study examined the effects of different plant growth regulators and concentrations on the primary culture of young embryos, induction of leaf callus, differentiation of adventitious shoots, and rooting culture of D. oleifera. The optimal formula for young embryo germination was 1/2 Murashige and Skoog (MS) medium containing 0.5 mg/L gibberellic acid (GA3); after 25 days, the sprouting rate of the young embryos was 67.3%. The best medium for leaf callus induction was 1/2MS medium containing 2.0 mg/L of 6-benzylaminopurine (6-BA) and 0.5 mg/L of naphthaleneacetic acid (NAA), and the callus induction rate was 88.9%. Then, the callus was transferred to 1/2MS medium containing 2.0 mg/L of zeatin (ZT), 0.5 mg/L of NAA, and 2.0 mg/L of thidiazuron (TDZ) to induce adventitious shoots; after 25 days, 5.4 buds were produced per explant, and the induction rate of the adventitious shoots was 88.3%. The adventitious shoots were transferred to 1/2MS medium containing 2.0 mg/L of ZT, 2.0 mg/L of 6-(γ,γ-dimethylallylamino)purine (2iP), and 0.1 mg/L of indole acetic acid (IAA) for the proliferation culture, for which the multiplication coefficient approached 7.5. After multiplication, the adventitious shoots were inoculated into 1/2MS medium containing 1.0 mg/L of indole butyric acid (IBA), 0.5 mg/L of NAA, and 1.0 mg/L of kinetin (KT); the rooting rate was 60.2%, and the average number of roots was 6.9. [ABSTRACT FROM AUTHOR]

Seed traits can influence post-dispersal seed fate and seedling establishment by manipulating the size of caches made by hoarding animals. However, few studies have explored how seed traits affect cache size and subsequent seed fate mediated by hoarding rodents. In this study, we investigated the effects of seed traits on hoarding behavior of Leopoldamys edwardsi using seeds of Quercus variabilis, Castanea henryi, Camellia oleifera, Lithocarpus harlandii, and Choerospondias axillaris in semi-natural enclosures in Dujiangyan, southwest China, in an attempt to elucidate the relationship between seed traits and cache size. Significant differences were detected in the scatter-hoarding preference of L. edwardsi for seeds of C. axillaris, C. henryi, C. oleifera, Q. variabilis, and L. harlandii. There was a significant difference in the cache size between the five seed species made by L. edwardsi. More importantly, we found that there was a significant positive correlation between the cache size and crude fat but a significant negative correlation between cache size and seed mass as well as crude starch. Our study has revealed that seed traits appear to be a key factor in regulating the hoarding behavior of rodents, mainly the size of their caches. This regulation, in turn, has a significant impact on seed survival and seedling establishment that emerge from the caches. Significance statement: At present, a large number of studies focus on a certain trait of a single seed or the effect of a certain seed trait of various species on the hoarding behavior of rodents. How seed traits affect cache size and subsequent seed fate mediated by hoarding rodents remains unknown. This study systematically illustrates how rodents manipulate seed fates and manage cache size according to seed traits. Managing cache size based on different seed traits involves a trade-off between cache recovery and pilferage, which may be an evolutionary strategy of scatter-hoarding animals. [ABSTRACT FROM AUTHOR]

Camellia seed oil is a top-end quality of cooking oil in China. The oil quality and quantity are formed during seed maturation and desiccation. So far, it remains largely unresolved whether lipid degradation occurs and contributes to Camellia oil traits. In this study, three different Camellia germplasms, C. oleifera cv. Min 43 (M43), C. meiocarpa var. Qingguo (QG), and C. meiocarpa cv Hongguo (HG) were selected, their seed oil contents and compositions were quantified across different stages of seed desiccation. We found that at the late stage of desiccation, M43 and QG lost a significant portion of seed oil, while such an event was not observed in HG. To explore the molecular bases for the oil loss In M43, the transcriptomic profiling of M43 and HG was performed at the early and the late seed desiccation, respectively, and differentially expressed genes (DEGs) from the lipid metabolic pathway were identified and analyzed. Our data demonstrated that different Camellia species have diverse mechanisms to regulate seed oil accumulation and degradation, and that triacylglycerol-to-terpenoid conversion could account for the oil loss in M43 during late seed desiccation. [ABSTRACT FROM AUTHOR]

Camellia oleifera Abel., which produces fruits of high comprehensive utilization value, is an important woody oil tree in China. ZEITLUPE (ZTL) is a blue light receptor and clock component protein that is involved in various physiological and biochemical processes. However, the expression pattern and function of C. oleifera ZTL (CoZTL) remain unclear. In this study, the coding sequence of the CoZTL gene was isolated and the protein function was explored using bioinformatics and expression analyses and heterologous expression techniques. The results showed that the CoZTL protein was highly conserved during evolution and was on the same branch of the evolutionary tree as the ZTL proteins from Ipomoea nil and Nicotiana attenuata. CoZTL was mainly expressed in the fruit shells and stems of C. oleifera, and its expression level fluctuated greatly during flower bud development. Transgenic CoZTL-overexpressing Arabidopsis plants showed delayed flowering under long-day conditions as well as light-dependent promotion of hypocotyl elongation. Furthermore, yeast two-hybrid library screening revealed that seven C. oleifera proteins (CoAAT, Coβ-GAL, CoLAT52-like, CoCAR4-like, CoAO, CoUQCC1, and CoADF 2) interacted with CoZTL. Our results indicate that CoZTL plays an important role in C. oleifera flowering and hypocotyl growth. [ABSTRACT FROM AUTHOR]

