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1.
Sci Rep ; 14(1): 9499, 2024 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664438

RESUMO

Sorghum is a vital food and feed crop in the world's dry regions. Developing sorghum cultivars with high biomass production and carbon sequestration can contribute to soil health and crop productivity. The objective of this study was to assess agronomic performance, biomass production and carbon accumulation in selected sorghum genotypes for production and breeding. Fifty sorghum genotypes were evaluated at three locations (Silverton, Ukulinga, and Bethlehem) in South Africa during 2022 and 2023 growing seasons. Significant genotype × location (p < 0.05) interactions were detected for days to 50% heading (DTH), days to 50% maturity (DTM), plant height (PH), total plant biomass (PB), shoot biomass (SB), root biomass (RB), root-to-shoot biomass ratio (RS), and grain yield (GY). The highest GY was recorded for genotypes AS115 (25.08 g plant-1), AS251 (21.83 g plant-1), and AS134 (21.42 g plant-1). Genotypes AS122 and AS27 ranked first and second, respectively, for all the carbon stock parameters except for root carbon stock (RCs), whereas genotype AS108 had the highest RCs of 8.87 g plant-1. The principal component analysis identified GY, DTH, PH, PB, SB, RB, RCs, RCs/SCs, total plant carbon stock (PCs), shoot carbon stock (SCs), and grain carbon stock (GCs) as the most discriminated traits among the test genotypes. The cluster analysis using agronomic and carbon-related parameters delineated the test genotypes into three genetic groups, indicating marked genetic diversity for cultivar development and enhanced C storage and sustainable sorghum production. The selected sorghum genotypes are recommended for further breeding and variety release adapted to various agroecologies in South Africa.


Assuntos
Biomassa , Carbono , Genótipo , Raízes de Plantas , Brotos de Planta , Sorghum , Sorghum/genética , Sorghum/crescimento & desenvolvimento , Sorghum/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Carbono/metabolismo , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/metabolismo , África do Sul , Melhoramento Vegetal , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo
2.
Cryo Letters ; 45(2): 122-133, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38557991

RESUMO

BACKGROUND: Acorus calamus Linn. is a medicinally valuable monocot plant belonging to the family Acoraceae. Over-exploitation and unscientific approach towards harvesting to fulfill an ever-increasing demand have placed it in the endangered list of species. OBJECTIVE: To develop vitrification-based cryopreservation protocols for A. calamus shoot tips, using conventional vitrification and V cryo-plate. MATERIALS AND METHODS: Shoot tips (2 mm in size) were cryopreserved with the above techniques by optimizing various parameters such as preculture duration, sucrose concentration in the preculture medium, and PVS2 dehydration time. Regenerated plantlets obtained post-cryopreservation were evaluated by random amplified polymorphic DNA (RAPD) to test their genetic fidelity. RESULTS: The highest regrowth of 88.3% after PVS2 exposure of 60 min was achieved with V cryo-plate as compared to 75% after 90 min of PVS2 exposure using conventional vitrification. After cryopreservation, shoot tips developed into complete plantlets in 28 days on regrowth medium (0.5 mg/L BAP, 0.3 mg/L GA3, and 0.3 mg/L ascorbic acid). RAPD analysis revealed 100% monomorphism in all cryo-storage derived regenerants and in vitro donor (120-days-old) plants. CONCLUSION: Shoot tips of A. calamus that were cryopreserved had 88.3% regrowth using V cryo-plate technique and the regerants retained genetic fidelity. https://doi.org/10.54680/fr24210110412.


Assuntos
Acorus , Plantas Medicinais , Criopreservação/métodos , Plantas Medicinais/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Brotos de Planta/genética , Vitrificação , Crioprotetores
3.
Physiol Plant ; 176(2): e14301, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38629128

RESUMO

Salt stress is one of the major factors that limits rice production. Therefore, identification of salt-tolerant alleles from wild rice is important for rice breeding. In this study, we constructed a set of chromosome segment substitution lines (CSSLs) using wild rice as the donor parent and cultivated rice Nipponbare (Nip) as the recurrent parent. Salt tolerance germinability (STG) was evaluated, and its association with genotypes was determined using this CSSL population. We identified 17 QTLs related to STG. By integrating the transcriptome and genome data, four candidate genes were identified, including the previously reported AGO2 and WRKY53. Compared with Nip, wild rice AGO2 has a structure variation in its promoter region and the expression levels were upregulated under salt treatments; wild rice WRKY53 also has natural variation in its promoter region, and the expression levels were downregulated under salt treatments. Wild rice AGO2 and WRKY53 alleles have combined effects for improving salt tolerance at the germination stage. One CSSL line, CSSL118 that harbors these two alleles was selected. Compared with the background parent Nip, CSSL118 showed comprehensive salt tolerance and higher yield, with improved transcript levels of reactive oxygen species scavenging genes. Our results provided promising genes and germplasm resources for future rice salt tolerance breeding.


