Morphological Plasticity and Gas Exchange of Ligustrum lucidumW.T. Aiton in Distinct Light Conditions

Abstract

The objective of this study was to understand the different morpho-physiological strategies of Ligustrum lucidum, an invasive species occurring in Brazilian forest fragments under heterogeneous light conditions. Ten individuals of L. lucidum were selected and evaluated for morphological of the leaves and physiological traits. For morphological parameters were evaluated: length, width, area, angle, petiole length, dried mass, total thickness, palisade parenchyma and spongy parenchyma thickness, abaxial and adaxial epidermis thickness, stomata density, leaf density and specific leaf area. The physiological traits were vapor-pressure deficit, assimilation rate, CO 2 substomata concentration, intrinsic water-use efficiency, transpiration rate and stomatal conductance. All the physiological variables and most morphological variables presented significant differences between light conditions. Phenotypic plasticity indexes were not high as expected. However, phenotypic integration among the morphological and physiological attributes appeared to explain better these results, as observed on the relationship among assimilation rates, palisade parenchyma thickness and SLA. Phenotypic integration could increase the species adaptive responses efficiency, making it more competitive to occupy and to establish in new niches.

Effect of environmental gradients on leaf morphological traits in the Fandoghlo forest region (NW Iran)

“…All morphological traits except SLA were higher at the forest edge than in the forest understory. At higher light environments, SLA tended to decrease (Li et al 2014, Larcher et al 2015, as observed in the present study. LMA increases with decreasing forest cover, likely due to the increased light availability and water stress (Neyret et al 2016).…”

Organization of leaf vascular system and gas exchange in seedlings of Guazuma ulmifolia Lam. in different light conditions

“…Considering light as one of the most limiting factors for photosynthesis (Chazdon & Fetcher, 1984), seedlings submitted to full sunlight showed greater photosynthesis (Table 1). Larcher et al (2015), obtained similar results in Ligustrum lucidum, where it demonstrated lower values of photosynthesis in the shade.…”

“…The different luminous environments influenced the physiological and anatomical parameters. Several authors have observed the effect of luminosity on these parameters in tree species (Larcher et al, 2015;Felsemburgh et al, 2016;Dardengo et al, 2017), and Guazuma ulmifolia is considered a pioneer species tolerant to greater light (Lorenzi, 1992). We observed that G. ulmifolia showed characteristics such as increased photosynthetic rate, stomatal conductance and anatomical features such as thickness of parenchyma tissues, which refer to pioneer species tolerant to high light (Aragão et al, 2014;Dardengo et al, 2017).…”

Plasticidade morfoanatômica foliar em Smilax campestris (Smilacaceae) em gradiente ambiental de restinga, SC, Brasil

“…O incremento da espessura do mesofilo através do investimento em parênquima lacunoso tem sido discutido como uma estratégia de otimizar processos fotossintéticos, visto que o espaço intercelular ocorrente no parênquima lacunoso favorece o transporte de gases no mesofilo (Tian et al 2016) e complementa a eficiência de absorção luminosa. A combinação de parênquimas paliçádico e lacunoso espessos, observada nas populações de S. campestris, aumenta a assimilação e, por consequente, o crescimento das plantas (Larcher et al 2015). Em adição, a maior produção de tecido fotossintético em indivíduos da restinga herbácea, se comparados às demais formações de restinga, pode ser resultante da melhor absorção de K, Mg e P, proporcionado pelo maior teor de Ca neste local, efeito denominado como "efeito Viets" (Viets 1944).…”