Podocarpus macrophyllus is a common garden ornamental and greening tree species in southern China, with high economic and medicinal value. To study the physiological response of nitrogen addition under different phosphorus environments to P. macrophyllus seedlings, two-year-old P. macrophyllus seedlings were used as the material, two soil phosphorus conditions including low additional phosphorous (0.26 g/plant), high phosphorus addition (1.08 g/plant), three nitrogen addition levels including low nitrogen addition (0.53 g/plant), medium nitrogen addition (1.06 g/plant) and high nitrogen addition (2.12 g/plant) were set up and analyzed the differences of physiological characteristics, chlorophyll content, gas exchange parameters and leaf nutrient content of P. macrophyllus seedlings in each treatment group. Nitrogen addition increased the activity of POD, and high concentration nitrogen fertilizer decreased the activity of SOD. The application of nitrogen fertilizer in a low phosphorus environment increased soluble sugars and soluble proteins, decreased MDA and Pro. Soluble protein and soluble sugar accumulation decreased in high nitrogen and phosphorus environment, but MDA and Pro increased. The chlorophyll content of P. macrophyllus seedlings was the highest under medium concentration nitrogen treatment. The addition of nitrogen in low phosphorus environment increased the P_n, T_r and G_s of P. macrophyllus seedlings, while C_i (intercellular CO₂ concentration) of P. macrophyllus seedlings decreased. The P_n, T_r and G_s were the highest and C_i was the lowest in the medium nitrogen treatment group in high phosphorus environment. P_n, T_r and G_s decreased, and the C_i increased in the high nitrogen concentration and high phosphorus environment. The same change trend of P_n and T_r and correlation analysis showed that P_n of P. macrophyllus seedlings was mainly limited by stoma factors. Nitrogen addition promoted the increase of leaf nitrogen content in low phosphorus environment, but decreased the leaf nitrogen content in high phosphorus environment. Nitrogen addition limited the accumulation of phosphorus in the leaves of P. macrophyllus seedlings, but the increase of soil phosphorus content promoted the accumulation of phosphorus content in leaves. The increase of phosphorus fertilizer concentration increased the enzyme activity of P. macrophyllus seedlings under different nitrogen treatments. The increase of nitrogen fertilizer concentration decreased the content of MDA and Pro, and the content of soluble sugar and soluble protein increased in the low nitrogen and high nitrogen treatment groups. The increase of phosphorus fertilizer concentration increased the content of MDA and Pro, and the content of soluble sugar and soluble protein decreased in the high nitrogen treatment groups. Increasing the concentration of phosphate fertilizer promoted the chlorophyll content and photosynthetic efficiency of low and medium nitrogen treatment groups, while increasing the concentration of phosphate fertilizer decreased the chlorophyll and photosynthetic efficiency.

In order to analyze the effects of different intercropping patterns on the growth status, yield and quality of G. rigescens, six plant materials including Camellia sinensis (L.), Juglans regia L, Glycine max, Coix lacryma-jobi L., Glycine max (L.) merr and Vicia faba L. were selected to form seven crops patterns of G. rigescens monoculture and intercropping. Plant height, plant width, leaf length, leaf width and stem diameter of G. rigescens in vigorous growth period and harvest period were detected, fiber root number, root length, root diameter, gentiopicroside content were determined to explore the effects of different intercropping patterns on the yield and quality of G. rigescens. The results showed that the growth state of above ground part of G. rigescens intercropped with Juglans regia L. and Camellia sinensis (L.) was better than that of G. rigescens intercropped with Glycine max, Coix lacryma-jobi L., Glycine max (L.) merr and Vicia faba L. The intercropping with Juglans regia L. significantly promoted the growth of plant height of G. rigescens, while the intercropping with Camellia sinensis (L.) had large plant width, high leaf expansion and strong plants. The yield of G. rigescens in different intercropping cultivation was: Camellia sinensis (L.)>Juglans regia L.>Glycine max>Glycine max (L.) merr>control>Vicia faba L.>Coix lacryma-jobi L.. The yield of G. rigescens in intercropping with tea was the highest, 142.4 kg per hectare, 46.87% higher than that in the control. In different intercropping patterns, the number of fibrous roots of G. rigescens intercropping with Camellia sinensis (L.) was the highest, about 6-9 fibrous roots per plant, which was significantly higher than that of the control. The determination of gentiopicroside content in G. rigescens under different intercropping modes showed that: Camellia sinensis (L.) intercropping >Juglans regia L. intercropping>Vicia faba L. intercropping>Glycine max (L.) merr intercropping>Glycine max intercropping>control (monoculture)>Coix lacryma-jobi L. intercropping>Pharmacopoeia (1.5%), the gentiopicroside content in the roots and stems of Camellia sinensis (L.) intercropping was the highest, which was 3.36%±0.07%, significantly higher than that of the control and Coix lacryma-jobi L. intercropping intercropping. The correlation analysis showed that the root quality and yield of G. rigescens had a significant positive correlation with the aboveground plant width and leaf length, but had no significant correlation with the plant height of G. rigescens. The comprehensive score of the roots and stems by the membership function showed that the comprehensive quality of G. rigescens was better than that of the control: Camellia sinensis (L.) intercropping>Juglans regia L. intercropping>Vicia faba L. intercropping>Glycine max intercropping>Glycine max (L.) merr intercropping>control (monoculture)>Coix lacryma-jobi L. intercropping, Camellia sinensis (L.) intercropping, Juglans regia L intercropping, Vicia faba L. intercropping, Glycine max intercropping, Glycine max (L.) merr intercropping all higher than control, and the comprehensive score of intercropping Camellia sinensis (L.) was the highest, reaching 0.99.