Oiltea-camellia (C. oleifera) is a widely cultivated woody oil crop in Southern China and Southeast Asia. The genome of oiltea-camellia was very complex and not well explored. Recently, genomes of three oiltea-camellia species were sequenced and assembled, multi-omic studies of oiltea-camellia were carried out and provided a better understanding of this important woody oil crop. In this review, we summarized the recent assembly of the reference genomes of oilteacamellia, genes related to economic traits (flowering, photosynthesis, yield and oil component), disease resistance (anthracnose) and environmental stress tolerances (drought, cold, heat and nutrient deficiency). We also discussed future directions of integrating multiple omics for evaluating genetic resources and mining key genes of important traits, and the application of new molecular breeding and gene editing technologies to accelerate the breeding process of oiltea-camellia. [ABSTRACT FROM AUTHOR]

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Camellia oleifera Abel. is an economically important woody oil plant native to China. To explore the genetic diversity of wild C. oleifera phenotypic traits and effectively protect these germplasm resources, this study provides a thorough evaluation of the phenotypic variability of a cluster of 143 wild C. oleifera germplasm resources. A total of 41 characters, including leaves, flowers, fruits, seeds, and oil quality characters, were investigated based on the quantization of physical and chemical descriptors and digital image analysis. The findings revealed significant variations among the 41 characters with a high range of Shannon-Wiener indexes (H') from 0.07 to 2.19. The coefficient of variation (CV) among 32 quantitative characters ranged from 5.34% to 81.31%, with an average of 27.14%. High genetic diversity was also detected among the 143 germplasm. Based on the analysis of hierarchical clustering, 143 accessions were separated into six categories. All the individuals can be clearly distinguished from each other according to the result of the principal component analysis (PCA). The MTOPSIS exhaustive evaluation method based on correlation and PCA analyses of 32 quantitative characters was applied for the 143 wild C. oleifera accessions, and the top 10 varieties were identified as YA53, YA13, YA40, YA34, YA57, YA19, YA33, YA41, DZ8, and YA7. This research optimized the germplasm evaluation system and perfected the statistical phenotypic traits for distinctness, uniformity, and stability (DUS) testing. Some top-notch germplasm sources were also screened for oil-tea Camellia breeding. [ABSTRACT FROM AUTHOR]

Camellia oleifera (C. oleifera) is a unique edible oil crop in China cultivated in the hilly southern mountains. Although C. oleifera is classified as a drought-tolerant tree species, drought remains the main factor limiting the growth of C. oleifera in summer and autumn. Using endophytes to improve crop drought tolerance is one effective strategy to meet our growing food crop demand. In this study, we showed that endophyte Streptomyces albidoflavus OsiLf-2 could mitigate the negative impact of drought stress on C. oleifera, thus improving seed, oil, and fruit quality. Microbiome analysis revealed that OsiLf-2 treatment significantly affected the microbial community structure in the rhizosphere soil of C. oleifera, decreasing both the diversity and abundance of the soil microbe. Likewise, transcriptome and metabolome analyses found that OsiLf-2 protected plant cells from drought stress by reducing root cell water loss and synthesizing osmoregulatory substances, polysaccharides, and sugar alcohols in roots. Moreover, we observed that OsiLf-2 could induce the host to resist drought stress by increasing its peroxidase activity and synthesizing antioxidants such as cysteine. A multi-omics joint analysis of microbiomes, transcriptomes, and metabolomes revealed OsiLf-2 assists C. oleifera in resisting drought stress. This study provides theoretical and technical support for future research on endophytes application to enhance the drought resistance, yield, and quality of C. oleifera. [ABSTRACT FROM AUTHOR]

The grey blight disease is a common disease of tea plants and camellias (Camellia spp.). It is caused by Pestalotiopsis‐like fungi, which were mostly identified as species of Pestalotiopsis and Pseudopestalotiopsis. In this study, four strains of Neopestalotiopsis were isolated from brown and grey‐white spots of leaves of Camellia oleifera and C. sasanqua in China. These strains belong to Neopestalotiopsis longiappendiculata and are characterized by morphology and multi‐loci phylogenetic analysis (ITS‐tef‐tub2). This is the first report of N. longiappendiculata as agent of grey blight disease on Camellia spp. Pathogenicity tests indicated that N. longiappendiculata infects not only Camellia oleifera and Camellia sasanqua but also Eucalyptus polyanthemos and Euonymus japonicas. Given the broad host range and pathogenic nature, it is time to focus on management aspect to control the disease. [ABSTRACT FROM AUTHOR]

