【作者】 刘文祥；

【导师】 青先国；

【作者基本信息】 湖南农业大学 ， 生态学， 2013， 博士

【摘要】 水稻是中国重要的粮食作物之一,气候环境的变化对水稻产生了重大影响。因此,明确区域气候变化特点和开展适应气候变化的群体调控技术研究很有必要。本研究分析了长江中游地区50个气象台站近50年的双季早晚稻各生育时期的农业气候资源变化特点,并在此基础上运用不同氮肥水平(NO-施纯氮0kg/hm2; N90-施纯氮90kg/hm2;N135-施纯氮135kg/hm2; N180-施纯氮180kg/hm2; N225-施纯氮225kg/hm2)、密度(D45-每公顷移栽45万穴；D30-每公顷移栽45万穴；D22-每公顷移栽45万穴；D16-每公顷移栽45万穴)和每穴栽插苗数(B1-每穴1粒谷苗；B2-每穴2粒谷苗；B3-每穴3粒谷苗；B4-每穴4粒谷苗)两两组配调控群体,并通过对三种调控措施作用效果的研究,最终形成早晚稻不同群体调控理论和技术体系,为双季早晚稻适应气候变化的高产高效栽培提供理论和技术依托。得到结论如下：1、探明了长江中游地区双季早晚稻各生育时期农业气候资源变化特征该地区早稻生长期内各生育期的平均温度、平均日最高温度、平均日最低温度、大于10℃积温等农业气侯资源均有一定幅度的增加；其中移栽返青分蘖期的平均温度、平均日最高温度、平均日最低温度等增幅最大,平均增温速率分别达1.05℃、1.34℃、0.84℃/10a；大于10℃积温平均增幅最明显的也是移栽返青分蘖期,增温速率为35.48℃/10a,其次是播种育秧期,为26.48℃/10a；移栽返青分蘖期的日照时数表现为增加,其它时期均减少；降水变化趋势除播种育秧期、移栽返青分蘖期下降外,其它时期均略有增加,而生殖生长期降水量的增加不利于灌浆结实。晚稻生长期内温度变化趋势为持续升高,抽穗期的平均温度、平均日最高温度、平均日最低温度的平均增速分别为0.42、0.34、0.57℃/10a,灌浆成熟期的平均温度、平均日最高温度、平均日最低温度的平均增幅分别为0.44、0.48、0.46℃/10a；晚稻播种育秧期、移栽返青分蘖期、孕穗期、抽穗期以及灌浆成熟期的日照时数均下降,其下降速率依次为：-14.86、-31.43、-31.08、-5.16、-7.87/10a；晚稻生长期内降水量除抽穗期和灌浆成熟期为减少外其它时期均增加,其气候倾向率依次为：3.76、21.56、6.76、-5.22、-18.40mm/10a,气候变化对晚稻的不利主要表现在群体构建的关键时期—移栽返青分蘖期和孕穗期的低温、寡照和降水偏多。因此,该区域气候变化对早稻是利大于弊,对晚稻而言则表现为制约其高产潜力的发挥。2、不同密度和栽插苗数调控能提高区域双季早晚稻适应气候变化的能力早稻剑叶光合速率随密度的增加而增加；栽插苗数单因对光合速率的影响表现为：B3>B4>B2；D45B3处理的剑叶光合速率、冠层叶片SPAD值、冠层太阳光截获率均高于其它处理。晚稻剑叶光合速率则随密度的增加而下降,不同栽插苗数处理表现为：B2>B1>B3,密度和在栽插苗数互作以D22B2处理的光合速率最高；晚稻冠层叶片SPAD值随密度、栽插苗数的增加均会降低,群体冠层太阳光截获率以D22B2最高。不同密度和栽插苗数调控对早晚稻产量及其构成因子的影响为：早稻不同密度处理的产量关系为D30>D45>D22,晚稻各密度处理产量依次为D22>D30>D16；早晚稻产量都跟栽插苗数呈单峰曲线关系,早晚稻分别是B3、B2最高。在本试验条件下：早稻在移栽密度33×104穴/hm2的基础上配合每穴3个栽插苗数,晚稻在移栽密度为26×104穴/hm2的基础上搭配每穴1个载插苗数能发挥高产潜力,获得高产。3、氮密调控对区域气候变化下的双季稻群体、产量及其构成因子有明显效果不同氮肥水平的早稻叶面积指数在生长后期N135处理最高,叶面积指数和干物质积累均会随密度增加而增加,栽插密度对早稻冠层截获率的影响表现为D30最高；氮肥用量和密度对早稻穗粒数、结实率影响不大,对有效穗和千粒重影响较大；氮肥和密度互作对有效穗影响达显著水平；施氮水平为135kg/m2时早稻产量最高,其次是施氮量180kg/hm2的处理。晚稻冠层光能截获是N180处理的要高于其他处理；不同密度处理以D22处理最高；不同氮肥水平的剑叶光合速率则以N180处理最高。氮肥对晚稻有效穗和穗粒数影响较大；晚稻有效穗数随栽插密度的增加而增加,但每穗粒数却与之相反；氮肥对晚稻产量的影响以施氮量为180kg/hm2最高；密度水平对产量的影响表现为：D30最高,D16最低,表明产量随密度的增加而增加。在区域气候变化下,双季早稻在密度和施氮量分别为36.60×104穴/hm2和141.20kg/hm2,可获最高为10359.30kg/m2;晚稻在氮肥水平为190.30kg/hm2,移栽密度为23.60×104穴/hm2时,可获得最高产。4、区域气候变化下氮肥和栽插苗数对双季稻有明显调控效果早稻叶面积指数随栽插苗数的增加而增加,孕穗期每穴3个栽插苗数处理的叶面积指数要比2个栽插苗数处理的高0.3；不同氮肥水平在齐穗期以前是N135处理最高,齐穗后N180处理最高；早稻冠层光能截获率随氮肥水平的提高而增加,栽插苗数对冠层光能截获的影响效果为B3>B2。晚稻群体叶面积指数则随氮肥水平的增加而增加；不同栽插苗数处理间的叶面积指数为B2大于B1。早晚稻有效穗均随氮肥水平的增加而增加,但每穗粒数与氮肥水平间却呈单峰曲线关系；氮肥和栽插苗数互作对每穗粒数的影响,早稻为N135B3最高,晚稻则是N180B1最高。本试验结果表明,不同氮肥水平的早稻产量以N135最高,其次是N180；早稻不同栽插苗数处理的产量表现为B3>B2。晚稻产量以N180处理最高,但N135的产量反而比N225的高；每穴1个栽插苗数的产量要大于2个栽插苗数处理的；氮肥和栽插苗数互作则是N180B1的产量最高,NOB1最低。5、提出了适应区域气候变化的双季早晚稻不同群体调控技术体系根据区域双季早晚稻各生育时期气候变化的差异,提出了适应区域气候变化的双季早晚稻不同群体调控技术体系：双季早晚稻的氮肥施用量分别在141.20-145.20、184.70-190.30kg/hm2之间,移栽密度分别为33.40×104-36.60×104、23.60×104-25.80×104穴/hm2之间,早晚稻分别搭配每穴栽插3、1粒谷苗,是高产高效的栽培方式。更多还原

【Abstract】 Rice is one of the important food crops in China, but changes in climate and environment has brought or will bring key effects to the rice production. Thus, it is necessary to identify the characteristics of regional climatic changes and to carry out research on population regulation techniques that are adaptable to climate change. This study analyzes the characteristics of changes in agro-climatic resources at the middle reaches of the Yangtze River, where double-season rice has been developed