Resumo Asparagus umbellatus é uma das plantas de folhagem de corte mais populares e amplamente utilizadas em decoração e buquês. No entanto, existe falta de informações sobre o manuseio pós-colheita do aspargo. Portanto, neste estudo, dois reguladores de crescimento ácido giberélico (GA) e ácido salicílico (SA) nas concentrações de 0, 100, 200 e 400 μM foram aplicados em duas etapas, pré e pós-colheita, separadamente e em combinação. Foram analizados os teores de clorofila, vazamento de eletrólitos, absorção de solução, população microbiana, teor relativo de água (%), teor de malondialdeído, catalase, superóxido dismutase e atividade de peroxidase juntamente com a vida de vaso da planta. Os resultados mostraram que a aplicação de GA e SA levou ao prolongamento significativo da vida de vaso em relação ao controle. A diferença de vida do vaso entre o controle (9,34 dias) e o tratamento superior, ou seja, GA200+SA200 (14,07 dias) foi superior a 50%. Além disso, a aplicação foliar pré-colheita de GA e SA aumentou ligeiramente a vida de vaso em comparação com a aplicação em solução de vaso. A vida de vaso estendida no experimento por colheita foi obtida usando os tratamentos SA100+GA100 e SA200+GA200.

Abstract Asparagus umbellatus is one of the most popular cut foliage plants that widely used in decorations and bouquets. However, there was a lack of information concerning Asparagus postharvest handling. Therefore, in this study, two growth regulators gibberellic acid (GA) and salicylic acid (SA) on concentrations of 0, 100, 200, and 400 μM were applied in two stages viz., pre and postharvest, separately and in combination. Experimental traits including; chlorophyll content, electrolyte leakage, solution uptake, microbial population, relative water content (%), malondialdehyde content, catalase, superoxide dismutase, and peroxidase activity along with plant vase life were evaluated. The results showed that the application of GA and SA lead to significantly extension of the vase life compared to the control. Vase life difference between control (9.34 days) and the superior treatment i.e. GA200+SA200 (14.07 days) was more than 50%. Also, the pre-harvest foliar application of GA and SA increased the vase life slightly compared to the application in vase solution. The extended vase life in the per-harvest experiment was obtained using SA100+GA100 and SA200+GA200 treatments.

Resumo A tulipa (Tulipa sp.) é uma espécie ornamental bulbosa com alta relevância econômica e grande área cultivada. A aspersão de álcool é estimada como uma estratégia válida para aumentar a produtividade de plantas em sistemas sustentáveis de agricultura. Este estudo objetivou investigar o efeito da aplicação de diferentes proporções de etanol e methanol nas características de tulipas utilizando um esquema factorial baseado em um design de blocos completamente aleatório, com dois fatores incluindo etanol em quatro níveis (0, 10, 20 e 30 vol%) e metanol em quatro níveis (0, 10, 20 e 30 vol%). As características avaliadas incluíram antocianinas, carotenoids, clorofila a e b, clorofila total, índice Brix das folhas e hastes, comprimento e largura das folhas, área foliar, peso fresco e seco dos bulbos, número de folhas e comprimento da haste floral. A análise de variância mostrou que efeitos significativos simples e de interação entre os diferentes tratamentos na maioria das características avaliadas. O maior valor de antocianina (3.92 mg 100 g-1 DM), comprimento foliar (25.83 cm), área foliar (258.6 cm2), e peso fresco de bulbo (25.81 g) foram obtidos em plantas tratadas com 30% de etanol, e o maior valor de antocianina (3.45 mg 100 g-1 DM) e índice Brix foliar (10.15%) foi relacionado com a aplicação de 30% de metanol. Conclui-se a partir dos resultados que methanol e etanol podem ser usados como reguladores do crescimento de plantas.

