澳大利亚生产伏令夏橙的一个严重问题是隔年结实,需要一可靠的措施来克服大小年。由于赤霉素可以抑制柑桔开花,便在1971年进行田间试验。在新南威尔士,莫累河灌溉区的阳科一个果园,选取十四年生,而历年大小年结实显著的“Late”伏令夏橙为试材(多数的砧木为枳,少数砧木为枳 A serious problem with the production of summer orange in Australia is that it is strong every other year and that a reliable measure is needed to overcome the size of the year. Since gibberellin can inhibit citrus flowering, a field experiment was conducted in 1971. In New South Wales, an orchard in the Yalong River irrigation area of ​​the Murray River, fourteen-year-olds were selected, and “Late” valerian summer oranges were significantly harvested over the years. Most of the rootstocks were trifoliate oranges and the minority rootstocks were trifoliate orange