Assuntos
Genes de Plantas , Oryza , Melhoramento Vegetal , Tolerância ao Sal , Oryza/anatomia & histologia , Oryza/genética , Oryza/crescimento & desenvolvimento , Tolerância ao Sal/genética , Cromossomos de Plantas/genética , Alelos , Melhoramento Vegetal/métodos , Locos de Características Quantitativas/genética , Genótipo , Transcriptoma , Genoma de Planta/genética , Regiões Promotoras Genéticas , Regulação da Expressão Gênica de Plantas , Germinação , Brotos de Planta , Raízes de Plantas , Técnicas de Genotipagem , Polimorfismo Genético , Fenótipo
4.
Sci Rep ; 14(1): 5586, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454056

RESUMO

The present study was conducted in the Laboratory of Tissue Culture, Horticulture Department, Faculty of Agriculture, Damietta University, Egypt. The objective of this study was to establish a micropropagation protocol suitable for three imported peach rootstocks: Okinawa (P. persica), Nemared (P. persica × P. davidiana) × P. persica), and Garnem (P. dulcis × P. persica) in vitro. The results showed that soaking the explants in sodium hypochlorite (NaOCl) at 20% for 15 min produced the highest responsiveness (82.81%), survival (96.61%), with the lowest mortality (3.14%) and contamination (0.24%). Explants of the Garnem genotype had the best response (89.12%), survival (90.62%), lowest mortality (0.00%), and highest contamination (9.37%) when compared to the other genotypes. In comparison with axillary buds, the shoot tip displayed the highest responsiveness, survival, and death (100, 87.40, and 12.59%, respectively), as well as the least significant contamination (0.00%). Additionally, the percentages of responsive, survived, dead, and contaminated explants at the various collection dates varied significantly. The 6-benzylaminopurine (BAP) concentrations used (3 to 5.0 mg/L) demonstrated similar behavior in terms of in vitro proliferation, with rates of 3.77 to 6.11, 4.33 to 8.88, and 3.33 to 7.44 shoot numbers per explant for the Okinawa, Nemared, and Garnem peach rootstocks, respectively, indicating that the number of shoot proliferations is genotype-dependent. Additionally, using 5.0 mg/L BAP in combination with 0.2 mg/L IBA significantly increased average shoot proliferation (96.29%), number of shoots per explant (7.48), and average leaf number/explant (16.33) compared to the other treatments. Based on these results, adventitious bud development was enhanced during in vitro multiplication of the Okinawa, Nemared, and Garnem peach rootstocks by the synergistic interaction of indole-butyric acid (IBA) and 6-benzylaminopurine (BAP).


Assuntos
Prunus persica , Purinas , Humanos , Brotos de Planta , Compostos de Benzil , Proliferação de Células
5.
Planta ; 259(5): 101, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38536474

RESUMO

MAIN CONCLUSION: Axillary meristems (AMs) located in the leaf axils determine the number of shoots or tillers eventually formed, thus contributing significantly to the plant architecture and crop yields. The study of AM initiation is unavoidable and beneficial for crop productivity. Shoot branching is an undoubted determinant of plant architecture and thus greatly impacts crop yield due to the panicle-bearing traits of tillers. The emergence of the AM is essential for the incipient bud formation, and then the bud is dormant or outgrowth immediately to form a branch or tiller. While numerous reviews have focused on plant branching and tillering development networks, fewer specifically address AM initiation and its regulatory mechanisms. This review synthesizes the significant advancements in the genetic and hormonal factors governing AM initiation, with a primary focus on studies conducted in Arabidopsis (Arabidopsis thaliana L.) and rice (Oryza sativa L.). In particular, by elaborating on critical genes like LATERAL SUPPRESSOR (LAS), which specifically regulates AM initiation and the networks in which they are involved, we attempt to unify the cascades through which they are positioned. We concentrate on clarifying the precise mutual regulation between shoot apical meristem (SAM) and AM-related factors. Additionally, we examine challenges in elucidating AM formation mechanisms alongside opportunities provided by emerging omics approaches to identify AM-specific genes. By expanding our comprehension of the genetic and hormonal regulation of AM development, we can develop strategies to optimize crop production and address global food challenges effectively.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Meristema , Proteínas de Plantas/metabolismo , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Brotos de Planta , Proteínas de Arabidopsis/metabolismo
6.
Biomolecules ; 14(3)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38540799

