Moist Chamber Research Articles

Additions to the Myxomycota of summer rainfall regions of tropical Australia

The myxomycete diversity is poorly known in tropical regions of Australia. We present a list of myxomycetes from the summer rainfall regions of tropical Australia collated from field collections from the wet tropics of Queensland (February 2009) and from the Kimberley region of Western Australia (February 2006, January 2010, May 2011), together with moist chamber cultures of substrates from the Kimberley region collected in October 2004, September 2005, March 2009, July 2009 and January 2010. Sixty six species and two varieties were named, together with a further 12 that could not be identified with confidence. One species, Licea xanthospora , has been recently described from the Kimberley region, and a further seven species ( Ceratiomyxa fruticulosa var. arbuscula , Diderma indicum , Macbrideola argentea , Paradiacheopsis longipes , Physarum echinosporum , Reticularia splendens , and Stemonaria longa ) are new records for Australia. One species ( Physarella oblonga ) recorded from Australia in the 19th century but which had been lost, was recollected.

Spectroscopic Identification and Molecular Modeling of Diethyl 7-hydroxytrideca-2, 5, 8, 11-tetraenedioate: a Herbicidal Compound from Streptomyces sp.

The genus Streptomyces is the wealthiest authority of bioactive compounds with their immense array of chemical substances and activities. With this view, about 10 soil Streptomyces isolates that inhibit more than a weed among Echinochola crusigalli L., Amaranthus spinosus L. and Cyperus rotundus L. under moist chamber and roll towel paper assay were selected from a total of 118 isolates. Based on the percentage of weed growth inhibition and paddy plant shoot growth promoting potency, the isolate DDBH019 was identified as potent, from which a novel herbicidal compound was isolated. Using the physical and chemical properties, the Streptomyces sp. DDBH019-derived herbicidal compound was identified as diethyl 7-hydroxytrideca-2, 5, 8, 11-tetraenedioate. Finally, the molecular dynamics simulation and docking studies validated effective interaction of herbicidal compound with weed receptors. Indeed, the present study portrays a novel lead toward the Streptomyces spp.-derived herbicides against chemical compounds in the agricultural field.

Preservação de córneas: Um breve histórico

The first successful corneal transplantation used tissue from a living donor. The preservation of corneas gained momentum only after Filatov showed that a cadaver´s eye, when stored at low temperature, could be a source of viable corneas for transplants. Three methods proved to be useful for this purpose: moist chamber, cryopreservation, and liquid medium storage. They were introduced in that order. The first provides cold storage of corneas in situ for up to 2 days after death. It is still useful in underdeveloped regions of our planet. Eye banks practically abandoned the second method due to its complexity. Currently, the most popular storage technique is the third. Depending on the composition of the liquid medium, it allows for cold or warm preservation of the cornea ex situ. This article describes the characteristics of the three storage systems in quasi-chronological sequence

DNA barcoding as a tool for identification of plasmodia and sclerotia of myxomycetes (Myxogastria) appearing in moist chamber cultures

DNA barcoding as a tool for identification of plasmodia and sclerotia of myxomycetes (Myxogastria) appearing in moist chamber cultures

New records of coprophilous ascomycetes (Fungi: Ascomycota) from Brazil and Neotropical Region

This study presents the first records from three genera Hypocopra, Pyxidiophora, Zopfiella and the second of the rare species, Cercophora coronata (Cailleux) Udagawa and T. Muroi, for Brazil. It also presents the first record of H. stercoraria (Sowerby) Sacc., P. arvernensis (Breton and Faurel) N. Lundq. and Z. latipes (N. Lundq.) Malloch and Cain for the Neotropical region. Specimens were obtained from dung collected in areas of the Brazilian Savannah cultured in moist chambers. Distribution data, taxonomic descriptions and new substrate records for are presented.