Abstract Tulip (Tulipa sp.) is of the highest economic importance and cultivated area among all bulbous ornamental species. The spray of alcohol is regarded as a proper strategy to improve plant yields in sustainable agriculture systems. This study aimed to investigate the effect of different rates of ethanol and methanol on the traits of the tulip in a factorial experiment based on a Randomized Complete Block Design with two factors including ethanol at four levels (0, 10, 20, and 30 vol%) and methanol at four levels (0, 10, 20, and 30 vol%). The estimated traits included anthocyanin, carotenoid, chlorophyll a and b, total chlorophyll, stem and leaf Brix index, leaf length and width, leaf area, total and bulb fresh and dry weight, leaf number, and flowering stalk length. Analysis of variance showed that the simple and interactive effects of different treatments were statistically significant on most estimated traits. The highest anthocyanin content (3.92 mg 100 g-1 DM), leaf length (25.83 cm), leaf area (258.6 cm2), and bulb fresh weight (25.81 g) were obtained from the plants treated with 30% ethanol, and the highest anthocyanin content (3.45 mg 100 g-1 DM) and leaf Brix index (10.15%) were related to 30% methanol. It can be concluded from the results that methanol and ethanol can be used as plant growth regulators.

Resumo Phalaenopsis amabilis Blume var. grandiflora Bateman é economicamente importante como flor cortada e em vaso. A poliploidia é considerada ferramenta valiosa no melhoramento e evolução das plantas ornamentais. Corpos semelhantes a protocórmio (PLBs) de P. amabilis foram cultivados em meio Murashige e Skoog contendo 0,20 mg L-1 de IBA junto com 2,00 mg L-1 KIN e 1,00 g L-1 de carvão ativado e cultivados por um período de cinco meses. Plântulas totalmente desenvolvidas de PLBs cultivadas in vitro foram imersas em um reator de bolha preenchido com solução de Hoagland meia-força contendo o agente antimitótico colchicina (0,05%, 0,10% e 0,15% p v-1) por 72 h com algumas gotas (1 mL de 0,1%) de octilfenoxipolietoxietanol ou Nonidet (P-40) como um surfactante. As plântulas foram aeradas para prevenir a hipóxia. As plântulas tratadas e não tratadas com colchicina foram transferidas para vasos por um período de 60 dias. A tetraploidia foi induzida com sucesso pela colchicina 0,15%. Os níveis de poliploidia foram detectados primeiramente por citometria de fluxo e depois confirmados por observações citológicas e morfológicas. O número de cromossomos era 2n = 2x = 38 em diploides e 2n = 4x = 76 em tetraploide. A incubação de mudas em meio líquido contendo 0,15% de colchicina induziu o máximo de tetraplóides recuperados com frequência mínima de sobrevivência (50%). As plantas tetraplóides eram mais compactas e exibiam folhas arredondadas e grossas com coloração verde mais escura que as diplóides. O tamanho dos estômatos nos tetraploides foi maior com menos densidade do que nos diploides. O número de cloroplastos nas células-guarda dos tetraplóides era cerca de duas vezes mais do que no controle. Esses resultados indicam que a indução de tetraplóides é uma ferramenta confiável e poderosa para a geração de novos fenótipos com valor ornamental e hortícola para melhoramento genético. Os tetraplóides produzidos no presente estudo têm potencial no comércio ornamental e floricultura.

Abstract Phalaenopsis amabilis Blume var. grandiflora Bateman is economically important as cut and pot flower. Polyploidy is considered as a valuable tool in improvement and evolution of ornamental plants. Protocorm-like bodies (PLBs) of P. amabilis were cultured on Murashige and Skoog medium containing 0.20 mg L-1 IBA together with 2.00 mg L-1 KIN and 1.00 g L-1 activated charcoal and grown for a period of five months. Fully-developed plantlets from in vitro grown PLBs were immersed in a bubble reactor filled with half-strength Hoagland solution containing the antimitotic agent colchicine (0.05%, 0.10% and 0.15%, w/v) for 72 h with a few drops (1 mL of 0.1%) of octylphenoxypolyethoxyethanol or Nonidet (P-40) as a surfactant. Plantlets were aerated to prevent hypoxia. Colchicine-treated and untreated plantlets were transferred to pots for a period of 60 days. Tetraploidy was successfully induced by 0.15% colchicine. Polyploidy levels were firstly detected using flow cytometry and then confirmed by cytological and morphological observations. The chromosome number was 2n = 2x = 38 in diploids and 2n = 4x = 76 in tetraploid. Incubation of plantlets in liquid medium containing 0.15% colchicine induced the maximum recovered tetraploids with minimum frequency of survival (50%). The tetraploid plants were more compact and exhibited round and thick leaves with darker green color than diploids. Stomata size in tetraploids were larger with less density than diploids. Chloroplast number in guard cells of tetraploids was about two times more than that of control. These results indicate that induction of tetraploids are a reliable and powerful tool for generation of novel phenotypes with ornamental and horticultural value for genetic improvement and breeding. Produced tetraploids in current study have potential in the ornamental/floriculture trade.

