Search Results (60)

The provincial-level registered superior cultivar Camellia chekiangoleosa ‘Ganhongyou 1’ boasts superior economic traits coupled with significant ornamental value, driving demand for an efficient propagation system. Consequently, this study aimed to develop a rapid micropropagation protocol by investigating culture conditions using semi-woody nodal segments with axillary buds as explants on Hyponex basal medium supplemented with varying combinations of plant growth regulators. Contamination was effectively minimized to 18% by a combined approach of surface sterilization (75% ethanol, 0.1% HgCl₂, and 20% NaClO) and incorporating 1 mL/L bactericide into the induction medium. For bud induction, the optimal medium was 2 g/L Hyponex supplemented with 1.0 mg/L 6-benzylaminopurine (6-BA) and 0.2 mg/L indole-3-acetic acid (IAA), achieving an 86.67% induction rate. The best proliferation was achieved on the medium containing 2 g/L Hyponex, 1.0 mg/L 6-BA, 0.15 mg/L 3-indolebutyric acid (IBA), and 0.5 mg/L gibberellic acid (GA₃), yielding a proliferation coefficient of 6.53. A combined strategy, integrating in vitro pre-culture with ex vitro treatment, proved most effective for rooting and acclimatization: shoots were first pre-cultured for 20 days on 1/2 strength Hyponex medium supplemented with 0.5 mg/L 1-naphthaleneacetic acid (NAA) and 2.0 mg/L IBA, followed by ex vitro base treatment with 1.0 g/L ABT (a rooting powder complex) solution before transplantation into seedling bags. This approach resulted in an 88% survival rate. Furthermore, anatomical analysis revealed the origin of adventitious root primordia from phloem parenchyma cells, thereby confirming a phloem-rooting pattern for this species. In conclusion, this study establishes a practical and efficient micropropagation protocol for ‘Ganhongyou 1’, providing a reliable technical foundation for its commercial-scale seedling production. Full article

Shoot tip culture is currently the most widely used method for strawberry virus elimination, yet its efficiency has approached the theoretical limit of 80–85%. While anther culture offers a higher virus-free rate, it faces the technical bottleneck of low callus differentiation rates. To address this issue, this study used ‘Miaoxiang 7’ strawberry anthers as explants and systematically optimized key culture parameters. Different combinations of cytokinins and auxins were tested across various culture stages—including callus induction, adventitious bud differentiation from callus, proliferation, and rooting—to determine the most efficient plant growth regulator (PGR) formulations. This approach enhanced both the callus induction rate and differentiation efficiency. The regenerated plants obtained in this study achieved a virus-free rate of 98.39%. Flow cytometric ploidy analysis revealed that octoploids constituted the highest proportion, reaching 73.64%, among the regenerated plants. SSR molecular marker analysis indicated a genetic similarity coefficient of 0.9778–1.0000 between the regenerated plants and the maternal parent. Virus-free treatment holds potential for enhancing physiological growth indicators and fruit quality, demonstrating advantages in certain key metrics such as leaf area and soluble solids content. This technological system provides a viable approach for obtaining virus-free plants through anther culture, overcoming the technical limitation of low callus differentiation rates in anther culture. It offers reliable technical support for the sustainable development of the strawberry industry. Full article

Global warming leads to premature dormancy release and untimely flowering in southern highbush blueberry during winter, resulting in chilling injury and yield losses. However, effective strategies to delay flowering by modulating dormancy progression without compromising fruit quality remain lacking. This study demonstrated through field trials that spraying 1 mg/mL ethephon (ETH) during the early endodormancy stage effectively delayed dormancy release and reduced the bud break rate of spring shoots by approximately 33.92% relative to the control, with no adverse effects on fruit quality. The treatment also reduces sucrose content in floral buds, a change potentially associated with dormancy maintenance. To explore the molecular basis of this process, we examined two ethylene-responsive transcription factors, VcERF112 and VcERF115, previously identified in our laboratory. Their expression was rapidly upregulated following ETH treatment. Heterologous expression of either gene in Arabidopsis delayed both seed germination and flowering, suggesting a conserved growth-suppressive function. Dual-luciferase reporter assays confirmed that VcERF112 and VcERF115 bind to the T2 region (−2310 to −1595 bp) of the VcBRC1 (VcBRANCHED1) promoter and enhance its expression. In contrast, sucrose treatment suppressed VcBRC1 expression. Collectively, these results propose that ethylene may sustain bud dormancy through a coordinated mechanism that operates independently of the classic abscisic acid (ABA)/gibberellins (GA) balance, a relationship not addressed in this study. This mechanism involves the induction of VcERF112/115 to activate VcBRC1, coupled with the reduction in sucrose levels to alleviate its repressive effect on VcBRC1. These findings provide new molecular insights into the ethylene-mediated regulatory network underlying bud dormancy in blueberry. Full article

