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Adventitious root (AR) formation in excised plant parts is a bottleneck for survival of isolated plant fragments. AR formation plays an important ecological role and is a critical process in cuttings for the clonal propagation of horticultural and forestry crops. Therefore, understanding the regulation of excision-induced AR formation is essential for sustainable and efficient utilization of plant genetic resources. Recent studies of plant transcriptomes, proteomes and metabolomes, and the use of mutants and transgenic lines have significantly expanded our knowledge concerning excision-induced AR formation. Here, we integrate new findings regarding AR formation in the cuttings of diverse plant species. These findings support a new system-oriented concept that the phytohormone-controlled reprogramming and differentiation of particular responsive cells in the cutting base interacts with a co-ordinated reallocation of plant resources within the whole cutting to initiate and drive excision-induced AR formation. Master control by auxin involves diverse transcription factors and mechanically sensitive microtubules, and is further linked to ethylene, jasmonates, cytokinins and strigolactones. Hormone functions seem to involve epigenetic factors and cross-talk with metabolic signals, reflecting the nutrient status of the cutting. By affecting distinct physiological units in the cutting, environmental factors such as light, nitrogen and iron modify the implementation of the genetically controlled root developmental programme. Despite advanced research in the last decade, important questions remain open for future investigations on excision-induced AR formation. These concern the distinct roles and interactions of certain molecular, hormonal and metabolic factors, as well as the functional equilibrium of the whole cutting in a complex environment. Starting from model plants, cell type- and phase-specific monitoring of controlling processes and modification of gene expression are promising methodologies that, however, need to be integrated into a coherent model of the whole system, before research findings can be translated to other crops.

This paper presents a proposal for a flying-cutting plant designed using the SketchUp tool for 3D modeling and constructed with electronic devices and other low-cost components. The proposed prototype aims to facilitate the implementation of control strategies in academic settings, such as laboratory practices. The primary contribution of this work is the development of a scaled,cost-effective industrial prototype that can be operated and controlled using various software and hardware tools. The plant features a conveyor belt and a mechanical arm for continuous cutting, enabling it to emulate the operation of large-scale industrial processes. To validate the design, the plant was simulated using a continuous and discrete transfer function as its mathematical representation, obtained through an identification process performed with MATLAB’s PID Tuner. Performance testswere then conducted using tools such as Simulink and Code Composer Studio by Texas Instruments. After validation, operation and shear tests were carried out on the physical prototype, employing a classical control technique. Una propuesta de planta de corte al vuelo es presentada en este artículo. La planta fue diseñada usando la herramienta SketchUp para modelado 3D y construida usando dispositivos electrónicos y otros elementos de bajo costo. El propósito del prototipo propuesto centra su aplicación en entornos académicos a través del desarrollo de estrategias de control en prácticas de laboratorio. Una contribución importante del trabajo realizado estuvo en el diseño de un prototipo industrial a escala y de bajo costo, que brinda la posibilidad de ser operado y controlado a través de diferentes sistemas embebidos que integran elementos tanto a nivel de software como de hardware. La planta cuenta con una banda transportadora y un brazo mecánico para corte continuo que permite emular el funcionamiento de procesos industriales de gran escala. Como resultados, se realizaron simulación de la planta mediante una función de transferencia continua y discreta como representación matemática, la cual fue obtenida a través de un proceso de identificación realizado en PIDTuner de MATLAB. Posteriormente, se realizaron pruebas de desempeño a través de herramientas como Simulink y Code Composer Studio de Texas Instruments y, una vez validado su funcionamiento, se implementaron pruebas de operación y de corte en el prototipo construido empleando una técnica de control clásica. Uma proposta de planta de corte em voo é apresentada neste artigo. A planta foi projetada utilizando a ferramenta SketchUp para modelagem 3D e construída com dispositivos eletrônicos e outros elementos de baixo custo. O propósito do protótipo proposto centra sua aplicação em ambientes acadêmicos por meio do desenvolvimento de estratégias de controle em práticas de laboratório. Uma contribuição importante do trabalho realizado foi o design de um protótipo industrial em escala e de baixo custo, que possibilita sua operação e controle através de diferentes sistemas embarcadosque integram elementos tanto de software quanto de hardware. A planta conta com uma esteiratransportadora e um braço mecânico para corte contínuo, permitindo emular o funcionamento de processos industriais de grande escala. Como resultados, foram realizadas simulações da planta por meio de uma função de transferência contínua e discreta como representação matemática, obtida através de um processo de identificação realizado no pidt uner do matlab . Posteriormente, foram conduzidos testes de desempenho utilizando ferramentas como Simulink e Code Composer Studio da Texas Instruments e, após a validação de seu funcionamento, foram implementados testes de operação e corte no protótipo construído, empregando uma técnica de controle clássica.

