Effects of H2S and rhizobia on AsA-GSH cycle in
soybean plants under water deficiency
With the decrease of water content, the GSH content was no apparent
increased by Q8 and Q8 + NaHS treatments under MW and SW conditions, and
not obvious differences between the Q8 and Q8 +NaHS treatments (Fig.
7A). However, water deficiency caused an obvious change in GSSG content
under four treatments. Compared with control, the GSSG content was
substantially increased by Q8 and Q8+NaHS treatments under other three
water conditions. Moreover, with the decrease of water content, the GSSG
content had an obvious increase trend under Q8+NaHS treatment (Fig. 7B).
Interestingly, Q8 and Q8+NaHS treatments increased the GSSG content
under water deficiency in leaves, the ratio of GSH/GSSG was
significantly reduced by two treatments (Fig. 7C).
In addition, the AsA content in control treatment was notably increased
under SW condition compared with NW condition. With the decrease of
water content, the AsA content by Q8 and Q8+NaHS treatments displayed a
tendency to increase initially and then decrease. Under SW condition,
the AsA content showed a significant decrease under Q8 and Q8+NaHS
treatments compared with control (Fig. 7D). Compared with control, the
DHA content was substantially reduced by Q8 and Q8+NaHS treatments under
NW and MW conditions, but the change under SW condition was not obvious
(Fig. 7E). With the decrease of water content, the DHA content was
greatly increased by Q8 and Q8+NaHS treatments, while showed a downward
trend under control treatment (Fig. 7E). As a result, we found that
under NW and MW conditions, the AsA/DHA ratio of the four treatments had
similar changing trends, and the AsA/DHA ratio of Q8 and Q8+NaHS
treatments was much higher than that of control treatment. In addition,
the AsA/DHA ratio of control treatment was significantly higher than
other treatments under SW condition (Fig. 7F).
In addition, the MDHAR activity was affected by water deficiency under
the four treatments, and Q8+NaHS treatment promoted MDHAR activity in
the leaves under SW condition (Fig. 7G). Interestingly, the DHAR
activity of Q8 and Q8+NaHS treatments was appreciably higher than that
of control treatment under any water content. With the decrease of water
content, the DHAR activity of leaves by the four treatments decreased to
varying degrees. (Fig. 7H). The changes of GR activity among the four
treatments of SW condition were similar to those of NW condition. The GR
activity of Q8 and Q8 +NaHS treatments were much higher than that of
control treatment (Fig. 7I).