Shoot Responses of Six Lythraceae Species to Flooding

Abstract

The large family Lythraceae has several genera and species that show tolerance to flooding; one species, Lythrum salicaria (purple loosestrife), is considered invasive in North American wetlands. It is not clear, however, which characteristic(s) contribute to the invasive nature of L. salicaria, but those that contribute to improved flood tolerance may be responsible. This study examined the response of the shoot system of several members of the Lythraceae, three Lythrum species (L. salicaria, L. hyssopifolia, L. alatum), Decodon verticillatum, Pleurophora anomala and Heimia myrticifolia, to flooding to determine if these species differ in their response in comparison to L. salicaria. All species, except L. hyssopifolia, responded to flooding by increasing total plant height. All species, except H. myrticifolia, formed a phellem of significantly wider diameter at the stem base of flooded plants compared to controls. This phellem consisted of alternating bands of small, isodiametric cells and radially elongated cells separated by large air lacunae forming a very specialized aerenchyma. The small cells had Casparian band‐like wall modifications and occasionally displayed modifications that included all cell wall surfaces. The development of extensive aerenchymatous phellem in flooded plants may increase the air space continuum from shoot to root in shoots that have undergone secondary growth. Given that these species displayed similar responses to flooding, the purported invasiveness of L. salicaria cannot be attributed to presence of any of the characteristics studied.

Role of Abscisic Acid in Flood-Induced Secondary Aerenchyma Formation in Soybean (Glycine max) Hypocotyls

“…and Lythrum spp. (Stevens et al, 1997(Stevens et al, , 2002Lempe et al, 2001;Stockey, 2003, 2006). This form of aerenchyma is a white spongy tissue that consists of living cells with non-suberized walls and is referred to as "secondary aerenchyma" (Arber, 1920;Fraser, 1931;Williams and Barber, 1961;Jackson and Armstrong, 1999).…”

Secondary Aerenchyma Formation and its Relation to Nitrogen Fixation in Root Nodules of Soybean Plants (Glycine max) Grown under Flooded Conditions

“…chymatous cells with abundant intercellular spaces filled Leguminous plants have a symbiotic relationship with with air between their cells (Scott and Wager, 1888; root nodule bacteria, and, therefore, oxygen is required Batten, 1918;Lempe et al, 2001;Stevens et al, 1997; for respiration of both roots and nodules. When there is Walker et al, 1983;Angeles, 1992;Arber, 1920; Metan oxygen deficiency in flooded soils, the nitrogenase calfe, 1931; Sifton, 1945).…”

Caracterização morfoanatômica e histoquímica de Cuphea carthagenensis (Jacq.) J.f. Macbr. (Lythraceae)

“…O aerênquima formado no felema é ainda pouco conhecido e investigado, apesar de ter sido descrito já em 1889 por Schenk 5 (apud Lempe et al 2001). De acordo com Stevens et al (2002), isso talvez se deva ao fato de que a maioria das plantas investigadas, portadoras de aerênquima, não possui capacidade de crescimento secundário ou ainda, porque podem ter sido analisadas em estágio jovem.…”

“…Em caules, o felema não se apresentou aerenquimatoso, provavelmente, em função destes não terem sido expostos a alagamento na área amostral. Conforme as investigações de Lempe et al (2001) Fig. 13, escala = 50 μm.…”

“…aerênquima secundário de C. carthagenensis é semelhante àquela descrita para o felema do caule de Pleurophora anomala e Heimia myrticifolia (Lempe et al 2001). A presença de suberina nas células achatadas e justapostas do felema aerenquimatoso de C. carthagenensis pode evidenciar uma função semelhante à da endoderme.…”