The free putrescine (Put) content, the hydrogen peroxide (H 2 O 2 ) content and the polyamine oxidase (PAO) activity in roots of Malus hupehensis Rehd. var. pin
The aldehyde dehydrogenase (ALDH) superfamily of NAD(P)+-dependent enzymes, in general, oxidize a wide range of endogenous and exogenous aliphatic and aromatic