Search Results (379)

Jujube (Ziziphus jujuba Mill.) is an important economic fruit tree in China, and its in vitro culture technology is the key to achieving large-scale seedling cultivation. PGRs (Plant growth regulators) play a central regulatory role in all stages of jujube micropropagation, including explant initiation, proliferation, and rooting. This article provides a comprehensive overview of recent advances in in vitro culture of jujube, with a focus on the recommended exogenous phytohormone ratios, their effects, and underlying regulatory mechanisms across distinct varieties during the key stages such as in vitro culture, shoot proliferation, and root formation. The primary culture of most jujube varieties usually employs the MS medium, and it is recommended that auxin and cytokinin be used in combination. During the initial cultivation stage, the use of NAA (1-naphthaleneacetic acid) or IBA (indole butyric acid) is recommended at concentrations ranging from 0.1 to 1.0 mg/L. At the same time, 6-BA (6-benzylaminopurine) is suggested, with a concentration range of 0.5 to 2.5 mg/L. In the subculture multiplication of most jujube varieties, MS medium is used, and auxin (such as NAA, IBA), and TDZ (thidiazuron) and cytokinin (e.g., 6-BA) are used in combination. The recommended concentration range for auxin remains between 0.1 and 1.0 mg/L, and for cytokinin 6-BA between 0.5 and 2.5 mg/L, while the recommended concentration of TDZ is suggested to be below 0.01 mg/L. Rooting induction for most jujube varieties has predominantly been achieved using 1/2 MS medium, with growth regulator concentrations typically ranging from 0.5 to 3.0 mg/L. Full article

Nitrogen is an essential macronutrient for crop growth. Although sorghum can tolerate poor soils, its low-nitrogen (LN) tolerance mechanisms remain underexplored. We conducted a genome-wide association study (GWAS) and RNA sequencing (RNA-seq) to dissect LN tolerance mechanisms in a diverse panel of 232 sorghum accessions. Phenotypic analyses revealed extensive variation in nitrogen-use efficiency traits, with shoot dry weight and shoot nitrogen accumulation in (SNAcc) showing the highest diversity. GWAS identified 10 quantitative trait loci harboring pleiotropic single-nucleotide polymorphisms (SNPs), including q1 (Chr3: 8.59–8.68 Mb), which is associated with biomass and nitrogen accumulation. Transcriptome profiling under LN stress revealed 6208 differentially expressed genes, with nitrate transporters showing genotype-specific regulation. Integration prioritized SORBI_3004G286700, where Hap2 accessions (14.66%) showed superior agronomic performance under LN conditions. We also identified pivotal transcription factors (TFs) that govern LN tolerance in sorghum, notably bHLH35 (SORBI_3007G051800) and three WRKY TFs, demonstrating constitutive upregulation in tolerant genotypes, whereas three previously uncharacterized TFs (MYB, bZIP, and B3) exhibited > 5-fold genotype-specific induction under LN. The integration of GWAS and transcriptome analyses offers an effective strategy for exploring candidate genes and elucidating nitrogen adaptation mechanisms in sorghum, while providing actionable molecular targets for precise breeding of nitrogen-efficient cultivars. 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

