Maria Cristina Stolf Nogueira

In vitro shoot regeneration from roots and leaf discs of Passiflora cincinnata mast.

Different concentrations of 6-benzyladenine (6-BA) were used in vitro to induce buds in three types of explants: leaf discs, root segments and the seedling itself obtained from in vitro seed germination of Passiflora cincinnata Mast. The 0.5 mg.L -1 6-BA concentration was most suitable for all the three explants, however, bud formation time and means (direct/indirect) were different for each type of explant. In seedlings used as explants, it had shoot regeneration from the primary root. Histological events leading to bud formation via meristemoids were described. The origin was indirect in leaf discs, with callus formation in subepidermal cells of the chlorophyll parenchyma layers. In root segments and in seedling roots, the buds were formed directly in the pericycle (in roots with some secondary structure) and in the vascular cambium (at the initial phase of secondary structure). Also, indirect buds originated from meristemoids which were formed around the callus.

Root growth of cane rattoons harvested green or burned

Este trabalho teve como objetivos comparar o crescimento de raizes de cana colhida crua, mecanizada e de cana apos a queima, colhida manualmente; avaliar a influencia do clima sobre as duas condicoes de crescimento e analisar o comportamento do crescimento de raizes de cana crua e cana queimada nos 1o e 2o anos de rebrota, atraves de curvas adaptadas. A pesquisa foi realizada no municipio de Morro Agudo, SP, de julho de 1995 a julho de 1997. A cultivar utilizada foi a SP 70-1143. Utilizou-se como indicadores de crescimento das raizes a materia seca e o perfil delas no solo. Avaliou-se a influencia das temperaturas e das umidades do ar e do solo sobre os tratamentos. Observou-se que o crescimento, no primeiro e no segundo ciclo, nao apresentou curvas que indicassem um padrao semelhante, tanto para cana crua, como para cana queimada, os fatores climatologicos, isoladamente, nao provocaram mudancas nos ciclos de crescimento de maneira que se identificasse uma tendencia geral. As raizes aparecem em maior quantidade em todas camadas do solo em cana crua do que em cana queimada, no primeiro ano e no segundo ano aparecem maiores em cana queimada.

Orthogonal contrasts: definitions and concepts

The single degree of freedom of orthogonal contrasts is a useful technique for the analysis of experimental data and helpful in obtaining estimates of main, nested and interaction effects, for mean comparisons between groups of data and in obtaining specific residuals. Furthermore, the application of orthogonal contrasts is an alternative way of doing statistical analysis on data from non-conventional experiments, whithout a definite structure. To justify its application, an extensive review is made on the definitions and concepts involving contrasts.

Fertigation with saline water and its effects on yield of greenhouse grafted cucumber

A aplicacao de fertilizantes via agua de irrigacao nos cultivos protegidos, bem como a utilizacao de agua subterrânea com alta concentracao salina, tem resultado no aumento da salinidade do solo, ocasionando perdas de produtividade. Este trabalho teve o objetivo de avaliar a producao da cultura do pepino enxertado, cultivado em ambiente protegido, quando irrigado com aguas de diferentes condutividades eletricas (S1=1,54; S2=3,10 e S3=5,20 dS.m-1) e duas lâminas de irrigacao associadas as suas frequencias de aplicacao (L0=1,00.ETc; L1F1=1,25.ETc em todas as irrigacoes e L1F2=1,25.ETc quando a lâmina de agua de irrigacao acumulada em L0 atingia 100 mm), sendo ETc a evapotranspiracao da cultura. O ensaio foi conduzido em blocos casualizados com tres repeticoes e os fatores foram arranjados no esquema fatorial 3x3. O numero de frutos comerciais por planta reduziu linearmente com o aumento da salinidade, enquanto a producao total e comercial, bem como o numero total de frutos por planta e a producao de materia seca de frutos nao foram afetados significativamente pela salinidade, embora todas as caracteristicas tenham apresentado tendencia de reducao com o aumento da salinidade da agua de irrigacao. As diferentes lâminas de irrigacao nao foram suficientes para reduzir os efeitos do estresse salino, independente das suas frequencias de aplicacao.

