Thalia Schilisting

Objetivo: Avaliar o efeito de diferentes níveis de sombreamento no crescimento inicial de mudas de Ocotea porosa. Métodos: O experimento foi conduzido em delineamento inteiramente casualizado, com quatro tratamentos de sombreamento (controle a pleno sol, 30%, 50% e 70%). Aos 12 meses, avaliaram-se a altura total e o diâmetro do coleto das mudas, submetidos à análise de variância (ANOVA) e ao cálculo do tamanho de efeito (ômega ao quadrado). Resultados: Não houve diferença significativa entre os tratamentos no diâmetro do coleto (média geral de 3,6 mm) nem na altura das mudas (média geral de 21,5 cm), com tamanhos de efeito classificados como baixo e nulo, respectivamente. Conclusão: Mudas de Ocotea porosa toleram diferentes níveis de sombreamento na fase inicial de desenvolvimento, sem comprometimento do crescimento, atingindo dimensões adequadas para a expedição a campo. Recomendam-se estudos futuros com maior avaliação de variáveis morfológicas e fisiológicas complementares.

Objetivo: Avaliar o desenvolvimento de mudas de Ilex paraguariensis e de Acca sellowiana em diferentes substratos. Métodos: O experimento foi conduzido em delineamento inteiramente casualizado, com cinco tratamentos: um controle e quatro contendo diferentes proporções de rejeito alimentício de aves misturado à serragem. Foram avaliados as taxas de mortalidade, o número de folhas, a altura e outros parâmetros de crescimento. Resultados: para a erva-mate, os tratamentos com maiores proporções de rejeito promoveram melhor desenvolvimento das mudas, enquanto, para a goiaba-serrana, a menor proporção apresentou os melhores resultados, evidenciando respostas distintas entre as espécies quanto ao uso do resíduo como componente do substrato. Conclusão: O rejeito alimentício pode ser usado como componente de substratos para mudas, oferecendo uma alternativa sustentável aos resíduos agroindustriais. Sua eficiência varia com a espécie e a proporção usada.

Objetivo: Avaliar a variação biométrica de sementes e o desenvolvimento inicial de plântulas de Araucaria angustifolia provenientes de diferentes matrizes e localidades do Planalto Sul Catarinense. Métodos: O experimento foi conduzido em delineamento inteiramente casualizado, avaliando separadamente quatro locais de coleta e quatro matrizes por localidade. Foram avaliados o comprimento, a largura, a espessura, a massa, a germinação e o índice de velocidade de germinação das sementes, além da altura, do diâmetro do coleto e das massas secas da parte aérea e das raízes das plântulas. Resultados: As características biométricas das sementes diferiram entre matrizes, mas não entre localidades. A germinação foi influenciada pelas localidades e pelas matrizes, enquanto o índice de velocidade de germinação variou apenas entre localidades. O desenvolvimento inicial das plântulas apresentou diferenças significativas entre matrizes, sem efeito consistente das localidades. As análises de correlação evidenciaram associação forte apenas entre largura e espessura das sementes, enquanto as demais características biométricas apresentaram baixa associação com a germinação, o vigor e o crescimento inicial das plântulas. Conclusão: A biometria das sementes de A. angustifolia reflete principalmente a variabilidade entre matrizes, porém não constitui um indicador confiável do potencial germinativo ou do desempenho inicial das plântulas quando analisada isoladamente. Assim, a seleção de matrizes para conservação e produção de mudas deve considerar, além dos atributos biométricos, avaliações fisiológicas e de desempenho das progênies.

Objetivo: Avaliar a influência de doses de fertilizante de liberação controlada (FLC) e do uso de bokashi no crescimento inicial de mudas de Eugenia involucrata. Métodos: O experimento utilizou plântulas da espécie, transplantadas para tubetes de 180 cm3 contendo substrato comercial adicionado de cinco tratamentos da combinação entre FLC (0, 3 e 6 g L-1) e bokashi (0, 15 e 30%). Após 60 dias da instalação do experimento, avaliou-se a sobrevivência (%) das plântulas, bem como o incremento de altura (cm) e o diâmetro do coleto (mm). Resultados: Observou-se efeito significativo dos tratamentos apenas no incremento de altura. A sobrevivência média permaneceu em 91% e o diâmetro do coleto em 1,26 mm. Já para a altura, os tratamentos com adição de FLC apresentaram melhor desempenho, com ganhos de até 2 cm. Conclusão: Recomenda-se o uso de apenas 6 g L-1 de FLC para favorecer o desenvolvimento inicial de plântulas de Eugenia involucrata.

