根区低温对嫁接的黄瓜幼苗根系生长和^(15)N吸收分配的影响  

Effect of low root-zone temperature on growth and ^(15)N uptake and distribution characteristics in grafted cucumber seedling root

作　　者：孙世君[1] 付崇毅[2] 宋阳[1] 乌日力格 薛艳君[1] 崔世茂[1] 

机构地区：[1]内蒙古农业大学农学院,呼和浩特010019 [2]内蒙古农牧业科学院,呼和浩特010031

出　　处：《植物生理学报》2017年第8期1545-1552,共8页Plant Physiology Journal

基　　金：国家自然科学基金(31060269);内蒙古自治区科技计划项目(20110710);教育部博士点基金(201015110005);内蒙古研究生科研创新重点项目(B20151012904Z)~~

摘　　要：以黑籽南瓜(Cucurbita ficifolia)嫁接苗("黑籽")、白籽南瓜(C.maxima×C.moschata)嫁接苗("白籽")和‘津优35号’("自根")为试材,研究了常温(18~20°C)、亚适温(13~15°C)、低温(8~10°C)三种根区温度对黄瓜(Cucumis sativus)幼苗根系生长和^(15)N吸收和分配特性的影响。结果表明:亚适温和低温处理显著抑制了黄瓜幼苗根系长度、表面积、体积、根尖数以及分叉数,造成黄瓜幼苗根系丙二醛(MDA)含量增加,超氧化物歧化酶(SOD)和过氧化物酶(POD)活性降低。随着根区温度降低,黄瓜幼苗根系氮肥吸收比例(Ndff)升高,茎和叶片Ndff降低,^(15)N分配在根和茎增多,叶片减少,^(15)N利用率逐渐降低。亚适温和低温处理下,"黑籽"的根系形态特征、抗氧化酶活性、^(15)N吸收分配和利用均优于"白籽"和"自根","黑籽"南瓜嫁接苗生长的黄瓜幼苗根区对低温的适应能力最强,"自根"受到的根区低温胁迫伤害最大。With black seed pumpkin（Cucurbita ficifolia） grafting, white seed pumpkin（C. maxima × C. moschata） grafting and ‘Jinyou No. 35＇ cucumbers（Cucumbis sativus） as test materials, and the self-developed ground temperature device to control cucumber seedling growth period（22：00–8：00 ＋ 1 d） to normal（18–20℃, optimal（13–15℃ and low（8–10℃ temperatures, the effects of different root-zone temperatures on cucumber seedling root growth and ^15N uptake and distribution were investigated. The results show that the optimal and low temperature treatments significantly inhibited cucumber root length, surface area, volume and numbers of roots and branches, increased the content of malondialdehyde（MDA）, reduced the activities of superoxide dismutase（SOD） and peroxidase（POD）. With the increase of root-zone temperature, the value of nitrogen derived from fertilizer（Ndff） rose in roots, and decreased in stems and leaves; ^15N distribution rose in roots and stems, and reduced in leaves gradually; and ^（15）N utilization gradually decreased. Under optimal and low temperature treatments, the root morphology, antioxidant enzyme activities and ^（15）N uptake and utilization of black seed pumpkin grafting cucumber were superior to white seed pumpkin grafting and ‘Jinyou No. 35＇ cucumbers. Black seed pumpkin grafting cucumber had the strongest adaptability to low root-zone temperature, and ‘Jinyou No. 35＇ was damaged most seriously by low temperature.

关 键 词：黄瓜幼苗 根区低温 根系生长 ^15N吸收分配 

分 类 号：S642.2[农业科学—蔬菜学]