Based on the analysis of the intron polymorphism of β-tubulin genes, the genetic variability of old Quercus robur L. trees from “Holosiivsky” NPP was investigated. The genotyping of 55 old Q. robur ...trees was carried out; 40 polymorphic and one monomorphic (about 880 bp) TBR fragments were found. High frequency (70–90%) of occurrence of fragments with an approximate molecular weight of 275, 490, 500, and 1110 bp was observed.The genetic polymorphism of old Q. robur trees was assessed as quite high: РІС is 0.22 – 0.39, the effective number of alleles per locus was 1.174–1.268. The Shannon information index was in the range of 0.204–0.269.The geographical differentiation of the genetic structure of centuries-old oak trees from “Holosiivsky” NPP was not pronounced. The share of inter-selection genetic variability (AMOVA) accounts for about 6% of genetic variability, and the geographic component – about 1%. Around 93% of genetic variability is concentrated on the individual level. Using the ТВР method, we found that Q. robur forest stands do not have a stabilized genetic and visible spatial structure, but at the same time they possess a sufficiently large genetic diversity.
Spinosyn insecticides are widely used in conventional berry production, and spinosad is regarded as the most effective insecticide for managing Drosophila suzukii (Matsumura) (Diptera: ...Drosophilidae), spotted-wing drosophila, in organic berry crops. Following the 2017 identification of spinosad resistance in caneberry fields in the Watsonville area, Santa Cruz Co., California, we conducted a study to examine the seasonal and annual susceptibility of D. suzukii over a three-year period. Adult flies were collected from two conventional and two organic caneberry fields in the Monterey Bay region, California, at ‘early’, ‘middle’, and ‘late’ time points during the 2018–2020 growing seasons, and their susceptibility to spinosad was assessed. Results demonstrated that spinosad susceptibility in the D. suzukii field populations generally decreased during the fruit production season (from June through November), and over consecutive seasons. LC50 values of adults from the conventional sites were determined to be as high as 228.7 mg l–1 in 2018, 665.6 mg l–1 in 2019, and 2700.8 mg l–1 in 2020. For the organically managed fields, LC50s of adults were as great as 300.0 mg l–1 in 2018, 1291.5 mg l–1 in 2019, and 2547.1 mg l–1 in 2020. Resistance ratios based on the LC50 values were as high as 10.7-, 13.2-, and 16.9-fold in 2018, 2019, and 2020, respectively. These results should serve as a caution for growers in other production areas, facilitate informed choice of insecticides used in D. suzukii management, and emphasize the need to develop effective insecticide resistance management strategies for this insect.
The administration of antiretrovirals (ARVs) for HIV pre-exposure prophylaxis (PrEP) is highly efficacious and may benefit from new long-acting (LA) drug delivery approaches. This paper describes a ...subcutaneous, reservoir-style implant for the LA delivery of tenofovir alafenamide (TAF) and documents the preclinical assessment of implant safety and pharmacokinetics (PK) in New Zealand White (NZW) rabbits (3 groups of
= 5), beagle dogs (2 groups of
= 6), and rhesus macaques (2 groups of
= 3). Placebo implants were placed in rabbits (
= 10) and dogs (
= 12). Implant parameters, including selection of the TAF form, choice of excipient, and PCL formulation were tuned to achieve targeted concentrations of the active anabolite of TAF, tenofovir diphosphate (TFV-DP), within peripheral blood mononuclear cells (PBMCs) and mucosal tissues relevant to HIV transmission. Sustained concentrations of TFV-DP in PBMCs over 100 fmol/10
cells were achieved in all animal species indicating that the implants effectively delivered TAF for 3-6 months. Unlike placebo implants without TAF, all active implants resulted in local adverse events (AEs) proximal to the implant ranging in severity from mild to moderate and included dermal inflammation and necrosis across all species. Despite these AEs, the implant performed as designed and achieved a constant drug release profile, supporting the continued development of this drug delivery platform.
Variability for the loci GOT and GDH of seed embryos of three subpopulations of Pinus sylvestris L. exposed to the emissions from the chemical enterprise manufacturing nitrogen fertilizers was ...studied during four years. The trend to heterozygosity reduction and increased occurrence of the cases of significant deviation of the distribution of genotypes from the theoretically expected one was shown.
