In order to explore the regulatory effect of exogenous hydrogen sulfide（H2S） on the levels of organic acids and hormones in plants under saline-alkali stress， naked oats（Avena nuda） were used as materials to study the effect of spraying 50 μmol·L-1 H2S donor sodium hydrosulfide（NaHS） solution on the contents of organic acids and hormones in leaves and yield traits under 3.00 g·kg-1 saline-alkali stress. The results showed that saline-alkali stress significantly increased the contents of succinic acid， butenedioic acid， malic acid， glucuronic acid and total organic acids， respectively， but significantly decreased the contents of pyroglutamic acid， jasmonoyl-isoleucine（JA-Ile）， trans-zeatin（tZ） and N6-（Δ2-Isopentenyl） adenine（iP） in leaves respectively. Under saline-alkali stress， spraying NaHS solution significantly increased the contents of 3-Hydroxy-3-methylglutaric acid， indole-3-acetic acid（IAA）， gibberellin A7（GA7）， methyl jasmonate（MJA）， iP and IAA/ABA ratio， respectively， but significantly decreased the contents of glucuronic acid， gibberellin A3（GA3）， gibberellin A4（GA4）， total gibberellins（GAs）， 1-aminocyclopropanecarboxylic acid（ACC） and ACC/ABA ratio respectively， while it had no significant effect on the contents of succinic acid， butenedioic acid， malic acid， citric acid， malonic acid， pantothenic acid， nicotinic acid， pyroglutamic acid， suberic acid， phenylpyruvic acid， total organic acids， gibberellin A1（GA1）， jasmonic acid（JA）， JA-Ile， abscisic acid（ABA）， tZ， trans-zeatin-riboside（tZR）， N6-（Δ2-isopentenyl） adenosine（iPA）， total jasmonic acids（JAs）， cytokinin（CTK） and the ratios of GAs/ABA， JAs/ABA and CTK/ABA respectively. The principal component analysis showed that spraying NaHS solution significantly increased the contents of organic acid 3-hydroxy-3-methylglutaric acid and hormones MJA， GA7， tZ and IAA in leaves of naked oat under saline-alkali stress by 14.31%， 41.83%， 50.00%， 22.97% and 13.02%， respectively； while the contents of organic acids nicotinic acid， glucuronic acid and hormones GA4， ACC， tZR and GA3 were significantly decreased by 16.00%， 23.87%， 73.53%， 32.72%， 50.00% and 33.91%， respectively. In addition， the application of NaHS solution reduced the 1 000 grain weight of naked oat under saline-alkali stress by 5.91%， while spike number， boll number per spike， spike grain numbers and grain yield were increased by 2.19%， 9.70%， 61.60% and 52.83%， respectively. These results indicated that exogenous H2S participates in the regulation of organic acid and hormone levels of naked oat under salt-alkali stress， which could enhance the ability of naked oat to adapt to salt-alkali stress.
%U https://bbr.nefu.edu.cn/EN/10.7525/j.issn.1673-5102.2023.01.009