Determination of fiber length and juvenile and mature wood zones from Hevea brasiliensis trees grown in Brazil

The aim of this study was to verify the average fiber length and the juvenile and mature wood zones from Hevea brasiliensis proveniences from a reforestation area in São Paulo, Brazil. For this purpose, five Hevea brasiliensis trees were randomly collected from a 50-year-old plantation, located in Balsamo, São Paulo, Brazil. The trees were cut and five flat sawn boards were obtained. The juvenile and mature wood zones were determined by fiber length measurement from the pith to the bark. The results showed that: (a) the juvenile wood of this species occurred approx. between 40 and 55 mm, from the pith, and from this point forward, the mature wood zone was found; (b) there was a significant difference between the average fiber length of juvenile wood (1.26 mm) and mature wood (1.51 mm).

Ambrosia and bark beetles (Scolytidae : Coleoptera) in pine and eucalypt stands in southern Brazil

More than 95% of the reforested area in Brazil is covered by exotic Eucalyptus and Pinus plantations. Native Scolytidae, mostly ambrosia beetles, appear to be rapidly adapting to these exotic trees, and reports of economic damage are becoming frequent. The objectives of our research were to survey, characterize and compare the Scolytidae fauna present in a P. taeda and an E. grandis stand in Telemaco Borba, Parana state, Brazil. Beetles were caught in ethanol baited ESALQ-84 vane traps in weekly collections from July 1995 until July 1997. In all, 87 species were trapped, 62 in the pine and 75 in the eucalypt stand. The most abundant beetle species in the pines were Hypothenemus eruditus, Xyleborinus gracilis, Cryptocarenus sp. and Xylosandrus retusus, while the most frequent were H. eruditus, Cryptocarenus sp., H. obscurus, Ambrosiodmus obliquus, and X. gracilis. In the eucalypt stand, H. eruditus, X. retusus, H. obscurus, X. ferrugineus and Microcorthylus minimus were the most abundant species, and H. eruditus, H. obscurus and M. minimus were the most frequently trapped. The majority of the species, regardless of the forest community, were most active between August (end of winter) and October (mid-spring). Significantly more H. eruditus, X. gracilis, Cryptocarenus sp., Corthylus obliquus, Hypothenemus bolivianus, A. obliquus, Sampsonius dampfi and Xyleborus affinis were trapped in the pine stand, while X. retusus, H. obscurus, X. ferrugineus, Xyleborinus linearicollis, Corthylus sp, and Corthylus convexicauda were caught in higher numbers in the eucalypt stand. Approximately 50% of the species trapped were found in both communities. Morisita's similarity index indicates the composition of the two communities is very similar, suggesting that most of the beetles are polyphagous. (C) 2001 Elsevier B.V. B.V. All rights reserved.

Genetic variation in growth traits and yield of rubber trees (Hevea brasiliensis) growing in the Brazilian state of São Paulo

Analysis of variance and covariance was preformed on growth traits (stem girth, bark thickness, total height gain and rubber yield) of 22 open-pollinated progenies of the rubber tree Hevea brasiliensis from an Asian Hevea collection introduced to Agronomic Institute (Instituto Agronômico, Campinas, São Paulo, Brazil; IAC) in 1952. This progeny trial was replicated at three sites in São Paulo state and it was found that at three years from sowing there was statistically significant variation for girth, bark thickness, height and rubber yield. An individual test sites, values of individual plant heritability for girth ranged from ĥ i 2 = 0.36 to ĥ i 2 = 0.89 whereas values for heritability for progeny means ranged from ĥ i 2 = 0.77 to ĥ i 2 = 0.87. These moderate and high heritabilities suggest that a combination of progeny and within-progeny selection would be effective at increasing girth in this population at individual sites. Across sites, values of individual-plant heritability for girth ranged from ĥ i 2 = 0.36 to ĥ i 2 = 0.47, whereas values for heritability of progeny means girth ranged from ĥ x̄ 2 = 0.77 to ĥ x̄ 2 = 0.87. There were high positive genetic correlations between increased girth and bark thickness suggesting that breeding aimed at increasing girth would also increase bark thickness and possibly height. Copyright by the Brazilian Society of Genetics.

