Explain why GA³ is applied to …

The prospects for enhancing flowering, for the purposes of breeding and seed supply, appear good, particularly for members of the Pinaceae. The most successful techniques involve the application of the gibberellin A4 and A7 mixture combined with cultural treatments such as drought, root pruning or girdling. There is scope for these techniques to be used in outdoor seed orchards but more particularly with container-grown plants in polythene houses. Less research has been published on enhancing flowering in broadleaves (angiosperms) though there has been considerable attention to factors affecting blossom and fruit development. Techniques that encourage rapid vegetative growth so that plants quickly reach a certain minimum size may be the most promising to promote flowering of broadleaves. Avenues for further research are considered.