The COVID-19 pandemic has brought drastic routine changes to the world’s population. Social isolation, one of the recommended practices to curb the spread of the disease, can lead to the development of several problems, such as depression, stress, apathy and loneliness. However, practices associated with the cultivation and contemplation of flowers and ornamental plants can be an option to aid in the care for the mental health of the population. It has been proven that hortitherapy helps in the treatment of mental illness, in the recovery of patients. Biophilia incorporated into architectural design and gardening, as a hobby and occupational therapy, can also be used to improve physical and mental health. Activities can be done indoors, outdoors or even virtual, with flowers and plants used as supporting instruments to make the population feel better, including the situation experienced by the period of seclusion.

Silicon (Si) has been reported to enhance plant resistance against biotic and abiotic stressors and also benefit plant growth. These effects are more pronounced in grass species, especially with soil-applied Si. This study investigated the effects of Si application on rice resistance to Spodoptera frugiperda development and plant vegetative growth. Effects of Si on rice were assessed via soil and foliar applications and compared with untreated plants (control). Si was soil-and foliar-applied as 1% silicic acid solution at a dosage equivalent to 1.4 t Si per ha. After application, leaf material was collected from Si-treated and untreated plants and placed in Petri dishes with individual S. frugiperda neonate larvae, where development was followed to adult emergence and biological parameters recorded. Vegetative growth parameters recorded in rice plants were the height, chlorophyll content, fresh and dry weights of shoots, and shoot Si content. No effects of Si application were observed on the durations of larval and pupal stages, larval and pupal survival, and sex ratio of S. frugiperda. Insects fed leaves from Si-treated plants exhibited lower leaf consumption, larval and pupal weights, longevity of males and females, number of eggs, and egg viability. The negative effects were correlated with higher rice Si content. Si application to rice increased plant height, chlorophyll content and dry weight. Our study demonstrates that foliarapplied Si is as efficient as soil-applied Si in negatively affecting S. frugiperda development and providing beneficial effects on rice plant growth. K E Y W O R D Sfall armyworm, integrated pest management, Oryza sativa L., plant resistance, silicic acid

The aim of this study was to evaluate the effects of silicon application and administration of the phytohormone gibberellic acid on resistance of the corn plants to the fall armyworm (FAW), Spodoptera frugiperda, and their vegetative characteristics. We evaluated larval and pupal duration, survival and biomass, and adult longevity, malformation and fecundity of S. frugiperda after feeding on plant matter treated with silicon and/or gibberellic acid. The feeding preference of FAW first-instar larvae, the total leaf area consumed by the insects, and the vegetative parameters of corn plants were also evaluated. No significant differences were observed in the measured parameters of larval and pupal stages of S. frugiperda in response to silicon or gibberellic acid. In adult stage insects, the number of eggs per female was significantly reduced in insects derived from larvae fed plants treated with silicon or gibberellic acid. In a non-preference test, 48 h after release, caterpillars preferred control untreated plants and consumed less matter from plants that had received hormonal treatment (gibberellic acid). Gibberellic acid also altered the vegetative characteristics of plants, by increasing their height, shoot fresh and dry mass, and silicon content. We conclude that gibberellic acid can alter the vegetative characteristics and silicon uptake of corn plants, leading to a reduction in their consumption by S. frugiperda larvae and a decrease in female insect oviposition.

Cut flowers are a well established product and require conservation techniques that help keep postharvest quality for marketing. In this context, the objective of this study was to evaluate different opening stages of calla lily (Zantedeschia aethiopica) cut stems and their influence on posthaverst. Calla lily stems were harvested in the morning, according to the following opening stages: closed spathe, semi-closed spathe (1/3 open), semi-open spathe (2/3 open) and fully open spathe. Once selected and standardized, stems were placed in a controlled room at 21 ± 2 °C and relative humidity of 75 ± 5%, for eight days. The evaluations were conducted daily, observing water pH, commercial quality analysis, width and length of the spathe, fresh weight of stem, water absorption and transpiration. The experimental design was completely randomized, with four treatments (opening stages), five replicates and two stems by plot. The model used was split plot in time, with harvest stages as plots, and evaluation days as subplots. Calla lily harvested at closed spathe and semi-closed spathe (1/3 open), showed spathe opening, although it did not achieve fully spathe expansion, had higher water uptake and hydration of flower stems, and increased water retention capacity by floral tissues until saturation, followed by a period of weight reduction caused by transpiration rates greater than absorption.

