The study investigated the effects of different exogenous hormones on somatic embryo maturation to improve the maturation efficiency of somatic embryos and increase the yield of normal mature embryos and embryo-derived plantlets in the rubber tree variety Yunyan 73-477. Primary somatic embryos from anthers at different developmental stages were cultured on media supplemented with various types and concentrations of exogenous hormones. The maturation rates, normal mature embryo rates, and plantlet conversion rates were comprehensively analyzed to compare maturation efficiencies and optimize hormone combinations for different developmental stages. The maturation efficiency increased with embryo developmental progression, with cotyledon embryos showing optimal results. The maturation rates exceeded 50% [range: 50.74%-74.83%, mean: (66.25±6.98)%]. Most mature embryos displayed bipolar structure and could normally germinate into complete plantlets, with normal mature embryo rates ranging from 35.0%-59.96% [mean: (47.80±6.89)%] and plantlet conversion rates ranging from 15.62%-49.17% [mean: (26.67±8.99)%]. Torpedo-shaped embryos showed intermediate performance, while heart-shaped embryos performed the poorest, both with maturation rates below 31% [means: (30.05±12.68)% and (29.33±10.93)%, respectively]. Most mature embryos from the stages were malformed (leaf-like or callus-like) and failed to develop into complete plantlets. The normal mature embryo rates were only (15.64±7.01)% and (5.46±4.28)%, respectively, 32.16% and 42.34% lower than cotyledon embryos. Plantlet conversion rates were (7.22±3.41)% and (0.83±0.80)%, merely 0.27-fold and 0.03-fold of cotyledon embryos. Optimal exogenous hormones varied with developmental stages: heart-shaped embryos required 6-BA 0.5 mg/L+NAA 0.15 mg/L+KT 0.25 mg/L, torpedo-shaped embryos needed ABA 0.4 mg/L+GA₃ 0.5 mg/L+6-BA 2.0 mg/L+NAA 0.15 mg/L, and cotyledon embryos performed best with ABA 0.1 mg/L+GA₃ 1.0 mg/L+6-BA 1.5 mg/L+NAA 0.2 mg/L.

The axillary buds, which are embedded in the stem of Phalaenopsis and lurked at the base of leaves, can germinate and elongate to form pedicels under suitable conditions. The microscopic observation of the differentiation process is one of the important research contents to understand the flower development process and influencing factors of Phalaenopsis. In order to establish a paraffin section method for two different tissues with soft and hard connection, the stem segment with axillary bud was used as the test material. The preparation steps, such as fixed time, softening liquid concentration and softening time, dehydration, etc., which mainly affect the paraffin section effect, were optimized. The results showed that vacuuming the fixative and extending the fixative time to 48 h or more were conducive to the full penetration of the fixative, and the fixative effect was the best. Using 10%, 12% hydrofluoric acid solution to soften for 12, 15 days and vacuuming for 30 min during softening could greatly reduce the brittleness and hardness of stem tissues with high lignification degree, meet the soft and hard requirements of sections, and effectively solve the problem of tissue separation and fragmentation caused by uneven softening. Dehydration treatment was set up with 7 step by step dehydration gradients from 30% to 100% ethanol, and the gradual replacement steps of anhydrous ethanol to xylene were added, which could avoid the shrinkage and deformation of tissue materials of Phalaenopsis and ensure the integrity of tissue morphology. The optimized preparation method avoids the problems such as incomplete softening, separation of tissues from paraffin wax, crumpling and crushing of wax bands, and cavity of sections caused by conventional preparation of the stem segment of the axillary bud of Phalaenopsis girdle, etc. The overall structure of the obtained sections tends to be complete, the staining is uniform and bright, and the tissue cells in each part are obviously colored. Young bud tissue and lignified stem tissue can be clearly distinguished. In this study, a set of paraffin section preparation method was developed which could be applied to the stem segment of Phalaenopsis axillary bud, a soft and hard tissue material, and would provide a technical basis for further study on the differentiation process of latent axillary bud germination of Phalaenopsis.

