Putrescine improve low temperature tolerance of fennel (Foeniculum vulgare Mill.) seeds

Abstract

The effects of polyamine priming on the germination behaviour of fennel at low temperatures were investigated. For preparing the putrescine pretreatments, seeds were divided into four parts. Two samples primed into putrescine (10 or 20 ppm) for 24 h, other samples were as controls. In order to eliminate the effect of water from test results, seeds were soaked in water only. After the priming, seeds were dried and used for germination test at 10 and 20 ºC. Except for seedling dry weight, all of the priming treatments improved germination performance and seedling growth of fennel seeds. Maximum germination percentage was achieved by 10 ppm Put application and lower value was observed in control seeds. About the energy of germination and mean germination time, polyamine treatments had better effect than hydropriming, but similar results was observed from seeds treated by 10 ppm Put and hydroprime on root and shoot length. Results showed that adequate presence of Put in the priming media had better than priming with water only. However, high concentrations of Put had not significant effect as well as 10 ppm Put. These results indicated that 10 ppm Put priming could be as an effective method to improve low temperature tolerance of fennel seeds.