In Taiwan, the early harvesting of young ginger is a cultivation technique for domestic ginger, which can be harvested early by forced sprouting. At present, ethylene is used as the sprouting agent. Despite its favorable sprouting effect, the technique can still be improved. Experimental results revealed that 1% citric acid, 300-ppm and 450-ppm ethephon treatments effectively facilitated the formation of 2.4, 2.4, and 2.6 large buds (diameter of ≥ 1 cm), respectively, in the rhizome. The stems and leaves of the ginger seed rhizomes that were subjected to forced sprouting emerged from the soil one month after planting, and emergence rates of 46.7% and 83.3% were achieved using citric acid and ethephon, respectively. Although the fresh weight of semi-matured ginger rhizomes obtained by forced sprouting treatment was lower, the results can still provide a reference for the early harvest of young ginger in Taiwan. Among the examined gingers, semi-matured ginger that was subjected to 50-ppm GA 3 forced sprouting treatment exhibited the most favorable growth, and the average weight of its rhizomes reached 1,567 g, which was not significantly different from the weight obtained by conventional cultivation, but significantly greater than that obtained by other treatments. The GA 3 forced sprouting treatment was not very effective, but it had an excellent effect on improving the yield of semi-matured ginger rhizomes. In the future, this treatment will be conducive for the production of semi-matured or matured ginger.

Seeds of some winged bean varieties have low germination due to the presence of water-impermeable hardseeds. Seeds of ‘Taitung No.1’ winged bean had only 31% germination because the remaining 69% of seeds had a water-impermeable seedcoat. Sandpaper abrasion and sulfuric acid immersion for 15 and 25 min effectively removed hardseededness of the seeds, resulting in more than 89% germination. As seed moisture content (MC) decreased from 14.8% to 7%, the percentage of seeds with a water-impermeable seedcoat increased. Seed lots with 14.8%, 11%, 9%, and 7% MC had 7%, 38%, 56%, and 78% of hardseeds, respectively, on day 7 in the germination test. It was found that the hilum was responsible for water loss from the whole seed, and the seedcoats began to become water-impermeable at 12% MC. The lens and micropylar regions were initial water entry sites in the Vaseline-blocking experiment.

Winged bean seeds require imbibition treatment to ensure fast and uniform germination. Seed soaking has been commonly used; however, it is unclear if this is a safe method for winged bean seeds. Solid matrix priming (SMP) is an imbibition treatment that combines seeds, a matrix and water in a specific ratio. It allows seeds to imbibe under controlled water uptake. We investigated the effect of imbibition treatments on seed germination of white winged bean. Soaked seeds had significantly reduced germination and emergence as a result of imbibition injury due to rapid imbibition. SMP at a seed: vermiculite: water ratio of 7:12:9 (w/w/w) was the most effective treatment that allowed seeds to imbibe slowly without the occurrence of imbibition injury. SMP significantly reduced the mean germination time from 4.63 days to 2.01 days, and mean emergence time from 7.21 days to 5.78 days, compared to the control, as well as having a high germination rate of 98% and uniform emergence. The fast imbibition rate of white winged bean seeds was likely the result of cracks present on the permeable seed coat.

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