Diversity, correlation, cluster analysis and principal component analysis were condunted on 16 quantitative traits and 13 qualitative traits of 124 germplasm resources of Abelmoschus esculentus to clarify the genetic diversity and phenotypic traits of A. esculentus germplasm resources, and to provide a reference basis for the identification, evaluation, and innovative utilization of A. esculentus resources. The coefficient of variation of the 16 quantitative traits ranged from 8.2% to 59.8%, with an average coefficient of variation of 18.7%. The genetic diversity index ranged from 1.51 to 2.07, with an average of 1.94. The diversity index of qualitative traits ranged from 0.08 to 1.52. The diversity of fruit color, leaf color and leaf margin morphology was relatively high, while traits such as petal color and sepal retention were highly conservative. Correlation analysis showed that there was a close synergistic relationship among the leaf morphology (such as leaf length and leaf width), plant structure (such as plant height and plant width) and fruit characteristics (such as fruit longitudinal diameter and weight) of A. esculentus, while there was an antagonistic relationship among yield-related traits (number of fruits per plant and number of seeds). Principal component analysis simplified the 16 quantitative traits into 4 principal components, with a cumulative contribution rate of 99.25%. The contribution rate of the first principal component was 96.17%, indicating that plant height, plant width, commercial fruit length, commercial fruit width, fruit weight, and seed number per fruit had the greatest impact on phenotypic diversity. Based on the cluster analysis of Euclidean distance, the germplasm resources of A. esculentus were divided into four major groups. Group Ⅰ accounted for 70.16% of the resources and was mainly characterized by early maturity (short flowering period), low flowering node, short plant height, small plant width, and a high number of fruits per plant. This group was suitable for breeding new varieties with early maturity, high yield, and dense planting. Group Ⅱ accounted for 25.81% of the resources and was characterized by larger fruits, heavier single fruit weight, and larger leaves, which could be used for breeding mid-season varieties. Group Ⅲ and Group Ⅳ were primarily characterized by late maturity, taller plant height, larger leaves, and higher biomass yield, making them suitable for breeding feed-purpose varieties. Through quantitative and qualitative trait analyses of genetic diversity in okra germplasm resources, as well as principal component analysis and cluster analysis, the genetic variation, correlations, and genetic diversity relationships among various traits were elucidated. This study identified traits associated with early maturity and high yield, laying a foundation for the conservation and efficient utilization of okra germplasm resources, as well as for breeding new early-maturing and high-yielding varieties.

The growth of fruit trees inevitably casts a certain degree of shade on the grass plants in the orchard. Therefore, the selected grass species usually need to possess a certain level of shade tolerance. This study investigated the shade tolerance of two prevalent ground cover species in southern China, Alysicarpus bupleurifolius (L.) DC. and Alysicarpus vaginalis (L.) DC.. Different shading treatments were set with full light as the control (CK). Growth and physiological indices of the two species were measured, and a comprehensive evaluation of the shade tolerance was conducted to assess the potential as ground cover species in orchards. Findings indicated that as shading intensified, both species exhibited an overall increase in the leaf width, leaf area plant height and the proportion of aboveground biomass, while the stem diameter and total biomass showed a downward trend. Compared with A. vaginalis, the leaf area of A. bupleurifolius increased faster after 21 days of shading treatment, and the total biomass decreased less after 42 days of shading treatment. After shading treatment, the PSII maximum photochemical quantum yield (Fv/Fm) of the two plants was higher than 0.80, and shading did not cause serious damage to the photosynthetic system of the two plants. The relative electrical conductivity and malondialdehyde content of the leaves of the two species generally rose with increased shading intensity, whereas the peroxidase activity (POD) activity under shading conditions displayed distinct patterns. With the increase of shading intensity, the POD activity of A. bupleurifolius increased first and then decreased, while that of A. vaginalis showed a downward trend. Principal Component Analysis (PCA) was performed to reduce the dimensionality of 14 shade tolerance indices into two principal components, which cumulatively accounted for 88.66% of the total variance. In the first principal component (PC1), the contribution rate of malondialdehyde (MDA) content was the highest. In the second principal component (PC2), the contribution rate of leaf relative conductivity was the highest. The results of comprehensive evaluation of shade tolerance by membership function method showed that A. bupleurifolius was higher than that of A. vaginalis under identical shading conditions, indicating that the shade tolerance of A. bupleurifolius was higher than that of A. vaginalis. In summary, both A. bupleurifolius and A. vaginalis exhibit noticeable shade tolerance, with A. bupleurifolius outperforming A. vaginalis, thereby affirming the potential as viable orchard ground cover species.

