Study On The High-yield Model Of Super-sparse Cultivation On Rapessed (Brassica Napus L.)

The experiment was conducted to study the cultivate factors that effect the yield of rapeseed "HRS-1".The mathematical model of sowing time,planting density and fertilizer applied amount for plot yield of was established by three-factor-five-level quadratic orthogonal regressive rotation combination design.The result was showed as follows.1 According to the fine selection,the scheme of cultural model for yielding above 3750kg/hm² was obtained from the mathematical model as follows:sowing between August 29^th and September 2nd the whole life is 244-248 days,planting at the density of 26130-31230 plants/hm²,applying fertilizer 681.23-836.40kg/hm².2 In the single factor to the output effect analysis,the density was the biggest to its influence,sowing date and fertilizer were the next.While fertilizing at the zero-level that was 312.5kg/ha,the earlier sowing date,the higher yield with the density increased;Whereas sowing date postponed,as the density increased,there was a downward trend of the yield level.While the density was at the zero-level that was 22500 plants/ha,the earlier sowing date,the higher yield took place with the more fertilizer;Whereas sowing date postponed,as the fertilizer increased,there was a downward trend of the yield level.when sowing on 6/9 and low-density planting,increasing fertilization has little effect on the yield,however with the density increasing,the production could be increased through raising the level of fertilization.Finally,through the boundary output effect analysis,the sowing date to be supposed to take the later time,the density and the quantity fertilizer should take the higher level.3 Sowing date had the obvious influence to the period of duration,the density and the amount of fertilizer were not remarkable to the period of duration influence.There was obvious influence to the characters of rape development,such as leaves,heigt, stem-diameter,crown:all the characters increased with the earlier sowing date,lower density and more quantity of fertilizer.During the three fators,the sowing date had much more influence to the characters than others.In the suitable density scope,the agronomic characters and the output presented positive correlation,the output increased along with the enhanced agronomic characters value.The dry-weigh assignmented also shifted along with the shifted growth center.The leaf dry-weight reached to the maximizing in flower bud liver moss time.Along with the leaf decling,the dry-weigh transferred to silicle and stem,the dry-weigh t of single plant reached to the maxmium in mature period.Moreover,along with broadcasting the sowing date, density reducing,the quantity of fertilizer increased,the dry-weight increased.In these three factors,the sowing date was the most remarkable to its influence,and it was bigger than the density and fertilizer to its influence.Moreover,low density could cause the single dry-weight increased,but because of the number reduced,the ultimate output didn't have obvious superiority,along with the single dry-weight increased,the overall output also assumed the growth tendency,in certain scope,dry-weight presented positive correlation with the output.In the duration,the leaf area index assumed first increased and then decreased,reached to maxmium in flower bud liver moss time.The value of the leaf area index increased with the earlier sowing date and the higher density,the quantity of fertilizer had little influence to it.Along with the increased quantity of fertilizer,the nitrogen quantity of the organs showed the increasing tendency,the sowing date and the density had no remarkable influence to it; Simultaneously,the quantity of fertilizer had much influence to the quantity of phosphorus,the sowing date and the density were not remarkable to its influence;there was little difference between the quantity of potassium element in the organs in the whole duration,and the three factors had little influence on it.The three factors had oblivious influence on the ftrst effective branch number.the first effective branch number had positive correlation with the yield except the influence of density.The three factors also effected the pod per plant and the density showed much more importance than others.The three factors had no obvilious influence on the seed number per pod,it showed that the seed number per pod was determined by the genetic.The quantity of fertilizer had obvilious influence on 1000-grain weight,but the sowing date and the density didn't had. 4 Through the analysis of the output and the constitution factor correlation and the latus rectum:the number of plants,the angle number of seeds and the weight of a thousand seeds had positive correlation with the output,the relativity size counts(0.570)＞for the angle number of seeds(0.431)＞weight of a thousand seeds(0.084),the single effective silicle number and the output assume the inverse correlation(-0.028).Meanwhile according to the path coefficient,we knowed that if enhancing the output,a number was a quite important aspect,next for angle number of seeds and weight of a thousand seeds.The effective pod per plant had negative correlation with the yield for the influence of density.