Antonio Nascim Kalil Filho

IN VITRO MULTIPLICATION OF Swietenia macrophylla KING (MELIACEAE) FROM JUVENILE SHOOTS

Big-leaf mahogany (Swietenia macrophylla King) is an important species for timber production that is considered the most valuable in the world. For this reason its exploitation is indiscriminate and leads this species to the risk of extinction. Moreover, mahogany is difficult to regenerate naturally and, when used in reforestation programs, plants are severely damaged by the shoot-borer (Hypsipyla grandella Zellar). This work aimed at developing the multiplication stage of micropropagation of Swietenia macrophylla King using juvenile material. After desinfestation, seeds were germinated in MS solid culture medium. Shoot formation from seeds occurred during five months, giving 5.54 nodal segments per seed. These explants were excised, each containing one axillary bud, and transferred on multiplication media. Four experiments with cytokinins were conducted, using media supplemented with 6-benzylaminopurine (BAP) (2.5 to 50.0 µM), 2isopentenyladenine (2-iP) (0; 1.1 to 8.8 µM), combinations of BAP (0; 2.5 to 50.0 µM) and 2-iP (2.2 µM). For the first treatments the basal culture medium was MS medium and in the last one MS and QL media were used in separate experiments. When BAP was tested alone, the maximum point of multiplication rate average was obtained on medium containing 23.61 µM, while 2-iP did not induce bud multiplication. On QL culture medium supplemented with the combinations of BAP (0; 2.5; 5.0; 10.0 e 20.0 µM ) and 2-iP (2.2 µM), there was no multiplication. The maximum point of multiplication rate average was 5.7 µM, obtained when the MS culture medium was supplemented with 18.51 µM BAP and 2.2 µM 2-iP.

Inoculation methods, aggressiveness of isolates and resistance of peach palm progenies to Phytophthora palmivora

Podridao da Base do Estipe (PBE) causada por Phytophthora palmivora e a principal doenca da pupunheira no viveiro e no campo. O objetivo deste trabalho foi: a) determinar o metodo mais apropriado de inoculacao de P. palmivora em pupunheira; b) avaliar a agressividade de isolados de P. palmivora; c) avaliar a resistencia de progenies de pupunheira a P. palmivora. Os experimentos foram conduzidos na Embrapa Florestas no periodo de marco de 2011 a marco de 2012. Foi desenvolvida uma escala descritiva de notas para avaliar a severidade da PBE da pupunheira. A severidade da doenca foi avaliada aos 7, 14, 21 e 28 dias apos a inoculacao. Concluiu-se que: a) O metodo de injecao na base do estipe foi o mais efetivo para a inoculacao de P. palmivora; b) Os isolados de P. palmivora: SA-5, SA- 9, SA-10, SA-11, SA-14, SA-15, SA-16, SA-30 e SA-31 foram os mais agressivos; e c) As progenies de pupunheiras T2, T4, T7, T9 e T15 mostraram resistencia a P. palmivora.

GENE DIVERSITY IN GREVILLEA POPULATIONS INTRODUCED IN BRAZIL AND ITS IMPLICATION ON MANAGEMENT OF GENETIC RESOURCES

http://dx.doi.org/10.1590/1806-90882018000200005 ABSTRACT – We describe isoenzymes variability in six populations of Grevillea robusta from a provenances and progenies test established in a randomized block design with five plants per replication in Southern Brazil. The population genetic structure was examined by using biochemical markers in 5-year old trees, specifically at MDH-3, PGM-2, DIA-2, PO-1, PO-2, SOD-1, and SKDH-1 loci. The northern provenances (Rathdowney and Woodenbong) showed a strong divergence in relation to the average of provenances when alleles per locus (Ap), allele richness (Rs), Nei’s gene diversity (H), and inbreeding coefficient (f) were considered. Inbreeding in varying degrees was detected. The commercial control showed the highest inbreeding coefficient, (f = 0.4448), whereas the provenance average was f = 0.2306, possibly due to insufficient sampling of populations in their origin (Australia). Despite its restricted natural range, a positive correlation between genetic divergence and geographic distance among original populations was detected. Genetic distance and cluster analyses based on the Bayesian model revealed three distinct provenance groups: 1) Rathdowney-QLD and Woodenbong-QLD; 2) Paddy’s Flat-NSW; and 3) Mann River-NSW, Boyd River-NSW and the commercial control (material used in Brazil). The grouping of the control to both Mann River-NSW and Boyd River-NSW provenances suggests that the northern provenances have the highest potential for genetic improvement of wood productivity in Brazil, due to their high genetic diversity and low inbreeding coefficient.

EPICORMIC SHOOTS INDUCTION AND ROOTING CUTTINGS OF Calophyllum brasiliense

Calophyllum brasiliense apresenta ampla distribuicao natural no Brasil e seu crescimento monopodial, fuste retilineo e madeira moderadamente densa tem atraido o interesse da industria madeireira nas ultimas decadas. Entretanto, a carencia em metodos eficientes de resgate e propagacao vegetativa de material adulto tem sido um fator limitante na selecao de genotipos superiores em programas de melhoramento da especie. Assim, objetivou-se avaliar metodos de inducao de brotacoes epicormicas e o enraizamento de estacas em arvores de Calophyllum brasiliense com 14 anos de idade. Para tanto, tres metodos de inducao de brotacoes epicormicas foram implantados: decepa, anelamento e semianelamento. Avaliou-se o numero de brotos produzidos e a porcentagem de matrizes brotadas aos 6, 12 e 15 meses apos a instalacao do experimento. Com as brotacoes resultantes, foram instalados tres experimentos de estaquia, comparando o enraizamento adventicio entre as diferentes matrizes e metodos de inducao de brotacoes epicormicas. Os resultados demonstraram a viabilidade do resgate vegetativo de Calophyllum brasiliense por estaquia utilizando brotacoes epicormicas induzidas por decepa e anelamento do tronco. Em contrapartida, o semianelamento nao foi eficiente na inducao de brotacoes epicormicas. Em relacao ao enraizamento adventicio, a tecnica de inducao nao influenciou o enraizamento de estacas, apresentando variacao entre as diferentes matrizes