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In this study, we hypothesized that Copaifera langsdorffii Desf. seedlings do not tolerate cultivation under water deficit, but shading could minimize stressor effects of water shortage and enable fast antioxidant responses, maintaining high photosynthetic rates and favoring stressed plant recovery. Therefore, we evaluated gas exchange and antioxidant activity of C. langsdorffii seedlings submitted to intermittent water deficit and different shading and their potential for metabolic recovery after re-irrigation. Seedlings were grown under 0, 30, and 70% shading and under continuous and intermittent irrigation. The plants were evaluated at the beginning of experiment, first and second zero photosynthesis, first and second recovery, and the end of experiment. Seedlings under intermittent irrigation and 0% shading could not recover their photosynthetic metabolism at the end of experiment, showing a marked decrease in rubisco carboxylation efficiency (A/Ci) and increase in antioxidant activity. Yet, seedlings grown under shading and intermittent irrigation could recover their photosynthetic metabolism, without permanent changes and/or damages to photosystem II efficiency, proving our hypothesis.

This study investigated the potential of shading to mitigate the stressful effects of different periods of flooding, favoring the recovery of seedlings in the post-flooding period. Copaifera langsd...

The Copaifera langsdorffii Desf. seedlings, popularly known as “copaiba” or diesel tree, present a natural occurrence in the riparian forests of the Brazilian Cerrado, however, not much is known about their capacity to recover from flooding, particularly when the focus is on their establishment and use in programs for the recovery of degraded areas near watercourses and subject to flooding. The objective of this study was to evaluate over time the recovery of the efficiency of the photosynthetic apparatus and the antioxidant activity of C. langsdorffii seedlings flooded during different periods. The pots with the seedlings were placed in a plastic tank and submerged with water, and were removed from the flood condition every 21 days (0, 21, 42, 63 and 84 days), and evaluated every 30 days (0, 30, 60, 90 and 120 days). The seedlings tolerated the flooding for up to 42 days, recovering after suspension of this condition. Seedlings flooded for 63 and 84 days showed lower recovery capacity after flooding, independently of the evaluation period. Under these conditions, lower efficiency of the photosynthetic apparatus, gas exchange, photo assimilate production and seedling quality were observed.

The aim of this study was to evaluate gas exchange, efficiency of the photosynthetic apparatus, and antioxidant activity in Copaifera langsdorffii Desf. The seedlings were cultivated under different conditions of water availability, in order to improve the utilization efficiency of available water resources. The seedlings were cultivated in four different water retention capacities (WRC- 25%, 50%, 75%, and 100%), and evaluated at four different time (T- 30, 60, 90, and 120 days). During the experimental period, seedlings presented the highest values for carboxylation efficiency of Rubisco (A/Ci), intrinsic water use efficiency (IWUE = A/gs), chlorophyll index, and stomatal opening, when grown in the substrate with 75% WRC, but the stomatal index (SI) was less the 25% WRC. The efficiency of photosystem II was not significantly altered by the treatments. Comparison between the extreme treatments in terms of water availability, represented by 25% and 100% WRC, represent stress conditions for the species. Water availability causes a high activity of antioxidant enzymes (superoxide dismutase, peroxidase, and catalase) in the plant.

The salinity is a limiting factor for germination to occur in most species being necessary studies that assess the interaction between plants and saline environment to which they are being associated. The present study had as aim to evaluate the germination and characteristics of vigor in Salvia splendens subjected to salinity. The seeds were exposed to different osmotic potentials, simulating salt stress caused by NaCl, KCl and CaCl2 at potentials of 0, -0.4, -0.8, -1.2, -1.6 and -2.0 MPa. In general, CaCl2 led to the best results for all variables, probably connected to the positive effect of Ca2+ in cell metabolism, allowing germination of 60.81% in the osmotic potential of -1.35 MPa.

The gladiolus is one of the most cut flowers produced and marketed in Brazil and worldwide. This work was conducted with the objective to evaluate the use of nitrogen and potassium fertilization associated with different sources and levels of phosphorus in the quality and durability in postharvest gladiolus (Gladiolus hortulanus L. cv. T704 ) cultured in oxisoil. It was used the experimental design randomized blocks and the treatments were arranged in sub-subplots. The plots were allocated the presence or absence of nitrogen and potassium fertilization (NK ), subplots sources of phosphorus (triple superphosphate, superphosphate and bone meal) and the sub-subplot the five P rates (0 , 75 , 150 , 225 and 300 kg ha-1) fertilizers studied . Plants were evaluated on the number of flower buds, number of colored buttons, and number of open flowers, leaf quality, and flower quality, quality of the stem, plant height, and length of floral spike, diameter and durability flower. Regardless of treatments and combinations studied, the leaves produced were classified as optimal. The combined action of the three factors studied (p < 0.05) was observed only on the diameter and durability of flowers. It was concluded that NK fertilization is crucial and that the dosages used in this study were sufficient to obtain class I quality gladiolus. The use of triple superphosphate is more efficient when the goal of flowers and durability, the superphosphate, when objective quality of the stems. Phosphorus levels between 150 and 160 kg ha-1 are sufficient to obtain durability and quality of the flowers and stems of this cultivar.

