Abstract
Salt stress is a major reason for limiting the available arable land. This study investigated the physical manifestations of the responses of Arabidopsis thaliana wild type and phytohormonal mutants subjected to salt stress. Ethylene is a key stress responding, gaseous hormone that plays a major role in the growth of a plant. Therefore, the study also focused on ethylene's interactions with other hormones in response to salt stress, utilizing phytohormone mutants and standard ethylene measuring procedures. The phytohormonal mutants that were studied included plants with altered ethylene, abscisic acid, auxin, and brassinosteroid biosynthesis or perception.
The results of this experiment suggested that as the salt concentration increased,
the plant would have poorer growth. It also suggested that there might be
an optimum salt stress level under very low salt concentration. Since ethylene
interacts with various other hormones, it was difficult to conclude the relationships
between ethylene, salt stress and all the other hormones studied in this investigation.
However, based on the results of this study it can be concluded that in order
to produce salt stress tolerant plants one should use mutations not in one
phytohormone, but perhaps in few: The results of this experiment suggested
that one should use a combination of ABA resistance, ethylene insensitive
and BR overproducer mutations. Also, salt stress tolerant plants should not
be depleted in auxin biosynthesis; however more tests need to be carried out
on auxins. The knowledge gained from this study could lead to the development
of better genetically modified salt stress tolerant plants, which is a major
problem that plagues more than 35% of the world's arable lands.