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The objective of this work was to define an early selection strategy to identify Cabralea canjerana (Meliaceae) clones with high multiplication rate. A mini-garden of 109 clones of canjerana seedlings was established in a completely randomized design, in an acclimatized greenhouse. From seedlings, the mini-stumps and mini-cuttings were obtained. Mini-cuttings were collected at five different times, and the number of mini-cuttings per mini-stump, rooting percentage, and number of rooted mini-cuttings were quantified. The number of rooted mini-cuttings per mini-stump was the only trait that showed high correlation with the others. Five groups of clones based on the number of rooted mini-cuttings per mini-stump were separated using k-means clustering, and the genetic gain from selection and Pearson correlation were estimated. The selection of the two best groups in each evaluation period resulted in high genetic gains from selection for all evaluated traits. Early selection for the number of rooted mini-cuttings discarded 65% of the evaluated clones, which increases experimental precision in evaluations of traits associated with plantlet growth and quality. Early selection for the number of rooted mini-cuttings per mini-stump at different times allows the identification of Cabralea canjerana clones with high multiplication rate. Resumo: O objetivo deste trabalho foi definir uma estratégia de seleção precoce para identificar clones de Cabralea canjerana (Meliaceae) com alta taxa de multiplicação. Um minijardim com 109 clones de plântulas de canjerana foi estabelecido com um delineamento inteiramente casualizado em casa de vegetação climatizada. Das plântulas, foram obtidas as minicepas e as miniestacas. As miniestacas foram coletadas em cinco épocas, e foram quantificados o número total de miniestacas por minicepa, a percentagem de enraizamento e o número de miniestacas enraizadas. O número de miniestacas enraizadas por minicepa foi o único caráter que apresentou alta correlação com os demais. Foram estabelecidos cinco grupos de clones com base no número de miniestacas enraizadas por minicepas, pelo agrupamento das k-médias, e estimados o ganho genético de seleção e a correlação de Pearson. A seleção dos dois melhores grupos em cada época resultou em altos ganhos de seleção para os caracteres avaliados. A seleção precoce para o número de miniestacas enraizadas descartou 65% dos clones avaliados, o que aumenta a precisão experimental em avaliações de caracteres associados ao crescimento e à qualidade das mudas. A seleção precoce do número de miniestacas enraizadas por minicepas, em diferentes épocas, permite identificar clones de Cabralea canjerana com alta taxa de multiplicação.

Seedling production of canjerana (Cabralea canjerana (Vell.) Martius) has been limited by difficulty in germination, caused by recalcitrant behavior of their seeds. The objective of this study was to develop an efficient protocol for conservation and production of canjerana micropropagated plantlets. Seeds of canjerana were disinfected with 0, 2.5, 5.0, 7.5 and 10% of NaOCl solution, at immersion times of 10, 20 and 30 min to produce aseptic seedlings, which were cultivated on Murashige and Skoog (MS) and Woody Plant Medium (WPM) media. Nodal segments were cultivated in WPM medium supplemented with 0 and 2.5 µM of 6-benzylamine purine (BAP), kinetin (KIN) and thidiazuron (TDZ) or with 0, 1, 3, 6, 9 and 12 µM of BAP. Micro-cuttings were cultivated in MS and WPM media with 0 and 5.0 µM of indole-3-butyric acid (IBA) and naphthaleneacetic acid (NAA). The rooted micro-cuttings were acclimatized in a humid chamber in a greenhouse. The highest percentage of aseptic seedlings was produced with a solution of 7.5% of NaOCl and immersion times of 20 and 30 min. Adding BAP, KIN and TDZ or increasing concentrations of BAP to the WPM medium did not increase shoot number and length. Neither the base medium nor the auxin (IBA and NAA) had a significant effect on the survival of micro-cuttings after 60 days of cultivation, but the addition of 5.0 µM of NAA did increase the percentage of rooting and survival during the acclimatization. Both nodal segments and micro-stumps of canjerana have showed a low rate of multiplication. The addition of 5.0 µM of NAA to the basal medium increased the percentage of in vitro rooting and the percentage of survival during acclimatization of canjerana plantlets. Key words: In vitro propagation, in vitro multiplication, in vitro rooting, acclimatization, microclonal hedge.

