The No.1 Central document for 2026 emphasizes enhancing soybean production capacity, expanding the cultivation space for rapeseed, peanuts, Camellia oleifera, and other oil crops, and increasing the diversified supply of oilseeds. On this basis, how to further enhance the competitiveness of Guangdong's oilseed industry and achieve its high-quality development is of great significance for ensuring the supply of oil crops and the production of edible oil in China. This study analyzes the current situation of oil crop production, cost-benefit, mechanization and processing levels, and policy support in Guangdong Province. The results indicate that: (1) As a major producer of oil crops in China, Guangdong Province has maintained the third-largest peanut sown area in the country for years. Peanuts accounted for 50% of the increase in total sown area of oil crops in Guangdong Province, with western and northern regions contributing 70% of the province's total peanut production. (2) Oil crop production in Guangdong still requires substantial improvement, as peanut yields per mu and net profits remain relatively low, while production costs have risen excessively. Moreover, compared with Henan and Shandong Provinces, Guangdong exhibits a markedly lower level of comprehensive mechanization in oil crop cultivation. (3) Guangdong is a leading province in peanut and soybean breeding, and has been actively promoting "green, high-yield, and efficient" cropping systems. It ranks first nationwide in the number of edible oil processing enterprises and has been implementing multi-tier agricultural insurance schemes for oil crops. On this basis, the challenges faced by the oil industry in Guangdong Province were discussed as follows: Limited space promotion, slow selection and breeding of improved varieties, difficulty in promoting new varieties; The planting benefit is low, and the cost of labor and agricultural materials rises; Policy support system and farmers' awareness of policy need to be improved; Low degree of organization, insufficient extension of industrial chain; The construction of policy support system for oil crops needs to be improved. Accordingly, relevant policy suggestions were put forward for the development of oil industry in Guangdong Province: Strengthen the support of oil crop science and technology and equipment; Innovate the organizational forms and value chain extension of the oilseed industry; Enrich the financial and financial policy support system of the oil industry; Promote industrial spatial agglomeration and chain collaboration, and build modern oilseed industrial clusters.
Hormesis is an adaptive response in which organisms exposed to sub-toxic doses of stressors exhibit enhanced growth, metabolism, or stress tolerance. This phenomenon has recently shown significant potential for agricultural applications. This review systematically summarizes the molecular regulatory mechanisms, major application fields, and recent research progress of hormesis in agriculture. At the plant level, low doses of pesticides, heavy metals, and other toxic substances can promote photosynthesis, root development, and antioxidant capacity. However, such stimulatory effects are strictly concentration-dependent, and the ecological risks posed by bioaccumulation should be taken seriously. At the farmland ecosystem level, hormesis is widespread and multifaceted, displaying marked species specificity and concentration thresholds. Some low-dose pollutants may even affect plant population dynamics and agroecosystem stability through transgenerational effects. In the context of pest and disease management, hormesis exhibits a dual nature: sublethal doses of pesticides often alter pest reproduction and migratory behavior, thereby becoming a driving factor for resistance evolution; conversely, the same doses tend to be safer for natural enemies. In summary, hormesis represents a bidirectional regulatory strategy of biological systems near toxicity thresholds, carrying both beneficial and risky attributes. Future research should focus on establishing precise threshold determination models, exploring the use of hormesis for precision pest control and resistance management, and improving corresponding ecological risk assessment systems, thereby promoting green, precise, and sustainable agricultural production.
【Objective】Fungi associated with pine bark beetles are an important and distinctive fungal resource. In order to supplement the research data of this kind of fungi in related areas, the associated fungal resources of bark beetles in Pinus massoniana forests damaged by pine wilt disease in Qingyuan and Zhaoqing of Guangdong Province were investigated.【Method】Using tissue isolation and molecular sequencing techniques, this study compared the diversity and differences of fungal species among different regions. Molecular phylogenetic analyses based on the internal transcribed spacer (ITS), large subunit ribosomal RNA (LSU), β-tubulin (TUB2), and translation elongation factor (TEF-1α) gene fragments, together with morphological characterization, were used to describe newly discovered species. Plate co-culture and the Baermann funnel method were employed to measure the effects of representative fungal strains on the reproduction of the pine wood nematode.【Result】A total of 42 samples were collected. After isolation and purification, 382 fungal isolates were obtained. There were 224 strains of 7 genera of Ophiostomatales: Ceratocystiopsis, Graphilbum, Ophiostoma, Leptographium, Masuyamyces, Raffaelea, and Sporothrix. Ophiostoma ips was the dominant species, accounting for 32.59% of the total number of the ophiostomatoid isolates. The next most common were Ceratocystiopsis sp. and Sporothrix zhejiangensis, representing 23.70% and 22.30% of the isolates, respectively. The one undescribed taxon discovered was proposed as a new species, named Masuyamyces qingyuanensis sp. nov.. Nine kinds of ophiostomatoid fungi were selected to co-culture with pine wood nematode. The results showed that the strain Raffaelea subfusca had the best effect, and the instantaneous growth rate (IGR) of pine wood nematode was 0.48 after 3 days of co-culture, while the strain M. cf. lotiformis had the highest growth inhibitory activity against pine wood nematode, and the IGR of pine wood nematodes was only 0.27 after 3 days of co-culture.【Conclusion】The diversity of fungi associated with bark beetles is relatively high in both Qingyuan and Zhaoqing, and although the species composition of the communities differs between the two regions, the dominant species are consistent. All the tested blue-stain fungi exhibited varying degrees of inhibitory effects on the reproduction of pine wood nematode.
