Influence of uniconazole and plant density on nitrogen content and grain quality in winter wheat in South China

Superior protein quality and consistent processing quality is needed for winter wheat marketing in South China. It has been shown that uniconazole concentration and plant density are certainly related to crop growth. An experiment was conducted to investigate the effects of uniconazole concentration and plant density on nitrogen content and grain quality in winter wheat (Triticum aestivum L.). Trials were managed to provide three levels of density (90 × 104, 180 × 104, and 270 × 104 per ha) over plots receiving four levels of uniconazole concentrations (0, 10, 20, and 40 mg/kg) which were applied to seeds before sowing. The results revealed that the contents of N accumulated in ear, stem, and leaf were higher in uniconazole concentrations than that in control, and the effect of uniconazole on main stem was bigger than that on tillers. The grain protein was significantly (LSD, P < 0.05) higher in uniconazole concentrations than that in control. Uniconazole at 20 mg/kg was the most favorable for improving grain protein and protein fractions. Application of uniconazole concentrations also significantly (LSD, P < 0.05) increased WGC (wet gluten content) and SDS (sedimentation volumes), prolonged DDT (dough development time) and DST (dough stable time), and improved WA (water absorption), increased VV (valorimeter value), and subsequently improved the processing quality of wheat grains. These results suggest that a combination of uniconazole concentration and plant density should be applied in South China.