RESUMO

Numerous biotechnological applications require a fast and efficient clonal propagation of whole plants under controlled laboratory conditions. For most plant species, the de novo regeneration of shoots from the cuttings of various plant organs can be obtained on nutrient media supplemented with plant hormones, auxin and cytokinin. While auxin is needed during the early stages of the process that include the establishment of pluripotent primordia and the subsequent acquisition of organogenic competence, cytokinin-supplemented media are required to induce these primordia to differentiate into developing shoots. The perception of cytokinin through the receptor ARABIDOPSIS HISTIDINE KINASE4 (AHK4) is crucial for the activation of the two main regulators of the establishment and maintenance of shoot apical meristems (SAMs): SHOOTMERISTEMLESS (STM) and the WUSCHEL-CLAVATA3 (WUS-CLV3) regulatory circuit. In this review, we summarize the current knowledge of the roles of the cytokinin signaling cascade in the perception and transduction of signals that are crucial for the de novo establishment of SAMs and lead to the desired biotechnological output-adventitious shoot multiplication. We highlight the functional differences between individual members of the multigene families involved in cytokinin signal transduction, and demonstrate how complex genetic regulation can be achieved through functional specialization of individual gene family members.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Meristema , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brotos de Planta/genética , Arabidopsis/fisiologia , Citocininas , Transdução de Sinais , Ácidos Indolacéticos , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/metabolismo
8.
Food Chem ; 448: 139075, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38531300

RESUMO

Sulfur-containing compounds are responsible for the aroma of Toona sinensis shoot (TS). In this study, vacuum-freeze-drying (VFD), microwave-drying (MD), and hot-air-drying at 100 and 40 °C (HAD100 and HAD40, respectively), were applied to dehydrate perishable TS for preservation. VFD-TS retained most aroma of fresh/raw TS after rehydration. The content of sulfur-containing compounds reached to 118.00 µg/g with leading by methyl thiirane, (E,E)/(E,Z)/(Z,Z)-bis-(1-propenyl) disulfides, and (Z)/(E)-2-mercapto-3,4-dimethyl-2,3-dihydrothiophenes accounting for 86.33 %. They were undetected in the rehydrated MD-TS and HAD100-TS, as the indigenous enzymes in TS were deactivated under their dehydration conditions. Interestingly, the sulfur-containing compounds was restored by 77.47 % after the TS was treated by gamma-glutamyl transferase (GGT). Thus, the release of sulfur-containing compounds from TS could depend on GGT reaction. It was different from alliaceous vegetables relying on alliinase reaction. The results revealed the aroma formation in TS and provided an approach to enhance the aroma of TS dried by different methods.


Assuntos
Dessecação , gama-Glutamiltransferase , Dessecação/métodos , gama-Glutamiltransferase/metabolismo , Humanos , Odorantes/análise , Brotos de Planta/química , Paladar , Compostos de Enxofre/química , Compostos de Enxofre/análise , Liofilização
9.
New Phytol ; 242(3): 1084-1097, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38503686

RESUMO

Arabidopsis thaliana (Arabidopsis) shoot architecture is largely determined by the pattern of axillary buds that grow into lateral branches, the regulation of which requires integrating both local and systemic signals. Nodal explants - stem explants each bearing one leaf and its associated axillary bud - are a simplified system to understand the regulation of bud activation. To explore signal integration in bud activation, we characterised the growth dynamics of buds in nodal explants in key mutants and under different treatments. We observed that isolated axillary buds activate in two genetically and physiologically separable phases: a slow-growing lag phase, followed by a switch to rapid outgrowth. Modifying BRANCHED1 expression or the properties of the auxin transport network, including via strigolactone application, changed the length of the lag phase. While most interventions affected only the length of the lag phase, strigolactone treatment and a second bud also affected the rapid growth phase. Our results are consistent with the hypothesis that the slow-growing lag phase corresponds to the time during which buds establish canalised auxin transport out of the bud, after which they enter a rapid growth phase. Our work also hints at a role for auxin transport in influencing the maximum growth rate of branches.


