To understand the morphological diversity and degree of variation in lotus fruits from various sources, 81 dried mature lotus fruits were collected from different locations (including 59 wild populations, 15 cultivated populations, and 7 lotus cultivars) for morphometric measurements and systematic clustering analysis. There was substantial morphological variation among 81 accessions of lotus fruits. The longitudinal diameter ranged from 12.03 mm to 19.58 mm, the transverse diameter varied from 7.93 mm to 15.72 mm, the aspect ratio spanned from 1.01 to 1.97, and single grain weight fluctuated from 0.41 mm to 2.26 g. The morphology of lotus fruits from different sources was different. The average longitudinal diameter, transverse diameter, longitudinal/transverse diameter ratio, and grain weight of American lotus fruits was 13.97 mm, 11.98 mm, 1.17 and 1.13 g, respectively. For wild Asian lotus fruits, the values was 16.52 mm, 10.51 mm, 1.58 and 0.98 g, respectively. For the 15 cultivated Asian lotus populations, the average values was 15.81 mm, 11.18 mm, 1.42 and 1.07 g, respectively. For the 7 fruit lotus varieties, the average values was 16.71 mm, 13.20 mm, 1.27 and 1.53 g, respectively. The correlation analysis showed that the single fruit weight of lotus fruit was positively correlated with the longitudinal diameter and transverse diameter (P<0.05), and negatively correlated with the ratio of transverse diameter (P<0.05), but there were differences among different population sources. There was no significant correlation between longitude and latitude and morphological indexes of lotus fruits. The longitude was positively correlated with the ratio of longitudinal diameter and longitudinal diameter (P<0.01), but negatively correlated with transverse diameter and single grain weight (P<0.01). There was a significant positive correlation between latitude and longitudinal diameter (P<0.05), a very significantly positive correlation between latitude and longitudinal diameter ratio (P<0.01), a significantly negative correlation between latitude and transverse diameter (P<0.05), and a negative correlation between latitude and single grain weight (P<0.05). Systematic cluster analysis showed that 59 populations of wild lotus fruits could be divided into 2-5 branches. All lotus fruits of American lotus and the Chiang Mai population of Thai lotus formed the first cluster, and the remaining Asian lotus formed the second cluster. Morphological traits of lotus fruits varied across the different years of collection. The results would provide scientific basis for lotus resource conservation, auxiliary identification, germplasm innovation and lotus fruit production.

Drought resistant microbial preparations are beneficial soil microorganisms that produce plant growth hormone to enhance the drought tolerance of plants and promote plant growth, which is an ideal substitute for traditional chemical drought resistant preparations. In this study, the bacteria obtained in the soils of Wuyishan tea plantation were used as the research object to screen strains with the high secretion indole-3-acetic acid (IAA) ability and strong drought resistance, and the culture conditions optimization and whole genome sequencing analysis were also conducted. A strain SZF7 with high secreting IAA was obtained, which belonged to Bacillus cereus, which had stronger drought resistance than other strains. The optimal culture conditions for IAA secretion of SZF7 were pH 5.0 and 37 ℃ with 24 h incubation, and pH and temperature significantly affected on the IAA secretion. In the COG and KEGG metabolic pathways of SZF7 genome, the genes related to biological metabolism accounted for 47.96% and 68.52% of the total functional genes, respectively. The genes related to plant growth promotion included IAA, siderophore, non-ribosomal peptide synthase (NRPS), lipopeptide compounds and bacillibactin. There were two IAA synthesis pathways in SZF7, one of which was indole-3-pyruvate pathway mediated by indole-3-pyruvate decarboxylase, and the other was tryptamine pathway mediated by indole-3-glycerol phosphate synthase. This study would provide a scientific basis for the application of drought-resistant and growth-promoting bacteria in the production of tea and other cash crops.

