Edison Bisognin Cantarelli

Quantificação das perdas no desenvolvimento de Pinus taeda após o ataque de formigas cortadeiras.

In this study, the main purpose was to quantify the diameter, height and productivity index losses in initial development in Pinus taeda seedlings in stands in Argentine, after leaf cutting ants attack. The treatments were: T1 = control without attack; T2 = attacked by ants; and T3 = sequential artificial deneedling. The three development stages of the plants in two distinct slopes were also evaluated. The results allow concluding that there is a significant reduction in Pinus taeda development when attacked by leaf cutting ants during the first 24 months. In the artificially deneedled plants, there was a significant reduction related to the ones deneedled by the ants, for all the analyzed variables.

Plano de amostragem de Acromyrmex spp. (Hymenoptera: Formicidae) em áreas de pré-plantio de Pinus spp

A study was conducted to elaborate a sampling plan to leaf cutting ants in forest pre-planting areas, at Bosques del Plata company, located in Santo Tome, Corrientes province, Argentine. The research had as object of study the spatial distribution of Acromyrmex nests in Pinus spp. pre-planting areas to determine the adequate plots size and to estimate the sampling intensity to this genus of ants. It was concluded that the Acromyrmex spp. nests spatial distribution in Corrientes-Argentine, adjusts to the randomized model, the adequate plot size to sample the nests density (hole. ha-1) is 700m2 (10x70m) and the adequate sampling intensity is 10.5% for a predicted error of 24%.

Efeito do manejo de plantas daninhas no desenvolvimento inicial de Pinus taeda em várzeas na Argentina

Realizou-se um estudo sobre o efeito de cobertura e periodos de manejo de plantas daninhas em plantios no ano de 1999 de Pinus taeda, localizados na Provincia de Corrientes, Argentina. Em razao das caracteristicas da area, varzeas, foram construidos camalhoes de 1,80 m de largura por 0,60 m de altura para o plantio das mudas e, a seguir, instaladas parcelas com tres fileiras de 12 plantas em cada uma no espacamento de 1,75 m entre as mudas e 4,0 m entre o centro dos camalhoes. Foram medidas somente as 10 plantas do camalhao central, com o objetivo de avaliar o efeito de diferentes modalidades e intensidades de manejo de plantas daninhas na sobrevivencia (%), no desenvolvimento inicial em altura (cm), no diâmetro do colo (cm) e no fator de produtividade (cm3) das mudas de Pinus taeda. Avaliaram-se as modalidades de controle: controle quimico na linha do plantio (camalhao) e controle quimico em area total sendo avaliados por dois periodos: um ano e dois anos de controle, tendo ainda uma testemunha, sem nenhum controle. O delineamento estatistico do experimento foi em blocos ao acaso, com tres repeticoes. Diferencas significativas foram obtidas entre os tratamentos de controle quimico em relacao ao sem controle. Os resultados levaram a conclusao de que e benefico o controle por dois periodos e que nao houve diferenca quanto as modalidades de controle (camalhao e area total). As mudas de Pinus taeda foram submetidas ao teste de Tukey para analise da sobrevivencia e nao apresentaram diferenca significativa a 5% de probabilidade de erro nas medias.

FENOLOGIA, MORFOLOGIA E ANÁLISE DE SEMENTES DE Cordia trichotoma (Vell.) Arráb. ex Steud.