Contrastes ortogonais na análise do controle de volatilização de amônia em compostagem

ABSTRACT: Orthogonal contrasts have been very useful in the analysis of experiments and this techniquehas been efficient in obtaining estimates of main, interaction and nested effects. Generally this technique hasbeen useful for the analysis of data from non-conventional experiments, with no defined structure. The aim ofthis work was to apply this technique to the data obtained by an experiment to control losses of ammonia byvolatilization with different levels of residual acidity associated with three levels of additives, and four ratelevels. In this way the statistical analysis was carried out according to a one-way layout in a mixture with anadditional treatment. The main effects of additives and rate as well as the nested and interaction effects wereestimated using orthogonal contrasts. This technique is an alternative form to analyze non-conventionalexperiments in order to extract all the effects involved in the analysis.Key words: composting, volatilization, additional treatment, orthogonal contrast

Decomposição da interação tripla significativa utilizando o comando contrast do PROC GLM do SAS aplicado ao modelo de classificação tripla para dados balanceados

ABSTRACT TRIPLE INTERACTION FRACTIONING USING PROC GLM CONTRAST/SAS,APPLIED TO A THREE-WAY LAYOUT FOR BALANCED DATAIn a three-way analysis of variance, in which significant interaction among the involved factors isdetected, it might be important to get the fractioning of the interaction degrees of freedom added tothe degrees of freedom of the involved factors. In the case of a significant triple interaction, the effecetof one nested factor is usually checked against the combined effect of the remaining factors. The mainaim of this research work has been to get the sum of squares of such effect through the CONTRAST command of PROC GLM , available in the SAS computer program. The feasibility of checkinghypothesis and the application of orthogonal contrasts is evaluated through the checking of theobtained results. A numerical example is provided. Key words: three-way layout, interaction, decomposition of interaction. 1. INTRODUCAO Os modelos de classificacao tripla para dados ba-lanceados tem-se mostrado de grande utilidade naexperimentacao agronomica. Segundo K

Quadrados latinos obtidos por meio de técnicas de confundimento em ensaios fatoriais

Latin square designs have been very useful in agriculture and animal sciences. They are, in general, obtained following algebrical rules from basic operations for positive integers and the m-modular number system. In this way, from an experiment installed in a factorial scheme, it is possible to obtain as many latin squares as the levels of treatments, through the use of a confounding technique. These schemes lead to orthogonal replications of latin squares. The aim of this work was to evaluate this technique in order to facilitate plannings. An example of a 3 x 3 x 3 factorial design without replications is presented.

Aplicação do resíduo específico na análise de grupos de experimentos

The main aim of the analysis of groups of experiments is to produce information that can be applied to a population either in space or in time and in both. The aim of this paper is to apply the specific error technique in order to solve the heterogeneity problem of the interactions of experiments with treatments, and to obtain the expectations of the mean squares for the considered effects in the analysis of variance. The data that were used refer to a group of 11 experiments, in a 33 factorial design with sugar cane, conducted at different places of Sao Paulo State, Brazil. The results showed that the specific error technique is adequate when the heterogeneity is present in the interactions.

Specific residue: application of orthogonal contrasts when heteroscedasticity is present

When experimental data are submitted to analysis of variance, the assumption of data homoscedasticity (variance homogeneity among treatments), associated to the adopted mathematical model must be satisfied. This verification is necessary to ensure the correct test for the analysis. In some cases, when data homoscedascity is not observed, errors may invalidate the analysis. An alternative to overcome this difficulty is the application of the specific residue analysis, which consists of the decomposition of the residual sum of squares in its components, in order to adequately test the correspondent orthogonal contrasts of interest between treatment means. Although the decomposition of the residual sum of squares is a seldom used procedure, it is useful for a better understanding of the residual mean square nature and to validate the tests to be applied. The objective of this review is to illustrate the specific residue application as a valid and adequate alternative to analyze data from experiments following completely randomized and randomized complete block designs in the presence of heteroscedasticity.