On the enigmatic scent glands of dyspnoan harvestmen (Arachnida, Opiliones): first evidence for the production of volatile secretions

La utilización en encuestas de preguntas con tarjetas de respuesta está totalmente aceptada por la comunidad investigadora. Esto supone una carga de trabajo “extra” en la tarea del entrevistador, lo que explica que en ocasiones no se utilicen correctamente. Pese a esta situación, hay muy poca literatura sobre la influencia de las tarjetas en las respuestas del entrevistado. El objetivo de este trabajo es profundizar en los efectos que la utilización de tarjetas tiene en la calidad de las respuestas del cuestionario, partiendo de la hipótesis que considera que las tarjetas —pese a complicar la tarea del encuestador— suponen importantes mejoras en la administración del cuestionario. Utilizaremos para ello un estudio del Centro de Investigaciones Sociológicas con 23 preguntas de tarjeta, comparando las respuestas de los entrevistados que utilizaron las tarjetas con aquellos que no las emplearon.Using “response cards” in question surveys is unanimously approved by the research community. The fact that this represents an extra workload for the interviewer’s task explains why they sometimes are not used correctly. Despite this situation there is a paucity of literature on the influence of the response card on the respondent’s answers. The aim of this study is to deepen the analysis of how using these cards affect the quality of the survey’s responses. To do so, we start from the assumption that the cards —while complicating the interviewer’s task, result in significant improvements in the survey’s administration. For this purpose we will use a study with 23 card questions (question cards) by the Centro de Investigaciones Sociológicas, (the Spanish Centre for Sociological Research), and we will compare the answers of respondents that used cards with those who did not

SEM observations on the seed surface of Hyacinthaceae

Data on seed morphology of 132 species from 40 genera of all subfamilies (Ornithogaloideae, Hyacinthoideae, Urgineoideae, Oziroëoideae) of Hyacinthaceae are presented. So far, this is the most extensive study on the seed surface of Hyacinthaceae using scanning electron microscopy (SEM), and we also give insights into the systematic implications of seed surface micromorphology

Chrysomelidial in the Opisthonotal Glands of the Oribatid Mite, Oribotritia berlesei

Gas chromatographic–mass spectrometric analyses of whole body extracts of Oribotritia berlesei, a large-sized soil-dwelling oribatid mite, revealed a consistent chemical pattern of ten components, probably originating from the well-developed opisthonotal glands. The three major components of the extract were the iridoid monoterpene, (3S,8S)-chrysomelidial (about 45% of the extract), the unsaturated hydrocarbon 6,9-heptadecadiene, and the diterpene β-springene (the latter two, each about 20–25% of the extract). The remaining minor components (together about 10% of the extract) included a series of hydrocarbons (tridecene, tridecane, pentadecene, pentadecane, 8-heptadecene, and heptadecane) and the tentatively identified 9,17-octadecadienal. In contrast, analysis of juveniles showed only two compounds, namely a 2:1 mixture of (3S,8S)-chrysomelidial and its epimer, epi-chrysomelidial (3S,8R-chrysomelidial). Unexpectedly, neither adult nor juvenile secretions contained the so-called astigmatid compounds, which are considered characteristic of secretions of oribatids above moderately derived Mixonomata. The chrysomelidials, as well as β-springene and octadecadienal, are newly identified compounds in the opisthonotal glands of oribatid mites and have chemotaxonomic potential for this group. This is the first instance of finding chrysomelidials outside the Coleoptera

Riccia atromarginata (Ricciaceae, Marchantiophyta) new to the Western Balkans, with notes on its morphology

This is the first record of the liverwort Riccia atromarginata for the Western Balkans. It was found on conglomerate terraces in the city of Podgorica, Montenegro, at the confluence of the rivers Ribnica and Morača. The material from Montenegro as well as living samples from Tenerife, Gran Canaria and Cyprus served as a basis for a detailed description of the main characteristics of the species, on the basis of which Riccia atromarginata can be reliably identified. However, for some characteristics there is a clear variability

Riccia atromarginata (Ricciaceae, Marchantiophyta) new to the west Balkan peninsula

This is the first record of the liverwort Riccia atromarginata on the west Balkan Peninsula. It was found on conglomerate terraces in Podgorica, Montenegro, at the confluence of Ribnica and Moraca River. The material from Montenegro as well as living samples from Tenerife, Gran Canaria and Cyprus serve as a basis of a detailed description of the species on which to Riccia atromarginata can be reliably identified. However, there is a distinct variability of some characteristics

Barrelier’s Speedwell (<i>Veronica barrelieri</i> Schott ex Roem. et Schult., Plantaginaceae)—Potential of Free Volatile Compounds for Horticulture

Barrelier’s Speedwell or Veronica barrelieri Schott ex Roem. et Schult. (syn. Pseudolysimachion barrelieri (Schott ex Roem. et Schult.) Holub (family Plantaginaceae) grows on dry grasslands and rocky slopes in southeastern Europe. Because of its attractive blue flowers arranged in dense inflorescences up to 30 cm long, this plant has great potential for horticulture, especially in dry climates. As part of studies on biologically active compounds in this species, free VCs (Volatile Compounds) were analyzed by GC-MS (Gas Chromatography with Mass Spectrometry) and micromorphological features were studied by SEM (Scanning Electron Microscopy). Free VCs from aboveground plant parts collected during flowering were characterized by a considerably high content of oxygenated diterpene phytol, followed by hexadecanoic acids, pentacosane, and caryophyllene oxide. These compounds are most abundant in the composition of VCs isolates of V. barrelieri from all five Croatian localities studied. Non-glandular and two subtypes of capitate glandular trichomes were detected on the stems, leaves and calyx of V. barrelieri. Veronica barrelieri attracts pollinators with its attractive flower appearance and specialized metabolites such as free VCs, which are environmentally friendly and possible natural botanical pesticides

