导　　师： 周广生

学科专业： 090101

授予学位： 硕士

作　　者： ;

机构地区： 华中农业大学

摘　　要： 近年来我国油菜生产面临的困境是：一是目前我国油菜生产仍然以人工作业为主,用工量大,劳动强度高,劳动生产率低,导致生产成本高,比较效益差。据测算,在油菜生产成本中劳动力成本占60-70/%,一亩地耗工12-15个左右,劳动力成本240-300元,据试验表明,在我国采用油菜直播栽培模式,每亩可比传统的育苗移栽栽培模式减少用工2-3个；二是前茬作物收获期不一,导致后茬油菜播种期发生相应改变,目前长江流域不同田块的油菜播种期在可从9月中下旬开始,一直持续到10月中下旬,前后相差达30天以上。三是农户仍按照常规的育苗移栽栽培模式的氮肥运筹进行田间氮肥管理,尚未建立与不同播期相适应的直播油菜的氮肥运筹模式,导致氮肥用量偏高,效益下降,环境污染隐患增加。针对这些情况,本试验以华双五号为试验材料,通过大田试验研究不同播期,不同施氮水平及不同氮肥基追比处理对油菜生长发育、干物质积累进程、产量、品质及经济性状的影响,期望找到不同播期条件下,直播油菜氮肥适宜基追比及其产量等性状的形成机理,为直播油菜高产高效栽培提供技术及理论支持。本研究结果表明： 1.播期、氮肥及氮肥基追比对油菜发育进程的影响 不同播期、施氮量、氮肥基追比均会对油菜生长生育期进程产生影响。其中,播期因素对油菜发育的影响极显著,随播期推迟,出苗时间延长,越冬期植株矮小,最大叶长、最大叶宽、绿叶数、总叶数、叶面积指数、根颈粗、干物质重均有下降。具体表现为：与9月15日播种的油菜相比,10月25日播种的油菜4个生育期各指标的检测值明显下降,苗高降低51.2/%-80.22/%,绿叶数减少2-8片,总叶片数减少2.17-5.09片,叶面积指数LAI下降23/%-57.2/%,根颈粗下降18.9/%-45.32/%,干物质重量下降4/%-16.48/%。油菜始花至成熟期缩短,全生育期缩短,播期9月15日、10月5日与10月25日播种至出苗时间分别为5、8、12天,始花至成熟期时间为72、69.3、64.3天。 氮肥对油菜各生育期的生长影响也较为显著,但对油菜苗期生长影响最大。本试验中,在相同播期条件下设置的三水平氮肥施入量12kg//667m2、18kg//667m2、24kg//667m2/)处理表明,12kg//667m2/(供氮不足/)油菜冬至苗株高、绿叶数、总叶数、叶面积指数、地上和地下部分干重检测值均低于18kg//667m2和24kg//667m2的施肥处理,18kg//667m2的施肥处理次之。 氮肥基追比对直播油菜各生育期的生长也有显著影响,在发育各阶段间大体呈现为播期越早,基肥与追肥比例小的苗发育进程长势较好,反之较差。播期晚,氮肥基追比小,基肥供应不足导致苗长势较差,反之基追比大处理条件下的植株较其他晚播植株在施入较多底肥之后长势较为迅速为生长发育奠定基础。 2.播期、氮肥及氮肥基追比对油菜产量的影响 播期对油菜产量的影响最为显著,油菜产量随播期的提前呈现出增长态势,9月15日播种,产量最高,达507.20g//m2；最迟播期10月25日产量为212.09g//m2,差距达2倍以上。随播种期推迟,油菜的株高、根茎粗、单株干物质重、有效角果数、每角果粒数、千粒重等显著降低。数据分析表明：与9月15日播期油菜相比,10月25日播期下的油菜,株高降低8.79/%-26.36/%、主花序长降低11.32/%-35.97/%、一次分枝减少13.3/%-21.57/%、有效角果数降低23.34-46.63/%、单株产量降低24.67-69.62/%、千粒重降低13.89-38.53/%。 产量随着施氮水平增加呈现出先增后减的趋势,在18kg//667m2氮肥处理下油菜一次分枝、二次分枝、单株角果数、单株产量、千粒重均显著增加并且产量达到最大值。在12kg//667m2处理下产量最低,24kg//667m2处理次之。 本试验中基追比对油菜产量影响的规律可以概括为：播期提前、基追比小,收获产量较高；播期滞后、基追比大,收获产量较高；正常播期、基追比大,收获产量较高。 3.播期、氮肥及氮肥基追比对油菜品质的影响 不同播期处理下油菜籽各成分差异较大。播期推迟油菜籽蛋白质含量趋增,含油量趋于减少,9月15日播种蛋白含量较10月25日高1.2/%-19.83/%,含油量较之低10.45/%-31.93/%,芥酸含量和亚麻酸含量均随播期推迟而降低,亚油酸含量随播期推迟明显升高,晚播获产的油菜籽中硫甙成分含量高,早播或晚播获产的菜籽中油酸含量均比正常播期高。相同播期条件下,籽粒蛋白质含量随氮肥增加而升高,含油量则随之降低。 In recent years, the dilemma of China's rapeseed production are as follows:First, the current rapeseed production in China is still manual work-based, labor large amount of high labor intensity, low labor productivity, leading to high production costs, relatively poor efficiency. It is estimated that in rape production costs, labor costs accounted for60to70percent of an acre of land consuming work about12to15, labor costs240-300RMB. According to the tests showed that in China uses the rape direct seeding cultivation pattern in our country, compared to the tradition transplants the cultivation pattern reduction to employ labor2-3for seedling transplanting in per acre. Second, different former crop harvest time resulting in the next crop planting season a corresponding change, current rape sowing time of the different fields in the Yangtze River basin from late September start, lasted until the end of October, up to30days before and after above. Third, farmers still follow conventional transplanting cultivation model of nitrogen fertilizer in field management, has not been commensurate with the sowing of direct seeding oilseed rape nitrogen application patterns, leading to high nitrogen, benefits decline, pollution risks increase. In response to these problems, Huashuang No.5is used for testing materials in this article, through field trials to study on different sowing date, different levels of nitrogen and nitrogen dressing ratios on growth of rape, process of dry matter accumulation, yield, quality and economic characters of rapeseed, pursuing to the change rule and forms mechanism of rapeseed for better cultivation performance. Research results show that: 1. Different sowing date and different ratios of base and topdressing of nitrogen levels effects on growth and development of the rape: Firstly, Sowing date, nitrogen rate and its ratio of base and topdressing are all have an impact on the whole growth stages. Among them, sowing date has the greatest impact of all, as we put off the sowing date, the Seedling emergence stage delayed, the index of rapeseed such as the plants height, the maximum of leaf length and width, green leaves number, total leaf number, leaf area index, the root neck width, the ground and underground dry weight are all decreased over through wintering stage, concrete manifestation as follows:Compared with the sowing day of Sept.15, Oct.25sowing rape index declined significantly in four growth stages, the plants