Phytotoxic and cyto-genotoxic activity of essential oil from leaf residues of Eucalyptus urophylla and the hybrid E. urophylla x E. camaldulensis on Lactuca sativa and Sorghum bicolor

The use of agrochemicals has influenced the increase in agricultural productivity. However, the concern about damage to the human health and to the environment, resulting from the indiscriminate use of pesticides, has increased worldwide. Alternative methods for controlling pests and diseases have been proposed to maintain productivity and quality of life. A possibility is to use compounds produced by the secondary metabolism of plants, such as the essential oils. Some of these substances perform inhibitory or stimulatory activity on the development of other organisms. Plants from the genus Eucalyptus have been investigated and were chosen to be studied in the present work, due to the traditional knowledge regarding the potential of the essential oils from some species, as well as, for the need to use residues from their production. Therefore, were determined the yield, identified the compounds from the essential oils of E. urophylla and the hybrid E. urophylla x E. camaldulensis, and evaluated their biological activity through bioassays, investigating the phyto-cyto-genotoxicity and mutagenicity using Lactuca sativa and Sorghum bicolor as model plants. The essential oil from the hybrid provided a higher yield. Eucalyptol was the major compound identified for both oils, representing more than 85% of the compounds present. Both E. urophylla and the hybrid showed phyto-cyto-genotoxic, mutagenic effects, and clastogenic and aneugenic mechanisms of action, promoting epigenetic changes in the meristematic cells of L. sativa. The results point out to the bioherbicidal potential of these essential oils.

Primera localización de un dormidero de milano real Milvus milvus L., 1758 en un eucaliptal en Álava

During the 2020-2021 census to determine the wintering population of Red kite (Milvus milvus) in the Iberian peninsula by counting the number of communal roosts, one such roost was observed in a small reforested area of eucalyptus (genus Eucalyptus) in the northwest of the province of Álava (Basque Country-Spain). Although roosts located on this kind of arboreal substrate are rare, our observation suggests the hypothesis that Red kites will use eucalyptus if the atmospheric conditions are particularly adverse. Therefore, we propose that the distribution and winter ecology of Iberian breeding populations of Red kite be clarified with urgency, the study of which is hampered by the arrival of a multitude of conspecifics of central and northern-European origin in winter

Pollen management and controlled pollination in Eucalyptus urophylla

The genus Eucalyptus has shown great potential for the establishment of commercial forest plantations, it is one of the most widely planted worldwide, it is planted in different regions of the planet, which indicates its ability to adapt to various environmental conditions. Eucalyptus urophylla is a species of this genus that adapts to tropical and subtropical regions, in suitable sites it can achieve high growth rates. It is one of the species with the most research in breeding programs in the world, mainly due to its capacity to hybridize naturally, since it generates populations with high genetic diversity, coupled with its ability to reproduce asexually. In Mexico, the breeding programs for Eucalyptus urophylla are in the initial phase, although plantations are already managed under clonal silviculture, controlled crossing are just beginning, so pollen management and crossing techniques are the most important activities in these programs. Since there is currently no information about the management of pollen for Eucalyptus urophylla in Mexico, the aim of this paper is to show a methodology based on the information documented in other parts of the world and the recent experience acquired in the collection and management of pollen, as well as the controlled pollination techniques recently employed in the breeding programs of Eucalyptus urophylla in southeastern Mexico.

Length variation of chloroplast simple sequence repeats in the genus Eucalyptus L'Hér.

Eucalyptus L'Hér. is an economically important genus of plants with several environmental significances and great industrial advantages. To accelerate breeding and conservation studies, efforts on molecular breeding and molecular genetic analysis are underway in the genus Eucalyptus. Despite these efforts, no sufficient information is available about common, polymorphic and unique chloroplast simple sequence repeats (cpSSRs) in the genus Eucalyptus. . These repeats consist of 1-6 nucleotides and play important role in the development of molecular markers, genetic mapping and plant breeding. In the present study, a total of 920 cpSSRs were detected and length variation of cpSSRs analysed between each pair of species among 31 chloroplast genome sequences of the genus Eucalyptus. Additionally, cross species transferability of common and polymorphic cpSSRs were also observed. The common, unique and putative polymorphic cpSSRs analysed in this study can be used for species identification and genetic diversity studies of Eucalyptus.

