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Rejuvenation and Adventitious Rooting in Coppice-Shoot Cuttings of Tectona grandis as Affected by Stock-Plant Etiolation  [PDF]
Azamal Husen
American Journal of Plant Sciences (AJPS) , 2011, DOI: 10.4236/ajps.2011.23042
Abstract: The effect of stock-plant etiolation on adventitious rooting of single-node leafy cuttings (SNCs) made from coppice shoots from different age groups of donor plants were investigated for teak (Tectona grandis Linn. f.). When donor plants age were 1-, 2-, 3-, 4-, and 5-year-old, they were coppiced and maintained in the dark for etiolation, while a parallel set was kept in normal light in an open environment. After 20 days, coppice shoots were made into SNCs which were cultured under intermittent mist for rooting. Stock-plant etiolation significantly increased percent rooting, shoot and root length, and number of roots per SNC, but callusing at the base of SNCs decreased. Etiolated SNCs have shown 71.7% rooting, whereas for controls (non-etiolated), the response was 41.7%. The effect of aging on callusing, rooting and sprouting of etiolated and non-etiolated coppice shoots cuttings varied widely. Aging of donor plants decreased rooting and sprouting capability in SNCs and increased callusing at the base of etiolated cuttings. The results showed that stock-plant etiolation in 1-, 2-, 3-, 4-, and 5-year-old donor plants hastened rooting potential by rejuvenation of coppice shoots.
Role of Anthraquinones as a Marker of Juvenility and Maturity in Response to Adventitious Rooting of Tectona grandis  [PDF]
Azamal Husen,Sayyada Khatoon
American Journal of Plant Physiology , 2012,
Abstract: Adventitious root formation in woody plants is highly influenced by the process of physiological ageing. There are increasing efforts to identify markers for distinguishing between mature and juvenile stages of trees. However, it appears to be very little information on this aspect at the chemical and molecular levels. The aim of the work was to identify potential chemical marker of juvenile and mature state; and accomplish maximum rooting in teak (Tectona grandis Linn. f.) leafy shoot cuttings. Experiments with teak leafy shoot cuttings of three different physiological ages 30- and 15-year-old (mature); and 2-month-old (juvenile) were conducted in mist propagation system. Maturity of donor teak plants decreased rooting ability. Cuttings obtained from 2-month-old donors rooted more profusely in comparison to 15- and 30-year-old donors. Indole-3-butyric acid treatment at 4000 mg L-1 significantly increased rooting percentage and produced highest number of roots. High Performance Thin Layer Chromatography (HPTLC) analysis of anthraquinones (AQs; C14H8O2) was utilized to detect qualitative and quantitative differences in AQs in stem tissues from 2-month, 15- and 30-year-old donor plants. The HPTLC analysis showed that AQs varied from 2.8 to 18.3% in cuttings derived from 2-month-old donor plants, while the variations were 4.9 to 27.3% and 11.8 to 43.4% in those from 15- and 30-year-old donor plants, respectively. Altogether, data support that AQs could be a reliable marker for maturity vis-à-vis juvenility in teak.
Stakeholder analysis for coppice forestry in Bulgaria  [PDF]
IvayloVelichkov,Tzvetan Zlatanov,Georgi Hinkov
Annals of Forest Research , 2009,
Abstract: The study analyzes the state of coppice forestry in Bulgaria during last 18 years. Stakeholders and their interests and preferences in coppice forests are explored and assessed. Forests restitution process in Bulgaria started in 1997 and has not been finished yet. Nevertheless, significant further changes of the current ownershipdistribution are not expected. By the end of 2007, the state was the biggest coppice forest owner/stakeholder in Bulgaria with 71.3% of all coppice forests being state property. The other two important stakeholders are the municipalities (14.0%) and private owners (12.0%). Currently, forest owners' number in Bulgaria exceeds 1million, the average holding area being smaller than 1 ha. Only 150 individual plots are larger than 50 ha. The majority of private owners aim at taking maximum and immediate profit from their recently restituted forest properties. In most cases that reflects in clearcuts. Coppice forests management has been one of the problematicissues of Bulgarian forestry for decades. Despite of forest authorities significant efforts, the area of coppice forests in Bulgaria (1.78 million ha in 2007) remained unchanged for a period of 50 years. The official forest policy is still aimed at conversionof coppice forests into seed ones through different silvicultural methods. That policy is applied to almost all coppice forests regardless of their ownership.
