Germination characteristics of Syngonanthusseeds (Eriocaulaceae) incampos rupestresvegetation in south-eastern Brazil

Abstract

The present study evaluated the size and germination characteristics of seeds of seven species of Syngonanthus (distributed among four sections) that occur in different microhabitats in campos rupestres vegetation in Minas Gerais State, to determine if (1) the germination responses of the various species characterize a single germination pattern for the genus; and (2) there is a correlation between the germination characteristics and the geographic distribution as well as the microhabitat of the different species. The experiments were undertaken with recently collected seeds exposed to a 12-h photoperiod and continuous darkness, at constant temperatures of 10-408C (at intervals of 58C) in germination chambers. The results indicated the existence of a pattern of reduced seed size and light requirements for germination within the genus. The geographic distribution of different species of the genus cannot be explained by the responses of seed germination to different temperatures, but suggests some relationship to their edaphic microhabitats. Therefore, germination characteristics of the populations studied may have been selected to colonize specific environments at different soil water conditions.

Harvest times of Comanthera elegans, a worldwide traded Brazilian species of everlasting flower: implications on seed production, germination, and on species management

“…These results indicate that the germination of C. elegans seeds varies with the harvest date, the collection site, and with each annual flowering. As phenology varies among regions (Williams-Linera and Meave 2002), the differences between the germination rates of our study and the results reported by Nunes et al (2008b) and Oliveira and Garcia (2005) could be associated, among other factors, with annual climatic variations, which besides influencing the beginning and duration of harvests, can also influence the physiological status of propagules, such as the period of seed maturation (Taiz and Zeiger 2010); or to climatic and/ or edaphic microconditions of the site where the seedproducing plants developed (Oliveira and Garcia 2011). In C. elegantula, a species with similar life-forms and lifehistories to C. elegans, and which is collected at the same time as it, there is a marked association between phenological parameters, rainfall and soil water availability (Bedê 2006).…”

Diversity of germination strategies and seed dormancy in herbaceous species of campo rupestre grasslands

“…As an additional treatment, seeds were also exposed to fluctuating temperatures between 15°C and 25°C and between 20°C and 30°C, based on a 12‐h photoperiod (with the highest temperature corresponding to daytime). Seeds were exposed to 27 μmol m −2 s −1 light incidence, because small‐sized seeds of campos rupestres herbs are light demanding (Abreu & Garcia ; Oliveira & Garcia ; Mota & Garcia ; Silveira et al . ).…”

Expression of Enzymes During the Germination of Seeds in Endangered Cerrado Species

“…The germination test was conducted with four replications of 100 seeds, with sowing in germination blotter paper soaked with distilled water in a proportion of 2.5 times the weight of the paper and placed in gerbox-type plastic boxes. The seeds remained in BOD during 35 days in alternating temperature of 25 °C/16 hours in the presence of light and 15 °C/8 hours in the dark for the species Comanthera elegans according to Pereira et al 2014and to Comanthera bisulcata was 20 °C/16 hours in the presence of light and 15 °C/8 hours in the dark according to Oliveira and Garcia (2011). The results were expressed as mean percentage of normal seedlings.…”