at various growth stages over the last50years. Based on this analysis, the different nitrogen fertilizer rate (NO-nitrogen application was Okg/ha; N90-nitrogen application was90kg/ha; N135-nitrogen application was135kg/ha; N180-nitrogen application was180kg/ha; N225-nitrogen application was225kg/ha) and transplanting density (D45-transplanting densities of45×104hills/ha; D30-transplanting densities of30×104hhills/ha; D22-transplanting densities of22×104hills/ha; D16-transpl-anting densities of16×104hills/ha) and number seedling of per hill (B1-1seedling per hill. B2-2seedlings per hill, B3-3seedlings per hill, B4-4seedlings per hill) has been employed to regulate populations, and a study on the effects of these three methods is carried out. Finally, the different population regulation theory and technique systems for early and late rice are developed. This will provide theoretical basis and technical guidance for high-efficient planting and high yield of double-season rice under the influence of climate change. The conclusions are as follows:1. Ascertain the agro-climatic resources change characteristics of double crop rice at various growth stages at the middle reaches of the Yangtze RiverThe agro-climatic resources, such as the mean temperature, mean daily maximal temperature and mean daily minimum temperature and>10℃accumulated temperature during early-season rice growth period were significantly increased. The increase speed of the mean temperature, mean daily maximal temperature and mean daily minimum temperature during the transplanting and returning green and to the tilling stage of early-season rice was1.05℃/10a,1.34℃/10a and0.84℃/10a respectively. The>10℃accumulated temperature during the transplanting and returning green stage to the tilling stage of early-season rice was significantly increased, the increase speed was35.48℃/10a, followed by the seeding and seedling-raising stage of early rice, the increase speed was26.48℃/10a. The sunshine hours only during the planting and returning green stage to the tilling stage of early-season rice was increased. The precipitation during the seeding and seedling-raising stage and the planting and returning green stage to the tilling stage of early-season rice were decreased. The increase speed of the mean temperature, mean daily maximal temperature and mean daily minimum temperature during the heading stage and the filling and ripening stage of late-season rice was0.42℃/10a,0.34℃/10a,0.57℃/10a;0.44℃/10a,0.48℃/10a,0.46℃/10a respectively, but the decrease speed of the sunshine hours and the precipitation during the heading stage and the filling and ripening stage of late-season rice was5.16h/10a,5.22mm/10a;7.87h/10a,18.40mm/10a respectively, the climate changed brought the temperature is low and less sunshine and excessive precipitation that had an adverse effect on rice during the transplanting and returning green and to the tilling stage and booting stage. Therefore, the regional climate changed would be beneficial to early rice production, but had a negative effect on the yield potential of late rice.2. The regulation of different transplanting density and number seedlings per hill can improve the adaption to