The global quality cigar tobacco planting areas are basically dominated by tropical rain forest or tropical monsoon climate. The overall quality of cigar raw materials from Chinese and overseas planting areas has the certain disparity by multiple factors. In order to study the chemical constituents, a cluster and comparative analysis was conducted on some domestic and foreign cigar tobacco. The contents of carbohydrates and the distribution of amino acids reflected the characteristics of cigar tobacco. There were large differences among cigar tobacco samples from different planting areas in the content of conventional chemical components, and the chemical components of the cigar tobacco leaves had harmonious percentage in general. The average contents of total sugar, reducing sugar, anatabine, glutamic acid, linolenic acid and linoleic acid in cigar tobacco samples from Hainan and foreign planting areas were significantly lower than those in the other three planting areas in China, but the pectin content showed the opposite pattern. In terms of aroma components, the average contents of carotenoid degradation products such as megastigmatrienone, linalool and damascenone, non-enzymatic brown-reaction products such as pyrazine and furfural, and solanone in cigar tobacco samples from other three planting areas in China were significantly higher than those from Hainan and foreign planting areas. The average contents of neophytadiene, isoamyl alcohol, pyridine, phenyl ethanol and other aroma components in cigar tobacco samples from all domestic planting areas were higher than those from foreign planting areas, and the difference was significant or most significant. These planting areas fell into four categories according to clustering results. The first group included America areas and Hainan Province in China. The second group included Indonesian areas. Hubei Province, Yunnan Province was in the third group, and Sichuan province was in the fourth group.

Citrus reticulata cv. chachiensis, also known as Xinhui Mandarin Orange, has a long history of cultivation in Guangdong (Xinhui) and is a local agricultural product in Guangdong. There are no relevant studies on the symptoms description and distribution of Candidatus Liberibacter asiaticus (CLas) in C. reticulata cv. chachiensis infected with Citrus Huanglongbing (HLB). Through this study, it can provide a basis for the study of the movement of CLas in citrus plant branches and fruit pith and can also provide ideal plant materials for the subsequent acquisition of high concentration of CLas. In this study, C. reticulata cv. chachiensis branches and fruit pith infected with CLas were used as plant material to identify symptoms and analyze the distribution of CLas in different parts of citrus branches and different length fragments of the fruit pith based on real-time quantitative PCR (qPCR). Through the observation of the leaves and fruits from the infected citrus plants, the upper leaves of the branches infected with CLas showed mottled and element-deficient yellowing, especially the symptoms of the new leaves of the branches were more obvious, while the color of the lower old leaves was dark green and the texture was hard. Compared with the healthy fruit, the fruit infected with CLas showed uneven coloring, showing typical symptoms of "red nose fruit". Meanwhile, compared with the healthy fruit, the fruit infected with CLas showed uneven size, abnormal body and asymmetrical shape, the seed was small and the seed aborted. The concentration of CLas in the central axis of the fruit was close to that in the fruit pith, and significantly higher than that in other parts of the branches (P<0.05). CLas was also unevenly distributed in different length segments of the same fruit pith, and the concentration of CLas was the highest in the middle of fruit pith (1-3 cm fragment), the concentration of CLas in the central axis and fruit pith of HLB-infected C. reticulata cv. chachiensis fruits is significantly higher than that of other parts. The study could be a reference for the identification of HLB, a basis for the study of the movement of CLas in citrus plant branches and fruit pith, and used to select ideal plant materials for the subsequent acquisition of high concentration of CLas.

