Ontogenetic Changes in Carbohydrate Storage and Sprouting Ability in Pioneer Tree Species in Peninsular Malaysia

Abstract

Sprouting ability is highly variable among different tree species. In many cases, there are trade-offs in carbon allocations between growth and storage in seedlings. However, this trade-off is likely to change with growth stages from seedling to mature plant because carbon investments in reproductive activities and/or risk of disturbance also change by species and growth stage. To examine how sprouting ability and carbohydrate storage change with growth stage, we compared two tropical secondary-forest trees, Macaranga bancana and M. gigantea, which have different ecological traits. Maximum tree size and growth rate are higher in M. gigantea. We monitored sprout growth and stored resources, including total nonstructural carbohydrate (TNC) and nitrogen in the root, among different tree sizes for 12 months following stem-cutting treatment. Sprouting ability (total sprout mass) and TNC concentrations were significantly higher in small individuals than in larger specimens in both species. TNC concentration decreased in all size classes after stem cutting. Macaranga bancana had greater sprout survivorship than M. gigantea, which had higher sprouting ability in larger tree-size classes. Thus, sprouting ability likely depends on root TNC concentration and tree-size class in both Macaranga species. Higher TNC concentration and sprout survival rates in M. bancana may be related to greater carbon allocation in survival than in growth. This hypothesis is consistent with the ecological traits of M. bancana, such as its growth rate, which was lower than that of M. gigantea.

Regeneration of Juvenile Woody Plants after Fire in a Seasonally Dry Tropical Forest of Southern India

“…) and in small‐sized individuals of tree species at a tropical secondary forest site in Malaysia (Kenzo et al . ).…”

“…One example of such properties is high root:shoot ratios (Bond & Midgley 2001) as observed in smaller-sized individuals of tree species in Australian eucalypt savannas (Werner & Murphy 2001) and Brazilian Cerrados (Hoffmann et al 2004). Another property is high total non-structural carbohydrate (TNC) concentrations in roots, as observed in tree juveniles in the Brazilian Cerrado (Hoffmann et al 2004) and in small-sized individuals of tree species at a tropical secondary forest site in Malaysia (Kenzo et al 2013).…”

Different responses of stem and soil CO2 efflux to pruning in a Chinese fir (Cunninghamia lanceolata) plantation

“…This discrepancy may be partly attributed to species differences. Sprouting species, such as Chinese fir, exhibits higher allocation to root carbohydrate storage (Schwilk and Ackerly 2005;Kenzo et al 2013), as indicated by a high amount of carbohydrate reserves in the root. After pruning, depletion in carbohydrate storage initially occurred in the stem, and depletion in carbohydrate storage was more obvious in the stem than in the root (Chesney and Vasquez 2007).…”

Roles of leaf trichomes in heat transfers and gas‐exchange characteristics across environmental gradients

“…Leaf trichomes are known to influence various biophysical processes depending on their habitat conditions (Bickford, 2016;Johnson, 1975) such as increasing water-use efficiency (WUE) through increasing vapordiffusion resistance (e.g., Kenzo, Yoneda, Azani, & Majid, 2008); maintaining leaf temperature above air temperature by decreasing sensible-heat flux (e.g., Meinzer & Goldstein, 1985) or below air temperature by reflecting radiations (e.g., Ehleringer & Mooney, 1978); avoiding photoinhibition by increasing light reflectance (e.g., Skelton, Midgley, Nyaga, Johnson, & Cramer, 2012); promoting condensation on leaf surface either to decrease water loss (e.g., Konrad, Burkhardt, Ebner, & Roth-Nebelsick, 2015) or to capture water from dew on leaf surface (e.g., Ohrui, et al 2007). Leaf trichomes are often associated with drought tolerance because plants with densely pubescent leaves are often abundant in dry environmental conditions (Aronne & De Micco, 2001;Ehleringer & Mooney, 1978;Ichie, Inoue, Takahashi, Kamiya, & Kenzo, 2016;Johnson, 1975;Moles et al, 2020;Smith & Nobel, 1977) and because pubescent individuals have lower mortality than glabrous individuals after climatic drought events even within a species (Ando, Isagi, & Kitayama, 2020).…”

“…Since in many species the density of leaf trichomes is higher on leaf lower surface, where stomata exist, than on the upper surface (e.g., Aronne & De Micco 2001;Roth, 1984), it has been believed for many years that this "direct" effect (possible higher WUE through a direct suppression of gas-exchange rates) is a major ecological advantage of leaf trichomes in dry conditions [reviewed in Bickford (2016), Johnson (1975), and Sayre (1920)]. While some previous studies supported this argument (Kenzo et al, 2008;Ripley, Pammenter, & Smith, 1999;Wuenscher, 1970), many other studies repeatedly demonstrated that the direct effect of leaf-trichome resistance on H 2 O diffusion is negligible because the leaf-trichome resistance is an order of magnitude smaller than stomatal resistance (Amada, Ichie, Onoda, & Kitayama, 2017;Benz & Martin, 2006;Ehleringer & Mooney, 1978;Johnson, 1975;Nobel, 2009;Sayre, 1920;Skelton, Midgley, Nyaga, Johnson, & Cramer, 2012).…”