Studies On The Senescence Process Of Lycoris Longituba Leaves

Lycoris were economic value of chincherinchee, They were valuable as ornamental and medical plants with their flowers and leaves. The growth period of their leaves was short, focused in the end of spring and beginning of summer. This characteristic was different from other bulb plants. Lycoris longituba was selected as experimental material. This paper had studied on the change of conformation during the senescence process of Lycoris longituba leaves and the effect of different temperature on the senescence process of Lycoris longituba leaves. It analyzed the change of proteins during the senescence process of Lycoris longituba leaves by SDS-PAGE and IEF/SDS-PAGE, which was basic research on molecule mechanism of leaf senescence. At the same time, controlling the senescence process of Lycoris longituba leaves was done by hormone, in order to defer the time of the leaf senescence and prolong the period of leave growth. The results as follows:(1)The decrepit rules of Lycoris leaves were: the senescence of all leaves incarnated that they turned yellow from outside to inside; to the single leaves, the main type of senescence was that it was from tip to the edge gradually, and then went to middle nervation and to the base of leave finally. There was affinity between temperature and the senescence of lycoris longituba. temperature of 30 degree could restrict leaves growth, accelerate them senescence, and it was near the outside temperature. Therefore, we considered that the senescence of Lycoris was restricted by high temperature, and Lycoris could not forbear the heat commendably.(2) Using GA₃ and 6-BA could delay leaves senescence of lycoris longituba. 20mg/l of GA₃ using separately was able to obtain the best effect, so was the 30mg/l of 6-BA. 10mg/l of GA₃ mixed with 15mg/l6-BA was better than using one of them solely, maybe the reasons of which was that GA₃ and 6-BA acted each other and recruited each other.(3) Soluble protein content descended the process of lycoris longituba leaf senescence.The SDS-PAGE and IEF/SDS-PAGE were analyzed the change of composition and distributing of proteins. The richness of the most of protein spots descended during the senescence process of Lycoris longituba leaves, and distributing was similar. The protein spot (46.5kD,pI 5.2),(47.0 kD,pI 5.2),(22.6 kD,pI 5.6),(19.2 kD,pI 5.5) and the molecular weight of 59.0kD,46.1 kD,53.1 kD had close relationship with leaf senescence. The protein spot (19.2 kD,pI5.5) probably started up the process of leaf senescence.