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The application of synthetic insecticides is the main strategy used to reduce the damage caused by the diamondback moth Plutella xylostella in commercial Brassica crops. However, incorrect insecticide use can cause biological and ecological disturbances in agroecosystems. Cycloneda sanguinea is a generalist voracious predator and is distributed widely in cultivated and noncultivated ecosystems. This study investigated the efficiency of four insecticides for the control of P. xylostella and the lethal and sublethal effects of these insecticides on C. sanguinea.Spinosad (92% mortality) and chlorfenapyr (76% mortality) were highly toxic to P. xylostela. However, chlorantraniliprole (10% mortality) and methomyl (no mortality) were ineffective against this pest. Chlorantraniliprole was the only insecticide that was highly toxic to C. sanguinea by contact (90% mortality), however, it was nontoxic following the ingestion of chlorantraniliprole-contaminated aphids. Interestingly, ingestion of prey contaminated with methomyl and chlorfenapyr was highly toxic (100% mortality) to C. sanguinea. Spinosad was nontoxic to C. sanguinea via exposure to contaminated surfaces and following ingestion of contaminated prey. However, direct contact of the insects with both methomyl and spinosad significantly affected C. sanguinea flight activity (vertical flight and free-fall flight), whereas chlorfenapyr impacted vertical flight only.These findings showed that chlorantraniliprole was not only ineffective for the control of P. xylostela, but was also highly toxic to C. sanguinea. The results indicated that spinosad was efficient against P. xylostela and was of low toxicity to C. sanguinea; however, the deleterious effects of this insecticide on flight behavior could result in reduced predatory efficiency. © 2022 Society of Chemical Industry.

In the literature, no studies investigated which portion of the plagiotropic branches should be removed by pruning conilon coffee stem cuttings, as well as the effect of the remaining length of these branches on rhizogenesis, growth, and physiology of clonal seedlings. Thus, this work aimed to evaluate the remaining length of plagiotropic branches of conilon coffee stem cuttings on the growth and physiology of conilon coffee clonal seedlings. The experiment was conducted in the Fazenda Experimental de Marilândia, ES, Brazil, under a completely randomized design with five treatments and fifteen repetitions. The treatments referred to the length of plagiotropic branches (0.5, 1.0, 1.5, 2.0, and 2.5 cm from the point of insertion with the stem). After 120 days of cultivation, vegetative growth and physiological aspects of the seedlings were evaluated. The remaining plagiotropic branches between 1.5 and 2.0 cm long provide the best vegetative growth and physiological response of the conilon coffee seedlings. The lengths that provide the worst response, both in terms of growth and physiological aspects, were 0.5 and 2.5 cm. Made available in DSpace on 2022-03-11T15:01:40Z (GMT). No. of bitstreams: 1 influence-of-the-cut-length.pdf: 900995 bytes, checksum: 608e06ac3c0f6a653308dfd490e851a2 (MD5) Previous issue date: 2021

Experimental study conducted to feature the visual symptoms of macronutrient and boron deficiency and to assess the effect of nutrient omission on C. citratus growth. The study followed a completel...