Guangdong Province ranks first nationwide in both longan planting output and consumption, serving as a key representative of the southern subtropical characteristic fruit industry.Based on Guangdong provincial industrial statistics data from 2016 to 2025, this paper analyzes the development trends, bottlenecks and transformation paths of the longan industry in Guangdong Province. The study draws the following findings: (1) In terms of scale and structure, the province's longan planting area remains stable at 1.156×105 hm2. Although it accounts for 43.20% of the national total planting area, the industry suffers from excessive concentration of varieties and prominent homogenization. (2) With regard to production efficiency and spatial layout, western Guangdong producing areas possess strong price competitiveness by virtue of early-maturing varieties. In contrast, the Pearl River Delta producing areas face diminishing marginal returns and rigid increases in factor costs, leading to a declining comparative advantage. (3) From the value chain perspective, production costs have risen by 36.20% over the decade. Coupled with shifts in the international trade environment, the local industry is confronted with severe challenges including "output growth without income growth" and hindered exports. Further analysis reveals that the insufficient resilience of the industrial chain is mainly reflected in lagging variety innovation, low mechanization rate in mountainous orchards and a low processing conversion rate. Accordingly, during the 15th Five-Year Plan period, the longan industry in Guangdong Province should take seed industry innovation as the core driving force, adopt "mechanization-suitable orchard transformation + smart agriculture" as production support, rely on graded processing and loss reduction & efficiency improvement as value-added approaches, and implement green prevention and control alongside brand building as quality guarantees. The conclusions of this research not only provide empirical evidence for addressing homogeneous competition and inefficient supply within Guangdong's longan industry, but also offer insights for China's southern subtropical characteristic fruits to engage in international competition and achieve coordinated development of the domestic and international dual circulation.
【Objective】During the artificial breeding of Begonia, "false hybrids" frequently arise as a result of self-pollination or parthenogenesis, while traditional morphological identification and conventional molecular marker methods have limited capacity to distinguish them from true hybrids. To address these challenges, this study aims to develop a set of specific EPIC (Exon-primed intron-crossing) molecular barcodes suitable for the early and accurate identification of Begonia F1 hybrids.【Method】First, single-copy orthologous genes were identified using the whole-genome data of four representative Begonia species; highly variable regions were then screened, and intron-spanning amplification primers were designed. Subsequently, parents such as B. boweri cv. Tiger, together with six derived putative hybrid combinations, were selected as experimental materials for PCR amplification and Sanger sequencing. Finally, by aligning the sequences of parents and hybrid progenies, diagnostic single nucleotide polymorphisms (SNPs) and insertion/deletion (InDel) mutations were identified and quantified.【Result】From 5 141 single-copy orthologous groups, four high-resolution EPIC barcode fragments (Bpe025368, Bpe012331.1, Bpe012357.1, and Bpe012390.1) were successfully screened and validated. Sequence alignment showed that true hybrids displayed characteristic biparental additive base peaks (overlapping peaks) at diagnostic sites, exhibiting typical biparental inheritance. For example, in the true hybrid B. heracleifolia cv. nigricans × B. cirrosa, the proportion of diagnostic SNP reached 100%. In contrast, false hybrids (such as the B. heracleifolia × B. heracleifolia cv. nigricans combination) exhibited homozygous single-parent inheritance, with an extremely low proportion of diagnostic SNP (0%~11.5%). Based on a comprehensive evaluation of amplification stability and sequencing clarity across all markers, Bpe012331.1 demonstrated the optimal identification efficacy and is recommended as the core marker.【Conclusion】By exploiting the additive inheritance of nuclear genes, the EPIC barcode system developed in this study enables stable, rapid, and cost-effective identification of true and false Begonia F1 hybrids. It provides a reliable molecular tool for germplasm resource conservation, new variety registration (DUS testing), and early-stage marker-assisted breeding.
【Objective】This study aimed to investigate the effects of various mulching films on agronomic traits, yield, economic value, and volatile metabolites of flue-cured tobacco variety 'Yueyan 97', providing theoretical basis for the precise selection of mulching films in Nanxiong tobacco-growing areas.【Method】The dominant flue-cured tobacco cultivar 'Yueyan 97' widely cultivated in Guangdong tobacco-growing regions was used as the experimental material. Four mulching film treatments were established, including black-transparent film (BW, transparent in the middle with black edges), fully transparent film (W), silver-transparent film (YGW, transparent in the middle with silver edges), and pure silver film (YG). The application effects were comprehensively evaluated by measuring agronomic traits at maturity, grading yield and value, and analyzing volatile components in tobacco leaves.【Result】In terms of agronomic traits, plant height of the W treatment was significantly higher than that of YG, and the maximum leaf length in the BW treatment was significantly lower than YG. There were no significant differences in the number of effective leaves and maximum leaf width among the four mulch treatments. The YG treatment possessed the optimal position of the maximum leaf and the most uniform population growth. In terms of yield and output value, YG had the highest proportion of upper leaves, yield and output value, while treatment W presented the worst comprehensive production performance. A total of 89 volatile compounds from eight chemical groups were identified by GC-MS. The range of relative content of esters was 16.630%, which was affected most obviously by mulch types, whereas alkenes showed the weakest response. Principal component analysis (PCA) demonstrated that YG and W shared similar metabolic profiles, while BW and YGW formed separate clusters. The contents of core aroma substances including esters, trans, trans-farnesol and α-ionone in BW tobacco leaves were significantly higher than those of other treatments, with the lowest concentration of harmful myosmine. Geraniol also reached the highest level under BW treatment, with no significant difference compared with the YGW treatment. Treatment YG accumulated high levels of alcohols and dihydroactinidiolide, but its characteristic aroma components were relatively low and the myosmine content was higher. The W and YGW treatments had certain advantages in ketone accumulation without prominent comprehensive performance.【Conclusion】Comprehensively considering agronomic performance, economic output and aroma quality, BW treatment slightly reduced the maximum leaf length but significantly elevated the contents of aroma compounds and decreased harmful components in tobacco leaves, making it the optimal mulch film for high-quality flue-cured tobacco production in Nanxiong tobacco-growing areas. The YG mulch film is suitable for tobacco cultivation targeting stable plant growth and high accumulation of alcohol compounds, while W and YGW treatments show no obvious comprehensive advantages.