The Gladiolus is one of the most cultivated ornamental plants in Brazil, though there are few scientific information related to culture. The aim of this study was to evaluate the effect of nitrogen fertilization and corm size on growth and flowering of Gladiolus grandiflorus ‘San Remo’. The experiment was conducted in the area of Jardinocultura of Universidade Federal da Grande Dourados (UFGD) in Dourados - MS. The experimental design was completely randomized and the treatments in subplots, and the plot consisting of the diameters of the bulbs (large between 40 and 55 mm, medium between 20 and 40 mm and small than 10 mm) and the subplots of three nitrogen dose (30, 50 and 70 kg ha-1), with 10 repetitions. Evaluated the number of leaves, the leaves length, the beginning of flowering, the number of buttons per spike floral, the durability of the flower, the time of flowering and the number of cormilhos. The spikes produced were classified as Class III. Nitrogen fertilization was more efficient for the growth of corms medium and small size, with doses greater than 50 kg ha-1 provided better results. Corms large size and the aplication of 30 kg ha-1 nitrogen fertilization delayed the beginning of flowering. It is recommended to use medium-size corms and nitrogen fertilization of 50 kg ha-1 for the cultivation of Gladiolus gran­diflorus ‘San Remo’.

In clayey Oxisol from the Brazilian Cerrado, where there is high P fixation, the phosphorus fertilization is necessary to increase the growth and flowering of ornamental plants. Thus, the objective of this study was to analyze the development of Hemerocallis as affected by phosphorus application in clayey Oxisol (Typic Haplustox). The experiment was conducted at the Gardening area of University Federal of Grande Dourados (UFGD) in Dourados-MS, Brazil. The experimental design was a randomized block with four replications. The treatments consisted of four P2O5 rates (0, 250, 500, 1000 kg ha-1) using simple superphosphate as source. The experimental unit was composed of one Hemerocallis fulva ‘Flore Pleno’ plant, grown in a plastic pot (5 liters). Phosphorus fertilization increased linearly the concentration of phosphorus in the soil; the plant had maximum absorption (5.26 g kg-1) with the calculated dose of 727 kg ha-1 P2O5. H. fulva has a root system that develops best under high availability of P, however, for aerial part, the maximum of shoots fresh mass (451.1 g) was obtained with 427 kg ha-1 of P2O5. Number of flower buds, flower diameter and height flower stalks were higher in the presence of phosphorus. Em Latossolos argilosos do cerrado onde é alta a fixação de P, a adubação fosfatada torna-se necessária para garantir o crescimento e florescimento de plantas ornamentais. Assim, esse estudo objetivou analisar o desenvolvimento de hemerocale em função da adubação fosfatada em Latassolo Vermelho Distroférrico. O experimento foi conduzido na área de Jardinocultura da Universidade Federal da Grande Dourados (UFGD) em Dourados – MS. O delineamento experimental utilizado foi em blocos casualizados, com quatro repetições. Os tratamentos consistiram de quatro doses de P2O5 (0; 250; 500; 1000 kg ha-1) utilizando como fonte superfosfato simples. A unidade experimental foi composta por uma planta de Hemerocallis fulva ‘Flore Pleno’, cultivada em vaso plástico com capacidade para cinco litros. A adubação fosfatada aumentou linearmente os teores de fósforo no solo e a planta obteve a sua máxima absorção (5,26 g kg-1) com a dose calculada de 727 kg ha-1 de P2O5. A H. fulva possui sistema radicular que melhor se desenvolve sob alta disponibilidade de P, no entanto para parte aérea, o máximo de massa fresca da parte aérea (451,1 g) foi obtido com 427 kg ha-1 de P2O5. O número de botões florais, o diâmetro floral e altura da haste floral foram maiores na presença de fósforo.

