Details

Autor(en) / Beteiligte

• Carrera, Esther
• Bou, Jordi
• García‐Martínez, José Luis
• Prat, Salomé

Titel

Changes in GA 20‐oxidase gene expression strongly affect stem length, tuber induction and tuber yield of potato plants

Ist Teil von

• The Plant journal : for cell and molecular biology, 2000-05, Vol.22 (3), p.247-256

Ort / Verlag

Oxford, UK: Blackwell Science Ltd

Erscheinungsjahr

2000

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• Summary Gene StGA20ox1 encoding potato GA 20‐oxidase is expressed to relatively high levels in leaves and regulated by daylength. To investigate whether this gene is involved in photoperiodic regulation of tuber formation, we have obtained transgenic potato plants expressing sense and antisense copies of the StGA20ox1 cDNA. Over‐expression of this cDNA resulted in taller plants that required a longer duration of a short day photoperiod (SD) to tuberize. Tubers from these plants had a decreased time of dormancy and developed sprouts with elongated internodes. Plants expressing antisense copies of the StGA20ox1 cDNA had shorter stems, a decreased length of the internodes and tuberized earlier than control plants, showing increased tuber yields. Antisense inhibition of this gene had no visible effect on the time of dormancy of the tubers, although at the end of dormancy these formed sprouts with shortened internodes. Decreased levels of endogenous GA20 and GA1 were detected in the apex and first leaves of the antisense lines. These results demonstrate the involvement of the GA 20‐oxidase activity encoded by StGA20ox1 in the control of stem elongation and in tuber induction but not in tuber dormancy, indicating that the latter may be regulated by another member of the gene family.