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The fungicide difenoconazole, widely used to reduce the negative impacts of fungi diseases on areas with intensive farming, can reach freshwater systems causing deleterious effects on nontarget organisms. The acute and chronic toxicity of a commercial formulation containing 250 g L-1 of difenoconazole (Prisma®) as the active ingredient was assessed in the freshwater planarian Girardia tigrina. The endpoints evaluated were feeding rate, locomotion, regeneration, and sexual reproduction of planarians. The estimated 48 h LC50 of the commercial formulation on planarians expressed as the concentration of the active ingredient difenoconazole was 47.5 mg a.i.L-1. A significant decrease of locomotion (LOEC = 18.56 mg a.i.L-1), delayed regeneration (LOEC = 9.28 mg a.i.L-1), and sexual reproduction impairment, i.e., decreased fecundity and fertility rates (LOEC ≤ 1.16 mg a.i.L-1) were observed on planarians exposed to sublethal concentrations of the formulation. This study demonstrated the importance of using reproductive, physiological, and behavioral parameters as more sensitive and complementary tools to assess the deleterious effects induced by a commercial formulation of difenoconazole on a nontarget freshwater organism. The added value and importance of our research work, namely, the impairment of sexual reproduction of planarians, contributes to the development of useful tools for ecotoxicology and highlights the fact that those tools should be developed as guidelines for testing of chemicals. Our results showed that the use of reproductive parameters of Girardia tigrina would help to complement and achieve a better assessment of the risk posed by triazole fungicides to freshwater ecosystems.

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The chloroplast (cp) is an essential organelle in higher plants. The genes of the plastome are well suited to infer phylogenetic relationships among taxa. In this study, we report the assembly of the cp genome of Artocarpus altilis and its phylogeny among species from Moraceae family. The cp genome of A. altilis was 160,822 base pair (bp) in length, comprising one large single-copy region of 88,692 bp, one small single-copy region of 19,290 bp, and a pair of inverted repeat regions (IRs) of 26,420 bp. A total of 113 different genes were predicted, including 79 protein-coding genes, 30 tRNA genes, and four rRNA genes. The phylogenetic analysis of 19 species belonging to the Moraceae family confirmed the phylogenetic proximity of the genus Artocarpus and Morus and the genetic similarity of A. camansi and A. altilis.

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Chlorine plays a primary role in the disinfection of drinking water and wastewater due to its effectiveness as a biocide; however, there is evidence of the formation of toxic byproducts from its application, and this has promoted the search for alternatives. Alternative disinfectants can be effective in the inactivation of pathogenic microorganisms and are less damaging to human health and aquatic ecosystems. However, more information is needed on the effect of residual concentrations on the environment. This work compares the ecotoxicological effects of PAA disinfectants and the active chlorine of calcium hypochlorite in relation to the organism Dugesia tigrina (planaria), in terms of the acute effects: LC50, and chronic effects: feeding, locomotion, regeneration, reproduction and fertility. The results indicated that the active chlorine was more toxic than PAA, with LC50 (96 h) of 2.63 mg.L-1 and 3.16 mg.L-1, respectively. Sub-lethal exposure to active chlorine was more toxic when compared to PAA, and there was evidence of significantly reduced feeding and locomotion, causing a greater delay in regeneration and impairment in reproduction and fertility. The results allowed the comparison of the two disinfectants using half-life constants of the compounds and the lowest observed effect level (LOEC) of the oxidants. Chlorine represents a greater risk to the ecosystem for a longer period. The results obtained in this study can help in the establishment of discharge limits for PAA in water bodies.

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Filamentous fungi from the genus Trichoderma are commonly found in soil. They are considered facultative mycoparasites, and are antagonists of other fungi such as the cultivar of leaf-cutting ants (Leucoagaricus gongylophorus). The aim of the present study was to bioprospect Trichoderma spp. from different soils collected from Gurupi, Tocantins, Brazil, for antagonistic effects against the mutualistic fungus of leaf-cutting ants. To isolate filamentous fungi, samples were collected from six locations. Preliminarily, isolates were identified by morphological analysis as belonging to Trichoderma. Trichoderma spp. had their internal transcribed spacer region (ITS) of ribosomal RNA genes (rRNA) sequenced to confirm species-level taxonomy. L. gongylophorus was isolated from a laboratory ant colony. Antagonistic properties of seven isolates of Trichoderma against L. gongylophorus were measured using paired disks in Petri dishes with potato dextrose agar medium (PDA). All Trichoderma isolates inhibited the growth of L. gongylophorus in Petri dishes. Isolate 2 of Trichoderma spirale group exhibited slow mycelial growth in the Petri dish, and a high rate of inhibition against L. gongylophorus. This isolate is a promising fungus for field tests of biological control methods for leaf-cutting ants.

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Sampling plans are essential components of integrated pest management programs. The thrips Frankliniella schultzei (Trybom) (Thysanoptera: Thripidae) is an important pest of watermelon crops. Despite the importance of sampling plans and of F. schultzei as a pest of watermelon crops, no research has been previously conducted on this subject for this crop. The objective of this work was to create a standardized sampling plan for F. schultzei in watermelon crops. Over two consecutive years, weekly samplings were performed in commercial watermelon crops. The aim of these assessments was to select the best sampling unit and the best sampling technique for F. schultzei assessment and to determine the number of samples necessary for a standardized sampling plan for this pest. In watermelon crops in the vegetative, flowering, and fruiting stages, the ideal location for sampling F. schultzei was the most apical leaf of the branches. The best sampling technique was a direct count of F. schultzei individuals. The F. schultzei sampling plan involved the evaluation of 69 samples per plot. The execution duration of this sampling plan in 1- to 15-ha plots was <1 h and was inexpensive (

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