Foliar anatomical changes in soybean plants under water stress.

PARDO, M.E.; LUQUE, A.C.; DEBES, M.A.; VELICCE, G.; CASTAGNARO, A.P.; ARIAS, M.E.

San Miguel de Tucumán

Jornada; XXXI Jornadas Científicas de la Asociación de Biología de Tucumán.; 2014

Asociación de Biología de Tucumán.

The foliar characteristic could be decisive for plants survival under water deficit conditions. Through evolution, plants have responded to water stress by developing physiological, morphological and anatomical adaptations. The aim of this study was to identify anatomical changes in leaf of Glycine max varieties subjected to hydric shortage. We worked with control and stressed plants after 21days. Leaves fixed in FAA (formalin, Acetic acid, ethyl alcohol) of 5 individuals per treatment (control and stressed) of A8000 (tolerant), Munasqa (tolerant) and TJ2049 (sensitive) were analyzed. Transparence and transverse cuts of leaflets and petioles were made. For staining different dyes were used. The observations were made with an optical microscope Leica DM500. Trichome density on both epidermis increased in Munasqa and A8000 stressed varieties, while TJ2049 remained similar to the control values. Stomatal density decreased in TJ2049; increased in Munasqa and unchanged in A8000. The leaflets? thickness decreased markedly in A8000 and mild in Munasqa variety, but in TJ2049 thickness increased. Changes in petioles at vascular bundles were observed. In Munasqa and A8000 varieties, beams size decreased and lignification increased, while in TJ2049 variety lignification was lower. The diameter of xylem vessels decreased in all varieties; however, the number of vessels was lower in A8000 and Munasqa. The results coincide with tolerance/sensitivity description for each variety. The most sensitive characters to stress conditions, indirectly evaluated using test coloring, were: pubescence, stomatal density and lignification vessels.