Overcoming seed dormancy in visgueiro-of-the-igapó (Parkia discolor)

This study aimed to evaluate the effects of pregerminative mechanical scarification treatments, as well as heat pre-treatments on the germination of visgueiro-of-the-igapó (Parkia discolor Spruce ex Benth.) seeds. The first experiment, with a completely randomized design and four repetitions, evaluated these pre-treatments: control (without pre-treatment); clipping at the distal portion; clipping at the proximal portion (hilum); clipping at the proximal and distal portions; scraping at the distal portion; scraping at the proximal portion; scraping at the proximal and distal portions; perforation of the husk with a soldering-iron; and perforation by pyrography. In the second experiment, with a completely randomized design and factorial 2 (heat: dry and wet) x 4 (temperature: 40ºC, 50ºC, 60ºC and 70ºC) x 5 (period of conditioning: 6, 16, 24, 30 and 48 hours), with three repetitions. The clipping or scraping of the seeds in the proximal portion and proximal and distal portions allowed faster imbibition of the seeds (143-163% in three days and half), and consequently, better germination (98-100% in four days), germination speed rate (1,351-1,460) and average time of germination (3 days). The pre-treatment with heat (wet and dry), under different temperatures and different conditioning periods did not overcome the dormancy of P. discolor seeds.O presente trabalho teve como objetivo avaliar os efeitos da aplicação de tratamentos pré-germinativos de escarificação mecânica, bem como pré-tratamentos com calor, sobre a germinação de sementes de visgueiro-do-igapó (Parkia discolor Spruce ex Benth.). No primeiro experimento, sob delineamento inteiramente ao acaso, com quatro repetições, foram avaliados os pré-tratamentostestemunha (sem pré-tratamento); desponte no lado distal; desponte no lado proximal; desponte nos lados distal e proximal; lixamento no lado distal; lixamento no lado proximal; lixamento nos lados distal e proximal; perfuração do tegumento com ferro-de-solda; e perfuração com pirógrafo. No segundo experimento, foi adotado o delineamento inteiramente casualizado, em esquema fatorial 2 (calorseco e úmido) x 4 (temperatura40ºC, 50ºC, 60ºC e 70ºC) x 5 (período de condicionamento6, 16, 24, 30 e 48 horas), com três repetições. O desponte ou lixamento das sementes na porção proximal e porções proximal e distal possibilitaram uma embebição mais rápida (143-163%, aos três dias e meio) e, conseqüentemente, melhores resultados de germinação (98-100%, aos quatro dias), do índice de velocidade de germinação (1,351-1,460) e do tempo médio de germinação (3 dias). Os pré-tratamentos com calor (úmido e seco), sob diferentes temperaturas, e por vários períodos de condicionamento não superaram a dormência de sementes de P. discolor

Further new endemic taxa of Cunoniaceae from New Caledonia

A description, illustration, distribution map and conservation assessment are given for each of three new species of Cunoniaceae from New Caledonia and plants endemic to the same localities from other genera are mentioned. Cunonia bopopensis Pillon & H. C. Hopkins is known from forest on ultramafic soils at high elevation on Mt Tchingou. This massif offers ecological conditions markedly different from those of its surroundings, which may explain the occurrence of several micro-endemics on this mountain. Some specimens of C. bopopensis were previously identified as C. bernieri Guillaumin but the type of the latter is probably a hybrid and this name is now considered doubtful. Geissois belema Pillon & H. C. Hopkins is endemic to Ile Art in the Belep archipelago, where it occurs in forest on ultramafic soils; it is the only species of Geissois known from Ile Art. Pancheria xaragurensis H. C. Hopkins & Pillon is found largely on the little-explored Forgotten Coast (“Côte Oubliée”) of south-eastern Grande Terre, generally in maquis along streams and in river beds at low elevation on ultramafic substrate. Morphological and ecological variation in the widespread taxa Geissois pruinosa Brongn. & Gris and Weinmannia dichotoma Brongn. & Gris are discussed and the combinations G. pruinosa var. intermedia (Vieill. ex Pamp.) H. C. Hopkins & Pillon and W. dichotoma var. monticola (Däniker) H. C. Hopkins & Pillon are published to accommodate some of this variability

Kermadecia brinoniae (Proteaceae: Macadamieae), a new species from New Caledonia previously confused with K. elliptica

Kermadecia brinoniae H.C. Hopkins & Pillon (Proteaceae), which occurs in southern New Caledonia, principally on ultramafic substrates, is described and illustrated. Material of this species was previously included in Kermadecia elliptica Brongn. & Gris. An amended description is given for the latter and a lectotype designated. These two species differ in the prominence of the venation on the lower leaf surface and in their ecology. Kermadecia brinoniae, like other species of Proteaceae growing on ultramafic substrates of New Caledonia, has a relatively high content of manganese in its leaves. A revised key to the species of Kermadecia Brongn. & Gris is provided as well as notes on the morphology of the pollen presenter

Flore de la Nouvelle-Calédonie : 26. Cunoniaceae

La flore de Nouvelle-Calédonie est mondialement connue pour son exceptionnelle richesse avec quelque 3 371 espèces indigènes de plantes vasculaires dont les 3/4 sont endémiques du territoire. L'originalité de cette flore est remarquable, tant aux niveaux taxonomiques supérieurs (une centaine de genres et trois familles endémiques) que par la concentration de lignées primitives ou inhabituelles tel un conifère parasite, ou de plantes accumulatrices de métaux lourds. Des espèces restent encore à décrire et des programmes de recherche sont nécessaires pour mieux comprendre l'origine de cette diversité et contribuer à sa préservation. Ce nouvel ouvrage de la Flore de Nouvelle-Calédonie, publié conjointement par le Muséum national d'Histoire naturelle et l'Institut de Recherche pour le Développement, est une monographie sans précédent des Cunoniaceae de Nouvelle-Calédonie. Cette famille de près de 350 espèces, de répartition essentiellement australe, est particulièrement bien représentée sur le Territoire, où ont été recensées 91 espèces, toutes endémiques, réparties en sept genres : Codia, Cunonia, Geissois, Hooglandia, Pancheria, Spiraeanthemum, Weinmannia. Après une présentation générale de la famille, la description de chaque genre et des espèces qu'il comporte est accompagnée de clés d’identification nombreuses et illustrées, de cartes de répartition, de dessins au trait. L'ensemble est enrichi par de nombreuses photographies. Aussi détaillée qu'attractive, cette flore restera la référence internationale sur les Cunoniaceae de Nouvelle-Calédonie pendant de nombreuses années