FIRST REPORT OF BOTRYTIS ROT CAUSED BY BOTRYTIS CINEREA ON PEACH IN ECUADOR

Botrytis cinerea is a common plant pathogen that affects stone fruits, including peach ( Prunus persica L.) which is cul- tivated on 6,884 ha with a production of 36,423 ton per year in Ecuador (FAOSTAT, 2016) In September 2015, brown spots were observed on peach fruits var. Diamante in the province of Pichincha, at an altitude of 2348 meters above sea level, 00° 13’ S latitude, and 78° 24’ W longitude. After three days of incubation in a moist chamber at 27 ± 2oC, gray mycelia were associated with the lesions. Aerial myce- lia were plated on PDA and axenic cultures were obtained by hyphal tipping. The isolates had septate hyphae and hya- line branched conidiophores with short clusters of several ovoid conidia formed at the apex. The internal transcribed spacer of isolate UFAH00010 (KX463512) was amplified us- ing primers ITS4-ITS5 (White et al ., 1990) and produced a 547 bp fragment that was sequenced. The BLASTn search showed the sequence had 99% identity with sequence KF859918.1 from B . cinerea CBS 131.28. To test Koch’s postulates, 1 cm 2 plugs taken from the edge of the actively growing B . cinerea isolate UFAH00010 were inoculated on the surface of two healthy peaches and placed in a moist chamber. Non-inoculated peaches were incubated under the same conditions and served as the control. Two days after inoculation, inoculated peaches had beige, circular, sunken lesions that expanded rapidly over the peach surface. Gray cottony-mycelium associated with the lesions was observed under the microscope and identified as B . cinerea . This is the first report of Botrytis rot caused by B . cinerea in peach orchards in Ecuador.

Beltraniopsis rhombispora and Hemibeltrania decorosa from leaf litter in the Atlantic Forest in southern Bahia, Brazil

Abstract Species of the Beltrania group are constantly identified in association with a variety of plant debris in Brazil and different localities of the world. Leaf litter samples of Myrcia splendens and Pera glabrata were collected in the Reserva Biológica de Una, municipality of Una, Bahia state, Brazil, in August 2012, and incubated in moist chambers. Two specimens related to Beltrania group were isolated and identified by morphological criteria. This study aimed to describe and illustrate Beltraniopsis rhombispora for the first time in Brazil. Hemibeltrania decorosa previously reported from Caatinga Biome, Bahia state, has been cited for the first time for Atlantic Forest.

Corticolous myxobiota of the Pernambuco Center of Endemism, Brazil

Situated within the Atlantic Forest domain, the Centro de Endemismo Pernambuco (Pernambuco Center of Endemism) - CEPE is regarded as a priority for biodiversity conservation worldwide. Covering an area of approximately 56,000 km2, it encompasses part of the states of Alagoas, Pernambuco, Paraiba and Rio Grande do Norte in northeastern Brazil. Here we present an identification key to 73 species of Myxomycetes that compose the known corticolous myxobiota of the Dense Ombrofilous Lowland Forest, Semideciduous Lowland Forest, Restinga Forest and Mangrove environments of CEPE. Specimens included here were found developed in natural conditions in the field or obtained through moist chamber culture. Among the species found, Arcyria cinerea, Clastoderma debaryanum, Cribraria confusa, C. violacea and Echinostelium minutum were the most common; and Comatricha longipila, Licea pedicellata, Paradiachaeopsis longipes, Perichaena calongei and Stemonaria fuscoides were the most rare. Our data indicates that the species richness of corticolous myxomycetes in rainforests is lower than that of temperate forests. These same data also suggest that taxonomic diversity (mean number of species per genus) is similar to, or higher than, that found in temperate regions of the world.

Coprophilous Mucorales (ex Zygomycota) from three areas in the semi-arid of Pernambuco, Brazil.

Mucorales comprises fungi commonly isolated as saprobes from soil, dung, stored grains and plants. Although these fungi have been studied in several countries, there are relatively a few reports of them in semi-arid areas. Therefore, the aims of the present study were to assess and compare the Mucorales communities in dung from different species and breeds of herbivores in the semi-arid of Pernambuco, based on the frequency of occurrence and species richness of these fungi. Samples of dung collected in the cities of Arcoverde, Serra Talhada and Sertânia were incubated in moist chambers in triplicate. Altogether, 24 taxa of Mucorales distributed in the genera Absidia, Circinella, Cunninghamella, Lichtheimia, Mucor, Pilobolus, Rhizopus and Syncephalastrum were identified. The highest species richness was found in sheep excrement. Mucor circinelloides f. griseo-cyanus was the most common taxon, followed by M. ramosissimus. The similarity of the composition of Mucorales species was greatest between the excrements of Guzerá and Sindi breeds (bovine). All mucoralean species isolated are being cited for the first time from animal dung found in Caatinga and a new species of Mucor was recorded. An identification key for species of Mucorales from dung in the semi-arid region of Brazil is provided.

