Novel Natural Compounds and Their Anatomical Distribution in the Stinging Fireworm Hermodice carunculata (Annelida)

Increasing evidence in the field of bioprospection fosters the necessity of studying poorly investigated poisonous marine invertebrates to expand knowledge on animal venom biology. Among marine annelids, amphinomid fireworms are notorious for their bearded trunk equipped with a powerful stinging capacity. Here, a methodological workflow based on analytical chemistry techniques (compound isolation followed by mass spectrometry and spectroscopy analyses) was applied to gain new insights, leading to the identification and structural elucidation of an array of natural products from Mediterranean specimens of Hermodice carunculata. Eight betaine-derived unprecedented compounds, named “carunculines”, were detected, bearing two terminal ammonium groups tri-and disubstituted at the Cα (A, B) and a series of different alkyl chains (I–VIII). The mixture of chemicals was found in all the body parts of H. carunculata, supporting a mechanism of action triggered by their vehiculation inside the dorsal chaetae, and subsequent injection when chaetae break off on contact. Preliminary investigations to understand adaptive features were also performed, showing a trend in carunculine abundance that fits into the evolutionary history of these worms. These findings shed light on the chemical ecology of amphinomids, giving reasons for the success of H. carunculata in benthic environments and providing promising novel metabolites for biotechnological implications.     

Side effects of botanical insecticides on predatory mite Amblyseius andersoni (Chant)

The effects of the botanical insecticides Biopiren plus, Piresan plus and Neemazal T/S on the predatory mite Amblyseius andersoni (Chant) were tested under laboratory, semi-field, and field conditions. The tests carried out in the laboratory allowed detection of the direct toxicity on eggs and females as well as the effects on fecundity, whereas semi-field trials assessed their residual toxicity. In laboratory and semi-field tests, pyrethrins, particularly Piresan plus, proved to have the highest toxicity with E value, concerning both female mortality and fecundity, of 100?% and 45?%, respectively. The same product tested in the field only caused a significant reduction in the phytoseiid population shortly after the treatment. The relevant escape rate registered in semi-field tests could explain the lack of phytoseiid eradication in the field after treatment with pyrethrins.     

Principles for regulatory testing and interpretation of semi-field and field studies with non-target arthropods

This paper is a guidance document for side-effect testing with plant protection products on non-target arthropods under semi-field and field conditions. The principles, methods, endpoints and interpretation of non-target arthropod semi-field and field trials which should be conducted for registration of plant protection products in the European Union are presented and discussed. The recommendations presented reflect the opinions of the experts from authority, academia, industry and consulting which participated at the IOBC (International Organisation of Biological Control), BART (Beneficial Arthropod Regulatory Testing) group and EPPO (European Plant Protection Organisation) Joint Initiative workshop held in Versailles (France) on the 25–26 October, 1999.     

Effect of chelating and antioxidant agents on morphology and DNA methylation in freeze-drying rabbit (Oryctolagus cuniculus) spermatozoa

Freeze-drying (FD) has been exhaustively tried in several mammalian species as an alternative technique to sperm cryopreservation, but few studies have been done in rabbits (Oryctolagus cuniculus). The main objective of this study was to compare the protective effect of various antioxidants added to EDTA medium on structural and functional components of FD rabbit spermatozoa and on their status of global DNA methylation. FD media used were composed of basic FD medium (10 mM Tris-HCl buffer and 50 mM NaCl) supplemented with either 50 mM EDTA alone (EDTA) or added with 105 µM of rosmarinic acid (RA, EDTA-RA) or 10 µM of melatonin (MLT, EDTA-MLT). The effect of each medium on the preservation of FD spermatozoon structure was evaluated with light and scanning electron microscopy (SEM). Global DNA methylation was quantified in all FD sperm samples as well as in fresh spermatozoa. Morphologically, fracture points were evidenced in the neck, mid and principal piece of the spermatozoon tail. No differences in spermatozoon fracture points were evidenced among FD treatments: intact spermatozoa were the largest (p < .01) category, whereas the most frequent (p < .01) injury was the neck fracture, resulting in tailless heads. At SEM, the head of spermatozoa showed a well-conserved shape and intact membrane in all treatments. DNA methylation status was the same in all FD treatments. In conclusion, supplementation of EDTA, EDTA-RA and EDTA-MLT during FD preserved rabbit sperm morphological integrity and methylation status as well. Therefore, the difficulty of getting viable offspring using FD semen is likely unrelated to the impact of the lyophilization process on DNA methylation and morphology of lyophilized spermatozoa.     

Modeling perspective of the deforestation impact in stream water quality of small preserved forested areas in the amazonian rainforest

A long-term predictive model, MAGIC, was applied to a Central Amazonian catchment area to illustrate large scale deforestation effects on ‘islands’ of preserved areas, for the situations with and without climate changes. In addition, model sensitivity in response to different organic matter levels in the soil and stream waters as well as to different Al solubility constants was evaluated. The model output was strongly dependent on the chosen values of organic matter concentration and Al solubility constant. Application of the model to a 30 yr deforestation program revealed increases in streamwater ionic concentrations with or without climate change, although streamwater ionic concentrations were predicted to be higher as a consequence of climate change. On the centennial scale, streamwater ionic concentrations reach a new equilibrium, with concentrations higher than those prior to the surrounding deforestation. With the assumed increased cation deposition to the preserved forest areas, soil exchangeable cation concentrations increase with time and aluminum is released to solution. At the end of the simulated deforestation program, SO ₄ ^2? in the preserved areas began to be released to streamwater, inducing acidification. Application of the MAGIC model makes possible to estimate, for the rainforest environment, water quality changes as a function of different climate and land use changes.     

