| Abstract: | The purpose of this study was to investigate the effects of various presowing treatments on the germinability (final germination percentage) and germination rate of loquat seeds in order to increase seedling production in nurseries
(applied research) as well as provide answers for important physiological issues
related to loquat seeds and their seed coat (basic research). Three experiments
were carried out with various pre-sowing treatments. These treatments included
full or partial removal of seed coat (perisperm), partial cutting of cotyledons as
well as moist chilling at 5°C for 13 days and/or soaking the seeds in water or
250 ppm gibberellic acid (GA3) solution for 24 h. According to the results, cotyledons excision resulted in delayed germination, regardless of the presence or
absence of the seed coat in comparison with the decoated seeds that demonstrated
the highest germination rate amongst them. In addition, even the partial excision
of seed coats affected positively both the germinability and the germination rate,
compared to the control-intact seeds. Furthermore, control-intact seeds had a
higher germination percentage when exposed to moist chilling independently of
the application or not of gibberellin; while the combination of gibberellin application and moist chilling improved both the percentage and the rate of germination
of decoated seeds. In conclusion, the role of perisperm (seed coat) in the germination procedure of loquat seeds seems to be important, indicating the existence of
seed coat-imposed dormancy on loquat seeds. Finally, the existence of a mild
endogenous embryo-dormancy on loquat is also discussed. |