As the largest province in aquaculture in China, the shrimp and crab industry in Guangdong Province plays an important role in ensuring food security, increasing farmers' income, and promoting rural revitalization. Systematically analyzing its development status, core challenges and strategies holds great significance for promoting high-quality development. Based on official statistical data from the China Fishery Statistical Yearbook and field surveys in major production areas such as Zhanjiang and Yangjiang in 2014-2025, this study systematically reviews the development status and evolutionary trends of the industry from multiple dimensions including industrial scale, species structure, seed breeding, regional distribution, production mode, processing and circulation, and brand building. The results show that Guangdong's shrimp and crab industry has formed significant scale and regional advantages, with a total output of 1.4493 million tons in 2024, accounting for 14.71% of the national total, featuring a spatial pattern of freshwater aquaculture dominating in the Pearl River Delta and mariculture excelling in western Guangdong. However, the industry still faces severe challenges: heavy dependence on imported broodstock of Litopenaeus vannamei, dual constraints of environmental pressure and rising costs on traditional farming models, weak deep processing capacity, and limited regional brand premiums. Drawing on international and domestic experiences, this study proposes four major projects—seed industry revitalization, farming innovation, processing upgrading, and brand enhancement—supported by systematic policy guarantees, to provide decision-making references for breaking through bottlenecks and achieving high-quality development of the shrimp and crab industry in Guangdong Province.
【Objective】To address the problems of low utilization rate of above-ground parts and the shortage of fresh-eating varieties in root mustard (Brassica juncea var. megarrhiza) varieties, this study investigated the nutritional advantages of different root mustard germplasms and their various edible parts, aiming to provide a theoretical basis for their comprehensive application and variety breeding.【Method】Taking the local variety 'Yibin Root Mustard' as the control, this study determined the content of soluble sugar, soluble protein, chlorophylls, carotenoids, anthocyanins, ascorbic acid, total phenolics, flavonoid, glucosinolates, as well as antioxidant capacity in leaves and fleshy roots of three root mustard accessions 'Yibin Root Mustard' 'CJJ-7' and 'ZJJ-18'. Principal component analysis, correlation analysis and analysis of variance for genetic effects were also analyzed.【Result】The contents of bioactive substances and antioxidant capacity in leaves of the three root mustard accessions were significantly higher than those in fleshy roots. The soluble protein content in leaves was 1.57-2.83 times that in fleshy roots. The contents of total chlorophylls, total carotenoids, ascorbic acid, flavonoid and total phenolics in leaves were 58.33-99.02, 14.06-28.03, 1.39-2.29, 13.79-30.37 and 3.26-4.25 times those in fleshy roots, respectively. The total glucosinolates content in leaves was 1.56-3.84 times that in fleshy roots. 'ZJJ-18' exhibited the highest antioxidant capacity and total glucosinolates content in leaves. The contents of ascorbic acid, flavonoid, total phenolics, total glucosinolates and FRAP value in 'ZJJ-18' leaves were 1.12, 1.26, 1.27, 1.47 and 1.75 times those of 'Yibin Root Mustard' leaves, respectively. Anthocyanins were only detected in leaves of 'ZJJ-18'. The soluble sugar contents in fleshy roots of 'ZJJ-18' and 'CJJ-7' were 1.31 and 1.24 times those of 'Yibin Root Mustard', while the total glucosinolates content in fleshy roots were only 54.92% and 59.55% of 'Yibin Root Mustard', respectively.【Conclusion】Leaves of 'ZJJ-18' possess high contents of bioactive substances and strong antioxidant capacity, which could be used for processing pickled vegetables such as salted mustard greens. The fleshy roots of 'ZJJ-18' and 'CJJ-7' have high soluble sugar content and low glucosinolates content, making them suitable as fresh-eating root mustard cultivars.