Salt is a main factor limiting the utilization of saline land in coastal beach. Rice is the preferred food crop for the utilization of salinized land, and some rhizosphere microorganisms can improve the salt resistance of rice. In order to screen suitable rice varieties planted in salinized land, different rice varieties were selected to cultivate under NaCl stress during the whole growth period, and the diversity and structure of bacterial communities in rhizosphere soil were measured and analyzed by Illumina Miseq sequencing technology. The bacterial community diversity in the rhizosphere soil, the species richness of varieties B3 and B6 were significant higher than those of variety B1 in 0.6% NaCl treatments. The community structure, the dominant bacterial phyla were Chloroflexi, Proteobacteria and Actinobacteria with relative abundance more than 10% of three varieties under different concentrations of NaCl treatments. There were differences in the bacterial community structure of rhizosphere soil, and the number and types of enriched species were also different in different rice varieties. Variety B6 enriched fourteen bacterial taxa branches under 0.6% NaCl treatments, such as Acidobacteriae, Nostocaceae Vicinamibacterales, Thermomicrobiales, KD4-96, etc. Therefore, B6 planted in salinized land of coastal mudflat is beneficial to the formation of dominant bacterial community in rhizosphere soil.

The study was aimed to investigate the soil-microbial carbon, nitrogen and phosphorus characteristics of Eucalyptus plantations at different altitude gradients in Hainan Tropical Rainforest National Park. Typical Eucalyptus plantation forests at different altitudes (500 m, 700 m and 900 m) in Wuzhishan were used as the study object, and natural secondary forests at the same altitude were used as the control. Soil organic carbon (SOC) and total nitrogen (TN) content showed a gradual increase with elevation, and total phosphorus (TP) showed a gradual decrease. The range of variation was 13.16-13.58, 0.93-1.15, 0.17-0.19 g/kg, respectively, which was lower than the SOC and TN contents of natural secondary forests, and lower than the national average values of SOC, TN and TP contents of forests. The microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) showed a trend of gradual increase with elevation, and the microbial biomass phosphorus (MBP) content overall showed a decreasing trend with elevation, with the range of 237.46-398.26, 23.04-30.74, 4.77-9.59 mg/kg, respectively, and with the TP contents. TP showed highly significant positive correlation (P<0.01). The differences were not significant compared with those of natural secondary forests at the same elevation. MBC/MBN, MBC/MBP and MBN/MBP all tended to increase with elevation, with ratios ranging from 9.05-13.17, 24.73-80.99 and 2.76-6.60. At 500 m, the MBC/MBP and MBN/MBP of the Eucalyptus plantation were significantly different from those of the natural secondary forest.. The variation of microbial quotient carbon (qMBC), microbial quotient nitrogen (qMBN) and microbial quotient phosphorus (qMBP) at different elevations was 1.89%-3.34%,2.90%-3.23% and 1.33%-5.41%, respectively. qMBC showed a gradual increase in elevation, and qMBP declined with the elevation. qMBC and qMBP were higher than those of natural secondary forests. qMBC and qMBP were higher than those of natural secondary forests. Soil organic carbon and total nitrogen were the key factors affecting the changes. In conclusion, the elevation gradient has a significant impact on the content and stoichiometric ratio of soil-microbial carbon, nitrogen, and phosphorus in Eucalyptus plantations. Compared with natural secondary forests at the same elevation, the soil of Eucalyptus plantations exhibited a deficiency in carbon and phosphorus contents, but enhanced the conversion efficiency of soil carbon and phosphorus to microbial biomass carbon and phosphorus. Based on this, the Eucalyptus plantations in the park should be conserved, and attention should be paid to the influence of carbon and phosphorus elements in the subsequent management.

