苹果花芽孕育机理的探讨

花芽孕育期，以环剥、多效唑＋环剥和ＧＡ３处理“红富士”苹果树，成花效应以多效唑＋环剥处理为最高（＋６８４％）。花芽孕育起动时，促花处理的短枝顶芽内ＩＡＡ、ＺＲ含量和ＩＡＡ／ＧＡｓ、ＺＲ／ＧＡｓ的比值均明显提高。在花芽孕育完成过程中，促花处理的短枝叶内淀粉含量、Ｃ／Ｎ比，芽内ＺＲ、ＩＡＡ含量和ＺＲ／ＧＡｓ明显提高，ＧＡｓ则明显下降。

Study on the Mechanisms of Flower Bud Induction in Apple Tree

Five-year-old 'Red Fuji' appletree(Maha domestica Mill ) were used asmaterials to test for the effect of treatmentS of paclobutrazol (Pacl ),girdling, girdling Pacl. and GA3 onthe contents of nitrogen and carbohydrates in spur leaves and of endogenoushormones in buds. The results showedthat the effects of the treatmentS to increase flower bud formation were in theorder of girdling Pacl. ( 648 % ) >girdling ( 534%) > Pacl. ( 154%). At the beginning of flowerbud induction, the contentS of IAA andZR (Fig. 4), and ratio of IAA/GA. orZR/GA. (Fig. 5) were significantly increased in spur buds, while the ratio ofIAA/GA. with various flower--promoting or-inhibiting treatments were muchhigher and was correlated with the Percentage of flower bud formation. ZR/GA. ratio, however, was negativelycorrelated with the Percentages of flower formation of which girding treatment, giving high Percentage of theflower formation resulted in a lowerZR/GA. ratio than treatment with Pacl., which gave a low Percentage offlower bud formation. At the completing phase of flower bud induction,starch content and C/N ratio (Fig. 3)and the contentS of ZR and IAA, andZR/GA. ratios in spur bud were remarkably increased, while GA. contentin spur bud was decreased by girdling Pacl., girdling and Pacl. treatmentS.The above parameters for all the flower--promoting or--inhibiting treatmentSwere changed in the opposite directionto the Percentage of flower formation,except the C/N ratio.