Seasonal fluctuations in day length regulate important aspects of plant development such as the flowering transition or, in potato (Solanum tuberosum), the formation of tubers. Day length is sensed ...by the leaves, which produce a mobile signal transported to the shoot apex or underground stems to induce a flowering transition or, respectively, a tuberization transition. Work in Arabidopsis, tomato and rice (Oryza sativa) identified the mobile FLOWERING LOCUS T (FT) protein as a main component of the long-range 'florigen', or flowering hormone, signal. Here we show that expression of the Hd3a gene, the FT orthologue in rice, induces strict short-day potato types to tuberize in long days. Tuber induction is graft transmissible and the Hd3a-GFP protein is detected in the stolons of grafted plants, transport of the fusion protein thus correlating with tuber formation. We provide evidence showing that the potato floral and tuberization transitions are controlled by two different FT-like paralogues (StSP3D and StSP6A) that respond to independent environmental cues, and show that an autorelay mechanism involving CONSTANS modulates expression of the tuberization-control StSP6A gene.
To improve the production of yerba mate seedlings by increasing rooting rates, clonal propagation is used, especially the mini-cutting technique, which aims to increase genetic gains and production ...efficiency. Thus, the objective was to evaluate the influence of different sizes of mini-cuttings and successive collections on the rooting and root vigor of Ilex paraguariensis. Four successive collections were carried out and mini-cuttings measuring 4, 6, 8 and 10 cm (± 0.2) in length were made, which were staked in 110 cm 3 tubes and kept in a climate-controlled greenhouse for 45 days. Rooting percentage, number of mini-cutting roots -1 , average length of the three largest mini-cutting roots -1, callus, mortality, survival, and maintenance of original leaves were considered. Rooting was influenced by the size of the mini-cuttings, with mini-cuttings of 8 cm and 10 cm showing greater vigor. The good adaptation of the mini-stumps tends to favor the rooting of the mini-cuttings throughout the collections, showing the potential of the mini-cutting technique for the vegetative influence of Ilex paraguariensis.
The E. stipitata is a native fruit tree from the Amazon, currently in the domestication phase due to its high nutritional and economic potential. In this process, studies aiming at the technical ...feasibility of propagating materials with desirable agronomic qualities are necessary but still incipient. Thus, the objective of this study was to evaluate different grafting methods forE. stipitata propagation and the compatibility between scion and rootstock using anatomical analysis as a tool. For the experiment, a randomized block design was used in a split-plot scheme over time, with three replications. The plots consisted of three grafting types: cleft grafting, side-veneer grafting, and budding. The subplots were four evaluation times: 30, 60, 90, and 120 days after grafting (DAG). The evaluated variables were the grafting success rate, the number of shoots per graft, shoot length, and shoot diameter. There was a significant interaction between the factors under study. During the experimental period, an increasing grafting success rate and the number of shoots emitted were observed for budding, although with a low success rate. Through cleft grafting, there was a complete loss of shoots at 120 DAG, leading to the subsequent death of all tissues. Budding grafting appears as a promising method for E. stipitata propagation, demonstrating vascular tissue connection feasibility, although this effect did not reflect in the grafting success rate.
Grafting is an ancient cloning method that has been used widely for thousands of years in agricultural practices. Graft-union development is also an intricate process that involves substantial ...changes such as organ regeneration and genetic material exchange. However, the molecular mechanisms for graft-union development are still largely unknown. Here, a micrografting method that has been used widely in Arabidopsis was improved to adapt it a smooth procedure to facilitate sample analysis and to allow it to easily be applied to various dicotyledonous plants. The developmental stage of the graft union was characterized based on this method. Histological analysis suggested that the transport activities of vasculature were recovered at 3 days after grafting (dag) and that auxin modulated the vascular reconnection at 2 dag. Microarray data revealed a signal-exchange process between cells of the scion and stock at 1 dag, which re-established the communication network in the graft union. This process was concomitant with the clearing of cell debris, and both processes were initiated by a wound-induced programme. The results demonstrate the feasibility and potential power of investigating various plant developmental processes by this method, and represent a primary and significant step in interpretation of the molecular mechanisms underlying graft-union development.
Roses are one of the oldest and perhaps most noble and beautiful plants in the world. The propagation of roses by stem cutting is the simplest and a largely used method to multiply them. For the ...present experiment, seven varieties of roses were selected as follows: ‘Monika’, ‘Mr. Lincoln’, ‘Queen Elisabeth’, ‘The Fairy’, ‘Peace’, ‘King’s Ransom’, and ‘Don Juan’. To assess the differences between the varieties, growth, root length, root number, and frost damage were determined. The aim of the experiment is to determine which rose varieties are better suited to propagation by cuttings, which varieties have a higher rooting tendency, and to what extent the rooting could be influenced by rooting hormones Incit-8 (0.8% of 1-Naphthaleneacetic acid) and Radi-Stim
. From our results, it could be determined that the Incit-8 positively influenced the number of roots of all varieties. In conclusion, our research suggests that the rooting hormones increase the rooting of the rose varieties; moreover, that proper rooting could also be depending on the appropriate conditions.
