Effects of methyl jasmonate and abscisic acid on anthocyanin biosynthesis in callus cultures of red-fleshed apple (Malus sieversii f. niedzwetzkyana)

We researched the effects of methyl jasmonate, abscisic acid, and a combination of the two on anthocyanin metabolism in callus material induced from the leaves of a red-fleshed apple individual, which was a hybrid offspring of Malus sieversii f. niedzwetzkyana and Malus domestica cv. 'Fuji'. The results showed that methyl jasmonate promoted anthocyanin accumulation with increasing methyl jasmonate concentration in the range of 10(-6) to 10(-3) mol/L. Abscisic acid significantly inhibited anthocyanin biosynthesis, and its inhibitory effect was highest at 6 mu mol/L among all treatments. In addition, methyl jasmonate alleviated the inhibitory effect of abscisic acid on anthocyanin biosynthesis. Gene expression analysis indicated that methyl jasmonate induced the expression of MdMYB9 and MdMYB10, which are positive regulator of anthocyanin biosynthesis, and inhibited MdMYB11 expression. It also upregulated the expression of the anthocyanin structural genes MdCHS, MdF3H and MdUFGT. Abscisic acid inhibited the expression of MdMYB3 and MdMYB10, as well as the expression of the structural genes MdF3H, MdDFR, MdLDOX and MdUFGT. Methyl jasmonate relieved the inhibition by abscisic acid by decreasing the expression of MdMYB11 and MdMYB16, and increasing the expression of the anthocyanin regulatory genes MdMYB3, MdMYB9 and MdMYB10, and the structural genes MdCHS, MdDFR, MdF3H and MdUFGT. Thus, we elucidated the roles of methyl jasmonate and abscisic acid in the regulation of anthocyanin production at the gene transcription level.