| As one of the traditionally famous flowers in China, the natural florescence of Tree Peony was about 7 days. Since the florescence related to both its ornamental value and the economic benefit of producing area, we took potted Tree Peony as material, by contrast with that grown under natural condition, cultivated in greenhouse treated with different Calcium concentration and fertilizing period. The senescence process and their difference were studied by morphological, physiological, biochemical, enzymological and ELISA methods. Effects of different Ca concentration and fertilizing period treatments were showed by the change of the physiological and biochemical indexes, such as soluble protein content, amino acid content, Membrane permeability, CaM content, malondialdehyde (MDA) content, vigor of superoxide dismutase (SOD), active oxygen (02) production rate, ethylene releasing rate, abscisic acid (ABA) and cytabolic (CTK) content as well. Their mutual relationship was also considered. The results were useful to realize the senescence process and relevant reason of Tree peony, discuss Calcic influence towards Tree Peony petals during senescence, what's more, expect to provide academic basis for extending its florescence and economic benefit both in greenhouse and natural condition.1 under natural condition, through morphological analysis, physiological and biochemical indexes, the senescence process could be divided into three periods: initial period, blooming period and fading period over whole florescence. At initial period, all petals did not stretch, but the color was very fresh. During blooming period, all petals stretched and flowers had maximal diameter. At the third period, color was fading. Petals lost water and their edge became curls. Petals were not straight but droopy or regatta. At the end of fading period, surface layer petals began to shed; therefore, the flower basically lost its ornamental value.2 Soluble protein content for petals increased at prophase, then fast decreased at anaphase; Membrane permeability, malondialdehyde (MDA) content and active oxygen (O2") production rate gradually enhanced at prophase, and the rapidly changing period is about 5d, whereas, the activity of superoxide dismutase(SOD) was opposite; After anthesis , ethylene release rate of petals fell quickly, then gradually increased to tiptop in 5d. At the same time the changes of leaves was ascending. During petals senescence abscisic acid (ABA) content continued to ascending, but cytabolic (CTK) content decreased. All above changes were more obvious in petals than in leaves, which was similar to morphological observation; correlitivity of senescence indexes showed soluble protein content and Membrane permeability evidently correlated to MDA content, SOD activity and O2- production. Therefore, we can refer to soluble protein content and Membrane permeability as indexes in studying tree peony's senescence.3 With the accretion of Ca concentration, Tree Peony's florescence could extent 1-2d(CK 17d, Ca1 18d, Ca2 18d, Ca3 19d, Ca4 19d). Under high Ca part of materials blossomed out lately, which oppositely leaded to longer colony florescence. But during delayed period, buds had to miss the optimal period toabsorb nutrient, then flowering ratio fell down(CK 80.3%, Ca1 83.9%, Ca2 88.1 %, Ca3 89.5%, Ca4 78.2%). Therefore, when lack of Ca, fertilizing exterior Ca can put off its florescence. But the reason why excessive Ca can make flowering ratio down should be researched more.4 some physiological and biological indexes with different Ca concentration during senescence were also researched. The results revealed that: High Ca content could suspend the decompounding time and speed of soluble protein, reduce MDA content and O2- production rate, increase SOD vigor, decrease ABA content and ethylene releasing rate, and increase photosynthesis of leave, which could reduce membrane peroxidization of petals, then putting off its senescence process.5 different fertilizing period showed different impact, on sen...
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