تاثير محتواي رطوبت بذر بر شاخص هاي جوانه زني بذر و رشد اوليه گياهچه در چهار رقم كلزا

Effects of harvesting time on germination indices and early growth of seedling in four canola cultivars {Brassica napus L.)

In order to evaluate the effects of harvesting time on germination indices and early growth of seedling, seeds of four canola cultivars (Hyola308, Hyola401, Hyola420 and RGS003) were sown at Rice Research institute of Iran, Rasht in a split plot design in randomized complete block basis with 3 replications in 2005-2006 growing season. The seeds of four canola cultivars at four harvesting times (based on seed moisture content in one third of bottom siliques of inflorescence on main stem: 45%, 35%, 25%, 15% were obtained at grain maturity stage. The seeds were surface sterilized and tested for standard germination analysis. The experimental design was a factorial in a Completely Randomized basis with 3 replications. Germinated seeds were counted at fifth and seventh days and germination percentage, seedling length, seedling fresh weight, seedling dry weight, vigor index, germination index (GI), germination rate (GR), energy of germination (GE) and mean germination time (MGT) were measured. Results showed that there was significant difference between germination indices at different harvesting times. There was also significant difference 5 between germination indices in canola cultivars. Mean Germination Time was the maximum in first harvest and germination index, germination rate, energy of germination and vigor index had the highest values in the fourth harvest. Hyola401 cultivar had the most vigorous germination and seedling growth than the rest.