Gynerium

Abstract: Gynerium was traditionally classified in the reed tribe Arundineae in the Arundinoideae, but recent molecular studies strongly support its affinities with the Panicoideae + Centothecoideae clade. A new tribe, the Gynerieae, is described to accommodate Gynerium.

Abstract: To reduce costs associated to ex vitro adaptation of arrow cane (Gynerium sagitatum Aubl.) plants Cv “Criolla”, the effect of three substrate mixes (Peat, peat + river sand and peat + rice husk) on survival, plant height and substrate associated plant cost were evaluated. Plants were micropropagated in semisolid MS medium supplied with 0,5 mg L-1 BAP. After medium removal, plants were transferred on 72-plug plastic trays filled with the respective substrate treatment. Trays were covered with translucent plastic covers during three days. Thereafter, plants were maintained in a 50% light shade house, fog irrigated twice a day for 1 minute each during 8 weeks. Treatments were distributed with a block randomized design. Data were analyzed with ANOVA and means were separated with Tukey´s mean separation test. Results allowed to evidence that peat + sand resulted in significant increase in survival, plant height and >35 decrease in substrate associated plant cost during adaptation to ex vitro conditions.

Abstract: Summary. Gynerium sagittatum (Aubl.) P. Beauv. is a widespread neotropical reed-like grass and a distinctive species of river banks. In early taxonomic literature it was described several times in different genera and as a result of this has acquired a lengthy synonymy. Recent findings indicate that Gynerium is highly variable in the western parts of South America, producing morphologically and ecologically distinct forms. We have studied the variation of Gynerium over all of its range, using field observations and herbarium surveys. Herbarium specimens were mostly of poor quality and appeared to be of limited value in studies of variation. Some botanists have considered Gynerium to be a single species, while others have suggested it is a species complex. We have adopted the former approach and have recognized two new varieties, described here, in the hope that they will provide a guide for future studies. A validation of the typification for Gynerium sagittatum is also provided.