Assuntos
Arabidopsis , Compostos Heterocíclicos com 3 Anéis , Ácidos Indolacéticos , Ácidos Indolacéticos/farmacologia , Ácidos Indolacéticos/metabolismo , Arabidopsis/metabolismo , Brotos de Planta/metabolismo , Lactonas/farmacologia , Lactonas/metabolismo , Regulação da Expressão Gênica de Plantas
10.
Int J Mol Sci ; 25(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338798

RESUMO

The shoot apical meristem (SAM) gives rise to the aerial structure of plants by producing lateral organs and other meristems. The SAM is responsible for plant developmental patterns, thus determining plant morphology and, consequently, many agronomic traits such as the number and size of fruits and flowers and kernel yield. Our current understanding of SAM morphology and regulation is based on studies conducted mainly on some angiosperms, including economically important crops such as maize (Zea mays) and rice (Oryza sativa), and the model species Arabidopsis (Arabidopsis thaliana). However, studies in other plant species from the gymnosperms are scant, making difficult comparative analyses that help us understand SAM regulation in diverse plant species. This limitation prevents deciphering the mechanisms by which evolution gave rise to the multiple plant structures within the plant kingdom and determines the conserved mechanisms involved in SAM maintenance and operation. This review aims to integrate and analyze the current knowledge of SAM evolution by combining the morphological and molecular information recently reported from the plant kingdom.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Oryza , Meristema/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Zea mays/metabolismo , Plantas/metabolismo , Oryza/metabolismo , Regulação da Expressão Gênica de Plantas , Brotos de Planta/genética , Brotos de Planta/metabolismo
11.
Biosci Biotechnol Biochem ; 88(4): 412-419, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38412471

RESUMO

The regeneration of shoots from endosperm tissue is a highly effective method to obtain triploid plants. In this study, we elucidated the establishment of an in vitro regeneration system from endosperm culture for the production of Passiflora edulis "Mantianxing." The highest callus induction rate (83.33%) was obtained on the media supplemented with 1.0 mg/L TDZ. Meanwhile, the MS medium containing 1.0 mg/L 6-BA and 0.4 mg/L IBA gave the optimum 75% shoot bud induction. Chromosome analysis revealed that the chromosomal count of P. edulis "Mantianxing" regenerated from endosperm tissues was 27 (2n = 3x = 27), which indicated that shoots regenerated from endosperm tissues were triploids. Triploid P. edulis had more drought resistance than diploid plants. Our study provided a method for breeding of passion fruit by means of a stable and reproducible regeneration system from endosperm culture, leading to the generation of triploid plants.


Assuntos
Passiflora , Triploidia , Brotos de Planta , Endosperma , Melhoramento Vegetal , Regeneração/genética
12.
BMC Res Notes ; 17(1): 45, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38311772

RESUMO

OBJECTIVE: The high industrial demand for Stevia cultivation (Stevia rebaudiana) has increased due to its high stevioside content derived from the leaves. However, the low germination rate makes the cultivation of the plant become the main obstacle. Therefore, an efficient cultivation technique is required. This present work aims to analyze the effect of five combinations of Kinetin (Kin) and benzyladenine (BA) on stevia micropropagation using nodal segment explants. RESULTS: The micropropagation of stevia was performed using Murashige and Skoog (MS) medium supplemented with BA and Kin. We analyzed different organogenesis and callogenesis responses. In addition, the number of shoots and root formed during in vitro culture were also observed. Our results demonstrated that all treatments with Kin, both alone and in combination with BA, resulted in the development of callus on all nodal segment explants. Explants treated in MS with 1 mg L-1 BA exhibited the best average of shoot number (36.27). In contrast, the treatment without PGR resulted in the best root formation (2.6). The overall results suggested that different combination of BA and Kin resulted in distinct organogenesis responses, where 1 mg L-1 of BA was potentially used for boosting the number of shoots in micropropagation of stevia accession Mini.


