The effect of seed coat colour on mustard (Brassica compestrisVar. Parkland) seed germination under salinity and drought stress

In order to assess the germination characteristics of mustard heteromorphic seeds (black and yellow) under salinity and drought stress, two separate experiments carried out as factorial based on completely randomized design with four replications and seven treatments in Agriculture Faculty of Ferdowsi University of Mashhad. The studied factors included salinity and drought treatments in seven levels (zero, -2, -4, -6, -8, -10 and -12 bar) and seed coat color in two levels (black and yellow). The results showed the significant and negative effect of salinity and drought stress on germination characteristics in both seed (black and yellow). In both seed (black and yellow), all measured germination indices reduced by increasing salinity and drought stress, but this reduction was different. Germination percentage of yellow seeds had more resistance to stress than black seeds. Germination rate, radical and plumule length and seed vigor index of black seeds was more resistance than yellow seeds. Generally findings of this research showed black seeds had more resistance to both of salinity and drought stress.