Energy dissipation of rockfalls by coppice structures
G. Ciabocco, L. Boccia,M. N. Ripa
Natural Hazards and Earth System Sciences (NHESS) & Discussions (NHESSD) , 2009,
Abstract: The objective of this work is to develop elements to improve understanding of the behaviour of a coppice in relation to the phenomenon of falling boulders. The first section proposes an amendment to the equation for calculating the index which describes the probability of impact between a rock and plants in managed coppice forests. A study was carried out, using models to calculate the kinetic energy of a falling boulder along a slope considering the kinetic energy dissipated during the impact with the structure of forest plants managed by coppice. The output of the simulation models were then compared with the real dynamics of falling boulders in field tests using digital video. It emerged from an analysis of the results of this comparison that a modification to the 1989 Gsteiger equation was required, in order to calculate the "Average Distance between Contacts" (ADC). To this purpose, the concept of "Structure of Interception", proposed in this paper, was developed, valid as a first approach for describing the differences in the spatial distribution of stems between coppice and forest. This study also aims to provide suggestions for forestry management, in order to maintain or increase the protective capacity of a coppice managed with conventional techniques for the area studied, modifying the dendrometric characteristics.
Adventitious Roots and Secondary Metabolism
Hosakatte Niranjana Murthy,Eun Joo Hahn,Kee Yoeup Paek,
Hosakatte Niranjana Murthy
,Eun Joo Hahn,Kee Yoeup Paek

生物工程学报 , 2008,
Abstract: Plants are a rich source of valuable secondary metabolites and in the recent years plant cell, tissue and organ cultures have been developed as an important alternative sources for the production of these compounds. Adventitious roots have been successfully induced in many plant species and cultured for the production of high value secondary metabolites of pharmaceutical, nutraceutical and industrial importance. Adoption of elicitation methods have shown improved synthesis of secondary metabolites in adventitious root cultures. Development of large-scale culture methods using bioreactors has opened up feasibilities of production of secondary metabolites at the industrial levels. In the present review we summarize the progress made in recent past in the area of adventitious root cultures for the production of secondary metabolites.
Residual effect of growth regulators in etiolation and regeneration of in vitro pineapple plants
Souza, Fernanda Vidigal Duarte;Canto, Ana Maria Mascarenhas Eloy;Souza, Ant?nio da Silva;Costa, Maria Angélica Pereira de Carvalho;
Revista Brasileira de Fruticultura , 2010, DOI: 10.1590/S0100-29452010005000075
Abstract: this work aimed to evaluate the influence of naphthaleneacetic acid (naa) and gibberellic acid (ga3) plant regulators in in vitro etiolation and subsequent regeneration of the pe x sc-60 pineapple hybrid. nodal segments of in vitro plants with approximately 5-7 cm height were incubated in basic ms culture medium supplemented with 0.0; 0.5 and 1.0 mg l-1 of naphthaleneacetic acid (naa) in combination with gibberellic acid (ga3) in concentrations of 0.0; 0.5 and 1.0 mg l-1, and maintained at 27 oc under dark condition. evaluations were carried out at 90 and 180 days after incubation period. the best results for length of etiolated stems were obtained with 1.0 mg l-1 of naa. in the experiment followed by the regeneration, stems with 3 cm from the etiolation treatment, were cultivated in proliferation medium and the number of regenerated plants per treatment was evaluated at 60 days of cultivation. the treatment that promoted the best etiolation of plants also promoted the worst regeneration rates, demonstrating the residual effect of the auxin used in the previous step in the regeneration of plants of the pineapple hybrid evaluated.