First Report of Colletotrichum scovillei Causing Anthracnose Fruit Rot on Pepper in Anhui Province, China

HomePlant DiseaseVol. 100, No. 10First Report of Colletotrichum scovillei Causing Anthracnose Fruit Rot on Pepper in Anhui Province, China PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Colletotrichum scovillei Causing Anthracnose Fruit Rot on Pepper in Anhui Province, ChinaW. Zhao, T. Wang, Q. Q. Chen, Y. K. Chi, T. M. Swe, and R. D. QiW. ZhaoSearch for more papers by this author, T. WangSearch for more papers by this author, Q. Q. ChenSearch for more papers by this author, Y. K. ChiSearch for more papers by this author, T. M. SweSearch for more papers by this author, and R. D. QiSearch for more papers by this authorAffiliationsAuthors and Affiliations W. Zhao T. Wang Q. Q. Chen Y. K. Chi , Institute of Plant Protection and Agro-Products Safety, Anhui Academy of Agricultural Sciences, Hefei, 230031 China T. M. Swe , Biotechnological and Material Science Research Department, Ministry of Science and Technology, Kyaukse 05151, Myanmar R. D. Qi , Institute of Plant Protection and Agro-Products Safety, Anhui Academy of Agricultural Sciences, Hefei, 230031 China, and Scientific Observing and Experimental Station of Crop Pests in Hefei, Ministry of Agriculture, Hefei 230031, China. Published Online:15 Jul 2016https://doi.org/10.1094/PDIS-04-16-0443-PDNAboutSections ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Anthracnose fruit rot is a major disease of pepper (Capsicum annuum), which causes severe damage and enormous economic loss in pepper production. Colletotrichum acutatum, C. coccodes, C. boninense, and C. capsici have been reported as causal agents for anthracnose on pepper in China (Xia et al. 2011; Diao et al. 2013). Since 2014, dark, circular, sunken zones with concentric rings of orange conidial masses, the typical anthracnose symptoms, have appeared on pepper fruits in Shitai, Anhui Province, China. Small tissue pieces from the edges of lesions on fruits were disinfected in 70% (v/v) ethanol for 30 s and in 2% (v/v) hypochlorous acid solution for 2 min, rinsed twice in sterilized water, air-dried, then incubated on potato dextrose agar (PDA) at 25°C. Eight isolates of the pathogen were obtained from different diseased plants. Colony morphology on Spezieller Nährstoffarmer Agar (SNA) was pale gray to pale orange fluffy aerial mycelium. The conidia were hyaline, aseptate, smooth, straight, subcylindrical to clavate, with one end round and one end round or acute, 11.8 to 16.5 µm long and 3.2 to 4.5 µm wide, L/W ratio = 3.6. These morphological characters are consistent with the description of C. scovillei (Damm et al. 2012). To confirm this identification, the internal transcribed spacer (ITS) rDNA regions, glyceraldehyde-3-phosphate dehydrogenase (GADPH) gene, and β-tubulin-2 (TUB2) gene were amplified with the primers ITS1/ITS4, GDF/GDR, and TUBT1/TUBT2, respectively. The consensus sequences of the ITS was deposited in GenBank under the accession number KU680418. Compared with the sequence of strain CBS 126529 of C. scovillei in GenBank (Damm et al. 2012), the amplification products showed 100% homology with the ITS sequence (GenBank Accession No. JQ948267), the GADPH sequence (JQ948597), and the TUB2 sequence (JQ949918), respectively. A pathogenicity test was performed by depositing 10 µl droplets of a suspension (105 conidia/ml) on the surfaces of five artificially wounded fruits (prick a small hole on pepper fruit using needle). Five wounded fruits were inoculated with sterilized distilled water as the control. After 5 days in a moist chamber at 25°C, symptoms similar to those observed on the original pepper plants had developed on the five wounded fruits that had been inoculated, and C. scovillei was reisolated from the lesions. The control fruits remained healthy. Recently, C. acutatum has been considered a species complex. C. scovillei is one of the species that belongs Clade D3 within the C. acutatum species complex (Damm et al. 2012). C. scovillei causing anthracnose disease on pepper was previously reported in Japan and Brazil (Caires et al. 2014; Takeshi et al. 2014). However, to our knowledge, this is the first report of occurrence of anthracnose fruit rot caused by C. scovillei on pepper in China. This disease causes severe damage both in the field and postharvest and there is a need to develop effective control strategies in the pepper production in these regions.

