Xiong Zhi-ting

Effect of Cadmium and Herbicides on the Growth, Chlorophyll and Soluble Sugar Content in Rice Seedlings

To investigate the combined effects of Cd2+ (0, 10, 100, 500 μmol/L), acetochlor (AC) (0, 1.6, 4.0, 8.0 μmol/L), and bensulfuronmethyl (BSM) (0, 0.16, 0.40, 0.80 μmol/L) on the biomass, leaf soluble sugar, total chlorophyll (chl) content, chl a/b ratio, and Cd content in roots and shoots in the rice seedlings, pot culture experiments were conducted with rice (Oryza sativa L.) cultivar Jinyou 402. The results showed that the Cd and AC combined treatment (Cd+AC treatment) significantly inhibited the growth of the roots and shoots. The root dry weight/shoot dry weight (RDW/SDW) ratio, total chlorophyll content and chl a/b ratio decreased by 41%, 50%, 56%, respectively, in comparison with the control, as well as the leaf soluble sugar content, plant dry weight/plant fresh weight (PDW/PFW) ratio increased by 284% and 44%, respectively. Cd content in the roots and shoots had a decreasing tendency with the increasing concentration of AC under the Cd+AC treatment. The Cd and BSM combined treatment (Cd+BSM treatment) had a similar result to the Cd+AC treatment. The results suggest that the toxicity of Cd to rice seedlings has been enhanced due to its combination with herbicides.

Effects of Zn Stress on Zn Accumulation and Anti-Oxidant Enzymes Activity in Four Varieties of Ryegrass

We investigated the influence of different content of Zn2+ (0, 2, 4, 8, 16 mmol·kg1) on plant growth, activities of peroxidase (POD) and superoxide dismutase (SOD), free proline content and Zn accumulation in four varieties of ryegrass (Loliurn pereme L.) by pot culture experiment. The results showed that plant biomass increased at the ranges of 0–2 (Tuoya). 0–4 (Yeying), 0–8 mmol·kg1 (Airuisi and Taide), respectively, and then decreased under excess Zn. The activities of POD, SOD and proline content in shoots decreased firstly, and then increased with the increase of Zn content. The plant biomass, activities of POD and SOD in Taide were evidently higher than in the other three varieties. Root tolerance index (RTI) and Zn transport ratio from root to shoot (S/R) in Taide were excced 1.0. The maximum of Zn content was 583.9 mg/kg (at 16 mmol·kg1) in Taide’s shoot.