To address the critical need for the high-quality transformation of the southern medicinal herbs (Nanyao) industry in Guangdong Province, this study systematically reviews its development status, analyzes the underlying causes of its key problems, and forecasts high-quality development pathways for the "15th Five-Year Plan" period. Based on literature research, policy analysis and survey data from the Guangdong Province modern agricultural industry technology system innovation team (Nanyao) for Southern medicinal materials, and using a combination of quantitative and qualitative methods, the study analyzes the current situation from four dimensions—germplasm resources, type structure and scale, industrial clusters and regional distribution, and the entire industrial chain and brands—and, for the first time, conducts a dedicated analysis of the industrial chain structure, value transmission, market supply-demand and competition. The results show that Guangdong possesses solid resources, with 4 692 medicinal resource species and a Nanyao cultivation area of about 280 000 hm2, and has formed an integrated industrial chain across the primary, secondary and tertiary sectors. However, value transmission is characterized by "strong in the middle and weak at both ends", with the processing sector capturing most of the value and the agricultural end holding weak bargaining power; combined with the competition of medicinal materials and the "non-grain" policy constraints on cultivated land, the industry still faces structural constraints in germplasm protection, standardized cultivation, regional layout and tri-industry integration. The roots of these problems lie not in a single cost factor, but in the friction between smallholder operation and modern standardization systems, the mismatch between market price signals and zoning guidance, and the imbalance of the value-distribution mechanism along the chain. For the "15th Five-Year Plan", it is suggested to work synergistically along six dimensions—scientific planning and layout, seed industry revitalization, ecological planting transformation, Good Agricultural Practice (GAP) for Chinese Herbal Medicines standardization, tri-industry integration and brand clustering—to accelerate the construction of a more resilient and competitive modern Nanyao industry system and provide a "Guangdong Paradigm" for the high-quality development of Chinese medicinal materials nationwide.
To alleviate the tight constraints on land resources in South China and lay a solid foundation for regional food security, based on the industrial statistics and targeted research data of Guangdong Province, this paper systematically examines the development characteristics and optimization paths of the three major dry grains - sweet potatoes, corn, and potatoes from 2015 to 2024. The research findings are as follows, the scale of the industry has steadily expanded, but the trends of different categories have significantly diverged. The planting area, total output, and yield per unit area of dry grains have increased from 34.04×104 hm2, 157.66×104 t, and 4 631.6 kg/hm2 in 2015 to 35.49×104 hm2, 177.30×104 t, and 4 996.2 kg/hm2 in 2024 respectively. Among them, the planting area, output, and per unit yield of sweet potatoes have simultaneously improved, and the development is the most stable; the yield of corn has shown a prominent increase, presenting a feature of quantity and efficiency coordination; potatoes have been under pressure from insufficient policy supply and relatively low comparative benefits, and their planting area and output have continued to decline, which is the main bottleneck restricting balanced development. The production spatial clustering pattern of the three major dry grain industries in Guangdong is clear. The main production areas of sweet potatoes are concentrated in the western and eastern regions of Guangdong Province, which account for about 65% of the total in Guangdong. Corn is centered in the western region of Guangdong Province, and potatoes are mainly concentrated in the western part of the Pearl River Delta. The shortcomings of the full industrial chain collaboration remain prominent, manifested as increased risks of price fluctuations in the market, insufficient processing, storage and transportation capabilities, weak commercialization of scientific and technological achievements, and low levels of organization and socialization services of business entities. To address this, a implementation path centered on monitoring and early warning of production and sales big data, dual-chain collaboration of processing, storage and transportation and brand, collaborative innovation in green production of seed industry and agricultural machinery, and multi-departmental provincial-level linkage guarantee is proposed, with the aim of optimizing resource allocation, enhancing regional food security capacity, and providing empirical evidence for the improvement and efficiency enhancement of the South China dry grain industry.
【Objective】This study aims to investigate the effects of organic fertilizer substituting chemical fertilizer at equal-nitrogen ratios on the agronomic traits of tobacco plants, as well as on leaf yield, quality, and combustibility, so as to provide technical support for scientific fertilization in tobacco production.【Method】Using the cigar tobacco variety 'SCX4' as experimental material, a field plot experiment was conducted. With identical nitrogen, phosphorus and potassium application amounts, six treatments of organic fertilizer substituting 0%, 10%, 20%, 30%, 40%, and 50% of chemical fertilizer at equal nitrogen ratios, denoted as CK, M1, M2, M3, M4, and M5, respectively. Agronomic traits of tobacco plants, leaf quality grade proportions, yield, output value, chemical composition, and combustibility were measured, and a comprehensive evaluation was performed using the entropy-weighted TOPSIS method.【Result】As the substitution ratio increased, plant height, stem girth, internode length, and maximum leaf area at topping stage all significantly decreased. CK and M1 exhibited the best agronomic traits, with no significant differences in all indicators except plant height between them, and both were significantly superior to the other treatments. M5 showed the poorest agronomic traits, with plant height, stem girth, internode length, and maximum leaf area decreasing by 23.05%, 14.11%, 17.24%, and 34.98%, respectively, compared with CK. Compared with CK, M5 significantly reduced yield by 23.75%, while M1-M4 showed no significant differences. M1 achieved the highest output value of 145 288 yuan/hm2, which was 22.9% higher than that of CK. The proportion of first-grade leaves in M1-M5 was significantly higher than that of CK, with an average increase of 282.95%, and M1 had the highest proportion at 43.23%. With increasing substitution ratio, the reducing sugar content, sugar-to-nicotine ratio, and potassium-to-chlorine ratio in M1-M5 decreased compared with CK, with average reductions of 49.12%, 50.48%, and 52.58%, respectively. The chlorine content in M4 and M5 was significantly higher than that in CK. Correlation analysis revealed that gray value was significantly positively correlated with combustion speed, total sugar content, reducing sugar content, and sugar-to-nicotine ratio, and the key factors influencing gray value were sugar-to-nicotine ratio and combustion speed. The combustion speed and gray value of M1-M5 were lower than those of CK, with average reductions of 35.00% and 8.10%, respectively, indicating more complete combustion and ash color tending toward gray or grayish-white. Comprehensive evaluation of agronomic traits, yield, quality, and combustibility across all treatments ranked the comprehensive scores in descending order as M1、M4、M2、M3、M5、CK.【Conclusion】Organic fertilizer substituting chemical fertilizer at equal nitrogen rates can increase tobacco output value, raise the proportion of first-grade leaves, harmonize chemical composition, and improve leaf combustibility. The optimal equal-nitrogen substitution ratio of chemical fertilizer with organic fertilizer for cigar tobacco leaves is 10%.