SOC1 (SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1) is a flowering time regulator in plants. It belongs to the MADS-box transcription factor family and plays a crucial role in the transition from vegetative to reproductive growth in plants. SOC1 is involved in various biological processes, including flower organ development, flowering time control, and response to environmental stimuli and hormone signals. In this study, shading and application of Lorsben were used for flower induction in wax apple, and the number of leaf buds, flowers, and the rate of flowering shoots were recorded after treatment. Additionally, the existing transcriptome data of wax apple in our research group were analyzed to identify the candidate gene SsSOC1 involved in regulating flowering in wax apple. The differential expression of SsSOC1 in different stages and tissues of wax apple under shading and Lorsben treatment was studied using qPCR. The results showed that the expression of the SsSOC1 gene significantly increased in the buds, leaves, leaf tips, and petioles of wax apple treated with shading, with the highest relative expression in the leaf tips. In this study, the SsSOC1 gene from Hei Tang Ba Bi wax apple was successfully cloned, and its promoter analysis, physicochemical properties of the protein, prediction of conserved functional domains, and sequence alignment were performed using bioinformatics methods. The open reading frame of the SsSOC1 gene in wax apple was found to be 654 bp, encoding a protein of 217 amino acids. The theoretical isoelectric point of the protein was 9.37, with a molecular formula of C₁₀₇₆H₁₇₉₄N₃₂₂O₃₃₄S₁₀ and a molecular weight of 24.91 kDa. The protein contained 40 positively charged amino acid residues (Lys+Arg) and 32 negatively charged amino acid residues (Asp+Glu). The protein had a fat coefficient of 80.64, a grand average of hydropathicity (GRAVY) of -0.729, and an instability coefficient of 66.17. The protein structure lacked β-folds and did not belong to secretory or membrane proteins. Subcellular localization analysis indicated that the protein was mainly present in the nucleus and belonged to an unstable hydrophilic basic protein. The SsSOC1 protein in wax apple possessed conserved domains including MADS_MEF2_like and K-Box and belonged to the MADS superfamily and K-Box superfamily. The analysis identified the amino acid positions 3 to 75 and 88 to 171 as the start and end sites of the conserved domains, respectively, conforming to the typical structural features of the MADS protein family and the K-Box family. The evolutionary tree showed the highest homology between the SsSOC1 sequence in wax apple and Syzygium oleosum. By floral dip transformation, the SsSOC1 gene was introduced into Arabidopsis, and it was found that the 35S::SsSOC1 line exhibited an early flowering phenotype and a reduced number of rosette leaves compared to the wild type. This study preliminarily elucidated the important role of the SsSOC1 gene in flowering in wax apple and attempted to reveal the intrinsic regulatory mechanism of shading-induced flowering, providing guidance for wax apple production and theoretical basis for improving out-of-season cultivation techniques.

Endoclita vietnamensis Buchsbaum & Grehan, a newly discovered pest of dried Eucalyptus, is a typical example of native insect adaptation to an alien host. Adult larvae scatter the eggs on the ground below the forest, and the larvae live in the litter layer to the third stage after hatching, and then transfer the damage to the tree. Even in mixed forests, larvae can accurately locate the host, which leads to be assumed that the olfactory system of larvae is conducive to host selection. In addition, the olfactory system also plays an important role in the mating process of adult worms. Here, we studied the transcriptome of the head, chest and abdomen of the 5th instar, 12th instar and antennal antennae of the adult, and investigated the expression profile of olfactory proteins. A total of 66 olfactory proteins were identified,14 of which were newly identified, including three odor-binding proteins (OBPs), four odor receptors (ORs), one taste receptor (GRs), and six ionic receptors (IRs). The expression profiles showed that all OBPs, ORs and GRs were expressed to varying degrees in the three stages, except OR22 and OR25 which were not expressed in the head of the 5th instar larvae. The expression level of EsigOR23 was the highest among all olfactory proteins, and was significantly high in the head of 5th instar larvae. The expression of EsigGOBP9 in adult antennae was significantly higher than that in adults at 5 and 12 ages. This study would provide a molecular basis for further study of the chemical sensation of the E. vietnamensis. EsigOR23 and EsigGOBP9 have unique expression patterns, which may be important proteins affecting host selection in larvae and courtship behavior in adults, respectively, and deserve further exploration.

