02362naa a2200253 a 450000100080000000500110000800800410001910000140006024501020007426000090017650001560018552014550034165000130179665000170180965000290182665000150185565000220187065300310189265300280192365300260195165300240197770000150200177300920201619816322017-07-04       2013    bl uuuu     u00u1 u    #d1 aIQBAL, M.  aSalt tolerance and regulation of gas exchange and hormonal homeostasis by auxin-priming in wheat.  c2013  aTítulo em português: Tolerância ao sal e regulação de trocas gasosas e da homeostase hormonal pelo condicionamento osmótico com auxinas em trigo.  aThe objective of this work was to assess the regulatory effects of auxin‑priming on gas exchange and hormonal homeostasis in spring wheat subjected to saline conditions. Seeds of MH‑97 (salt‑intolerant) and Inqlab‑91 (salt‑tolerant) cultivars were subjected to 11 priming treatments (three hormones x three concentrations + two controls) and evaluated under saline (15 dS m‑1) and nonsaline (2.84 dS m‑1) conditions. The priming treatments consisted of: 5.71, 8.56, and 11.42 × 10‑4 mol L‑1 indoleacetic acid; 4.92, 7.38, and 9.84 × 10‑4 mol L‑1 indolebutyric acid; 4.89, 7.34, and 9.79 × 10‑4 mol L‑1 tryptophan; and a control with hydroprimed seeds. A negative control with nonprimed seeds was also evaluated. All priming agents diminished the effects of salinity on endogenous abscisic acid concentration in the salt‑intolerant cultivar. Grain yield was positively correlated with net CO2 assimilation rate and endogenous indoleacetic acid concentration, and it was negatively correlated with abscisic acid and free polyamine concentrations. In general, the priming treatment with tryptophan at 4.89 × 10‑4 mol L‑1 was the most effective in minimizing yield losses and reductions in net CO2 assimilation rate, under salt stress conditions. Hormonal homeostasis increases net CO2 assimilation rate and confers tolerance to salinity on spring wheat.  aSalinity  aSeed priming  aRegulador de crescimento  aSalinidade  aTriticum Aestivum  aCondicionamento de semente  aPlant growth regulators  aRegulação estomatal  aStomatal regulation1 aASHRAF, M.  tPesquisa Agropecuária Brasileira, Brasília, DFgv. 48, n. 9, p. 1210-1219, set. 2013.