[Objective]To clarify the effect of stem and vine pruning on the growth traits and the accumulation of constituents in the fleshy roots of Morinda officinalis How.[Method]This study used rejuvenated virus-free seedlings of the main cultivated variety'Heisuizai'from the Zhaoqing production area as experimental materials,set up two treatments:stem and vine pruning and unpruning.Field experiments were conducted for three consecutive years to observe plant growth indicators and determine the moisture,water-soluble extract,and nystose contents in fleshy roots.[Result]Compared with unpruned plants,stem and vine pruning significantly increased the number of stem branches and the emergence of new leaves.The maximum number of stem branches reached 22.00(±0.82)in pruned plants,compared with 17.00(±1.25)in unpruned plants;the stem diameter increased by 28.00％at 1 080 days;and the total number of leaves increased by 89.08％at 720 days.The later-stage chlorophyll content(SPAD value)was also significantly increased(P＜0.05).However,the leaf area of pruned plants was significantly lower than that of unpruned plants at 360～1 080 days(P＜0.05).Stem and vine pruning significantly induced the occurrence and enlargement of secondary and tertiary tillering roots.Compared with unpruned plants,the numbers of secondary and tertiary tillering roots at 1 080 days increased by 56.45％and 49.81％,respectively,and the fresh and dry weights of the underground parts increased by 28.00％and 27.00％.The harvest measurements at 1 080 days showed that the moisture,water-soluble extract,and nystose contents in the dried fleshy roots of pruned plants were 11.00％,68.40％,and 4.60％,respectively,while those in unpruned plants were 10.40％,73.30％,and 6.20％,respectively.The moisture,water-soluble extract,and nystose contents in the fleshy roots of both treatments were significantly higher than the pharmacopoeial standards.[Conclusion]Therefore,timely stem and vine pruning of virus-free M.officinalis plants can break apical dominance and induce the occurrence and enlargement of tillering roots.This practice effectively promoted root development and fleshy root biomass accumulation,thereby improving the yield and medicinal geoherbal quality of M.officinalis medicinal materials.
【Objective】To clarify the effects of nitrogen forms and concentrations on the growth, root morphology, photosynthetic pigment contents and nutrient uptake of pineapple seedlings, this study screened the optimal form and concentration of nitrogen for pineapple seedling stage, so as to provide technical support for the scientific nitrogen application for pineapple seedling stage.【Method】Seedlings of pineapple cv. 'Bali' were used as test materials and cultivated with nutrient solution. Two nitrogen forms, ammonium nitrogen(AN) and nitrate nitrogen(NN), were set in three nitrogen concentration gradients of 0.5, 2.0, and 4.0 mmol/L, generating six treatments, namely AN0.5, AN2.0, AN4.0, NN0.5, NN2.0 and NN4.0. Indicators including dry matter accumulation, leaf and root morphology, chlorophyll content, nitrate nitrogen and ammonium nitrogen concentrations, as well as the accumulation amounts of nitrogen, phosphorus, and potassium were determined.【Result】Ammonium nitrogen facilitated aboveground dry biomass of pineapple seedlings. The dry weight of leaves under the AN0.5 and AN2.0 treatments increased significantly by 106.02% and 55.83%, respectively compared to the NN treatment in equivalent nitrogen concentrations. The dry weights of leaves and aboveground stems decreased with increasing nitrogen concentration under AN treatments, indicating that high ammonium nitrogen concentration inhibited aboveground growth. Underground stem dry weight decreased first and then rose with rising nitrogen concentration. Both AN and NN treatments exhibited the lowest underground stem dry weight under the nitrogen concentration of 2.0 mmol/L.Root dry weight increased with elevated nitrogen concentration. Only the AN2.0 treatment had significantly higher root dry weight than the NN2.0 treatment, while no significant differences in root dry weight were detected between AN and NN treatments in all other corresponding nitrogen concentrations. The total dry weight of pineapple seedlings under AN0.5 and AN2.0 treatments was significantly increased by 54.51% and 37.45%, respectively, compared with the NN treatments in the corresponding nitrogen concentrations. Pineapple seedlings under AN treatments exhibited superior morphological indices relative to NN treatments, and the total leaf area of the AN0.5 treatment was markedly higher than that of all NN treatments. With the increase of nitrogen concentration, root length of AN treatments first increased and then decreased, root length of NN treatments increased continuously. The AN0.5 treatment had the highest leaf total chlorophyll content, reaching 0.56 mg/g. Ammonium nitrogen was more conducive to the absorption of nitrogen, phosphorus, and potassium by leaves. Compared with NN treatments in equivalent nitrogen concentrations, leaf nitrogen contents under AN treatments were significantly increased by 11.33%-14.78%, and leaf phosphorus contents under AN treatments were significantly elevated by 66.21%-162.55%. Compared with NN treatments in equivalent nitrogen concentration, leaf potassium contents of AN0.5 treatments were significantly increased by 18.75%, while leaf potassium content of AN4.0 treatment was significantly reduced by 10.92%. There was no significant difference in leaf potassium content between AN2.0 and NN2.0 treatments. Principal component analysis extracted three principal components with a cumulative variance explained ratio of 85.75%. Comprehensive evaluation via the membership function method showed that the AN0.5 treatment exhibited the optimal comprehensive performance in pineapple seedling growth and nutrient uptake.【Conclusion】Ammonium nitrogen is the optimal nitrogen form for pineapple seedlings. A 0.5 mmol/L ammonium nitrogen concentration maximizes pineapple seedling growth, photosynthetic pigment synthesis and nutrient uptake, whereas high ammonium nitrogen concentrations suppress aboveground growth.