On this paper, the phenology and morphology as well as physical and physiological tests were carried out with seeds of Cordia trichotoma (Vell.) Arrab. ex Steud. The collection of botanical material and phenological observations were performed on five selected trees located in Frederico Westphalen, Rio Grande do Sul state, from March 2007 to March 2010. The work was conducted under laboratory and greenhouse conditions at the Universidade Federal de Santa Maria, Rio Grande do Sul state. For three years, the bloom was most intense from March to April and the fruiting from May to June. The species has inflorescence, paniculate, consisting of small white colored and hermaphrodite flowers. The fruit is simple, drupaceous, terminated by the corolla tube and by the persistent calyx. The seed is cylindrical, ellipsoidal, pale brown exalbuminous, cotyledonary embryo with baseline, and invaginated plicate cotyledons, trapped around the root hypocotyl axis. The germination is epigeal and the seedling phanerocotyledonal. Seeds are recalcitrant and the average number was 24,591 per kilogram, the seed moisture content was 51 %, the germination was 40 % and the emergence was 29 %. The germination index is oscillating comparing the results of this paper to others, probably due to seed quality, which varies according to each parent tree and its micro-habitat. Therefore, there is importance in the selection of individuals, noticing the features that will bring genetic and physiological representation of the species, thus increasing the homogeneity of the seed lot.

Crescimento em viveiro de mudas de Schizolobium parahyba (Vell.) S. F. Blake. submetidas a níveis de sombreamento

The study of the growth and development of a plant under different environmental conditions offers the researcher a good clue as to which are the best conditions to grow a particular species. The main objective was to evaluate the initial growth, for up to 80 days, for of Schizolobium parahyba (guapuruvu) seedlings submitted to the shading levels: 0% (full sunshine), 30%, 50% and 70% shading. The results demonstrate that the shading interfered positively in the growth in height of the seedlings, even at the greatest levels, and did not cause damage to the plants, which was proven by the lack of differences in the variables: dry matter, lap diameter and number of pairs of leaves. The production of quality seedlings is favorable up to the 45th day of submission to shading, after which seedlings should be transplanted.

Fenologia, morfologia e análise de sementes de Apuleia leiocarpa (Vogel) J. F. Macbr.

Com o objetivo de agregar conhecimentos em relacao a Apuleia leiocarpa (Vogel) J. F. Macbr., analisou-se sua epoca de floracao e frutificacao, a morfologia de frutos, sementes, germinacao, plântula e muda, como tambem caracteristicas f isicas, germinacao e emergencia de sementes de diferentes arvores matrizes. A partir da selecao de 20 arvores matrizes, foram realizadas observacoes mensalmente, a fim de averiguar a presenca de flores e frutos. Apos a maturacao dos frutos, estes foram coletados, suas sementes extraidas, beneficiadas e separadas por matriz, de onde foram retiradas amostras para determinacao do peso, teor de agua, testes germinativos e de emerg encia em condicoes de laboratorio e viveiro. Exemplares de frutos e sementes foram armazenados em alcool 70 %, para posterior descricao morfologica. A maior presenca de flores de grapia ocorreu de setembro a outubro e de frutos, de janeiro a marco, havendo variacoes em relacao a epoca e a frequencia de arvores matrizes nas fenofases, assim como a quantidade estimada de frutos e sementes presentes em cada ano. Morfologicamente, o fruto e simples, vagem seca e indeiscente, com 1 a 2 sementes cada, sendo estas de coloracao castanha, com cicatriz linear visivel, rafe pouco desenvolvida e micropila proxima ao hilo. Internamente, a semente e albuminosa, com embriao axial, espatulado, ocupando ¾ da regiao interna, com cotiledones foliaceos e grandes. A germinacao e epigea e a plântula fanerocotiledonar. O comprimento dos frutos variou de 1,45 a 3,01 cm, a largura de 1,20 a 2,07 cm e a espessura de 0,20 a 0,30 cm. Para as sementes, 1,2 a 2,1 cm de comprimento, 0,6 a 0,95 cm de largura e 0,1 a 0,2 cm de espessura. Houve diferencas entre arvores matrizes para os testes f isicos e fisiologicos, onde o numero de sementes por quilograma variou de 8.713 a 11.197, o grau de umidade de 12,43 a 27,97 %, a germinacao de 13 a 96 % e a emergencia de 26 a 88 %. Concluiu-se que sementes provenientes de individuos de uma mesma populacao possuem variacoes expressivas quanto as caracteristicas fisicas e fisiologicas, seja em funcao do ambiente, fator gen etico ou do micro-habitat. Assim, apesar de proporcionar melhor representatividade genetica, reduzem a homogeneidade do lote de sementes.

