The effects of pre-harvest dehydration on the composition of once-over harvested sweet paprika

When paprika fruits (Capsicum annuum L.) were allowed to dry in the sun, on the plant itself, before harvest, there was a considerable increase in the dry matter content of the subsequently harvested fruit, along with a decrease in the total fresh yield. The dry matter yield did not vary during the drying period, but the colour intensity of the fruit increased continuously. Early cessation of irrigation accelerated the drying rate and intensified fruit colour, but lowered the total dry matter yield.Removal of seeds, placenta parts and stalk after harvest increased fruit colour intensity but lowered yields.Leaving fruit to dry in the sun before harvest resulted in a considerable saving in transport and storage volume, as well in the amount of energy required otherwise to dry the fruit in the dehydration plant. It also opens up possibilities of once-over mechanized harvesting of high quality fruit.     

Acaricidal activity of limonene, limonene oxide and beta-amino alcohol derivatives on Rhipicephalus (Boophilus) microplus

Limonene, limonene oxide and eight beta-amino alcohol derivatives obtained by synthesis were investigated for the effect on egg hatchability and mortality rates of newly hatched larvae of the cattle tick Rhipicephalus (Boophilus) microplus. At the doses between 10mug/ml and 2.5mug/ml all the compounds were highly lethal to the larvae and some of them showed activity at lower concentrations. The effect on the eggs hatchability was observed in all the treatments.     

Cryopreservation of sperm in annual fish Austrolebias minuano (Cyprinodontiformes; Rivulidae)

The effects of the cryoprotectants dimethyl sulfoxide, glycerol and methyl glycol at different concentrations on Austrolebias minuano sperm quality parameters were evaluated in this study. The cellular kinetic parameters, determined using flow cytometry, indicated the best results with the samples cryopreserved with 7.5% methyl glycol. Dimethyl sulfoxide concentrations of 7.5% and glycerol concentrations of 10%, 12.5% and 15% demonstrated the least benefit across all evaluated sperm kinetic parameters. When assessed using flow cytometry, a concentration of 7.5% methyl glycol similarly showed better sperm kinetic parameters than 12.5% dimethyl sulfoxide. We conclude that cryoprotectants, especially methyl glycol, are effective for the preservation of sperm quality in A. minuano. However, high sensitivity of spermatozoa against glycerol was observed in these studies; thus, it is not recommended for cryopreservation purposes.     

Reaction of a heterozygous tomato hybrid bearing the Mi-1.2 gene to 15 Meloidogyne species

Many root-knot nematode (RKN) species (Meloidogyne spp.) are polyphagous and cultivated tomato (Solanum lycopersicum) is one of their preferential hosts, leading to significant losses. It is known that the dominant Mi-1.2 gene in tomato confers resistance to the three most important RKN species—M. incognita, M. javanica, and M. arenaria, and minor species—M. ethiopica, M. hispanica, and M. luci. However, little information is available about resistance of tomatoes carrying this gene to other tomato-infecting RKN species. In this study, resistance conferred by the Mi-1.2 gene/locus was evaluated against populations of 15 Meloidogyne species, employing tomato cultivars Santa Clara (homozygous recessive mi-1.2/mi-1.2, susceptible) and Debora Plus (heterozygous Mi-1.2/mi-1.2, resistant). Debora Plus was susceptible only to M. enterolobii and M. hapla, and was resistant to the other Brazilian populations of M. arenaria, M. ethiopica, M. exigua, M. hispanica, M. incognita, M. inornata, M. izalcoensis M. javanica, M. konaensis, M. luci, M. morocciensis, M. paranaensis, and M. petuniae. Mi-1.2 is located on tomato chromosome 6 within a cluster of seven homologous genes of the nucleotide-binding site leucine-rich repeat (NBS-LRR) family; further research is required to confirm if this multiple Meloidogyne spp. resistance phenotype is controlled exclusively by Mi-1.2 or by combined action of other closely linked genes. This evaluation of resistance of the Debora Plus cultivar to several Meloidogyne species suggests that the Mi-1.2 gene/locus may reduce losses induced by a wide range of Meloidogyne spp. Further studies using additional resistant cultivars and other populations of Meloidogyne spp. are needed to confirm these results.     

Laboratory testing of wood mouse and common vole sensitivity to bromadiolone,sodium selenite,and cellulose

Maintaining the numbers of wood mice and common voles at an acceptable economic level, especially during years of massive outbreaks, is a major challenge in plant protection. Efforts to reduce the negative effects of rodenticides on the environment, to improve the integrated pest control system, and to minimize risks for human and animal health require investigation of the potentials of cellulose, as a natural product, and sodium selenite as rodenticides. The present study was conducted to determine the sensitivity of these rodent species to bromadiolone (a.i. 0.005 %), sodium selenite (a.i. 0.1 and 0.05 %), and cellulose (a.i. 45 %) baits. All experiments were done using no-choice and choice feeding trials. A low acceptance of cellulose baits was found in the choice feeding trial, and the time of first deaths indicate that stress and hunger increase the death rate in both species. The taste had a negative impact on the acceptability of baits containing sodium selenite. Low bait acceptance of cellulose and sodium selenite resulted in lower mortality of both species. The acquired results indicate that bromadiolone remains a more effective solution than cellulose and sodium selenite for control of wood mice and common voles.     

