双季稻不同栽培模式的辐射利用与氮肥利用效率研究
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摘要
粮食安全和节肥减排是我国作物生产当前面临的两大重要任务,实现高产与肥水高效利用成为我国水稻生产的迫切需求。为了研究水稻产量形成和氮肥利用效率的变化规律,于2009年在浏阳市永安镇大田条件下以移栽和摆栽两种栽插方式进行了早、晚双季试验,设置不施N肥空白处理(T1)和当地农民习惯栽培(T2)、高产高效栽培(T3)、超高产栽培(T4)及高效超高产栽培(T5)等四个栽培模式,通过构建不同产量和N肥效率平台,同步分析了不同产量条件下双季稻的冠层辐射利用特性和氮肥利用效率,以期为建立水稻产量与养分资源利用效率协同提高的技术途径提供基础理论和实践依据。主要研究结果如下：
(1)T3、T4、T5的稻谷产量早、晚季均显著高于农民习惯栽培模式T2，移栽方式的产量呈现T4>T5>T3>T2梯度变化,定距摆栽方式则呈现T4>T3>T5>T2梯度变化。其中T4产量最高,早、晚两季的平均产量在移栽和摆栽条件下分别达到8.62t／ha和9.24t／ha,比农民习惯栽培T2分别提高30%和26%,差异达显著水平。表明通过栽培和养分管理措施的集成优化,可以大幅度提高双季稻的产量。
(2)水稻冠层太阳辐射截获量和辐射利用率(RUE)在处理间存在显著差异并与产量密切相关。冠层辐射截获量在早、晚两季及移栽、定距摆栽两种栽插方式中均表现为T4>T5>T3>T2,其中T4显著高于T2；RUE在移栽方式下不同栽培模式间变化在1.39-1.54g／MJ(早季)和1.20-1.52g／MJ(晚季),在定距摆栽方式下变化在1.43～1.68g／MJ(早季)和1.39-1.70g／MJ(晚季),其中T3、T4的RUE在两季均显著高于T2,T5在晚季也显著高于T2。表明显著增加水稻群体的辐射截获量和辐射利用率,是双季稻不同栽培模式比农民模式显著增产的重要生理基础。
(3)群体分蘖、叶面积指数、地上部干物质的积累、生长速率等群体生长特征在各栽培模式间存在差异,高产高效栽培、超高产栽培和高效超高产栽培的成穗率、最大叶面积指数和成熟期干物质积累均比农民习惯栽培显著提高。
(4)T3、T4、T5的氮肥吸收利用率(RE)、农学利用率(AE)和氮肥偏生产力(PFP)早、晚季均显著高于T2。除移栽晚稻外,T5的RE和AE表现最大,分别达到38.1(早季)～40.8%(晚季)和30.8(早季)～20.5 kg／kg(晚季)。PFP均为T3>T5>T4>T2,T3两季平均值为62.0kg／kg,显著高于其他栽培模式。说明在相同的基础地力条件下,通过栽培和养分管理措施的集成优化,能显著提高双季稻的氮肥利用效率。
To ensure Food security and to reduce fertilizer rates for alleviating environment pollution are two key tasks in crop production in our country. Therefore it is urgent to achieve higher yield and higher use efficiency of resources in rice production in China. Early rice and late rice field experiments were conducted in Yong'an Town, Liuyang City in 2009 to investigate the mechanisms of high yield formation and high nitrogen use efficiency(NUE). Treatments included nitrogen omission plot (T1), local farmer's practice model(T2), high yield and high NUE model(T3), super-high yield model(T4), and super-high yield with high NUE model(T5). The cultivation models were respected to establish different yield and different NUE platforms. We analyzed the characteristics of canopy radiation utilization and NUE under different yield conditions.The major findings are as follows:
(1) Rice yield of treatment T3、T4、T5 are significantly higher than that of treatment T2. The yield presented as T4>T5>T3>T2 and T4>T3>T5>T2 at transplanting and dibble-planting, respectively. T4 produced the highest yield of 8.62 t/ha and 9.24 t/ha, which were 30% and 26% higher over T2 in early rice and later rice, respectively. The difference was significant. It showed that the yield of double season rice could be increased differently by integrating and optimizing of cultivation technology and nutrient management approaches.
(2) Significant differences in the amount of intercepted solar radiation (ISRA) and the radiation use efficiency (RUE) existed among tested treatments, and were closely related to rice yield. ISRA presented as T4>T5>T3>T2 in the experiments. RUE value at transplanting were 1.39-1.54g/MJ in early rice and 1.20-1.52g/MJ in late rice, while at dibble-planting were 1.43-1.68g/MJ in early rice and 1.39-1.70g/MJ in late rice. RUE in T3 and T4 are all significantly higher than that in R2. The result indicates that ISRA and RUE enhancement is the physiological foundation of rice yield increasing in different cultivation models in double season rice production.
