淹水条件下平邑甜茶根系NO生成及外源硝酸钠对其影响

以2年生平邑甜茶(Malus hupehensis)为试验材料，研究了淹水条件下平邑甜茶根系一氧化氮(NO)的生成规律以及外源硝酸钠(NaNO₃)对NO生物合成的影响.结果表明：3～9 d的淹水处理显著提高了平邑甜茶根系NO生成量；在12 d内，随着淹水时间延长，根系NO生成量、硝酸还原酶(NR)、一氧化氮合酶(NOS)活性和丙二醛(MDA)含量均先上升后下降.10 mmol·L^-1NaNO₃显著抑制了淹水条件下根系MDA含量和NOS活性的提高，但NR活性增强；淹水期间，根系NO生成量在NaNO₃处理的前3天提高，处理第6天后显著降低.

Nitric oxide production in Malus hupehensis roots under waterlogging and the effects of exogenous NaNO3 on this production

Taking two-year old Malus hupehensis as test material, this paper studied its root nitric oxide (NO) production under waterlogging, and the effects of exogenous NaNO₃ on this production. Waterlogging for 3-9 days promoted the NOproduction significantly. Within the 12 days of waterlogging, the NO production, nitrite reductase (NR) and nitric oxide synthase (NOS) activities, and malondialchehyche (MDA) content in roots increased first, and decreased subsequently. Under waterlogging, the application of 10 mmol NaNO₃·L^-1 inhibited the increase of MDA content and NOS activity while improved the NR activity significantly. After applying NaNO_3, the root NO production increased in the first three days, but decreased significantly after the 6th day.