Studies On Effects Of Different Ratios Of Different Nitrogen Source On The Growing Development And Regulations Of Grain Yield And Quality In Wheat (Triticum Aestivum L.)

Improving grain yield and quality of wheat cultivars is now one of the key subjects. Applying organic manure has the dual role in improving soil structure and providing nutrients to plant and has been one of important methods to regulate the growth and development of crop. Thus, root room experiments, root box experiments and field experiments were completed on a sandy loam at Henan Agricultural University Experimental Station during 2005-2008, respectively. A strong gluten wheat cultivar-Yumai 34 was used in experiments. Equal amounts of nutrient in different fertilizer types were urea, chicken manure or in mixed forms where the ratio of urea to chicken manure was 75:25, 50:50, 25:75, respectively. Effects were studied of different(or mixed) types of fertilizer on the growth and demise of wheat root, root spacial distribution, on rhizospheric microbial population and activity of soil enzymes, on light distribution characteristics of the canopy and leaf photosynthetic characteristics, on nitrogen utilization efficiency, on the grain yield and quality, in the hopes of providing academic and practical basis for application of different ratios of nitrogen source in controlling wheat yield, protein content and the composition of grain protein. Details are as follows:1, In use of the minirhizotron root monitor system, root parameters(root length density, root increment, root mortality and turnover) were studied in 0-140 cm soil layers, under different fertilizer treatments(urea, chicken manure, and their applying ratio 75:25, 50:50, 25:75). The result showed that root length density decreased gradually with the out shift of the location relative to wheat row, but in 0-60cm soil layers root length density declined firstly and ascended afterwards in 60-140cm layers, and in 0-50cm soil layers, the root length density gradually increased with the advance of growth stage, but in 50-140cm soil layers, root length density changes varied with the advance of Growing stages; root diameter showed an increasing trend with the decrease of the soil depth, and reached a peak value in the entire reproductive period in 80-90cm soil layer; root increment and mortality showed a trend of gradual decrease with the increase of the soil depth; the root periodic turnover of both increment and mortality became lower firstly and then increased with the increase of soil depth.Different ratios of nitrogen source can increase root length density in different soil layers, and the effect of different nitrogen source equivalent ratio treatment was the largest and significantly higher than other treatments; different ratios of nitrogen source was conducive to the enlargement of the diameter of wheat root; comparing with the contrast(A₀) and urea treatment(A₁), the equivalent ratio treatment of different nitrogen source had a significant increase in root incement and mortality; equivalent ratio treatment of different nitrogen source can also significantly increase the average root length density, and the turnover of root increment and mortality.2, With root box method, we had studied the effects of urea and chicken manure, and their equivalent fertilization(50:50) on wheat root growth, the aging course and nitrate content of soil. The results showed that application of chicken manure significantly increased the density of wheat root weight and root volume density, the root weight density and root volume density both in row and between the rows decreased significantly with the deepening of the soil, but decreased after an increase with the out shift of birth period, and became the largest in anthesis stage; with the increase of the proportion of organic manure application, root number increased firstly and decreased afterwards, the equivalent ratio treatment of different nitrogen source was the largest; root activity reached maximum value in booting stage, and gradually decreased with the increase of the soil depth, equivalent ratio treatment of different nitrogen source also produces the highest in comparison of other treatments; in different soil depth, changes of SOD activity of root in entire reproductive periods showed as follows: equivalent different ratios of nitrogen source > organic manure> urea; MDA content of root in the entire reproductive period showed as follows: urea > organic manure> equivalent different ratios of nitrogen source. Nitrate content of soil in the 0-20cm layers was the highest under the equivalent ratio treatment of different nitrogen source . In the 20-60cm soil layers, nitrate content was higher in the organic manure treatment or different ratios of nitrogen source treatments than urea treatment before winter. However, from the beginning of booting stage, nitrate-N content in the 20-60cm soil layers became lower in dealing with fertilization of equivalent different ratios of nitrogen source than urea treatment, especially significant lower in 40-60cm soil layers.3, Through field experiments in randomized block design, the effects of urea, chicken manure and the different fertilizers proportion(the ratio of urea to chicken manure was75:25,50:50,25:75 respectively) on soil respiration rate in wheat field and biological activity of rhizosphere soil were studied in this paper. The results showed that soil respiration rate gradually increased with the ratio increase of organic fertilization in Before wintering and returning green stages, and highest uder organic fertilization treatment, but first rised and reduced afterwards from jointing period to mature period, highest under equivalent ratio treatment of different