Anais do 35º Seminário de Extensão Universitária da Região Sul - Área Temática: Educação Este trabalho se propõe a apresentar o Programa Institucional de Apoio ao Desenvolvimento e Integração da Faixa de Fronteira, o qual, através de edital anual elaborado pela Pró-Reitoria de Extensão, tem o objetivo de selecionar ações de extensão para serem desenvolvidas na Faixa de Fronteira da região de abrangência do Instituto Federal Farroupilha, através de programas, projetos, cursos e eventos. O Programa, com edital lançado nos anos de 2016 e 2017, já estimulou 18 ações, coordenadas por servidores e realizadas por esses juntamente com a participação de alunos extensionistas, bolsistas e voluntários. São ações bilaterais bem-sucedidas que promovem a intensificação dos laços entre o Brasil e os países limítrofes, em especial Uruguai e Argentina e contribuem para as condições locais de cidadania, integração e promoção do desenvolvimento, além da qualificação no processo de formação dos envolvidos

Canjerana (Cabralea canjerana (Vell.) Martius) is a tree species indigenous to Brazil that when grown and managed in plantation systems are of great ecological and economic importance. Due to the difficulty of producing seminal seedlings, we examine the possibility of vegetative propagation by evaluating the rooting potential of canjerana mini-cuttings with different concentrations of indolbutyric acid (IBA) and substrate combinations. Mini-cuttings were treated with 2000 mg/L of IBA and planted in commercial substrate; coarse sand; carbonized rice husks; and a combination of the two. Apical and nodal mini-cuttings were treated with 0, 1000, 2000 and 3000 mg/L of IBA and planted in a combination of commercial substrate, coarse sand and carbonized rice husks. A mini-clonal hedge was formed with three clones of canjerana to evaluate mini-stump productivity and mini-cutting rooting. The combination of commercial substrate, coarse sand and carbonized rice husks maximized mini-cuttings rooting. Nodal mini-cuttings had higher rooting capability than apical ones. The application of 3000 mg/L of IBA improved rooting differentiation and growth of canjerana mini-cuttings. Canjerana clones differ in rooting capability and survival rates in vegetative propagation systems, but the use of a mini-cutting propagation system is a feasible production technique for this important species. Key words: Vegetative propagation, miniclonal hedge, mini-cutting rooting, indolbutyric acid.

The aim of this research was to evaluate the feasibility of rescuing adult plants by cuttings from post-fire epicormic shoots. We evaluated the native tree species erva mate ( Ilex paraguariensis St. Hil.) and canjerana ( Cabralea canjerana Vell. Mart.), which present difficult seedling production and are economically and ecologically important. The plant material used for the preparation of cuttings consisted of shoots from bud differentiation of tissue from the stem collar of the trees. One-bud cuttings of erva mate were treated with 4000 or 8000mg L-1 of indolebutiric acid (IBA) and the checks were not treated with auxins. The cuttings were grown in three different substrates: carbonized rice husks, vermiculite and coarse sand. The experiment was a factorial with a completely random design and five replicates of five cuttings. One-bud cuttings from the basal, intermediate and apical parts of canjerna shoots were treated with 0 or 6000mg L-1 of IBA and planted in commercial substrate and coarse sand (3:2 v/v). The experiment was a factorial with a completely random design and ten replicates of three cuttings. Cuttings from post-fire epicormic shoots can be used for rescuing erva mate and canjerana adult plants. Erva mate cuttings treated with 8000mgL-1 IBA have increased rooting when grown in coarse sand. Canjerana cuttings from the basal part of epicormic shoots have greater survival and rooting than those from intermediate and apical parts. RESUMO: O objetivo deste trabalho foi avaliar a possibilidade de resgatar árvores adultas por estaquia de brotos epicórmicos de rebrota pós-fogo. Foram estudadas a erva-mate ( Ilex paraguariensis St. Hil.) e a canjerana ( Cabralea canjerana Vell. Mart.), que são espécies nativas de difícil propagação por sementes e de relevante importância econômica e ecológica. O material vegetativo utilizado para o preparo das estacas foi constituído de brotos, provenientes da rebrota da diferenciação dos tecidos de gemas do colo de árvores matrizes com, aproximadamente, 20 anos de idade. Para a erva-mate, estacas de gema única foram tratadas com 4000 e 8000mg L-1 de ácido indolbutírico (IBA), e as testemunhas que não receberam tratamento auxínico. As estacas foram cultivadas em três diferentes substratos: casca de arroz carbonizada, vermiculita e areia de granulometria grossa. O experimento foi um fatorial no delineamento inteiramente casualizado, com cinco repetições de cinco estacas. Para canjerana, estacas basais, medianas e apicais de gema única, foram ou não tratadas com 6000mg L-1 de IBA e cultivadas em substrato comercial e areia de granulometria grossa (3:2 v/v). O experimento foi um fatorial no delineamento inteiramente casualizado, com dez repetições de três estacas. A estaquia de rebrota pós-fogo pode ser utilizada para o resgate de árvores adultas de erva-mate e canjerana. Estacas de erva-mate tratadas com 8000mg L-1 de IBA enraízam melhor em areia grossa. Estacas de canjerana, obtidas da porção basal das brotações, apresentam maior sobrevivência e enraizamento do que as medianas e apicais.

