Effects of cell number and cell size on petiole length variation in a stoloniferous herb

Abstract

In stoloniferous species, the length of petioles is of pivotal importance because it determines the position of leaf blades within the canopy. From a mechanistic perspective, two developmental processes, cell division and cell elongation, are responsible for the length of a given petiole. This study aimed at quantifying the relative contributions of cell division and cell elongation to genotypic and plastic variation in petiole length of the stoloniferous herb Trifolium repens. Thirty-four genotypes of T. repens were grown under high light conditions and simulated canopy shade. Cells were counted and their lengths measured on epidermal prints from fully grown petioles of leaves that had been initiated in the experimental light conditions. Cell number was the main trait explaining petiole length differences among genotypes grown under high light, while both cell number and length changed in response to shading. Our study revealed a strong negative correlation between shade-induced changes in cell number and cell length: genotypes that responded to shading by increasing cell numbers hardly changed in cell length, and vice versa. Our results suggest that genotypic and phenotypic variation in petiole length results from a complex interplay between the developmental processes of cell elongation and cell division.

Assessment of the Diversity of Leaf Epidermal Traits of Dipcadi Filamentosum Medik Among Different Co-Geographical Regions in Nigeria

“…Rather larger changes in cell water relations are predicted for small changes in cell size. This prediction supports the hypothesis that plants or tissues with the smaller cell size will be more tolerant of low water potential (Ainsworth et al, 2006;Muller et al, 2007;Rymen et al, 2007;Tompson 2008;Weijschede et al, 2008).…”

Large Root Cortical Cell Size Improves Drought Tolerance in Maize

“…Treatment is the moisture regimes imposed, genotype is the phenotype class (large CCS and small CCS), and RWC is the leaf RWC (%). deflection than large cells (Weijschedé et al, 2008). This is particularly important for root penetration in hard soil, which is common under drought.…”

Transgenerational effects of land use on offspring performance and growth in Trifolium repens

“…Wang and M. van Kleunen, personal observation). Previous studies of T. repens reported similar petiole-elongation responses to shading (Huber et al 1998;Weijschedé et al 2006Weijschedé et al , 2008a. Such shade-avoidance responses are also frequently reported for other species when they experienced intraspecific (Vermeulen and During 2010) or interspecific competition (Barthram 1997;van Kleunen and Fischer 2001;Weijschedé et al 2008b).…”