Broccoli Susceptibility To Metal Nanoparticles In Soil Enviroment

In this experiment, broccoli, a kind of vegetable which has the oxidation resistance has been adopted as a subject. We would explore the changes in the early observation index and the glycosidase of the broccoli which has been affected by the Ti O2 and Ce O2 in the soil. We would also pay close attention to changes in PH index in rhizosphere soil, total nitrogen, total carbon,ammonia nitrogen content and microbial community structure in rhizosphere soil. We expect to find out the biological effect on broccoli from Ti O2 and Ce O2 as well as the interactions between plants and soil microorganisms.The research results lie in the following several points:(1)Nanoparticles of Ti O2 and Ce O2 effect on broccoli during the seed germination and growth period. The experiment shows that there is no obvious effect on broccoli about the seed germination rate, but it will delay the seed germination. Nanoparticles of Ti O2 and Ce O2 have been absorbed by Broccoli seedling at different levels. The concentration of 200 mg/L of nanoparticles Ti O2,Ti has been absorbed most, with the increased concentration of the nanoparticles, the absorption of the broccoli decreased.The reasons for the fact may be due to the reunion phenomenon in 500 mg/L of nanoparticles Ti O2.With the increased concentration in nanoparticles of Ce O2 exposed to the broccoli,the Ce content in broccoli seedling would also rise. And through the transmission electron microscope and X-ray energy spectrum analysis, we found that nanoparticles Ti O2 and Ce O2 would enter the roots of the broccoli seedling.(2)Under the same concentration of nanoparticles Ti O2 and Ce O2 exposure, levels of the soluble sugar content that broccoli seedling root has secreted varies.Soluble sugar would increased with the increased exposure of the nanoparticles Ti O2 and Ce O2 processing, soluble sugar increased most significantly then the nanoparticles Ti O2 and Ce O2 exposed at the level of 60 d.(3)With the increased exposure time of the nanoparticles,the PH index of soil under the same concentration of the Ti O2 and Ce O2 processing can be increased significantly. There are some difference of p H index changes between Ti O2 and Ce O2 with same exposure time and same concentration. Different nanoparticles exposure have different effect of soil carbon content, with the increase of exposure time, there are more carbon in soil. Under the exposure of Ti O2 and Ce O2,60 d with the highest content of nitrogen.After 60 days, 500 mg/L nanoparticles was exposed 40 days increased 57.89% and 4.19%.Under the exposure of Ti O2 and Ce O2,ammonia nitrogen will decline with the increasing exposure time. Under the same concentration of the exposure of T i O2 and Ce O2, germ and fungus will getting more with time going.(4)The 16 S r DN A sequencing shows that soil bacteria are various with different Ti O2 and Ce O2 concentration to analyze how the exposure of Ti O2 and Ce O2 affected root soil bacteria community structure variety. The result shows, when Ti O2 and Ce O2 exposed, root soil bacteria ACE and C hao 1 index increased, there will be some increase in soil variety index. Which means the exposure of Ti O2 and Ce O2 enrich bacteria community and variety. As shown in the analysis, root soil bacteria community structure variety could be affected by different exposure of Ti O2 and Ce O2.(5)High performance liquid chromatography examined three kinds of glucosinolate, 4MTB, I3 M and 4MTI3 M in Broccoli seedling dealt with Ti O2 and Ce O2. Control only existed 4MTB. Different concentration Ti O2 exposure makes different glucosinolate content. Glucosinolate reflects most obvious when Ti O2 exposure concentration is 500 mg/L, compared with the other team, it increased about 172.13%. More concentration Ce O2 exposure means declines of glucosinolate in broccoli seedling and increased when Ce O2 concentration is 500 mg/L.