RESUMOA lagarta Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) é um inseto-praga polífago que causa danos consideráveis à cultura de arroz, com redução na produção e diminuição da qualidade de grãos. O objetivo deste trabalho foi avaliar a preferência alimentar e a sobrevivência dessas lagartas em plantas de arroz tratadas com silício (Si). Os tratamentos foram: 1) testemunha (sem aplicação de Si); 2) Si (drench) e 3) Si (foliar). Para avaliar a preferência em relação ao consumo foliar foi utilizado o DBC com três tratamentos e 20 repetições em teste de livre escolha. Foram liberadas 12 lagartas de 2 o ínstar no centro da placa de Petri e após 24, 48 e 72 h da infestação elas foram contabilizadas em cada tratamento sendo que após 72 h também se determinou a área foliar consumida. Para avaliação da mortalidade adotou-se o DIC com três tratamentos e 20 repetições, com liberação de 12 lagartas de 2 o ínstar por placa de Petri e após 24, 48 e 72 h da liberação foi determinada a sobrevivência. Pelos resultados obtidos conclui-se que a aplicação de silício em arroz afeta a preferência alimentar e a sobrevivência de lagartas de S. frugiperda.Palavras-chave: ácido silícico, insecta, lagarta das folhas, MIP, Oryza sativa L. Feeding non preference of Spodoptera frugiperda (Lepidoptera: Noctuidae) induced by silicon application in rice crop ABSTRACTThe caterpillar Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae) is a polyphagous insect pest that causes considerable damages in rice crop, such as reduction in production and in grain quality. We aimed in this work to assess the feeding preference as well as larvae survival in rice plants treated with silicon (Si). Treatments were compounded by different ways of Si application: 1) control (without Si), 2) Si (drench), and 3) Si (leaf). To assess preference regarding leaf consumption, a total of 3 treatments and 20 replicates were used in a randomized block design. Twelve second instar larvae were released in center of Petri dishes and at 24, 48, and 72 h of infestation larvae were assessed for each treatment, and at 72 h leaf area consumed was also determined. To assess mortality a total of 3 treatments and 20 replicates were used in a completely randomized design with a release of 12 second instar larvae per Petri dish. After 24, 48, and 72 h larval survival were determined. Through results obtained, it is concluded that silicon application affects feeding preference as well as S. frugiperda larval survival in rice crop.

Perfil y comportamiento de los usuarios de espacios verdes en pequeñas ciudades

No abstract

The use of chemicals in storage solutions has proved beneficial for the postharvest conservation of cut flowers. However, the effect of these solutions on the water relations of some species is still unknown. Therefore, the objective of the present investigation was to evaluate the water relations in calla lily flowers harvested at different stages and maintained under postharvest solutions with different chemicals. The flower stems were harvested in two stages of spathe opening: the early stage (cartridge) and the 1/3 flower opening stage. The flower stems were dipped in solutions with water (control), 100 mg L-1 sodium hypochlorite (NaClO), 100 mg L-1 aluminum sulfate [Al2(SO4)3], 200 mg L-1 8-hydroxyquinoline (8-HQ) and 10 mg L-1 silver nitrate (AgNO3). Over 9 days, the floral stems were kept in a room at 21 ± 2 °C and 75% ± 5% relative humidity and evaluated for changes in the pH of the solution and the water absorption, transpiration and commercial quality of the cut flowers. The addition of conservation substances to the storage solution induced spathe opening at both harvest stages and promoted water absorption by the stems, thus increasing the efficiency of flower hydration. The water balance maintenance was best for stems stored in water and storage solutions with Al2(SO4)3.