Neonicotinoids (NEOs) contain imidacloprid (IMI) and acetamiprid (ACE), which are widely used in the world. In this study, earthworms (Eisenia foetida) were used as soil animal. Through high-throughput sequencing and measurement of soil physical and chemical properties, the changes of bacterial communities between IMI and ACE contaminated red soil (BCK, DCK) and soil after earthworm introduction (B, D), and the relationship with environmental factors were analyzed to explore the animal remediation mechanism of contaminated red soil. The introduction of IMI and ACE reduced the diversity of microbial population, significantly changed the composition of soil bacterial community structure, and decreased the content of soil organic matter (SOM) and total nitrogen (TN), compared with the natural red soil (CK). The addition of earthworms increased the relative abundance of Actinobacteriota, Proteobacteria and Bacteroidota, which have the ability of insecticide resistance and degrading. pH value, TN, total phosphorus (TP) and total potassium (TK) contents of contaminated soil increased. Combined with the correlation analysis of soil physiochemical properties, it was found that pH, TN, TK and SOM had a great influence on the bacterial community structure among the treatment groups at the genus level. The study showed that IMI and ACE pollution reduced the contents of SOM and soil TN, and destructed the original bacterial community structure in the soil. Earthworm activity improved soil fertility of contaminated red soil, alleviated the adverse effects of IMI and ACE on soil microbial flora, restored and enriched the diversity of microbial species in NEOs-contaminated soil to a certain extent, and then accelerated the degradation of NEOs in soil. This study showed the feasibility to screen the efficiently IMI and ACE-degrading bacteria from drilosphere, and would provide theoretical basis for the earthworm remediation of IMI and ACE-contaminated soil.

In order to determine the optimal conditions for the preparation of jackfruit starch-coconut oil complexes by Rapid Visco Analyzer (RVA), the influence of addition of coconut oil, complexation time and complexation temperature on the complexation index of jackfruit starch-coconut oil complexes was studied. The Box-Benhnken response surface method was used to optimize the process conditions for the preparation of jackfruit starch-coconut oil complexes. The optimal preparation parameters of the jackfruit starch-coconut oil complexes were 4% of the addition of coconut oil, 2.40 min of complexation time, 90.70 ℃ of complexation temperature, respectively. Under the optimal condition, the experimental value of complex index was 24.33%, which was in good agreement with the value predicted by the model (24.64%). The gelatinization temperature, peak viscosity, and though viscosity of jackfruit starch-coconut oil complexes were higher than those of the raw starch, while the final viscosity and setback value were lower than those of the raw starch. This indicated the thermal stability of the complex was improved. The swelling ability of the starch was restricted when the jackfruit starch-coconut oil complexes was formed, resulting in the lower swelling power and a lower solubility than those of the raw starch.

Cymbidium sinensis is a typical fragrant orchid variety with high economic and ornamental value. HS-SPME/GC-MS was used to analyze the volatile components of different flower organs in C. sinensis. Seven categories and 54 volatile components were detected, mainly composed of 21 aldehydes, 12 alcohols, 10 ketones, 5 benzenes, 2 furans, 2 acids and 2 terpenoids. There were 48 compounds presented in four different flower organs, including petals, sepals, labellums, and pistil columns, including 19 aldehydes, 10 alcohols, 9 ketones, 5 benzenes, 2 terpenoids, 2 furans and caproic acid. There were three components in petals, sepals and pistil columns, only two components were detected in sepals, and Acrolein was only detected in pistil columns. The results showed that there were significant differences in the volatile matter and content in different floral organs of flowers. A total of 49 volatile substances were detected in sepals, with the highest content reaching 99 106.15 μg/L, accounting for 35.88% of the total volatile organic compounds. Among which the highest content was cyclopentyl formaldehyde, which had the camphor flavor of mint. 51 volatile compounds were detected in the petals, with a substance content of 56 571.48 μg/L, accounting for 20.48% of the total volatile organic compounds, with the highest content being 1-penten-3-ol, which had a fruity aroma. A total of 48 volatile substances were detected in the labellum flap, with the lowest substance content of 41 645.32 μg/L, the proportion of total volatile organic compounds was 15.08%, among which the highest content of volatile substance was cyclopentyl formaldehyde. A total of 51 volatile compounds were detected in the pistil column, with a content of 78 868.68 μg/L, accounting for 28.56% of the total volatile organic compounds, with the highest content being hexanal, which presented a fresh oil, green grass, and apple aroma. Through principal component analysis, it was found that among the four flower organs, there was little difference between the lip and petal, while the pistil column had a greater difference from other organs, and the sepals also had a greater difference from other organs. Glutaraldehyde, hexanal, E-2-pentenal, E-2-hexenal, cyclopentyl formaldehyde, E-2-heptaneal, 1-penten-3-ol, E-2-penten-1-ol were the main volatile components released by floral organs. During the peak flowering period, the sepals of the flowers were the main floral organs that released volatile components, and there were significant differences in the content of floral aroma components among different floral organs.