Crotalaria pallida is an annual diploid self-pollinating plant of the genus Crotalaria in the Fabaceae family. It was described and published by WILLIAM TOWNSEND in 1789. Geographical studies believe that the species originated in the southeastern part of the Africa continent and Madagascar. Biologically, the species have the characteristics of high seed yield, wide adaptability, and fast growth, which makes it widely spread and distributed in tropical and subtropical regions around the world. The wide distribution has attracted the attention of ethnobotany and natural science research. It is generally believed that it is an important agricultural plant resource with great development potential in feed development, soil ecological restoration, and medicinal development. However, the utilization of C. pallida has always relied on wild resources, and research on accurate evaluation of germplasm resources, mining of genetic diversity, and breeding of excellent varieties is limited. This article reviews the research progress in the global distribution, biological learning, cultivation technology, feed value evaluation, soil nutrient maintenance, and medicinal value evaluation of C. pallida, and summarizes the current problems and future research directions, aiming to provide an important reference for promoting the research on the utilization.

The effects of spraying different combinations of plant growth regulators and foliar fertilizers at the appropriate fruit-setting time on the fruit expansion and quality of seedless fruits of Tainong No.1 mango were studied to provide a scientific basis for the high-quality and high-yield cultivation techniques of seedless fruits of Tainong No.1 mango, and to offer a reference for the scientific application of fertilizers for the expansion of seedless fruits of other small-and medium-sized mangoes. From 2022 to 2024, the seedless fruits of Tainong No.1 mango were used and four foliar spraying treatment schemes were set up, the control group (CK) with foliar fertilizer, T₁ treatment with gibberellic acid + foliar fertilizer, T₂ treatment with gibberellic acid + plant growth regulator + foliar fertilizer, and T₃ treatment with compound plant growth regulator product + foliar fertilizer. The growth and development and fruit quality indicators of the seedless fruits were measured and analyzed. The results showed that when the fruits were 6-10 mm in size, spraying gibberellic acid + plant growth regulator + foliar fertilizer four times, the single-fruit weight of green fruits in T₁ and T₃ treatments was greater than 100 g, while the average single-fruit weight of green fruits in CK was 67.55 g, and the fruit-expanding effect was obvious. Among them, the average single-fruit weight of green fruits in T₃ treatment increased by 98.98% compared with CK. T₁ and T₃ treatments significantly increased the calcium content. T₁ and T₃ treatments significantly decreased the average density, weight loss rate, total acid content, and vitamin C content of green fruits. T₁ and T₃ treatments had no significant effect on the fruit shape index. T₂ treatment significantly decreased the soluble solid content, while T₁ and T₃ treatments had no significant effect on the soluble solid content. T₁ and T₃ treatments significantly increased the solid-acid ratio. Among them, T₁ treatment significantly increased the solid-acid ratio, which was 45.34% higher than CK, and T₂ treatment had no significant effect on the solid-acid ratio. T₁ and T₃ treatments significantly increased the magnesium content, while T₂ treatment had no significant effect on the magnesium content. T₁ and T₂ treatments significantly decreased the potassium content, while T₃ treatment had no significant effect on the potassium content. No residues of the used plant growth regulators were detected in the fruits. 1 mango in each treatment. Comprehensive score of the fruit quality of the fruits revealed the fruit quality of T₁ treatment was the best, followed by T₃ treatment. However, the single-fruit weight of T₁ treatment after full ripening was less than 100 g, which could not fully meet the market's requirement for single-fruit weight. The fertilizer combination of T₃ treatment is recommended for the production of seedless fruits of Tainong No.1 mango.