Rejuvenation in the Random Energy Model  [PDF]
Marta Sales,Jean-Philippe Bouchaud
Physics , 2001, DOI: 10.1209/epl/i2001-00111-0
Abstract: We show that the Random Energy Model has interesting rejuvenation properties in its frozen phase. Different `susceptibilities' to temperature changes, for the free-energy and for other (`magnetic') observables, can be computed exactly. These susceptibilities diverge at the transition temperature, as (1-T/T_c)^-3 for the free-energy.
Optimised Migrate Virtual Machine Rejuvenation  [PDF]
Sanheji Manel, Azizi Ridha, Maaloul Alia
Journal of Computer and Communications (JCC) , 2015, DOI: 10.4236/jcc.2015.38004
Abstract: Server virtualization is an essential component in virtualized software infrastructure such as cloud computing. Virtual machines are generated through a software called virtual machine monitor (VMM) running on physical servers. The risks of software aging caused by aging-related bugs affect both VM and VMM. As a result, service reliability degrades may generate huge financial losses to companies. This paper presents an analytic model using stochastic reward nets for time-based rejuvenation techniques of VMM and VM. We propose to manipulate the VM behavior while the VMM rejuvenation is according to the load on the system. Using a previous Petri net model of virtualized server, we performed an algorithm in order to optimize rejuvenation technique and achieve high availability. So we perform Migrate-VM rejuvenation or Warm-VM rejuvenation while there are current jobs in the system. Although Migrate-VM rejuvenation is better than Warm-VM rejuvenation in steady state availability, it can’t be always performed as it depends on the capacity of the other host. When the queue is empty and the virtual machine has no current jobs to serve, we propose to combine both VMM rejuvenation and VM rejuvenation. We show that the proposed technique can enhance the availability of VMs.
Productivity of Processing Hardwood from Coppice Forests  [PDF]
Christian Suchomel,Raffaele Spinelli,Natascia Magagnotti
Croatian Journal of Forest Engineering , 2012,
Abstract: Approximately half of the Italian forest area is classified as coppice forest, mostly managed for the production of firewood. Chestnut (Castanea sativaMill.) coppice stands make exception, as they also produce more valuable assortments, such as sawlogs, poles and fencing materials. Hence the significantly higher industrial activity in chestnut coppice stands, and the rapid introduction of mechanized harvesting. This study deals with four different harvester units used for processing (delimbing – bucking) chestnut trees from coppice stands, at the landing. For these four different machines, time studies were conducted in order to estimate productivity and compare the performance. The results show that the processors can reach high productivities (7.7m^3/PMH0–19.8m3/PMH0). In one study the influence of tree form has been estimated, proving that the size of the branches and the shape of the stem have a significant effect on machine productivity. The difference can reach 2.3 m^3/PMH0 for stems with a volume of 0.2 m^3.
Auxin Control in the Formation of Adventitious Roots  [cached]
Tiberia I. POP,Doru PAMFIL,Catherine BELLINI
Notulae Botanicae Horti Agrobotanici Cluj-Napoca , 2011,
Abstract: Adventitious rooting is a complex process and a key step in the vegetative propagation of economically important woody, horticultural and agricultural species, playing an important role in the successful production of elite clones. The formation of adventitious roots is a quantitative genetic trait regulated by both environmental and endogenous factors. Among phytohormones, auxin plays an essential role in regulating roots development and it has been shown to be intimately involved in the process of adventitious rooting. Great progress has been made in elucidating the auxin-induced genes and auxin signaling pathway, especially in auxin response Aux/IAA and Auxin Response Factor gene families. Although some important aspects of adventitious and lateral rooting signaling have been revealed, the intricate signaling network remains poorly understood. This review summarizes some of the current knowledge on the physiological aspects of adventitious root formation and highlights the recent progress made in the identification of putative molecular players involved in the control of adventitious rooting. Despite much has been discovered regarding the effects and regulation of auxins on plant growth since the Darwin experiments, there is much that remains unknown.
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