Assuntos
Stevia , Stevia/genética , Indonésia , Brotos de Planta , Genótipo , Folhas de Planta
13.
Nature ; 625(7996): 750-759, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38200311

RESUMO

Iron is critical during host-microorganism interactions1-4. Restriction of available iron by the host during infection is an important defence strategy, described as nutritional immunity5. However, this poses a conundrum for externally facing, absorptive tissues such as the gut epithelium or the plant root epidermis that generate environments that favour iron bioavailability. For example, plant roots acquire iron mostly from the soil and, when iron deficient, increase iron availability through mechanisms that include rhizosphere acidification and secretion of iron chelators6-9. Yet, the elevated iron bioavailability would also be beneficial for the growth of bacteria that threaten plant health. Here we report that microorganism-associated molecular patterns such as flagellin lead to suppression of root iron acquisition through a localized degradation of the systemic iron-deficiency signalling peptide Iron Man 1 (IMA1) in Arabidopsis thaliana. This response is also elicited when bacteria enter root tissues, but not when they dwell on the outer root surface. IMA1 itself has a role in modulating immunity in root and shoot, affecting the levels of root colonization and the resistance to a bacterial foliar pathogen. Our findings reveal an adaptive molecular mechanism of nutritional immunity that affects iron bioavailability and uptake, as well as immune responses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Bactérias , Peptídeos e Proteínas de Sinalização Intracelular , Ferro , Moléculas com Motivos Associados a Patógenos , Raízes de Plantas , Arabidopsis/imunologia , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Proteínas de Arabidopsis/metabolismo , Bactérias/imunologia , Bactérias/metabolismo , Flagelina/imunologia , Regulação da Expressão Gênica de Plantas , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ferro/metabolismo , Imunidade Vegetal , Raízes de Plantas/imunologia , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Brotos de Planta/imunologia , Brotos de Planta/metabolismo , Brotos de Planta/microbiologia , Rizosfera , Moléculas com Motivos Associados a Patógenos/imunologia , Moléculas com Motivos Associados a Patógenos/metabolismo
14.
Curr Opin Plant Biol ; 78: 102510, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38266375

RESUMO

Plant meristems contain pools of dividing stem cells that produce new organs for plant growth and development. Environmental factors, including biotic and abiotic stresses and nutrient availability, affect meristem activity and thus the architecture of roots and shoots; understanding how meristems react to changing environmental conditions will shed light on how plants optimize nutrient acquisition and acclimate to different environmental conditions. This review highlights recent exciting advances in this field, mainly in Arabidopsis. We discuss the signaling pathways, genetic regulators, and molecular mechanisms involved in the response of plant meristems to environmental and nutrient cues, and compare the similarities and differences of stress responses between the shoot and root apical meristems.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Meristema/metabolismo , Transdução de Sinais/fisiologia , Arabidopsis/genética , Plantas/metabolismo , Proteínas de Arabidopsis/metabolismo , Células-Tronco/metabolismo , Brotos de Planta/genética , Regulação da Expressão Gênica de Plantas
15.
Nat Plants ; 10(2): 315-326, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38195907

RESUMO

Intracellular inorganic orthophosphate (Pi) distribution and homeostasis profoundly affect plant growth and development. However, its distribution patterns remain elusive owing to the lack of efficient cellular Pi imaging methods. Here we develop a rapid colorimetric Pi imaging method, inorganic orthophosphate staining assay (IOSA), that can semi-quantitatively image intracellular Pi with high resolution. We used IOSA to reveal the alteration of cellular Pi distribution caused by Pi starvation or mutations that alter Pi homeostasis in two model plants, rice and Arabidopsis, and found that xylem parenchyma cells and basal node sieve tube element cells play a critical role in Pi homeostasis in rice. We also used IOSA to screen for mutants altered in cellular Pi homeostasis. From this, we have identified a novel cellular Pi distribution regulator, HPA1/PHO1;1, specifically expressed in the companion and xylem parenchyma cells regulating phloem Pi translocation from the leaf tip to the leaf base in rice. Taken together, IOSA provides a powerful method for visualizing cellular Pi distribution and facilitates the analysis of Pi signalling and homeostasis from the level of the cell to the whole plant.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Oryza , Fosfatos/metabolismo , Brotos de Planta/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Homeostase/fisiologia , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/metabolismo , Oryza/genética , Oryza/metabolismo
16.
New Phytol ; 242(4): 1576-1588, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38173184