Ficus carica L. is a fruit crop of notable nutritional and economic value. The ‘Xinjiang Zaohuang’ cultivar, rich in flavonoids, also holds considerable medicinal potential. To address the constraints of conventional propagation for mass production, this study developed an efficient and genetically stable generation protocol using healthy sprouted branches. MS medium was identified as the most effective basal medium for shoot growth. The highest adventitious bud induction rate (89.67%) and the greatest mean bud number (6.29) were achieved when explants were cultured on MS medium supplemented with 1 mg/L 6-BA and 0.1 mg/L IBA. In the organogenesis process, indole-3-butyric acid (IBA) promoted direct shoot formation with minimal callus intervention compared to naphthaleneacetic acid (NAA). The optimal combination for shoot elongation was 0.1 mg/L 6-BA and 0.01 mg/L IBA, which produced morphologically uniform shoots. For rooting, an IBA concentration of 1 mg/L was optimal, achieving a 96.7% success rate. Inter-simple sequence repeat (ISSR) analysis confirmed the genetic stability of all regenerated plants. These findings establish a reliable technical framework for the large-scale propagation of this valuable fig cultivar. Full article

Floral induction in late-maturing litchi is vulnerable to warm, humid winters with insufficient chilling. The late cultivar ‘Ziniangxi’ was evaluated during January–February 2024 in an experimental orchard in Hainan, China, when chilling accumulation was very low, with only seven days having a mean air temperature ≤ 15 °C. Under this marginal-chill context, the effects of plant growth regulator (PGR) applications on bud fate were assessed using six single-agent and thirteen composite PGR–nutrient treatments plus a water control, applied as four foliar sprays during floral induction. In the untreated control, the final flowering proportion of tagged shoots was 0.33 in the single-agent trial and 0.05 in the composite trial. In contrast, ABA (3.33 mg L⁻¹) increased flowering to 0.53, and ethephon- or brassinolide-based applications to 0.40–0.47. The most effective composite formulations raised flowering further to 0.50–0.63. These composite applications also increased leaf starch from about 4 mg g⁻¹ FW in the control to approximately 8–9 mg g⁻¹ FW ($p<0.05$), whereas sucrose concentrations showed only small differences among treatments. Across trials, shoots that became floral consistently exhibited higher leaf starch than vegetative shoots. Gene-expression analyses indicated that floral buds had higher transcript abundance of LcFUL and lower transcript levels of LcFLC and other floral repressors than vegetative buds, consistent with their assignment to floral versus vegetative categories. Overall, the results suggest that appropriately timed ethephon–ABA-based PGR programs, supplemented with BR or 6-BA and nutrients, can partially improve floral induction in ‘Ziniangxi’ under warm, low-chill winters and provide a basis for designing PGR strategies for late litchi cultivars facing insufficient winter chilling. Full article

In this study, Hedychium coccineum tetraploid plants and octaploid plants induced by colchicine were used as materials. The ploidy levels were precisely identified by combining root tip squash and flow cytometry analyses, and the differences between plants of different ploidy levels were systematically investigated at cytological, morphological, and molecular levels. The results showed that the highest polyploid induction efficiency was achieved when callus tissues were treated with 0.1 g/L colchicine for 4 days. The fluorescence peak value of the induced plants was twice that of the tetraploids, confirming their octaploid status. Compared with tetraploids, octaploid plants exhibited almost no apparent dormancy period, significantly slower growth, earlier flowering, and notably smaller inflorescences. Morphologically, they showed a dwarf phenotype characterized by narrower and lighter-colored leaves, fewer leaves per shoot, shorter internodes, and wider leaf angles, along with enhanced stress tolerance. Cytological observation revealed that cell area in internode tissues at the bud and seedling stages was generally larger in tetraploids than in octaploids, suggesting a reduction in cell size following genome duplication. Furthermore, transcriptome comparison between tetraploids and octaploids identified HcPCNA1 as a candidate gene closely associated with plant height. Functional validation showed that overexpression of HcPCNA1 in Arabidopsis thaliana significantly increased plant height, whereas silencing of HcPCNA1 in H. coccineum via Virus-induced gene silencing (VIGS) resulted in a distinct dwarf phenotype with smaller leaves. Cytological and molecular evidence together indicate that HcPCNA1 may influence plant height in H. coccineum through its role in promoting cell division and elongation. This finding provides new insights into the molecular mechanisms underlying plant architecture development in polyploid species. Full article