The Essential oil of Eucalyptus alba L. Growing on the Salt Zone of Fatick (Senegal) as a Source of 1,8Cineole and Their Antibacterial Activity

Members of the genus Eucalyptus are potential sources of number of commercial essential oils and aromachemicals. In present study, the essential oils isolated by hydrodistillation from the leaves of Eucalyptus alba were analyzed by GC-FID and GC-MS. Essential oil yields ranged from 2.41 to 4.35%. In total 18 constituents were identified, accounting for 99.0 to 99.7% of the total compositions. 1,8-cineole was present in all samples as the major component (76.5-88.1%). In addition to this compound, others that were found including limonene (3.8–8.6%), α-terpineol (1.4–2.8%), globulol (1.3–6.3%) and α-pinene (1.5–1.8%). The essential oil showed a strong antibacterial activity against S. aureus ATCC 29213 which is translated by an MIC of 1.25 mg/mL and good activity against E. coli ATCC 25922 (6.25 mg/mL) and E. faecalis ATCC 29212 (6.25 mg/mL). To our knowledge, our study is the first report of E. alba essential oils characterized by a high 1,8-cineole content (>76.5%). They may have potential applications in food and pharmaceutical products. Keywords: Eucalyptus alba, essential oils, antibacterial activity, 1,8-cineole and GC-SM

Evaluation of the behavior of Eucalyptus clones and Eucalyptus camaldulensis grown in the municipality of Sorriso-MT

The objective of this study was to evaluate the behavior of three hybrids of the genus Eucalyptus and Eucalyptus camaldulensis cultivated at Fazenda Buritis, Sorriso municipality, Mato Grosso State, Brazil, using DAP, height, bark volume, IMA, stem quality and survival. It was done a DIC, distributing 4 plots of 343m2, 49 trees per plot, in each of the 4 cultivated materials in a spacing of 3.5 x 2m, and 3 data collections were carried out, from January 2013 to January 2014 The results show that clones I144 and H13 have higher mean DAP, height, volume with IMA bark, higher percentage of trees with straight stem and higher survival rates indicating that the soil and climatic conditions of the city of Sorriso-MT are presented as suitable for the cultivation of these genetic materials

A entrada na Europa e a expansão inicial do eucalipto em Portugal Continental

Resumo As primeiras observações e recolhas de eucaliptos ocorreram nas grandes viagens inglesas e francesas ao Pacífico, em particular à Austrália, em finais do século XVIII. O género Eucalyptus L'Hér. foi estabelecido em 1788, e logo nas duas décadas seguintes seriam descritas, por botânicos franceses e ingleses, muitas espécies novas. O primeiro eucalipto cultivado em Inglaterra foi trazido, em 1774, na segunda viagem de James Cook. Em França, a introdução terá sido feita em 1804, no Jardim Botânico de Montpellier, na Alemanha em 1809, no Jardim Botânico de Berlim, e em Itália, em 1813, no Jardim Botânico de Nápoles. Em Portugal, a introdução do eucalipto foi muito posterior a estas datas. Na propriedade do duque de Palmela no Lumiar, foram plantados dois eucaliptos em 1850-1852. No Horto Botânico da Escola Médico-Cirúrgica de Lisboa, existia em 1852, pelo menos um espécimen, certamente para uso ou demonstração das suas propriedades terapêuticas. A partir da década de 1860, a expansão foi muito rápida. Em 1869, a companhia real dos caminhos-de-ferro portugueses iniciou a plantação de eucaliptos nas estações, casas de guarda e ao longo da via-férrea. As primeiras plantações em larga escala terão ocorrido na década de 1880 em propriedades perto de Abrantes arrendadas por William T. Tait. Em 1886 estavam já plantados 150 mil eucaliptos. Nesta mesma década começou a plantação, em escala apreciável, de eucaliptos nas Matas Nacionais. Em finais do século XX, tinham sido introduzidas em Portugal cerca de 250 espécies, sendo o Eucalyptus globulus Labill., a espécie largamente dominante. É interessante constatar que tendo sido um dos países europeus que mais tarde introduziu a cultura do eucalipto, Portugal é hoje, a nível mundial, um dos que apresenta maior percentagem da sua área florestal dedicada a esta cultura.Palavras-chave: eucalipto; jardins botânicos; Portugal. Abstract The earliest observations and collections of eucalypts occurred on the great English and French voyages to the Pacific, particularly Australia, in the late 18th century. The genus Eucalyptus L'Hér. was described in 1788, and soon in the following two decades, many species would be described by French and English botanists. The first eucalypt grown in England was brought in 1774 on James Cook's second voyage. In France, the introduction seems to have occurred in 1804, at the Botanical Garden of Montpellier, in Germany in 1809, at the Botanical Garden of Berlin, and in Italy, in 1813, at the Botanical Garden of Naples. In Portugal, the introduction of eucalypts was much later than these dates. In the property of the Duke of Palmela in Lumiar, two eucalypts were planted in 1850-1852. The Botanical Garden of the Medical-Surgical School of Lisbon had in 1852, at least one specimen, certainly for use or demonstration of its therapeutic properties. From the 1860s the expansion was very rapid. In 1869, the royal company of the Portuguese railways began planting eucalypts in the stations, guard houses and along the railroad. The first large-scale plantations occurred in the 1880s in properties near Abrantes leased by William T. Tait. By 1886, 150,000 eucalypts were already planted. In the same decade began the planting, on an appreciable scale, of eucalypts in “Matas Nacionais”. By the end of the 20th century about 250 species had been introduced in Portugal, being Eucalyptus globulus Labill., the species largely dominant. It is interesting to note that Portugal, one of the European countries that later introduced the eucalypt, is today, worldwide, one of the countries with the highest percentage of its forest area dedicated to this culture. Keywords: eucalypt; botanical gardens; Portugal.

