João Alexandre Lopes Dranski

Physiological maturity of seeds and colorimetry of fruits of Jatropha curcas L.

The objective was to relate the coloration of fruits of Jatropha curcas L during the maturation process with morphometric (fruits and seeds) and germinative characteristics (seeds). Fruits were collected at various maturation stages from mast trees located in Eldorado/MS, and six maturation stages were visually classified based on fruits epicarp color. Epicarp digital colorimetry was used to characterize maturation stages in addition to morphometric variables of length and width of fruits and seeds, as well their water content. For determining the physiological potential it was used germination test, emergence velocity index and first count of germination. Results indicated that seeds of J. curcas should be harvested when fruit epicarp shows a reading equal or smaller than 82, 70 or 65 nm of red, green or blue scales from a digital color analyzer. Seeds of fruits with that colorimetry can be harvested in virtue of the maxim acumululation of dry mass, water content below 38,5% and higher physiological potential.

Storage of physic nut seeds in different environments and packaging

Sementes de pinhao manso (Jatropha curcas L.) possuem caracteristicas ortodoxas e requerem conhecimento sobre os fatores que afetam a manutencao de sua qualidade fisiologica. Assim, objetivou-se neste estudo identificar as condicoes adequadas de armazenamento para a manutencao da qualidade fisiologica de sementes de pinhao manso. Na avaliacao dos metodos de armazenamento, utilizou-se delineamento inteiramente casualizado, em esquema fatorial 3x3+1, sendo os fatores constituidos por tres embalagens (saco de papel Kraft, saco de polietileno e embalagem de vidro), tres ambientes de armazenamento (laboratorio com condicoes nao controladas, câmara refrigerada a 14 - 16 oC e refrigerador a 4-6 oC) e avaliacao inicial do material em estudo. Foram analisados os valores de teor de agua, primeira contagem de germinacao em ambiente controlado. Tambem se avaliou o indice de velocidade de emergencia, porcentagem de germinacao das sementes e Indice de Qualidade de Dickson para as mudas apos 45 dias da semeadura em ambiente propagativo nao controlado. As sementes armazenadas em embalagem de vidro e ambiente de geladeira mantiveram a sua qualidade fisiologica, podendo ser armazenadas pelo periodo de 180 dias.

Sobrevivência e crescimento do pinhão-manso em função do método de aplicação e formulações de hidrogel

This study compared the effects of formulations and methods of hydrogel application on the survival and initial seedling growth of physic nut (Jatropha curcas L.). The study was conducted in Pato Bragado, PR during 2009 and 2010. The experimental design was in randomized blocks, arranged in a 5 x 2 factorial composed by five formulations of hydrogel (0, 2.5, 5.0, 7.5, and 10.0 g L-1) and two application methods (immersion of roots into hydrogel previously hydrated and application of 0.5 L directly in the planting hole). Measurements included the percentage of survival, seedling height and diameter increments, and number of branches three and eighteen months after planting. The analysis with three months data revealed significant effects (p 0.05) was observed for the application methods or hydrogel formulations. The use of 0.5 L of a 7.0 g L-1 of hydrogel directly into the planting hole favored significantly the establishment of physic nut seedling and formulations above the suggested concentration reduced seedling growth in western Parana.

EFEITO DA TIGMOMORFOGÊNESE NA MORFOMETRIA DE MUDAS DE Maytenus ilicifolia (Schrad.) Planch.

