1Department of Seed Science and Technology, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu -641003, India
2Department of Seed Science and Technology, FC&RI, Mettupalayam, Tamil Nadu, India
*Email: lprasanna.agrico@gmail.com
Online published on 24 June, 2014.
In many crop species, seed germination and early seedling growth are the most sensitive stages to any stress. In order to evaluate the effect of different seed priming techniques on germination of paddy under different temperatures a factorial experiment was conducted with six varieties. Seeds were primed for 12h in seven priming media (salicylic acid 50 ppm, ascorbic acid 200ppm, citric acid 200ppm, proline 0.2%, calcium chloride 2%, Na2HPO4 100ppm and distilled water) at three different temperatures (30°C, 38°C and 43°C) to observe the germination and related parameters. Results indicated that an increase in heat stress decreased germination components such as germination percentage, speed of germination, root length, shoot length and vigour index. Ascorbic acid and salicylic acid pre-treatment @ 200ppm and 50ppm respectively results in improvement of germination properties of paddy under heat stress condition because of its antioxidant capacity. The other treatments also enhanced the germination properties. Priming treatments including hydropriming resulted in the increased activity of α-amylase which in turn has resulted in better mobilization of stored carbohydrate reserves resulted in improvement of germination and other related parameters.
Ascorbic acid and salicylic acid priming improves germination under high temperature.
α-amylase is the main enzyme responsible for increased speed of germination in primed seed
Paddy, temperature, stress, priming, ascorbic acid, salicylic acid