Background: Tea oil is widely used as edible oil in China, which extracted from the seeds of Camellia oleifera. In China, the national oil-tea camellia planting area reached 4.533 million hectares, the output of oil-tea camellia seed oil was 627 000 tons, and the total output value reached 18.3 billion dollars. Anthracnose is the common disease of Ca. oleifera, which affected the production and brought huge economic losses. Colletotrichum fructicola is the dominant pathogen causing anthracnose in Ca. oleifera. The retromer complex participates in the intracellular retrograde transport of cargos from the endosome to the trans-Golgi network in eukaryotes. Vacuolar protein sorting 35 is a core part of the retromer complex. This study aimed to investigate the role of CfVps35 in C. fructicola. Results: The CfVPS35 gene was deleted, resulting in reduced mycelial growth, conidiation, and response to cell wall stresses. Further analysis revealed that CfVps35 was required for C. fructicola virulence on tea oil leaves. In addition, the ΔCfvps35 mutant was defective in glycogen metabolism and turgor during appressorium development. Conclusion: This study illustrated that the crucial functions of CfVps35 in growth, development, and pathogenicity. [ABSTRACT FROM AUTHOR]

Camellia oleifera is an edible oil tree species native to China. Anthracnose is a common disease of Ca. oleifera, which reduces the production of the trees and brings huge economic losses. We have previously identified the fungus Colletotrichum fructicola as the major pathogen of anthracnose in Ca. oleifera. The retromer complex participates in the intracellular retrograde transport of the cargos from the endosome to the trans-Golgi network in the eukaryotes. Vacuolar protein sorting 29 is a subunit of the retromer complex. Targeted CfVPS29 gene deletion revealed that CfVps29 is involved in growth, conidiation, and the response to cell wall stress. We further found that the ΔCfvps29 mutant was minimally pathogenic to Ca. oleifera leaves, as a result of its defect in appressorium formation. This study illustrated the crucial functions of CfVps29 in the development, cell wall stress response, and pathogenicity of C. fructicola and, therefore, identified it as a potential fungicide target for the control of anthracnose. [ABSTRACT FROM AUTHOR]

Camellia seed oil, extracted from the seeds of Camellia oleifera Abel., is popular in South China because of its high nutritive value and unique flavor. Nowadays, the traditional extraction methods of hot pressing extraction (HPE) and solvent extraction (SE) are contentious due to low product quality and high environmental impact. Innovative methods such as supercritical fluid extraction (SCFE) and aqueous extraction (AE) are proposed to overcome the pitfalls of the traditional methods. However, they are often limited to the laboratory or pilot scale due to economic or technical bottlenecks. Optimization of extraction processes indicates the challenges in finding the optimal balance between the yield and quality of oils and phytochemicals, as well as the environmental and economic impacts. This article aims to explore recent advances and innovations related to the extraction of oils and phytochemicals from camellia seeds, and it focuses on the pretreatment and extraction processes, as well as their complex effects on nutritional and sensory qualities. We hope this review will help readers to better understand the trends, challenges, and innovations associated with the camellia industry. [ABSTRACT FROM AUTHOR]

In this study, we assessed 26 economic characteristics and yields of the mature fruit of 40 superior Camellia oleifera Abel plants grown at the C. oleifera germplasm resource nursery in the low-hot valley area of Southwest Zuizhou, China, using principal component analysis (PCA). Correlations among the characteristics and the variability of the plants in these characteristics were also analyzed. Out of the 26 characteristics, 16 primary economic characteristics were selected for comprehensive assessment, based on the results of which the plants were ordered to obtain excellent C. oleifera germplasms. The data were subjected to PCA, and the 16 characteristics were integrated into 6 independent comprehensive indices, which included PV1 (single-fruit weight), PV2 (pericarp thickness), PV3 (seed rate), PV4 (total unsaturated fatty acids), PV5 (iodine value) and PV6 (dry seed rate). Then, the sum of the products of the contribution rates of the components and components scores was taken as the comprehensive score of each superior plant. In C. oleifera grown in the low-hot valley area, the oil yield exhibited very significant positive correlations with the dry seed rate and kernel rate but a very significant negative correlation with the 100-seed weight. The dry seed rate exhibited very significant negative correlations with the fruit diameter and fresh seed rate. Among the 26 characteristics, the variations of the acid value, peroxide value, number of fertile seeds, 100-seed weight and single-fruit weight were great; those of the fruit diameter, fruit height, kernel yield, oleic acid and total unsaturated fatty acid were small, showing strong genetic stability. According to the obtained comprehensive scores, the top 10 plants were ordered as follows: CY-6 > CY-13 > CY-31 > CY-11 > CY-16 > CY-22 > CY-28 > CY-23 > CY-24 > CY-29. This result was basically consistent with the ranking result according to the average yield per unit crown width within five years. In the low-hot valley area of Guizhou, C. oleifera exhibits excellent performance in single-fruit weight, total unsaturated fatty acids and kernel rate, 6 characteristics, i.e., acid value, peroxide value, single-fruit weight, the number of fertile seeds, 100-seed weight and α-linolenic acid possess high breeding potentials. [ABSTRACT FROM AUTHOR]

