Seed germination and seedling emergence of the invasive exotic species, Clausena excavata

Abstract

The aims of this study were to evaluate the effects of light and temperature on seed germination and the effect of light on seedling emergence of Clausena excavata, an invasive exotic species. Seeds were incubated at constant temperatures (10 to 40 ºC), under continuous white light and darkness. Seedling emergence was evaluated under full sun and canopy shade. There was no significant difference between seeds germinated in the presence or absence of light at temperatures between 20 and 35 ºC. Seeds maintained at 20 ºC germinated more slowly than other temperatures. Independent of temperature, seed germination was much more synchronised under white light than under darkness. In the field, emergence occurred in both environments, but a greater percentage was observed under full sun. Seedling emergence occurred at the same rate and synchronisation index under both conditions. C. excavata has a high invader potential in open areas and shaded environments.

Germination bi­ology of Parthenocissus quinquefolia (L.) Planch. (Vi­taceae)

“…Positive correlation of percent of germination also was shown for Clausena excavata Burm. f. (Vieira et al 2010), Piper aduncum L. (Rocha et al 2005;Dousseau et al 2011), Crassocephalum crepioides (Benth.) S. Moore, Ageratum conyzioides L. (Yuan & Wen 2018), Rumex confertus L. (Kołodziejek & Patykowski 2015) and numerous other invasive plant species.…”

“…Invasion success of alien plant species heavily depends on its germination mechanisms, wherein broad or narrow tolerance to key ecological factors can predict a possibility to occupy a certain habitat. Seed germination studies are important for understanding the biological and ecological traits of plant species (Borghetti & Ferreira 2004;Vieira et al 2010). Ecology of germination can explain biogeographic distribution of many plant species and predict possible environments susceptible to invasion (Cordell et al 2002;Borghetti 2005;Vieira et al 2010).…”

“…Seed germination studies are important for understanding the biological and ecological traits of plant species (Borghetti & Ferreira 2004;Vieira et al 2010). Ecology of germination can explain biogeographic distribution of many plant species and predict possible environments susceptible to invasion (Cordell et al 2002;Borghetti 2005;Vieira et al 2010). This information is useful for developing effective management programs on control of alien plant species expansion.…”

Are the Alien Species of Melastomataceae and Bombacoideae a Potential Risk for Brazilian Cerrado?

“…Studies in the last two decades about seed germination patterns of Cerrado species [5] may allow some initial comparisons. Some differences in seed ecology between alien or invasive and local or native species were identified focusing on germinability, different light conditions for germination, stratification requirements, dormancy strategies, seedling growth or vigour and other traits [6] [7] [8] [9] [10].…”

Seed germination and seedling morphology of Artabotrys hexapetalus

“…internal and external factors. Vieira et al (2010) refer to temperature, light, and soil humidity as the most important environmental factors controlling seed germination and seedling establishment. However, there are many factors that inhibit or prevent germination and different plant species vary in the range of factors that prohibit germination.…”