S-methylmethionine alleviates the cold stress by protection of the photosynthetic apparatus and stimulation of the phenylpropanoid pathway.

Páldi, K.; Rácz, I.; Szigeti, Z.; Rudnóy, S.

Maize ( Zea mays L.) seedlings were pretreated with 0.001 g dm S-methylmethionine (SMM) in the nutrient solution for 24 h and then subjected to chilling (6 °C for 2, 4, 6, 10, and 24 h). Cold stress significantly decreased the maximum quantum yield of photosystem II (variable to maximum chlorophyll fluorescence ratio, F/F) during the whole experiment but SMM pretreatment significantly reduced this decline. Content of phenolics and anthocyanins increased in response to low temperature, and SMM pretreatment further intensified the synthesis of these protective agents. These findings were supported by increased expression of genes coding enzymes of the phenylpropanoid pathway leading to synthesis of cinnamate-4-hydroxylase (C4H) and chalcone-synthase (CHS). Our results indicate that SMM pretreatment alleviates the low temperature stress by reducing the damage of the photosynthetic apparatus and stimulating the phenylpropanoid pathway.

PHYSIOLOGICAL effects of cold temperatures; VITAMIN U; PHOTOSYNTHESIS; PHENYLPROPANOIDS; SEEDLINGS; PLANT nutrients; FLUORESCENCE

Biologia Plantarum, 2014, Vol 58, Issue 1, p189

0006-3134

Academic Journal

10.1007/s10535-013-0356-7