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Introduction: Soybean is a significant export product for several countries, including the United States and Brazil. There are numerous varieties of soybean. Among them, a genetically modified type known as INTACTA RR2 PRO™ has been designed to demonstrate resistance to glyphosate and to produce toxins that are lethal to several species of caterpillars. Limited information is available on the use of Trichoderma harzianum and Bacillus subtilis to promote plant growth and their impact on the plant microbiome. Methods: This study aimed to evaluate the effects of these microorganisms on this soybean cultivar by analyzing parameters, such as root and shoot dry matter, nutritional status, and root and soil microbial diversity. Results: The results indicated that treatments with B. subtilis alone or in combination with T. harzianum as seed or seed and soil applications significantly enhanced plant height and biomass compared to the other treatments and the control. No significant differences in phosphorus and nitrogen concentrations were detected across treatments, although some treatments showed close correlations with these nutrients. Microbial inoculations slightly influenced the soil and root microbiomes, with significant beta diversity differences between soil and root environments, but had a limited overall impact on community composition. Discussion: The combined application of B. subtilis and T. harzianum particularly enhanced plant growth and promoted plant-associated microbial groups, such as Rhizobiaceae, optimizing plant-microbe interactions. Furthermore, the treatments resulted in a slight reduction in fungal richness and diversity. [ABSTRACT FROM AUTHOR]

Bees can be exposed to pesticides when visiting crops or plants in adjacent areas affected by spray drift. Among pesticide categories, fungicides tend to be considered relatively safe, though they also can negatively affect pollinators. Most evidence of damage by fungicides to bees comes from laboratory tests; there is little information concerning contamination levels in the field. We examined exposure of honey bees (Apis mellifera L.) (Hymenoptera: Apidae) and a common Brazilian native species of social stingless bees (Scaptotrigona postica Latreille; Hymenoptera: Apidae), which is about a third the size of a honey bee, to a commercial fungicide (Fox Xpro), with three active ingredients (trifloxystrobin, bixafen, and prothioconazole), applied to crops they often visit according to label directions. A spraying apparatus mounted on tracks in a laboratory spray room was used to simulate field conditions. Soybean and cotton plants grown in pots were transferred to the spray room when the plants were in flower. Anaesthetized bees were attached with insect pins at the top and middle of the plants, on leaves and flowers. The fungicide was applied using fine or coarse droplets. The amounts of the individual active ingredients absorbed by bees were then quantified. Concentrations of trifloxystrobin were highest in both honey bees and stingless bees, followed by bixafen, and then prothioconazole, which was detected in the bees at much lower levels. Overall, bees at the top of the plants and those sprayed with fine droplets absorbed more pesticide. As a function of body mass, the stingless bees were more heavily contaminated than the larger honey bees. Tests using spraying systems that simulate field conditions can better estimate the actual doses that contaminate bees to help determine the impact of fungicides and other pesticides applied to crops. [ABSTRACT FROM AUTHOR]

