elongation; subsequently, auxin supports stolon swelling due to cell expansion, and cytokinin stimulates cell division for rapid thickening growth. A more recent study by Faivre-Rampant et al. (2004) reported that auxin response factor 6 (ARF6), a key regulator of auxin-responsive genes, is involved in tuberization and tuber dormancy release in potato. The expression of ARF6 was shown to be repressed by auxin [naphthalenacetic acid (NAA)] treatment, and its steady-state expression level decreased by 10-fold upon transition from a longitudinal (transverse cell division) to a lateral (longitudinal cell division) stolon expansion. Thus, auxin most probably plays a role in tuber formation in potato.It was demonstrated that the endogenous IAA level gradually increased during the early stage of storage root development (Fig. 5), suggesting that the early stage of
đang được dịch, vui lòng đợi..