Background Adventitious root (AR) formation is a critical developmental process in cutting propagation for the horticultural industry. While auxin has been shown to regulate this process, the exact mechanism and details preceding AR formation remain unclear. Even though AR and lateral root (LR) formation share common developmental processes, there are exist some differences that need to be closely examined at the cytological level. Tomato stem cuttings, which readily form adventitious roots, represent the perfect system to study the influence of auxin on AR formation and to compare AR and LR organogenesis. Results Here we show the progression by which AR form from founder cells in the basal pericycle cell layers in tomato stem cuttings. The first disordered clumps of cells assumed a dome shape that later differentiated into functional AR cell layers. Further growth resulted in emergence of mature AR through the epidermis following programmed cell death of epidermal cells. Auxin and ethylene levels increased in the basal stem cutting within 1 h. Tomato lines expressing the auxin response element DR5pro:YFP showed an increase in auxin distribution during the AR initiation phase, and was mainly concentrated in the meristematic cells of the developing AR. Treatment of stem cuttings with auxin, increased the number of AR primordia and the length of AR, while stem cuttings treated with the pre-emergent herbicide/auxin transport inhibitor N-1-naphthylphthalamic acid (NPA) occasionally developed thick, agravitropic AR. Hormone profile analyses showed that auxin positively regulated AR formation, whereas perturbations to zeatin, salicylic acid, and abscisic acid homeostasis suggested minor roles during tomato stem rooting. The gene expression of specific auxin transporters increased during specific developmental phases of AR formation. Conclusion These data show that AR formation in tomato stems is a complex process. Upon perception of a wounding stimulus, expression of auxin transporter genes and accumulation of auxin at founder cell initiation sites in pericycle cell layers and later in the meristematic cells of the AR primordia were observed. A clear understanding and documentation of these events in tomato is critical to resolve AR formation in recalcitrant species like hardwoods and improve stem cutting propagation efficiency and effectiveness.

The dried fig cv. Sabz of Iran, distinguishes out among the several fig cultivars for its unique characteristics and excellent properties. The aims to this study were 1) Carefully monitoring the resulting phenotypic changes in growth patterns, leaf morphology, shoot traits, root characteristics, and other relevant traits after irradiated with different gamma rays; 2) Investigating the LD.sub.25, .sub.50, .sub.75 and GR.sub.25, .sub.50, .sub.75 values at different gamma radiation doses for chose optimum dose. According to our results, the LD.sub.50 was 70 Gy, while the LD.sub.25 and LD.sub.75 were approximately 48 and 95 Gy, respectively. Data analysis revealed that higher doses, ranging from 50 to 90 Gy, led to a reduction in leaf area for fig hardwood cuttings compared to those exposed to lower doses of gamma irradiation (10, 20, 30, and 40 Gy). In fig cuttings, the plant height gradually decreased in line with increasing irradiation doses up to 60 Gy. Among the root traits, root number was particularly influenced by higher radiation doses. On other hand, when fig cuttings were exposed to a 40 Gy radiation dosage, the average root count dropped by 50%. However, when fig cuttings were subjected to a 90 Gy radiation dose, the average root count surged by 90.7% in comparison to the control treatment. Additionally, the GR.sub.50 values were 63 Gy for internode length, 67 Gy for leaf area and 56 Gy for plant height and aerial biomass. However, the GR.sub.50 values for root number, root volume, and root biomass were 46 Gy, 57 Gy, and 51 Gy, respectively. An analysis based on the GR.sub.25, GR.sub.50, and GR.sub.75 values indicated that plant height, aerial biomass and root biomass exhibited greater sensitivity to radioactivity in comparison to other plant portions of the fig. According to the biological responses in the 'Sabz' fig, 60 Gy of gamma radiation is a suitable dose for initial mutagenesis studies.