Isoflavone levels in five soybean (Glycine max) genotypes are altered by phytochrome-mediated light treatments

The objective of the present study was to determine whether concentrations of different isoflavones (puerarin, genistein, genistin, daidzein, and daidzin) in shoots and roots of five selected soybean genotypes would respond the same or differently to red (650 nm peak transmittance) and far-red (750 nm peak transmittance) light treatments given under controlled environments. Levels of isoflavones (mg g(-1) dry weight biomass) present in seeds, control roots, and shoots and 10 day light-treated seedlings (light, dark, red, and far-red wavelengths) of soybean (Glycine max) were determined by high-performance liquid chromatography analysis in comparison with known isoflavone standards. Seeds of the five soybean genotypes studied consistently stored most of their isoflavones as glucosyl conjugates (e.g., daidzin, genistin, and puerarin). For the five soybean genotypes, isoflavone levels were lower in the seeds as compared with roots plus shoots of control, time zero (first true leaf stage) seedlings. Following 10 days of the respective light treatments, we found that (i) isoflavone levels were enhanced in dark-grown plants over light-grown plants for three of the five genotypes (a new finding) and the reverse occurred for a single genotype (a typical response of legumes) and (ii) generally, far-red end of day (EOD) light treatment enhanced total isoflavone levels in roots plus shoots over red EOD light treatment. Results from the present study show that phytochrome does appear to play a role in regulating isoflavone levels in developing soybean seedlings and that this influence by red/far-red-mediated phytochrome reactions is strongly dependent on the genotypes selected for study.     

The occurrence of the avian schistosome Allobilharzia visceralis Kolákrová, Rudolfová, Hampl et Skirnisson, 2006 (Schistosomatidae) in the tundra swan, Cygnus columbianus (Anatidae), from North America

Twelve tundra swans, Cygnus columbianus (Ord), from Nevada and one from New Mexico were collected and examined for schistosomes. Mature worms, determined as Allobilharzia visceralis, were found in 92% of the swans, in the inferior mesenteric vein of the large intestine and its branches. In 12 cases, there was endophlebitis of the inferior mesenteric vein. The morphology of the worms is consistent with the recently described genus Allobilharzia. Placement in this genus was confirmed also by phylogenetic analysis of nuclear 28S, 18S and, internal transcribed spacer (ITS) ribosomal DNA (rDNA), and mitochondrial cytochrome oxidase I (CO1) sequences. Data further suggest the worms are con-specific with the European A. visceralis, the only described species of the genus and which was found to be the sister taxon to the most diverse avian schistosome genus, Trichobilharzia. This is the first report of a schistosome infection from native swans in North America.     

Accurate Dereplication of Bioactive Secondary Metabolites from Marine-Derived Fungi by UHPLC-DAD-QTOFMS and a MS/HRMS Library

In drug discovery, reliable and fast dereplication of known compounds is essential for identification of novel bioactive compounds. Here, we show an integrated approach using ultra-high performance liquid chromatography-diode array detection-quadrupole time of flight mass spectrometry (UHPLC-DAD-QTOFMS) providing both accurate mass full-scan mass spectrometry (MS) and tandem high resolution MS (MS/HRMS) data. The methodology was demonstrated on compounds from bioactive marine-derived strains of Aspergillus, Penicillium, and Emericellopsis, including small polyketides, non-ribosomal peptides, terpenes, and meroterpenoids. The MS/HRMS data were then searched against an in-house MS/HRMS library of ~1300 compounds for unambiguous identification. The full scan MS data was used for dereplication of compounds not in the MS/HRMS library, combined with ultraviolet/visual (UV/Vis) and MS/HRMS data for faster exclusion of database search results. This led to the identification of four novel isomers of the known anticancer compound, asperphenamate. Except for very low intensity peaks, no false negatives were found using the MS/HRMS approach, which proved to be robust against poor data quality caused by system overload or loss of lock-mass. Only for small polyketides, like patulin, were both retention time and UV/Vis spectra necessary for unambiguous identification. For the ophiobolin family with many structurally similar analogues partly co-eluting, the peaks could be assigned correctly by combining MS/HRMS data and m/z of the [M + Na]⁺ ions.     

