Study On Breeding And Application Of Ilex Verticillata In Landscape

Ilex verticillata is a kind of holly deciduous shrub or small tree family Aquifoliaceae, commonlyknown as winterberry and whorl holly as well as American holly. It is native to the northeast of the USA,and growing in low forests, swamps, and river bottoms in the wild. The tree is beautiful, and thebranches of the tree are filled with red fruits which are long-term persistent in the fall and winter. Thefruiting for five months, and it is a great tree to build urban plant landscape in the fall and winter.Biological characteristics, breeding techniques of cuttings, techniques of potted and landscapeapplication of Ilex verticillata were studied and researched in this thesis. All trials were limited toHangzhou Runtu technology Co. and the conclusions were:(1) The phenophase of Ilex verticillata was obvious. And its germination period for vegetative budswas limited to the early March to mid-to-late March around, and the germination period for flower budswas limited to the mid-to-late April to early May. Its full-bloom stage was focus on May10and on May20around. The period of fruit coloring was limited to all the September to early October around. Theperiod of fruit dropping were obviously different, and the fruits were fall off in the mid-to-late March atthe latest. The period of leaves color change was focus on mid-to-late October, and the abscission periodwas mostly in November and December. The indexes of growth and development were observed.Results indicate that the growth trend of indexes of plant height and crown breadth and the length ofannual branchlets was accord with S-curve model which appears slow-fast–slow. The increase of thenumber of the foliage was focus on April1to May21, which was not accord with S-curve model.(2) Effects of different kinds and different concentrations of rooting reagents on the rooting ofannual cuttings of Ilex verticillata were investigated. The best combination of the factors was thatone-year-old root cuttings soaked in IBA with500mg·L-1, and the rooting rate could be as high as97.69%.(3) Perlite and peat and vermiculite were mixed in different proportions of12kinds of substratefor burgeon cutting contrast test. The results indicate that the best substrate for cutting of Ilexverticillata was M11(15%perlite+35%peat+50%vermiculite), and the rooting rate was63.89%, andthe mean root length was4.05cm, and the root effective indexes was as high as0.65.(4) Turfy soil, carbonized rice husk, washed and dried cow-dung and yellow soil were taken asthe original medium according to the different proportion for potted cultivation. The observations ofindex of aboveground and underground were synthesized, and the best cultivation medium was theNo.4(50%Turfy soil+20%washed and dried cow-dung+20%carbonized rice husk+10%yellow soil).The No.3(80%washed and dried cow-dung+20%yellow soil) was more suitable considering from theaspects of economy.(5) The effect of different concentrations of PP333to treat the potted Ilex verticillata by twomethods of application (foliage spray and root drench) were investigated. The results showed that thedifferent treatments of PP333had significant influence and were different on the growth of potted Ilexverticillata. And the inhibiting effect of same concentrations of PP333by method of foliage spray was more apparent than root drench. The best treatment combination was5000mg·L-1of PP333applied asfoliage spray and10000mg·L-1of PP333applied as root drench. And the dwarfing effect of pottedI.verticillata watered with1000mg·L-1of PP333in September,2012was better than watered in March,2013. And its dwarfing effect had no obvious relation with ages of potted I.verticillata.(6) The shading test shew that the shading rate of75%contributed to reduce rate of defoliation andfruit abscission. The fruit vertical and transect diameter were different degrees of increase at the sametime. In addition, the time of fruit coloring was obviously delayed by shading treatment.(7) Combined the application of Ilex verticillata in abroad, Ilex verticillata used in cut flowers,artistic flowers, potted plants and landscape application were discussed.