Studies On The Growth And Physiological And Biochemical Characters Of Camptotheca Acuminate From Different Provenances Under Flooding Stress

Camptotheca acuminate, a fast-growing tree in warm places, is high economic, medicinal and ornamental values. There is the wetland and coastal interval account great proportion of the land area in our country. To study flooding-stress of sapium is essential to establish various Camptotheca plantations.The growth and physiological characters of two-month seedlings of Camptotheca, respectively belong to eight different provenances, were reported in this paper. The results were as follows:(1) Under flooding stress, there was no significant difference on survival rates of eight kinds of Camptotheca.The survival rates of Nanlin and Huangshan provenance was over 80%,but Chengbu and Chuxiong provenance was below 35%.The average was 55%. The high growth from most of provenances was stopped after one week. But there was little difference between treatments in stem base growth. Even the treatment was faster than the contrast in the early period. The root moisture content of Chengbu and Chuxiong provenance was higher than the contrast.(2) The chlorophyll content and net photosynthetic rate of the treatment were below ones of the control, but there was no obvious difference between treatment and control in the chlorophyll content.The different provenance's net photosynthetic rate dropping was relevant to the decline of the chlorophyll content.(3) Under flooding stress, there were significant influences on membrane permeability, the activity of protective enzyme, active oxygen and MDA accumulation. The SOD activity of all provenances firstly increased and then decreased. The POD activity of all provenances declined. The MDA content of all provenances firstly increased and then decreased except Zhejiang. The H2O2 content of all provenances increased gradually except Hunan.(4) The proline content continually rose except the Chengbu and Chuxiong provenance, which firstly rised then declined? The protein contents of Zhejiang, Jiangsu and Anhui provenance were basically the same as the control. Others declined.(5) By using principle component analysis and subordinative function to make comprehensive evaluation to different provenances, the sequence of resistance to flooding stress was ranked from high to blow as follows:Longquan in Zhejiang, Nanlin, Huangshan in Anhui, Honghezhou in Yunnan, Taishun in Zhejiang, Chengbu 8th in Hunan, Chengbu 7th in Hunan and Chuxiong in Yunnan.