关键词: 青脆李, 海拔高度, 光合特性, 生理辐射, 果实品质

Abstract: Different Qingcui plum habitats were selected from 3 altitudinal gradients in northern part of Hengduan mountains to study physiological radiation,photosynthetic properties and fruit qualities of Qingcui plum,especially analyze light response of photosynthesis (Pn-PPFD) response curve and the correlation between fruit qualities and physiological radiation and photosynthetic parameters of Qingcui plum.The results showed that the physiological radiation intensity and ratio of short wave light increased with altitude,apparent quantum yield (α) was highest,reaching 0.091,while light compensation point (LCP) was lowest at low altitude,which indicated Qingcui plum leaves had a good ability to utilize the low light.However,the light saturated point (LSP) was significantly higher at high altitude than at low altitude,which showed Qingcui plum leaves at high altitude had a good ability to utilize the strong light.Furthermore,low light was more at low altitude while strong light more at high altitude.Thus,they indicated that Qingcui plum was capable of adapting to low or strong light.In fact,the maximum photosynthetic rate (P_max),dark respiration rate (Rd),LCP and LSP were the highest at 1 786 m,P_max reached 21.12 μmol/ (m²·s).Chla/Chlb was significantly and positively correlated with apparent quantum yield,and Car significantly and positively with LSP.The strong intensity of physiological radiation and short wave light helped to accumulate TSS,Vc and sugar content,but was detrimental to the accumulation of organic acid content and fruit mass.

Key words: Qingcui plum, altitude, photosynthetic properties, physiological radiation, fruit quality