【摘要】：本試驗(yàn)研究了 Cd對煙草種子萌發(fā)、幼苗生長發(fā)育的影響,采用盆栽試驗(yàn)研究了不同生物炭、豆餅用量對煙草中重金屬Cd的鈍化作用以及在整個(gè)生長發(fā)育過程中對煙株的影響。旨在為我省控制煙草中的Cd提供理論基礎(chǔ)。主要研究結(jié)果如下:(1)Cd污染對煙草種子具有毒害作用。本試驗(yàn)表明,隨著Cd濃度的增加,煙草種子發(fā)芽勢、發(fā)芽率、發(fā)芽指數(shù)、活力指數(shù)、苗高,均受到了一定程度的抑制。當(dāng)Cd濃度為10 mg/L時(shí),幼芽毒害死亡率超過了 50%。(2)在Cd脅迫下,煙草幼苗生長受到一定程度的抑制,且隨Cd濃度的不斷增大,抑制程度也不斷增加。葉綠素含量顯著降低,幼苗生長長勢越來越差,根冠比逐漸變小,抑制了煙苗的健康生長。(3)在Cd脅迫下,幼苗體內(nèi)抗氧化酶系統(tǒng)被破壞,多種酶活性不協(xié)調(diào),生理過程紊亂,最終導(dǎo)致煙苗受害。CAT活性、SOD活性、可溶性糖含量表現(xiàn)為先增加后降低的趨勢,POD活性、MDA含量、Pro含量、Cd含量均隨Cd濃度的增加而增加。(4)在Cd脅迫下,煙株生長發(fā)育受到抑制,在不同鈍化劑處理下,生長在不同濃度Cd污染土壤中的煙株在株高、葉片數(shù)、最大葉長、最大葉寬、莖圍、干物質(zhì)積累、根冠比有不同程度的增加,能夠減輕Cd脅迫對煙株的抑制作用,促進(jìn)煙株的生長發(fā)育。(5)不同鈍化劑能夠緩解Cd脅迫對煙株體內(nèi)抗氧化酶系統(tǒng)的破壞,不同程度的增加葉綠素含量、CAT活性,降低POD活性、MDA含量、Pro含量;當(dāng)Cd≤5mg/kg時(shí),SOD活性降低,當(dāng)Cd濃度為10mg/kg時(shí),SOD活性升高;當(dāng)Cd≤2mg/kg時(shí),可溶性糖含量降低,當(dāng)Cd≥5mg/kg時(shí),可溶性糖含量升高。(6)煙葉中的Cd含量隨Cd濃度的升高而升高。在整個(gè)生長發(fā)育期間,Cd含量的變化趨勢為先降低后增高。當(dāng)在土壤中施以鈍化劑時(shí),能夠不同程度的降低煙葉中各部位的Cd含量,說明鈍化劑對煙草中的Cd具有消減作用。(7)Cd脅迫下,煙葉化學(xué)成分趨于不協(xié)調(diào),不利于優(yōu)質(zhì)煙葉的形成,當(dāng)在土壤中施以鈍化劑時(shí),能夠降低總氮含量、蛋白質(zhì)含量、總糖含量、還原糖含量,增加煙堿含量、淀粉含量,使得施木克值、糖堿比、氮堿比降低,鉀氯比增加。(8)煙株中的Cd含量分布為根莖上部葉中部葉下部葉。當(dāng)土壤中施以鈍化劑時(shí),各部位煙葉中的Cd含量均有不同程度的降低,減少了煙株對Cd的吸收。(9)兩種鈍化劑及不同比例對煙葉吸收重金屬影響不盡相同,其中0.5%生物炭綜合表現(xiàn)好于1.0%生物炭,0.5%豆餅綜合表現(xiàn)好于1.0%豆餅。
[Abstract]:The effects of CD on the germination of tobacco seeds and the growth and development of tobacco seedlings were studied. Pot experiments were conducted to study the effects of different amounts of biochar and soybean cake on the passivation of CD in tobacco and the effects of CD on tobacco plants during the whole process of growth and development. The aim is to provide a theoretical basis for the control of CD in tobacco in our province. The main results are as follows: (1) CD pollution has toxic effect on tobacco seeds. The results showed that with the increase of CD concentration, the germination potential, germination rate, germination index, vigor index and seedling height of tobacco seeds were inhibited to some extent. When CD concentration was 10 mg / L, the death rate of shoot toxicity exceeded 50%. (2) under CD stress, the growth of tobacco seedlings was inhibited to a certain extent, and with the increasing of CD concentration, the inhibition degree also increased. Chlorophyll content decreased significantly, seedling growth became worse and worse, root to shoot ratio gradually decreased, which inhibited the healthy growth of tobacco seedlings. (3) under CD stress, the antioxidant enzyme system was destroyed, the activities of many enzymes were not coordinated, and the physiological process was disturbed. The content of soluble sugar increased firstly and then decreased. The content of MDA and Pro increased with the increase of CD concentration. (4) under CD stress, the growth and development of tobacco plants were inhibited. Under different passivant treatments, the plant height, number of leaves, maximum leaf length, maximum leaf width, stem circumference, dry matter accumulation and root-shoot ratio increased in different concentrations of CD contaminated soil. (5) different passivating agents can alleviate the damage of antioxidant enzyme system and increase the activity of cat in chlorophyll content in different degree, which can reduce the inhibition of CD stress on tobacco plants, promote the growth and development of tobacco plants, and promote the growth and development of tobacco plants. The activity of SOD decreased when CD 鈮，

本文編號：2134047