热水处理对3种进口苗木的损伤及抗氧化酶系的影响

为了探明热水浸泡处理对进口南洋参、香龙血树和百合苗木的影响,本试验分别利用45℃60min、48℃10 min、48℃30 min和48℃60 min,4组时间和温度组合对3种进口苗木进行热水浸泡处理,然后测定处理后各供试苗木叶片中丙二醛(MDA)含量,过氧化物酶(POD)活性、过氧化氢酶(CAT)活性和超氧化物歧化酶(SOD)活性。而后对处理后各供试苗木进行复种,3周后观察复种苗木的生长情况。结果表明:3种供试苗木各处理组MDA含量均比对照组有所增加;POD活性仅有南洋参部分处理组比对照组有所增加,南洋参其他处理组以及香龙血树和百合各处理组均比对照组有明显下降;CAT活性南洋参和香龙血树各处理组与对照组之间均差异不显著,百合各处理组均比对照组有所增加;SOD活性百合各处理组相比对照组均出现了明显的下降。经过热水浸泡处理后复种的各供试苗木,南洋参和香龙血树均能够正常生长,百合均死亡。上述研究表明南洋参和香龙血树对热耐受性较高,可利用热水浸泡进行检疫除害处理,百合耐受性较差,不能采用热水浸泡进行检疫除害处理。

Effects of hot water treatment on antioxidant enzymes activities and replant survival of three imported seedlings

In order to investigate the effects of hot water immersion on three kinds of imported tree seedlings,such as Polyscias balfouiana,Dracaena fragrans and Lilium spp.,four groups of temperature and time combinations of 45℃ for 60 min,48℃ for 10 min,48℃ for 30 min and 48℃ for 60 min were used respectively to immerse the three kinds of imported seedlings in hot water,and then the content of malondialdehyde(MDA),the activities of peroxidase(POD)、catalase(CAT) and superoxide dismutase(SOD) in the leaves of each treated seedling were determined. After that,all the treated seedlings were replanted,and the growth of the replanted seedlings was observed 3 weeks later. The results showed that the MDA content increased in each treatment group of the three kinds of seedlings compared with the control group;the POD activity increased only in partial treatment group of Polyscias balfouiana,and decreased significantly in other treatment groups of Polyscias balfouiana,and in each treatment group of Dracaena fragrans and Lilium spp.;there was no significant difference in the CAT activity between each treatment group and the control group of Polyscias balfouiana and Dracaena fragrans,while the CAT activity of each treatment group of Lilium spp. increased;only the treatment groups of Lilium spp. showed a significant decrease in the SOD activity. After hot water treatment and replantation,each of tested seedling of Polyscias balfouiana and Dracaena fragrans could grow normally,and all tested seedlings of Lilium spp.died. The aboved results showed that Polyscias balfouiana and Dracaena fragrans had high heat resistance,and could be treated with hot water immersion for quarantine and disinfestation,while Lilium spp. had poor heat resistance and could not be treated with hot water immersion.