Study On Hydroponic Induction Of Ixora Chinensis Based On Layering

In order to explore new woody plant hydroponics methods and provide data support for the cultivation of woody hydroponic plants,the I.coccinea’Dwarf’ was used as test material in this study,which combined the air layering with hydroponic.It is mean that induced root by layering and then transfer to hydroponics.Test results show that:(1)At the stage of layering,the effects of date,time,matrix and hormones for layering were studied.The results showed that among all the factors had a significant effect on rooting of I chinensis by air layering.Among them,the layering date in the all was the best for layering effect on rooting and the rooting index was 12 times of the layering in the spring;The best rooting effects was observed on 150 mg/L NAA;The optimum time and matrix for layering were respectively 35 day and peat.(2)After hydroponic culture,the roots of all treatment layers had growth,indicating that the roots of the layering can adapt to the hydroponic environment.The root growth was highest in the fall,and the lowest in the spring;The treatment of layering 35 days was highest increase in root system after hydroponics.In the matrix treatment,the root growth was lowest after sawdust was treated with hydroponics,which was significantly lower than other treatments,and the difference in the remaining treatments was not significant;After the hydroponic treatment with NAA concentration of 200 mg/L,the roots showed negative growth,while the other treated roots had growth,and the treatment with 150 mg/L NAA had the highest increase;The hydroponics medium had a significant effect on the growth of the roots of the I.chinensis.The root growth was the highest in the peat treatment,and the root growth in the water substrate was the lowest.(3)Physiological indicators were change after hydroponics culture,except that the MDA was increases,Pro,soluble sugar and the relative water content of leaves were declining.In addition to the significant decrease in Pro content,there was no significant difference in other indicators,indicating that the I.chinensis can adapt to hydroponic culture.(4)Different rooting time and rooting quality of I.chinensis were different under different cultivation conditions.The rooting initiate time of layering is shorter than that of substrate culture or hydroponics,10 days and 20 days in advance respectively.The average root length in the layering treatment is significantly longer than other two treatments’.The adventitious roots were mainly derived from dermis and were thick,white and long,and their secondary root system is well developed with lots of root hair.The root system of plant cultured in soil and water were mainly derived from callus.The root of plant cultured in soil is more compact than the layering propagation’s.The root system of plant cultured in soil have the developed secondary root and root hair.The root system of plant cultured in water are slender and soft,with less secondary roots and no root hair.(5)The layer root system and the matrix bacon system are similar in microstructure.Them root epidermis is thick,the cells are arranged closely,the structure of each part is complete,the apical cells are smaller,the cytoplasm is thicker,and the cell wall is thicker.After hydroponics,the epidermis of roots of plant in layering cultures and hydroponic were thin.The cortical cells were loosely arranged,the cells are larger,the cell walls are thinner,the cytoplasm is shallow,and there are obvious gaps or air cavities between the cells,forming an aerenchyma that resembles hydroponic plants.It indicated that the plant of the layering hydroponics formed some root structure to adapted the hydroponic environment,which is conducive to the growth of the layer in the hydroponic environment.