Abstract
Adventitious rooting is an essential step in vegetative propagation. Currently, the mechanism that regulates adventitious root (AR) development in woody plants is poorly understood. This ...work demonstrates that Populus tomentosa WUSCHEL-related homeobox 5a (PtoWOX5a) transcription factor is involved in AR development in poplar. PtoWOX5a was specifically expressed in the AR tip and lateral root tip during AR and lateral root regeneration from the stem segment. Phenotypic complementation experiments indicated that the PtoWOX5a can functionally complement AtWOX5 in quiescent center (QC) cells. Overexpression of PtoWOX5a introduces significant developmental phenotypes in roots and leaves, such as increased AR number, decreased AR length, swollen AR tip and lateral root tip, and decreased leaf number and area. The conserved mechanism of D-type cyclins (CYCD) repression mediated by WOX5 was confirmed in poplar. The co-expression network of PtWOX5a was constructed, which provided clues to reveal the molecular mechanism of PtoWOX5a in AR development in poplar. Taken together, our results suggest that the PtoWOX5a is involved in AR development though cooperating with a series of functional genes.
Razmnoževanje s potaknjenci je najpomembnejša in najpogosteje uporabljena metoda vegetativnega razmnoževanja rastlin v okrasnem vrtnarstvu. V verigi proizvodnje sadik se pridelovalci poslužujejo ...različnih tehnik in metod, da bi zagotovili oziroma ohranili karseda kakovosten rastlinski material. Zaradi selitve večjih svetovnih pridelovalcev zelnatih okrasnih rastlin v tropska in subtropska območja, kjer je pridelava enostavnejša, cenejša in lažja, je ohranjanje kakovosti materiala v času transporta postalo ključnega pomena za nadaljnjo proizvodnjo rastlin. Metoda hladnega skladiščenja se uporablja pri vegetativnem razmnoževanju in pri transportu potaknjencev zelnatih in lesnatih okrasnih rastlin iz ekvatorialnih delov do območij, kjer jih nato koreninijo. Hladno skladiščenje zniža temperaturo rastlinskega materiala, posledično se upočasni metabolizem rastlin med skladiščenjem, ohrani se rastni potencial in kakovost potaknjencev ter podaljša se njihovo obstojnost. V prispevku je predstavljen pregled na področju hladnega skladiščenja potaknjencev različnih vrst okrasnih rastlin, s poudarkom na potaknjencih zelnatih, lesnatih rastlin in rastlin iz in vitro proizvodnje.
Vegetatively propagated crops are globally significant in terms of current agricultural production, as well as for understanding the long-term history of early agriculture and plant domestication. ...Today, significant field crops include sugarcane (Saccharum officinarum), potato (Solanum tuberosum), manioc (Manihot esculenta), bananas and plantains (Musa cvs), sweet potato (Ipomoea batatas), yams (Dioscorea spp.) and taro (Colocasia esculenta). In comparison with sexually reproduced crops, especially cereals and legumes, the domestication syndrome in vegetatively propagated field crops is poorly defined.
Here, a range of phenotypic traits potentially comprising a syndrome associated with early domestication of vegetatively propagated field crops is proposed, including: mode of reproduction, yield of edible portion, ease of harvesting, defensive adaptations, timing of production and plant architecture. The archaeobotanical visibility of these syndrome traits is considered with a view to the reconstruction of the geographical and historical pathways of domestication for vegetatively propagated field crops in the past.
Although convergent phenotypic traits are identified, none of them are ubiquitous and some are divergent. In contrast to cereals and legumes, several traits seem to represent varying degrees of plastic response to growth environment and practices of cultivation, as opposed to solely morphogenetic 'fixation'.
In environments under chronic human disturbance, the persistence of woody plants via both resprouting of new shoots and clonal growth via new root suckers can increase survival and fitness. However, ...the relative frequency and importance of these mechanisms following disturbance remain poorly explored. Here we simulated both wood extraction (partial aboveground biomass (AGB) removal) and slash-and-burn (complete AGB removal plus burn) practices in situ and compare their effects versus controls after six months on the persistence (resprouting from new shoots and clonal growth via new root suckers), biomass, and structure (height, diameter at ground level, and number of stems) of six dominant tree species (n = 210). Tree regeneration following slash-and-burn varied from 0–80% across species. Half regenerated exclusively via clonal growth, one via resprouting, and one via both mechanisms. Increased disturbance intensity (control < wood extraction < slash-and-burn) resulted in at least fivefold more root suckers produced. Nevertheless, slash-and-burn led to the apparent mortality of nearly 70% of trees (i.e., absence of living aboveground tissue after six months). For those trees that did show evidence of regeneration, initial biomass recovery was nearly 5%, mainly from resprouting of new shoots. Our findings support the presence of persistence mechanisms after human disturbances in a relatively high proportion of woody plant species in the Caatinga dry forest. In the context of limited seed germination and seedling recruitment, resprouting and clonal growth may have a more significant role in regeneration dynamics than previously thought. Regeneration ability must be considered when choosing species for restoration purposes, especially in disturbed landscapes.
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•Woody species can persist via resprouting or root suckers after human disturbances.•Slash-and-burn practice drastically reduce the initial aboveground regeneration.•Human disturbances can alter the physical structure of persisting trees.•More intense human disturbances increase the production of new root suckers.•Only 5% of the lost biomass was recovered after six months, mainly via resprouting.
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