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.

The knowledge of physiological and biochemical aspects occurring at the postharvest phase of flowers is critical to guide efficient conservation techniques for maintaining quality and longevity. Factors that cause deterioration of cut flowers after harvest are dehydration, low carbohydrate contents, the presence of microorganisms in vase solution or stem and late stage of development at harvest. Thus, the objective was to determine the effect of harvest stages of calla lily stems and storage solutions on water relations and contents of starch and sugars. Flower stems were harvested in the following opening stages of the spathe: early-stage (cartridge) and 1/3 open and were arranged in six storage solutions containing 1, 2, 4 and 6% glucose and the controls with water and solution with 5% sucrose. Results indicate that at early-stage and 1/3 open harvesting stages, the addition of glucose at concentrations of 4% and 6% stimulated flower opening. Calla lily flower stems maintained in water and in solution with 1% glucose had lower percentages of fresh weight loss and better maintenance of water balance, with a small reduction in the contents of starch and soluble sugars. The addition of sugars in the storage solution was efficient in opening early-harvested stems. Harvest the floral stems in initial stages allow the maintenance of the commercial quality for longer period, without pollen production. The use of water relations allowed the determination of the better sugar concentration for the conservation of open-harvest of floral stems.

The incidence of lepidopteran defoliants is one of the environmental factors that regulate the productivity of cultivated forests. The parasitoid Palmistichus elaeisis (Hymenoptera: Eulophidae) has significant importance for its efficiency in the parasitism of pupae of these Lepidoptera. The objective of this study was to evaluate the development and reproduction of P. elaeisis in different densities of pupae of Spodoptera frugiperda (Lepidoptera: Noctuidae) at different ages. Pupae of 24, 48, 72 and 96 hours were exposed at densities of 1:1, 4:1, 10:1, 19:1, 31:1 and 46:1 parasitoids/host, respectively. The parasitoids remained in contact with the pupae for 72 hours in 500 mL plastic pots, conditioned in an air-conditioned room, with temperature of 25 ± 2°C, relative humidity of 70 ± 10% and photoperiod of 12 hours. It was concluded that the density of 10:1 presented great results of parasitism, and further increase of density was not needed. Pupae of 24 and 48 hours had a higher percentage of emergence. Biological variables were affected neither by parasitoid densities nor by host age.

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.

The use of ornamental sunflower as a cut flower has been increasing due to the advent of new cultivars and the demand of the flowergrowing market for new products. However, there are few studies related to postharvest of this species. The objective of this research was to evaluate the water balance and durability of ‘Sunbright Supreme’ sunflower collected at three different harvest stages and submitted or not to a pulsing with sucrose. The flower stalks were collected fully open, at an intermediate opening stage and also closed; they were then standardized at 50 cm and stored in water or 4% sucrose solution during 24 hours. After this period, stalks were maintained in sealed bottles containing 500 mL of water. Fresh matter, water consumption, flower opening, complete durability and visual quality of stems were evaluated every three days, considering a rating scale of color, turgescence and stalk bending. Rates of absorption and transpiration were calculated considering the fresh matter and variation in water volume. There was an increase in fresh matter and high water consumption in inflorescences until the seventh day; after this period, there was a reduction in weight and increased transpiration rates. Stems collected closed, closed with pulsing and at an intermediate stage treated with pulsing were maintained in commercial quality about four days longer than the open harvested (with and without pulsing) and intermediate without pulsing. Sucrose pulsing leads to flower opening of stalks collected at all harvest stages. The positive water balance was observed until the seventh day and contributes to the maintenance of commercial quality in ornamental sunflower. The early harvest of ornamental sunflower ‘Sunbright Supreme’ is recommended, besides the application of 4% sucrose pulsing.

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The loss of commercial quality during storage and transportation of roses is one of the factors that reflect on production costs, leading producers to preventively apply harmful chemicals, mainly to hamper Botrytis cinerea development and reduce further losses. An alternative to increase flower longevity without contaminating the environment with harmful chemicals is the use of natural products, such as essential oils, which have fungistatic and insecticide properties, as well as low toxicity. The objective of this study was to evaluate the effect of essential oils on the vase life of Rosa cv. Avalanche: 12 treatments were tested, resulting from the combination of 5 types of essential oils plus the control in two cold storage periods (2 to 6 days) at 1 °C, 90-95% RH. The essential oils tested were eucalyptus, cinnamon, lemongrass and peppermint (1%), clove (0.1%), plus a control with distilled water. Application was made by spraying the flower buds. After storage at low temperatures, the flower stems were kept in a room (16 °C, 70% RH) during 10 days for evaluation. Flower stems stored for 2 days in a cold chamber showed better means for darkening, turgor and bent neck, as well as a lower weight loss by the stems. The application of lemongrass essential oil at 1% caused burns on the petals, compromising quality and pot life. The essential oils of peppermint and eucalyptus allowed flower quality maintenance until the 10th day of evaluation. It is possible to conclude that post-harvest spraying with peppermint or eucalyptus essential oil at 1%, combined with cold storage for 2 days, provided greater longevity and quality for cv. Avalanche roses. Keywords: Rosa sp., alternative control, cold storage, natural products, RESUMO Qualidade pós-colheita de rosas tratadas com óleos essenciaisA perda da qualidade comercial de rosas durante o armazenamento pós-colheita e transporte é um dos fatores que mais oneram o custo de produção e leva os produtores a realizar a aplicação preventiva de produtos químicos nocivos, principalmente para evitar o aparecimento de lesões do fungo Botrytis cinerea. Uma das alternativas para aumentar a durabilidade das flores de forma ecologicamente correta é a utilização de produtos naturais, como os óleos essenciais, que apresentam características fungistáticas e inseticidas, além de baixa toxicidade. O objetivo deste trabalho foi avaliar o efeito da aplicação em pós-colheita de diferentes óleos essenciais na durabilidade de hastes de Rosa cv. Avalanche em 2 períodos de armazenamento em câmara fria. Foram testados 12 tratamentos resultantes da combinação de 5 tipos de óleos essenciais mais a testemunha associados à dois períodos de armazenamento refrigerado, 2 e 6 dias, sob 1 ºC e 90-95% UR. Foram testados óleos essenciais de: eucalipto, canela, capimlimão e hortelã-pimenta (a 1%), cravo-da-índia (a 0,1%), e a testemunha, com água destilada. A aplicação foi feita por meio da pulverização nos botões florais. Após o armazenamento refrigerado, as hastes florais foram mantidas em uma sala ...

Papaya is a tropical fruit of great importance in the international and national market. For crop success, the use of quality seedlings is of paramount importance and substrates formulated from organic sources may be a viable alternative. In this context, the objective of this study was to evaluate the initial development of papaya seedlings in different formulations and levels of organic substrates. A completely randomized design was used in a 4x4+1 factorial scheme, corresponding to four substrate formulations, containing decomposed buriti stem (CDB). The treatments included of the following: (CDB, ½ CDB + ½ poultry manure, ½ CDB + ½ cattle manure and ½ CDB + ½ gray with plant origin sourced from materials resulting from the burning of plant material (stem, branches); four proportion levels of the formulations of the substrates mixed to the soil (25; 50; 75 and 100%) and the additional control (100% soil). The following variables were measured: plant height, leaf area, number of leaves, shoot dry matter, root length and root dry matter at 42 days of seedling cultivation. The results showed that use of an ideal source of organic matter is feasible in the production of papaya seedlings. The substrate consisting of CBD + poultry manure had great potential to be used in the production of papaya seedlings.