A Research On The Influence Of Light Treatments And Density Dependence On The Cymbidium Hybridum's Growth

Cymbidium hybridum is one of the popular commercial potted flowers in global flower market.In accordance with cultural requirements of cymbidium hybridum in Guizhou area,this research deals with different analysis with conventional cultivation method to change the physiological and ecological conditions of cymbidium hybridum. In this way,the following aspects will be respectively investigated:each indication of its vegetative organ and reproductive organ,the daily record of temperature data to obtain effective accumulated temperature.By combining the density-dependence theory,reproductive allocation theory and growth rate,grey relational theory with biological statistics, the thesis studies the growth situation of flowering of cymbidium hybridum and makes a preliminary exploration on the feasibility of low-cost cultivation and how different methods influence the vegetative organ and reproductive organ of cymbidium hybridium in its flowering.The obtained results are as follows:1.Two kind of light treatments have a great influence on the amount of flowering plant,but the difference of the influence on its vegetative organ from these two treatments is not obvious.2.The seasonal growth dynamics of flower arrow takes the form of "S" curve and further analysis shows that the cubic fitting curve is best.Absolute growth rate is basically in step with relative growth rate and both exhibits monopeak curve,but there is little difference in time when negative growth rate appears.The seasonal dynamics of accumulation absolute growth rate and accumulation relative growth rate are both "S" curve shaped,and the cubic fitting curve is best as well.3.The number of flower bud has the same influence on the length of flower arrow,inflorescence,and flower stand and that influence has a tendency to increase.The length of flower stand is specifically embodied by the same rhythmicity between various internodes of the flower stands.The ratio of reproductive investment to inflorescence increases and it remains the same while enlarging the nether part of the flower stand.4.In reproductive and growing periods,cymbidium hybridium is obviously constrained by pot intensity.However,even if in such unfavorable conditions,it obtains more energy by increasing the leaf amount,leaf width,and leaf area in sexual reproduction period and uses the energy of pseudo bulb for storage so as to improve its reproductive ability.5.Based on the grey relational,the relation between the flower arrows of cymbidium hybridium in different growth periods and with different varieties and nine relative agronomic characters is analyzed.The analysis manifests the flower arrow diameter of cymbidium hybridium has the greatest influence on its growing speed.Next to it is the leaf length related with photosynthesis.The influence of leaf area,the biggest leaf width,the average leaf width,the number of leaf, the length of flower arrow and the number of buds is quite limited.The growth speed of flower arrow depends less upon the carbohydrate material contained in pseudo bulbs.According to the results,the author holds that the cultivation of cymbidium hybridium in Guiyang area should adopt less shade disposal or none shade disposal at all throughout the year.Plants with flower buds should be taken care of in a centralized way.Artificial light should be used to compensate for the shortage of sunshine days and low light intensity.Plant intensity requires the number of the plants be limited in order to avoid vain growth of leaf blades caused by dense planting,which will destroy the harmony between leaf blades and flower arrows and mar the beauty.Cymbidium hybridium whose budding period is in November should be carefully nursed and moderately warmed according to the time for market sales.Hormone regulation should be performed according to the growth characteristics of flower arrows rather than its growing stages.Meanwhile,classified regulation should be carried out to cymbidium hybridium with different numbers of buds and those unpopular and defective plants should be eliminated in time.The above agronomic characters should be taken into account in the experimental study and production of flower cultivation.One point worth mentioning is that emphasis should differ according to different periods,that is, take appropriate measures and improve cultivation techniques, harmonize the relationship between the main agronomic characters.That can facilitate the achievement of the purpose of producing cymbidium hybridium with high quality.