Floral Differentiation Process Of Jiyan No.9and Its Changes Of Related Enzymes Induced By Low Temperature

The experiment use the main push varieties Jiyan No.9in Jilin as test material,studying flower bud growth and development process of different leaf age tobacco in different hypothermia,and analyze variation between flower bud differentiation and IAA catabolic associated enzymes and protective enzymes,through artificial climate chamber artificially controlling the temperature and take stereo microscope observation.The results show that:in the field agronomic traits, the cold-induced6-leaf stage tobacco prone to early flowering phenomenon,expressed as the number of leaves dropping,the3-leaf stage and CK did not occur early flowering phenomenon.The number of tobacco bud and bud rate survey shows that the number of low squaring is the most of6-leaf stage under cryogenic treatment, cryogenic treatment and exist significant differences,CK’s budding overall postponed4d compared with the6-leaf stage treatment;From stereo microscope observation,the flower bud differentiation is divided into6periods, and buds of Jiyan No.9begin to differentiate at about36day after transplanting when6-leaf stage,flower bud differentiation has basically ended when50d after transplanting,3-leaf stage and CK finish flower buds about53d after transplanting; In the flower bud differentiation process,variation of IAAO activity of CK and low temperature are almost the same,showing an upward trend after the first drop,reaching the lowest value when44d after transplanting, cryogenic processing activity was slightly higher.POD activity of low temperature processing and CK all showed a downward trend after the first rising,but time of reaching the peak of activity varies,respectively44d and51d.However,SOD and CAT activity variation was first increased and then decreased, its activity reached peak when51d,CK is relatively lower.To sum up,6-leaf stage is more sensitive to temperature than3-leaf stage under cold-induced,and the longer treatment duration of6-leaf stage, the more obvious the flower bud differentiation in advance.The three-leaf law contrary; In flue-cured tobacco bud differentiation process, Both the shoot tip differentiation examination results,and squaring time, tobacco grown process of6-leaf stage is3-5d than3-leaf stage and CK under cryogenic treatment;From buds begin to differentiate to budding takes about15d of Jiyan No.9.In short,6-leaf stage of tobacco continues9d low temperature processing, early flowering phenomenon is most obvious, followed by6-leaf stage continuous6d low temperature processing.