Diversidade genética de populações naturais de pariparoba [Pothomorphe umbellata (L. ) Miq.] por RAPD / Genetic diversity of natural populations of pariparoba [Pothomorphe umbellata (L. ) Miq.] according to RAPD analysis

O objetivo desse trabalho foi analisar a estrutura genética de populações de Pothomorphe umbellata (L.) Miq. com base em polimorfismos moleculares do tipo RAPD. Foram analisadas quatro populações naturais do estado de São Paulo (Jacareí, Jundiaí, Piquete e Ubatuba) e uma população do Paraná (Adrianópolis). Foram identificados 25 locos polimórficos (96,15%). Elevados índices de diversidade genética foram observados dentro das populações (Hs = 0,2220). Verificou-se que 65,33% da variabilidade genética total encontra-se dentro das populações e 34,67% entre as populações; índices estes, obtidos a partir do cálculo da divergência genética (G ST = 0,3467). Os resultados sugerem que essas populações possuem níveis elevados de variabilidade genética, a qual pode ser fortemente impactada pela ação humana.

The aim of this study was to analyze the genetic structure of populations of Pothomorphe umbellata (L.) Miq. based on RAPD molecular polymorphisms. Analysis included four natural populations from São Paulo State (Jacareí, Jundiaí, Piquete, Ubatuba) and one population from Paraná State (Adrianópolis). Twenty-five polymorphic loci (96.15%) were identified. There were high levels of genetic diversity within populations (Hs = 0.2220). Of the total genetic variability, 65.33% is within populations and 34.67% among populations (G ST = 0.3467). Results suggest that these populations have high levels of genetic variability, which can be strongly impacted by human action.

Propagação vegetativa de espécies silvestres do gênero Piper, com potencial para uso como porta enxertos em pimenta-do-reino (Piper nigrun) / Vegetative propagation of wild species of the genus Piper, with potential for use as rootstocks in black pepper (Piper nigrun)

O estabelecimento de espécies usadas como porta-enxerto, importantes na olericultura, podem ser multiplicadas por meio da estaquia com auxílio de fitorreguladores. Objetivou-se com este trabalho avaliar a influência do AIB no estabelecimento de espécies nativas do gênero Piper com potencial de uso como porta-enxerto de Piper nigrum. Estacas de P. Arboreum, P. amplum e P. sp foram submetidas a diferentes dosagens de AIB (0, 2000, 4000, 6000 e 8000 mg.L-1) e mantidas em estufa agrícola com irrigação intermitente com temperatura e umidade controlados. O delineamento experimental utilizado foi inteiramente casualizado em esquema fatorial 3x5 (3 espécies de Piper x 5 dosagens de AIB) e composto por 3 repetições por tratamento, sendo cada parcela composta por 10 estacas. A avaliação foi realizada aos 45 dias de transplantio e as variáveis analisadas foram: índice de sobrevivência, número médio de folhas, número médio de brotos e comprimento médio do maior broto. A espécie Piper arboreum apresentou bons resultados referentes ao crescimento da parte aérea independentemente da concentração de AIB empregada.

The establishment of species used as rootstock, which are important in horticulture crop scan may be multiplied, with the aid of growth regulators, by cutting. The objective of this study was to evaluate the influence of IBA on the establishment of native species of the genus Piper with potential use as rootstock of Piper nigrum. Cuttings of P. arboreum, P. amplum and P. sp were treated with different concentrations of IBA (0 ,2000, 4000, 6000 and 8000mg.L-1) and maintained in a greenhouse with intermittent irrigation, with the temperature and humidity controlled. The experimental design was completely randomized in a factorial 3x5 plan (3 Piper species x5 doses of IBA) and comprising of three repetitions per treatment, each plot consisting of 10 cuttings. The evaluation was performed at 45 days of transplanting and the analyzed variables were: survival rate, the number of leaves, the number of shoots and the length of the largest shoot. The Piper arboretum species showed the best growth results for the aerial part independent of the IBA concentration used.

Verhuellia is a segregate lineage in Piperaceae: more evidence from flower, fruit and pollen morphology, anatomy and development.

BACKGROUND AND AIMS: The perianthless Piperales, i.e. Saururaceae and Piperaceae, have simple reduced flowers strikingly different from the other families of the order (e.g. Aristolochiaceae). Recent molecular phylogenies proved Verhuellia to be the first branch in Piperaceae, making it a promising subject to study the detailed structure and development of the flowers. Based on recently collected material, the first detailed study since 1872 was conducted with respect to morphology, anatomy and development of the inflorescence, pollen ultrastructure and fruit anatomy. METHODS: Original scanning electron microscopy (SEM), transmission electron microscopy (TEM) and light microscopy (LM) observations on Verhuellia lunaria were compared with those of Piperaceae, Saururaceae and fossils. KEY RESULTS: The inflorescence is an indeterminate spike with sessile flowers, each in the axil of a bract, developing in acropetal, helical succession. Flowers consist of two (occasionally three) stamens with basifixed tetrasporangiate anthers and latrorse dehiscence by a longitudinal slit. The gynoecium lacks a style but has 3-4 stigma branches and a single, basal orthotropous and unitegmic ovule. The fruit is a drupe with large multicellular epidermal protuberances. The pollen is very small, inaperturate and areolate, with hemispherical microechinate exine elements. CONCLUSIONS: Despite the superficial similarities with different genera of Piperaceae and Saururaceae, the segregate position of Verhuellia revealed by molecular phylogenetics is supported by morphological, developmental and anatomical data presented here. Unitegmic ovules and inaperturate pollen, which are synapomorphies for the genus Peperomia, are also present in Verhuellia.