Manganese (Mn) is a crucial element influencing the performance of natural rubber. This study investigated the effects of different fertilization strategies on Mn content in soil, rubber tree (Hevea brasiliensis Muell. Arg.) roots and leaves, latex and raw rubber, and the subsequent impact on rubber properties in rubber plantations. The aim was to provide theoretical insights for optimizing rubber tree fertilization and enhancing natural rubber properties. Field experiments were conducted from 2022 to 2023 in a RY 73397 variety rubber plantation. Quantitative fertilization was applied to individual rubber trees using a composite approach involving hole application and tapping panel. The control group received no fertilizer treatment (CK), while five different fertilization treatments were implemented: 2 kg sodium silicate (T₁), 0.5% zinc molybdate fertilizer (T₂), 5 kg biochar (T₃), 5 kg biochar+0.5% zinc molybdate fertilizer (T₄) and 5 kg biochar+0.5% zinc molybdate fertilizer+2 kg sodium silicate (T₅). Samples were collected during various months of latex production period to determine dry rubber yield, Mn content in various samples (soil, roots, leaves, latex, raw rubber), and rubber properties under different fertilization strategies, analyzing their effects on Mn content and rubber properties within the soil-rubber tree system. The rubber yield from different treatments ranged from 44.96 g to 62.90 g. Treatments T₁, T₃, T₄ and T₅ increased soil pH value, and effectively transformed bioavailable forms of Mn into less available forms for rubber trees in soil, with treatment T₅ being most effective. Treatment T₅ also significantly reduced Mn content in rubber tree roots. The application of T₄ and T₅ treatments significantly reduced Mn content in latex. Treatment T₁ was effective in enhancing the plasticity retention, while treatments T₂, T₃, T₄ and T₅ were capable of improving the initial plasticity of raw rubber. Treatments T₄ and T₅ significantly increased the Mooney viscosity. Following the implementation of T₂, T₃, T₄ and T₅ treatments, the initial plasticity, plasticity retention, and Mooney viscosity of natural rubber all complied with the General Specifications for Natural Rubber Used in Aircraft Tires. The number-average molecular weight and weight-average molecular weight of raw rubber under different treatments ranged from 35.25×10⁴ to 39.57×10⁴ and from 161.84×10⁴ to 167.32×10⁴, respectively, while also decreasing the molecular weight distribution. To summary, the combined application of biochar, sodium silicate, and zinc-molybdenum fertilizers can enhance soil conditions, affecting the yield of rubber trees and the manganese (Mn) content in both latex and raw rubber, which in turn influences the properties of raw rubber. Based on this study, the T₅ treatment (5 kg biochar+0.5% zinc molybdate fertilizer+2 kg sodium silicate per individual tree) is recommended for comprehensive enhancement of dry rubber yield and rubber properties.

In order to investigate the genetic diversity of phenotypes and improve the utilization efficiency of different germplasm resources in Phalaenopsis, 76 germplasm resources of Phalaenopsis were investigated on the phenotype diversity by differential analysis, correlation analysis, principal component analysis and cluster analysis. The ornamental value of big-flower, medium-flower and small-flower cultivars were evaluated comprehensively. The results showed that plant height was the most significant difference among the cultivars, and the flower number per plant was the largest coefficient of variation. Most phenotypes showed significant or extremely significant positive correlation. Flower width and length were the main factors leading to the genetic diversity of phenotypes in Phalaenopsis. The 11 phenotypes were divided into three categories by the R-type cluster analysis, among which flower length and width were clustered firstly when the Euclidean distance was 1.1, indicating the highest degree of correlation between them. 76 germplasm resources could be divided into three categories by Q-type cluster analysis, big flower, medium flower and small flower cultivars. In the comprehensive evaluation of ornamental value, the big flower Baihuahonxin, Huanying and V3, the medium flower Chulian, Huangpao, Jixiang, Memphis, 79, Ama and the small flower Auspicious, Xiaomeihua, Christmas Tree, LL29 and Queen Beer obtained higher scores. The results would provide a reference for the efficient utilization of germplasm resources and parent selection of crossbreeding in Phalaenopsis.