RESUMO

Phosphorus (P) for carbon (C) exchange is the pivotal function of arbuscular mycorrhiza (AM), but how this exchange varies with soil P availability and among co-occurring plants in complex communities is still largely unknown. We collected intact plant communities in two regions differing c. 10-fold in labile inorganic P. After a 2-month glasshouse incubation, we measured 32P transfer from AM fungi (AMF) to shoots and 13C transfer from shoots to AMF using an AMF-specific fatty acid. AMF communities were assessed using molecular methods. AMF delivered a larger proportion of total shoot P in communities from high-P soils despite similar 13C allocation to AMF in roots and soil. Within communities, 13C concentration in AMF was consistently higher in grass than in blanketflower (Gaillardia aristata Pursh) roots, that is P appeared more costly for grasses. This coincided with differences in AMF taxa composition and a trend of more vesicles (storage structures) but fewer arbuscules (exchange structures) in grass roots. Additionally, 32P-for-13C exchange ratios increased with soil P for blanketflower but not grasses. Contrary to predictions, AMF transferred proportionally more P to plants in communities from high-P soils. However, the 32P-for-13C exchange differed among co-occurring plants, suggesting differential regulation of the AM symbiosis.


Assuntos
Carbono , Micorrizas , Fósforo , Solo , Micorrizas/fisiologia , Micorrizas/metabolismo , Fósforo/metabolismo , Carbono/metabolismo , Solo/química , Brotos de Planta/metabolismo , Raízes de Plantas/microbiologia , Raízes de Plantas/metabolismo , Isótopos de Carbono , Plantas/metabolismo , Plantas/microbiologia , Meio Ambiente , Poaceae/metabolismo
17.
Cryobiology ; 114: 104846, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38295926

RESUMO

Petunia × Calibrachoa 'Light Yellow' (× Petchoa 'Light Yellow') is a kind of perennial herbaceous flower obtained through intergeneric hybridization of Petunia and Calibrachoa with high ornamental value and wide application, facing challenges in seed acquisition. Expanding propagation through tissue culture is an economically efficient means. Hence, establishing an effective procedure for the storage of callus is essential for × Petchoa 'Light Yellow'. Cryopreservation is an effective method for the in vitro propagation and long-term preservation of × Petchoa 'Light Yellow' germplasms. For formulating the optimization of the vitrification procedure, first, an orthogonal experimental design was employed to pinpoint critical steps in the vitrification protocol (pre-culture, osmoprotection, dehydration, and dilution) for Petunia × Calibrachoa callus tissues and then five additional factors (pre-culture, osmoprotection I and II, dehydration, and dilution) were optimized to further reduce the sample water content and enhance cell viability levels. The vitrification procedure was described as follows: callus tissues were precultured in MS solid medium with 0.3 M sucrose for 5 d, incubated with osmoprotection solution I and II for 15 min at 25 °C, respectively, cryoprotected with PVS2 for 30 min at 0 °C, and rapidly immersed in liquid nitrogen. Cryopreserved callus tissues were then diluted in MS liquid medium with 1.2 M sucrose for 20 min at 25 °C and recovered on MS solid medium with 0.5 mg/L 6-BA and 0.1 mg/L NAA, and sucrose. The cell viability measured by TTC staining was approximately 16 %-18 % after 72 h-recovery. Following 45 days, the relative survival of callus reached up to 49.48 %. Furthermore, EST-SSR analysis showed no significant difference in the genetic stability of cryopreserved callus compared to the control. Based on the cryopreservation of × Petchoa 'Light Yellow' callus, we further evaluated the response of callus water contents to the osmotic stress in the optimized and original protocols (CK) for a higher cryopreservation survival. A comparative analysis of water content demonstrated that the procedure of gradual and gentle dehydration significantly improved water content and cell survival. Ultrastructural changes between cryopreserved and non-cryopreserved callus were examined and high vacuolation emerged as a key determinant, indicating its substantial impact on the low survival of cryopreserved cells, which should help us to understand the effectiveness of osmotic protectants in dehydration.


