Study On Phosphorus Nutritional Physiology Of Cymbidium Hybridum

Cymbidium hybridum is an important commodity potted in the intrenational flower market. Currently, our country has little research on nutrition physiology and fertilization technique of Cymbidium.This paper studied the potted fertilization through regular sampling tests,studied the impact on growth and blossom of Cymbidium.'Marilyn Monroe'and Cymbidium.Walu'Idol'under different phosphorus application, and the impact on the dry weight of organs, the percentage of nutrients and the absorption of nutrients. Studied the utilization ratio of phosphorus on Cymbidium.'Marilyn Monroe'one-year plant and so on .The main result are as follows:1. In the vegetative growth phase , Cymbidium.'Marilyn Monroe'and Cymbidium.Walu'Idol'annual seedlings little demand for phosphorus, 4.5mg per month on capacity can be phosphorus, excessive use catalytic role not significant.2. Increasing the P application rate in some degree can promote the stage of flower bud differentiation and flowering, but not the more phosphate fertilizer application, the better the quality of flowering. It is benifit for florescence the number of flower, flower arrow , length of flower arrow, diameter of flower and ratio of flower of Cymbidium.'Marilyn Monroe'under 27.0～54.0mg each plant per month. It had a catalytic role on the Cymbidium.Walu'Idol'under 4.5mg each plant per month.3. To organs of Cymbidium.'Marilyn Monroe'annual seedlings, the demand quantity of total nitrogen, total phosphorus and potassium is small during vegetative growth stage .The utilization of phosphorus is relatively higher under 4.5 mg per month each phosphate application rate,10.93 percent, close to the utilization of phosphorus that conventional values,at this time the total annual P absoption of Cymbidium.'Marilyn Monroe'annual seedlings is 57.1mg each. Nitrogen, potash fertilizer utilization is up 61.77 percent and 71.30 percent.4. Through comparison and analysis of dry weight, organs soluble sugar, C/N, nutrient content of Cymbidium.'Marilyn Monroe'and Cymbidium.Walu'Idol'annual seedlings after two years cultivation which were growm in this test and the same age plants of Gu'an,. The reasons in nutrient accumulation that Cymbidium in the test is not flowering normally can be concluded preliminarily as follows:(1) The main reason may be too high summer temperatures in the greenhouse, after two consecutive summer heat stress, matrix produce fungi,the organs can not absorb nutrition normally, low nutrient content does not meet the necessary conditions of flower bud differentiation .(2) Through the analysis of the water of two places , it can be found that the test tap water for sodium content of 33.25 mg ? L-1, Gu'an sodium content is 21.98 mg ? L-1, the former significantly higher than the latter, the inference may be sodium ion poisoning caused Cymbidium plants can not absorb nutrients normally, can not meet the necessary conditions for flower bud differentiation.