Sugarcane is a crucial crop for both sugar and bioenergy production, with sugar accumulation and cell wall formation being critical biological processes during its growth and development. This study employed transcriptome sequencing on the ROC22 sugarcane variety, collecting samples from leaves at the 1^st, 3^rd, and 5^th nodes, bark tissues at the 3^rd, 5^th, 7^th, 11^th, and 17^th internodes, and pith tissues at the 1^st, 3^rd, 5^th, 7^th, 11^th, and 17^th internodes. A comprehensive analysis of 42 transcriptome datasets using Weighted Gene Co-expression Network Analysis (WGCNA) revealed 34 distinct co-expression modules. Notably, the midnight blue, purple, and magenta modules demonstrated significant and specific correlations with the 1^st node leaf, 7^th internode pith, and 5^th internode bark, respectively. KEGG and GO enrichment analyses indicated that the modules participated in tissue-specific biological processes. The blue, yellow, turquoise, and black modules were primarily expressed in leaves, young pith, immature internodes, and bark, respectively. Within the blue module, key enzymes implicated in photosynthesis were identified, such as LFNR1, PSAK, PETE, PSAN, and NADP-ME4, which are essential for the initial production and accumulation of sugar in sugarcane. The yellow module featured a sucrose metabolism network centered on SUS4, including SWEET2 and an array of sugar transport-related enzymes and proteins, suggesting that the pith serves as the primary site for sugar transport and storage in sugarcane. The turquoise module contained glycoproteins and enzymes potentially involved in the synthesis and modification of the primary cell wall. Meanwhile, transcription factor NST1, which regulates secondary cell wall biosynthesis, along with other cell wall-modifying enzymes in the black module, may contribute to cell wall deposition in the cortex, providing mechanical strength and a barrier against external stresses for sugarcane. The findings would provide important references for studying the regulatory networks of sugar accumulation and cell wall formation in sugarcane.

Sugarcane (Saccharum hybrids spp.) is an important sugar crop and cash crop in Guangxi. Revealing the characteristics of sugarcane nutrient requirements is an important foundation for promoting high yield, high quality and efficient cultivation of sugarcane. In recent years, the selection and application of new sugarcane varieties in China have been rapid. A field experiment was conducted in the main sugarcane producing areas of Guangxi on red upland soil to promote the efficient cultivation of new sugarcane varieties. The dry matter accumulation, nutrient accumulation, and nutrient efficiency of GT44, GT49, GT55, GT58 and YT00-236 in both plant and ratoon crops were analyzed. The results showed that the dry matter accumulation in the 2^nd ratoon crop of the five varieties was significantly higher than that in the plant and 1^st ratoon crops. The accumulated amount of stalk dry matter and whole crop dry matter in three crops were the highest in GT58, reaching 66 946 kg/hm² and 96 785 kg/hm², respectively, which was 6.48%-19.01% and 2.57%-25.06% more than that in the other varieties, followed by YT 00-236, and the least in GT 49. The accumulation of N, P and K in the 2^nd ratoon crop was significantly higher than that in the plant and 1^st ratoon crops for all the varieties. In different crops, the accumulation of N, P and K in the five varieties was 99.81-212.18, 11.04-27.01, 150.09-400.29 kg/hm², respectively. The accumulated amount of N, P and K in the three crops was the highest in GT58, which increased by 5.16%-20.75%, 4.38%-31.85% and 6.29%-21.45%, respectively, compared with the other varieties, and that in GT49 was the lowest. The N, P, K requirement of a ton cane in different crops for the five varieties was 1.66-2.59, 0.19-0.30 and 2.76-3.76 kg, respectively, but GT44 and GT55 had more requirements while GT49 had less requirements. The economic efficiency of nitrogen, phosphorus and potassium in the three crops was higher in GT49, and the physiological efficiency of nitrogen, phosphorus and potassium was higher in YT00-236. In conclusion, the biological production of GT58 is better, and the nutrient efficiency of GT49 and YT0026 is higher.