The aim of the present study was to evaluate the morphogenetic efficiency of the new flax (Linum usitatissimum L.) cultivar Silesia. The plant material consisted of five ecotypes of Silesia seeds selected by determining the fatty acid composition in individual plants. Thus, five ecotypes with different fatty acid compositions were applied for germination, and the resulting seedlings were used for callus induction. The observed in vitro morphogenic response of explants to the used callus induction medium was 100%, followed by varying development of shoots, with the highest value being 17 shoots per callus, with an average length of 7.15 cm (for ecotype 1). The biochemical analyses showed photosynthetic pigments were significantly affected by the tested ecotypes. The main conclusion is that the selection of plant material as a source of tissue cultures is crucial for efficient regeneration and organogenesis. One factor potentially influencing these processes is fatty acid composition and the ratio of linoleic to α-linolenic acid. A ratio ranging from 1.36 to 1.68 in the source material (seeds) used for initiation of tissue cultures resulted in the highest efficiency of shoot regeneration and number of obtained shoots per callus. A strong negative correlation (−0.78) was observed between shoot regeneration efficiency and the ratio of linoleic to α-linolenic acid in seeds from which the explants were obtained. Moreover, an efficient protocol of micropropagation from callus tissue was established for the new flax cultivar Silesia. An interesting insight into the metabolism of the obtained regenerants allowed us to determine the relationship between the content of chlorophyll and rhizogenesis efficiency. For these two parameters, the calculated correlation coefficient was 0.66. A strong relationship (high correlation coefficient: 0.79) was also established between flavonoid content and length of obtained regenerants, pointing to the developmental role of flavonoids. Full article

Conventional propagation of the highly sought-after ornamental Philodendron erubescens ‘Pink Princess’ is constrained by slow multiplication rates, the risk of unstable variegation, and the limited availability of elite mother stock, making advanced in vitro techniques essential for large-scale production. This research aimed to establish an efficient micropropagation protocol by optimizing the shoot multiplication phase in a twin-flask Temporary Immersion Bioreactor (TIB) system (RITA-type) and subsequently assessing the genetic fidelity of the regenerated plants. Shoot induction was evaluated in a TIB system with an immersion frequency of 4 min every 8 h. Among the tested cytokinins, liquid Murashige and Skoog (MS) medium containing 1.0 mg/L 6-benzylaminopurine (BAP) provided the optimal conditions for shoot proliferation, accounting for approximately 21 shoots/explant. While the TIB system was highly effective for shoot multiplication, it proved suboptimal for root induction. Therefore, rooting was optimized on a semi-solid medium, where MS medium supplemented with 0.5 mg/L indole-3-acetic acid (IAA) was identified as the most effective treatment, yielding an average of 3.0 well-developed roots per explant (1.1 cm in length) within 30 days. For acclimatization, a substrate mix of peat moss, perlite, and vermiculite (2:1:1, v/v/v) ensured a 100% survival rate. Critically, genetic fidelity analysis using RAPD markers revealed monomorphic banding patterns between the micropropagated plantlets and the mother plant (100% similarity), confirming their genetic uniformity and true-to-type nature. The established protocol provides a robust and reliable method for the in vitro propagation of P. erubescens ‘Pink Princess’. This work offers a foundation for developing large-scale commercial production strategies and effectively overcomes many limitations of classical propagation techniques. Full article

Hypericum aucheri is a Hypericum species distributed in Türkiye as well as Greece and Bulgaria with notable pharmacological potential. Its medicinal importance underlines the need for effective propagation strategies. This study developed an in vitro micropropagation protocol using nodal explants cultured on Murashige and Skoog (MS) medium supplemented with different concentrations of cytokinins—6-benzylaminopurine (BAP) (0, 1, 2 mg L⁻¹) or kinetin (KIN) (0, 1, 2 mg L⁻¹)—combined with 2,4-dichlorophenoxyacetic acid (2,4-D) (0, 0.5, 1 mg L⁻¹) for shoot induction. The highest shoot induction and multiplication (100% and multiplication coefficient of 10.0) were achieved with KIN (2 mg L⁻¹). Rooting was most successful on MS medium supplemented with α-naphthaleneacetic acid (NAA) (1 mg L⁻¹) and activated charcoal (AC) (1 mg L⁻¹), resulting in 100% rooting. Acclimatized plantlets showed an 80% survival rate under ex vitro conditions. This study presents the first efficient micropropagation system for H. aucheri, contributing to its ex situ conservation and providing a foundation for future pharmacological and biotechnological research. Full article

