Effect of cadmium stress on yield and yield components of different wheat genotypes

To investigate the effect of the soil Cd concentration on yield and yield components of different wheat genotypes, a pot culture experiment was performed. Six highCd accumulating wheat (HCA) and five lowCd accumulating wheat (LCA) were used under 028 (CK), 5, 10 and 20 mg/kg soil Cd concentrations. The wheat yield decreased gradually and significantly with increasing Cd concentration in the soil, and the 1000grain weight (TGW), tiller number, spikelet number and kernel number per spike decreased gradually, while the effective tiller number increased significantly in the 5 mg/kg treatment, but was reduced significantly at higher soil Cd concentrations. The correlation and path analysis procedures were utilized to investigate the effect of Cd stress on yield and yield components of the different wheat genotypes. The results showed that Cd in the soil can easily lead to significantly reduced wheat yield, mainly because of shriveled grains and empty seeds, which suggested that Cd may affect fertilization or pollination, and growth of the embryo or endosperm. In addition, the yield, spikelet number per spike and kernel number per plant of HCA genotypes were significantly lower than those of LCA genotypes under the four different soil Cd concentrations, TGW was unchanged between HCA and LCA, while the effective tiller number of the former was higher than that of the latter.