The application of exogenous trace elements can help improve the yield and quality of certain economic crops. However, the effects of exogenous zinc on the photosynthetic physiological characteristics and volatile compounds in Pandanus amaryllifolius Roxb. (Pandan) remain unclear. Therefore, this study established a field control experiment on Pandan leaves with different zinc spray treatments, 0 kg/hm² (CK), 3.2 kg/hm² (Zn₁), 4.0 kg/hm² (Zn₂), and 4.8 kg/hm² (Zn₃). The aim was to monitor the temporal and spatial dynamics of the photosynthetic rate and volatile compounds content following zinc fertilization. The results indicated that Zn₂ treatment significantly increased the chlorophyll content, promoted the leaf growth and development, and resulted in the highest leaf count at all stages post-treatment. However, prolonged high-concentration zinc fertilization could inhibit leaf expansion and plant height. The photosynthetic physiology, photosynthetic rate, stomatal conductance, and transpiration rate increased with zinc concentration. Around 30 days post-treatment, Zn₃ treatment performed the best, followed by Zn₂ treatment. Zinc fertilization increased the content of volatile compounds. Zn₂ and Zn₃ treatments were notably effective in promoting the synthesis of several volatile compounds, such as 2-acetyl-1-pyrroline, 2-hexadecanol, and ethyl palmitate. Under Zn₂ treatment, the content of 2-acetyl-1-pyrroline and 2-hexadecanol increased by 203% and 80.89%, respectively, compared with CK. Zn1 treatment significantly increased 2-acetyl-1-pyrroline content at 20 days post-application, while Zn₃ treatment significantly promoted the synthesis of squalene, neophytadiene, and phytol. Correlation analysis showed that the main volatile compounds in Pandan interacted with agronomic traits and photosynthetic physiological indicators. The increase in photosynthetic rate and leaf count promoted the synthesis of squalene and neophytadiene, whereas elevated intercellular CO₂ concentration might inhibit the accumulation of 2-acetyl-1-pyrroline and squalene. This study demonstrates that appropriate zinc fertilization can effectively enhance photosynthesis, increase chlorophyll content, promote leaf growth, and boost the content of volatile compounds and characteristic volatile compounds in Pandan. The findings would provide a theoretical basis for optimizing high-efficiency cultivation techniques for Pandan and promoting the sustainable development of Pandan-related industries.

The response of nitrogen, phosphorus and potassium nutrient accumulation, yield and output value of flue-cured tobacco in multi-planting area of tobacco-rice to the nitrogen application and basal-topdressing ratio was studied to provide a theoretical basis for the development of fertilizer application strategies for paddy-tobacco. Cultivar Yunyan 87 was used and three nitrogen application treatments (150 kg/hm², 165 kg/hm² and 180 kg/hm²) and two basal-topdressing ratio of nitrogen treatments (3∶7 and 5∶5) were set up. The effects of nitrogen application and basal-topdressing ratio on the accumulation and distribution of nitrogen, phosphorus and potassium nutrients, also on yield, output value and fertilizer utilization of paddy-tobacco, and the contribution rate of nitrogen application and basal-topdressing ratio and the interaction to the accumulation of nitrogen, phosphorus and potassium were analysed using the effect value (). The results showed that nitrogen, phosphorus and potassium nutrients accumulated by flue-cured tobacco were mainly allocated to tobacco leaves, and the proportion allocated to tobacco leaves decreased with the growth of flue-cured tobacco. With the increase of nitrogen application, nitrogen accumulation and tobacco yield and output value of flue-cured tobacco increased, meanwhile reducing the proportion of base fertilizer nitrogen could significantly increase the nitrogen accumulation of the tobacco plant and yield and output value of tobacco leaf, also significantly increase the utilization rate of nitrogen fertilizer and the partial productivity and the partial production benefit of nitrogen, phosphorus and potassium fertilizers. On average, nitrogen application and basal-topdressing ratio and the interactions contributed 42.89%, 29.63% and 27.47% to nitrogen accumulation of flue-cured tobacco, and 38.62%, 24.12% and 37.25% to phosphorus accumulation, and 41.22%, 21.24% and 37.54% to potassium accumulation, and 62.13%, 6.34% and 31.53% to yield, and 47.30%, 14.74% and 37.95% to output. Throughout the reproductive period, nitrogen accumulation was relatively high in the nitrogen treatments of 180 kg/hm² and the 3∶7 basal-topdressing N ratio. In the rosette stage and dome stage, the accumulation of phosphorus and potassium was relatively high in the nitrogen treatments of 180 kg/hm² and 3∶7 basal-topdressing N ratio. The highest yield and output value were achieved in the nitrogen treatments of 180 kg/hm² and 3∶7 basal-topdressing N ratio. Therefore, in the multi-planting area of tobacco-rice, the nitrogen application has the greatest influence on the accumulation of nitrogen, phosphorus and potassium nutrients in flue-cured tobacco, and the reduction of the proportion of base fertilizer nitrogen from 50% to 30% can increase the accumulation of nitrogen of tobacco leaf, which is conducive to the improvement of the yield and output value of tobacco leaf and the utilization rate of nitrogen fertilizer.