Study On Interactions Between Nitrogen And Sulfur And Sulfur Fertilizer Application On Gyain Yield And Related Protein Quality

The study concerning the effects of nitrogen and sulfur fertilizer application on wheat grain yield and quality was based on field experiment from 2011 to 2013 conducted at Lianyung Dongxin farm using wheat cultivar lianmai 2 as material. Besides, the same study was also conducted at Nanjing Tangquan Experimental Station with another wheat cultivar Yangmai 16 during wheat growth season 2012 to 2013. In this study wheat grain yield, protein and its chemical composition content were analyzed. The main results were as follows:1. Effects on grain yield and yield componetsNitrogen increased grain yield and yield components while excessive nitrogen caused a decline in spike number and kernerls per spike. Sulfur affected kernels per spike which first increased and then decreased with the increasing proportion of topdressing supply, while excessive topdressing caused a decline in the number of kernels per spike. Wheat grain yield could be affected by nitrogen fertilizer, grain yield and its components could be improved simultaneously under a reasonable amount of sulfur fertilizer basing on moderate nitrogen fertilizer. Resulting on study, we found that nitrogen rate ranging from 210 to 270kg.hm-2 with the right amount of sulfur fertilizer 67.5kg.hm"2 and dressing ration at 7:3 or 5:5 could increase wheat grain yield at greatest degree.2. Effects on content of protein and its componentsNitrogen and sulfur fertilizer increased the content of protein and its components-albumin, globulin, gliadin and glutenin significantly, Besides, with the increase amount of fertilizer, content of protein and its compositions decreased after an initial increase, the interaction of right amount of nitrogen and sulfur could reach highest protein content.GMP content had the same changing patterns as protein content and it was highest N210 with S67.5 and N270 with S67.5 treatments. The volume and surface area distribution of GMP particles were shown as two-peak-curve patterns. Both nitrogen and sulfur fertilizer reduced the first peak value and increased the second peak value, while sulfur increased the second peak and promoted the first peak to larger GMP. At the same time both nitrogen and sulfur reduced the number proportion of<12μm GMP particles and increased the number proportion of>12μm GMP particles. The number distribution of GMP particles showed a single peak curves, nitrogen enhanced the peak and sulfur-promoted the peak to smaller particles.In conclusion, both nitrogen and sulfur fertilizer increased the volume and surface area distribution of big GMP particles and the number distribution of small GMP granules. Nitrogen and sulfur trail significantly affected the content of HMW-GS, sulfydryl group and disulfide bond of grains. The content increased with increasing nitrogen and sulfur fertilizer supply while misuse of fertilizer cause the decline of content, also, they first increased and then decreased with the increasing jointing fertilizer supply, who had highest content under the topdressing of 7:3 or 5:5.3.Effect on processing qualityNitrogen and sulfur fertilizer increased gluten content and improved gluten quality Gluten quality was best under nitrogen supply 210 to 270 kg.hm-2 and sulfur fertilizer 45 to 67.5kg.hm-2,while misuse of nitrogen reduced wheat gluten quality; and it gluten content also increased with the increasing proportion of topdressing excepting exorbitant top dressing sulfur proportion. In addition, SDS-value increased with the increasing of nitrogen fertilizer supply while it changed slightly under different sulfur fertilizer application treatments.Nitrogen rate ranging from 210 to 270kg.hm-2 with the amount of sulfur fertilizer 45 to 67.5kg.hm-2 and dressing ration at 7:3 or 5:5 could not only increase protein content and wet gluten content, improve wheat quality, but also promoted the number of kernels per spike and then increased grain yield.In conclusion, interaction of nitrogen and sulfur and different sulfur fertilizer can promote yield and grain quality synchronously.