A germinação em meio assimbiótico é um dos principais métodos de multiplicação de Orchidaceae. Entretanto, a viabilidade das sementes dessa família botânica é susceptível a fatores bióticos e abióticos que podem inviabilizar esse processo. Objetivou-se com este trabalho avaliar o efeito do período de armazenamento, de tratamento pré-germinativo e do tempo de cultivo sobre a porcentagem de germinação das sementes de Brassavola tuberculata e também verificar se o procedimento amostral do teste de tetrazólio é eficaz para predizer a porcentagem de germinação da espécie. O delineamento experimental utilizado foi o inteiramente casualizado e os tratamentos foram arranjados em esquema de parcelas sub-subdivididas, sendo alocados na parcela os tempos de armazenamento (até 360 dias), na sub-parcela os tratamentos pré-germinativos (embebição com água destilada ou com 4 mg L-1 de GA3) e na sub-subparcela os tempos de cultivo (15 ou 30 dias), com quatro repetições. O tratamento pré-germinativo com GA3 propicia aumento na porcentagem de germinação de B. tuberculata somente até os 130 dias de armazenamento. Sementes não submetidas a este fitorregulador podem ser armazenadas por 360 dias com porcentagem de germinação acima de 50%. B. tuberculata apresenta maior porcentagem de germinação aos 30 dias de cultivo tanto para sementes submetidas a tratamento pré-germinativo como não e, o teste de tetrazólio, efetuado de maneira amostral, pode ser utilizado apenas para indicação da viabilidade das sementes armazenadas.

The objective was to evaluate the effect of different doses of nitrogen and phosphorus on growth and development of Hemerocallis fulva variety Flore Full, herbaceous perennial widely used in landscaping. The experimental design was randomized blocks with 25 treatments, arranged in a factorial 5 x 5 (0; 75; 150; 225 and 300 kg ha-1 N and 0, 100, 200, 300 and 400 kg ha-1 P), with 4 replicates. The phosphorus fertilization was carried out 15 days after planting (DAP) and nitrogen was applied in coverage divided in three equal applications at 15, 120 and 240 DAP. There were evaluated the plant height, number of tillers per plant, soil coverage area, the fresh mass of plant, root system and shoot; and the dry mass of plant, root system and aerial part, and calculated the ratio of root dry mass and plant dry mass. It was also obtained the nutrient content of the leaf tissue and root system. The highest tillering was gained with the use of 150 kg ha-1 N combined with 400 kg ha-1 of P. Intermediate doses of N (75-170 kg ha-1 of N) showed higher production of plant fresh and dry mass and root dry mass. Doses of N and P influenced the N and P content in plant tissues of roots and leaves of Hemerocallis. Plants fertilized with 300 kg ha-1 of N and 273 kg ha -1 of P lead to the highest levels of N in the leaves and doses of 80 kg ha-1 of N and 68 kg ha-1 P, the highest content of P in the leaves of H. fulva. Already, in the roots, the highest N content was obtained with application of 300 kg ha-1 N in the presence of P and doses of 225 kg N ha-1 combined with 300 ha-1 P provided the highest P content in the roots.

The salinity is a limiting factor for germination to occur in most species being necessary studies that assess the interaction between plants and saline environment to which they are being associated. The present study had as aim to evaluate the germination and characteristics of vigor in Salvia splendens subjected to salinity. The seeds were exposed to different osmotic potentials, simulating salt stress caused by NaCl, KCl and CaCl2 at potentials of 0, -0.4, -0.8, -1.2, -1.6 and -2.0 MPa. In general, CaCl2 led to the best results for all variables, probably connected to the positive effect of Ca2+ in cell metabolism, allowing germination of 60.81% in the osmotic potential of -1.35 MPa.

In vitro sowing and acclimatization of the produced plantlets are responsible factors for the successful production of Orchidaceae. This study aimed to: 1) evaluate the viability of B. tuberculata seeds stored at different temperatures, and 2) evaluate the ex vitro growth of B. tuberculata on different substrates. The seeds were stored for 84 days under three conditions: ambient temperature (23 ± 2 ° C), refrigerator (4 ± 2 ° C) or freezer (-14.5 ± 2 o C). The completely randomized design was used and treatments were arranged in a 3 (temperature conditions) x 6 (storage period) factorial scheme with three replications. Seed viability was determined by tetrazolium test. For acclimatization, two-year plants coming from in vitro sowing were acclimatized in plastic trays containing: 1 – sphagnum; 2 – charcoal or 3 – coconut fiber. We used the completely randomized design with 3 treatments and 4 replications of 10 plants each. The plants remained in the greenhouse for 365 days under ambient conditions, receiving daily average brightness of 130 ?m-2 s-2. After this period, the plants were evaluated for survival percentage, fresh and dry weight of shoots and roots, and it was calculated the relationship between fresh weight of the plants, the shoot length and the largest root, the number roots and the number of tillers, observed at the end of the experimental period compared to those recorded at planting. For the seed study, after 84 days seeds stored under ambient conditions showed 0.0% viability, while those stored in the refrigerator and freezer showed 77.6 and 67.2% viability. At the end of the acclimatization period, all the relations between the initial and final values were greater than 1.00 indicating that the conditions presented by the three substrates led to the growth of the species, and the percentage of plant survival was around 89%. We conclude that the B. tuberculata seeds should be stored in the refrigerator and that the studied substrates can be used in the acclimatization plants of B. tuberculata .

