Plant biology and physiology, Biologie et physiologie végétales, Ecology, Ecologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Plantes parasites. Mauvaises herbes, Parasitic plants. Weeds, Malherbologie, Weeds, Angiospermae, Dicotyledones, Spermatophyta, Asymétrie, Asymmetry, Asimetría, Croissance, Growth, Crecimiento, Espèce envahissante, Invasive species, Especie invasora, Germination, Germinación, Invasion, Invasión, Inégalité, Inequality, Desigualdad, Mauvaise herbe, Weed, Malezas, Plante, Plant, Planta, Potentiel semencier, Seed bank, Banco de semillas, Taux croissance, Growth rate, Tasa crecimiento, Verbenaceae, Ecologie végétale, Plant ecology, Ecología vegetal, Lantana camara, Australia, Biological-invasions, Gini coefficient, Growth rates, Seed germination, Seed-bank, Size inequality, and Weeds
Lantana camara L. (Verbenaceae) is a weed of great significance in Australia and worldwide, but little is known about connections among components of its life history. We document over a 3-year period, the links between L. camara seed-bank dynamics and its above-ground growth, including size asymmetry in four land-use types (a farm, a hoop pine plantation and two open eucalypt forests) invaded by the weed near Brisbane, Queensland Australia. Seed-bank populations varied appreciably across sites and in response to rainfall and control measures, and they were higher (∼ 1,000 seeds/m2) when annual rainfall was 15―30 % below the long-term yearly average. Fire reduced seed-bank populations but not the proportion germinating (6―8 %). Nearly a quarter of fresh seeds remain germinable after 3 years of soil burial. For small seedlings (<10 cm high), the expected trade-offs in two life-history traits—survival and growth—did not apply; rather the observed positive association between these two traits, coupled with a persistent seed-bank population could contribute to the invasiveness of the plant. Relationships between absolute growth rate and initial plant size (crown volume) were positively linear, suggesting that most populations are still at varying stages of the exponential phase of the sigmoid growth; this trend also suggests that at most sites and despite increasing stand density and limiting environmental resources of light and soil moisture, lantana growth is inversely size asymmetric. From the observed changes in measures of plant size inequality, asymmetric competition appeared limited in all the infestations surveyed.