【Objective】The study was aimed to clone the terpenoid synthase gene CcTPS26 from Cinnamomum cassia Presl, characterize its sequence features, conserved domains, phylogeny and spatiotemporal expression, and obtain soluble recombinant protein via prokaryotic expression, so as to lay a solid foundation for elucidating the molecular mechanism of terpenoid biosynthesis and validating enzymatic function in cinnamon.【Method】The full-length coding sequence of CcTPS26 was cloned from C. cassia. Bioinformatics tools were employed to analyze the physicochemical properties, conserved domains, subcellular localization, promoter cis-elements, and phylogenetic relationships of the encoded protein. Molecular docking was performed to evaluated the binding affinity of CcTPS26 with FPP and GPP. The prokaryotic expression vector was constructed and transformed into Escherichia coli BL21(DE3), and recombinant protein expression was induced by IPTG. The molecular weight and solubility were determined by SDS-PAGE, and the protein was purified by Ni2+ affinity chromatography. Transcript levels of CcTPS26 in different tissues and phloem at different developmental stages were quantified by qRT-PCR.【Result】The full length open reading frame (ORF) of CcTPS26 was 1 686 bp, encoding 561 amino acids with a theoretical molecular weight of 64.94 kDa and an isoelectric point (pI) of 5.60. CcTPS26 was predicted as a hydrophilic, acidic and unstable protein without signal peptide or transmembrane domains, and was primarily localized in the cytoplasm. It contained the Terpene cyclase plant C1 domain and the Class Ⅰ IPS conserved motifs DDXXD and NSE/DTE. Phylogenetic analysis revealed that CcTPS26 shared the highest identity (93.76%) with the TPS from C. burmanni. Abundant stress- and hormone-responsive cis-elements were detected in the promoter region, suggesting transcriptional regulation by stress and hormonal signals. Molecular docking confirmed that CcTPS26 could stably bind GPP and FPP through hydrogen bonds and salt bridges. The soluble recombinant protein of approximately 82.1 kDa was successfully expressed and purified, with the highest purity achieved at 275 mmol/L imidazole elution. CcTPS26 exhibited distinct tissue- and development-specific expression: transcripts were significantly more abundant in fruits, leaves, and the phloem than in flowers and xylem, and peaked in the phloem of 5-year-old trees.【Conclusion】The terpene synthase gene CcTPS26 was first cloned and characterized from C. cassia. The encoded protein can specifically recognize the key precursors for terpenoid biosynthesis. Its sequence characteristics, spatiotemporal expression patterns, and optimal conditions for recombinant protein purification were determined. CcTPS26 is predominantly expressed in terpenoid-accumulating tissues and presumably plays an essential role in the biosynthesis of terpenoids. This work provides a key candidate gene for terpenoid metabolism regulation and molecular breeding in C. cassia.
【Objective】Aiming at the bottlenecks in seedling propagation of Cinnamomum loureirii Nees., this study established an efficient cutting propagation technical system for the species, to provide key technical support for the vegetative propagation and large-scale standardized production of high-quality seedlings of C. loureirii.【Method】C. loureirii cuttings were used as experimental materials in this study. The effects of different cutting substrates, plant hormone types, indole-3-butyric acid (IBA) concentrations and soaking time on rooting rate and seedling growth of C. loureirii cuttings were systematically explored. Single-factor preliminary experiments were firstly carried out to clarify the influence rule of each single factor on the rooting survival and new shoot germination of C. loureirii cuttings. On this basis, a four-factor and three-level orthogonal experiment was designed, and range analysis was performed to comprehensively analyze the effects of various factors on multiple growth indicators of cutting seedlings.【Result】Hardwood cuttings were more suitable for the cutting propagation of C. loureirii than softwood cuttings. Among tested cutting substrates, the equal-volume (1∶1) mixed substrate of peat soil and loam exhibited the best cutting performance, with a rooting rate of 75.00%, followed by pure peat soil (70.83%) and the 1∶1 mixed substrate of loam and river sand (70.00%). In terms of hormone treatments, IBA, NAA and ABT all showed significant rooting-promoting effects, with the rooting rate of 76.67%, 75.83% and 72.50% respectively. The IBA treatment with a concentration of 200 mg/L and soaking time within 30 min achieved the highest rooting rate of cuttings, while the 400 mg/L IBA concentration was conducive to the growth of new shoots and root systems of cuttings. The range analysis of orthogonal test results indicated that hormone soaking time and hormone concentration were the dominant factors affecting the rooting and growth of C. loureirii cuttings.【Conclusion】For the cutting propagation of C. loureirii, hardwood branches are the optimal cutting materials. The equal-ratio mixed substrates of peat soil and loam or loam and river sand are suitable for cutting cultivation. Soaking cuttings in 200 mg/L or 400 mg/L IBA solution within 30 min can obtain a high rooting rate and excellent seedling growth performance. This technical system is simple and convenient to operate, which can effectively support the seedling breeding of C. loureirii and provide a practical basis for large-scale clonal seedling cultivation in suitable areas such as Guangdong Province.