RESUMEN La salinidad es uno de los factores limitantes más importantes en el crecimiento de las plantas. También es una limitación predominante que afecta el crecimiento y la calidad del césped. Las hormonas vegetales desempeñan un papel importante en la capacidad de las plantas para adaptarse al estrés ambiental. Por lo tanto, se estudió el impacto de dos reguladores del crecimiento de las plantas (PGR), es decir, el ácido salicílico (SA) y la progesterona (P4), sobre las características biológicas de Poa pratensis en condiciones salinas en un experimento de invernadero. Los tratamientos experimentales estaban compuestos por salinidad en cuatro niveles (0, 2, 4 y 6 dS m-1) y seis niveles de PGRs (control, 1 mg L-1 P4,10 mg L-1 P4, 1 mM SA, 3 mM SA y 1 mg L-1 P4 + 1 mM SA). Los resultados mostraron que el porcentaje de disparo de las hojas se incrementó con el exceso de salinidad, pero el uso de SA y P4 alivió los efectos del estrés por salinidad y redujo el disparo de las hojas bajo salinidad. La salinidad de 6 dS m-1 y 3 mM de SA provocó la máxima fuga de electrolitos. El mayor contenido relativo de agua se observó en el tratamiento de 4 dS m-1 de salinidad y 1 mM de SA. La mayor glicina betaína se relacionó con 6 dS m-1 de NaCl y sin aplicación de hormonas. La salinidad aumentó la proteína total y la catalasa, y el uso simultáneo de P4 y SA mostró el mayor contenido de proteína total y catalasa, mientras que las plantas control mostraron los más bajos. La aplicación de estrés por salinidad redujo el contenido de clorofila, pero la SA y el P4 lo aumentaron. La aplicación de los dos reguladores de crecimiento mejoró el contenido de carotenoides bajo estrés por salinidad. En general, los resultados mostraron que la aplicación de SA y P4 mejoró la tolerancia a la salinidad y aumentó los pigmentos y las actividades de las enzimas antioxidantes.

ABSTRACT Salinity is one of the most important limiting factors in plant growth. It is also a predominant constraint that impairs grass growth and quality. Plant hormones play important roles in the capability of plants to adapt to environmental stresses. Hence, the impact of two plant growth regulators (PGRs) i.e. salicylic acid (SA) and progesterone (P4) was studied on biological characteristics of Poa pratensis in saline conditions in a greenhouse experiment. The experimental treatments were composed of salinity at four levels (0, 2, 4, and 6 dS m-1) and six levels of PGRs (control, 1 mg L-1 P4,10 mg L-1 P4, 1 mM SA, 3 mM SA, and 1 mg L-1 P4 + 1 mM SA). The results showed that leaf firing percentage was increased with the excess in salinity, but the use of SA and P4 eased the effects of salinity stress and reduced leaf firing under salinity. 6 dS m-1 and 3 mM SA salinity caused to the maximum electrolyte leakage. The highest relative water content was observed in 4 dS m-1 salinity and 1 mM SA treatment. The highest glycine betaine was related to 6 dS m-1 NaCl and no hormone application. Salinity increased total protein and catalase, and the simultaneous use of P4 and SA exhibited the highest total protein and catalase content, whilst the control plants showed the lowest ones. The application of salinity stress reduced chlorophyll content, but SA and P4 increased it. The application of the two growth regulators improved carotenoid content under salinity stress. Overall, the results showed that the application of SA and P4 improved salinity tolerance and increased pigments and antioxidant enzyme activities.

