Study On The Population Quality And Lodging Resistance Of Hybrid Rice Jinyou527 In The High And Low Altitude Regions

With three-line Hybrid Rice Jinyou527 as materials, in the low altitude region Ya'an (600m),high altitude region Xichang (1590m). Studies were conducted on the effect of differentnitrogen fertilizer and transplanting density to the population quality and lodging resistance ofHybrid Rice Jinyou527. The results were as follows:(1) With different ecological environment, the high-yield measures of nitrogen fertilizer andtransplanting density on Jinyou527 varied. In Ya'an with Medium-Low Altitude, the nitrogenfertilizer tended to medium, the suitable pure Nitrogen Application was 135kg/ha. thesuitable transplanting density was 18.75×10~4 hole/ha; While in high-altitude Xichang,high-nitrogen fertilizer and high density were more suitable. The suitable pure nitrogenapplication was 225kg/ha, the suitable transplanting density was 30×10~4 hole/ha; It wasbetter for Jinyou527 in Ya'an to take the rare-planting and panicle weight types cultivationtechnique with 280×10~4/ha effective panicle. While in Xichang area it should plant closely toimprove the seed rate on the basis that a certain number of effective panicle was arrived. Thenumber and weight of panicle were both important to high-yield. Its suitable effective paniclewas above 350×10~4/ha.(2) With different ecological environment, the population quality of Jinyou527 varied. Inhigh-altitude Xichang, their ears forming rate and spikelets, grain-leaf ratio, the single stemweight at heading stage, dry matter at heading and mature stages and the contribution rate ofdry matter before heading stage to yield were all higher than those of low-altitude Ya'an.While the LAI, photosynthetic capacity and the ratio of dry matter form heading to maturingstage to dry matter of maturing stage were all lower than those of Ya'an.The analysis of population quality index showed that: In Ya'an the source (leaf area) waslarge but feeble. The light permeating rate of base was poor especially under high nitrogenfertilizer and high transplanting density. The relation between LAI at heading stage and grainyield showed a quadratic equation. Rational application of nitrogen and low-density planting,improving LAI photosynthesis and enlarging effective leaf area ratio, controlling the length ofthe upper three leave can get strong source and big spike and then high yield. In Xichang, theSink was large while source was small, larger angle and broader leaf was useful to capturelight. The measures of increasing density and nitrogen properly can improve LAI andphotosynthetic capacity at heading stage which could increase the source.(3) With different ecological environment, the lodging resistance of Jinyou527 varied. InXichang, compared with Ya'an, there were low plant, strong stem, substantial internodes, big culm type index. The content of starch, cellulose, lignin in stem-sheath was high. Theproportion of N and K was low. There were large fracture resistance force, small lodgingindex and the lodging resistance was superior to that of Ya'an apparently.21days after full-heading was the most possible time for rice in Ya'an to lodge. 200 wasthe critical point of lodging index. The population with lodging index about or above 200more or less lodged. When LAI of heading stage and maturing stage were large than 8.63, 4.7respectively, Single-stem Weight of heading stage was smaller than 2.21g, the dry matter ofmaturing stage and heading to maturing stages were larger than 19.6t/ha and 8.0t/harespectively, lodging index was larger than 200, it were possible for Jinyou527 to lodge.In Xichang, the lodging index of all treatments did not reach the in critical point and therice did not lodge. So its goal of population construction was high-quality and high-yield.(4) The effect of nitrogen fertilizer and transplanting density to the population quality andlodging resistance was remarkable. With the increase of nitrogen fertilizer and transplantingdensity, the population of Jinyou527 became large, individual quality and light permeatingrate of base decreased. Their basal internodes became skin and long, the grain plumpnessdecreased and the content of starch, cellulose, lignin in stem-sheath decreased. The proportionof N and K was not coordinative. For middle and trace element, the content of Mg increased,Ca, Cu decreased. The culm type index decreased, the lodging index became large and therisk for population to lodge increased.