【Objective】Fasciclin-like arabinogalactan proteins (FLAs) were a subclass of arabinogalactan- proteins (AGPs). The FLAs were widely involved in biological processes such as plant growth and development, sexual reproduction, and abiotic stress response. Identifying and analyzing the FLA gene family in Rosa plants (R. chinensis and R. rugosa) could help to understand the role of the FLA gene family in the biological processes of Rosa plants.【Method】This study employed bioinformatics to conduct a genome-wide identification of the FLA gene family in R. chinensis and R. rugosa. The FLA gene families of the two species were compared, and the expression patterns of FLA genes in the stamens and pistils of R. chinensis and R. rugosa were analyzed.【Result】Twenty-five FLA genes were identified in both R. chinensis and R. rugosa, unevenly distributed across their respective seven chromosomes. Analysis of the structure of FLA genes in R. chinensis and R. rugosa revealed that 18 RcFLA in R. chinensis and 21 RrFLA in R. rugosa did not contain introns. Analysis of cis-regulatory elements found that light response elements, MeJA response elements, and auxin-related cis-elements were widely distributed. Among all 50 FLA proteins, 33 had signal peptides at their N-termini, 30 were transmembrane protein, and all 44 were likely localized on the cell membrane. The closely related FLA proteins showed strong similarity in their two-dimensional and three-dimensional structures and motif distribution. Phylogenetic analysis divided all FLAs into six groups, with Group Ⅰ having the most members and branches, and other groups containing FLAs from both R. chinensis and R. rugosa. Analysis of the expression patterns of FLA genes in the stamens and pistils of R. chinensis and R. rugosa revealed that some FLA were specifically highly expressed in the stamens or pistils.【Conclusion】A total of 25 FLA genes were identified in both R. chinensis and R. rugosa, indicating that these FLA genes are conserved and also species-specific. Additionally, some FLA genes were specifically highly expressed in the pistil or stamen, and were potentially involved in the fertility regulation of R. chinensis and R. rugosa, providing a reference for further research on the regulation of reproductive development in Rosa plants.
In the cultivation and production of Amomum villosum Lour., the common fruiting barrier problem characterized by "abundant flowers but scarce fruits" is widely observed. In the absence of pollinating insects, its natural fruit setting rate is only 5%-8%, which severely restricts the large-scale development of A. villosum. industry. Artificial assisted pollination can increase the fruit setting rate of A. villosum to 30%-50%, but this method is time-consuming, labor-intensive, and costly, making it difficult to popularize on a large scale. This paper systematically analyzes and explores approaches to address the fruiting barrier of A. villosum, and systematically reviews the current status and research progress of studies on the fruiting barrier of A. villosum from three aspects based on relevant research achievements at home and abroad. First, starting from botanical characteristics, this paper explains the physiological basis of its high dependence on obligate pollinating insects and low natural pollination efficiency from the perspective of internal factors including the special floral structure, flowering habits and self-incompatibility of A. villosum. Second, the internal constraints of genetic regulation mechanisms: the genetic basis of A. villosum germplasm resources are diverse, and genetic differentiation has occurred among different geographical populations; the pseudo-gynostemium and self-incompatibility formed by the genetic basis, as well as poor pollination and fertilization, lead to a sharp increase in endogenous abscisic acid and relatively insufficient auxin and gibberellin. The abscission layer formation signal controlled by the genetic basis initiates ovary abscission, which becomes a key factor restricting fruit setting. Third, the superposition of environmental stress factors: for example, a shading degree outside the range of 0.5-0.6 will affect the growth of A. villosum plants; low temperature during the flowering period inhibits pollen germination and pollen tube elongation, while high temperature accelerates pollen inactivation and stigma wilting; continuous rainy weather with insufficient light weakens the accumulation of photosynthetic products, impairs the development of floral organs, and hinders pollination by pollinating insects; insufficient nutrient elements intensifies the carbon and nitrogen nutrient competition between vegetative growth and reproductive growth, reducing the number of flowers; diseases and pests can directly damage the growth of floral organs. The cumulative effect of these environmental factors easily causes a large number of flower and fruit abscission, reducing the fruit setting rate. In conclusion, the fruiting barrier of A. villosum results from the combined interaction of pollination restriction by floral organ morphology, multi-level genetic basis regulation, and compound environmental stress, and these three factors interact with each other. The genetic basis determines the reproductive tolerance threshold of the plant, the special floral organs amplify the negative impact of environmental stress, and environmental adversity further disrupts endogenous hormone regulation and the expression of flower development genes. The interactive coupling of these three types of factors forms a positive feedback cascade, which constitutes the systematic root cause of the fruiting barrier of A. villosum. Aiming at the prominent problem of the fruiting barrier of A. villosum, this paper reviews technical strategies for flowering period regulation and fruit retention: first, improve the effective pollination efficiency in the field through artificial assisted pollination, and the protection and domestication of obligate pollinating insects; second, rely on traditional breeding and molecular breeding technologies to screen excellent germplasms adapted to different production regions, and improve floral organ traits and fruiting ability from the genetic level; third, optimize cultivation modes and implement environmental regulation to ensure effective pollination, fruit setting and normal fruit development of A. villosum. This study is expected to provide a theoretical basis and practical guidance for the revitalization and sustainable development of A. villosum industry.
