Natural rubber serum (NRS), a by-product generated during the processing of natural rubber (NR), contains all essential plant nutrients and numerous high-value bioactive components such as quebrachitol, ergothioneine, glutathione, and functional proteins, demonstrates significant resource utilization potential. Effective exploitation of NRS can not only mitigate environmental pollution and reduce disposal costs but also extend the NR industrial chain and enhance the economic benefits of the NR industry. In recent years, technological innovations in membrane separation, crystallization purification, fermentation, and biological extraction have facilitated substantial progress in the resource utilization of NRS. This paper systematically reviewed the component characteristics of NRS and advances in its application in multiple fields. It detailed the research and utilization of plant-derived nutrients in NRS, with a focus on the application progress of its bioactive components in high-value fields such as biomedicine and cosmetics. Finally, prospects for future applications were discussed, aiming to provide references for related research and support the green transformation and sustainable development of the NR industry.

Cadmium (Cd) is a highly mobile heavy metal in soil, exhibiting greater mobility than other heavy metals and readily entering the topsoil in free ionic forms, thereby facilitating uptake by crops. Application of silicon (Si) and zinc (Zn) fertilizers can modulate Cd accumulation in rice, while novel nano-fertilizers, owing to their unique physicochemical properties, effectively mitigate Cd stress. A pot experiment was conducted with six treatments: conventional fertilizer (CF), Cd + conventional fertilizer (Cd), Cd + conventional Si fertilizer (Cd+Si), Cd + nano-Si fertilizer (Cd+nSi), Cd + conventional Zn fertilizer (Cd+Zn), and Cd + nano-Zn fertilizer (Cd+nZn). This study investigates the effects of different Si and Zn fertilizer types on rice growth, Cd uptake, and translocation under Cd stress. The results revealed: (1) Under Cd stress, rice plant height, stem diameter, biomass, and root growth decreased significantly. Silicon and zinc fertilizers effectively alleviated Cd-induced growth inhibition. At the booting stage, nano-Si treatment restored plant height and stem diameter to levels comparable to the CF control. Compared with the Cd treatment, biomass increased by 38.68% (Cd+nSi) and 35.20% (Cd+nZn), while root fresh weight rose by 31.44% (Cd+nSi) and 24.84% (Cd+nZn). (2) Cd stress markedly reduced leaf chlorophyll content, suppressing chlorophyll biosynthesis. Foliar Si and Zn applications enhanced chlorophyll by 5.99%–7.68% and nitrogen content by 4.70%–8.19% at the booting stage, with nano-Si achieving the highest levels. (3) Soil pH increased notably after Si and Zn amendments, peaking under nano-Si (+10.51% vs. Cd). Bioavailable Cd declined significantly: Cd+nSi and Cd+nZn reduced it by 14.54% and 16.36%, respectively, and lowered the Cd transfer coefficient by 17.77% and 15.54%. (4) Nano-Si outperformed nano-Zn in suppressing Cd uptake and translocation. The bioconcentration factor decreased by 36.63% (Cd+nSi) and 31.08% (Cd+nZn), while the translocation factor dropped by 13.70% (Cd+nSi) and 2.72% (Cd+nZn) versus the Cd treatment. Overall, nano-fertilizers surpassed conventional fertilizers in mitigating Cd stress, with nano-Si demonstrating superior efficacy over nano-Zn in restricting Cd accumulation and transfer in rice.

The biological property by which plant root tips perceive moisture gradients and bend toward regions of higher water potential is termed hydrotropism. As a critical adaptive strategy for plants to respond to dynamic water environments, hydrotropism drives roots to actively navigate toward water sources, optimizing water acquisition. The regulatory mechanism of hydrotropism involves the coordinated mediation of second messengers (reactive oxygen species and calcium ions), phytohormones (abscisic acid, auxin and cytokinin), and key regulators such as MIZ1. Plants achieve adaptive responses to water stress through integrating processes of moisture gradient perception, signal transduction, and asymmetric hormone distribution. However, significant differences exist in hydrotropic regulatory mechanisms among species, and in the interactions with other tropisms (gravitropism, phototropism, and thigmotropism). Elucidating the core regulatory factors of hydrotropism and the interaction patterns of the signaling networks would provide a theoretical basis for genetic improvement of water-use efficiency in crops and sustainable agricultural development.

