Open AccessModification of gibberellin biosynthesis in the grafted apple scion allows control of tree height independent of the rootstock
Author(s) -
Bulley Sean M.,
Wilson Fiona M.,
Hedden Peter,
Phillips Andrew L.,
Croker Stephen J.,
James David J.
Publication year - 2005
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/j.1467-7652.2005.00119.x
Subject(s) - rootstock , biology , gibberellin , tree (set theory) , botany , mathematics , combinatorics
Summary The availability of short stature apple scions that required minimal applications of chemical growth retardants and could be used with a range of rootstocks would be of considerable benefit to fruit growers. We have suppressed the expression of a gene encoding the gibberellin (GA) biosynthetic enzyme GA 20‐oxidase to reduce the levels of bioactive GAs in a scion variety, resulting in significant reductions in stem height. Application of GA 3 reversed the effect. The scion remained dwarfed after grafting on to normally invigorating rootstocks, whilst control plants of the same cultivar displayed the expected vigour when grafted on to these rootstocks. This approach could be applicable to any perennial crop variety, allowing dwarf trees to be obtained on any available rootstock or on their own roots without the need for chemical growth retardant application. In effect, seedlings that are well suited to local conditions (drought, salinity) could be employed as tree rootstocks, as could existing rootstocks valued for characters other than vigour control, such as pest and disease resistance.