The leaf serves as an important assimilation organ of plants, and the anatomical structure of leaves can reflect the adaptability of the plant to the environment to a certain extent. The current study aimed to cultivate superior local cultivars, and 35 healthy individual plants were selected from the Camellia oleifera germplasm resource nursery for a comparative study of the leaf structure. In July 2019, the leaves were collected from 35 selected healthy C. oleifera plants, and the leaf structure was observed by using the paraffin section method. Healthy individual plants were screened using variance analysis, correlation analysis and cluster analysis. The representative indices were selected according to the cluster membership, correlation indices and coefficient of variation (C/V) for a comprehensive evaluation of drought resistance via the membership function. There were extremely significant differences in 11 indices of leaf structure for these 35 healthy plants. C18 had the greatest leaf thickness, C7 the largest spongy tissue, and C38 the largest ratio of palisade tissue thickness to spongy tissue thickness (P/S). The clustering results of the healthy individual plants differed significantly. The membership function showed that the drought resistance of 35 C. oleifera plants was divided into five categories. C18 had very strong drought resistance, and C3, C7 and C40 had strong drought resistance. There were significant differences in terms of the upper epidermis, P/S ratio and spongy tissue among the C. oleifera plants. C18, C3, C7 and C40 exhibited satisfactory drought resistance. Although C39 and C26 had moderate drought resistance, their P/S ratios were high, which might be used to cultivate high-yield and drought-resistant C. oleifera varieties. The leaf P/S ratio of C. oleifera from low-hot valley areas was high. Among various leaf structures, spongy tissue, upper epidermis, P/S ratio and cuticle constitute the drought resistance evaluation indices for C. oleifera grown in low-hot valley areas. [ABSTRACT FROM AUTHOR]

Tea-oil tree (Camellia oleifera Abel.) is an important edible oil woody plant with a planting area over 3,800,000 hectares in southern China. Species of Diaporthe inhabit a wide range of plant hosts as plant pathogens, endophytes and saprobes. At present, relatively little is known about the taxonomy and genetic diversity of Diaporthe on C. oleifera. Here, we conducted an extensive field survey in Hunan Province in China to identify and characterise Diaporthe species associated with tea-oil leaf spots. As a result, eleven isolates of Diaporthe were obtained from symptomatic C. oleifera leaves. These isolates were studied by applying a polyphasic approach including morphological and phylogenetic analyses of partial ITS, cal, his3, tef1 and tub2 gene regions. Two new Diaporthe species (D. camelliae-oleiferae and D. hunanensis) were proposed and described herein, and C. oleifera was revealed to be new host records of D. hubeiensis and D. sojae. This study indicated there is a potential of more undiscovered Diaporthe species from C. oleifera in China. [ABSTRACT FROM AUTHOR]

Moringa oleifera (moringa) is an important fodder tree species. Although several researches study the effects of fertilization on moringa growth, the response of non-structural carbohydrate (NSC) to nitrogen (N) and phosphorus (P) fertilization in moringa seedlings is poorly understood. Here, we employed a pot experiment to investigate the effects of N and P fertilization on NSC dynamics in moringa seedlings in southern China. The results showed that the moringa root NSCs were 427 mg g−1 in the control treatment (over 50% of the total NSCs, 739.8 mg g−1), while the leaf NSCs only stored about 10% of NSCs in the individual tree. Compared to the control treatment, the NSCs in leaf, stem, and root of moringa seedlings were greatly reduced by N and P fertilization, which could be explained by the dilution effects of increased biomass following fertilization. However, the magnitude of NSC change with fertilization varied with tissue and N & P application levels. Our results suggest that there is a trade-off between structural carbohydrates (SCs) and NSCs among different organs in morniga seedlings. As moringa seedlings may have specific nutrient acquiring strategies that differs from their adult tree, long-term and large-scale researches should focus on the effects and underlying mechanisms of fertilization on the trade-off between SC and NSC in seedling and the adult tree of moringa in future. [ABSTRACT FROM AUTHOR]

Background: The oil-tea tree (Camellia oleifera Abel.) is a woody tree species that produces edible oil in the seed. C. oleifera oil has high nutritional value and is also an important raw material for medicine and cosmetics. In China, due to the uncertainty on maturity period and oil synthesis mechanism of many C. oleifera cultivars, growers may harvest fruits prematurely, which could not maximize fruit and oil yields. In this study, our objective was to explore the mechanism and differences of oil synthesis between two Camellia oleifera cultivars for a precise definition of the fruit ripening period and the selection of appropriate cultivars. Results: The results showed that 'Huashuo' had smaller fruits and seeds, lower dry seed weight and lower expression levels of fatty acid biosynthesis genes in July. We could not detect the presence of oil and oil bodies in 'Huashuo' seeds until August, and oil and oil bodies were detected in 'Huajin' seeds in July. Moreover, 'Huashuo' seeds were not completely blackened in October with up to 60.38% of water and approximately 37.98% of oil in seed kernels whose oil content was much lower than normal mature seed kernels. The oil bodies in seed endosperm cells of 'Huajin' were always higher than those of 'Huashuo' from July to October. Conclusion: Our results confirmed that C. oleifera 'Huashuo' fruits matured at a lower rate compared to 'Huajin' fruits and that 'Huajin' seeds entered the oil synthesis period earlier than 'Huashuo' seeds. Moreover, 'Huashuo' fruits did not mature during the Frost's Descent period (October 23–24 each year). [ABSTRACT FROM AUTHOR]