O presente estudo objetivou quantificar alteracoes morfologicas decorrentes de estimulos mecânicos por flexoes caulinares na fase de rustificacao de mudas de espinheira-santa [Maytenus ilicifolia (Schrad.) Planch.]. O experimento foi conduzido em casa de sombra sob delineamento experimental inteiramente ao acaso em arranjo fatorial 2 x 5, formado por mudas divididas em duas classes quanto a altura da parte aerea e cinco intensidades de flexoes caulinares (0, 5, 10, 20 e 40) efetuadas diariamente durante trinta dias, em quatro repeticoes de dez mudas. O efeito dos estimulos mecânicos foi quantificado pelos incrementos na altura, no diâmetro do coleto, assim como pela mensuracao da biomassa de raiz e da parte aerea com os quais se determinou a taxa de crescimento absoluto. Complementarmente, foi mensurada a perda de eletrolitos de raizes. Os dados foram submetidos a analise de regressao a 5%. Os resultados indicaram que o aumento do numero de flexoes caulinares induziu a reducao no incremento em altura, no extravasamento de eletrolitos dos tecidos radiculares e, no aumento do incremento no diâmetro do coleto e na biomassa de raizes em mudas classificadas por altura. A biomassa da parte aerea de mudas com maiores dimensoes aumentou com ate 20 flexoes mesmo com a reducao linear na altura e, consequentemente, elevou a taxa de crescimento. Estimulos mecânicos por meio de flexoes caulinares e uma opcao para promover alteracoes morfologicas em mudas de Maytenus ilicifolia elevando a rusticidade e a qualidade das mudas aptas ao plantio.

EFEITO DOS ÁCIDOS INDOLBUTÍRICO E NAFTALENOACÉTICO NO ENRAIZAMENTO DE ESTACAS SEMILENHOSAS DE Cordia trichotoma (Vell.) Arrab. ex Steud.

This study aimed to evaluate the effects of different concentrations of the indolbutiric acid and α-naphthalene acetic acid on the rooting of semi-woody cuttings, collected from the sprout of Cordia trichotoma seedlings. Seedlings were produced by seeds constituting a miniclonal garden with subsequent pruning of the aerial part. Sprouts were harvested resulting in semi-woody cuttings with 12.0 cm long and 5.5 mm in diameter and a pair of leaves in the apical portion reduced in a half. The treatments consisted of fast immersion of the cuttings base in indolbutiric acid (IBA) and α-naphthalene acetic acid (NAA) in concentrations of 0, 2.000, 4.000, 6.000, 8.000 mg L-1 in a randomized block design with bifactorial arrangement 2 x 5. After 60 days of cutting, rooting percentage, roots number and length, sprouting percentage, the number of shoots and new leaves were evaluated as well as the survival and mortality. The phytoregulator IBA at a concentration of 8.000 mg L-1 promoted greater rooting, resulting in 28.9% of the cutting rootings, and greater number of roots per cutting. For the NAA, there was no significant effect on rooting. The increasing concentration of phytoregulators linearly reduced the emission of new leaves and shoots, and increased linearly cutting mortality, negatively affecting the components of the shoot of semi-woody cuttings of Cordia trichotoma.

Vigor of canola seeds through quantification of CO2 emission

A semente marca o inicio da producao de graos de plantas cultivadas. Assegurar a qualidade da semente e a prioridade da tecnologia de sementes. Neste contexto, o trabalho objetivou aferir o uso da concentracao de dioxido de carbono na classificacao de sementes de Brassica napus de diferentes niveis de qualidade resultante de diferentes datas de semeadura. nos quais avaliou-se a porcentagem de plântulas normais e o indice de velocidade de germinacao. A concentracao CO2 foi quantificada em amostras mantidas por cinco periodos de incubacao a 40 °C e mensuradas com o auxilio de um medidor de trocas gasosas, acoplado a um sistema de injecao e fluxo de ar. Os resultados foram submetidos a analise de variância e as medias comparadas pelo teste de Duncan e pela analise de regressao a 5%. Os resultados da porcentagem de plântulas normais foram correlacionados com os resultados da concentracao de CO2. Sementes de B. napus apresentaram alta porcentagem de plântulas normais. Contudo, para o indice de velocidade de germinacao houve possibilidade de classificacao em pelo menos duas classes de vigor. A determinacao da concentracao de CO2 foi mais eficiente apos tres horas de incubacao, sendo possivel agrupar os lotes em quatro Classes de vigor. A concentracao de CO2 foi inversamente proporcional a porcentagem de plântulas normais, com melhor coeficiente de correlacao obtido apos tres horas de incubacao.

Maturidade fisiológica de sementes e colorimetria dos frutos de Allophylus edulis [(A. St.-Hil., A. Juss. & Cambess.) Hieron. ex Niederl.]