Sweet potato is often base fertilized with nitrogen and no further dressing nitrogen fertilizer is needed. It is important to develop and screen slow-releasing nitrogen fertilizers that could meet the nitrogen requirements of sweet potato at different growth stages in order to promote yield and reduce nitrogen rate. A greenhouse pot experiment using variety Sushu 16 was conducted to analyze the effects of different slow-releasing nitrogen fertilizers (urea formaldehyde, sulfur-coated urea, urea formaldehyde resin, urea combined with nitrification inhibitors) on leaf photosynthesis, above-ground and underground biomass and nitrogen content, nitrogen use efficiency, and soil mineral nitrogen (nitrate nitrogen and ammonium nitrogen) content at different growth stages of sweet potato (seedling stage, vine burying stage, bulking stage, and harvest stage). Compared with the control, the sulfur-coated urea and oxamide controlled-release nitrogen fertilizers increased the biomass of sweet potato roots by 96.79% and 103.59%, respectively, significantly higher than that of the urea-formaldehyde and urea combined with nitrification inhibitor treatments (P<0.05). In addition, the photosynthesis rate of sweet potato throughout the entire growth period was significantly higher in the sulfur-coated urea treatment than that of unfertilized control, which is beneficial to improving the biomass of sweet potato roots. The nitrogen releasing of sulfur-coated urea and oxamide was less in the seedling and closure period and more in the swelling period and harvest period. The sum of ammonium nitrogen and nitrate nitrogen was 1.24-1.60 times that of urea-formaldehyde and urea combined with nitrification inhibitor, and the nitrogen fertilizer utilization rate increased by 1.17-1.80 times. In conclusion, sulfur-coated urea and urea formaldehyde are more suitable for the one-time application of nitrogen fertilizer in sweet potato production. The study results could provide scientific basis for nutrient management and nitrogen fertilizer reduction and yield enhancement in sweet potato production.

The study was aimed to select suitable substrate formulations for seedling of Hainan cherry tomato rootstocks. Variety Haiqiezhen No.1 was used, and fermented cow dung, coconut husk, and commercial seedling substrate were made into eight substrate formulations according to different volume ratios, and commercial seedling substrate was used as the control (CK). The physicochemical properties of different seedling substrates and the effects on the growth and physiological characteristics of rootstock seedlings were investigated. The bulk density and aeration porosity of the seedling substrates with coconut busk and cow dung were lower than that of CK, while the total porosity, water-holding porosity, pH and EC were higher than that of CK. The nutrient contents of the treatments were basically higher than that of CK, and the differences reached a highly significant level. The emergence rate of each treatment was more than 90%, which was highly significantly higher than that of CK (except T₈). With the prolongation of seedling growth period, the plant height and stem diameter also increased, and there were large differences among different treatments. T₂ and T₄ were better than other treatments. Fresh and dry weight of the whole plant, above-ground and below-ground dry weights, and strong seedling index also increased with the addition of coconut busk and cow dung (except T₅ and T₆). The best treatment was T₄, and the strong seedling index reached 0.106, which was significantly higher than that of CK, and improved 36.05% compared with that of CK. Different seedling substrates had little effect on the main root length of seedlings, which could promote the increase of average root diameter, root surface area and root volume, but the root vigour was extremely significantly lower than that of CK. The comprehensive evaluation of principal components was T₄>T₃>T₂>T₆>T₇>T₅>T₈>T₁>CK. In summary, T₄ had optimum formula on Haiqiezhen No.1.