Disentangling the Effects of Genotype and Environment on Growth and Wood Features of Balfourodendron riedelianum Trees by Common Garden Experiments in Brazil

Abstract

Intraspecific studies with populations replicated in different sites allow the effects of genotype and environment on wood features and plant growth to be distinguished. Based on climate change predictions, this distinction is important for establishing future patterns in the distribution of tree species. We quantified the effects of genotype and environment on wood features and growth of 30-year-old Balfourodendron riedelianum trees. We used three provenances planted in two common garden experiments with difference in precipitation and temperature. We applied linear models to estimate the variability in wood and growth features and transfer functions to evaluate the responses of these features to temperature, precipitation, and the standardized precipitation evapotranspiration index (SPEI). Our results showed that genotype had an effect on vessels and rays, where narrower vessels with thinner walls and larger intervessel pits, and shorter, narrower and more numerous rays were observed in provenances from drier sites. We also observed the effect of the environment on wood features and growth. Trees growing in the wetter site were taller and larger, and they had wider vessels with thicker walls and lower ray density. Transfer functions indicated that an increase in temperature results in larger vessels with thicker walls, taller and denser rays, shorter and narrower fibers with thinner walls, and lower wood density. From a functional perspective, these features make trees growing in warmer environments more prone to drought-induced embolisms and more vulnerable to mechanical damage and pathogen attacks. Tree growth varied with precipitation and SPEI, being negatively affected in the drier site. Overall, we demonstrated that both genotype and environment affect wood features, while tree growth is mainly influenced by the environment. Plastic responses in hydraulic characteristics could represent important functional traits to mitigate the consequences of ongoing climate change on the growth and survival of the species within its natural range.

Soil Effects on Stem Growth and Wood Anatomy of Tamboril Are Mediated by Tree Age

“…A functional advantage of thicker-wall fibers in the wood of taller trees of "tamboril" grown in eutrophic soil is to reinforce weakness areas, such as those close to the vessels [41]. Our findings demonstrated that fiber wall thickness was positively correlated to vessel diameter, suggesting that the thickening of the fiber walls would form in secondary xylem a matrix of fibers protecting the vessels of possible drought-induced negative pressure [42].…”

Assessing inter‐intraspecific variability of leaf vulnerability to embolism for 10 alpine Rhododendron species growing in Southwestern China

“…Toluidine blue staining was applied to the slides of the cross‐sections for 30 minutes, followed by photography. ImageJ software was utilized to process and analyze the images, quantifying anatomical traits (Figure S2) such as vessel density (VD) (Cai et al, 2013), vessel diameter (DV) (Silva et al, 2020), conduit wall span (b) (Hacke et al, 2001), and vessel wall thickness (t) (Hacke et al, 2001). Moreover, using ImageJ software, additional morphological traits, including leaf thickness, upper and lower epidermal thickness, palisade tissue thickness, and spongy tissue thickness were measured.…”