Malondialdehyde content as a potential biochemical indicator of tolerant Cenchrus ciliaris L. genotypes under heat stress treatment

TOMASSINO, E.; GRIFFA, S.; GRUNBERG, K; RIBOTTA, A.; LÓPEZ COLOMBA, E.; CARLONI, E.; QUIROGA, M.; LUNA, C.

GRASS AND FORAGE SCIENCE (PRINT)

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2012 vol. 67 p. 456 - 459

0142-5242

Buffel grass (Cenchrus ciliaris L.) is an important foragegrass in arid and semiarid regions. As part of a geneticimprovement programme, four genotypes [Biloela (Bl),Americana (Am), Texas (Tx) and Sexual (Sx)] werecategorized by tolerance to heat stress in a greenhouseexperiment. At 30 d after sowing, half of the plants(control plants) were transferred to growth chambers(28C day per night), and the other half (pre-treatedplants, Prt) were exposed to heat stress treatment (0, 24,48 and 72 h; 45C day per night). Malondialdehyde(MDA) content, an indicator of oxidative damage, wasdetermined from foliar samples. During heat stress, Sxshowed the earliest increase in MDA (at 24 h) followedby Tx (48 h) and Am and Bl (72 h). Results werecompared with heat-stress tolerance evaluated asmorphological traits at the end of recuperation (60 dafter sowing). Fresh weight and aerial plant height werelowest in the Prt-Sx genotype and highest in Am and Blgenotypes; Tx showed intermediate tolerance. Resultssuggest that tolerance to heat stress in C. ciliaris genotypescould be related to the capacity for regulating theoxidative damage increase. Foliar MDA content mighttherefore be used in a genetic improvement programmeof C. ciliaris as a potential biochemical indicator for arapid, simple and low-cost identification of heat-stresstolerant genotypes.