Resumo Impatiens hawkeri está entre as três principais plantas para forragem do mundo. Não existe um protocolo eficiente para a micropropagação rápida de Impatiens hawkeri cv. Sweeties Blue Star. Nódulos individuais germinados em meio Murashige e Skoog (MS) suplementado com ácido 1-naftalenoacético (NAA; 0,00, 0,10 e 0,50 mg l- 1), 6-benziladenina (BA; 0,00, 0,10, 0,50 e 1,00 mg l - 1) e cinetina (KIN; 0,00, 0,10, 0,50 e 1,00mg l-1). O comprimento dos brotos foi maior no meio contendo 0,10 mg l-1 de ANA e controle. O maior número de brotações (14,06 e 14,00 por explante) ocorreu em meio suplementado com 1,00 mg l-1 BA, 0,50 mg l-1 NAA e 1,00 mg l-1 BA, 0,10 mg l-1 NAA, respectivamente. O 0,10 mg l-1 de ANA em conjunto com 1,00 mg l-1 de BA foi considerado superior para a produção de folhas (57,13). O comprimento máximo da raiz (33,80 mm) e o número de raízes (29,13) foram obtidos em meio suplementado com 0,10 mg l-1 de ANA sem BA e KIN. As mudas foram transplantadas para vasos com perlita e turfa (na proporção de 1: 1) e transferidas para casa de vegetação para aclimatação. As mudas regeneradas eram morfologicamente idênticas às plantas-mãe. Na transferência ex vitro, 100% das plantas sobreviveram.

Abstract Impatiens hawkeri is among the three important bedding plants in the world. There is no efficient protocol for fast micropropagation of Impatiens hawkeri cv. Sweeties Blue Star. Single nodes were germinated on Murashige and Skoog (MS) medium supplemented with 1-naphthaleneacetic acid (NAA; 0.00, 0.10 and 0.50 mg l-1), 6-benzyladenine (BA; 0.00, 0.10, 0.50 and 1.00 mg l-1) and kinetin (KIN; 0.00, 0.10, 0.50 and 1.00 mg l-1). The shoot length was highest in medium containing 0.10 mg l-1 NAA and control. The largest number of shoots (14.06 and 14.00 per explant) was produced in media supplemented with 1.00 mg l-1 BA, 0.50 mg l-1 NAA and 1.00 mg l-1 BA, 0.10 mg l-1 NAA, respectively. The 0.10 mg l-1 NAA along with 1.00 mg l-1 BA was found to be superior for production of leaf (57.13). Maximum root length (33.80 mm) and root number (29.13) were obtained on medium supplemented with 0.10 mg l-1 NAA without BA and KIN. Plantlets were transplanted to pots filled with perlite and peat moss (in ratio of 1:1) and transferred to the greenhouse for acclimatization. Regenerated plantlets were morphologically identical with mother plants. Upon ex vitro transfer, 100% of plants survived.

Abstract The effect of salicylic acid (SA) and progesterone (P4) on physiological and biochemical parameters of Kentucky bluegrass under salinity stress was assessed. A factorial experiment was established based on a randomized complete block design with four replications, under greenhouse conditions. The experimental treatments included four levels of salinity (0, 2, 4 and 6 dS·m-1) and two plant growth regulators (P4 and SA) at six levels including the control (1 and 10 mg·L-1 P4, 1 and 3 mM SA, and 1 mg·L-1 P4 + 1 mM SA). The increase in salinity impaired the quality of grass, but SA and P4 application alleviated the impacts of salinity and ameliorated the quality of grasses under salinity. The highest electrolyte leakage was observed under 6 dS.m-1 salinity and 3 mM SA. The application of SA and P4 improved the carotenoid content in bluegrass subjected to saline stress compared to plants not treated with growth regulators. The highest total chlorophyll content was obtained from 2 dS·m-1 salinity and 10 mg·L-1 P4. Leaf proline content was increased with salinity level. However, slight differences existed between different levels of growth regulators. The SA and P4 increased proline content. Salinity increased the concentration of malondialdehyde (MDA) in the grass from 12 to 50 %, and growth regulators helped to reduce this concentration. Also, an increase in peroxidase activity with 6 dS·m-1 salinity was observed when SA and P4 were applied simultaneously. Overall, it was observed that SA and P4 increased salinity tolerance through enhancing grass quality, chlorophyll, and carotenoid content and scavenging free oxygen radicals through influencing antioxidant enzymes.