Seasonal effects and antifungal activity from bark chemical constituents of Sterculia apetala (Malvaceae) at Pantanal of Miranda, Mato Grosso do Sul, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Triterpene benzoates from the bark of Picramnia teapensis (Simaroubaceae)

Two new benzoic acid esters of triterpene alcohols [lup-20 (29)-en-28-oic acid 3 alpha, 7 beta -dibenzoate and 3 alpha -hydroxy-lup-20(29)-en-28-ic acid 7 beta -benzoate] were isolated from the stem bark of Picramnia teapensis Tul. The structures of these compounds were established on the basis of spectral analyses. Other known compounds, beta -sitosterol, estigmasterol, lupeol and epilupeol, were identified in mixture by GC-MS. The triterpene esters have not shown in-vitro inhibitory effect on the growth of Leucoagaricus gongylophorus (Fisher), referred also as Leucocoprinus gongylophorus (Heim), syn Rozites gongylophora (Moller), the symbiotic fungus cultivated by the leaf-cutting ant Atta sexdens L.

Níveis de irrigação e de composto de lixo orgânico na formação de mudas cítricas em casa de vegetação

O presente trabalho visou a estudar o efeito da associação entre a irrigação e tipos de substratos na formação de mudas de laranjeira. O delineamento experimental utilizado foi o de blocos casualizados, com parcelas subdivididas, com quatro repetições, três níveis de irrigação e cinco tipos de substratos. Foram utilizados os seguintes substratos: 100% de casca de pínus; 80% de casca de pinus + 20% de composto de lixo orgânico; 60% de casca de pinus + 40% de composto de lixo orgânico; 20% de casca de pinus + 80% de composto de lixo orgânico, e 100% de composto de lixo orgânico. A irrigação por gotejamento foi feita com lâminas de 50%, 100% e 150% da evaporação do atmômetro modificado. A avaliação do desenvolvimento das plantas foi feita quinzenalmente, medindo-se o diâmetro do caule e a altura. Os resultados mostraram que as mudas de citrus apresentaram necessidade de água variável com os diferentes estádios de desenvolvimento e tipos de substratos, dos quais se destacou o substrato 3 (60% de casca de pinus e 40% de composto de lixo urbano), pois propiciou melhores condições para o desenvolvimento das raízes das plantas e também forneceu nutrientes, por meio da decomposição do material orgânico. A irrigação 3 (150% da evaporação do atmômetro) foi a que proporcionou o melhor desenvolvimento das mudas de laranjeira.

Occurrence of Quesada gigas on Schizolobium amazonicum trees in Maranhão and Pará States, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Caracterização de quatro grupos de jabuticabeira, nas condições de Jaboticabal-SP

O presente trabalho foi conduzido com o objetivo de avaliar as características morfológicas e físicas da planta e do fruto de jabuticabeiras, pertencentes à coleção da FCAV-UNESP, Câmpus de Jaboticabal-SP. A coleção conta com 160 plantas, das quais 40, que apresentavam frutificação no momento da seleção, foram agrupadas, preliminarmente, segundo características semelhantes, em quatro grupos denominados JAB 01, JAB 02, JAB 03 e JAB 04. Mediram-se nestes grupos a altura da planta, diâmetro do tronco a 20 cm do solo, diâmetro de copa, comprimento do entrenó e largura da folha. Os frutos, foram avaliados quanto a comprimento, largura, massa fresca da casca, da semente, da polpa e total, bem como o número de sementes por fruto. O delineamento utilizado foi o inteiramente casualisado, com 4 tratamentos, quatro grupos de plantas e 5 repetições, com 2 plantas por repetição. Os dados foram submetidos à análise de variância pelo teste (F) e as médias comparadas pelo teste de Tukey. Observou-se grande variabilidade nos grupos estudados. O JAB-04 revelou-se como o mais promissor para utilização em programas de melhoramento, pela precocidade de produção, baixo porte e maior rendimento em polpa, apesar de os frutos apresentarem menor tamanho em relação aos dos demais grupos.

Effect of liming on the mineral nutrition and yield of growing guava trees in a typic hapludox soil

High soil acidity influences the availability of mineral nutrients and increases that of toxic aluminium (Al), which has a jeopardizing effect on plant growth. The objective of this research was to evaluate the effects of soil liming on the development of guava (Psidium guajava L.) plants, on soil chemical characteristics, and on fruit yield. The experiment was carried out at the Bebedouro Citrus Experimental Station, state of São Paulo, Brazil, in a Typic Hapludox soil, from August 1999 to March 2003. The treatments consisted of limestone dose: D0 = zero; D1 = half dose; D2 = total dose; D3 = 1.5 times the dose, and D4 = 2 times the dose to raise the V value to 70%. The doses corresponded to zero, 1.85, 3.71, 5.56, and 7.41tha(-1) applied to the upper soil layer (0-30cm deep) before planting. The results showed that liming caused an improvement in the evaluated soil chemical characteristics up to a depth of 60cm in soil samples both in the line and between lines. The highest fruit yields were obtained when the base saturation reached a value of 55% in the line and 62% between the lines. Foliar levels of calcium (Ca) and magnesium (Mg) were 8.8 and 2.5gkg-1, respectively. The highest limestone dose maintained the soil base saturation (at the layer of 0-20cm) in the line close to 55% during at least 40 months after the incorporation of limestone.