Background: Epicormic sprouting represents a promising strategy for vegetative rescue and propagation of mature trees; however, factors influencing sprout productivity and viability remain insufficiently understood for Ilex paraguariensis. This study evaluated the epicormic sprouting potential of detached branches according to disposition sense (horizontal and vertical) and branch diameter (thin and thick), as well as the adventitious rooting performance of cuttings derived from epicormic and canopy sprouts. Detached branches were maintained under controlled mini-tunnel conditions and assessed over a 120-day period for survival, sprouting percentage, number of sprouts and sprout length. Subsequently, cuttings from both material sources were evaluated for survival, callus formation, rooting and sprout development. Results: Disposition sense was the main factor influencing sprouting dynamics. Vertically disposed branches exhibited faster initial sprouting but reduced longevity, whereas horizontally disposed branches showed slower development combined with extended survival. Branch diameter had secondary effects, mainly influencing early sprouting responses. Epicormic cuttings presented lower survival compared to canopy-derived material; however, rooting percentages were statistically similar between sources. Conclusion: These findings demonstrate that detached branches constitute a viable ex situ source of epicormic sprouts, allowing flexible management strategies depending on production goals. Nevertheless, improvements in environmental conditions and propagule physiological status may be required to enhance survival in vegetative propagation. Overall, detached branches represent a promising alternative for the propagation and conservation of I. paraguariensis, supporting clonal propagation programs while minimizing damage to the selected trees.

Our objective was to evaluate the effect of a commercial organic fertilizer and substrate conditioners on the production of Eucalyptus benthamii seedlings. Two experiments were conducted with different doses of organic fertilizer (0, 5, 10, 15, 20, and 25 kg m⁻³) and levels of hydrogel (0 and 3 kg m⁻³) and biochar (0 and 30%). In each experiment, plots were divided into two subplots, with one subplot receiving topdressing with mineral fertilizers. At the end of each experimental period, quality, root morphology, and physiological characteristics of the seedlings were assessed. When only the organic fertilizer was applied with substrate conditioners, seedlings exhibited limited growth, averaging 5.02 cm in height and 0.81 mm in stem diameter. Topdressing fertilization combined with higher organic fertilizer doses (20–25 kg m⁻³) enhanced key traits, such as height (up to 24.15 cm) and stem diameter (up to 2.39 mm). Hydrogel and biochar often reduced seedling quality and root development. Some interactions between factors affected certain root variables, but physiological characteristics remained largely unaffected. Overall, even when combined with a substrate conditioner, the commercial organic fertilizer is insufficient to produce high-quality seedlings. Neither hydrogel nor biochar is recommended under our experimental conditions. However, the commercial organic fertilizer shows potential when used with mineral fertilizers and further should be conducted to explore this possibility.

Eucalyptus cultivation in Brazil benefits from techniques such as mini cutting; however, adverse climatic conditions in the southern region of the country limit seedling production. This study evaluated the effects of LED lighting (blue, red, combined, and natural) and cultivation environments (greenhouse with and without heating, and conventional nursery) on the propagation of Eucalyptus dunnii. The experiment, conducted in Otacílio Costa, SC, followed a two-factor (4 × 4) design with biweekly data collection from March to September 2024. Variables analyzed included sprout productivity, rooting performance, phytosanitary status (powdery mildew incidence), physiological parameters (photosynthetic rate, stomatal conductance, transpiration), and nutritional content. The results showed that LED lighting and cultivation environments did not affect the incidence of powdery mildew. Rooting was enhanced during winter in the heated mini-tunnel system. Sprout productivity was highest in the mini tunnel (~360 sprouts/m² under red light in winter), while heated environments led to a reduction in sprout production. Physiological variables such as photosynthetic rate and stomatal conductance were improved in the heated mini-tunnel, and transpiration responded to the interaction between light spectrum and environment. The evaluated factors did not cause significant changes in the nutritional profile of the mini stumps. It is concluded that the mini tunnel, particularly when heated during winter, enhances rooting and physiological responses, while red LED light increases sprout productivity. Supplemental LED lighting proved to be a strategic tool for overcoming seasonal limitations in Eucalyptus propagation.

When producing Ilex paraguariensis seedlings through vegetative propagation, selecting the correct populations and genotypes, and obtaining juvenile material, may be fundamental for its success. Therefore, this search aimed to test its vegetative propagation through cutting and rescue using detached branches of different populations in Santa Catarina state, Brazil. Thus, two experiments were installed in September 2019 in order to test: I) the cuttings of four populations belonging to the municipalities of Catanduvas (CT), Painel (PL), Três Barras (TB), and Urupema (UR), using ten randomly chosen genotypes from each, and; II) the epicormic sprouting of detached branches from these same populations. Both experiments were carried out in Lages, Santa Catarina. In February 2020, the cutting was evaluated according to the percentages of survival, callus, rooting, new sprouts, and original leaves permanence. The branches were evaluated every 30 days after storing, observing the percentages of sprouting branches, number of sprouts, and length of sprouts in centimeters. As for cutting, there was a low survival percentage in all populations (70%), characteristic of material of high maturity. Rooting was low for populations (<1.5%) and genotypes (<10%). Branches presented sprouts up to 60 days, with TB presenting the highest total number of sprouts (approximately 300) and the greatest average length (2.8 cm). In general, survival and rooting of cuttings were affected by both populations and genotypes, highlighting TB. A similar response was observed for the branches’ sprouting. New studies with more populations, further analyses of the branches’ characteristics, and better storage conditions are recommended.