不同重金属对‘黄花’梨花粉萌发及花粉管生长的影响  

Effects of different types of heavy metals on pollen germination and tube growth of the 'Huanghua' pear

作　　者：陈至婷 徐凯 史梦琪 高永彬 

机构地区：[1]浙江农林大学农业与食品科学学院.浙江省农产品品质改良技术研究重点实验室,浙江临安311300

出　　处：《果树学报》2017年第10期1266-1273,共8页Journal of Fruit Science

基　　金：浙江省自然科学基金(LQ15C150003);浙江农林大学科研发展基金(2014FR067)

摘　　要：【目的】检测几种常见重金属对梨花粉萌发及花粉管生长的作用特点。【方法】采用液体培养法研究镍(Ni)、镉(Cd)、铜(Cu)、铅(Pb)和锌(Zn)等5种常见重金属对‘黄花’梨花粉萌发以及花粉管长度的影响,以电子显微镜检测重金属处理后花粉管尖端形态变化,并用NBT结合荧光探针标记分析花粉管尖端ROS分布。【结果】随着Ni^(2+)、Cd^(2+)、Cu^(2+)、Pb^(2+)和Zn^(2+)浓度增加,花粉萌发率越低且对花粉管伸长的抑制作用越明显。在以上5种重金属中,Pb对梨花粉萌发及花粉管伸长的影响最小,而Cu的影响最大。经过重金属处理后,花粉管尖端会出现不同程度的肿胀现象,并且维持花粉管极性生长的尖端活性氧(reactive oxygen species,ROS)浓度梯度受到破坏。Cu处理后花粉管尖端肿胀率最高,且显著高于其他4种重金属处理。【结论】以上5种重金属对‘黄花’梨花粉萌发和花粉管伸长的抑制作用呈现浓度依赖性,并表现出Pb<Ni<Cd<Zn<Cu的趋势。经重金属处理后,花粉管尖端发生肿胀,尖端ROS浓度梯度被破坏。不同处理下花粉管尖端肿胀率与其花粉萌发及花粉管伸长所受抑制程度相一致。[Objective] Heavy metal pollution has become one of the serious environment problems along with social and economy development. These excessive heavy metals often exhibit negative effects on plant cells or organ growth, such as pollen germination and tube growth. During the pear reproductive period, pollen grains are exposed in air and are prone to pollution by some heavy metals. However, the effects of heavy metals on pear pollen germination and tube growth remain unknown. This present study evaluates the properties of Ni, Cd, Pb, Cu and Zn treatments on pear pollen germination and tube growth, respectively. [Methods] Pollen grains from the cultivar ＇Huanghua＇ （Pyrus pyrifolia） are collected from the Zhejiang A ＆ F University Fruit Experimental Yard, preserved by drying in air at ambient temperature （25 ℃） for 12 h, and then stored in silica gel at -20℃. Mature pear pollen grains were cultured in a culture medium in the dark at 25 ℃ for 3 h with a constant temperature shaker （100 r· min-1）. The culture medium con- tained 0.03% CaCl2,0.01% H3BO3, 10% sucrose, 15% polyethylene glycol 4 000 and 30 mmol·L-1 MES, pH 6.0 （adjusted with Trizma base）. Ni〉, Cd2＋, Cu〉, Pb2＋ and Zn2＋ were added to the culture medium before the pollen grains culture. The final treatment concentrations of Ni2＋, Cd〉, Cu〉, pb2＋or Zn〉 were 25, 50 and 100 μmol· L-1, respectively. When the germinated tube length was more than the diameter of the pollen grain, this pollen grain was considered as pollen germination. The germination rate is equal to the number of germinated pollen/total pollen number; 100 pollen grains （or tubes） were counted in each repeat. Pollen tube length and shape changes of the pear pollen tube tip were captured and analyzed by a microscope with a CCD camera and Image-Pro plus6.0 software, respectively. Data were analyzed with both Excel and SPSS 22.0 software. The tip-localized reactive oxygen species （ROS） were stained by Nitroblue tetrazolium （NBT; 1 g. L-1） a

关 键 词：梨 重金属 花粉萌发 花粉管生长 

分 类 号：S661.2[农业科学—果树学]