Assuntos
Criopreservação , Petunia , Criopreservação/métodos , Crioprotetores/farmacologia , Desidratação , Vitrificação , Sacarose , Água , Brotos de Planta/fisiologia
18.
Recent Pat Biotechnol ; 18(1): 63-70, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37073147

RESUMO

BACKGROUND: Citrus cultivar improvement via conventional breeding strategies is impeded by factors related to its reproductive biology. The orange is a hybrid between pomelo (Citrus maxima) and mandarin (Citrus reticulata). Among various orange cultivars, Valencia oranges have a bit of bitter tang mixed in with their sweetness, as Navel oranges are, the most widely cultivated citrus species, quite sweeter, and also don't contain any seeds. Tangelo mandarin orange cultivar is a hybrid of C. reticulata × C. maxima or × C. paradisi. OBJECTIVE: The present study was undertaken to optimize the hormonal composition of the media with regard to plant growth regulators for in vitro propagation of sweet orange cultivars from nodal segment explants. METHODS: The nodal segment explants were collected from three citrus cultivars, Washington Navel, Valencia and Tangelo. Murashige and Skoog (MS) medium supplemented with sucrose and different concentrations of growth regulators was used for shoot proliferation and root induction, and the optimum medium composition was assessed. The patent for Citrus Tissue Culture was obtained from the Office of Research Affairs, Haramaya University. RESULTS: The results indicate that the highest shoot response was recorded for Washington's navel with maximum shoot proliferation rate (99.75%), shoot number per explant (1.76), shoot length (10.70 cm), leaf number per explants (3.54) after three weeks of culture. In all experiments, no growth was observed for the basal MS medium. Phytohormone combinations of IAA (1.2 mg/L) and kinetin (2.0 mg/L) were found to be the best for shoot proliferation. Among the cultivars, there were significant differences for the highest rooting rate (81.255), root number (2.22), and root length (2.95 cm) variables for Washington Navel. The lowest rooting rate (48.45%), root number (1.47) and root length (2.26 cm) were observed for Valencia. The highest rooting rate (84.90%), root number per microshoot (2.22) and root length (3.05 cm) was on MS medium supplemented with 1.5 mg/L NAA. CONCLUSION: A comparison of different concentrations of IAA and NAA on root induction of microshoots from nodal segments of citrus cultivars demonstrated NAA was a more effective hormone than IAA.


Assuntos
Citrus , Humanos , Brotos de Planta , Patentes como Assunto , Reguladores de Crescimento de Plantas/farmacologia , Cinetina
19.
Plant Cell Environ ; 47(2): 429-441, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37916615

RESUMO

The ratio of red light to far-red light (R:FR) is perceived by light receptors and consequently regulates plant architecture. Regulation of shoot branching by R:FR ratio involves plant hormones. However, the roles of strigolactone (SL), the key shoot branching hormone and the interplay of different hormones in the light regulation of shoot branching in tomato (Solanum lycopersicum) are elusive. Here, we found that defects in SL synthesis genes CAROTENOID CLEAVAGE DIOXYGENASE 7 (CCD7) and CCD8 in tomato resulted in more lateral bud growth but failed to reverse the FR inhibition of lateral bud growth, which was associated with increased auxin synthesis and decreased synthesis of cytokinin (CK) and brassinosteroid (BR). Treatment of auxin also inhibited shoot branching in ccd mutants. However, CK released the FR inhibition of lateral bud growth in ccd mutants, concomitant with the upregulation of BR synthesis genes. Furthermore, plants that overexpressed BR synthesis gene showed more lateral bud growth and the shoot branching was less sensitive to the low R:FR ratio. The results indicate that SL synthesis is dispensable for light regulation of shoot branching in tomato. Auxin mediates the response to R:FR ratio to regulate shoot branching by suppressing CK and BR synthesis.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Brotos de Planta/metabolismo , Citocininas , Lactonas , Ácidos Indolacéticos , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
20.
New Phytol ; 241(2): 553-559, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37984062

RESUMO

Decades of research have primarily emphasized genetic blueprint as the driving force behind plant regeneration. The flow of information from genetics, which manifests as biochemical properties, including hormones, has been extensively implicated in plant regeneration. However, recent advancements have unveiled additional intrinsic modules within this information flow. Here, we explore the three core modules of plant regeneration: biochemical properties, mechanical forces acting on cells, and cell geometry. We debate their roles and interactions during morphogenesis, emphasizing the potential for multiple feedbacks between these core modules to drive pattern formation during regeneration. We propose that de novo organ regeneration is a self-organized event driven by multidirectional information flow between these core modules.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Brotos de Planta/metabolismo , Retroalimentação , Morfogênese , Regulação da Expressão Gênica de Plantas
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