This study aimed to investigate culture conditions for the efficient micropropagation of apple cultivars ‘Golden Delicious’ and ‘Royal Gala’ in liquid medium by temporary immersion. RITA^® bioreactors were used for the multiplication stage whereas RITA^® or Plantform™ were used for the rooting stage. Murashige and Skoog media (MS) with N⁶-benzyladenine (BA) was used for shoot multiplication and indole-3-butyric acid (IBA) for root induction. During the multiplication phase, we evaluated the mineral medium, BA concentration, immersion frequency, silver nitrate and activated charcoal supplementation and the use of physical supports to hold explants in an upright position. The results demonstrated that longer incubation periods (10 weeks) were better than shorter periods (6 weeks) for decreasing hyperhydricity and increasing the multiplication coefficient (MC). For ‘Golden Delicious’, the highest MC were obtained either with explants placed directly on the bioreactor basket and immersed six times per day for 60 s in MS with 2.2 µM BA or explants placed between rockwool cubes cultivated with 4.4 µM BA (both yielding MC of 8.9 and 5–10% hyperhydricity). These results were superior to ‘Royal Gala’, which showed a MC of 7.3 and 23% of hyperhydricity when cultivated in MS with half nitrates, 1.55 µM BA and rockwool cubes. Both varieties rooted efficiently (96–100%), and resulting plantlets were successfully acclimated. This is the first report in the micropropagation of these two commercial fruiting cultivars in temporary immersion, demonstrating the potential of this technology to enhance large-scale plant production for the apple nursery industry. Full article

Iris laevigata is an ornamental plant and so its wild genetic resources need to be protected. However, traditional inefficient propagation limits its landscape applications. In this study, we assessed the effects of phytohormones on growth of I. laevigata at various culture stages using roots and hypocotyls as explants and established an efficient micropropagation system. The highest callus induction of hypocotyl (75.0%) was obtained using Murashige and Skoog medium containing 6-benzylaminopurine (6-BA), 0.5 mg L⁻¹ + 2,4-dichlorophenoxyacetic acid (2,4-D), 1.0 mg L⁻¹ + 1-naphthylacetic acid (NAA), and 0.4 mg L⁻¹. Similarly, the highest callus induction (73.3%) of roots was achieved with 6-BA 0.5 mg L⁻¹ + 2,4-D 0.5 mg L⁻¹ + NAA 0.4 mg L⁻¹. The calli induced from hypocotyl and root tissues achieved 39.7% and 49.5% adventitious shoot induction on a medium containing indole-3-butyric acid (IBA) 0.5 mg L⁻¹ + 6-BA 1.5 mg L⁻¹ + NAA 1.0 mg L⁻¹ and 6-BA 2.0 mg L⁻¹ + NAA 0.4 mg L⁻¹ + kinetin (KT) 1.0 mg L⁻¹, respectively. The rooting of adventitious shoots reached 93.3% in the medium supplemented with NAA 0.2 mg L⁻¹. The survival of regenerated plants reached 90.0% after being transplanted into soil. This study provides an efficient and reliable propagation method for I. laevigata for landscape applications and the preservation of wild genetic material. 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

Rice blast is one of the main diseases of rice, causing severe economic losses to agricultural production; thus, the search for blast resistance is a top priority for rice breeding. When challenged by the blast causal fungus Magnaporthe oryzae the expression level of OsMAPKKK69 gene in rice cultivar Nipponbar was found to increase significantly. Such an induction was also found in a different genetic material, cultivar Shufanggaonuo, indicating that OsMAPKKK69 plays an important role in blast disease response. However, the function of OsMAPKKK69 remains unclear. In this study, wild type ZH11 was selected as the background material to investigate the expression and functions of OsMAPKKK69 in rice disease resistance by constructing knockout mutants. The results showed that OsMAPKKK69 is mainly expressed in four-week-old shoots and localized in cell membrane, cytoplasm, and nucleus. The two allelic knockout mutants, osmapkkk69-1 and osmapkkk69-2, were more resistant to M. oryzae and bacterial blight Xanthomonas oryzae pv. Oryzae (Xoo). Further agronomic trait analysis revealed that the osmapkkk69-1 and osmapkkk69-2 mutants had reduced plant height, smaller grain size, a significant increase in tillering number, but also a significant increase in yield per plant. Our results show that OsMAPKKK69 is involved in the immune response of rice by negatively regulating the resistance to rice blast and blight diseases, and in regulating important agronomic traits. This study lays a foundation for revealing the molecular mechanism of OsMAPKKK69 in the immune response to rice diseases and provides novel genetic resources for rice breeding. Full article