regional climate change ability of double-season riceThe photosynthetic rate of early-season rice flag leaf increased with the increase of transplanting density, the photosynthetic rate of early-season rice flag leaf for different number seedlings per hill were B3>B4>B2. The photosynthetic rate, SPAD values of canopy leaves and canopy solar radiant interception rate of early-season rice for D45B3was the highest. The photosynthetic rate of late-season rice flag leaf decreased with the increase of transplanting density, the photosynthetic rate of late-season rice flag leaf for different number seedlings per hill are B2>B1>B3, the photosynthetic rate of late-season rice flag leaf for2seedlings with the transplanting density of22×104hills/ha (D22B2) was the highest. The number of seedlings per hill and the yield of early-season and late-season rice showed a single peak curve relationship. The yield of early-season rice for different transplanting density were D30>D45>D22, the yield of late-season rice for different transplanting density were D22>D30>D16. The higher would be obtained:33×104hills/ha for the early-season rice with3seedlings per hill and26x104hills/ha for the late-season rice with1seedling per hill.3. The regulation of different nitrogen fertilizer rates and transplanting density has significant effects on population characteristics, yield and its components of double-season rice of regional climate changeThe LAI of nitrogen rate of135kg/ha was the highest during late growth period of early-season rice, the LAI and dry matter accumulation increased with the increase of transplanting density, the solar radiation interception rate of canopy for early-season rice with the transplanting density of30×104hills/ha (D30) was the highest. The effect of nitrogen fertilizer rate on early-season rice grain number per panicle and seed setting rate were lower than that on the number of productive panicles and1000-grain weight. The effect of interaction of nitrogen fertilizer and transplanting density on grain number per panicle was significant. The yield of early-season rice for the nitrogen rate of135kg/hawas the highest, the yield of early-season rice for the nitrogen rate of180kg/ha was the second highest and they were10245.04kg/ha,9962.12kg/ha respectively. Both of the nitrogen rates of180kg/ha and transplanting density of22×104hills/ha (D22) for late-season rice would be obtain the highest solar radiation interception rate of canopy. The photosynthetic rate of late-season rice flag leaf for the nitrogen rate of180kg/ha was the highest during the heading stage and the photosynthetic rate of late-season rice flag leaf for transplanting density of22×104hills/ha was the highest. The canopy solar radiant interception rate of late-season rice for N180D16was the highest during the heading stage and during the milky stage N225D16was the highest. The nitrogen fertilizer rates had more effect on the late-season rice grain number per panicle and number of productive panicles, the number of productive panicles increased with the increase of transplanting density, but the grain number per panicle decreased with the increase of transplanting density. The late-season rice with