Research On Rice Growth Characters And Yield Structure Under Different Density And Seedling-age

Based on current rice production condition of Northeast China, in order to make farmers operating possibly, the cultivation technique's feasibility which transplant compressed or sparse or little seedling-age was researched. It was done at Jilin Agricultural University Rice Production and Experiment Center in 2005, which was set 2 factors, density and seedling-age with 2 different parts - 1 seedling per carve and 2 seedlings per carve. The farmland was designed as quadratic general rotational combination design, which upper limit and floor limit are 6 - 30 carves per square meter and 2-5 seedling-ages.From recovery to harvest, there are 5 times measurers in key growth period, whose items include shape index, dry matter accumulation, chlorophyll content and soluble sugar. Net photosynthesis rate, intercellular CO2 proportion and H2O transpiration rate were measured in seed-filling stage. Yield factors were inspected after harvest, and regression analysis was done.Long seedlings-age makes seedling quality high; some long one even has tillers before transplanting. Seedling-age influences former growth in field. Long seedlings-age makes culms length and dry matter and LAI and population tillers being large.Transplantation density influences rice growth of middle and later stage in field. That density was increasing leads to rice growth and development being in advance, dry matter weight and leaf area per cave being and tillers per cave being low. Regression analysis indicates that density would have more influences on population than seedling-age would when transplanting 1 seedling per cave, the result was on opposite when 2 seedlings. Dca and Sec have high LAI; leaf area and LAI was higher with 1 seedling per cave than that with 2.One with high chlorophyll content decrease sharply. Soluble sugar content was down with density increasing. Regression demonstrated that seedling-age had more influence on photosynthesis rate than density. Inter-cell CO2 content was down with seedling-age large.The regression indicated that density has more influence than seedling-age. Theoretically, if want to get highest yield, density and seedling-age should be set at 18.60 carve/m2 and 2.8 seedling-age with 1 seedling per carve, or 16.8 carve/m2 and 4.6 seedling-age with 2. The latter method can gain more yield of 586 kg/ha than the former.