Effects of foliar application of micronutrients on concentration and bioavailability of zinc and iron in wheat landraces and cultivars.

Foliar application of micronutrient is a rapid and promising strategy to enhance the concentration and bioavailability of micronutrients in wheat grain. To explore the effects of foliar application of micronutrients on the concentration and bioavailability of zinc and iron in grain in wheat cultivars and landraces, field experiments were carried out using 65 wheat cultivars and 28 landraces to assess the effects of foliar application of zinc (iron) on phytic acid concentrations, zinc (iron) concentrations and their molar ratios. The results indicated that mean grain zinc concentration of landraces (44.83 mg kg-1) was 11.13% greater than that of cultivars (40.34 mg kg-1) on average across seasons, while grain iron concentration did not differ significantly between landraces (41.00 mg kg-1) and cultivars (39.43 mg kg-1). Foliar zinc application significantly improved the concentration and bioavailability of zinc in grains in both cultivars and landraces, while landraces had almost two-fold more increase in grain zinc and also greater improvement in zinc bioavailability compared to cultivars. While foliar iron application did not significantly affect iron concentration and bioavailability in grains in either cultivars or landraces. Our study showed that, with foliar application of zinc but not iron, wheat landraces had better performance than cultivars in terms of the increases in both concentration and bioavailability of micronutrient in grains.

[Effect of folate on the proliferation of human cervical cancer cell and relationship with HPV16].

OBJECTIVE: To study the effect of different concentration of folate in vitro on the proliferation and apoptosis of C33A cell with HPV negative and CaSki cell with HPV16 positive, and intreaction of folate and HPV16. METHODS: C33A and Caski cells were intervened by different concentration of folate (0.1, 1.0, 10, 50, 100, 500, 1,000 and 2,000 microg/ml). The morphological changes of cells were examined by reverse discrepancy microscope. MTT and Flow Cytometry (FCM) were employed to measure the proliferation, inhibition ratio, cell cycle and apoptosis of cells. RT-PCR was used to detect the expression of HPV16 E2/E6 oncogene. RESULTS: The effects of folate on the C33A and CaSki cell growth suppression were increased gradually with the concentration of folate increasing and cultured duration prolonging, the inhibition ratio was increased (C33A: r = 0.948, P = 0.010; CaSki: r = 0.895, P = 0.006). Adding folate could induce cell apoptosis (C33A: r = 0.989, P < 0.001; CaSki: r =0.994, P < 0.001), and there was a linear relationship, but there was no significant difference on the proliferation and apoptosis of C33A and CaSki cells effected. In addition, concentration of folate did not affect the expression of HPV16 E2/E6. CONCLUSION: Different concentration of folate inhibited cervical cancer cell proliferation and enhanced cell apoptosis, but the results do not support an interaction between folate and HPV16 in cervical cancer cell.