【作者】 母波； 韩善华；

【Author】 Mu Bo Han Shanhua Cell Biology Laboratory, Sichuan Normal University, Chengdu, 610066

【机构】 四川师范大学细胞生物学研究室；

【摘要】 烟草是烟草工业的重要原料,其生长的好坏直接与氮的供应有关,为此我们对它进行了人工诱瘤研究。以全国广泛推广的良种烟草(Nicotiana tobacum L．)K326为材料,先将种子培养成无菌苗, 再将其叶片切成小块并培养成再生小植株。然后在液体培养基中用2,4-D(0．3mg／L)诱导和豇豆根瘤菌512(5×108个／L)侵染,使其在根部大量结瘤。为了探索根瘤化对烟草中主要保护酶的影响,在过去工作的基础上,我们用分光光度法测定了根瘤化烟草生长不同时期的根、茎和叶中的SOD活性。测定表明,在1-5周内,根瘤化对烟草的SOD活性有不同程度的影响,这种影响随器官不同而不同。在根、茎和叶中,以叶片中的SOD活性最高,茎次之,根最低。它们SOD最高活性出现的时期也不一样,根和叶是在第二周,而茎则出现在第三周。不仅如此,而且根瘤化对烟草植株中SOD活性的影响也与时间有关,在根瘤化早期(1-2周),烟草中的SOD活性是逐渐升高,当其超过2周后则开始下降,与此同时,根瘤化早期的烟草生长正常,无明显变化,但开始大量结瘤后,它们的生长却受到不同程度的抑制,出现衰老现象,并随时间的增加而逐渐加重,这种现象的出现可能与根瘤化烟草内部的SOD活性变化有关。更多还原

【Abstract】 Sterile seedlings were cultured from the seeds of tobacco (Nicotiana tobacum L.) K326 which was an improved variety and was widely extended in our country. Their leaves were cut in small pieces and cultured to plantlets. Then the plantlets were induced by 2,4-D (0.3mg/L) and infected by R. sp. vigna 512 (5×108/L), and produced a large quantity of para-nodules on their root surfaces in a liquid medium. Finally, the SOD activity in the roots, shoots and leaves of the plantlets was determined by spectrophotometry method in different times. Results showed that in 1-5 weeks, the SOD activity in the nodulation tobacco plantlets was different in different organs, the SOD activity in the leaves was the highest, that in the roots was the lowest. No the times of the highest SOD activity in different organs were same, it in the leaves and roots was in the second week, it in the shoots was in the third week. It is not so, the SOD activity in the tobacco plantlets also had relation to the growth times, at the early stage (1-2 weeks), it was gradually rise, after 2 weeks it initiated decline. At the early stage the growth of the tobacco plantlets was normal, no they had obvious change in morphology, but after forming a large quantity of para-nodules (3-5 weeks), their growth was inhibited and presented a senescent phenomenon which was gradually income with time in degree simultaneously. The appearance of the phenomenon might have relation to the changes of the SOD activity in the nodulation tobacco plantlets.更多还原