Different strategies of Lotus japonicus, L. corniculatus and L. tenuis to deal with complete submergence at seedling stage

Abstract

Two main strategies allow plants to deal with submergence: (i) escape from below water by means of shoot elongation, or (ii) remaining quiescent under the water until water subsides and then resume growth. We investigated these strategies in seedlings of Lotus japonicus, L. corniculatus and L. tenuis subjected to control and submergence for 12 days, with a subsequent 30-day recovery period. All three species survived submergence but used different strategies. Submerged seedlings of L. japonicus exhibited an escape strategy (emerging from water) as a result of preferential carbon allocation towards shoot mass and lengthening, in detriment to root growth. In contrast, seedlings of L. corniculatus and L. tenuis became quiescent, with no biomass accumulation, no new unfolding of leaves and no shoot elongation. Upon de-submergence, seedlings of L. japonicus had the lowest recovery growth (a biomass and shoot height 58% and 40% less than controls, respectively), L. corniculatus was intermediate and L. tenuis showed the greatest recovery growth. Previously submerged seedlings of L. tenuis did not differ from their controls, either in final shoot biomass or shoot height. Thus, for the studied species, quiescence appears to be an adequate strategy for tolerance of short-term (i.e., 12 days) complete submergence, being consistent with field observations of L. tenuis colonisation of flood-prone environments.

Phenomic networks reveal largely independent root and shoot adjustment in waterlogged plants of Lotus japonicus

“…; Striker et al . ). The number of shoots can also be modified by waterlogging, depending on the balance between mortality and appearance of shoots (Malik et al .…”

“…L. japonicus shows tolerance to waterlogging and is able to survive at least 12 d of submergence at seedling stage (Striker et al . ) and 30 d of waterlogging in adult plants (Rocha et al . ).…”

Growth, morphology and gas exchange responses of two-year-oldQuercus castaneifoliaseedlings to flooding stress

“…Consequently, after flooding, root growth possibly will be prioritized over shoot growth to re-establish the shoot-toroot ratio typical of plants growing under drained soil; this seems to be indicated by the intermediate value for this ratio observed in Q. castaneifolia seedlings (see also shoot-to-root ratio re-establishment for Lotus spp. during recovery in Striker et al 2012).…”

“…lowland and wetlands). The scarcity of oxygen resulting after the soil is flooded triggers, in tolerant woody species, a suite of morpho-physiological adaptations related to their survival and growth under anaerobic conditions (Kozlowski 2002;Striker et al 2005Striker et al , 2008Striker et al , 2012Sairam et al 2008;Colmer & Voesenek 2009;Parad et al 2013). Soon after flooding occurs, oxygen exhaustion in the rhizosphere leads to a reduction in water and nutrient uptake by the hypoxic roots (Else et al 2001).…”

Relationships between phenotypic variation in osmotic adjustment, water-use efficiency, and drought tolerance of seven cultivars of Lotus corniculatus L.

“…In drought-prone environments, some species of the Lotus genus have been suggested to be a promising genetic resource, given their high forage yield potential and high capacity to adapt to marginal environments (Striker et al, 2005;Teakle et al, 2006;Real et al, 2008;Garcia et al, 2008;Manzur et al, 2009;Teakle et al, 2010;Striker et al, 2012). Lotus corniculatus is a perennial forage legume that originates in the Mediterranean Basin and North Africa (Kirkbride, 1999) and has been widely used in southern Europe, North and South America, and New Zealand.…”