Research The Treatment Of Exogenous Homone On The Flowering Of Broccoli

The experiments took medmaturity broccoli hybrid named ’yuan-lv701’ as the objects to study the effects of exogenous substances on the vernalization and development of broccoli by spraying25,50,75,100mg·L-1gibberellin and20,60,100,140mg·L-1kinetin in vernalization stage (T1), bud differentiation critical period (T2) and the period before budding (T3). The results show that:1. The process of broccoli development could been promoted by spraying hormone in the period before vernalization, and the period of bud differentiation critical or the period before budding at spring or autumn. In the period before vernalization, each main development stage of spring broccli were shorten observably by spraying100mg·L-1gibberellin and100mg·L-1kinetin, so did the autumn broccoli by spraying100mg·L-1gibberellin and60,100mg·L-1kinetin. In bud differentiation critical period, budding stage, rapid growing stage and initial period of harvest were shorten observably by spraying25mg·L-1gibberellin and20mg·L-1kinetin in spring broccoli, so did the25～100mg·L-1gibberellin in autumn broccoli. In addition, in the period before budding, rapid growing stage and initial period of harvest were shorten observably by spraying25,75mg·L-1gibberellin and60,100mg·L-1kinetin in spring broccoli, so did the75,100mg·L-1gibberellin in autumn broccoli.2. The contents of endogenous gibberellin and kinetin would been influenced by spraying exogenous gibberellin or kinetin. The contents of gibberellin were increased at earlier stage and later stage of vernalization in spring broccoli and had kept a higher level at vernalization in autumn broccoli by spraying60mg·L-1kinetin, kinetin contents were increased dramatically in earlier stage of spring broccoli or later stage of autumn broccoli when exogenous kinetin was sprayed before vernalization. The contents of gibberellin were increased at the whole process of bud differentiation in spring broccoli or autumn broccoli, kinetin contents were increased in spring broccoli when exogenous kinetin was sprayed in bud differentiation critical period. The gibberellin contents could be increased by low concentration kinetin treating but decreased by high concentration kinetin treating in spring or autumn broccoli. In all, contents of endogenous CTK could be increased by spraying exogenous kinetin during the dud development when exogenous kinetin was sprayed in budding stage.The endogenous gibberellin and kinetin contents could be increased under100mg·L-1 gibberellin at earlier stage and later stage of vernalization in spring and autumn broccoli when exogenous gibberellin was sprayed before vernalization. while exogenous gibberellin was sprayed in bud differentiation critical period, endogenous gibberellin and kinetin contents of spring broccoli could be increased under25mg·L-1gibberellin in bud differentiation process, so did the endogenous gibberellin contents of autumn broccoli under75mg·L-1gibberellin, but endogenous kinetin contents of autumn broccoli under75mg·L-1gibberellin was decreased in later process of bud differentiation. When exogenous gibberellin was sprayed in budding stage, endogenous GA3contents in earlier stage of dud development and endogenous CTK contents in later stage of dud development were inreased under25mg·L-1gibberellin of spring broccoli or75mg·L-1gibberellin of autumn broccoli.3. The ratio of soluble sugar/soluble protein of broccoli could be increased by praying gibberellin and kinetin in bud differentiation critical period or before duding stage. The soluble protein contents could be increased by the imporved concentration of gibberellin during bud differentiation, the effect of25mg·L-1treatment was best in all. The soluble sugar contents were increased by praying gibberellin or kinetin, and could be all on the rise during dud development period, the effect of100mg·L-1kinetin was best in all. In addition, the ratio of soluble sugar/soluble protein of broccoli were higher than CK during bud differentiation process by praying gibberellin and kinetin in bud differentiation period or before duding stage4. The invertase, nitrate reductase and glutamine synthase were significantly changed during flowering process in broccoli. The activity of invertase was increased under100mg·L-1kinetin or75mg·L-1gibberellin in vernalization. Activity of NR was declined for the first and then rising and effects of50mg·L-1gibberellin was best in all. However, glutamine synthase activity trended to increase. During the bud differentiation period, invertase and NR activity showed to rise first and then decline, bud differentiation could be promoted obviously under20mg·L-1kinetin. However, glutamine synthase activity showed to decline under100mg·L-1gibberellin. In budding development period, invertase activity showed to rise and budding development could be promoted obviously under20mg·L-1kinetin or50mg·L-1gibberellin. NR activity showed to declined and could be promoted obviously under100mg·L-1kinetin or gibberellin. In addition, glutamine synthase activity showed to rise first and then decline, and could be promoted under20mg·L-1kinetin or100mg·L-1gibberellin.5. The yield of broccoli was increased significantly under20～140mg·L-1kinetin or25,50mg·L-1gibberellin before budding stage, so did the20～100mg·L-1kinetin or25mg·L-1gibberellin in bud differentiation critical period. However, yield of broccoli could be decreased significantly except60mg·L-1kinetin before vernalization. In addition, yield of autumn broccoli was decreased obviously under each gibberellin or kinetin treatments in three growth period, except25,50mg·L-1gibberellin treatings before vernalization.