Abiotic stresses increase plant regeneration ability

Abstract

In disturbed habitats, vegetative regeneration is partly ruled by plant reserves and intrinsic growth rates. Under nutrient-limiting conditions, perennial plants tend to exhibit an increased allocation to storage organs. Under mechanically stressful conditions, plants also tend to increase allocation to below-ground biomass and storage organs. We tested whether those stresses acting differently on plants (nutrient level versus mechanical forces) led to similar effect on storage organs and regeneration ability. We measured, for an aquatic plant species, (1) the size and allocation to storage organs (stems) and (2) the regeneration ability of the storage organs. Plant stems were collected in 4 habitats ranked along a nutrient stress gradient, and having encountered null versus significant mechanical stress (flowing water). All stems were placed in similar neutral conditions and left for a period of 6 weeks before measuring their survival and growth. Dry mass allocation to the storage organ (stem) was higher in stressful habitats. Moreover, stress encountered by plants before the experiment significantly affected regeneration: stems of previously stressed plants (i.e. plants that had grown in nutrient-poor or mechanically stressful habitats) survived better than unstressed ones. Stems of plants having encountered mechanical stress before the experiment had increased growth in nutrient-rich habitats but reduced growth in the poorest habitats. These results demonstrate that regeneration could rely on the level of stress previously encountered by plants. Stress could lead to greater regeneration ability following mechanical failure. The possible mechanisms involved in these results are discussed.

Turion production and nutrient reserves in Potamogeton crispus are influenced by sediment nutrient level

“…These results may be explained by the finding that nutrient limitation causes resources to be re-allocated to carbohydrate reserves instead of being utilized for vegetative growth processes (Hangelbroek et al 2003). For instance, plants in stressful habitats allocate more dry mass to the development of storage organs than plants in favorable habitats (Puijalon et al 2008). The plasticity of P. crispus was demonstrated by its ability to re-allocate resources to carbohydrate reserves (turions in this case) when faced with nutrient-poor conditions.…”

Moderate abiotic stresses increase rhizome growth and outgrowth of axillary buds in Alstroemeria cultured in vitro

“…Thus, they develop dormancy and form storage organs to survive an unfavorable season and to ascertain fast regrowth after that. Many plants that grow in stressful habitats have increased mass allocation to the storage organs (Chapin III et al 1990;Ryser and Urbas 2000;Hutchings and John 2004;Puijalon et al 2005;Puijalon et al 2008). Alstroemeria responds to moderate heat stress similarly by increasing rhizome growth.…”

The Effects of Carbon Dioxide Fertilization on the Ecology of Tropical Seagrass Communities

“…On the basis of our observations, we hypothesize that a similar mechanism may operate for T. testudinum. Prior work with the freshwater macrophyte, Berula erecta has experimentally demonstrated increased carbohydrate storage with nutrient limitation, and decreased carbohydrate storage under nutrient replete conditions (Puijalon et al 2008).…”