A controlled experiment was conducted using Wisteria sinensis seedlings inoculated with Funneliformis mosseae to investigate the effects and physiological mechanisms of arbuscular mycorrhizal fungi (AMF) on the Pb stress tolerance of W. sinensis seedlings. Pb contamination gradients were established (400, 800, 1200 mg/kg) to measure the growth parameters (growth, biomass, tolerance index) and physiological indicators (chlorophyll content, malondialdehyde content, proline content and related antioxidant enzyme activities). AM fungi inoculation significantly enhanced both aerial and root growth of W. sinensis seedlings while improving the Pb stress tolerance. The translocation factor and shoot bio-concentration factor were lower than those of the control, whereas the root bio-concentration factor exceeded the level of the control groups. This demonstrated that AM fungi effectively reduced Pb accumulation in the aerial parts while significantly enhancing Pb sequestration capacity in the roots. Physiological analysis indicated that AM fungi-treated seedlings exhibited higher chlorophyll content and elevated the activities of antioxidant enzymes (SOD, POD, APX), along with significantly lower MDA accumulation compared to the non-inoculated controls. Principal component analysis combined with cluster heat-map visualization further demonstrated that AM fungi primarily enhanced the Pb tolerance of W. sinensis through three mechanisms: activation of antioxidant enzyme systems, regulation of growth-related processes, and modulation of chlorophyll biosynthesis pathways. The results provide theoretical and practical basis for mycorrhizal plant remediation of heavy metal pollution.

This study investigated the population stability and productivity of ratoon sugarcane through inter-varietal replanting, aiming to provide agronomic insights for prolonging ratoon cycles and enhancing population stability and productivity through improved cultivation management. Using the second ratoon crop of sugarcane variety Guitang 42(GT) scheduled for replanting after mechanical harvest, replanting was done with the variety Guifu 98-296 (GF) seedcanes (termed inter-varietal replanting) in the place where the cropping row was broken because of missing sugarcane stubbles, with the same untreated ratoon crop as the control (CK). Emergence rate, ratoon sprouting rate, plant height, stalk formation rate, and cane yield in the first-year replanted GT ratoon sugarcane (R₁), R₁+newly planted GF (GF₀) (set the same CK as CK₁), second replanted ratoon (R₂), and R₂+first ratoon GF (GF₁) (set the same CK as CK₂) were evaluated. Economic benefits were analyzed across treatments. The results indicated that in the first year after replanting, the GF₀ exhibited a emergence rate of 88.61%, which was significantly higher than that of R₁ and CK₁. GF demonstrated markedly greater plant height increment compared to CK₁ and R₁ but no significant difference existed between CK₁ and R₁ between May and December. At the maturity stage, neither the stalk formation rate nor the cane yield differences showed statistically significant between CK₁ and R₁. However, the millable stalks in the sugarcane population (R₁+GF₀) significantly increased to 62 265 per hectare, resulting in extremely significantly higher cane yield with 24.60 tons per hectare or 35.34% increase over CK₁. In the second year, the sprouting rate of GF₁ reached 260.48%, which was extremely significantly higher than that in R₂ and CK₂. Its plant height difference between May and December was also extremely significantly greater than that of CK₂ and R₂, and there was no significant difference in that between CK₂ and R₂. At the maturity period, the stalk formation rate and cane yield in CK₂ and R₂ were both significantly lower than those in the previous ratoon crop, but the cane yield in the treatment R₂+GF₁ was extremely significantly higher than that in CK₂ by 4.62% with an increase rate of 161.75%. This indicated that the increased cane yield in variety mixed ratoon crop populations mainly came from GF. Economic benefit analysis showed that in the first year after replanting, sugarcane farmers and sugar factories increased their income by 8164.88 Yuan/hm² and 17 655.00 Yuan/hm², respectively. After replanting treatment, the difference in increased revenue between the first and second years for sugarcane farmers and sugar factories was approximately 2.98 times. Replanting the elite sugarcane variety GF to the ratoon cane of the main cultivated variety GT under mechanical harvesting conditions could effectively address the severe problem of missing plants and broken rows caused by mechanical compaction. This approach significantly increased the millable stalks in the sugarcane population, prolonged the ratoon duration by two more years, and showed a noticeable increase in cane yield and income. Therefore, the replanting technology system of GF is worth promoting in China’s sugarcane-growing areas.