Fungal succession on plant debris in three humid forests enclaves in the Caatinga biome of Brazil

(Fungal succession on plant debris in three humid forests enclaves in the Caatinga biome of Brazil.) Fungal succession (sequential occurrence of sporulating fungi) was investigated on plant debris (leaves, twigs, and barks). The material was collected in three humid forests enclaves in the Caatinga biome, northeast of Brazil, and the samples were incubated in moist chambers to verify the occurrence of conidial fungi in four incubations periods: 1 (up to 10 days of incubation), 2 (11–20 days), 3 (21–30), and 4 (31–40 days). A total of 213 taxa were recorded. The species richness was similar in the three enclaves studied. Only two species occurred in all periods and more than one substrate: Chloridium virescens ((Pers.) W. Gams & Hol.-Jech) occurred in the leaves and barks and Ellisembia adscendens ((Berk.) Subram.) occurred in the barks and twigs. Nonmetric multidimensional scaling (NMDS) indicates that substrate was the most determinant factor for the fungal community composition compared with area and incubation periods. The result of analysis of similarity demonstrates that the groups formed in NMDS were significant. The succession on decaying leaves demonstrated the highest richness among the substrates studied. In the leaves, the major richness values were detected in the P1 period, while in the barks and twigs, the major richness values were detected in the P1 and P2 periods. Species richness decreases after 20 incubation days in all substrates. Cluster analysis indicates the formation of communities relating to incubation periods in the leaves. The results of this study demonstrated a fungal succession on plant debris during the incubation period.

Taxonomy and developmental morphology of Rogersiomyces malaysianus comb. nov. (Cantharellales, Agaricomycetes)

A basidiomycete fungus from Vietnam, grown in a moist chamber on bark (as substrate) was identified as Hyphobasidiofera malaysiana. The isolation of this fungus into axenic culture allowed for investigations such as culture morphology, large and small subunit molecular phylogenies, life cycle karyology, and mating experiments. Comparative morphological data revealed that this species belongs to Rogersiomyces and the name Rogersiomyces malaysianus comb. nov. is proposed. Molecular studies revealed close relationships of Rogersiomyces, Sistotrema sensu lato, and Hydnum sensu stricto (Cantharellales, Agaricomycetes). The fungus produces binucleate basidiospores that germinate to form clamped and dikaryotic mycelium. The cultural characters and reproductive structures of this unusual sistotremoid fungus are described. It was concluded that the characteristic of dikaryotization into basidium, ephemeral basidiomata, and statismosporic basidia represent an adaptation of this fungus to irregular, but plentiful moistening during monsoon climate.

Myxomycetes in Brazilian mangroves: species associated with Avicennia nitida, Laguncularia racemosa and Rhizophora mangle

Mangroves are distributed among tropical and subtropical coastlines of all oceans, and associated macroflora and macrofauna are generally well studied. However, information on mangrove-associated microbiota is still scarce. To help fill this gap in knowledge, we conducted research on the occurrence of Myxomycetes in the southern coast of Pernambuco state, northeastern Brazil. In the Rio Formoso estuary, we examined adult Rhizophora mangle (Rm), Laguncularia racemosa (Lr) and Avicennia nitida (An), collecting samples of live trunk bark (Bk), twigs from aerial litter (Tg), and aerial leaf litter (Lf) for moist chamber culture (n = 600). The following species were identified: Arcyria cinerea (Rm/Tg); A. pomiformis (Rm;Lr/Bk); Collaria arcyrionema (Rm/B); Clastoderma debaryanum (Lr/Bk; Rm/Tg); Cribraria violacea (Rm/Bk;Tg); Physarum auriscalpium (Rm/Tg); P. tenerum (Rm/Bk); Stemonitis fusca (Lr/Tg); S. herbatica (Rm/Lf); S. virginiensis (Rm/Tg) and Stemonaria irregularis (An/Lf). The percentage of positive cultures was very low (24 %), with Rm as the predominant substrate with eight species and Tg as the predominant microhabitat. The majority of species are rare (60 %) and Physarum auriscalpium was the only species frequently registered. The taxonomic diversity indices ranged from 1.00 (Lf;Bk) to 1.20 (Tg). There was no similarity in the composition of myxobiota found on the substrates and microhabitats analyzed. Only S. irregularis was found in mangroves that inhabit areas of higher salinity. Physarum tenerum is reported here for the first time in the mangrove environment.