This study established an efficient in vitro regeneration system using stem nodes from root collar suckers as explants. Subsequently, regenerated shoots were used to establish an in vitro medicinal production protocol that achieved ginkgolic acid production. The self-developed Ginkgo biloba medium (GBM), first reported in this study, was pivotal to system establishment. The plantlet propagation system showed that the bases of stem nodes dipped in GBM with 2 mg·L⁻¹ 6-benzyladenine (BA) and 0.2 mg·L⁻¹ 1-naphthaleneacetic acid (NAA) achieved near-complete axillary bud induction (99.56%). Adventitious shoot induction reached 82.22% (3.5 shoots/explant) using GBM with 0.2 mg·L⁻¹ BA, 0.02 mg·L⁻¹ kinetin (Kin) and 0.2 g·L⁻¹ proline (Pro). Maximum adventitious shoot elongation (92.22%, average 3.35 cm) was observed on GBM containing 0.1 mg·L⁻¹ zeatin (ZT) and 0.01 mg·L⁻¹ BA. After 3-week preculture with 15 mg·L⁻¹ phloroglucinol (PG), treatment with 0.6 mg·L⁻¹ indole-3-butyric acid (IBA) and 0.2% activated carbon (AC) yielded 96.67% rooting (6.19 roots/explant) and 85% acclimatization survival. For medicinal resource production, bud cluster induction at 94.44% (20.89 buds/explant) on GBM with 1 mg·L⁻¹ BA, 0.03 mg·L⁻¹ Kin, and 0.2 g·L⁻¹ Pro. Leaf organs in GBM with 0.3 mg·L⁻¹ BA, 0.01 mg·L⁻¹ Kin, 0.01 mg·L⁻¹ IBA, 0.3 g·L⁻¹ Pro, and 0.01 mg·L⁻¹ glutamine (Gln) accumulated 20.64 g fresh weight and 41.910 mg·g⁻¹ DW ginkgolic acids, representing a 4.93-fold increase over mother plants. This system enables large-scale Ginkgo biloba L. propagation and provides an in vitro strategy for producing medicinal compounds in endangered plants. Full article

9-cis-epoxycarotenoid dioxygenases (NCEDs), serving as the rate-limiting enzymes in abscisic acid (ABA) biosynthesis, play a pivotal role in regulating plant growth and development, as well as responses to abiotic stresses. Despite their agronomic importance, the molecular dialog between ABA signaling and vernalization, a cold-induced switch from vegetative to reproductive growth in wheat, remains poorly characterized, particularly regarding the TaNCED gene family members. Here, we systematically identified 13 TaNCED members in hexaploid wheat, followed by multi-omics characterization encompassing physicochemical properties, exon–intron architectures, conserved catalytic domains, protein motifs, and cis-acting elements. By analyzing transcriptome data from vernalization treatments, we profiled the expression patterns of TaNCED genes during vernalization. Notably, TaNCED5-6A, TaNCED5-6B, and TaNCED5-6D exhibited significant upregulation in vernalized leaves and tiller buds, while maintaining basal expression in the shoot apical meristem, the site of floral induction. This tissue-specific expression pattern implicates their specialized role in mediating vernalization responses via ABA biosynthesis. Collectively, our findings provide novel insights into the regulatory mechanisms of ABA-mediated vernalization in wheat and offer valuable targets for vernalization efficiency in cereal breeding programs. Full article

Catalpa bungei C.A.Mey is an economically significant deciduous tree valued for timber production and landscaping applications. An efficient regeneration system is crucial for clonal propagation and serves as a foundation for future molecular breeding in C. bungei. This study established two in vitro regeneration pathways—indirect somatic embryogenesis and shoot organogenesis utilizing mature zygotic embryos as explants. Primary callus was induced from cotyledon, hypocotyl, and plumule explants. A high frequency (45.73%) of yellow-green compact callus was achieved on De-Klerk and Walton (DKW) medium supplemented with 2.0 mg/L 6-BA, 1.0 mg/L zeatin (ZT), and 0.1 mg/L NAA. Subsequent transfer to 1.5× Murashige and Skoog (MS) medium containing 1.5 mg/L 6-BA, 0.2 mg/L ZT, and 0.1 mg/L NAA yielded the highest embryogenic callus induction rate (16.67%). Embryogenic callus demonstrated bipotent potential, generating both adventitious shoots and somatic embryos under specific hormonal conditions. Histological analyses confirmed the typical developmental stages of somatic embryos, from globular to cotyledonary forms, validating the embryogenic origin of regenerated structures. Furthermore, hormone or osmotic additives such as abscisic acid (ABA), Phytagel, and polyethylene glycol 4000 (PEG4000) significantly enhanced somatic embryo induction, with Phytagel at 5.0 g/L achieving the highest rate (76.31%). For shoot organogenesis, the optimal hormonal combination of the 0.6 mg/L 6-BA, 0.4 mg/L KT, and 0.15 mg/L NAA achieved the highest bud induction rate (88.89%) and produced an average of 4.07 adventitious buds per explant. This study presents an efficient regeneration system for C. bungei, providing a practical platform for large-scale propagation and basis for biotechnological applications in woody plants. Full article

