Gibberellic acid(3) modifies some growth and physiologic effects of paclobutrazol (PP333) on wheat

Gibberellic acid(3) (GA(3)) modification of some growth and physiologic effects of paclobutrazol (PP333) was studied by applying PP333 alone and in combination with GA(3) at the tillering stage of wheat. Results showed that GA(3) weakened the effect of PP333 on tillering and shortening the plant, increased the dry matter accumulation of different tillers, improved plant nitrogen metabolism by favoring nitrogen translocation into tillers at late growth stage, and stimulated tiller development. All of these reduced the difference in spike weight among tillers and the main stem. Compared with control, there were more spikes per plant and fewer grain per spike in the PP333 treatment, but all yield components developed positively in the treatment consisting of the mixture of GA(3) and PP333.