Efficacy of five selected acaricides against Tetranychus urticae (Acari: Tetranychidae) and their side effects on relevant natural enemies occurring in citrus orchards

BACKGROUND: Three groups of natural enemies are fundamental in citrus IPM in Spain: coccinellid and phytoseiid predators and hymenopteran parasitoids. Tetranychus urticae Koch is an important pest affecting citrus, for which biological control has not yet been achieved; therefore, acaricides are commonly used to control it. The goal of this study was to measure the efficacy of different acaricides on this mite and their side effects on three natural enemies relevant for citrus (Cryptolaemus montrouzieri Mulsant, Neoseiulus californicus McGregor and Aphidius colemani Viereck).RESULTS: Some products proved highly effective against T. urticae and harmless to A. colemani (mineral oil, tebufenpyrad, clofentezine and fenazaquin). However, almost all products tested were slightly harmful for both the predators considered. Fenazaquin was even moderately harmful for N. californicus. CONCLUSION: Further studies, like that presented here, are necessary to gain a better understanding of integrating biological and chemical controls. When considering both efficacy and side effects on beneficial arthropods, the best options would seem to be mineral oil, tebufenpyrad and clofentezine. However, it is urgent to complete testing of the side effects of the acaricides used in citrus. This question is crucial if the fact that two recently introduced Tetranychidae are being controlled in citrus by chemical means exclusively is considered.     

Multivariate analysis of toxicological and environmental properties of soil nematicides

BACKGROUND: In intensive agriculture, the use of pesticides and soil fumigants is necessary to produce economically viable crops worldwide. However, this practice may involve undesirable effects on human health and the environment. In 1995, methyl bromide was restricted by the Montreal Protocol because of possible ozone depletion. The objective of this study was to compare intrinsic environmental and toxicological properties of 11 active substances with nematicidal properties, some of them recognized as methyl bromide alternatives. RESULTS: Four groups of active substances were discriminated by a series of principal component analyses (PCAs): (a) high toxicity to non-target fauna, humans and animals and medium persistence in the environment (cadusafos, ethoprophos and fenamiphos); (b) high toxicity to humans, animals and non-target fauna and high persistence (carbofuran and fosthiazate); (c) low toxicity to non-target fauna, humans and animals and low persistence (carbosulfan, benfuracarb and oxamyl); (d) low toxicity to humans, animals and non-target fauna and medium persistence in the environment (1,3-dichloropropene, chloropicrin and methyl bromide). CONCLUSION: Evaluating the multiple aspects of toxicological and environmental properties of active substances through PCA is proposed as a helpful tool for initially comparing the complex toxicological behaviour of active substances as plant protection products.     

High stability of nuclear microsatellite loci during the early stages of somatic embryogenesis in Norway spruce

Somatic embryos of Norway spruce (Picea abies (L.) Karst.) differentiate from proembryogenic masses (PEMs), which are subject to autodestruction through programmed cell death. In PEMs, somatic embryo formation and activation of programmed cell death are interrelated processes. We sought to determine if activation of programmed cell death in PEMs is caused by genetic aberrations during somatic embryogenesis. Based on the finding that withdrawal of auxin and cytokinin induces programmed cell death in PEMs, 1-week-old cell suspensions were cultured in medium either with or without auxin and cytokinin and then transferred to maturation medium containing abscisic acid. We analyzed the stability of three nuclear simple sequence repeat (SSR) microsatellite markers at successive stages of somatic embryogenesis in two cell lines. There were no mutations at the SSR loci at any of the successive developmental stages from PEMs to cotyledonary embryos, irrespective of whether or not the proliferation medium in which cell suspensions had been cultured contained auxin or cytokinin. The morphologies of plants regenerated from the cultures were similar, although withdrawal of auxin and cytokinin significantly stimulated the yield of both embryos and plants. We conclude, therefore, that the high genetic stability of somatic embryos in Norway spruce is unaffected by the induction of programmed cell death caused by withdrawal of auxin and cytokinin.     