This study established an efficient in vitro regeneration system for Tibouchina granulosato (Desr.) Cogn. petiolated leaves to address the low propagation efficiency and propagatable germplasm shortages. The results revealed that the Murashige and Skoog (MS) medium supplemented with 1.1 mg/L of Zeatin (ZT) and 0.2 mg/L of 1-naphthyl acetic acid (NAA) was the optimal formulation for callus induction, yielding callus induction of 89.59%. For adventitious bud induction, the combination of 2.0 mg/L of 6-benzyladenine (BA) and 0.4 mg/L of NAA proved most effective, achieving an induction rate of 83.33%. Additionally, the adventitious shoots exhibited remarkable elongation when cultured in a medium containing 0.2 mg/L of BA and 0.04 mg/L of NAA. All explants rooted when treated with 0.5 mg/l NAA, inducing a mean number of 6.90 roots per plant and a survival percentage of 91.00%. This study provided technical support for the promotion of superior varieties and genetic improvement of Tibouchina granulosa. Full article

Hypolepis punctata, an aromatic fern with insect-resistant and ornamental potential. Up to date, no studies have reported its micropropagation, particularly using vegetative organs as explants. The optimized stolon sterilization (81.11%) employed 75% ethanol (30 s) and 15% sodium hypochlorite (12 min). The optimal conditions for GGB induction (75.56%) and proliferation (8.46 mm) were achieved using Murashige and Skoog (MS) medium + 2.0 mg/L 6-benzylaminopurine (BA) + 0.2 mg/L 1-naphthaleneacetic acid (NAA). The optimal plant growth regulator (PGR) formula for sporophyte regeneration was 0.5 mg/L BA + 0.1 mg/L NAA + 2 g/L activated charcoal (AC), achieving a 98.89% induction rate and 49.19 buds per explant. The 1/4 MS medium had the greatest promoting effect on biomass accumulation and leaf expansion. Optimal shoot elongation (97.78% success, 4.83 cm) was achieved in 1/4 MS + 0.5 mg/L BA + 0.1 mg/L NAA + 2 g/L AC, and optimized rooting (92.22%) was achieved using 1/4 MS + 0.5 mg/L indole-3-butyric acid (IBA) + 0.1 mg/L NAA + 2 g/L AC, producing 25.27 roots per plantlet. Crucially, ISSR analysis confirmed the genetic stability of all regenerants. This optimized protocol establishes a scalable micropropagation system, enhancing both commercial cultivation and genetic improvement potential in Hypolepis punctata. Full article

Pitaya (Selenicereus undatus) is a long-day climbing cactus that blooms in waves mostly on 1-year old, succulent leafless shoots called cladodes. Nonetheless, pitaya can also bloom on new-year growth if the buds of the cladodes are mature enough and competent for flower induction. Here, we tested, during two consecutive years, whether early pruning could have a positive effect on promoting more flowering waves, better fruiting, and heavier yield of ‘Korean White’ pitaya cultivated in unheated greenhouses of Southeastern Spain. The results show that pruning in January instead of March did not consistently modify the reproductive behavior of ‘Korean White’ pitaya in our conditions. Therefore, no significant effects on the number of blooming waves, flowering intensity, fruit set, quality or yield were observed. The only positive effect, not always significant, was an increase in fruit size that led to better fruit distribution into commercial categories in one out of the two experimental seasons. The lack of effect of early pruning was attributed to the prevalent low temperatures during winter in Spain. The results, however, suggest it is worthwhile exploring whether greenhouse heating with temperatures above pitaya’s base temperature may have the desired effects on increasing blooming waves. The profitability of this practice have to be carefully assessed. Full article