Organic fertilizer can effectively improve soil fertility and microbial diversity, as well as metabolic activity, in facility cultivation. It can also alleviate problems such as water-heat imbalance, soil secondary salinization, acid-base imbalance, reduced microbial diversity, and insufficient nutrient supply in facility greenhouses. Currently, however, research on organic fertilizers mostly focuses on open fields and field crops, and most studies use animal manure as the organic fertilizer. This study selected Hainan coir organic fertilizer and bio-enzyme-active bacterial fertilizer as bottom fertilizers. High-throughput sequencing technology was used to study how different bottom fertilizers and their dosages affect soil nutrient and microbial changes in facility greenhouses. The goal was to identify effective fertilization methods for improving soil. The results showed that: (1) The application of 14 286 kg/hm² of coir organic fertilizer effectively improved soil pH, organic matter, total nitrogen, effective phosphorus, and quick-acting potassium. The bio-enzyme-activated bacterial fertilizer improved the soil's total nitrogen, effective phosphorus, and quick-acting potassium levels, but the effect was weaker than that of the coir organic fertilizer. The CK indicators were generally lower than the pre-planting levels. (2) The number of soil bacterial OTUs generally decreased after planting. However, organic fertilizer treatments, especially bioenzyme treatments, could partially restore or enhance microbial diversity. Coconut coir organic fertilizer was more conducive to the proliferation of beneficial bacterial flora, such as Rhizobiales and Paecilomyces spp. WSH L07. Bioenzyme-activated bacterial fertilizers had an effect on Sphingomonadales, Rhodospirillales, and Aspergillus terreus.

The study was aimed to evaluate the adaptability of new sugarcane varieties from the 2021 national regional trials in Kaiyuan and other sugarcane-growing regions of Yunnan, and to provide a scientific basis for the promotion in Yunnan and other ecologically similar sugarcane regions. 13 new sugarcane varieties from the 15^th round of the national sugarcane regional trials were used. Guiliu 05136 and Yunzhe 05-51 were used as the controls. The trial was carried out in Kaiyuan, Yunnan, with one year of plant and two years of ratoon crops. A comprehensive evaluation was conducted on 12 traits, including cane yield, sugar yield, early-stage average sucrose content, full-cycle average sucrose content, germination rate, ratoon tillering rate, tillering rate, plant height, stalk diameter, millable stalks, dead heart rate and smut incidence, using the DTOPSIS method. The results showed that the varieties ranked by the DTOPSIS analysis (C_i values) were as follows: Liucheng 1539>Yunzhe 15505>Zhongtang 1211>Guiliu 05136>Yunzhe 05-51>Guitang 13334>Zhongzhe No. 14>Zhongzhe No. 8>Guitang 14811>Funong 1311808>Guitang 161253>Funong 141854>Yuegan No.59>Guinan Ya 146210>Yunrui 14662. The top three varieties based on C_i values were Liucheng 1539 (0.7413), Yunzhe 15505 (0.6225) and Zhongtang 1211 (0.5975), all of which exhibited superior comprehensive traits and outperformed both controls. Liucheng 1539 had the highest cane yield (141 279.00 kg/hm²) and sugar yield (19 930.44 kg/hm²) among the tested varieties, with rapid early growth, good tillering, healthy leaves, strong vigor, good clumping and easy defoliation. It also showed low rates of dead hearts and smut incidence. Zhongtang 1211 had the highest number of millable stalks (107 226 stalk/hm²), rapid early growth, healthy leaves, high yield potential, and relatively high sucrose content and sugar yield, along with low rates of dead hearts, smut, and mosaic disease incidence. Yunzhe 15505 demonstrated the strongest disease resistance, with the lowest rates of dead hearts (2.29%) and smut incidence (0.14%), easy defoliation, lodging resistance, and relatively high sucrose content and sugar yield. Varieties Liucheng 1539, Yunzhe 15505, and Zhongtang 1211 exhibited significant advantages in early field performance, yield traits, and stress resistance, demonstrating excellent overall performance. They show great potential for large-scale promotion in Kaiyuan, Yunnan, and other ecologically similar areas.

