摘要：Seven parents and their 21 Fl diallel crosses of maize were grown under field conditions in the 2001 and 2002 growing seasons on two soils mutually air-distanced 800 m （BI = fluvisol and B2 = stagnic albeluvisol; pH in KCI = 7.02 and 3.85, humus = 2.75 and 2.02, CaCO3 = 11.4% and 0, for B 1 and B2, respectively）. Also, the B 1 and B2 were differently in NH4Acetate-EDTA soluble fraction （***： calcium 25,500 and 2,300; zinc 1.61 and 0.53; cadmium 0.195 and 0.064, respectively）. The experiments were conducted in four replicates （the basic plot 16.8 m2） in a randomized complete block design. The ear-leaf was taken at the beginning of silking and grain samples at maturity. Mean leaf-Cd （mg ***-t in dry matter） were 0.102 and 0.072, for 2001 and 2002; 0.064 and 0.195, for BI and B2, while differences in level of genotype were from 0.040 to 0.581 （the parents） and from 0.046 to 0.171 （the hybrids）. Six hybrids of Bc707-1 had considerably higher leaf-Cd in comparison with six hybrids of Bc265-1 （means 0.100 and 0.050 respectively）. Grain-Cd was under detectable range （〈 0.040） with exception of Bc707-1 parent on the B2 soil （0.17 mg Cd-kg^-1）.

摘要：Experiments were designed to expose the filter-feeding bivalve Perna viridis to different Cd-contaminated water environments in order to compare the different pathways through which Cd is accumulated. Results show that mussels can accumulate Cd through seawater, food, sediment and suspended particle pathways in a short period of time. Mussels＇ uptake of Cd through the seawater pathway reaches the highest concentration approximately 3 and 9 times larger than through the algae and sediment pathways respectively after 7 d. This indicates that the Cd-accumulation through seawater is most efficient. Results also indicate that the uptake directly through contaminated algae, particles or sediments ingested by mussels is less important when compared with the uptake of Cd by mussels through the seawater pathway. Metal uptake pathways and mechanisms of bioaccumulation by marine bivalve are also discussed in this paper.