Carbon-13 turnover in 'roxo de valinhos' fig trees

The aim of this study was to assess carbon-13 turnover in different organs of the fig tree, 'Roxo de Valinhos' cultivar. The experiment was carried out in an orchard at School of Agronomical Sciences, FCA/UNESP, Botucatu Campus, State of São Paulo, Brazil. The main photosynthetically active leaf was previously determined based on gas exchanges by means of an open portable photosynthesis system, IRGA. That leaf was placed in a chamber where the enriched gas injection occurred. The leaf enrichment time was 30 minutes. Treatments were constituted of seven fig trees removed from the soil after: 6; 24; 48; 72; 120; 168 and 360 hours of enrichment using (13)C, and their parts were sectioned into: apical bud, young leaves, adult leaves (photosynthetically active), lateral sprouts, fruits, and branch. The results allowed the establishment of the carbon-13 metabolism sequence in the studied parts: Young leaves > Fruits > Sprouts > Adult leaves > Apical bud > branch > Labeled leaf. 'Roxo de Valinhos' fig trees, had (13)C turnover of 24 hours and carbon-13 half-time shorter than 11 hours.

Intensidade do mal das folhas em plantas jovens e adultas de seis clones de seringueira na região do Vale do Ribeira: South American leaf blight intensity evaluated in six clones of young and adult rubber trees in the Vale do Ribeira region, São Paulo state, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Dominance of legume trees alters nutrient relations in mixed species forest restoration plantings within seven years

Failures in reforestation are often attributed to nutrient limitation for tree growth. We compared tree performance and nitrogen and phosphorus relations in adjacent mixed-species plantings of contrasting composition, established for forest restoration on Ultisol soil, originally covered by tropical semi-deciduous Atlantic Forest in Southeast Brazil. Nutrient relations of four tree species occurring in both planting mixtures were compared between a legume-dominated, species-poor direct seeding mixture of early-successional species ("legume mixture"), and a species-diverse, legume-poor mixture of all successional groups ("diverse mixture"). After 7 years, the legume mixture had 6-fold higher abundance of N(2)-fixing trees, 177% higher total tree basal area, 22% lower litter C/N, six-fold higher in situ soil resin-nitrate, and 40% lower in situ soil resin-P, compared to the diverse mixture. In the legume mixture, non-N(2)-fixing legume Schizolobium parahyba (Fabaceae-Caesalpinioideae) had significantly lower proportional N resorption, and both naturally regenerating non-legume trees had significantly higher leaf N concentrations, and higher proportional P resorption, than in the diverse mixture. This demonstrate forms of plastic adjustment in all three non-N(2)-fixing species to diverged nutrient relations between mixtures. By contrast, leaf nutrient relations in N(2)-fixing Enterolobium contortisiliquum (Fabaceae-Mimosoideae) did not respond to planting mixtures. Rapid N accumulation in the legume mixture caused excess soil nitrification over nitrate immobilization and tighter P recycling compared with the diverse mixture. The legume mixture succeeded in accelerating tree growth and canopy closure, but may imply periods of N losses and possibly P limitation. Incorporation of species with efficient nitrate uptake and P mobilization from resistant soil pools offers potential to optimize these tradeoffs.

Antioxidant activity of Maytenus ilicifolia root bark

Maytenus ilicifolia is an important plant with potential on cancer treatment and has been largely used in Brazil and other countries. We have evaluated the crude ethanolic extract of M. ilicifolia as a potential antioxidant source using an assay based on the bleaching of the radical monocation 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(center dot+)) and by HOCl scavenger capacity. Trolox and uric acid were used as positive controls. The results indicated M. ilicifolia root bark as a great source of antioxidants based on its potential as scavenger of radicals. (c) 2006 Elsevier B.V. All rights reserved.

Antimicrobial, Cytotoxic and Antioxidant Activities and Determination of the Total Tannin Content of Bark Extracts Endopleura uchi

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The Styracaceae

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)