Improving production and health of seed potato stocks in Italy

Summary When nodal explants from sprouts grown from virus-free tubers of ten cultivars were propagated on half-strength Murashige and Skoog medium, cvs Arsy, Nicola, Kennebec and Spunta grew best. Rooted plantlets, 5–8 cm tall, were transplanted from culture vessels into pots containing soil, vermiculite and sand. They were weaned by growing in a glasshouse for about three weeks. Over 90% of the plantlets survived and these were then planted in the field and protected against aphids by a double screen (a large tunnel covering four adjacent small tunnels) and chemical treatments. Prebasic seed tubers thus obtained were virus-free and production ranged from 49.9 t.ha⁻¹ (‘Monalisa’) to 27.1 t.ha⁻¹ (‘Majestic’). A survey showed that ‘elite’ (near virus-free) seed could be produced from prebasic seed by early planting and early haulm killing regardless of location, but late planting on the plains and normal planting dates on the mountains resulted in 1 to 5% virus infection levels acceptable only for certified seed.     

Principles for regulatory testing and interpretation of semi-field and field studies with non-target arthropods

This paper is a guidance document for side-effect testing with plant protection products on non-target arthropods under semi-field and field conditions. The principles, methods, endpoints and interpretation of non-target arthropod semi-field and field trials which should be conducted for registration of plant protection products in the European Union are presented and discussed. The recommendations presented reflect the opinions of the experts from authority, academia, industry and consulting which participated at the IOBC (International Organisation of Biological Control), BART (Beneficial Arthropod Regulatory Testing) group and EPPO (European Plant Protection Organisation) Joint Initiative workshop held in Versailles (France) on the 25–26 October, 1999.     

Side effects of botanical insecticides on predatory mite Amblyseius andersoni (Chant)

The effects of the botanical insecticides Biopiren plus, Piresan plus and Neemazal T/S on the predatory mite Amblyseius andersoni (Chant) were tested under laboratory, semi-field, and field conditions. The tests carried out in the laboratory allowed detection of the direct toxicity on eggs and females as well as the effects on fecundity, whereas semi-field trials assessed their residual toxicity. In laboratory and semi-field tests, pyrethrins, particularly Piresan plus, proved to have the highest toxicity with E value, concerning both female mortality and fecundity, of 100% and 45%, respectively. The same product tested in the field only caused a significant reduction in the phytoseiid population shortly after the treatment. The relevant escape rate registered in semi-field tests could explain the lack of phytoseiid eradication in the field after treatment with pyrethrins.     

Side effects of botanical insecticides on predatory mite Amblyseius andersoni (Chant)

The effects of the botanical insecticides Biopiren plus, Piresan plus and Neemazal T/S on the predatory mite Amblyseius andersoni (Chant) were tested under laboratory, semi-field, and field conditions. The tests carried out in the laboratory allowed detection of the direct toxicity on eggs and females as well as the effects on fecundity, whereas semi-field trials assessed their residual toxicity. In laboratory and semi-field tests, pyrethrins, particularly Piresan plus, proved to have the highest toxicity with E value, concerning both female mortality and fecundity, of 100% and 45%, respectively. The same product tested in the field only caused a significant reduction in the phytoseiid population shortly after the treatment. The relevant escape rate registered in semi-field tests could explain the lack of phytoseiid eradication in the field after treatment with pyrethrins.     

Efficiency and soil contamination during underground application of insecticides: control of leaf-cutting ants with thermal foggers

There are several types of potential hazards associated with the use of pesticides, among them, soil contamination during their underground application. The trade-off between control effectiveness and soil contamination can be observed during the control of leaf-cutting ants using thermal fogs in South American agricultural and forest plantations. This work was aimed at simultaneously assessing fog penetration into the soil around the application point, as a measure of contamination, and fog presence inside nest chambers of the grass-cutting ant Atta capiguara, as a measure of control effectiveness. For that, we have implanted fog sensors both into the soil around the application point and inside fungus chambers. Results showed that thermal fogging can be considered as an effective way for controlling leaf-cutting ants, since fog actually entered into the fungus chambers of A. capiguara after an average of 7 min. Nevertheless, after 3 min, i.e. long before reaching the fungus chambers, fog penetrated laterally 0.5 m into the soil, and at a depth of 1 m. At the time the fungus chambers were reached, the fog extended over 1.5 m across the soil. Thus, assuming a radial spread of fog, the total volume of contaminated soil around the application point averaged almost one cubic meter. Given the need of using thermal fogging for the control of Atta leaf-cutting ants due to both the economic damage they produce and the lack of other effective control methods under particular circumstances, associated environmental costs of thermal fogging as well as possible mitigation measures are discussed.