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ABSTRACT:The objective of this study was to determine the variability of the head loss as a function of the emitter geometry as well as to develop a relation between local head loss caused by the emitter insertion and geometric characteristics of the emitter pipe, using index of obstruction for dripper pipes with non-coaxial emitters. For this, an experimental bench was developed to control the system and obtain the variables pertinent to the study. From the value of the total head loss in the emitter pipe and the value obtained with calculation of the distributed head loss in the pipe, the difference of these values was local head loss caused by the insertion of the emitter. Total head loss in the emitter pipe and local head loss on the emitter presented a potential relation with flow rate. The kinetic head coefficient (k), for each emitter studied, was obtained from the local head loss on the emitter and the kinetic head. A model for estimating the k coefficient based on the obstruction index was then generated.

In vitro flowering is a technique used in genetic improvement that accelerates generations and favors the faster fixation of new traits of agronomic and market interest. The study aimed to establish a protocol for the in vitro flowering of Dendrobium nobile, through the combined temperature and of the growth regulator thidiazuron (TDZ) effects. Experiments was performed in a flask that was kept in a BOD incubator at 18, 21, or 24 °C or in a growth room at 26 °C. The TDZ concentrations were 0.0, 0.5, 1.0, and 2.0 mg L-1. The highest percentage of flowering shoots of 13.7% occurred at a concentration of 2 mg L-1 of TDZ grown at a temperature of 18 °C. Dendrobium nobile in vitro flowering was promoted in plants cultivated in ½ MS supplemented with 30 g L-1 sucrose, 5.5 g L-1 agar, 100 mL L-1 coconut water, pH 6.0, and 2.0 mg L-1 TDZ at a controlled temperature of 18 °C and a photoperiod of 16 h. The in vitro flowering induction protocol of the D. nobile species could be used or improved for future studies.

O aumento da urbanização tem alterado os serviços ecossistêmicos em áreas urbanas de todo o mundo. A cada ano, problemas de inundações são mais frequentes e a demanda por soluções de drenagem urbana de baixo impacto e que agreguem bem-estar as cidades é crescente. A fim de auxiliar os gestores de pequenas cidades no planejamento urbano, este trabalho teve como objetivo aplicar uma metodologia de cálculo simplificada capaz de prever o comportamento do escoamento superficial, após eventos de chuva. Para isso, foi estimado o hidrograma de projeto, através de simulações hidrológicas, de uma bacia de escoamento em bairro na cidade de Lavras (Minas Gerais/Brasil) considerando diferentes configurações de jardins de infiltração. Os resultados obtidos mostram que os jardins de infiltração propostos podem ocupar até 6,9% da área estudada, ou 42% das áreas de caixa de via. Esse aumento na área permeável resulta na redução de até 37% da precipitação efetiva e 41% da vazão de pico do hidrograma de projeto. Há um efeito no aumento do tempo de pico de 9,4% e a duração do escoamento superficial de 7,3%. Concluímos que a metodologia simplificada utilizada consegue demonstrar o impacto dos jardins de infiltração no escoamento superficial da água em uma bacia de escoamento. A presença dos jardins de infiltração amortiza o hidrograma gerado por um evento de precipitação, através da redução da precipitação efetiva. PALAVRAS-CHAVE: Áreas verdes. Jardim de chuva. Planejamento urbano.

Light quality is an important factor for the adequacy of plant production through plant tissue culture, as it directly interferes with morphogenesis and photosynthetic capacity of explants. The objective of this study was to analyze the impact of monochromatic lights such as light emitting diode (LED) on the in vitro development of Cattleya walkeriana G. and their effects on acclimatization. The plants were developed in vitro under the colors of green, blue, yellow, red, 2 red:1 blue, and white LED lights. For in vitro cultivation, Knudson medium was used, supplemented with 20 mg L-1 sucrose, 5.5 mg L-1 agar, 2% activated charcoal, 100 mL coconut water, and pH 6.0. For ex vitro cultivation, the plants were acclimatized in styrofoam trays containing sphagnum as a substrate. In general, the supplied light lengths impactedin vitro growth and acclimatization analyses. There was influence on the cuticle thickness of plants in vitro. Chlorophyll and carotenoid contents were not significant. We can conclude that light lengths formed by 2 red:1 blue, red and yellow LEDs can be indicated for better performance in the production of C. walkeriana. The 2 red:1 blue and red LEDs provide superior in vitro development than the others, with gains for the species in acclimatization. The yellow LED provided a possible in vitro hardening, which ensured the greatest success of the seedlings during acclimatization.