The tea-oil tree (Camellia oleifera Abel.) is a commercial edible-oil tree in China, and anthracnose commonly occurs in its plantations, causing great losses annually. We have previously revealed that CfSnf1 is essential for pathogenicity in Colletotrichum fructicola , the major pathogen of anthracnose on the tea-oil tree. Here, we identified CfGcn5 as the homolog of yeast histone acetyltransferase ScGcn5, which cooperates with ScSnf1 to modify histone H3 in Saccharomyces cerevisiae. Targeted gene deletion revealed that CfGcn5 is important in fungi growth, conidiation, and responses to environmental stresses. Pathogenicity assays indicated that CfGcn5 is essential for C. fructicola virulence both in unwounded and wounded tea-oil tree leaves. Further, we found that CfGcn5 is localized to the nucleus and this specific localization is dependent on both NLS region and HAT domain. Moreover, we provided evidence showing that the nuclear localization is essential but not sufficient for the full function of CfGcn5, and the NLS, HAT, and Bromo domains were proven to be important for normal CfGcn5 functions. Taken together, our studies not only illustrate the key functions of CfGcn5 in growth, development, and pathogenicity but also highlight the relationship between its locations with functions in C. fructicola. [ABSTRACT FROM AUTHOR]

Camellia oleifera Abel. is an economically important plant for edible oils. To investigate the importance of wild bee abundance at different canopy and spatial scale for fruit set of Camellia oleifera, we evaluated the relationship of bee abundance with fruit set using yellow pan trap, with additional focus on distance and wild bee abundance counts at a farm in China for 2 years. We found that yellow traps collected 95% more individual bees than the second‐best (pink) trap colour. Looking across canopy positions, the number of wild bees (including Colletes gigas, Andrena camellia, Andrena striata, Andrena hunanensis and Andrena chekiangensis) varied significantly in each year. The fruit set also varied significantly based on canopy position. In 2018, there was with an average fruit set of 34.13% in the lower canopy, 54.30% in the middle canopy and 47.41% in the upper canopy. In 2019, fruit set was 29.67% in the lower canopy, 54.15% in the middle canopy and 47.36% in the upper canopy. Comparing inter‐annual changes, only the fruit set and number of bees in the low canopy showed significant differences between 2018 and 2019. Fruit set and wild bee abundance were positively correlated in all canopy layers in each year, and there was an interactive effect between canopy and bee abundance on fruit set. Across 205 trees, growth indicators, crown size and tree height, increased significantly from 2018 to 2019, but the fruit set did not increase with the significant increase in the number of flowers. From the spatial perspective, wild bee abundance and fruit set were positively correlated, but fruit set was negatively correlated with distance from a large bee nesting aggregation nearby. Among the variables investigated, bee abundance seems to have the strongest influence on fruit set in C. oleifera. [ABSTRACT FROM AUTHOR]

Camellia oleifera Abel. (C. oleifera) as an important economic tree species in China has drawn growing attention because of its highly commercial, medic, cosmetic, and ornamental value. To deepen our understanding about the photosynthetic characters during the whole developmental stage as well as the molecular basis of photosynthesis, a comparative analysis of the leaf transcriptome of two C. oleifera cultivars, 'Guoyou No.13' (GY13) and 'Xianglin No.82' (XL82), with different photosynthetic characteristics from May to September has been conducted. In this study, a group of genes related to photosynthesis, hormone regulation, circadian clock and transcription factor, involved in the photosynthetic advantage. Photosynthetic parameters from May to September of these two cultivars provided evidence supporting photosynthetic advantage of GY13 compared to XL82. In addition, expression levels of 12 differentially expressed genes (DEGs) were validated using real-time PCR (RT-PCR). To screen gene clusters and hub genes that might directly regulated the photosynthetic differences between cultivars, a Weight Gene Co-expression Network Analysis (WGCNA) was conducted. Three co-expression network (module) and top ten connected genes (hub genes) were identified that might play crucial role in the regulatory network of photosynthesis. The results not only showed multiple functional genes that might involve in the differences of photosynthetic characteristics between cultivars, but also provide some evidences for the heat tolerance might be an important character which helps GY13 kept higher photosynthetic parameters than XL82 during the developmental stage. In summary, our transcriptomic approach together with RT-PCR tests allowed us to expand our understanding of the characters of C. oleifera cultivars with different photosynthetic efficiency during the developmental stage and to further exploring new candidate genes involve in high photosynthetic efficiency in molecular-assisted breeding program of C. oleifera. [ABSTRACT FROM AUTHOR]

This paper reports on an experimental investigation of the drying characteristics and kinetics of camellia oleifera seeds under microwave intermittent drying conditions. The effects of key parameters such as microwave power, heating time, and the length of the intermittent time are discussed in detail. The energy consumption in the drying process along with the main quality parameters of camellia oil, namely the peroxide and acid values, have also been determined and compared with hot‐air drying. Results show that the microwave drying curve consists of an acceleration rate period, a constant rate period and a falling rate period. As the microwave power and heating time increase, the drying time decreases. While as the length of the intermittent time increases, the drying time increases. The hot‐air drying time was found to be much longer than microwave drying time, and the energy consumed during hot‐air drying was also several hundred times higher than that used during microwave intermittent drying. The acid and peroxide values of camellia oil after hot‐air and microwave drying were both within the allowable range in the National Standard of China. The Midilli and Kucuk model was the best model to describe the kinetics of the drying process. Practical applications: Drying is the first step in the processing of camellia oleifera seeds, which not only affects the storage of camellia oleifera seeds, but also affects the quality of camellia oil, and has thus become a research hotspot in recent years. However, several disadvantages of hot‐air drying have been identified like the slowness of the drying process and the relatively large energy consumption. Therefore, finding a drying method that is more suitable is necessary. Microwave intermittent drying is a type of discontinuous drying. The moisture and temperature inside the material can be evenly redistributed during the intermittent time, so that the material is not overheated. This feature of preserving the quality of the products to be dried has made microwave intermittent drying attractive and has been successfully applied to agricultural, forestry, and food products. [ABSTRACT FROM AUTHOR]

