Effects Of Nitrogen Fertilizer And Density On The Yield,Population Quality And Stem Flexural Of New Plant Type Rice

In this study,we used the new plant type conventional japonicas rice JY3-693 which had been bred with IPA1 homozygous mutation and Ning1092 which had been widely used on the production for materials.The test used split-split plot design.The paper systematically studied about the effects of the yield traits,the population quality and lodging resistance traits of rice in different nitrogen,densities and seedling seed levels.The thesis also defined the application value of IPA1 and the cultivation conditions that JY3-693 got higher yield and lodging resistance traits.The main results were as follows:1.The conventional rice JY3-693 which had the IPA1 homozygous mutation has significant plant type characteristics: The JY3-693 had low tillers in single seed-seedling and the per panicle,1000-grain weight,ear length,number of primary branches were significantly greater than the Ning1092,but the average seed setting rate was significantly lower than the Ning1092 which had described that IPA1 homozygote gene has a low number of tillers,typical of the formation of large spike.The SPAD value,net photosynthetic rate,transpiration rate of flag leaf and the area of the fourth leaves about JY3-693 were significantly higher than Ning1092 which had described that IPA1 homozygote gene has a strong photosynthetic capacity,it is conducive to plant photosynthesis;The each inter-node's diameter,stem wall thickness,number of vascular bundles,machinery and parenchyma cell layers were significantly higher than Ning1092 which had described that IPA1 homozygote gene has a strong stem diameter,but the flexural of each inter-node of JY3-693 was lower than Ning1092,it may be that dry biomass per unit volume of Ning1092 was higher than JY3-693.Under the condition of the same seeding seeds,JY3-693 which was in the nitrogen level of 180kg/hm~2,which theory-yield was lower than Ning1092 and in the nitrogen level of 225kg/hm~2.Theoretical yield was higher than Ning1092 and the increasing of nitrogen fertilizer had significant effect on increasing yield of JY3-693,ti is described that IPA1 homozygotes have some yield potential,can effectively improve the rice yield.The JY3-693 had the typical characteristics of body that was over expression of IPA1 gene: low tillering,big ear and stout stem.2.The increase of nitrogen fertilizer,is conducive to effective population of spike,per panicle and the theoretical yield;It is good at to improve community effective ear with the increase of planting density,but the per panicle was reduced,and the theoretical yield of JY3-693 was the first increase and then decrease,it is not significant in different planting density,Moderate planting density can effectively increase production;With the increasing of the number of seeding seed,the panicle population was increased,but the per panicle was reduced,the theoretical yield of JY3-693 was increasing,and the difference between the numbers of levels of each seeding seed was extremely significant.3.Nitrogen increase will help improve the photosynthetic rate,effective panicles and dry matter accumulation groups;Low planting density,seed seedling level will help improve the photosynthetic rate,With the level of planting density,seed seedlings increasing,it is good to promote effective population spike and dry matter accumulation4.The significant positive correlation was between the stem lodging index and plant height.The inter-node length was negatively correlated with lodging index.The length of stem inter-nodes' long axis and short axis,stalk inter-node cross-sectional area,wall thickness of culm wall,and the cross sectional area was not significantly correlated with the lodging index,but they were extremely significant positive correlation with the flexural stress,while the inter-node thickness and inter-node flexural was not significant.The dry matter weight of per unit volume was negative correlation with lodging index but was not significant and positive correlation with inter-node flexural which was not significant.The numbers of large vascular bundle number and small vascular bundles,the mechanical tissue cell layers,thin cell layers of the basal inter-nodes were negative correlation with the lodging index which was not significant,and they were positive correlation with inter-node flexural but not significantly.It was significantly and negatively correlated between the inter-node flexural strength and lodging index.5.With the increase of nitrogen application,the bending stress of the stem basal first inter-node had increased,but the resistance of the stem basal second and third inter-node had reduced.The inter-node length had increased and the stem diameter and the dry matter weight of per unit volume had decreased,Increasing nitrogen level would be in favor of Rice Stem slender growth,accelerate the material transport;It would help reduce the length of the base stem,but not conducive to increasing stem thickness and plumpness;Increase the number of seed seedlings would help the base between the first and second section of shorter length,between the base of the third quarter longer,thicker stems,but the amount of dry matter per unit volume declined,reducing the stem plumpness.6.The cultivation conditions for the high yield and lodging resistance: In the cultivation conditions of that the application of pure nitrogen was 225kg/hm~2,the row spacing was 26.67cm*13.33 cm,and the seeding seeds were 6 seeds per hole.JY3-693 would not only could effectively increase the yield,but also can realize the stem in the high lodging resistance,the yield and lodging resistance were both taking into account.