Sidney Fernando Caldeira

Desbaste seletivo em povoamentos de Tectona grandis com diferentes idades

The intensity of the first selective thinning was evaluated in two plantations, 3.0 x 3.0 m. In the four year old plantation, the thinning was 20%, 30% and 40% in density and in the five year old, it was 30%, 40% and 50%, and the respective controls (0%). Each treatment was applied in eight random blocks of 35 trees, beyond the border. One year after thinning at the age of four, the DBH, total height (H), and average by tree of basal area ( ) and of volume ( ) presented no differences among the treatments; the current annual increment (CAI V ) was not affected by the intensities. In the plantation thinned at the age of five, the CAI V and H were similar in all treatments; the DBH, and were not affected by the tested intensities, but they were greater than the control. The first selective thinning may be applied at the age of five, in Tectona grandis plantations with similar conditions, at any tested intensity.

Geostatistical Modeling of Site Index Classes in Teak Stands

More realistic estimates of a local productive capacity, and thus reliable maps of site index, can be obtained in unsampled locations of a forest site when one chooses from among appropriate spatial characterization techniques. This study aimed apply and compare geostatistical modeling techniques to estimate dominant height and to map site index classes in teak stands in the Mato Grosso State, Brazil. Samples were taken and the average dominant height was obtained annually between the 2 nd

GEOSTATISTICAL MODELING OF TIMBER VOLUME SPATIAL VARIABILITY FOR Tectona grandis L. F. PRECISION FORESTRY

Considerando a hipotese de que os volumes de madeira apresentam dependencia espacial, cujo conhecimento contribui para o manejo de precisao, o objetivo deste trabalho foi estimar a variabilidade espacial do volume de sortimentos de madeira e identificar seus padroes espaciais em povoamentos de Tectona grandis. Utilizou-se um conjunto de dados de 1.038 arvores para ajustar funcoes de afilamento e estimar os volumes para fuste total, serraria e lenha em 273 parcelas alocadas em povoamentos de T. grandis ao oitavo ano de idade, o qual representa o segundo desbaste que possibilita volumes comerciais. Modelos de semivariogramas foram aplicados para ajustar a dependencia espacial e a krigagem pontual foi utilizada para compor mapas de volume. A modelagem geoestatistica permitiu estimar a variabilidade espacial de T. grandis e desenvolver mapas de volume de madeira. Assim, tratamentos silviculturais, como desbaste e poda, bem como planejamento de intervencoes espaciais, podem ser recomendados para produtos de madeira almejados.

VARIABILIDADE ESPACIAL DOS ATRIBUTOS QUÍMICOS DO SOLO EM POVOAMENTO DE Tectona grandis

Considerando a necessidade por informacoes que visem a identificar e medir as relacoes espaciais dos fatores edaficos que limitam o desenvolvimento dos povoamentos de teca, neste trabalho, objetivou-se caracterizar a variabilidade espacial dos atributos quimicos pH, fosforo, potassio, calcio, magnesio, materia orgânica e aluminio do solo e compara-las em dois periodos de avaliacao, ao segundo e nono ano de idade, de um povoamento de teca no estado de Mato Grosso, Brasil. Foram alocadas 46 unidades amostrais e coletadas amostras de solo, a 0-0,2 m de profundidade, para a posterior modelagem geoestatistica. Foram observadas alteracoes espaciais dos atributos quimicos do solo entre as avaliacoes, o que permite recomendar adubacoes e correcoes de acidez do solo em regioes especificas da area florestada, visando ao estabelecimento dos individuos pos-plantio e o desenvolvimento daqueles conduzidos pos-desbastes.

Qualea grandiflora Mart.: TEMPERATURA NA GERMINABILIDADE DE SEMENTES

Qualea grandiflora Mart. ocorre em matas de galeria e cerrado, sendo conhecida popularmente como pau- terra. Com o objetivo de obter informacoes sobre a propagacao reprodutiva dessa especie foi estudado o efeito da temperatura sobre a germinabilidade das sementes. As temperaturas utilizadas foram: 15, 20, 25, 30, 35 e 40 oC. As sementes foram semeadas em substrato papel-toalha, na forma de rolo, com quatro repeticoes, sendo a unidade experimental constituida por um rolo com 25 sementes. O experimento seguiu o delineamento inteiramente casualizado com seis tratamentos e quatro repeticoes. Houve emissao de raiz primaria em temperaturas de 15 a 40 oC. Valores entre 78 e 93 % foram obtidos numa ampla faixa de temperaturas, entre 15 e 35 oC. A formacao de plântulas normais ocorreu em faixa mais restrita, entre 20 e 35 oC. A protrusao de raiz iniciou no setimo dia apos a semeadura, exceto a 15 oC que proporcionou um processo lento e gradativo, iniciando no decimo quarto dia apos a incubacao. A 40 oC a germinabilidade foi inferior a 15 % e nao houve formacao de plântulas normais. Para germinacao de sementes de pau-terra, recomenda-se a faixa de temperatura entre 20 e 30 oC.

