The Materials And Methods Of Seed Vigour Testing

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Materials and methods Seeds Eighteen seed lots from six varieties that produced in three consecutive years (2012 to 2014) gathered from different climates of Iran (Table 1). All of those stored in very different condition from unprotected place to the cooled storehouse. Preliminary Seed Vigour Testing The standard germination protocol for the between paper method (ISTA 2008) was used to evaluate four replicates of 100 seeds from each seed lot at four temperatures: 20°C, 17°C, 15°C and 13°C in the dark. Mean radicle emergence time (MRET), mean germination time (MGT) and standard germination (SG) were calculated and compared with field emergence (FE) and mean emergence time (MET) measured in the field. In order to evaluate MRET and FE, the …show more content…

The containers of towels were put a transparent box and placed in a tied plastic bag and held in an incubator at all temperatures ± 0.5°C. The placement of the boxes was rotated in the incubator after each measuring. Counts of germination for six chosen six seed lots were done every 6 h for 4 days at 20°C and every 6h for 4 days at 20°C. Counts were done for just germination (JG or RE), that is, when the radicle first appeared through the pericarp and physiological germination (G) when a 2mm radicle had been seen. Two measures of the relative rates of germination were calculated: 1. Mean just germination time (MJGT) = Σ (nt) / Σ n, where n = number of seed newly germinated (just germinated criterion) at time t; t = days from seeding to germination. 2. Mean germination time (MGT) was calculated using the same formula, but using the physiological assessment of germination (2mm radicle). The MJGT and MGT were assessed for each replicate and used to create a mean for each seed lot. Only seeds that finally produced normal seedlings (ISTA, 2005) were included. All that tests were performed at 20°C to 17°C, 15°C and 13°C temperatures in order and in the same way sequence, fully implemented. Imbibition After identifying relationships between MJGT, MGT and Germination at different times and temperatures, 15°C were chosen for imbibition testing because it was the best match with field tests' results. Water uptake and

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