腐殖酸鈉對鎘脅迫下冬小麥種子萌發(fā)及根系生長的影響

孫梟瓊 陳永亮 孫慎麗 陳玉倩 朱笛 周曉燕 高夢杰 韓慶典

摘要 [目的] 研究腐殖酸鈉（HA-Na）對鎘脅迫下冬小麥種子萌發(fā)及根系生長的影響。[方法]以魯麥22號為試驗(yàn)材料，研究不同濃度Cd2+溶液處理對冬小麥種子萌發(fā)和根系生長的影響，以及不同濃度HA-Na溶液對Cd2+脅迫下冬小麥種子萌發(fā)和根系生長的影響。[結(jié)果] Cd2+脅迫使冬小麥種子萌發(fā)和根系生長均受到抑制，發(fā)芽率、發(fā)芽指數(shù)、活力指數(shù)、幼苗根長及芽長均降低。低濃度的HA-Na提高了Cd2+脅迫下冬小麥種子發(fā)芽勢、發(fā)芽率、發(fā)芽指數(shù)、活力指數(shù)以及幼苗根長、芽長，部分緩解了Cd2+脅迫對冬小麥種子萌發(fā)和幼苗生長的抑制作用。其中以50 μmol/L HA-Na溶液處理的緩解效果最好，但隨著HA-Na濃度的增大，其對Cd2+脅迫的緩解效應(yīng)逐漸減弱，當(dāng)HA-Na濃度達(dá)200 μmol/L時(shí)，會(huì)明顯加劇Cd2+脅迫的毒害作用。[結(jié)論]該研究為被重金屬污染的農(nóng)田土壤治理和改良提供了理論依據(jù)。

關(guān)鍵詞 冬小麥；腐殖酸鈉；鎘脅迫；萌發(fā)；生長

中圖分類號 S145.4；S512.1+1 文獻(xiàn)標(biāo)識(shí)碼 A 文章編號 0517-6611（2017）13-0034-02

Effect of Sodium Humate on Winter Wheat Seed Germination and Root Growth under Cadmium Stress

SUN Xiao-qiong， CHEN Yong-liang， SUN Shen-li，ZHOU Xiao-yan* et al

（College of Life Science，Linyi University，Linyi，Shandong 276005）

Abstract [Objective] To study the effect of sodium humate（HA-Na） on winter wheat seed germination and root growth under cadmium stress. [Method] With Lumai 22 as material，we analyzed effects of different concentrations of Cd2+ solution on winter wheat seed germination and root growth，then explored effects of different concentrations of HA-Na solution on seed germination and root growth under cadmium stress. [Result] Winter wheat seed germination and root growth were inhibited by Cd2+ stress，germination index，vigor index，root length and bud length were decreased. Low concentrations of HA-Na improved winter wheat seed germination rate， germination index and vigor index，also improved root length，bud length under Cd2+ stress，and partial relieved seed germination and seedling growth under Cd2+ stress. The ameliorative effect of 50 μmol/L HA-Na was best among them. But with the increasing of concentration of HA-Na， the ameliorative effect of Cd2+ stress weakened gradually.It would significantly increase the toxic effects of cadmium stress while HA-Na concentration reached 200 μmol/L.[Conclusion] The study provides the theory basis for farmland soil management and improvement that has been polluted with heavy metals.

Key words Winter wheat；Sodium humate；Cadmium stress；Germination；Growth

礦產(chǎn)資源的大量開發(fā)和使用，導(dǎo)致土壤重金屬污染越來越嚴(yán)重。研究表明，植物中的重金屬累積到一定濃度，就會(huì)抑制其生長發(fā)育[1-3]。重金屬鎘（Cd）是重要的金屬污染物之一，其化學(xué)行為和生態(tài)效應(yīng)相對復(fù)雜，毒性很強(qiáng)，且容易被植物吸收。我國農(nóng)田的鎘污染面積已達(dá)1.4×104 hm2 [4]，且面積正迅速增加，亟需一些經(jīng)濟(jì)有效、切實(shí)可行的方法來解決。

冬小麥?zhǔn)鞘澜缟现饕募Z食作物，也是山東半島地區(qū)主要的種植作物。目前關(guān)于重金屬對冬小麥生長發(fā)育的影響及危害機(jī)制已有部分報(bào)道[5-8]?！?br>