nitrogen source . From anthesis stage to mature stage, the soil respiration rate increased significantly under equivalent ratio treatment of different nitrogen source in comparison with urea treatment; soil moisture and soil temperature increased firstly and decreased afterwards with the proportion increase of the organic manure application, highest uder under equivalent ratio treatment of different nitrogen source ; the number of fungi was largest under the treatment of proportion of 75:25 Before wintering stage and during the period of returning green, and largest under under equivalent ratio treatment of different nitrogen source in the period from booting to mature stage; in jointing stage, grain filling and mature period, the number of bacteria wass significant larger under under equivalent ratio treatment of different nitrogen source than other treatments; the number of actinomycetes gradually increased with the increased application of organic manure in before wintering and returning green stages, increased firstly and then decreased from jointing period to maturity period; soil urease activity significantly increased under the treatment of 75:25(urea to organic manure) ratio and stronger than other treatments; Zymose activity was strongest under the treatment of 75:25(urea to organic manure) ratio from Before wintering to grain filling stages, and the difference with other treatment was significant; with the same portion of fertilization, polyphenol oxidase activity was strongest in anthesis stage, but in other periods, strongest polyphenol oxidase activity under equivalent ratio treatment of different nitrogen source ; results of correlation analysis between soil respiration rate and other soil indicators showed that the relation of soil respiration rate and soil temperature was the strongest, showing significant or highly significant positive correlation, and soil respiration rate was significantly and positively correlated with the number of actinomycetes.4, In the use of field experiments, effects of urea, chicken manure and different ratios of urea to chicken manure (75:25,50:50,25:75) on nitrogen efficiency of wheat were studied in this paper. The results showed that grain nitrogen and nitrogen content increased firstly and then decreased with the increase of organic fertilizer application, highest value appeared under the treatment of 75:25(urea to organic manure) ratio in Before wintering stage, in the other Growing stages, highest value appeared uder the treatment of equivalent proportion (50:50); different ratios of nitrogen source treatments can increase nitrogen fertilizer use efficiency and agronomic nitrogen use efficiency, but not conducive to improving nitrogen use efficiency; the equivalent ratio treatment of different nitrogen source can significantly increase nitrogen accumulation in the Stalk during the anthesis and mature stages, and significantly improve the efficiency of nitrogen transfer, and under equivalent ratio treatment of different nitrogen source , the nitrogen transfer efficiency was highest.5, The study was conducted to reveal the effects of different ratios of nitrogen source on canopy architecture of Yumai34. Field experiments with the conventional "Layer upon layer cut method" were carried out to study the dynamics of canopy architecture characters of Yumai34 after application of urea, urea and chicken manure mixed ,and chicken manure alone. The results showed that chlorophyll content (SPAD value) in flag leaves, photosynthetically active radiation (PAR), mean leaf angle(MLA), and leaf area index( LAI) increased under chicken manure applied, while canopy openness(DIFN) behaved oppositely, and these were all helpful to improve the light utilizing efficiency. The mixed fertilizer treatment had a reasonable canopy architecture than others, which accounted for they had intercepted more solar radiation.6, Field experiments were conducted to clearify the effects of urea, chicken manure and different ratios of urea to chicken manure (75:25,50:50,25:75) on photosynthetic characteristics of different wheat leaves.This study indicated fertilization can significantly improve the leaf area per plant, SPAD value, net photosynthetic rate, stomatal conductance, transpiration rate, stomatal limitation value and water use efficiency in every reproductive period of wheat, and reduce intercellular CO₂ concentration, and with the increase of organic manure in application proportion, with the exception of intercellular CO₂ concentration which decreased firstly and then increased, other indicators all showed an inverse trend, and the effects of equivalent ratio treatment of different nitrogen source was most significantly.7, Field experiments were conducted to study the effects of urea, chicken manure and different ratios of urea to chicken manure (75:25,50:50,25:75) on wheat grain yield and quality. The results showed that in contrast to no fertilizer treatment and urea treatment respectively, different ratios of nitrogen source treatments can significantly increase the number of wheat root, the number of effective tillers, grains per spike, grain weight per spik, economic yield, Harvest index and protein content, furthermore, the economic yield, Harvest index, glutenin/gliadin ratio and albumin protein and glutenin content all reached the highest value under the equivalent ratio treatment of different nitrogen source , and more significantly or extremly significantly higher than treatments. Considering the general factors such as wheat grain yield, Harvest index, protein components, the equivalent ratio treatment of different nitrogen source was the best, and it had the highest wheat grain yield, a reasonable protein components and the best quality.