Studies of short-chain fatty acids in apple seed dormancy.

摘要

The inhibitory activity of short chain fatty acids in apple (c.v. Northern Spy) embryo germination was investigated. Their biological activity when added exogenously was found to be dependent on chain length. Fatty acids with nine and ten carbon atoms were the most inhibitory. The concentrations effective in inhibition were in the millimolar range. No synergistic effects were detected when two short chain fatty acids were incorporated simultaneously. A mixture of gibberellins;In interaction studies between the time of stratification and nonanoic acid, it was found that the inhibition of nonanoic acid was less when the embryos received more stratification. When nonanoic acid was added at different stages of stratification, the earlier the addition of nonanoic acid, the more the inhibition.;Changes in endogenous short chain fatty acids in different apple seed parts (seed coat, nucellus membrane, and embryo) during stratification and seed development were examined. The existence of the short chain fatty acids investigated in this thesis research was confirmed by Gas-Chromatography Mass Spectrometry. The nucellus membrane contained the highest concentration of short chain fatty acids. However, the concentration of these substances in various seed parts or on a per seed basis during stratification were much lower than one millimolar, too low to be inhibitory. Short chain fatty acid changes during stratification were not correlated with the release from dormancy. In studies of young developing seeds, the short chain fatty acid concentration was also low. It seems unlikely that these substances have a significant role in the development of dormancy which occurs during the maturation of the seed.