Study On Different Forms' Calcium And The Activities Of Several Enzyme In Cerasus Humilis Various Organs During Spring And Autumn

Potted and wild Cerasus humilis were used as materials in the experiment. The content of total calcium and different forms'calcium,the activities of Ca²⁺-ATPase and H⁺-ATPase in different tissues and organs of Cerasus humilis,the absorptive activities and absorptive area of root were mensurated.And then the seach has analyzed the dynamic variety of several physiological indexes and the their correlation between each other in different tissues and organs of Cerasus humilis under different cultivation methods at spring and autumn,In addition the characteristics of the roots calcium uptake was explored. The main results are as follows:In the fall before November 4 all tissues of Cerasus humilis experienced the state of absorption and accumulation of calcium. And the peak concentration was formed at this time. Then in addition to the calcium content of branches'phloem increasing , the total calcium contents of the remaining parts were declined. Correlation analysis showed that the contents of calcium pectate, calcium phosphate and residual calcium in most tissues had a significant positive correlation with the total calcium content. Simultaneity the contents of alcohol-soluble calcium, water-soluble calcium were negatively with the total calcium contents related to some different degrees.At spring the calcium content and the forms in different tissues of Cerasus humilis showed different rules. Total calcium content in each tissue was higher in the early growing season, lower in the middle season; radicula and medium-coarse root appeared lowest total calcium content at the March 28.Total calcium contents of tap root phloem and ground tissues were lowest in April 7,latter total calcium contents were restored, then radicula and medium-coarse root emerged a peak. From germination to flowering period, the main body calcium of prunus distributed mainly in the phloem. During this period total calcium content of various root parts showed a positive correlation. The total calcium content of taproot xylem was negatively correlated with that of branches and buds respectively.The total calcium content of phloem and xylem of branches, buds, flower organs and shoots showed significant positive correlation. At spring the total calcium contents of the phloems were significantly higher than those of the xylems, and the contents of alcohol-soluble calcium, soluble calcium and calcium pectin in the phloems were higher than those of the xylems.Active calcium (soluble calcium) was the main form of transportation and absorption.The main calcium form of the various phloems in Cerasus humilis was oxalate-calcium.But the floral organ mainly remained in form of calcium pectate.In the fall, the Ca²⁺-ATPase activity of medium coarse root'xylem appeared a lowest valley in the Oct.20.The enzyme activity of the remaining part remained stable before the Oct.20,Then the enzyme activity of branch was slightly decreased,while the enzyme activity of other tissues and organs promoted significantly.The H⁺-ATPase activity of Cerasus humilis'radicula was stable during the growth stage of autumn, The enzyme activity of the remaining parts reached the lowest until Oct.20, Then the activity change of them was no significant.The Cam content of leaves and branch'phloem maintained a sustained decline during sampling period of autumn, The variation of CaM content of medium coarse root'xylem increased first,then decreased,and increased at last,while the CaM content of the remaining tissues and organs were basic stable.At spring, the Ca²⁺-ATPase activity of radicula and various phloem of root and the H⁺-ATPase activity of coase root and medium coarse root'phloem remained stable during sampling period,while the variation of the two enzymes activity of the remaining organs and tissues showed the trend of U shape. The CaM content of cultivation,the phloem of branch,the phloem of medium coarse root and bud,flower/shoot maintained a sustained increase during sampling period of spring, Although the CaM content of the remaining parts appeared slight fluctuation during the period,but there is not much different between the final content and the initial content.In the range of Ca²⁺ concentration provided(0⁵mmol/L), The rates of Ca²⁺ absorption of excised radicula exhibit two different curves.Under condition of lower Ca²⁺ concentration range(0⁰.5mmol/L), The rate of Ca²⁺ absorption fit into the Michaelis-Menten model,while under higher Ca²⁺ concentration range (0.5⁵mmol/L), The rate of Ca²⁺ absorption rised linearly with the increasing of Ca²⁺ concentration.