Phenotypic Plasticity Early in Life Constrains Developmental Responses Later

Abstract

Abstract. Plastic stem-elongation responses to the ratio of red:far-red (R:FR) wavelengths enable plants to match their phenotype to local competitive conditions. However, elongation responses early in the life history may occur at the cost of reduced plasticity later in the life history, because elongation influences both allocation patterns and structural integrity. A common-garden experiment was performed to test whether seedling responses to R:FR affect biomass allocation, biomass accumulation, and subsequent plasticity to the cue. Seedlings of Abutilon theophrasti were stimulated to elongate by low R:FR treatments, and subsequent growth and plasticity was compared with nonelongated individuals. Elongated seedlings were less responsive than nonelongated ones to a second bout of low R:FR. Thus, seedling plasticity to R:FR reduces subsequent responsiveness to this cue. This negative association across life-history stages suggests an important constraint on the evolution of plastic stem responses, because selection in A. theophrasti has previously been shown to favor increases in early elongation in combination with increased later elongation. The reduced responsiveness of elongated seedlings to R:FR appeared to result from a structural feedback mechanism, indicating that the opportunity cost of early responses may be lower in environments providing structural support. Adaptive plasticity is commonly viewed as an evolutionary strategy that enables organisms to match their phenotype to local conditions and avoid opportunity costs (Levins

Early rhizosphere microbiome composition is related to the growth and Zn uptake of willows introduced to a former landfill

“…One role of EM symbionts is to provide plants with nutrients such as phosphorus, and plant‐associated EM fungi have been shown to differentially affect weathering of rock phosphorus (Wallander, ). The specific benefits provided by EM fungi at the site used in this study are unknown, but regardless, changes in early phenological trajectories caused by differences in plant health or nutrient availability may limit future optimization of certain plant growth traits (Gedroc et al ., ; Weinig and Delph, ). Although heterogeneity in soil parameters throughout the site may lead to differences in maximal potential plant growth, studies controlling the composition of initial fungal colonists will help to distinguish the roles of microbiome selection and abiotic factors in the ultimate success of introduced plants during site restoration.…”

Shade avoidance: an integral component of crop–weed competition

“…It is possible that triggering the shade avoidance response early in development may constrain subsequent responses to low R/FR signals from intra‐specific competition. Research by Weinig and Delph (2001) on velvetleaf ( Abutilon theophrasti Medic.) suggests that once shade avoidance is expressed, the ability of the plant to utilise this same response at a later stage of development may be reduced.…”

Phenotypic integration may constrain phenotypic plasticity in plants

“…Limits to plasticity can cause plants to fail in producing the optimal phenotype for a given environment (Pigliucci 2005). This can occur when environmental cues are unreliable (Tufto 2000), when there is a long time‐lag between the detection of the environmental cue and the actual phenotypic response (Stomp et al 2008), when complex environments affect the plant response to the main environmental cue (Weinig 2000), or when elicitation of plasticity in young seedlings limits the extent of plastic responses to the same environment later in plant life (Weinig and Delph 2001). This study provides evidence for another limit to phenotypic plasticity of plants by showing that the phenotypic trait architecture may constrain their plastic responses to the environment.…”