Susana Cristine Siebeneichler

Densidade de plantio em duas cultivares de mamona no Sul do Tocantins

Abstract - In order to improve the system of production of castor oil, you need to determine the density of plants. It was conducted an experiment in the Cariri, Tocantins-TO, at the Fazenda Coqueiro, using seeds of BRS Nordestina and BRS Paraguacu to verify the effect of five planting densities (2.5; 3.12; 4.16; 6.25 and 12.5 thousand plants ha -1 ) on yield and agronomic characteristics of castor. The experiment was installed in February 2006 with all plants receiving the same fertiliza tion independent of density (NPK 5-25-15). The experimental design was randomized blocks with four replications and treatments arranged in a 5 x 2 x 3, for analysis of grain yields and in a 5 x 2 for the other traits evaluated. The treatments resulted in the combination of five densities (distance between plants growing 2.00; 1.60; 1.20; 0.80 and 0.40 m) for the 2.5; 3.12; 4.16; 6.25 and 12.5 thousand plants per hectare respectively, two cultivars (BRS Nordestina and BRS Paraguacu) and three crops of fruit on the following dates: 06/07/2006; 03/08/2006 and 19/09/2006. Among the populations, the highest productivity was 12.5 thousand plants ha

Desenvolvimento inicial de plântulas de Theobroma grandiflorum (Willd. ex Spreng.) Schum. sob influência de sombreamento

The objective of this work was to evaluate the initial growth of sapling of Theobroma grandiflorum (cupuacu), in function of different levels of solar radiation. Fifty days, after the emergency, the saplings were submitted to three levels of shade, being: 0%, 50% and natural shade. Sapling development was carried out in randomized block design with 15 repetitions (15 saplings). The sapling height, lap diameter and the numbers of leaves being evaluated on the 60 st , 82 nd , 103 rd , 124 th , 145 days after sapling emergence. The Dry Mass of the leaves (DML), Dry Mass of the stem (DMS), Dry Mass of the root (DMR) and Dry mass of the plant (DMP), Relation shoot/root (PA/R) and relation plant height/Lap diameter, were measured at the end of the experiment, when the sapling reached the appropriate size to be planted in the field. The initial growth of Theobroma grandiflorum was corroborated with the species standard that occurs inside of the primary bushes, so its development of the parameters evaluated is better in conditions of 50% of shade. The condition of 50% of shade can be recommended for the formation of plants of Theobroma grandiflorum , which had the better performance in plant height, lap diameter, number and allocation of mass in the parts of the plant.

Composição mineral da folha em abacaxizeiro: efeito da parte da folha analisada

The standardization of the sampling for foliar analysis in pineapple is important to obtain reliable results. In this aspect this work seeks to identify the variation of the mineral composition of pineapple leaf, in plants developed in sandy soil, without irrigation. The leaves were collected, cleaned and divided in 4 parts: non-chlorophyllated, basal, medium and apical. After the drying, the samples were weighted, digested, and analyzed by the appropriate methodology for each nutrient. A great variation in the concentration of the nutrients was found along the pineapple leaf. A reliable comparison of the analysis can be established between the whole leaf and the chlorophyllated portion of the leaf; the same does not apply to the non-chlorophyllated portion of the same leaf. This paper confirms the need of the standardization of leaf sampling for mineral composition evaluation.

Deficiência de boro na cultura do abacaxi 'Pérola'

aBSTRacT twenty pineapple ‘Perola’ plants were cultivated in 10l plastic pots in a greenhouse, with the objective of characterizing the visual symptoms of boron deficiency in the pineapple leaves and fruit. the pots contained river sand that was washed five times with common water and two times with deionized water. ten plants were irrigated five months after planting with a complete nutrient solution and the other ten, without b in the solution. the plants presented regular vegetative growth and fruit formation. after the harvest of the fruit, the formation of shoot and suckers seedling types were accompanied, where it was possible to observe that plants were grown without b produced more seedling from the shoot type than from those ones grown with b. the formation of suckers was not affected by the suppression of b from the nutrient solution. Symptoms of boron deficiency were observed only in the fruiting period in plants in the second cycle of growth. Symptoms of b deficiency were characterized by deformed and smaller fruit, with formation of cork tissue or gum secretion among the fruitlets and cracks filled out with of cork tissue. Slip formed in second cycle plants had leaves with uneven borders and dry tips.

Genetic divergence and phosphorus use efficiency in the soybean with a view to biodiesel production

The soybean has an important role in the area of biodiesel, due to having a productive potential and technical feasibility able to meet the growing demand for renewable fuels. In the agricultural year of 2009/10, four competitive trials of soybean cultivars were carried out, two on the Campus of Palmas University and the other two on the University Campus at Gurupi, with a study of genetic divergence being undertaken. At each location, the cultivars were trained under conditions of both high and low phosphorus (150 kg ha -1 P 2 O 5 and 30 kg ha -1 P 2 O 5 respectively). The experimental design employed for each trial was of randomised blocks with three replications and 11 treatments. The percentage of oil as a characteristic was studied, and the efficiency of phosphorus usage by the cultivars determined employing the methodology adapted from Fischer (1983). Genetic divergence was evaluated using multivariate procedures: the generalised Mahalanobis distance and Tochers optimisation method for clustering. In the study of genetic divergence, each test represented a distinct variable in the multivariate model. The cultivars M-SOY 9350, M 8766RR and BR/EMGOPA 314 are the most suitable for the production of biodiesel. The hybrids M 8766RR x M 9056RR, BR/EMGOPA 314 x M 9056RR, P98R91 x M 9056RR are promising for obtaining segregating populations to be used for their oil content.

Qualidade fisiológica de sementes de milho sob diferentes condições de armazenamento

This study aims to examine the quality of corn seeds stored under different conditions from May to October, 2008. The experiment was conducted at the Research Laboratory of Seed Analysis of Federal University of Tocantins, Gurupi Campus, with seeds of commercial cultivars of corn obtained in the F2 generation, stored under the environmental conditions of the state of Tocantins, and in cold chamber (20 °C, and relative humidity of 20%). In order to obtain the salt stress, solutions of potassium chloride (KCl) were used in the following concentrations (mol m-3): zero (T1), 30 (T2), 90 (T3), 170 (T4) and 260 (T5). In order to evaluate the quality of seeds, the following tests were made: germination, germination speed index, seed health and seedling length. The experimental design was a randomized complete block with three replications in a factorial 2x5 (storage conditions x concentration of KCl). Subsequent analysis of ANOVA and application of Tukeys test at 5% were carried out. The average percentage of seed germination was 3.86% and 94% for the storage environmental conditions and cold chamber, respectively. At the highest concentration of KCl, seedlings were 18.33 mm seedling-1 shoot length, and at the lowest concentration, the control, 74 mm seedling-1. The results showed that environmental conditions from May to October in Gurupi, state of Tocantins, are not suitable for storage of seed corn without refrigeration.