Bioprospecting of Less-Polar Constituents from Endemic Brown Macroalga Fucus virsoides J. Agardh from the Adriatic Sea and Targeted Antioxidant Effects In Vitro and In Vivo (Zebrafish Model)

The endemic brown macroalga Fucus virsoides J. Agardh from the Adriatic Sea was in the focus of the present research. The volatiles of fresh (FrFv) and air-dried (DrFv) samples of F. virsoides obtained by headspace solid-phase microextraction (HS-SPME) and hydrodistillation (HD) were analyzed by gas chromatography equipped with flame ionization detector and mass spectrometry (GC-FID/MS). The major HS-FrFv compound was pentadecane (61.90–71.55%) followed by pentadec-1-ene (11.00–7.98%). In HS-DrFv, pentadec-1-ene was not present, and few lower aliphatic compounds appeared, as well as benzaldehyde and benzyl alcohol. In HD-FrFv, particularly abundant were alkenes (such as pentadec-1-ene (19.32%), or (E)-pentadec-7-ene (8.35%)). In HD-DrFv, more oxidation products were present (e.g., carbonyl compounds such as tridecanal (18.51%)). The fatty acids profile of freeze-dried sample (FdFv) after conversion to methyl esters was determined by GC-FID, and oleic acid was dominant (42.28%), followed by arachidonic acid (15.00%). High-performance liquid chromatography-high-resolution mass spectrometry with electrospray ionization (HPLC-ESI-HRMS) was used for the screening of less polar fractions (F3 and F4) of F. virsoides. Mono- and diglycerides of stearic, palmitic, oleic, and arachidonic acids were found. Terpenoids and steroids comprised the compounds C₂₀H₃₀₍₃₂₎O₂ and C₂₉H₄₈O₍₂₎. Among carotenoids, fucoxanthin was identified. Chlorophyll derivatives were also found (C₅₅H₇₄₍₇₂₎N₄O_(5-7)), dominated by pheophytin a. The antioxidant activity of the fractions was investigated by in vitro assays (oxygen radical absorbance capacity (ORAC), reduction of radical cation (ABTS•⁺), 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) assay, and ferric reducing antioxidant power (FRAP)) and by in vivo zebrafish model (along with fish embryotoxicity). In vitro experiments proved good radical scavenging abilities of F3 and F4 fractions, which were additionally supported by the protective effect against hydrogen peroxide-induced oxidative stress in zebrafish embryos.     

Novel sources of witches’ broom resistance (causal agent <Emphasis Type="Italic">Moniliophthora perniciosa</Emphasis>) from natural populations of <Emphasis Type="Italic">Theobroma cacao</Emphasis> from the Brazilian Amazon

Witches’ broom is a severe disease of Theobroma cacao L. (cacao), caused by the basidiomycete Moniliophthora perniciosa. The use of resistant cultivars is the ultimate method of control, but there are limited sources of resistance. Further, resistance from the most widely used source (‘Scavina 6’) has been overcome after a few years of deployment. New sources of resistance have been intensively searched for in the Amazon basin. Here, we evaluated for witches’ broom resistance, cacao accessions from various natural cacao populations originally collected in the Brazilian Amazon. Resistance of 43 families was evaluated under nursery and/or field conditions by artificial or natural infection, respectively, based on disease incidence. Screening for resistance by artificial inoculation under nursery conditions appeared to be efficient in identifying these novel resistance sources, confirmed by natural field evaluation over a nine-year period. The increase in natural field infection of ‘Scavina 6’ was clearly demonstrated. Among the evaluated families with the least witches’ broom incidence, there were accessions originally collected from distinct river basins, including the Jamari river (‘CAB 0371’; ‘CAB 0388’; ‘CAB 0392’; and ‘CAB 0410’); Acre (‘CAB 0169’); Javari (‘CAB 0352’); Solimões (‘CAB 0270’); and from the Purus river basin, the two most outstanding resistant accessions, ‘CAB 0208’ and ‘CAB 0214’. The large genetic diversity found in cacao populations occurring at river basins from Acre and Amazonas states, Brazil, increased the chance that the selected resistant accessions would be genetically more dissimilar, and represent distinct sources of resistance to M. perniciosa from ‘Scavina 6’.     

Castor beans hulls as a replacement for Tifton 85 hay in lamb diets

The objective of this study was to evaluate the effect of replacing Tifton 85 hay (0, 33, 66, or 100 %) with by castor bean hulls on the intake and nutrient digestibility and performance of 28 noncastrated lambs, averaging 7 months in age, 19.5?±?2.0 kg average live weight, fed on diets based on forage cactus. The animals were housed in individual pens for 100 days. The digestibility trial occurred 40 days after the start of the performance using LIPE® as an external indicator for estimating fecal dry matter production. The replacement of hay with Castor beans hulls linearly decreased the intakes of dry matter, neutral detergent fiber, organic matter, and crude protein and reduced the digestibility coefficients of the dry matter, neutral detergent fiber, organic matter content, crude protein, and total digestible nutrient content. The hot carcass and true carcass yields were not influenced by the treatments and the feed conversion increased linearly. The empty body weight, live weight at slaughter, hot and cold carcass weights, total gain, and average daily gain decreased linearly with the replacement. The replacement of Tifton 85 hay with castor bean hulls reduced the intake of dry matter, crude protein and energy, consequently reducing the performance of the animals. However, as the regression coefficients were of low magnitude, data were subjected to analysis of variance and means were compared using the Dunnett test with diet without castor bean hulls set as the control treatment. The Tifton 85 hay can be replaced up to 66 % by castor bean hulls in finishing diets for lambs.