Effects Of Different Models Of Cultivation Management On Nitrogen And Carbon Metabolism And Grain Yield In Winter Wheat

In order to provide suitable theoretical basis and technical approach for the high and stable yield of winter wheat, under the field conditions, the effects of different models of cultivation management on plant growth, nitrogen and carbon metabolism and grain yield in winter wheat were studied at Wenxian country of Henan Province during the two years of 2008-2010. Four treatments with different cultivation strategies, farmers'traditional management (CK), lower adjusted management of optimized cultivation (A1), routine management of optimized cultivation (A2), upper adjusted management of optimized cultivation (A3), were established. In this experiment wheat cultivars of Pingan 8 was taken as planting material to determined the effects of different models of cultivation management on population culms, dry matter accumulation, photosynthesis characteristics, nitrogen and carbon metabolism, nitrogen utilization efficiency and grain yield. The main results were as follow:1. During the two years population culms dynamic under different models of cultivation management was the same trend with taking on single peak and reaching at jointing. During growth season of 2008-2009 the population culms of CK was the highest before jointing stage with being followed by A3 and A2. During growth season of 2009-2010 the population culms of CK was the highest with being followed by A1. The results showed that the dry matter accumulation increased gradually with the growth stage, reached the maximum at the maturity during the two years. the dry matter accumulation was the highest in the treatment of CK from overwintering to jointing, and in the treatment of A3 from anthesis to maturity with being followed by A2 during two growth seasons.2. During the two years chlorophyll content in different models of cultivation management were the same trend, with taking on single peak and reaching the maximum at 7 day after anthesis and then decreased. During growth season of 2008-2009 chlorophyll content in the treatment of A3 was the highest during 0-21 days after anthesis with being followed by A2. During growth season of 2009-2010 chlorophyll content in the treatments of A2 and A3 was higher with no significant difference between above two treatments. During the two growth seasons the photosynthesis decreased gradually with growth stage. During growth seasons of 2008-2009 the photosynthesis in the treatment of A2 was the highest at anthesis and 28 day after anthesis with being followed by A3. During growth season of 2009-2010 the photosynthesis in the treatment of A3 was the highest during 0-21 days after anthesis with being followed by A2.3. During the two years changes of sucrose content and soluble content in flag were the same trend with growth stages under different models of cultivation management, with first increasing and then decreasing. During growth season of 2008-2009 the sucrose content in treatment of A2 was the highest before 14 days after anthesis with being followed by A3, and the soluble content of A3 was the highest during 14-35 days after anthesis with being followed by A2. During growth season of 2009-2010 the sucrose content of A3 was the highest in the sampling stages with being followed by A2, and that of CK was lowest. The soluble content of CK was the highest before 14 days after anthesis with being followed by A3, and that of A3 was the highest after 14 days after anthesis with following by A2. During the two years the sucrose content and soluble content in grain decreased gradually with the growth stage under different models of cultivation management. The sucrose content was higher in the treatments of A2 and A3 with no significant difference between above two treatments, and the lowest in the treatment of CK, and the soluble content had opposite trend. During two growth seasons SPS and SS activity had the same trend under different models of cultivation management, with single peak with growth stages. The SPS and SS activity was higher in the treatments of A2 and A3 with no significant difference, with the lowest in the treatment of CK during the two years. The above results showed that optimal cultivation management could maintain relative high activity in the grain filling, effectively improve the sucrose content and soluble content in both flag and grain, and provide adequate material for starch synthesis.4. During the two growth seasons NR and GS activity were decreased gradually with the growth stages under different models of cultivation management. The NR activity in the treatments of A2 and A3 was higher with no significant difference, and the GS activity of A3 was the highest with being followed by A2 during the two years. The results showed that optimal cultivation management could maintain relative high NR and GS activity, and promote the nitrogen uptake and accumulation. The plant nitrogen uptake decreased with nitrogen fertilizer increased under different models of cultivation management during the two years. During the two years the NUPE in the treatment of A1 was the highest with being followed by CK, and the NUTE in the treatments of A2 and A3 was higher with no significant difference between A2 and A3, and the lowest in the treatment of CK. The AE showed the different tendency of A1>A3>A2>CK in 2008-2009 and CK>A2>A3>A1 in 2009-2010. The PFP showed the same tendency of A1>CK>A2>A3 during the two growth seasons. The PE and IE showed the same tendency of CK>A1>A2>A3 during 2008-2009, and the PE and IE of A2 was the highest, and the lowest in the treatment of A3 during 2009-2010.5. During the two years the effects of different models of cultivation management on grain yield was important, optimal management could significantly increased the grain yield. The spike during two growing seasons showed the different tendency of A2>A3>A1>CK in 2008-2009, and CK>A1>A3>A2 in 2009-2010. Grains per spike in the treatments of A2 and A3 was higher, with the lowest in the treatment of CK during the two years. During the two years the 1000-kernel weight and grain yield showed the same tendency of A3>A2>A1>CK. The yield of A3 and A2 was significantly higher than CK, with no significant differences between A2 and A3. According to the above results, the treatment of A2 and A3 could effectively coordinate the relationship between yield components and increase grain yield, and A2 was better cultivation measure in wheat production based on yield and economic benefit analysis.