Bombax ceiba is an important medicinal and ornamental tree widely distributed in tropical and subtropical areas. However, its seeds lose viability rapidly after harvest, which has created hurdles in large-scale propagation. Here, we describe the development of a rapid and efficient de novo organogenesis system for Bombax ceiba, incorporating both indirect and direct regeneration pathways. The optimal basal medium used throughout the protocol was ½ MS supplemented with 30 g/L glucose, with all cultures maintained at 26–28 °C. For the indirect pathway, callus was induced from both ends of each hypocotyl on basal medium supplemented with 0.2 mg·L⁻¹ 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.5 mg·L⁻¹ 6-Benzylaminopurine (6-BA) under dark conditions. The induced calluses were subsequently differentiated into adventitious shoots on basal media containing 0.5 mg·L⁻¹ Indole-3-butyric acid (IBA), 0.15 mg·L⁻¹ Kinetin (KIN), and 1 mg·L⁻¹ 6-BA under a 16 h photoperiod, resulting in a callus induction rate of 140% and a differentiation rate of 51%. For the direct regeneration pathway, shoot buds cultured on medium with 0.5 mg·L⁻¹ IBA and 1 mg·L⁻¹ 6-BA achieved a 100% sprouting rate with a regeneration coefficient of approximately 3.2. The regenerated adventitious shoots rooted successfully on medium supplemented with 0.5 mg·L⁻¹ Naphthylacetic acid (NAA) and were acclimatized under greenhouse conditions to produce viable plantlets. This regeneration system efficiently utilizes sterile seedling explants, is not limited by seasonal or environmental factors, and significantly improves the propagation efficiency of Bombax ceiba. These optimized micropropagation methods also provide a robust platform for future genetic transformation studies using hypocotyls and shoot buds as explants. Full article

Turmeric (Curcuma longa L. cv. Trang 1), a high-value cultivar known for its elevated curcuminoid and volatile oil content, holds significant potential in pharmaceutical and food applications. However, its commercial propagation is constrained by low rhizome productivity and the limitations of conventional vegetative propagation. This study aimed to improve the propagation efficiency of turmeric cv. Trang 1 by developing optimized protocols for explant sterilization, shoot proliferation, root induction, and acclimatization. Sprouted rhizome buds were sterilized and cultured on a Murashige and Skoog (MS) medium supplemented with various plant growth regulators, including cytokinins (benzyladenine [BA], thidiazuron [TDZ], and meta-topolin [mT]) and auxins (indole-3-butyric acid [IBA] and 1-naphthaleneacetic acid [NAA]). The shoot induction (4.60 ± 1.47 shoots per explant) and shoot height (2.34 ± 0.61 cm) were observed on the MS medium with 3.0 mg/L BA, while the TDZ, at 0.5 mg/L, also induced a high number of shoots (5.22 ± 0.64). When using single shoots derived from bud explants, mT at 1.5 mg/L significantly enhanced the shoot formation. For the root induction, 2.0 mg/L IBA yielded the highest number of roots (7.33 ± 1.49), while NAA was less effective. The plantlets acclimatized in a 1:1 soil and peat moss mixture showed the highest survival rate (86.67%). This improved protocol enables the efficient production of turmeric plantlets, supporting commercial deployment. Full article

Viburnum opulus L. ‘Roseum’ is a highly valuable ornamental plant for landscaping, but it has a long propagation cycle and low propagation coefficient. In this study, stem segments with axillary buds from Viburnum opulus L. ‘Roseum’ were used as explants. We systematically analyzed the use of sodium hypochlorite for the sterilization of explants, as well as the effects of different plant growth regulator combinations and concentrations on shoot bud induction, shoot proliferation, the rooting of tissue-cultured shoots, and the transplanting of the tissue-cultured shoots. A complete rapid propagation technology system for Viburnum opulus L. ‘Roseum’ was established. The results showed that a disinfection method using 75% ethanol for 30 s and soaking in 5% sodium hypochlorite for 5 min was the most suitable for disinfecting the stem segments of Viburnum opulus L. ‘Roseum’, which showed low contamination and a 73.33% survival rate. The ideal medium for primary bud induction was WPM (Woody Plant Basal Medium) + 2.0 mg·L⁻¹ 6-benzylaminopurine (6-BA) + 0.15 mg·L⁻¹ indole-3-butyric acid solution (IBA) + 25 g·L⁻¹ sucrose. The optimal medium for shoot proliferation was WPM + 1.0 mg·L⁻¹ 6-BA + 0.15 mg·L⁻¹ IBA + 25 g·L⁻¹ sucrose, achieving an induction rate of 7.17. For the rooting of tissue-cultured shoots, the most suitable formulation was 1/2 WPM + 0.3 mg·L⁻¹ naphthaleneacetic acid (NAA) + 0.3 mg·L⁻¹ activated charcoal (AC) + 25 g·L⁻¹ sucrose, which induced robust and developed root systems. This study provides a technical basis for the establishment of a fast propagation system for the industrial production of Viburnum opulus L. ‘Roseum’. Full article