Automation processing has become particularly important for the Camellia oleifera industry in Southern China, as the agricultural economy is ever increasing. Fruit shelling of Camellia oleifera is a very critical link in the production line. There are still some problems so far in the sorting and recognition system for the Camellia oleifera sheller, such as single-feature recognition method, great disturbance by target color, and relatively low adaptive function. This study aims to propose a multi-features intelligent sorting algorithm, combining the artificial immune network (aiNet) and Support Vector Machine (SVM), in order to fully utilize the multi-feature clustering feature of immune algorithm, and the dichotomy feature of SVM algorithm. Six morphological and color characteristics of shell kernel in a Camellia oleifera were extracted, including elongation, roundness, completeness, R component, G component, and B component of color feature. These characteristics were used to sort and identify the shell and kernel of Camellia oleifera. The collected images were first preprocessed, then three morphological features were integrated into the aiNet algorithm for multi-features comprehensive identification, finally three-color features were input into the SVM algorithm for the recognition of color features. Since the color of fruit shells and seeds varied in different storage periods, 3 and 12 days were selected to obtain the obvious color characteristics of Camellia oleifera fruits, considering the influence of temperature, and humidity, on the picking Camellia oleifera fruits. In the experimental test, the multi-features immune network combined with SVM algorithm significantly reduced the complexity of multi-dimensional operation while saved the operation time. The results showed that the sorting efficiency of Camellia oleifera fruit reached 97.4% in 3 days, and 76.6% in 12 days, indicating a high separation efficiency. The recognition time reached an average of 600 ms and a minimum of 510 ms, where the recognition time was the sum of the consumption time of two algorithms, and the ratio of time consumed by aiNet and SVM algorithm was 2.3:1. A comparation was made in the recognition rate and time, including the multi-dimensional aiNet, the multi-dimensional SVM algorithm, the color threshold method, and the morphological threshold method. Although the conventional algorithm of color morphological threshold had a short execution time, it does not have multi-features adaptability, as its simple structure. Nevertheless, the usage of multi-features immune algorithm can easily lead to the "dimension disaster" of long recognition time, particularly when to recognize six features of shape and color. The multi-dimensional SVM algorithm was not suitable for the multi-feature recognition, due to its binary structure. An improved algorithm can also lead to the problem of long sorting time, due to the complexity of structure. The recognition rate decreased, when the color difference was not obvious during the storage period of 12 days. The combination of artificial immune and SVM can be used to enhance the efficiency and real-time performance, particularly better than other methods in the shelling and sorting production line of Camellia oleifera fruit. The finding can verify the algorithm with innovative and practical characteristics, thereby to improve the production of Camellia oleifera fruit. [ABSTRACT FROM AUTHOR]

Endophytic bacteria, which are common in plant tissues, may help to control plant pathogens and enhance plant growth. Camellia oleifera, an oil-producing plant, is widely grown in warm, subtropical, hilly regions in China. However, C. oleifera is strongly negatively affected by C. oleifera anthracnose, which is caused by Colletetrichum fructicola. To find a suitable biocontrol agent for C. oleifera anthracnose, 41 endophytes were isolated from the stems, leaves, and roots of C. oleifera. Bacterial cultures were identified based on analyses of 16S rDNA sequences; most strains belonged to the genus Bacillus. The antagonistic effects of these strains on C. fructicola were tested in vitro. In total, 16 strains inhibited C. fructicola growth, with B. subtilis strain 1-L-29 being the most efficient. Strain 1-L-29 demonstrated antagonistic activity against C. siamense, C. asianum, Fusarium proliferatum, Agaricodochium camellia, and Pseudomonas syringae. In addition, this strain produced indole acetic acid, solubilized phosphate, grew on N-free media, and produced siderophores. To facilitate further microecological studies of this strain, a rifampicin-resistant, green fluorescent protein (GFP)-labeled strain, 1-L-29gfpr, was created using protoplast transformation. This plasmid had good segregational stability. Strain 1-L-29gfpr was re-introduced into C. oleifera and successfully colonized root, stem, and leaf tissues. This strain remained at a stable concentration in the root more than 20 d after inoculation. Fluorescence microscopic analysis showed that strain 1-L-29gfpr thoroughly colonized the root surfaces of C. fructicola as well as the root vascular tissues of Arabidopsis thaliana. [ABSTRACT FROM AUTHOR]

