Aedes aegypti (Ae. aegypti) is a competent vector for transmitting important viral diseases such as yellow fever, dengue, chikungunya, and Zika. Several strategies have been applied to avoid Ae. aegypti proliferation by using environmental management, biological, and chemical approaches. However, the development of new methods for effective control of the insect vector population is still needed. Photodynamic control is an alternative way to control the vector population by using a physical approach based on the larval phototoxicity of a photosensitizer. In this context, the present study evaluated the use of eosin-methylene blue (EMB) as a new photosensitizer for photodynamic control of Ae. aegypti larval populations. The photodynamic assays were performed submitting Ae. aegypti third-instar larvae to different EMB concentrations (0.0, 0.5, 1.0, 5.0, 10.0, 50.0, and 100.0 µg mL⁻¹) in combination of three different light doses (24.3, 48.6, and 97.2 J cm⁻²) under either white-light radiation from RGB LEDs or sunlight. The results demonstrated that EMB presented a rapid internalization into the larvae and was phototoxic. The photodynamic action induced 100% of larval mortality after about 40 min of sunlight irradiation even using low EMB concentration (0.5 µg mL⁻¹). The findings reveal EMB as an effective photoactive compound to control larval populations of Ae. aegypti by photodynamic process induced by either sunlight or white-light from RGB LEDs.

A new species of mealybug from Chile, Pseudococcus meridionalis Prado sp. n., is described and illustrated based on the morphological and molecular characterization of adult females. This species belongs to the “Pseudococcus maritimus” complex and displays a wide host plant range, including Japanese pear, persimmon, pomegranate, pear and grape.

A cochonilha Dysmicoccus brevipes (Cockerell) (Hemiptera: Pseudococcidae) é uma das principais pragas em cultivos de abacaxi e os estudos biológicos desse inseto em diferentes cultivares são uma necessidade. Objetivou-se com este trabalho avaliar o desenvolvimento dessa cochonilha em duas cultivares de abacaxi, Pérola e Cayenne. O experimento foi conduzido em câmara climatizada a 25 ± 1ºC, 70 ± 10% UR e fotofase de 12 horas. As plantas de abacaxi foram reproduzidas in vitro, transplantadas para vasos (250 mL) e aclimatadas em casa-de-vegetação. Ninfas com até um dia de vida foram confinadas em gaiolas de PVC (1 cm de diâmetro), e fixadas em folhas de ambas as cultivares. Não foram detectadas diferenças no desenvolvimento de D. brevipes nos dois substratos alimentares utilizados. O desenvolvimento ninfal de fêmeas e machos de D. brevipes foi 39,9 e 32,0 dias na cv. Pérola e 38,5 e 32,4 dias na cv. Cayenne, respectivamente. A sobrevivência da fase ninfal foi 32,3 e 40,5%; a razão sexual, 0,39 e 0,33; e a longevidade de fêmeas, 20,3 e 26,1 dias nas cvs. Pérola e Cayenne, respectivamente.

In modern agriculture, the quest for increased productivity necessitates a comprehensive understanding of crop conditions. A critical component of this is soil analysis, which is essential for developing effective strategies that enhance productivity while minimizing environmental impacts and reducing production costs. The soil apparent electrical conductivity (ECa) sensor is a valuable tool in precision agriculture, offering a cost-effective and time-efficient alternative for soil analysis. This study aimed to develop a portable ECa sensor for diverse applications in agriculture and test it under field conditions aiming for its application as a precision agriculture tool. The development process was divided into four key stages: sensor construction, electronic circuit design, implementation of the embedded control program, and both laboratory and field testing in agricultural settings. The sensor was designed to expedite measurements, with a focus on achieving precision and accuracy in the electronic circuit. Data collected using the ECa meter were analyzed under various conditions, including dry and moist soils, and in a white oat production field. Spatial variability was assessed, leading to the generation of ECa management zone maps. The developed sensor demonstrated ease of operation, rapid measurement capabilities, and performance comparable to commercial meters within the operating range. The findings indicate that the portable ECa meter is a viable tool for analyzing soil spatial variability in precision agriculture systems.