reduced51.2/%-80.22/%high, the green leaf number reduced2-8piece, the total number of leaves reduced2.17-5.09piece, leaf area index fell23/%-57.2/%,root neck crude fell18.9/%-45.32/%,dry matter weight reduced4/%-16.48/%,the beginning flower to the mature period shorted, For broadcast on15Sept.5, Oct.5, Oct.25, from sowing seeds to the emerging,time respectively needs5,8,12d,and flowering to maturity time costs72,69.3,64.3d. The nitrogenous fertilizer is remarkable to the rape growth period, but the biggest impact for t under the conditions set nitrogen fertilizer application rates in3level /(12kg//667m2,18kg//667m2,24kg//667m2/) of12kg//667m2nitrogen deficiencies /(for nitrogen insufficient/) the height of plants, green leaves number, total leaf number, leaf area index, above and below ground dry weight detection value lower than18kg//667m2and24kg//667m2nitrogenous supplement,18kg//667m2nitrogenous supplement followed by. Different ratio of base and topdressing of nitrogen takes significant impact on the growth of rapeseed. In the stages of development generally showing that:the earlier the sowing date, and the bigger ratio of base and topdressing of nitrogen supplement the better processes are under growing, otherwise bad. Late sowing time and ratio of base and topdressing small,because lack of basic fertilizer supply will resulting in poor seedling growing, Conversely the big ratio of nitrogen, because of large nitrogen supplement will growing more quickly to promoting the growth of rapeseed than other late sowing plants. 2. Different sowing date and different ratios of base and topdressing of nitrogen levels effects on yield of rapeseed: Sowing date on yield of rapeseed is the most significant, showing a growth yield of rapeseed in advance with the sowing date, on sowing date of September15will get the highest yield, up to507.20g//667m2, and compared to the latest broadcast of Oct.25the gap up to212.09g//667m2, more double of the yield. With the sowing date postponed, the rapeseed plant height, coarse roots, dry weight per plant, effective pod number, number per pod,1000-grain weight had a significant reduction. The experimental data were as follows:compared with the rapeseed sowed on Sept.15, rape sowed on October25plants height reduced by8.79/%-26.36/%,11.32/%-35.97/%reduction of the main inflorescence length, once branches had a decrease of13.3/%-21.57/%, the effective number of pods decreased by23.34/%-46.63/%,24.67/%-69.62/%reduction of yield per plant, grain weight decreased by13.89/%-38.53/%. After increase nitrogen offered levels, the yield come to increase and will get the highest yield when Nitrogen reach to18kg//667m2. too much or too little of nitrogen are all makes rape failure, in this test, compared to the others, the nitrogen fertilizer application rates of12kg//667m2will get the lowest output of yield, with the increase of nitrogen provided primary branches, secondary branches, pods per plant, yield per plant, grain weight was significantly increased, but when the fertilizer had amounted to24kg//667m2except the grain weight other indicators are all decreased. In this study, ratios of base and topdressing of nitrogen levels catch up with production relations are as follows:time early, small dressing ratios, harvest yields higher; delayed sowing, large dressing ratios, harvest yields higher; normal planting period and dressing ratios, harvest yields higher. Due to broadcast period ahead of, seedlings in winter period will lack of nitrogen and effect of rapeseed growth and yield formation in the next years. 3. Different sowing dates effect on the quality of rape: Components under different sowing rapeseed larger differences. Defer sowing rapeseed protein content increased oil content tends to decrease, compare to the sowing date, Sept.15seed content of1.2/%-19.83/%protein higher than Oct.25and its oil content lower10.45/%-31.93/%than Oct.25. Content of erucic acid and linolenic acid content are reduced as sowing date postponed. linoleic acid content was significantly higher with the sowing date postponed, glucosinolate composition of rapeseed in high levels on late sowing date, oil acid content of rapeseed on early or late sowing dates than are much higher normal sowing. Under the conditions of the same sowing date, grain protein content increase with nitrogen increased the oil content decreases.

关 键 词： 油菜 播期 施氮量 基追比 产量

分 类 号： [S565.4]

领　　域： [农业科学]