Camellia oleifera seed, commonly known as the oil-seed camellia seed or oil-tea camellia seed, just like oil palm, olive and coconut, is one of the most prominent woody edible oilseeds. Camellia oleifera seed oil, one of the favorite cooking oil used wildly in China’s southern provinces and Southeast Asia, has much in common with olive oil in chemical composition drawing great attention from the public, with high amounts of oleic acids (76.1%-83.3%) and linoleic acid (7.0%-11.03%) and was often titled as “Eastern Olive Oil”. However, it is not easy to store the seeds because of the high total amount of unsaturated fatty acids up to 90% and high temperature and high humidity climate in Camellia oleifera seed producing area, which are tend to lead to the quality degradation during storage. In order to maintain good storage quality, the effects of storage conditions on quality of Camellia oleifera seeds and the reasons for them were explored in this study. Using moisture content of material (7%, 8.5%, 10%, 11.5%, 13%), air relative humidity (50%, 60%, 70, 80%) and storage temperature (4, 15, 20, 25℃) as single factors, the change in oil content, acid value and peroxide value of Camellia oleifera seeds were determined during the 8-months storage. At the same time, the lipase activity, lipoxygenase activity and the growth of microorganisms, which were highly related to the increases of acid value and peroxide value, were also investigated during storage. The change trend of oil content showed an increase in the beginning and decreased after the peak, indicating that there was a phenomenon of post-ripening observed during the storage. In this study, the post-ripening period of stored Camellia oleifera seeds was 3-4 months, which was similar to the post-ripening period of 2-3 months for peanut and was obviously longer than the post-ripening period of 10-20 days for corn. The acid value and peroxide value were increased with the increase of moisture content of material, storage temperature and storage time. The significantly positive correlation between the lipase activity and the acid value indicated that the increase for acid value of Camellia oleifera seeds during storage was mainly due to the accumulation of free fatty acids produced by hydrolysis of fat resulting from lipase. Within 6-months storage, only a few of molds of Camellia oleifera seeds were observed. However, once microorganisms grew in large quantities with the prolongation of storage time, lipase would be produced to further promote the increase of acid value. In addition, based on the above results, the effects of moisture content of material, air relative humidity, storage temperature and storage time on oil content, acid value and peroxide value were investigated using response surface method. The regression equation predicting quality variation was established and it proposed that suitable air relative humidity and storage temperature can promote the post-ripening of Camellia oleifera seeds during storage. The comprehensive optimization ranges of Camellia oleifera seed storage parameters, obtained using frequency analysis method from the regression analysis of standardized comprehensive score values, were as follows: air relative humidity of 57.6%-67.4%, temperature of 17.2℃-20.4℃, moisture content of 8.9%-10.4%, storage time of 62.2d-110.3d. Under the optimal conditions, the comprehensive qualities of Camellia oleifera seed oil are good. In order to make the best of post-ripening effect and improve the storage quality, it is suggested that in practical operation, air relative humidity of the storage during post-ripening period should be 1%-2% higher than the storage after the post-ripening stage, and the temperature should be 1℃-2℃ higher. This study can provide support for storage and the subsequent oil processing of Camellia oleifera seeds to improve the oil production rate and guarantee the quality. [ABSTRACT FROM AUTHOR]

Camellia oleifera fruit shell (CFS), a waste lignocellulosic biomass resulting from Camellia oleifera oil production industry, is abundantly available in Southern China. Herein, to understand the structural variations of CFS lignins and lignin-carbohydrate complexes (LCC) during ripening, the native lignin and LCC fractions from CFS (harvested every seven days from October 1 to 30, 2022) were isolated and characterized systematically. The molecular weights of both MWL and DEL fractions steadily increased during ripening. CFS lignins contained abundance of β-O -4′ linkages (maximum of 58.6 per 100Ar in DEL-2), and had low S/G ratios (S/G < 0.6). Moreover, the amounts of β-O -4′ linkages in MWL, DEL, and LCC-AcOH fractions increased first and then decreased during ripening. The main lignin-carbohydrate linkages in the LCC-AcOH fractions were benzyl-ether (7.0–9.4 per 100Ar) and phenyl-glycoside (4.5–5.2 per 100Ar) bonds. Based on the quantitative results, the potential structural diagrams of lignins from different ripening stages of CFS were proposed. Additionally, the LCC-AcOH fractions exhibited pronounced antioxidant capacity and were promising as natural antioxidants. The properties and functions of lignin in plant cell walls, as well as its further appreciation, are crucial for the design and selection of feasible pretreatment strategies for the lignocellulosic materials. [Display omitted] • Native lignin and LCC from Camellia oleifera fruit shells (CFS) were characterized. • The lignin macromolecules polymerized gradually with CFS development. • CFS lignin had abundance of β-O -4′ linkages (up to 58.6 per 100Ar). • Potential lignin diagrams of CFS with different ripening stages were proposed. • LCC-AcOH fractions exhibited pronounced antioxidant capacity. [ABSTRACT FROM AUTHOR]

