水澇脅迫下海濱錦葵幼苗根尖細胞內Ca2+分布與變化1)

周建　　　　　　欽佩

(河南科技學院，新鄉，453003)　　　　　(南京大學)

?

水澇脅迫下海濱錦葵幼苗根尖細胞內Ca2+分布與變化1)

周建欽佩

(河南科技學院，新鄉，453003)(南京大學)

摘要采用醋酸雙氧鈾染色與透射電鏡技術，以海濱錦葵為試驗材料，連續觀測水澇脅迫下及澇后恢復期間海濱錦葵根尖細胞內Ca(2+)的分布與變化特性。結果顯示：隨著水澇時間延長，海濱錦葵根尖細胞間隙與細胞核、液泡中鈣離子沉積密度逐步降低，質體外膜上存在Ca(2+)分布，但低于對照組，而Ca(2+)向細胞質移動，在局部區域聚集，導致細胞質鈣離子增加。水澇去除20 d后，細胞壁中出現鈣離子沉積，細胞間隙、質體外膜上與液泡中所分布鈣離子增加，細胞質所聚集的Ca(2+)逐步分散，基本不存在Ca(2+)沉積。研究認為，水澇脅迫下，海濱錦葵根尖細胞內Ca(2+)濃度迅速上升；澇后恢復期間，Ca(2+)濃度逐漸下降，起著外界信號傳遞的作用。

關鍵詞水澇脅迫；海濱錦葵；根尖細胞；Ca(2+)；離子分布

分類號Q945.78

Distribution and Variation of Ca2+in Root Apical Cells ofKosteletzkyavirginica(L.) Seedlings under Waterlogging

Zhou Jian

(Henan Institute of Science and Technology, Xinxiang 453003, P. R. China); Qin Pei(Nanjing University)//Journal of Northeast Forestry University，2016,44(3)：61-67.

WithKosteletzkyavirginica(L.), we observed its distribution and variation of Ca2+in root apical cells continuously by transmission electron microscope combined with uranyl acetate staining method in and after waterlogging stress. During waterlogging, Ca2+of root apical cells mainly distributed within intercellular spaces, nuclei and vacuoles, but the density of Ca2+reduced gradually. Additionally, there were calcium ions located on outer membranes of plastids, but its density was lower than that in control within this stress. However, Ca2+showed a trend to move into cytoplasm, and accumulated to in some areas. On the 20 th day after drainage of waterlogging, the amassed calcium ions released, and almost no Ca2+distributed in cytoplasm. However, with the release of cytoplasm Ca2+, the densities of calcium ions were increased in intercellular space, vacuoles and outer membrane of plastid, a great deal of Ca2+located with cell walls in recovery period. After 20 days of recovery, the distribution of Ca2+in waterlogged plants was similar to that in control ones. The density of Ca2+in root apical cell was increased quickly in waterlogging and subsequently decreased in restoration, and Ca2+not only affected cell function, but also acted as a means to transmit outside information inK.virginicaplants.

KeywordsWaterlogging stress; Kosteletzkya virginica (L.); Root apical cell; Ca(2+); Ion distribution

植物在生長發育過程中經常遭受一系列的環境脅迫，包括生物脅迫與非生物脅迫。在相關植物脅迫研究中，其信號轉導途徑一直是人們關注的焦點。生物脅迫主要包括有細菌、真菌、病毒及由此產生的病害。非生物脅迫則主要包括干旱、水澇、鹽堿、高溫、低溫凍害等[1]。植物為了適應各種環境脅迫，最大限度地減少逆境對自身的傷害，在長期的進化過程中，形成了一系列復雜的逆境信號傳遞機制。

鈣離子是植物重要的第二信使，保持鈣的恒穩態是細胞正常生長發育的前提，由此而誘發以后一系列信號轉導的下游事態[2]。……