This study aimed to determine the physiological maturity of A. edulis seeds, check if this is achieved in the same maturation stage, regardless of the collection region and, colorimetry of the fruit can be indicative of the time of harvest. Fruits were harvested in three counties of the western region of Paraná and visually classified into five ripening stages according to the color of the pericarp with the help of a digital colorimeter. Analyzed seed variables included morphological characteristics, germination and vigor. The experiment was conducted in a completely randomized design with four replications. The maximum dry matter accumulation of seeds was reached when the fruits reached the color orange. With the advance of the ripening process, red color fruits had seeds with lesser moisture content, coinciding with the maximum germination percentage and speed, besides generating seedlings with larger size and biomass accumulation. The green spectrum allowed to discriminate maturity from different places of harvest. A. edulis seeds with physiological maturity should be harvested when fruits present the red color, independent of the harvesting region or, with reflectance values between 28.0 and 49.2 nm in the green range of the color spectrum.

Avaliação morfofisiológica em mudas de Handroanthus impetiginosus (Mart. ex DC.) Mattos durante a rustificação

The present study aimed to quantify the effects of hydric management during the hardening process of Handroanthus impetiginosus seedlings by means of foliar thermography and morphometric parameters of quality. Irrigation treatments of 60 seedlings each were carried out at the following frequencies: daily (control), and every two, three, and four days for four weeks. Measures of leaf temperature (LT), height increment, collar diameter, and root dry mass were performed. Quantification of LT occurred at the end of each irrigation management cycle and analysis of the other variables studied was performed at the beginning and end of the hardening process. Seedlings of H. impetiginosus irrigated daily presented higher diameter increment in relation to those irrigated every three days, and the seedlings irrigated every four days showed higher root system growth and reduction of aerial part growth. The use of infrared thermometry allowed LT assessment in seedlings of H. impetiginosus during hardening. It was possible to verify that the longer the water stress period, the higher the leaf temperature, with the highest temperature observed in seedlings irrigated every four days.

Avaliação Morfofisiológica em Mudas de Handroanthus impetiginosus (Mart. ex DC.) Mattos Durante a Rustificação / Morphophysiological Evaluation in Seedlings of Handroanthus impetiginosus (Mart. ex DC.) Mattos During Hardening

The present study aimed to quantify the effects of hydric management during the hardening process of Handroanthus impetiginosus seedlings by means of foliar thermography and morphometric parameters of quality. Irrigation treatments of 60 seedlings each were carried out at the following frequencies: daily (control), and every two, three, and four days for four weeks. Measures of leaf temperature (LT), height increment, collar diameter, and root dry mass were performed. Quantification of LT occurred at the end of each irrigation management cycle and analysis of the other variables studied was performed at the beginning and end of the hardening process. Seedlings of H. impetiginosus irrigated daily presented higher diameter increment in relation to those irrigated every three days, and the seedlings irrigated every four days showed higher root system growth and reduction of aerial part growth. The use of infrared thermometry allowed LT assessment in seedlings of H. impetiginosus during hardening. It was possible to verify that the longer the water stress period, the higher the leaf temperature, with the highest temperature observed in seedlings irrigated every four days.

Effect of ethephon on hardening of Pachystroma longifolium seedlings

Immediately after planting, tree seedlings face adverse environmental and biotic stresses that must be overcome to ensure survival and to yield a desirable growth. Hardening practices in the nursery may help improve seedling stress resistance through reduction of aboveground plant tissues and increased root volume and biomass. We conducted an assay to quantify changes in the morphogenesis following application of ethephon on seedlings of Pachystroma longifolium (Ness) I. M. Johnst.during hardening. The results showed no effect of the ethephon treatments on the number of leaves but a reduction of up to 50% in seedling height increment, and an increase in stem diameter increment of up to 44% with the 600 mg L -1 ethephon treatment, which consequently altered seedling Dickson Quality Index. Our results indicate that ethephon may help to promote desired morphological changes that occur during seedling hardening in nurseries.