The domestic wastewater collection and treatment rate of Nairobi, Kenya are not high. The wastewater in the Kibera slum on the outskirts of the city that is directly discharged to the environment and pollution of the surrounding water body is a serious problem. This paper takes the domestic wastewater in the slum area as the research objective and researches on the wastewater characteristics, collection, and treatment, therefore providing the reference for the wastewater collection and treatment technology in the region. In this paper, domestic wastewater in the Kibera slum of Nairobi was sampled and investigated to find out the characteristics of wastewater discharged, the way of discharge of the household wastewater, and the management in this area. The study shows that there are differences in the concentration of main pollutants such as nutrients and organic matter in the wastewater from the household discharged to the residential river in the slum area. The domestic wastewater in this slum area contained a high concentration of nutrients such as nitrogen and phosphorus and other organics, total suspended solids (TSS), total coliforms and color, and with no treatment methods. Therefore, economic and feasible treatment technology needs to be developed. A pilot study was conducted on the treatment of domestic wastewater in the slum area by combining the seed extract of the natural plant Moringa oleifera as a coagulant and vertical flow constructed wetland (VFCW) at Tongji University, Shanghai, China. The VFCW system was efficient in chemical oxygen demand (COD), TSS, turbidity, total phosphorus (TP), and phosphates (PO 4 -P) removal, but the removal efficiency of nitrogen (total nitrogen (TN), ammonium nitrogen (NH 4 -N), and nitrate (NO 3 -N)) was poor, and the effluent pH reached the required discharge country's standard of the water. The average removal efficiencies for COD (79.99%), TSS (86.84%), turbidity (87.35%), TP (61.29%), PO 4 -P (65.66%), TN (14.11%), NH 4 -N (18.17%), and NO 3 -N (93%) were achieved by the treatment system. Furthermore, the removal efficiencies of pollutants such as TP, PO 4 -P, TN, and NH 4 -N were carried out by using the fruit extract of Moringa oleifera as raw material and zeolite as an auxiliary agent. The comprehensive effect of zeolite combined with VFCW and natural coagulant in the treatment of domestic wastewater was investigated. The COD removal efficiency was increased by (9%). TN by (46%), NH 4 -N by (67%), TP by (19%), and turbidity improved by (9%). In short, the domestic wastewater in the Kibera slum was collected and pretreated with natural plant coagulant, and then purified by vertical flow constructed wetland, which can not only significantly reduce the pollutant concentration but also basically meet the discharge standards. It is a low-cost sewage treatment technology suitable for poor areas., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Tea oil camellia (Camellia oleifera) is an important woody oil tree in southern China. However, little is known regarding the molecular mechanisms that contribute to high oleic acid accumulation in tea oil camellia. Herein, we measured the oil content and fatty acid compositions of high- and low-oil tea oil camellia seeds and investigated the global gene expression profiles by RNA-seq. The results showed that at the early, second and third seed developmental stages, a total of 64, 253, and 124 genes, respectively, were significantly differentially expressed between the high- and low-oil cultivars. Gene ontology (GO) enrichment analysis of the identified differentially expressed transcription factors (TFs; ABI3, FUS3, LEC1, WRI1, TTG2 and DOF4.6) revealed some critical GO terms associated with oil biosynthesis and fatty acid accumulation, including glycolysis, zinc ion binding, positive regulation of fatty acid biosynthetic process, triglyceride biosynthetic process, seed coat development, abscisic acid-mediated signaling pathway and embryo development. Comprehensive comparisons of transcriptomic profiles and expression analysis of multigenes based on qRT-PCR showed that coordinated high expression of the upstream genes HAD, EAR and KASI directly increased the relative levels of C16:0-ACP, which provided enough precursor resources for oleic acid biosynthesis. Continuous high expression of the SAD gene accelerated oleic acid synthesis and accumulation, and coordinated low expression of the downstream genes FAD2, FAD3, FAD7, FAD8 and FAE1 decreased the consumption of oleic acid for conversion. The coordinated regulation of these multigenes ensures the high accumulation of oleic acid in the seeds of tea oil camellia. Our data represent a comprehensive transcriptomic study of high- and low-oil tea oil camellia, not only increasing the number of sequences associated with lipid biosynthesis and fatty acid accumulation in public resource databases but also providing a scientific basis for genetic improvement of the oleic acid content in woody oil trees. [ABSTRACT FROM AUTHOR]

Camellia spp., which are self-incompatible plants, are some of the most important woody species producing edible oil in Southeast Asian countries. However, the demand for camellia oil currently exceeds the supply due to low product yields that have resulted from a decrease in pollination services. Although Camellia osmantha, C. vietnamensis, and C. oleifera are cultivated in South China, little is known about the correspondence between pollinator abundance and pollinator services for this plant genus. In this study, the diversity, daily activity patterns, and pollination effectiveness of insects visiting C. osmantha, C. vietnamensis and C. oleifera were investigated. A total of 24 species, belonging to four orders and 11 families, of visiting insects were identified. Apis cerana cerana Fabricius, Vespa bicolor Fabricius, V. velutina Lepeletier, V. ducalis Smith, and Phytomia zonata Fabricius were the dominant pollinators. The daily activity peaks of the five visiting insects were between 10:00 and 14:00, which may have been related to the pattern of floral resource production (particularly nectar). Cross-pollination by insects significantly increased the fruit production rates of C. osmantha, C. vietnamensis, and C. oleifera. Therefore, the wild bees and flies that pollinate wild and cultivated Camellia plants should be protected in South China. [ABSTRACT FROM AUTHOR]