Germination responses of Lycium humile, an extreme halophytic Solanaceae: understanding its distribution in saline mudflats of the southern Puna

REGINATO, MARIANA; CANTERO, JUAN JOSÉ; LLANES, ANALÍA; LUNA, VIRGINIA; PALCHETTI, MARÍA VIRGINIA; BARBOZA, GLORIA

ACTA BOTANICA BRASILICA

SOC BOTANICA BRASIL

Lugar: San Pablo; Año: 2020 vol. 34 p. 540 - 548

0102-3306

Although knowledge about halophytic Solanaceae is scarce, it is known that several species within genus Lyciumtolerate salinity. Lycium humile grows in highly saline soils in mudflats near saline Andean lakes. This study evaluatedthe germination responses of L. humile under different scarification methods, photoperiods, temperatures andsaline conditions and, simultaneously, tested seedling survival under different iso-osmotic conditions. Dormancyand germination were found to be regulated by interactions with different factors, with the highest germinationpercentages being obtained by immersion in sulfuric acid, with a temperature of 25 °C and a temperature regimeof 5/25 °C, under which seeds were neutrally photoblastic. As osmotic potential of saline solutions decreased,germination also decreased drastically but the seedling survival percentage was higher than 30 % at 600 mM NaCl.No seeds germinated in any of the polyethylene glycol (PEG) solutions and no seedling survival was observedfrom -1.2 MPa PEG solutions. More than 90 % of seeds incubated in NaCl were able to recover germination afterbeing transferred to distilled water, independently of NaCl treatments. We concluded that the effects of extremeenvironmental conditions on germination responses and seed tolerance to salinity may determine the occurrenceand restricted distribution of L. humile.