The variability in four GOT and GDH loci of the seed progeny (embryos) of three
Pinus sylvestris
L. subpopulations, differentially exposed to the action of emissions of a large chemical complex ...producing nitrogen fertilizers, has been studied for four years. A trend toward a decrease in the heterozygosity and an increase in the frequency of cases with significant deviations of the observed genotype distribution from the theoretically expected one were observed in the progeny of plants from a degrading and digressing subpopulation in an area of acute action of aeropollutants (0.3–2 km).
Amyelois transitella (Walker) (Lepidoptera: Pyralidae), the navel orangeworm, is a highly polyphagous economic pest of almond, pistachio, and walnut crops in California. Increasing demand for these ...crops and their rising economic value has resulted in substantial increases of insecticide applications to reduce damage to acceptable levels. The effects of piperonyl butoxide (PBO), a methylenedioxyphenyl compound that can act as a synergist by inhibiting cytochrome P450-mediated detoxification on insecticide metabolism by A. transitella, were examined in a series of feeding bioassays with first-instar A. transitella larvae from a laboratory strain. PBO, however, can have a variety of effects on metabolism, including inhibition of glutathione-S-transferases and esterases and induction of P450s. In our study, PBO synergized the toxicity of acetamiprid, γ-cyhalothrin, and spinosad, suggesting possible involvement of P450s in their detoxification. In contrast, PBO interacted antagonistically with the organophosphate insecticide chlorpyrifos, reducing its toxicity, an effect consistent with inhibition of P450-mediated bioactivation of this pesticide. The toxicity of the anthranilic diamide insecticide chlorantraniliprole was not altered by PBO, suggestive of little or no involvement of P450-mediated metabolism in its detoxification. Because a population of navel orangeworm in Kern County, CA, has already acquired resistance to the pyrethroid insecticide bifenthrin through enhanced P450 activity, determining the effect of adding a synergist such as PBO on detoxification of all insecticide classes registered for use in navel orangeworm management can help to develop rotation practices that may delay resistance acquisition or to implement alternative management practices where resistance is likely to evolve.
The genetic variability at 12 allozyme (ten were found to be polymorphic) loci was studied in the archive-clone plantation of 23 plus-trees of
Pinus sylvestris
and their seed progeny in the southeast ...of Ukraine. More than half of the clones possessed four to eight heterozygous loci, while their seed progeny was characterized by a lower degree of variation as compared with maternal trees. Seed progeny was obtained from high outcrossing rate (
t
m
= 95%). The clone progeny was characterized by a high rate of distortions of allele segregation in megagametophytes and a high percentage of significant deviations in distribution of genotypes of seed embryos from that theoretically expected in accordance with the Hardy-Weinberg ratio.
Genetic variation at 12 allozyme loci (10 of them being polymorphic ones) has been studied in the archive-clone plantation of 23 Pinus sylvestris plus-trees and their seed progeny in the south-east ...of Ukraine. More than a half of clones had 4-8 heterozygous loci, whereas their seed progeny was marked by a lower variation than maternal trees. Seed progeny was obtained at a high outcrossing rate (t(m) = 95%). The clone progeny was characterized by a high percentage of abnormal allele segregation in megagametophytes. There was also a high frequency of significant deviation in distribution of seed embryo genotypes from the theoretically expected one according to the Hardy-Weinberg law.
A comparative analysis of the allozyme variation in 18 loci of three steppe natural populations of
Pinus sylvestris
L. and a sample of 36 resistant trees from artificial stands at locations affected ...by root fungus (
Heterobasidion annosum
(Fr.) Bref.) is conducted. The resistant trees are characterized by lowest percentages of polymorphic allozyme loci, a fewer number of alleles, and number of genotypes close to the mean-population number, as well as a level of observed and expected heterogeny. In terms of composition and frequencies of multi-loci genotypes (Dia-1, Lap-1, Acp) that are responsible for the greatest contribution to the partitioning of the stands studied, the sample of resistant trees differs markedly from the natural populations.
Comparative analysis of allozyme variability was carried out by 18 loci from such tree-groups as 3 Pinus sylvestris L. natural steppe populations and a sample of 36 resistant trees from artificial ...stands in root fungus (Heterobasidion annosum (Fr.) Bref.) damage centres. Resistant trees are characterized by the least portion of polymorphic allozyme loci, by allele and genotype number, and by similar to midpopulational level observed and expected heterozigosity. Resistant tree sample differed from natural populations on composition and frequencies of multi-locus genotypes Dia-1, Lap-1, Acp, which are making the most contribution to researched tree-stands subdivision.
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