Sweetpotato is an important crop for food, feed and industrial raw materials, playing a critical role in ensuring food security and promoting rural revitalization. However, during production and storage, sweetpotato is susceptible to infection by various pathogens including fungi, bacteria, viruses and nematodes, which leads to reduced yield and quality and has become one of the key factors restricting the development of the sweetpotato industry. Breeding and planting disease-resistant varieties is the most economical and effective strategy for controlling sweetpotato diseases. Traditional disease-resistant breeding relies on phenotypic selection, which is limited by long cycles, low efficiency and complex genetic backgrounds, making it difficult to meet the urgent industrial demand for elite disease-resistant varieties. In recent years, with the development of genomics, transcriptomics and molecular biology technologies, remarkable progress has been made in sweetpotato disease resistance research, including the identification of resistance genes, the dissection of signal transduction mechanisms and the application of molecular breeding. This review summarizes the major diseases of sweetpotato and their impacts, analyzes the resistance performance of nationally registered varieties, and outlines disease resistance-related genes and their regulatory mechanisms. In addition, the applications of molecular markers and QTL mapping, genetic engineering, and gene editing in resistance breeding are reviewed. Finally, the key challenges and future prospects of molecular breeding for disease resistance in sweetpotato are discussed, providing a theoretical basis for the development of resistant cultivars.
Pogostemon cablin (Blanco) Benth. (Patchouli), a perennial herbaceous plant belonging to the Pogostemon genus within the Lamiaceae family, stands as one of Chinese pivotal aromatic medicinal herbs. The dried aerial parts of this plant are utilized for their medicinal properties, which include dispelling dampness, regulating the middle energizer to alleviate nausea, and relieving summer heat. Its essential oil serves as a crucial raw material for various traditional Chinese patent medicines, such as Huoxiang Zhengqi Liquid and antiviral oral solutions, and finds extensive applications in the modern fragrance, cosmetics, and pharmaceutical industries, thereby holding substantial economic value and promising industrial prospects. Nevertheless, P. cablin is characterized by a lengthy growth cycle, sensitivity to environmental conditions, and a propensity for disease outbreaks during cultivation, all of which significantly compromise its yield and quality. These factors have emerged as primary obstacles to the high-quality development of the P. cablin cultivation sector. This study systematically reviews pertinent research literature from both domestic and international sources, summarizing prevalent diseases in P. cablin production, including bacterial wilt, Fusarium wilt, root rot, leaf spot, and mosaic disease, along with their field symptoms and epidemic patterns. It elucidates the biological traits, infection routes, and pathogenic mechanisms of key pathogens, such as Ralstonia solanacearum, Enterobacter spp., Fusarium spp., and Corynespora cassiicola. Regarding pathogen detection, advancements in traditional morphological identification, PCR-based molecular amplification, whole-genome sequencing (WGS), and nucleic acid isothermal amplification techniques (RPA/LAMP)-CRISPR are reviewed. In terms of disease management, comprehensive prevention and control strategies, encompassing agricultural, biological and chemical methods, are systematically analyzed. The disease-preventive potential of biological resources, including endophytic bacteria and plant growth-promoting rhizobacteria (PGPR), as well as the mitigating effects of biochar combined with organic fertilizers on continuous cropping obstacles, are emphasized. It is advocated that diverse prevention and control measures be organically integrated to establish a comprehensive field prevention and control system centered on biological control, coupled with the establishment of an efficient rapid pathogen detection platform to facilitate early disease warning and precise control. This endeavor aims to furnish vital references for the scientific prevention and control, stable and high yield, and standardized production of P. cablin.
【Objective】This study aims to characterize the mitochondrial genome of Plectropomus laevis and provide key molecular data for phylogenetic analysis, genetic diversity assessment, and germplasm conservation of this species.【Method】The complete mitochondrial genome of P. laevis was sequenced and annotated for the first time. Illumina sequencing technology was employed to obtain the whole-genome sequence. After assembly and annotation, bioinformatics analyses were performed, including base composition, codon usage bias, tRNA secondary structure prediction, and phylogenetic reconstruction based on 13 protein-coding genes (PCGs).【Result】The results showed that the complete mitochondrial genome of P. laevis is 16 771 bp in length, containing 13 PCGs, 2 rRNA genes, 22 tRNA genes, and a control region containing the heavy-strand origin (OH). No gene loss or rearrangement was detected, indicating a highly conserved structure. Base composition analysis revealed an overall AT content of 56.93%, with an AT-skew of 0.0120 and a GC-skew of -0.2318, which are typical characteristics of vertebrate mitochondrial bias. Except for cox1 (GTG) and atp6 (CTG), all other PCGs start with ATG. Among amino acids, leucine (Leu) showed the highest proportion (16.0%), while cysteine (Cys) had the lowest (1.6%). Relative synonymous codon usage (RSCU) analysis indicated that highly preferred codons predominantly end with A/U, and the codon usage pattern is highly similars to those of its congeneric species P. leopardus and P. areolatus, revealing conserved codon usage within the genus. Among the 22 tRNAs, all except trnS1 exhibited a complete typical cloverleaf secondary structure; the dihydrouridine arm stem of trnS1 retained only 2 base pairs, showing a highly reduced structure, a feature rarely reported in the family Epinephelidae. Phylogenetic trees constructed using neighbor-joining and maximum likelihood methods based on the 13 PCGs consistently supported the monophyly of the genus Plectropomus and suggested that Plectropomus may represent an early-diverging lineage within Epinephelidae.【Conclusion】The mitochondrial genome of P. laevis is highly conserved in structure and exhibits typical vertebrate nucleotide bias. Its codon usage pattern is highly conserved within the genus. The DHU arm of trnS1 is highly reduced, a feature rarely documented in Epinephelidae. Phylogenetic analysis confirmed the monophyly of Plectropomus and its placement as an early-diverging lineage.