First Report of Canker and Root Rot of Almond Caused by Phytophthora plurivora in Turkey

HomePlant DiseaseVol. 100, No. 7First Report of Canker and Root Rot of Almond Caused by Phytophthora plurivora in Turkey PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Canker and Root Rot of Almond Caused by Phytophthora plurivora in TurkeyO. Çiftçi, Ş. Türkölmez, S. Derviş, and Ç. U. SerçeO. ÇiftçiSearch for more papers by this author, Ş. TürkölmezSearch for more papers by this author, S. DervişSearch for more papers by this author, and Ç. U. SerçeSearch for more papers by this authorAffiliationsAuthors and Affiliations O. Çiftçi Ş. Türkölmez , Diyarbakır Plant Protection Research Station, 21110 Yenişehir, Diyarbakır, Turkey S. Derviş , Department of Plant Protection, Agriculture Faculty, Mustafa Kemal University, 31034 Antakya, Hatay, Turkey Ç. U. Serçe , Department of Plant Production and Technologies, Faculty of Agricultural Sciences and Technologies, Niğde University, 51240 Niğde, Turkey. Published Online:5 May 2016https://doi.org/10.1094/PDIS-12-15-1533-PDNAboutSections ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Almond [Prunus dulcis (Miller) D.A. Webb.] is one of the most frequently consumed nut species grown in Turkey. In early March 2015, ∼20% of 13,000 one-year-old almond (P. dulcis cv. Ferragnes) seedlings in a nursery in Gaziantep showed sunken and blackened cankers on aboveground parts and root rot. Tissue samples taken from the margins of stem cankers and root lesions were placed on grated apple corn meal agar (Türkölmez et al. 2015) amended with P5ARPH per liter. Plates were incubated for 4 days at 20°C in the dark and a Phytophthora species was consistently isolated from the tissues. Isolates were homothallic with paragynous antheridia, smooth-walled spherical oogonia (24.7 to 29.6-μm diam), and both plerotic (1.3 to 1.4-μm wall diam) and aplerotic golden brown oospores (23.3 to 27.8 μm diam) on V8 juice agar (V8A) and produced semipapillate, noncaducous sporangia (35.5 to 53.2 × 26.3 to 38.4 μm; L:B ratio from 1.3 to 1.4 μm), which were usually obpyriform, ovoid, ellipsoid or irregular, and rarely possessed more than one apex, formed on simple or sympodial sporangiophores in nonsterile soil extracts. On V8 agar, colonies had a slight chrysanthemum growth pattern with limited aerial mycelium at the center of the colonies, whereas on PDA the colonies had a clear chrysanthemum growth pattern and aerial mycelia at the center of the colony. The minimum, optimum, and maximum temperatures for mycelium growth on V8A were 5, 25, and 32°C, respectively. On the basis of the morpho-physiological features, isolates were identified as P. plurivora T. Jung & T.I. Burgess from the ‘P. citricola complex’ (Jung and Burgess 2009). Genomic DNA was extracted from two representative isolates. The internal transcribed spacer (ITS) region of rDNA was amplified using the ITS6/ITS4 primer pair and sequenced (GenBank Accession Nos. KU221328 and KU310937). BLAST searches showed a 100% identity with a type isolate of P. plurivora (FJ665225). The sequence also contained the polymorphic nucleotides that are distinctive of this species (Jung and Burgess 2009). Pathogenicity was tested on shoot segments from ten 1- to 2-year-old P. dulcis cv. Ferragnes (5 to 7 mm diam, 20 cm length) by replacing the 5-mm bark disks of shoots in the middle of each shoot segment with the same-sized mycelial disks of P. plurivora grown on V8 agar. Ten control segments were similarly inoculated with sterile V8 agar disks. The wounds were wrapped with Parafilm, and the shoots were incubated in moist chambers in 100% RH at 23°C. Phytophthora plurivora caused cankers on almond shoots within 5 days after inoculation, and the noninoculated control shoots remained symptomless. To test the pathogenicity on roots, primary roots of 10 P. dulcis cv. Ferragnes seedlings (1-year-old) were wounded with a scalpel, and mycelial disks (3 per plant) of P. plurivora grown on V8 agar were placed under the cortical tissue after removing 10 to 15 cm of soil around the root base. The inoculated and exposed roots were then covered with soil. Ten control seedlings were similarly inoculated with sterile disks. The soil was kept wet by watering plants daily as required. All seedlings were grown in a greenhouse at air temperatures from 24 to 30°C. No disease developed in the controls, but P. plurivora caused wilt and root rot after 2 months. Koch’s postulates were satisfied after reisolating P. plurivora from all inoculated shoots and roots. To our knowledge, this is the first report of P. plurivora causing canker and root rot on almond plants. In late April 2015, all naturally infected almond seedlings in the nursery were collapsed and destroyed by this oomycete, indicating that it might be a significant threat to almond plantations and orchards in the postnursery phase.

