Soil seed bank of the invasive Robinia pseudoacacia in planted Pinus nigra stands

Pinus nigra and Robinia pseudoacacia are exotic trees used for afforestation in Hungary. Pinus nigra was non-invasive, however R. pseudoacacia escaped from cultivation and invaded several vegetation types including pine plantations. It has recently been planned to cut P. nigra plantations and replace them by native tree stands, especially in nature reserves. The scattered presence of R. pseudoacacia specimens in pine stands might place constraints on planned tree replacement because of their vegetative resprouting and recolonization from an established seed bank. The aim of this study was to investigate the soil seed bank under the canopy of solitary R. pseudoacacia specimens found in P. nigra plantations. Altogether 250 soil samples were collected from the 0–6 and 6–12 cm soil layers under solitary Robinia trees of varying ages (with basal areas between 62.4 and 1089.3 cm2). Seeds were separated by sieving then scarified and germinated. Seed bank density ranged between 640 and 2285 seedsm–2 with an average distribution of 82.7% and 17.3% in the upper and lower soil layer, respectively. Total density of the seed bank and also the seed bank ratio of the lower soil layer increased with tree age. The accumulated seed bank of R. pseudoacacia should be considered in the careful planning of tree replacement operations in Pinus nigra stands

An investigation of latency prediction for NoC-based communication architectures using machine learning techniques

© 2019, Springer Science+Business Media, LLC, part of Springer Nature. Due to the increasing number of cores in Systems on Chip (SoCs), bus architectures have suffered with limitations regarding performance. As applications demand higher bandwidth and lower latencies, buses have not been able to comply with such requirements due to longer wires and increased capacitance. Facing this scenario, Networks on Chip (NoCs) emerged as a way to overcome the limitations found in bus-based systems. Fully exploring all possible NoC characteristics settings is unfeasible due to the vast design space to cover. Therefore, some methods which aim to speed up the design process are needed. In this work, we propose the use of machine learning techniques to optimise NoC architecture components during the design phase. We have investigated the performance of several different ML techniques and selected the Random Forest one targeting audio/video applications. The results have shown an accuracy of up to 90% and 85% for prediction involving arbitration and routing protocols, respectively, and in terms of applications inference, audio/video achieved up to 99%. After this step, we have evaluated other classifiers for each application individually, aiming at finding the adequate one for each situation. The best class of classifiers found was the Tree-based one (Random Forest, Random Tree, and M5P) which is very encouraging, and it points to different approaches from the current state of the art for NoCs latency prediction

Antibacterial activity of seed proteins of Robinia pseudoacacia

A low molecular weight cationic peptide was isolated from Robinia pseudoacacia seed and tested in vitro against seven bacteria (Corynebacterium michiganense, Staphylococcus aureus, Bacillus subtilis, Erwinia carotovora subsp. carotovora, Pseudomonas syringae pv syringae, Xanthomonas campestris pv campestris, and Escherichia coli). The peptide inhibited the growth of the tested strains. The effective concentrations required for 50% inhibition of bacterial growth ranged between 20 and 120 mug ml(-1) protein. S. aureus was found to be the most sensitive strain, however, E. coli was not affected much when compared with others. Reduction of antibacterial activity of the peptide with CaCl2 addition into the growth medium was also observed. (C) 2004 Elsevier B.V. All rights reserved

Effects of brassinosteroid on cotton regeneration via somatic embryogenesis

Brassinolide (BR), which is the most biologically active brassinosteroid, was used to examine the potential effect of hormone on cotton somatic embryogenesis. Ten-day-old cotton (Gossypium hirsutum L, cv. Cooker) seedlings were used for explant source and hypocotyls were removed and cultured on MS basal medium with 135 vitamins supplemented with 1 mg/L 6-benzylaminopurine + 0.5 mg/L kinetin for callus induction. After one month proliferating calli pieces were collected and cultured on MS basal medium containing various concentrations of BR (0.1, 0.5, 1.0 AM) with their controls. BR treatments were negatively effective on the fresh weight of calli when compared to control. Differential somatic embryogenesis maturation rates due to BR treatment were observed. Somatic embryogenesis was stimulated especially for transition to cotyledonary phase at 0.5 mg/L BR. Histological preparations from embryogenic calli and somatic embryos at different stages of development revealed the spontaneous polyploidisation during early somatic embryogenesis on BR-treated calli. Present results suggest that BR negatively effected calli growth, however, had a stimulating role in maturation of somatic embryos

Investigations on biotechnologically developed poplar clones as raw material for pulp and paper industry

In this review an overview of our research on biotechnologically developed poplar clones for application in paper and pulp industry was presented. Nine native clones of Populus tremula as well as five hybrid clones of P. deltoides x P. deltoides were used for establishment of plant tissue culture system. For this purpose 'Woody Plant Medium' (WPM), supplemented with 1 mg/l zeatine (WPMZ) and WPM supplemented with 0.5 mg/l indole-3-butyric acid (IBA) (WPMB), were used for shoot and root regeneration, respectively. Established tissue cultures of poplar clones offer the potential for manipulation with enzymes involved in the lignin biosynthetic pathway such as caffeic acid O-methyltransferase and lignin peroxidases. Poplar clones (89M011, 89M066, Dursunbey 2) with the highest shoot regeneration efficiencies (70-100 %) were used for Agrobacterium transformation with antisense caffeic acid O-methyltransferase (pOMT8) and cationic peroxidase (Shpx6a) genes. Tobacco (Nicotiana tabacum) was used as a model control system. Constructs used in the study were obtained from forage legume Stylosanthes humilis and showed a high homology to corresponding caffeic acid O-methyltransferase (COMT) and peroxidase genes of poplar. Our results showed that antisense pOMT8 and Shpx6a peroxidase genes down regulated the activity of related enzymes. In the pOMT8 transgenics composition of lignin was changed, without changes in amount of lignin. However, in Shpx6a transgenics decreases in amount of lignin (up to 20 %) was observed. In the tobacco experiments with two types of transgenes (pOMT8 and Shpx6a) reduction of related enzymes activities and reduction of lignin amount was occurred in several transgenic plants

Direct plant regeneration from node and apex explants of cotton in Turkey

The objective of this project is to obtain resistance cotton plants to Verticillum dahliae, which is one of the important diseases of cotton in Turkey. One of the method to improve the resistance against such disease is to genetically engineer plants for the expression of antifungal genes (encoding proteins) that are directly toxic to pathogen of interest. Since regeneration protocols for cotton clones from Turkey has not been reported, a shoot regeneration for two important cotton clones (Nazilli M-503 and Sel-5) was developed and presented here. Shoot regeneration from different explants (leaves, petioles, internodes, nodes, hypocotyl and apex) of cotton was investigated on Murashige and Skoog (MS) medium with appropriate supplements of growth regulators. The highest shoot regeneration efficiency was obtained from the nodes and apex explants on MS11 (MS with 2 mg/l zeatin and 2mg/l kinetin) and MS12 (MS with 2 mg/l BAP and 2mg/l zeatin) respectively. Root formation was obtained on MS supplemented with 0.5 mg/l indolebutyric acid (IBA). This regeneration system can be used for further studies on transformation of cotton with antifungal genes