the nitrogen rate of180kg/ha could get the maximum yield, the transplanting density had less effect on the yield of late-season rice, but the yield increased with the increase of transplanting density. In order to obtain the higher yield, the nitrogen rate and transplanting density were recommended as:N141.20kg/ha for the early-season rice with the transplanting density of36.60×104hills/ha and N190.30kg/ha for the late-season rice with the transplanting density of23.60×104hills/ha.4. The regulation of different nitrogen fertilizer rates and number seedlings per hill has significant effects on double-season rice of regional climate changeThe LAI of early-season rice increased with the increase of number seedlings per hill, in the booting stage the LAI of early-season rice increased0.3for3seedlings per hill in comparison with that under the condition of2seedlings per hill. Before the heading stage the LAI of early-season rice for the nitrogen rate of135kg/ha was the highest, but after the heading stage the nitrogen rate of180kg/ha was the highest. The solar radiation interception rate of canopy of early-season rice increased with the increase of nitrogen fertilizer rates, the solar radiation interception rate of canopy of early-season rice for different number seedlings per hill were B3>B2. The LAI of late-season rice increased with the increase of nitrogen fertilizer rates, the LAI of late-season rice for different number seedlings per hill were B2> B1.The number of productive panicles of early-season and late-season rice increased with the increase of nitrogen fertilizer rates, nitrogen fertilizer rates and the grain number per panicle showed a single peak curve relationship for early and late rice, The effects of different nitrogen fertilizer rates and number seedlings per hill on the grain number per panicle showed that both of the N135B3for early-season rice and N180B1for late-season rice were the highest. The yield of nitrogen rate of135kg/ha of early-season rice was the highest and nitrogen rate of180kg/ha was the second highest. The yield of early-season rice of3seedlings per hill was higher than that of2seedlings per hill. The yield of nitrogen rate of180kg/ha of late-season rice was the highest, but the yield of nitrogen rate of135kg/ha was higher than that of nitrogen rate of225kg/ha, the yield of lseeding per hill more than that of2seedlings per hill. The yield of nitrogen rate of180kg/ha for late-season rice of1seeding per hill was the highest and nitrogen rate of Okg/ha for late-season rice of1seeding per hill was the lowest.5. The population regulation theory and technique system will provide for adaptation to regional climate change of double-season riceAccording to the different climate change for double-seasons rice at each growth stages and take the high yield and high economic efficiency into consideration, the N fertilization rate, transplanting density and number seedlings per hill were recommended as:N141.20-145.20kg/ha for early-season rice with the transplanting density of33.40-36.60×104hills/ha of3seedlings per hill and N184.70-190.30kg/ha for late-season rice with the transplanting density of23.60-25.80×104hills/ha of lseeding per hill.更多还原