Components of resistance of conilon coffee that reduce the rate of leaf rust development

This study aimed to quantify the levels of resistance of 39 hybrids “Clone 83 × Clone 02”of Coffea canephora var. conilon to the races II (v5) and XXXIII (v5,7,9) of H. vastatrix. To study the resistance of the genotypes, leaf discs were removed from the plants and spreaded on the top of a stainless steel screen inside gerbox as a moist chamber. The gerboxes were mantained at 22 ± 2 °C in the dark for 48 h and under 12 h of photoperiod, respectively. The hybrids were classified into four levels: resistant (R), moderately resistant (MR), moderately susceptible (MS) and susceptible (S). Leaf discs (%) containing sporulated lesions was the resistance component that had the greatest absolute correlation (0.95). The level of resistance of the hybrids varyied according to the race of the pathogen. The percentage of R, MR, MS and S of the hybrids to race II and XXXIII were 25 %, 25 %, 38 %, and 11 %, and 13 %, 37 %, 42 %, and 8 %, respectively. Nine (25 %) and five (13 %) hybrids were R to race II and XXXIII, respectively. Four hybrids (21, 30, 48 and 66) showed vertical resistance to races II and XXXIII. Possibly these hybrids have the resistance factor SH6, because they were resistant to race XXXIII v5,7,9. Leaf discs (%) with sporulating lesions can be used as a reference in future studyies of screening genotypes with horizontal resistance to C. canephora genotypes to leaf rust.

Comportamento mecânico de material fresado após processo de estabilização granulométrica e química por meio da incorporação de cimento e cinza de casca de arroz moída

RESUMO Este trabalho objetivou avaliar, através de ensaios laboratoriais, a viabilidade da utilização de material fresado puro e estabilizado (mecânica, granulométrica e quimicamente) em camadas de pavimentos flexíveis. Os materiais fresados são oriundos da BR-290 e da ERS-509 no estado do Rio Grande do Sul. Foi realizada estabilização granulométrica, sendo determinado o teor de 70% de material fresado e 30% de agregado natural, sendo bastante efetiva na elevação do ISC (de 56 para 95% e de 21 para 68%, para o fresado da BR-290 e ERS-509). Para os ensaios compressão simples foram moldados corpos-de-prova cilíndricos de 10x20 cm com diferentes teores de cimento Portland (CP-IV 32), sendo determinados os teores de 4,86% (BR-290) e 5,37% (ERS-569) a partir da resistência à compressão de 2,1 MPa aos 28 dias. A partir dos resultados obtidos, em uma segunda etapa da pesquisa utilizando somente o material fresado da ERS-509, foram moldados corpos de prova para determinação da resistência à compressão, da resistência à tração e do módulo de resiliência; sendo nestes substituído, em massa, o CP-IV em 15, 30 e 50% por cinza de casca de arroz moída (#325 e #500), colocados em câmara úmida por 7, 28 e 160 dias. A análise dos resultados mostrou que para compressão simples e à tração, a substituição de 15% de cimento por CCA se mostrou eficiente, não havendo queda de resistência comparado as amostras de referência. Também fica evidente a eficácia da CCA, apresentando resultados positivos sempre que comparados àquelas misturas somente com o real teor de cimento Portland utilizado, juntamente com o apelo ambiental se torna uma alternativa interessante de utilização em camadas de pavimentos.

Does elevation influence the distributional patterns of tropical myxomycetes? A case study in Costa Rica

ABSTRACTIn order to test the hypothesis that elevation may be an important factor accounting for the distribution of myxomycetes in tropical forests, this project was designed and conducted in Costa Rica. Two lower elevational belts were selected for this work due to their floristic and structural resemblance. Using the moist chamber technique, 40 different sites located in four different transects in two different macroclimatic regions were surveyed using three substrates during the rainy and the dry periods of 2014 and 2015. The results showed a lack of differences in diversity-based estimators according to elevation using different approaches and taxonomic differences were found across transects, collecting periods and substrates but not in relation with elevation either. Our results suggest that when increased spatial sampling resolution is implemented and floristic elements are common, elevation may not be as important of a factor in shaping the distribution of myxomycetes in tropical forests as commonly believed.