RESUMO Determinou-se o efeito da cobertura com tela plástica preta para atenuação da densidade de fluxo da radiação solar incidente sobre o crescimento da alface, nas condições de verão de Santa Maria, RS. Foram utilizados quatro canteiros cultivados com alface, sendo três deles cobertos com túneis de tela plástica preta de 18%, 30% e 50% de atenuação da radiação solar, respectivamente. O estudo foi realizado em três períodos, I: de 30.11.90 a 17.01.91, II: de 06.02.91 a 25.03.91 e III: de 10.12.91 a 01.03.92. Foram utilizadas as cultivares Maravilha de Verão (períodos I e II) e Regina (período III), respectivamente. Determinou-se a cada 7 dias, nos três períodos, o número de folhas e a massa da matéria seca do caule e das folhas. No período III foi medido também o comprimento do caule. Os valores de massa da matéria seca das folhas e do caule e o número de folhas foram mais elevados sob os túneis do que na testemunha (sem tela). Os valores mais elevados dos parâmetros de crescimento medidos ocorreram no tratamento de 30% de atenuação da radiação solar incidente. SUMMARY The effect of reduction in incident solar radiation on the lettuce growth in the Subtropical Central Region of the Rio Grande do Sul State, Brazil, was evaluated during the summer. The study was carried out in the Experiment Field of the Crop Production Department of the Federal University of Santa Maria. Four 12.0m x 1.2m plots were used. Three were covered by tunnels of plastic screen with 18%, 30%, and 50% of solar radiation reduction and one was left uncovered as a control. The experiment was carried out during three periods: from 11.30.90 to 01.17.91 (period I), from 02.06.91 to 03.25.91 (period II), and from 12.10.91 to 03.01.92 (period III). Samples of lettuce plants were taken every seven days to evaluate stem and leaf dry matter, and leaf number throughout the three experimental periods. Stem length were measured only during period III. All growth parameters evaluated were higher inside the tunnels than outside. The treatment with 30% of solar radiation reduction showed the highest lettuce growth rate.

RESUMO Foram determinadas alterações micrometeorológicas causadas por tela plástica preta com 18, 30 e 50% de atenuação da radiação solar incidente, durante os meses de verão, em Santa Maria, RS. O experimento foi conduzido no Campo Experimental do Departamento de Fitotecnia da UFSM, onde foram cultivados quatro canteiros com alface, três deles cobertos com túneis de tela plástica. O estudo foi realizado em 3 períodos: de 30/11/90 a 17/01/91, de 06/02/91 a 25/03/91 e de 10/12/91 a 01/03/92. Mediu-se a radiação solar global, radiação solar na faixa de comprimento de onda do infravermelho e a luminosidade, temperatura diurna do solo, temperatura mínima e diurna do ar e umidade do solo e do ar. Os resultados mostraram que a temperatura do solo e do ar e a perda de água do solo são menores sob os túneis do que no exterior. As diferenças cresceram com o aumento da atenuação e a temperatura mínima do ar e a umidade relativa do ar são semelhantes no interior e exterior dos túneis e entre os túneis com diferentes percentagens de atenuação. SUMMARY Micrometeorological afterations caused by low tunnels of black plastic screen with 18, 30, and 50% of solar radiation reduction in central region of the Rio Grande do Sul state, Brazil, was investigated during the summer. The experiment was carried out in the Federal University of Santa Maria, where four plots were cultivated with lettuce. Three plots were covered by low tunnels of black plastic screen and one was left uncovered as a control. The study was conducted in 3 periods: 11/30/90 to 01/17/91, 02/06/91 to 03/25/91, and 12/10/91 to 03/01/92. Soil and air temperature, and soil water consumption decreased with solar radiation reduction. However, air minimum temperature and relative humidity were similar inside and outside, and aiso among different leveis of reduction caused by plastic screen.