二甲戊灵胁迫对伊乐藻生理特性的影响

Effects of Pendimethalin Stress on Physiological Characteristics of Elodea nuttallii

本研究采用水培试验方法研究不同浓度二甲戊灵对伊乐藻植株叶绿素含量和2种抗氧化酶活性,以及丙二醛(MDA)、可溶性蛋白(SP)及脯氨酸(Pro)含量的影响。结果表明,(1)二甲戊灵可以抑制伊乐藻叶绿素a合成,促进叶绿素b合成,降低植物体光合能力;(2)在试验浓度范围内,伊乐藻SOD活性均低于CK,除第2天F处理(4 mg·L^(-1))外,其余各组SOD活性在各测定时间内表现为浓度越高SOD活性越低;随着二甲戊灵浓度的升高,第2天时,除F处理(4 mg·L^(-1))外,其他各组伊乐藻POD活性与CK无显著差异,第4,6,8天,POD活性先升后降,第10天则呈降-升-降的趋势;(3)处理后第10天,随着二甲戊灵浓度的增加,伊乐藻体内丙二醛(MDA)和脯氨酸(Pro)含量先升后降,分别至1 mg·L^(-1)和2 mg·L^(-1)达到最高,可溶性蛋白(SP)含量呈降低-升高-降低的趋势,且各处理均显著低于CK。上述结果均说明二甲戊灵影响了伊乐藻正常的生理代谢活动。

The experiment was conducted with the hydroponics method,and the effects of different concentrations of pendimethalin on physiological characteristics of Elodea nuttallii were studied,including chlorophyll content,two kinds of antioxidant enzyme activities,and the content of malondialdehyde(MDA),soluble protein(SP)proline(Pro)in the plant.The results showed that,under the pendimethalin treatment,the synthesis of chlorophyll a was inhibited,while the synthesis of chlorophyll b was promoted,the plant photosynthetic capacity was reduced.In the range of experimental concentration,the activity of SOD activity was lower than that of CK,and the SOD activity showed that SOD activity was lower when pendimethalin concentration was higher in each test time except for the 2nd day of F treatment(4 mg·L-1).With the increase of pendimethalin concentration,on the 2nd day,except for F treatment(4 mg·L-1),the activity of POD activity in other groups had no significant difference with CK,on the 4th day,6th day and 8th day,the activity of POD first increased and then decreased,on the 10th days,the activity of POD showed a decrease-increase-decrease trend.On the 10th day after pendimethalin treatment,with the increase of pendimethalin concentration,the content of malondialdehyde(MDA)and proline(Pro)increased first and then decreased,and reached the highest level under 1 mg·L-1 and 2 mg·L-1 treatment respectively,soluble protein(SP)content showed a decrease-increase-decrease trend,and all treatments were significantly lower than CK.All these results indicated that pendimethalin affected the normal physiological and metabolic activities of Elodea nuttallii.