O gladíolo é uma das flores de corte mais produzidas e comercializadas no Brasil e no mundo. Conduziu-se esse trabalho com o objetivo de avaliar o uso da adubação nitrogenada e potássica associada a diferentes fontes e doses de fósforo na qualidade e durabilidade em pós-colheita de gladíolos (Gladiolus hortulanus L. cv. T704) cultivados em Latossolo Vermelho Distroférrico. Utilizou-se o delineamento experimental em blocos cazualizados e os tratamentos foram arranjados em esquema de parcelas sub-subdivididas. Nas parcelas foram alocadas a presença ou não da adubação nitrogenada e potássica (NK), nas subparcelas as fontes de fósforo (superfosfato triplo, superfosfato simples e farinha de osso) e nas sub-subparcelas as cinco doses de P (0, 75,150, 225 e 300 kg ha-1) dos fertilizantes estudados. As plantas foram avaliadas quanto ao número de botões florais, número de botões coloridos, número de flores abertas, qualidade da folha, qualidade da flor, qualidade da haste, altura da planta, comprimento da espiga floral, diâmetro e durabilidade da flor. Independentemente dos tratamentos e das combinações estudadas, as folhas produzidas foram classificadas como ótimas. A ação conjunta dos três fatores estudados (pforam suficientes para a obtenção da classe I de qualidade de gladíolos. A utilização de superfosfato triplo é mais eficiente quando se objetiva durabilidade das flores e, a de superfosfato simples, quando se objetiva qualidade das hastes florais. Doses de fósforo entre 150 e 160 kg ha-1 são suficientes para obtenção de durabilidade e qualidade das flores e hastes dessa cultivar.

O gladíolo é uma das plantas ornamentais mais cultivadas no Brasil, entretanto poucas são as informações científicas relacionadas à cultura. O objetivo desta pesquisa foi avaliar o efeito da adubação nitrogenada e tamanho do cormo no crescimento e floração de Gladiolus grandiflorus ‘San Remo’. O experimento foi conduzido na área de Jardinocultura da Universidade Federal da Grande Dourados (UFGD) em Dourados – MS. O delineamento experimental utilizado foi inteira­mente casualizado e os tratamentos dispostos em parcelas subdivididas, sendo as parcelas constituídas dos diâmetros dos bulbos (grandes entre 40 e 55 mm; médios entre 20 e 40 mm e pequenos inferior a 10 mm), e as subparcelas de três doses de nitrogênio (30, 50 e 70 kg ha-1), com 10 repetições. Foram avaliados o número de folhas, o comprimento da folha, o início da floração, o número de botões por espiga floral, a durabilidade da flor, a duração da floração e o número de cormilhos. As hastes florais produzidas foram classificadas como Classe III. A adubação nitrogenada foi mais eficiente para o crescimento de cormos de tamanho médio e pequeno, sendo que doses superiores a 50 kg ha -1 promoveram os melhores resultados. Em relação à floração, cormos de tamanho grande e a adubação nitrogenada de 30 kg ha -1 atrasaram seu início. Recomenda-se a utilização de cormos de tamanho médio e adubação nitrogenada de 50 kg ha -1 para o cultivo de Gladiolus grandiflorus ‘San Remo’.

Este estudo, conduzido na área de Jardinocultura da Faculdade de Ciências Agrárias da UFGD de setembro de 2010 a agosto de 2011, teve por objetivo avaliar o crescimento e a floração da espécie Dendrobium nobile Lindl., sob cinco níveis de luminosidade (83, 104, 115, 154 e 237 μmol m-2 s-1) propiciadas por subcoberturas providas de telas de sombreamento de 70, 50, 40, 30 e 0 %, respectivamente. Durante 12 meses, as plantas foram irrigadas e adubadas com NPK 10-10-10 e após este período foram avaliadas quanto ao número, comprimento e diâmetro dos pseudobulbos, sendo calculados os incremen­tos em relação aos dados iniciais. Na época da floração foi contado o número total de gemas, de gemas florais, de gemas vegetativas e de gemas não diferenciadas, registrando-se a antese em cada intensidade luminosa. Utilizou-se o delinea­mento experimental inteiramente casualizado com cinco tratamentos e sete repetições com duas plantas e as médias foram comparadas pelo teste Tukey a 5% de probabilidade. Todas as condições de luminosidade foram favoráveis ao cultivo de D. nobile, sendo registrados acréscimos médios de 36,7%, 16,0% e 16,2% no número, no diâmetro e no comprimento de pseudobulbos, respectivamente. O maior número de gemas florais foi observado na condição de 104 μmol m-2 s-1. D. nobile pode ser cultivada em condições de luminosidade variando de 83 a 237 μmol m-2 s-1, recomendando-se a luminosidade de 104 μmol m-2 s-1, como forma de promover sua floração.