Spectral Response of Eucalyptus saligna under Water Stress in Southern Brazil

The present work aims to assess the effect of water stress on the reflectance emitted by leaves of Eucalyptus saligna individuals. The design was completely randomized and the study comprised 30 subjects who underwent 5 cycles of drought simulation, 45 days each. Five individuals were submitted to water deficit treatment and five were used as controls, remaining in adequate water conditions. The experiment and data collection were performed in the external facilities of the forest management laboratory of the Federal University of Santa Maria, Rio Grande do Sul, Brazil. Which it comprised the period from September 2014 to April 2015. Spectral information was collected from 24-month-old tree individuals in adequate water and water stress situations by means of FieldSpec®3 spectroradiometer. Subsequently, the spectral data for the electromagnetic spectrum range from 400 nm to 1700 nm were processed and analyzed. The resulting spectral behavior varied between water stress cycles. In the 450 nm wavelength range, the reflectances ranged from 3.8% to 7.4%, at 550 nm from 7.9% to 14% and at 650 nm from 4.8% to 8.8%. In the near infrared region, in the 900 nm to 1300 nm range, the reflectances ranged from 28% to 62%. The spectral response of E. saligna showed minimal differences when compared to healthy green vegetation, even though it was exposed to water deficit situations. From the information obtained, this research can be used as a parameter for comparative analysis between species belonging to the genus Eucalyptus sp.

The ongoing dispersion of the Eucalyptus bronze bug (Thaumastocoris peregrinus) in Spain

Aim of stydy: Thaumastocoris peregrinus (Carpinteiro & Dellapé, 2006) is notable for its dispersion potential, and for its damage to a wide range of hosts of the genus Eucalyptus. The intense movement of people and cargo between continents contributes to the success of its geographical distribution on the globe and hinders the adoption of preventive measures. The celerity and precision in the identification of T. peregrinus, as well as its invasion and dispersion routes are fundamental for the implementation of measures to prevent new invasions.Area of Study: Park of Retiro in the community of Madrid, Spain, where T. peregrinus is present.Material and methods: In this paper we analysed this COI mtDNA gene in T. peregrinus, using samples collected in a park in Madrid urban area, to study the possible ways of introduction of this insect in Spain. This goal can be achieved using molecular methods to amplify and sequence the COI mtDNA gene, which is used as a barcode gene.Results: The results confirm that the population found in Madrid belong to T. peregrinus species and that all the specimens are from the same maternal lineage.Research highlights: We present the first molecular information of the population of T. peregrinus present in the country, and suggest and discuss possible routes of introduction of the species in Spain.