ABSTRACT Light is a determining factor in plant morphophysiology, as it influences the growth and development of agricultural crops. Thus, the objective was to investigate the effects of light sources on the growth and development of “biquinho” pepper cultivars. The experiment was performed in two stages (Exp1 and Exp2), evaluating two cultivars (BRS Moema; Airetama biquinho) in five light sources (white LEDs, red LEDs, blue LEDs, red/blue LEDs, and fluorescent lamps). In Exp1 the plants were kept in a controlled condition, with a completely randomized design, in a 2x5 factorial scheme (cultivars x light sources) until 76 days after emergence (DAE), in which growth variables and photosynthetic pigments were evaluated. In Exp2, the plants were removed from the above conditions and transplanted in pots, being kept in greenhouse for more 76 DAE. At 152 DAE, the same variables as Exp1 were evaluated, as well as gain of shoot fresh and dry mass, and gain of root fresh and dry mass. In both experiments, growth variables were affected by cultivar and the light sources, however, the behavior did not follow the same trend for all variables, indicating that the light quality influences the growth of the crops, and impacting during greenhouse conditions.

RESUMEN Los metabolitos secundarios son producidos por ciertas especies de plantas, y pueden influir en el desarrollo de algunas especies, debido a la acción de los efectos alelopáticos. Por lo tanto, el objetivo del trabajo fue evaluar el efecto alelopático del aceite esencial de Lippia alba en la germinación, emergencia y vigor de las plántulas de diferentes lotes de semillas de lechuga. El experimento se realizó en un diseño completamente al azar, en un esquema factorial 3x5, que consta de tres lotes de semillas del cultivar Grand Rapids® y cinco dosis de aceite esencial de L. alba (0; 0,25; 0,50; 0,75 y 1,00%) diluido en agua destilada y homogeneizado en Tween® 80. Se evaluó la germinación y el vigor de la semilla en el laboratorio (experimento I) y la emergencia en un ambiente protegido (experimento II). Los resultados obtenidos mostraron que hubo un efecto inhibitorio con una reducción significativa de la germinación, el vigor y la emergencia de la semilla cuando se añadió aceite esencial de L. alba a partir de concentraciones de 0.25%. El aceite esencial mostró potencial alelopático sobre diferentes lotes de semillas de lechuga, afectando la germinación, el vigor y la emergencia de las semillas.

ABSTRACT Secondary metabolites are produced by certain plant species and may influence the development of some species through the action of allelopathic effects. Thus, the objective of this study was to evaluate the allelopathic effect of Lippia alba essential oil on the germination, emergence and vigor of seedlings of different batches of lettuce seeds. This experiment was conducted in a completely randomized design with a 3x5 factorial scheme consisting of three batches of seeds of the cultivar Grand Rapids® and five doses of L. alba essential oil (0, 0.25, 0.50, 0.75 and 1.00%) diluted in distilled water and homogenized in Tween® 80. Seed germination and vigor, in the laboratory (experiment I), and emergence, in a protected environment (experiment II), were evaluated. The results demonstrated that there was an inhibitory effect with a significant reduction of germination, vigor and seed emergence when L. alba essential oil was added starting at concentrations of 0.25%. The essential oil showed allelopathic potential over different lettuce seed lots, affecting germination, vigor and seed emergence.

Resumo A fonte de luz na cultura de tecidos muitas vezes é um dos fatores pontuais para a adequação da produção de plantas, para isso, vêm se utilizando os diodos emissores de luz (LEDs) no intuito de aumentar o crescimento e desenvolvimento das plantas propagadas in vitro. O objetivo do trabalho foi avaliar a propagação in vitro de cultivares de Alpinia purpurata ‘Red Ginger’ e ‘Pink Ginger’ em duas diferentes fontes de luz (lâmpadas tubulares fluorescentes ou LED Branco). O experimento foi conduzido em delineamento inteiramente casualizado, esquema fatorial (2x2), totalizando quatro tratamentos com dez repetições, e a unidade experimental composta por um frasco contendo cinco explantes. Após 55 dias, foi possível observar que lâmpadas LED branco e a cultivar Red Ginger proporcionaram o maior número de brotos. Já para o número de folhas, a cultivar Red Ginger e lâmpadas LED branco proporcionaram resultados superiores. Para comprimento da parte aérea, a cultivar Red Ginger mantida sob lâmpadas fluorescentes foi superior, e a Pink Ginger apresentou superioridade quando cultivada sob luzes LED. Assim, mesmo com respostas diferenciadas entre genótipos, sugere-se o uso de lâmpadas LED branco na propagação in vitro das cultivares de Alpinia purpurata ‘Red Ginger’ e ‘Pink Ginger’.