In order to explore the polymeric 2-(2-phenylethyl) chromones (PPECs) components and the structures from agarwood (Aquilaria spp.), ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass/mass spectrometry (UPLC-Q-TOF-MS) was used to acquire the spectrum of TOF-MS and TOF-MS/MS of agarwood samples. The fragmentation pathway of PPECs was analyzed. The screening and structure confirmation of PPECs from agarwood was performed. A total of 55 PPECs components were identified. According to the structural characteristics, 55 components were grouped into three types, including dimeric 2-(2-phenylethyl) chromones (DPECs), trimeric 2-(2-phenylethyl) chromones (TPECs) and sesquiterpenoid-2-(2-phenylethyl) chromones (SPECs). All identified components were consisted of 44 DPECs, 3 TPECs and 8 SPECs, of which nine DPECs, one TPECs and one SPECs were firstly identified in agarwood. Furthermore, 2-4 isomers were observed for some PPECs components from agarwood. The results showed that agarwood were rich in PPECs components and the corresponding isomers. Meanwhile, the proportion of DPECs was the highest (80%) among total PPECs. The results could provide reference for the study of material basis of pharmacodynamics effect and utilization of agarwod.

Dioscorea esculenta (Lour.) brukill is a traditional miscellaneous grain in Hainan, and it is rich in polysaccharides. This study investigated the extraction process and anti-oxidant activity of the polysaccharides from D. esculenta by using the D. esculenta tuber powder as the raw material. The hot water extraction was used to optimize the extraction process of polysaccharides from D. esculenta by single factor experiments and three-factor and three-level L₉(3³) orthogonal tests. The crude polysaccharides from D. esculenta were purified by the Sveag method, dialysis, DEAE-52 cellulose column and SephadexG-100 gel column chromatography. The anti-oxidant activity of polysaccharide from D. esculenta was detected by DPPH method, hydroxyl radical method, superoxide anion method and reduction method. The optimal extraction method of the hot water extraction included temperature 70 ℃, solid-liquid ratio 1∶15, and extraction time 3 h. The polysaccharides extraction rate of D. esculenta was 1.94%. After multipleseparation and purification, neutral polysaccharides with uniform purity were obtained. The expriments of anti-oxidant activity of polysaccharides from D. esculenta showed that the DPPH radical scavenging capacity of polysaccharide from D. esculenta was weak. The polysaccharide from D. esculenta and scavenging rate of 1-5 mg/mL was maintained at about 10%, and with the increase of polysaccharide concentration, the scavenging capacity gradually decreased. The hydroxyl radical activity increased with the increase of polysaccharide concentration, and the scavenging rate reached 34.74% at 5 mg/mL. The superoxide anion free radical activity decreased gradually with the increase of polysaccharide concentration, and the scavenging rate reached 67.35% at 1 mg/mL. The reduction capacity of polysaccharides was weak, and the reduction capacity of 1-5 mg/mL remained 0.17. In this study, the extraction process of polysaccharides from D. esculenta was optimized, and it had certain antioxidant activity. It would lay the foundation for the functional product development and the mechanism research of drug function of D. esculenta.

Using the in vitro axillary bud of Anthurium (Anthurium andraeanum Lind.) as the materials, this article reports the influence of the droplet vitrification on Anthurium after cryopreservation, and plants regenerated tissues genetic stability were assessment. The results showed the highest survival rate of Anthurium (63.70%) was achieved after preculture for 4 days on MS solid medium containing 0.4 mmol/L sucrose and 2 mmol/L glycerol, dehydration with 80%PVS₂ at 0 ℃ for 50 min, cooling in droplets of PVS₂ placed on aluminum foil strips, after immersing in liquid nitrogen for 2 s, directly transferred it to a cryotube filled with liquid nitrogen, and kept it in liquid nitrogen for at least 30 min after rewarming them with MS liquid medium containing 1.2 mmol/L sucrose at room temperature for 20 minutes, transferred to recovery medium. Through ISSR and SSR molecular marker detection, the genetic stability of regenerated plants did not changed. The results would provide an effective way for long-term preservation of Anthurium andraeanum germplasm resources.