摘要
We have reported that the roots of figleaf gourd(Cucurbita ficifolia,as rootstock) could improve the resistance of cucum-ber seedlings(Cucumis sativus L.cv.Jinyan 4,as scion) to 6 h stress at low temperature and low irradiance [1].In this experiment,the relationship between the mineral elements uptake and photosynthetic activity of photosystems in figleaf gourd and cucumber seedlings were to be studied during lowtemperature(8 C) stress under lowirradiance(100 μmol m-2 s-1 PFD) for 5 days.Compared with control seedlings,the maximal photochemical efficiency of PS2(Fv/Fm) and the oxidizable P700(P700+) of both figleaf gourd and cucumber seedlings decreased,and both Fv/Fm and P700+ were lower in cucumber leaves than in figleaf gourd seedlings at the end of the stress.Superoxide dismutase(SOD) activity was higher in both leaves and roots of figleaf gourd than in leaves and roots of cucumber at both room temperature and low temperature.However,the product rate of O 2 was lower in figleaf gourd leaves than in cucumber leaves.Upon ex-posure to the stress,the malondialdehyde(MDA) content increased markedly in leaves and roots of figleaf gourd and cucumber seedlings,and it grewfaster in cucumber seedlings than that in figleaf gourd seedlings.Under adaptive conditions,some mineral elements(Such as Cu,Zn,Mn and Mg) have different contents in leaves and roots between figleaf gourd seedlings and cucumber seedlings.However,at the end of the stress these elements were accumulated apparently in both leaves and roots of figleaf gourd accompanied by no obvious change in cucumber seedlings.
We have reported that the roots of figleaf gourd（Cucurbita ficifolia,as rootstock） could improve the resistance of cucumber seedlings（Cucumis sativus L.cv.Jinyan 4,as scion） to 6 h stress at low temperature and low irradiance [1].In this experiment,the relationship between the mineral elements uptake and photosynthetic activity of photosystems in figleaf gourd and cucumber seedlings were to be studied during lowtemperature（8 C） stress under lowirradiance（100 μmol m-2 s-1 PFD） for 5 days.Compared with control seedlings,the maximal photochemical efficiency of PS2（Fv/Fm） and the oxidizable P700（P700＋） of both figleaf gourd and cucumber seedlings decreased,and both Fv/Fm and P700＋ were lower in cucumber leaves than in figleaf gourd seedlings at the end of the stress.Superoxide dismutase（SOD） activity was higher in both leaves and roots of figleaf gourd than in leaves and roots of cucumber at both room temperature and low temperature.However,the product rate of O 2 was lower in figleaf gourd leaves than in cucumber leaves.Upon exposure to the stress,the malondialdehyde（MDA） content increased markedly in leaves and roots of figleaf gourd and cucumber seedlings,and it grewfaster in cucumber seedlings than that in figleaf gourd seedlings.Under adaptive conditions,some mineral elements（Such as Cu,Zn,Mn and Mg） have different contents in leaves and roots between figleaf gourd seedlings and cucumber seedlings.However,at the end of the stress these elements were accumulated apparently in both leaves and roots of figleaf gourd accompanied by no obvious change in cucumber seedlings.
基金
This research was supported by the Natural Science Foun-dation of China(30571126,30671242)
the Scientific Research Encouragement Foundation for Outstanding Young and Middleaged Scientists of Shandong Province,China(2005BS06003)
关键词
黄瓜
葫芦
低温
矿物元素摄取
cucumber, figleaf gourd, low temperature stress, photoinhibition, mineral elements uptake