Resumen El objetivo del presente estudio fue evaluar el efecto del ácido salicílico (AS) y la progesterona (P4) sobre los parámetros fisiológicos y bioquímicos en pasto azul de Kentucky sometido a estrés por salinidad. Se estableció un experimento factorial basado en un diseño de bloques completos al azar con cuatro repeticiones, en condiciones de invernadero. Los tratamientos experimentales incluyeron cuatro niveles de salinidad (0, 2, 4 y 6 dS·m-1) y dos reguladores de crecimiento vegetal (P4 y AS) en seis niveles, incluyendo el control (1 y 10 mg·L-1 de P4, 1 y 3 mM de AS, y 1 mg·L-1 de P4 + 1 mM de AS). El aumento de la salinidad dañó la calidad del pasto, pero la aplicación de AS y P4 alivió los impactos de la salinidad y mejoró la calidad del pasto. La mayor pérdida de electrolitos se observó con 6 dS·m-1 de salinidad y 3 mM de AS. La aplicación de AS y P4 mejoró el contenido de carotenoides en pasto azul sometido a estrés salino en comparación con las plantas no tratadas con reguladores de crecimiento. El mayor contenido total de clorofila se obtuvo con 2 dS·m-1 de salinidad y 10 mg·L-1 de P4. El contenido foliar de prolina se incrementó con el nivel de salinidad; sin embargo, se presentaron pequeñas diferencias entre los distintos niveles de los reguladores de crecimiento. El AS y la P4 aumentaron el contenido de prolina. La salinidad incrementó la concentración de malondialdehido (MDA) en el pasto de un 12 a 50 %, y los reguladores de crecimiento ayudaron a reducir dicha concentración. También, se observó un aumento en la actividad de la peroxidasa con 6 dS·m-1 de salinidad cuando el AS y la P4 se aplicaron simultáneamente. En general, se observó que el AS y la P4 aumentaron la tolerancia a la salinidad al incrementar la calidad del pasto, la clorofila y el contenido de carotenoides, y al eliminar radicales libres de oxígeno, al influir en las enzimas antioxidantes.

Abstract The use of animal sex hormones in plants does not have a long history, but the presence of these hormones in plants has been proven. The aim of the research was to investigate the effects of gibberellic acid and progesterone on growth and development of Zinnia elegans flower in a factorial experiment based on a completely randomized design with three factors considering three replications. The first factor included application times (pre-sowing, four-leaf stage and two months after sowing), the second factor was progesterone rates (0, 5 and 10 mg·L-1) and three gibberellic acid rates (0, 100, and 200 mg·L-1). The measured traits were dry weight and fresh weight of aerial organ and root, number of nodes, number of flowers, number of buds, number of branches and leaves, the distance from the crown to the first leaf, the distance from the crown to the first branch, plant height, chlorophyll a, b and total chlorophyll and leaf area. Results showed that the highest fresh weight of aerial organ and root, maximum number of nodes, flower number, bud number, branch number, the highest plant height and the highest content of chlorophyll a occurred two months after planting. Overall, 10 mg·L-1 progesterone had the best effects on the traits. The maximum leaf area was obtained by applying 5 mg·L-1 two months after sowing.

Resumen El uso de hormonas sexuales de animales en plantas no tiene una larga trayectoria, pero se ha demostrado la presencia de estas hormonas en plantas. El objetivo de este estudio fue evaluar los efectos del ácido giberélico y la progesterona en el crecimiento y desarrollo de flores de Zinnia elegans. Se estableció un experimento factorial con base en un diseño completamente al azar con tres factores y tres repeticiones. El primer factor fue el momento de aplicación (antes de la siembra, etapa de cuatro hojas y dos meses después de la siembra), y el segundo y tercer factor incluyeron la dosis de progesterona (0, 5 y 10 mg·L-1) y ácido giberélico (0, 100 y 200 mg·L-1), respectivamente. Las variables evaluadas fueron peso seco y peso fresco del órgano aéreo y la raíz, número de nudos, flores, brotes, ramas y hojas, distancia de la copa a la primera hoja, distancia de la copa a la primera rama, altura de la planta, clorofila a, b y total, y área foliar. Los resultados mostraron que el mayor peso fresco del órgano aéreo y la raíz, el número máximo de nudos, el número de flores, el número de brotes, el número de ramas, la mayor altura de la planta y el mayor contenido de clorofila a se obtuvieron dos meses después de la siembra. En general, 10 mg·L-1 de progesterona presentó los mejores efectos en las características evaluadas. El área foliar máxima se obtuvo al aplicar 5 mg·L-1 de progesterona dos meses después de la siembra.