Effects Of Three Plant Growth Substances On The Growth And Physiological Characteristics Of The Tabebuia Chrysantha Seedling

Choosing one-year Tabebuia chrysantha seedlings as experimental materials, using orthogonal experimental method in order to research the effect of three plant growth substances (GGR、IAA、PP333)have on Tabebuia chrysantha seedlings growth, physiological and photosynthetic characteristics. After determination test part of growth,physiological and photosynthetic index to carry out the comprehensive analysis and evaluation. Screening the best combination of the plant growth substance combination. And preliminarary discussion the action mechanism of the plant growth substances on the Tabebuia chrysantha seedlings. Comprehensive analysis of the results are as follows:(1)Growth characteristics:different kinds of plant growth substances all could promoting growth of Tabebuia chrysantha seedling in its appropriate concentration. the best plant growth substance is GGR, it can significantly promote the growth of seedling height and ground diameter,and effective in increase biomass and promote the growth of root system organization, followed by IAA,once again for PP333.(2)Physiological characteristics:on the whole,different kinds of plant growth substances could affects the physiological of Tabebuia chrysantha seedlings. PP333 can reduce MDA content, GGR on seedling leaf free proline content decreased significantly; In addition, IAA on seedling leaf chlorophyll content and chlorophyll a/b value effect is remarkable, the influence of most treatment combination chlorophyll content than CK increase; GGR has obvious effects on SOD and CAT enzyme activity,it can eliminate seedlings peroxide in the body, so as to maintain normal physiological metabolism of plants.(3)Photosynthetic characteristics:different kinds of plant growth substances all could affects the photosynthetic indexs of the Tabebuia chrysantha seedlings.It can effectively enhance seedling average daily net photosynthetic efficiency, transpiration rate, stomatal conductance, decrease intercellular CO2 concentration, one of the best plant growth substance for IAA, followed by GGR, PP333 is once again.(4)The comprehensive quality evaluation:different kinds of plant substance all could enhance quality of the Tabebuia chrysantha seedling,but different kinds of plant growth substance has different effects. Take comprehensive quality evaluation of 16 groups of Tabebuia chrysantha seedling’s growth and physiological and photosynthetic indexes, the results for 11 processing (GGR400 mg·L-1,IAA 400 mg·L-1,PP333400 mg·L-1), the overall quality of the seedling is the best.