Simple Summary: In many regions of the world, foraging bees encounter an environment with an inadequate supply of nutrients compared with the colonies' demands, as well as exposure to pesticides used to combat plant pests and diseases, including fungicides which historically were considered innocuous for bees. The use of pesticide mixtures can increase the risk for bees, especially when limited foraging leads to nutritional deficiencies. In our study, we compared the effects of the commercial fungicides bixafen, prothioconazole, and trifloxistrobin, alone and in combination, on foraging honey bees that were collected from colonies with supplemented or restricted food availability. For this purpose, we assessed the expression of health-related genes, including antioxidant genes (SOD-1, CAT, and GPX-1), detoxification genes (GST-1 and CYP306A1), the storage protein gene vitellogenin, and immune system antimicrobial peptide genes (defensin-1, abaecin, hymenoptaecin, and apidaecin) using real-time PCR. All three fungicides caused alterations in the expression of these genes, especially the mixture with the three active ingredients, both in bees from colonies with supplemented feeding and those from colonies subjected to food restriction. The effect of fungicide exposure on gene expression was dependent on bees' nutritional status, which suggests that adequate nutrition can help counteract the effects of fungicides on bees. The aim of this study was to evaluate whether alterations in food availability compromise the metabolic homeostasis of honey bees exposed to three fungicides alone or together. Ten honey bee colonies were used, with half receiving carbohydrate-protein supplementation for 15 weeks while another five colonies had their protein supply reduced with pollen traps. Subsequently, forager bees were collected and exposed by contact to 1 or 7 µg of bixafen, prothioconazole, or trifloxystrobin, either individually or in combination. After 48 h, bee abdomens without the intestine were used for the analysis of expression of antioxidant genes (SOD-1, CAT, and GPX-1), detoxification genes (GST-1 and CYP306A1), the storage protein gene vitellogenin, and immune system antimicrobial peptide genes (defensin-1, abaecin, hymenoptaecin, and apidaecin), through real-time PCR. All fungicide treatments induced changes in gene expression, with bixafen showing the most prominent upregulation. Exposure to 1 µg of each of the three pesticides resulted in upregulation of genes associated with detoxification and nutrition processes, and downregulation of immune system genes. When the three pesticides were combined at a dose of 7 µg each, there was a pronounced downregulation of all genes. Food availability in the colonies affected the impact of fungicides on the expression of the studied genes in forager bees. [ABSTRACT FROM AUTHOR]

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The aim of this research was to assess if the supplementation of the silkworm diet with soybean water soluble extract (WSE) interferes on the consumption of mulberry leaves (Morus alba L.) by the caterpillars and on cocoon production. The experimental design was completely randomized in factorial arrangement 4x5, with four mulberry varieties ('IZ64', 'IZ56/4', and 'FMSM' 'FM86') and five diets (untreated control leaves, leaves moistened with water and leaves enriched with WSE, in three levels). The WSE was sprayed on the leaves with water as dispersing agent. The consumption was measured by the difference between the quantity of food provided and the amount that was not consumed by the larvae. The consumption was presented quadratic form, which decreased as the WSE was added on diet. There was interaction between cultivar and diets. Silkworm fed diets containing leaves of mulberry with addition of 10% of crude protein through WSE improved the quality of cocoons with utilization of 'IZ56/4' and 'FMSM' cultivars. The sprayed of WSE on leaves of 'IZ64' cultivar decreased production of cocoons. Silkworm fed with leaves without supplementation produced heavier cocoons shells of the 'IZ64' and 'FMSM' cultivars. Water sprayed on leaves provided higher weight of cocoons shells from 'FM86' cultivar. The WSE supplementation in diets decreases consumption of silkworm. The WSE sprayed influences cocoon production depending on the cultivar. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the occurrence of compensatory answer on productive performance of Nile tilapia Oreochromis niloticus juveniles, GIFT line, submitted to different feeding strategies. It was used 135 juveniles tilapias distributed in nine 100L polyethylene tanks each. The tested strategies were the control group (fed everyday), group fed for 5 days followed by 2 days of food restriction (5A/ 2R) and group fed for 4 days followed by 3 days of food restriction (4A/3R). Were evaluated physical chemical water parameters e growth performance. Results were submitted to an analysis of variance and averages compared by Tukey test 5%. Water quality, condition factor and feed conversion were not influenced by feeding strategy. Group fed 5A/2R strategy showed final weight, weight gain and specific growth rate similar to group continually fed (7.8 e 9.2g; 6.4 e 7.8g e 2.7 e 3.0% day-1, for final weight, weight gain and specific growth rate, respectively). The strategy 4A/3R showed the poorest productive performance. Strategy 5A/2R can be used in Nile tilapia juveniles feeding without damage to the fish productive performance, allowing a reduction of up to 22.5% on the feed quantity offered. [ABSTRACT FROM AUTHOR]