Barrelier&rsquo;s Speedwell (Veronica barrelieri Schott ex Roem. et Schult., Plantaginaceae)&mdash;Potential of Free Volatile Compounds for Horticulture

Barrelier&rsquo;s Speedwell or Veronica barrelieri Schott ex Roem. et Schult. (syn. Pseudolysimachion barrelieri (Schott ex Roem. et Schult.) Holub (family Plantaginaceae) grows on dry grasslands and rocky slopes in southeastern Europe. Because of its attractive blue flowers arranged in dense inflorescences up to 30 cm long, this plant has great potential for horticulture, especially in dry climates. As part of studies on biologically active compounds in this species, free VCs (Volatile Compounds) were analyzed by GC-MS (Gas Chromatography with Mass Spectrometry) and micromorphological features were studied by SEM (Scanning Electron Microscopy). Free VCs from aboveground plant parts collected during flowering were characterized by a considerably high content of oxygenated diterpene phytol, followed by hexadecanoic acids, pentacosane, and caryophyllene oxide. These compounds are most abundant in the composition of VCs isolates of V. barrelieri from all five Croatian localities studied. Non-glandular and two subtypes of capitate glandular trichomes were detected on the stems, leaves and calyx of V. barrelieri. Veronica barrelieri attracts pollinators with its attractive flower appearance and specialized metabolites such as free VCs, which are environmentally friendly and possible natural botanical pesticides

Salicylic Acid Enhances Growth, Photosynthetic Performance and Antioxidant Defense Activity Under Salt Stress in Two Mungbean [Vigna radiata (L.) R. Wilczek] Variety

Salt is regarded as a main cause for reduced yield under challenging conditions. Mungbean, a valuable protein crop, is sensitive to salt stress, leading to yield shortage. The growth hormone, salicylic acid (SA), enhances several processes necessary to confer salt tolerance and relieves poor agricultural yield. Seeds of mungbean were initially pretreated with SA (0.5 mM) for 4 h before sowing, while under a cumulative combination of SA + salt regimes: control, SA, 100 mM, SA +100 mM, 200 mM and SA +200 mM. Our study examined photosynthesis parameters such as photosynthetic pigment concentration, chlorophyll a fluorescence, protein, proline, and antioxidant enzymes in plants subjected to single and combined SA + salt stress concentrations. The result showed a greater decline in SPAD and photosynthetic quantum yield under 200 mM NaCl at 43% in Var. 145 than in Var. 155 at 32% compared to 11% in SA +100 mM and 34% in SA + 200 mM treatments in both varieties. Var. 145 was found to be more sensitive to 100 and 200 mM NaCl salt stress. In Var. 155, chlorophyll a and chlorophyll b concentrations were higher under control 52%, SA + 100 mM 49%, and SA +200 mM 42% than in Var. 145 at 51%, 38%, and 31%. Protein and proline revealed a higher content in Var. 155 in contrast to the lower activity in Var. 145. The enhanced performance of the Var. 155 exposed to SA + salt stress was followed by an increase in the activities of peroxidase (POD), CAT while the activity of MDA revealed a significant increase in Var. 145 under 100 mM 43% and 200 mM 48% NaCl treatment compared to Var. 155, which had 38% and 34%. The above results suggest that SA-treated Var. 155 confers tolerance to salt stress and is accompanied with a high osmoprotectant responses as provided by SA in Var. 155 than Var. 145. The potency of SA in providing salt tolerance capacity to plants is a future research interest to maintain sustainable yield in mungbean seedlings

Differential effects of carbohydrates on arabidopsis pollen germination

Pollen germination as a crucial process in plant development strongly depends on the accessibility of carbon as energy source. Carbohydrates, however, function not only as a primary energy source, but also as important signaling components. In a comprehensive study, we analyzed various aspects of the impact of 32 different sugars on in vitro germination of Arabidopsis pollen comprising about 150 variations of individual sugars and combinations. Twenty-six structurally different mono-, di- and oligosaccharides, and sugar analogs were initially tested for their ability to support pollen germination. Whereas several di- and oligosaccharides supported pollen germination, hexoses such as glucose, fructose and mannose did not support and even considerably inhibited pollen germination when added to germination-supporting medium. Complementary experiments using glucose analogs with varying functional features, the hexokinase inhibitor mannoheptulose and the glucose-insensitive hexokinase-deficient Arabidopsis mutant gin2-1 suggested that mannose- and glucose-mediated inhibition of sucrose-supported pollen germination depends partially on hexokinase signaling. The results suggest that, in addition to their role as energy source, sugars act as signaling molecules differentially regulating the complex process of pollen germination depending on their structural properties. Thus, a sugar-dependent multilayer regulation of Arabidopsis pollen germination is supported, which makes this approach a valuable experimental system for future studies addressing sugar sensing and signaling.This study was supported by the Bayerisches Staatsministerium für Umwelt, Gesundheit und Verbraucherschutz, the SFB 56 and the DFG Graduiertenkolleg 1342 [to T.R.]; MINECO [contract No. CTQ2015-64425-C2-1-R to J.M.G.F]; the Junta de Andalucía [contract No. FQM2012-1467 to J.M.G.F]; the European Regional Development Funds (FEDER) [to J.M.G.F.]; the Ministry of Education, Youth and Sports of CR within the National Sustainability Program I (NPU I) [grant No. LO1415 to T.R.]; and by the Danish Council for Independent Research, Danish Ministry of Higher Education and Science to [Individual Postdoctoral Grant No. 4093-00255 to D.K.G.].Peer reviewe