Effect Of Different Seedling Density And Nitrogen Application On Yield And Quality Of Two Wheat Varieties With Different Spike Type

The regulation effect of seedling density and nitrogen application on yield and quality of two wheat varieties, Yannong 19 characterized as huge-spiked and Lankao aizao 8 as multi-spike type, was conducted at field. The resulted indicated that:1. Effects of seedling density and N application proportion on population quality of the different spike type wheatThe productive spike ratios of 2 varieties both reduced with higher basal/topdressing ratio of nitrogen application. Leaf area index of Yannong19 was highest on middling Seedling density treatment, following as high density, and the least low density. At same density, the LAI of Yannong19 was highest at 5:5 N basal/topdressing ratio treatment. The LAI of Lankao aizao8 was increased with increasing seedling density. At low and middle seedling density, the LAI was higher at 5:5 N application, but at high seedling density, the LAI was the highest at 7:3 N application.The DM accumulations of 2 varieties were both increased with increasing seedling density. DM deposit, the amount of DM flow from vegetative organ to seed, and its contribution ratio to grain weight of Yannong19 was the highest at 5:5 N application. But of Lankao aizao9, DM deposit, the amount of DM flow from vegetative organ to seed, and its contribution ratio to grain weight achieved the highest value at 5:5 N application on the conditions of low and middle seedling density, or 7:3 N application at high seedling density treatmeng.2. Effect of seedling density and N basal/topdressing ratio on aging of wheat flag leafSOD activity was higher, and MDA content was lower on both varieties flagleaf treated with middle seedling density at 5:5 N application. It suggested that proper density and suitable N basal/topdressing ratio was effectively delay flagleaf aging.3. The effect of Seedling density and N application proportion on Photosynesis ability of different wheat variety with different type spikeThe SPAD value achieved the peak at 5:5 N application in Yannong19, a multi-spike style variety, regardless of various seedling density, and the SPAD value of middle and low seedling density treatment was higher than that of high density treatment. The SPAD value of Lankao aizao8, a huge-spike variety, achieved the peak on middle or low seedling density plus 5:5 N application treatment, whereas for high seedling treatments, the SPAD value was the highest under 7:3 N application treatment. The SPAD value of middle and high seedling density treatment was higher than that of low density treatment.Seedling density and N basal/topdressing application could effectively regulate the flagleaf photosynthesis capability of both varieties. For Yannong19, the effect intension of density to photosynthesis capability of upper three leaf were ranked as middle density>low density>high density. The photosynthesis was higher for the upper three leaves when the ratio of base and top-dressing nitrogen fertilizer was 5:5. And for Lankao Aizao8, the effect ranking of seedling density to photosynthesis capability was medium density> low density > high density. The influences of N fertilizer on photosynthesis performance of flag and top second leaf were: the biggest photosynthesis performance was present at treatment of 5:5 base/top-dressing nitrogen fertilizer under medium and low density, however, the biggest photosynthesis performance appeared at treatment of 7:3 base/top-dressing nitrogen fertilizer in high density. The effect ranking of density to photosynthesis performance of top third leaf was: low density> medium density > high density. 5:5 or 7:3 base/top-dressing nitrogen fertilizer showed relatively high photosynthesis intensity under various density.4. Effects of density and nitrogen base/top-dressing ratio on grain yield and yield formation factor in the two different spike-type varietiesRegardless of spike-type, the output of low-density treatment was lower than medium and high-density treatment. For Yannong 19, in medium density treatment, the output would reach the highest on t5:5 nitrogen basal/top-dressing application. As Anhui huaibei plain was the rain raised wheat production region, N starter fertilizer should not be less than 50%. And for Lankao Aizao8, ear number per unit and kernel number per ear and 1000-grain weight were relative coordinational at the treatment of high density combined with the 7:3 basal/top-dressing nitrogen application5. Effects of different density and N fertilizer based topdressing proportion on quality of the two spike- type wheat varietyFor Yannong19 wheat, 5:5 and 4:6ratio of base and top-dressing nitrogen fertilizer was superior to 7:3 treatment in improving protein content, wet gluten content, Z-sedimentation value, bulk density. Water content, protein content, and sedimentation value increased along with the increasing seedling density. Wet gluten content, hardness, bulk density decreased along with the increasing density. The most of flour qualities, such as amylopectin content, peak viscosity, low viscosity, RVU, last viscosity, rebound value, and so on, showed higher mean value at the treatment of 5:5 base/top-dressing nitrogen fertilizer in various density. Medium density plus 5:5 basal/top-dressing nitrogen fertilizer treatment could obtain good quality and high output for multi-spike type wheat in Huaibei region.For Lankao Aizao8 wheat, 5:5 basal/top-dressing nitrogen fertilizer or 4:6 ratio was superior to 7:3 in improving wet gluten content, Z-sedimentation value, hardness, bulk density. The treatment of 5:5 basal/top-dressing nitrogen fertilizer in various density acquired a high mean value in amylopectin content, and assorted good quality with high output. Yield and quality performed better on the treatment of medium density plus 5:5 basal/top-dressing nitrogen fertilizer.6 Effects of density and N fertilizer based topdressing proportion on stalk lodging of the two type wheatFollowing the increasing density and the decreasing N basal/topdressing ratio, the wheat plant height, the first internode length, the second internode length, the top second internode length and height of center of gravity would also increased. The second internode diameter, stem wall thickness, mechanical strength, internode plumpness, culm lodging-resistance index reduced following increasing density and decreasing N basal/topdressing ratio. Culm lodging-resistance index was closely corelated with second internode diameter, stem wall thickness, height of center of gravity and internode plumpness significantly(P<0.05). Each index of Yannong19 wheat was less than that of Lankao Aizao8, such as second internode external diameter, stem wall thickness, mechanical strength, internode plumpness, culm index lodging-resistance index, and so on. It suggested that Lankao Aizao8 is superior to Yannong19 in lodging resistance.