The root system of Taraxacum kok-saghyz (short for TK) contains laticifers capable of producing natural rubber, and the structure and properties closely resemble the laticifers of rubber tree (Hevea brasiliensis). So,. Tk is recognized as an ideal alternative plant source for natural rubber production. Due to morphological disparities between Hevea and Taraxacum, conventional iodine-bromine (I₂Br₂) staining proves unsuitable for laticifers morphological studies in T. kok-saghyz. Furthermore, bromine (Br₂), the primary component of traditional I₂Br₂ staining solution, is classified as a Category II precursor chemical under stringent regulatory controls owing to its potent corrosivity, irritancy, and high procurement/transportation costs. To develop safer and more economical staining protocols for laticifer morphology, this study substituted Br₂ with sodium bromide (NaBr) and hydrogen bromide (HBr). Light microscopic analysis of root sections stained with various NaBr/HBr-I₂ formulations revealed I₂Br₂ staining induced light tan coloration of latex in laticifer, but caused severe structural degradation, and yielding suboptimal staining and section quality, NaBr-based formulation (1 mol/L NaBr+0.2 mol/L I₂ in acetic acid) demonstrated improved staining efficacy with preserved root morphology, HBr-based formulation (2.5 mmol/L HBr+0.2 mol/L I₂ in acetic acid) achieved optimal staining intensity while maintaining perfect histological integrity, and aqueous solvent systems (NaBr/HBr+I₂ in H₂O) failed to stain laticifers and induced significant tissue damage. The results confirmed that NaBr and HBr could serve as safer, cost-effective alternatives to Br₂ for laticifer morphological studies. The developed methodologies would provide critical technical foundations for investigating laticifers in non-woody rubber-producing plants, including T. kok-saghyz, Lactuca species, etc.

Transcriptional regulation is one of the pivotal mechanisms governing biological activities. Natural rubber (NR), a crucial industrial raw material, is predominantly derived from rubber trees. The transcriptional regulation of NR biosynthesis has emerged as a focal point in the fundamental research of rubber tree in recent years. Mevalonate diphosphate decarboxylase (MVD) is a key enzyme in the biosynthetic pathway of NR, yet its transcriptional regulation remains poorly understood. In this study, a 1500 bp promoter region of the HbMVD1 gene from rubber tree was cloned. Sequence analysis revealed the presence of various cis-acting elements, including the responsive to jasmonic acid, ethylene, mechanical wounding, light, and MYC binding. A gradient assay for autoactivation suppression demonstrated that the transcriptional autoactivation of the pAbAi-pHbMVD1 bait vector was effectively inhibited at an AbA concentration of 100 ng/mL. 13 non-redundant proteins from a rubber tree latex yeast cDNA library that interact with the HbMVD1 promoter, including one WRKY transcription factor (HbWRKY1), one heat shock transcription factor, and one G-box binding factor were identified utilizing yeast one-hybrid screening. Tissue-specific expression analysis indicated that the genes encoding the proteins exhibited distinct expression patterns across different tissues. Transcriptional regulation analysis showed that HbWRKY1 activated the expression of HbMVD1 in vivo. Molecular docking revealed that HbWRKY1 bound to the mechanical wounding element of the HbMVD1 promoter, and 11 potential amino acid binding sites were identified. This study would lay the groundwork for further elucidating the transcriptional regulatory network of HbMVD1 in rubber tree.

It was aimed to screen drought-resistant pepper varieties and clarify the correlation between drought resistance at the seedling stage and key morphological and biochemical indicators. Eight pepper inbred lines were selected for the study. The experiment adopted a pot-based natural drought treatment method, and the drought resistance of the lines was ranked using the membership function value analysis method. The order of drought resistance was as follows:4-1>163-2 UP>112 D>10-2 UP>134 UP>34>158 D>115 D. Through correlation analysis between drought resistance at the seedling stage and key morphological and biochemical indicators, it was found that the order of correlation between morphological indicators and seedling drought resistance was aboveground-to-underground area ratio>aboveground area>root system area>leaf area>main root length, aboveground to-underground area ratio showed a significant negative correlation with drought resistance at the seedling stage, with a correlation coefficient of -0.625. The order of correlation between biochemical indicators and seedling drought resistance was peroxidase (POD)>proline (PRO)> malondialdehyde (MDA)>superoxide dismutase (SOD), peroxidase and proline exhibit significant correlations with drought resistance at the seedling stage, with correlation coefficients of 0.675 and -0.638, respectively. The results would lay a foundation for gradually improving the establishment of a drought resistance screening system for peppers and further enable the large-scale screening of resistant pepper varieties using phenomics, and provide new insights for breeding drought-resistant pepper varieties and hold significant importance for promoting the sustainable development of the pepper industry.