REGISTRO DE NOVAS ESPÉCIES DE FORMIGAS (HYMENOPTERA: FORMICIDAE) NO ESTADO DO RIO GRANDE DO SUL

This study aimed to report the registration of new ant species in Rio Grande do Sul state and thus to contribute to the knowledge about the ant fauna (Myrmecofauna). Collections were made in four different environments, namely, native forest, eucalyptus plantations, agricultural plantation and exotic pasture. We used the mini-Winkler method of extraction to collect the ants. We removed 1 square meter (1m²) of litter, sifted it and packed it in mini-Winkler extractors to obtain the fauna. We collected 108 species, which represent 31 genera, 18 tribes and 8 subfamilies. The native forest presented 90 collected species, the eucalyptus plantation presented 65 species, and the agricultural plantation and the exotic pasture presented 20 species each. We have registered for the first time the following species in the state of Rio Grande do Sul: Dorymyrmex thoracicus (Dolichoderinae), Camponotus arboreus, Camponotus melanoticus (Formicinae), Apterostigma madidiense, Apterostigma sp. pilosumcomplex, Cyphomyrmex major, Cyphomyrmex vorticis, Wasmannia rochai, Cephalotes pusillus, Strumigenys (Pyramica) rugithorax, Strumigenys cosmotela, Strumigenys silvestrii, Pheidole aper, Pheidole heyeri, Pheidole rugatula, Pheidole siggilata, Pheidole senilis,Pheidole sospes, Megalomyrmex pusillus (Myrmicinae), and Pachycondyla ferruginea (Ponerinae).

DIVERSIDADE DE FORMIGAS (HYMENOPTERA: FORMICIDAE) DA SERRAPILHEIRA EM DIFERENTES SISTEMAS DE USO DO SOLO

Litter ant species found in four sites located in northwestern Rio Grande do Sul state were listed in this study to verify the impact of human activities conducted in rural areas. The method used for the collection of litter ants was the Winkler extractor. We collected 6,300 specimens belonging to eight subfamilies, 18 tribes, 31 genera and 108 species. Native forest presented the highest richness observed with 90 species collected, followed by 65 eucalyptus species, and agriculture and pasture with 20 exotic species each. Margalef’s diversity index was 11.21 for area with native forest, 8.37 for Eucalyptus, 3.48 for agriculture, and 2.71 in exotic pasture area. The Shannon’s diversity indices obtained were 2.89, 3.15, 2.43 and 1.98 and equitability indices of 0.64, 0.75, 0.84 and 0.66 for areas with native forest, eucalyptus, agriculture and exotic pasture, respectively. The highest diversity index for the Eucalyptus area may be due to the age of the forest (28 years) and the fact that it has not been managed as well as due to the presence of understory of native species, forming a continuous canopy and thick litter layer. On the other hand, since the native forest has suffered human interventions, it has a lower Shannon’s diversity index compared to the Eucalyptus area.

Ocorrência de Phaops thunbergi (Coleoptera: Curculionidae) em Acacia mearnsii De Wild

The occurrence of Phaops thunbergi (Dalman, 1823) (Coleoptera: Curculionidae) attacking plants of black wattle (Acacia mearnsii De Wild.) in Brazil was observed. It was recorded for the first time in Butia, State of Rio Grande do Sul (30o13’56.1” South, 51o58’34.6” West) in January 2004.

OCORRÊNCIA DE Glycaspis brimblecombei (Moore, 1964) (Hemiptera:Psyllidae) EM Eucalyptus spp. NO RIO GRANDE DO SUL, BRASIL

January, 2005: occurrence of Glycaspis brimblecombei (Moore, 1964) (Hemiptera: Psyllidae) in species of Eucalyptus spp. Was verified for the first time in the state of Rio Grande do Sul, Brazil. Observations occurred in the cites of Butia, Cacapava do Sul and Santa Maria.