A quantitative revision of the waterlogging tolerance of perennial forage grasses

DI BELLA CE; GRIMOLDI AA; STRIKER GG

Crop and Pasture Science

Elseiver

Año: 2022 vol. 73 p. 1200 - 1212

1836-0947

Waterlogging tolerance of eight C4 and seven C3 perennial forage grasses was reviewed. Themedian waterlogging duration was similar between species’ type, ranging between 18 and 21days. Inter- and intra-species variability was found in shoot and root biomass in response towaterlogging. Urochloa brizantha (C4), Brachiaria hybrid (C4) and Dactylis glomerata (C3)were the less tolerant species to waterlogging (shoot biomass median of 45%, 53% and 80%of controls), while U. humidicola (C4), Paspalum dilatatum (C4), Festuca arundinacea (C3)and Lolium perenne (C3) were the most tolerant (shoot biomass median of 97%, 101%, 87%and 94% of controls). A similar ranking of responses was found among species for rootbiomass. The formation of aerenchyma/root porosity (key trait for waterlogging tolerance)was evaluated mainly on U. humidicola and P. dilatatum (C4 waterlogging tolerant species),which showed considerable constitutive porosity (13% and 32%) and final values of 30%and 41% under waterlogging. Net photosynthesis and stomatal conductance as typical leafphysiological responses matched species’ waterlogging tolerance, being the impact ofhypoxia higher in C3 than in C4 species. Gaps in knowledge about waterlogging tolerance inforage grasses are: (i) additional studies on C3 perennial grasses for temperate pasture areasprone to waterlogging, (ii) identification of traits and responses aiding to plant recovery afterwaterlogging, (iii) reassessment of waterlogging tolerance considering plant developmentalstage (e.g. seedlings vs adult plants), and (iv) evaluation of sequential (i.e. waterlogging –drought) and combined (i.e. waterlogging + salinity) stresses, which often co-occur in pasturelands.