Rhaponticum carthamoides (Willd.) Iljin. (Leuzea carthamoides, Maral root), a medicinally valuable species listed in the Red Book of Kazakhstan, is known for its rich phytochemical profile. However, limited data exist on its microclonal propagation. This study aimed to optimize in vitro and medium-term storage conditions using biotechnological methods. Mature seeds collected from natural populations in the Kazakhstani Altai were germinated, and tissues from the seedlings were used as explants. Sterile shoots were cultured on Murashige and Skoog (MS) medium supplemented with 3.0 mg L⁻¹ −6-benzylaminopurine and 3.0 mg L⁻¹ kinetin. For shoot induction, MS medium supplemented with 0.5 mg L⁻¹ meta-Topolin and using stem apices as explants yielded optimal results. Medium-term storage with chlorocholine chloride at 0.1–0.4 g/L effectively preserved regenerative capacity for further rooting. After 12 months of storage, plantlets were transferred to half-strength MS medium with 3.0 g/L activated carbon and at 2.0 or 5.0 mg L⁻¹ indole-3-butyric acid for rooting. Regenerated plants were successfully acclimatized ex vitro. The 20-hydroxyecdysone content in field-grown plants post-storage reached 9.24 mg/mL, 2.4-fold higher than in wild plants. Inter simple sequence repeat analysis confirmed genetic stability. Our optimized protocol ensures high-yield metabolite production and genetic fidelity, enabling in vitro conservation, nursery-scale cultivation, and the restoration of R. carthamoides natural populations. Full article

Purpose: To investigate the impact of mental fatigue on the shooting accuracy and movement timing in the instep kick of Asian high-level soccer players. Methods: Eight male collegiate soccer players (age 22.00 ± 0.93 years) were tested before and after mental fatigue induction. Mental fatigue was induced via a 30 min Stroop task. The effectiveness of fatigue induction was assessed using heart rate variability (HRV), a visual analog scale (VAS), rating of perceived exertion (RPE), and the Athlete Burnout Questionnaire (ABQ). Shooting performance was evaluated before and after mental fatigue using the Loughborough Soccer Shooting Test (LSST) and by evaluating timing by means of high-speed imaging. Results: Following mental fatigue induction, HRV decreased. Subjects’ motivation (VAS) to exercise significantly decreased (p < 0.001), while VAS mental fatigue level (p < 0.001) and mental effort level (p < 0.002) significantly increased. Significant differences were observed after completing the Stroop task for ABQ Emotional/Physical Exhaustion (p < 0.007), Reduced Sense of Accomplishment (p < 0.007), Sport Devaluation (p < 0.006), and overall burnout level (p < 0.002). LSST showed that the subjects’ left foot test scores (−4.13, p < 0.013), right foot test scores (−3, p < 0.001), and total scores (−3.16, p < 0.001) significantly decreased. Although movement times increased slightly after fatigue, they did not reach statistical significance. Conclusions: Mental fatigue significantly impairs the shooting accuracy of collegiate soccer players, as evidenced by decreased LSST scores. However, it has no significant effect on event duration during shooting execution. Mental fatigue affected decision-making but not shooting movement timing. More cognitively challenging tasks are more affected by mental fatigue. 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