Cobalt oxide nanoparticles aggravate DNA damage and cell death in eggplant via mitochondrial swelling and NO signaling pathway.

BackgroundDespite manifold benefits of nanoparticles (NPs), less information on the risks of NPs to human health and environment has been studied. Cobalt oxide nanoparticles (Co3O4-NPs) have been reported to cause toxicity in several organisms. In this study, we have investigated the role of Co3O4-NPs in inducing phytotoxicity, cellular DNA damage and apoptosis in eggplant (Solanum melongena L. cv. Violetta lunga 2). To the best of our knowledge, this is the first report on Co3O4-NPs showing phytotoxicity in eggplant.ResultsThe data revealed that eggplant seeds treated with Co3O4-NPs for 2 h at a concentration of 1.0 mg/ml retarded root length by 81.5 % upon 7 days incubation in a moist chamber. Ultrastructural analysis by transmission electron microscopy (TEM) demonstrated the uptake and translocation of Co3O4-NPs into the cytoplasm. Intracellular presence of Co3O4-NPs triggered subcellular changes such as degeneration of mitochondrial cristae, abundance of peroxisomes and excessive vacuolization. Flow cytometric analysis of Co3O4-NPs (1.0 mg/ml) treated root protoplasts revealed 157, 282 and 178 % increase in reactive oxygen species (ROS), membrane potential (ΔΨm) and nitric oxide (NO), respectively. Besides, the esterase activity in treated protoplasts was also found compromised. About 2.4-fold greater level of DNA damage, as compared to untreated control was observed in Comet assay, and 73.2 % of Co3O4-NPs treated cells appeared apoptotic in flow cytometry based cell cycle analysis.ConclusionThis study demonstrate the phytotoxic potential of Co3O4-NPs in terms of reduction in seed germination, root growth, greater level of DNA and mitochondrial damage, oxidative stress and cell death in eggplant. The data generated from this study will provide a strong background to draw attention on Co3O4-NPs environmental hazards to vegetable crops.

Data on the occurrence of corticolous myxomycetes from Denali National Park, Alaska.

This data set contains data about corticolous (bark-inhabiting) myxomycetes from a 100×100 m2 plot including ca. 380 trees of Picea glauca (white spruce), of which 260 were large enough that bark could been sampled to prepare moist chamber cultures. At the end of the data set records of myxomycetes from 66 moist chambers prepared with bark of deciduous trees and shrubs, and outermost twiglets of P. glauca are included. These were sampled around the plot for purposes of comparison. A second data set shows measured tree parameters for the 380 trees examined in the plot. Data were used for a statistical analysis to search for environmental factors decisive for the occurrence of corticolous myxomycetes (Schnittler et al., 2016) [1].

Ecological factors limiting occurrence of corticolous myxomycetes – a case study from Alaska

Abstract In search of decisive factors for the occurrence of corticolous myxomycetes we investigated a plot comprising 380 white spruce trees (Picea glauca) in the Denali National Park and Reserve, Alaska. Moist chambers were prepared from the bark of 260 trees and cultured for 77 d. Occurrence patterns of corticolous myxomycetes were related to tree position and eight environmental variables; among them are diameter at breast height (dbh), tree age and vitality, and bark pH. Tree age and dbh, but not vitality, are highly correlated with each other. Bark pH decreases with increasing diameter of a tree. Only two species of myxomycetes, Leocarpus fragilis (164 records) and Paradiacheopsis solitaria (72) were common. The first species fruits typically on litter; in the study it preferred small trees (low dbh) with a rather high bark pH and high vitality. The second species is known as truly corticolous and prefers thick (usually older) trees with a low pH and a lower vitality. The low and statistically insignificant Cole index for association between the two species (0.047) points to niche separation. For both species mark connection functions indicate a near-random spatial distribution among trees. L. fragilis could effectively colonize small trees (55% of all records occurred on trees below 15 cm dbh). P. solitaria seems to avoid small trees (92% of all records occurred on trees exceeding 15 cm dbh). Our data indicate that the occurrence of corticolous myxomycetes is not limited by dispersal capability but by habitat suitability.