Abstract The light source in tissue culture is often one of the punctual factors for the adequacy of plant production. For this, light emitting diodes (LEDs) have been used in order to increase the growth and development of the plants propagated in vitro. The objective was to evaluate the in vitro propagation of cultivars of Alpinia purpurata ‘Red Ginger’ and ‘Pink Ginger’ in two different light sources (fluorescent or LEDs tubes). The experiment was conducted in a completely randomized design, factorial scheme (2x2), totaling four treatments with ten replicates, and the experimental unit composed of one flask containing five explants. After 55 days, white LED and the ‘Red Ginger’ provided the highest number of shoots. For the number of leaves, the cultivar ‘Red Ginger’ and white LED lamps provided superior results. For shoot length (cm), the cultivar ‘Red Ginger’ kept under fluorescent lamps was superior, and ‘Pink Ginger’ presented superiority when cultivated under LED lights. Thus, even with differentiated responses among genotypes, the use of white LED lamps in the in vitro propagation of Alpinia purpurata ‘Red Ginger’ and ‘Pink Ginger’ cultivars is suggested.

RESUMO A produção e a qualidade dos morangos podem variar de acordo com a cultivar, a origem das mudas e o sistema de cultivo das plantas. O objetivo deste trabalho foi avaliar o efeito de diferentes substratos orgânicos e diferentes origens de mudas na produção de morangos e na qualidade dos frutos. O experimento foi conduzido em blocos ao acaso, em esquema fatorial 2x2x4, com duas cultivares (Albion e Camarosa, de dias neutros e dias curtos, respectivamente), duas origens de mudas (nacional-Brasileira e importada-Argentina) e quatro combinações de substratos: (Bagaço de cana-de-açúcar triturada [70%] + Composto orgânico [30%], Bagaço de cana-de-açúcar triturada [70%] + substrato comercial Carolina® [30%], casca de arroz queimada [70%] + composto orgânico [30% ] e cascas de arroz queimadas [70%] + substrato comercial Carolina® [30%]). A unidade experimental foi composta por oito plantas, com repetição em quatro blocos. Foram avaliados parâmetros de qualidade: acidez total titulável, sólidos solúveis totais, proporção de açúcar/acidez, firmeza, coloração da polpa (chroma, ângulo de matiz e L *, a * e b *), bem como parâmetros de produção: número total de frutas, produção total de frutas, massa média de frutas, produção de frutas não comerciais, produção comercial de frutas e produtividade total. A cultivar Camarosa de origem nacional, quando cultivada em cascas de arroz queimadas+composto orgânico, apresentou os melhores resultados de produção e qualidade dos frutos.

ABSTRACT The production and quality of strawberries may vary according to cultivar, transplant origin, and the system of plant cultivation. The objective was to evaluate the effect of different organic substrates and different transplant origins on strawberry production and fruit quality. The experiment was conducted in a randomized complete block design with a 2x2x4 factorial scheme using two cultivars (Albion and Camarosa) obtained from different origins (National-Brazilian and Imported-Argentine) and four combinations of substrates: (crushed sugarcane bagasse [70%] + organic compost [30%], crushed sugarcane bagasse [70%] + Carolina® commercial substrate [30%], burnt rice husks [70%] + organic compost [30%], and burnt rice husks [70%] + Carolina® commercial substrate [30%]). The experimental unit was composed of eight plants, with repetition in four blocks. The quality parameters of titrable total acidity, total soluble solids, ratio of sugar / acidity, firmness, and pulp coloration (chroma, hue angle, and L*, a* and b*) were evaluated, as were the production parameters of total number of fruits, total fruit production, average fruit mass, non-commercial fruit production, commercial fruit production and total productivity. The substrate influences the strawberry production variables. Fruit yield was highest in the Camarosa cultivar grown on the S3 substrate mixture. The cultivar, the transplant origin and the cultivation substrate influence fruit AT. SST and AT / SST are influenced only by cultivar and transplant origin. Chroma differs between plants with different transplant origins. Camarosa of National origin cultivated in burnt rice husks + organic compost presented the best production results and fruit quality.