Relationship of wood composition to growth traits of selected open-pollinated families of <Emphasis Type="Italic">Eucalyptus urophylla</Emphasis> from a progeny trial in Vietnam

Lignin and cellulose contents and wood basic density were related to diameter at breast height (DBH) in six fast-growing and five slow-growing families from a combined progeny test and seedling seed orchard of Eucalyptus urophylla grown for 10 years in northern Vietnam. The mean cellulose content of the fast-growing families was significantly higher than that of the slow growing-families (40.0 and 37.1%, respectively), and for individual trees cellulose content was significantly correlated phenotypically with DBH. Wood basic density was significantly lower in the fast-growing group than in the slow-growing group (0.506 and 0.535 g cm⁻³, respectively), and was significantly negatively correlated phenotypically with DBH. The lignin contents were not significantly different between groups. Cellulose content and wood basic density were not correlated. The main conclusion is that there is no obstacle to combining high growth rate with high cellulose content, for plantation of forests intended mainly for pulpwood.     

Resistance to amitraz in the parasitic honey bee mite Varroa destructor is associated with mutations in the β-adrenergic-like octopamine receptor

Varroa destructor is considered a major reason for high loss rate of Western honey bee (Apis mellifera) colonies. To prevent colony losses caused by V. destructor, it is necessary to actively manage the mite population. Beekeepers, particularly commercial beekeepers, have few alternative treatments other than synthetic acaricides to control the parasite, resulting in intensive treatment regimens that led to the evolution of resistance in mite populations. To investigate the mechanism of the resistance to amitraz detected in V. destructor mites from French and U.S. apiaries, we identified and characterized octopamine and tyramine receptors (the known targets of amitraz) in this species. The comparison of sequences obtained from mites collected from different apiaries with different treatment regimens, showed that the amino acid substitutions N87S or Y215H in the OctβR were associated with treatment failures reported in French or U.S. apiaries, respectively. Based on our findings, we have developed and tested two high throughput diagnostic assays based on TaqMan technology able to accurately detect mites carrying the mutations in this receptor. This valuable information may be of help for beekeepers when selecting the most suitable acaricide to manage V. destructor.

     

Scavenging effect and antispasmodic activity of the essential oil of Cyclotrichium niveum

The radical scavenging and the spasmolitic activity of Cyclotrichium niveum essential oil were evaluated in vitro. It showed an IC(50) of 1750 microg/ml on DPPH method and dose dependently (0.1, 0.5 and 1 mg/ml) inhibits the contraction induced by carbachol on rabbit bladder from 15 to 100%. Moreover, it was able to inhibit the rat ileum muscle by 30 to 100%.     

Cellulose content as a selection trait in breeding for kraft pulp yield in Eucalyptus urophylla

? The aim of this study was to investigate the effectiveness of using cellulose content, measured by the diglyme-HCl method, as a selection trait in breeding programs for kraft pulp yield in Eucalyptus urophylla.

? A total of 275 trees from sixty-two families were sampled from a thinned progeny trial of E. urophylla in northern Vietnam to evaluate cellulose content from breast-height increment cores. Among those, twenty unrelated trees were felled to evaluate cellulose content and pulp yield from breast-height disk samples.

? The regression of pulp yield of disk samples on cellulose content was strong either from disks (R ² = 0.83) or increment cores (R ² = 0.69). There was no significant difference in cellulose content between the provenances. The narrow-sense within-provenance heritability of cellulose content was 0.50 and the coefficient of additive genetic variation was 3.9%. Genetic correlations between cellulose content and growth (0.28–0.45) or wood basic density (?0.02) were not significantly different from zero.

? Breast-height increment core cellulose content measured by diglyme-HCl method is under strong genetic control and can be used to rank trees for pulp yield in E. urophylla plantations. Selection for increased cellulose content would have only minor effects on growth and wood basic density.