Capacidade produtiva de Tectona grandis L.f no Sudoeste de Mato Grosso

The knowledge of the site is necessary to understand the production and forest management. The objective of this study was to determine the productive capacity of Teak in southwestern Mato Grosso State, through the analysis of site index curves, to forest harvesting. The data were collected in permanent plots and the stem analysis of 32 dominant trees of two stands, 33 and 34 years old. Eight site index models were adjusted and the selection criteria followed the lowest standard deviation, the highest adjusted coefficient of determination, F test value and the absence of trends in the graphical analysis of the residuals. The site index curves were prepared by the method of the guide curve. Soil samples were collected for physical analysis and macronutrients. The model presented by Hoerl had the best fit and it was found that the database follows an anamorphic pattern, thus, the growing trend is the same between the curves. Four site index curves were generated in an age-index of 30 years and three productivity classes of Teak were established. The soil characteristics of the region are favorable to the cultivation of Teak and the curves illustrate the productive potential for the species.

Herbicidas e danos físicos em tocos de teca para controle de brotos após o desbaste

The stumps of thinning trees of Tectona grandis L.f. present intense sprouts that compete with the remaining trees. The efficacy of the control of sprouts with the herbicides picloram and triclopyr, associated or no it applications of physical damages, were evaluated. Immediately after thinning, in plantation with four years old, the stumps were treated, and in other plantation, with age of six, the sprouts of stumps thinned in the previous year, were treated. The percentage of died stumps, the number of sprouts by stump and the respective heights were registered. In the first trial, the combined application of picloram at 0.48% with triclopyr at 0.96%, associated a 20 cracks with axe killed all stumps. In the second trial, the best efficacy, 21.7%, was obtained with the previous mowing of sprouts and application of picloram at 0.96%. After thinning, the isolated application of picloram or combined with triclopyr, associates or not a physical damage is efficient to control sprouts of teak. The application in the sprouts of stumps thinned in the last year present any efficiency, with least percentage of dead stumps in relation to application after thinning.

Desenvolvimento in vitro do fungo simbionte de Atta sexdens rubropilosa Forel, 1908 (Hymenoptera: Formicidae) em meio de cultura com diferentes extratos vegetais

The objective of this study was to evaluate the in vitro development of Leucoagaricus gongylophorus, the symbiotic fungus of Atta sexdens rubropilosa in culture medium added with extracts of 24 plant species. The fungus was inoculated in PDA added with vegetables extracts and four controls, in Petri dishes. The dishes were maintained in climate chambers at temperature of 25±1°C in the dark, to period of 42 days. The fungal growth was evaluated weekly by diameter of the colony. The results showed that the symbiotic fungus of these ants has differentiated growth when compared to the extracts provided in the dishes, and the medium supplemented with extracts of arica (Physocalymma scaberrimum), cerejeira (Amburana acreana), cedro (Cedrela fissilis), timbo (Magonia pubescens), leucena (Leucaena leucocephala) e mogno (Swietenia macrophylla) hampered the development, however the extracts of genipapo (Genipa americana), seringueira (Hevea brasiliensis), inga (Inga edulis) e cambara (Vochysia divergens) had better conditions for the development of the symbiotic fungus.

Envelhecimento acelerado como teste de vigor para diásporos de aroeira (Myracrodruon urundeuva Fr. Allem)

This work established the adequate temperature and the period of exposition for the accelerated ageing test with diasporas of Myracrodruon urundeuva from an area of the Cerrado in the state of Mato Grosso, Brazil. Before and after the ageing, at the temperatures of 40oC, 41oC, 42oC and 45oC combined with periods of 12, 18, 24, 30 and 36 hours, the water content and germination were evaluated. For each treatment, 12g of diasporas in mini chambers with 40 mL of distilled water were submitted to the accelerated ageing test. A total of 100 diasporas, divided into four replications, in plastic boxes, on two sheets of blotting paper, in germinator at 25oC and 8 hours of photoperiod were germinated. In all treatments the content of water of the aged diasporas was superior to 20% and this value stabilized itself between 25% and 28%, from the 18 hours of exposition. Independently of the tested periods, the ageing at the temperatures of 40oC, 41oC and 42oC did not affect the germination. After the ageing at 45oC, the germination did not differ among the periods of 12, 18 and 24 hours of exposition, but in all these periods it was inferior to the control and superior to the periods of 30 and 36 hours. In these last two periods, fungi were observed. The accelerated ageing of diasporas of Myracrodruon urundeuva should be conducted at the temperature of 45oC, during the exposition periods of 12 to 24 hours.

Potencial fisiológico de diásporos de Tectona grandis L.f. derrubados pelo vento

In the seed production areas of Tectona grandis in Caceres, state of Mato Grosso, Brazil, strong winds cause the precocious fall of fruits. Diasporas of three lots of teak, one of then crop after the natural fall, and the others two after the precocious fall were characterized initially by the content of water, thousand diasporas mass, number of diasporas by kilogram, emergency in seedbeds and respective average time. With 200 diasporas divided in four replications and in periods of 50 days until 331 days after crop, the last two variables were determined again. To the diasporas of natural fall, the seedlings emergency and the average time were not different in periods of analyses with a general average of 60.6% and 10.8 days. The diasporas of the precocious crop lots presented respectively the initial emergency of 23.5 and 17.5% and the average time of 19.4 and 22.6 days. Until 115 days after crop, the emergency increased (55.5 and 59.5%) and the average time diminished (15.0 and 14.1 days) and on this point the inverse occurred. The diasporas of precocious crop fall by the wind present maturation and the greater physiological potential at 115 days after the crop. In the period at 64 to 269 days after crop, these diasporas reaches the established minimum standard for the teak and at 115 to 165 days is more adjusted period for its use.