(3) There exist differences in the rice population growth characters such as tillering dynamics, leaf area index(LAI), dry matter accumulation and crop growth rate(CGR) among different cultivation models. T3, T4, and T5 had significantly higher effective tiller rate, dry matter accumulation, maximum LAI than T2.
(4) Nitrogen recovery efficiency(RE), nitrogen agronomy efficiency(AE) and nitrogen partial factor productivity(PFP) were significant higher in T3,T4,and T5 than in T2 across two seasons and two transplanting types. T5 had the highest RE and AE except in transplanting type in later season, averaged from 38.1% and 30.8kg/kg in early rice, and 40.8% and 20.5kg/kg in later season across two transplanting types, respectively. Stable trend was observed for PFP in different cultivation models, i.e., T3>T5>T4>T2. PFP in T3 averaged 62.0 kg/kg, significantly higher than in any other cultivation models across two seasons and two transplanting types. Therefore, NUE in double season rice could also be significantly increased by integrating and optimizing of cultivation technology and nutrient management approaches under the same soil fertility condition.
(1)T3、T4、T5的稻谷产量早、晚季均显著高于农民习惯栽培模式T2，移栽方式的产量呈现T4>T5>T3>T2梯度变化,定距摆栽方式则呈现T4>T3>T5>T2梯度变化。其中T4产量最高,早、晚两季的平均产量在移栽和摆栽条件下分别达到8.62t／ha和9.24t／ha,比农民习惯栽培T2分别提高30%和26%,差异达显著水平。表明通过栽培和养分管理措施的集成优化,可以大幅度提高双季稻的产量。
(2)水稻冠层太阳辐射截获量和辐射利用率(RUE)在处理间存在显著差异并与产量密切相关。冠层辐射截获量在早、晚两季及移栽、定距摆栽两种栽插方式中均表现为T4>T5>T3>T2,其中T4显著高于T2；RUE在移栽方式下不同栽培模式间变化在1.39-1.54g／MJ(早季)和1.20-1.52g／MJ(晚季),在定距摆栽方式下变化在1.43～1.68g／MJ(早季)和1.39-1.70g／MJ(晚季),其中T3、T4的RUE在两季均显著高于T2,T5在晚季也显著高于T2。表明显著增加水稻群体的辐射截获量和辐射利用率,是双季稻不同栽培模式比农民模式显著增产的重要生理基础。
(3)群体分蘖、叶面积指数、地上部干物质的积累、生长速率等群体生长特征在各栽培模式间存在差异,高产高效栽培、超高产栽培和高效超高产栽培的成穗率、最大叶面积指数和成熟期干物质积累均比农民习惯栽培显著提高。
(4)T3、T4、T5的氮肥吸收利用率(RE)、农学利用率(AE)和氮肥偏生产力(PFP)早、晚季均显著高于T2。除移栽晚稻外,T5的RE和AE表现最大,分别达到38.1(早季)～40.8%(晚季)和30.8(早季)～20.5 kg／kg(晚季)。PFP均为T3>T5>T4>T2,T3两季平均值为62.0kg／kg,显著高于其他栽培模式。说明在相同的基础地力条件下,通过栽培和养分管理措施的集成优化,能显著提高双季稻的氮肥利用效率。
To ensure Food security and to reduce fertilizer rates for alleviating environment pollution are two key tasks in crop production in our country. Therefore it is urgent to achieve higher yield and higher use efficiency of resources in rice production in China. Early rice and late rice field experiments were conducted in Yong'an Town, Liuyang City in 2009 to investigate the mechanisms of high yield formation and high nitrogen use efficiency(NUE). Treatments included nitrogen omission plot (T1), local farmer's practice model(T2), high yield and high NUE model(T3), super-high yield model(T4), and super-high yield with high NUE model(T5). The cultivation models were respected to establish different yield and different NUE platforms. We analyzed the characteristics of canopy radiation utilization and NUE under different yield conditions.The major findings are as follows:
(1) Rice yield of treatment T3、T4、T5 are significantly higher than that of treatment T2. The yield presented as T4>T5>T3>T2 and T4>T3>T5>T2 at transplanting and dibble-planting, respectively. T4 produced the highest yield of 8.62 t/ha and 9.24 t/ha, which were 30% and 26% higher over T2 in early rice and later rice, respectively. The difference was significant. It showed that the yield of double season rice could be increased differently by integrating and optimizing of cultivation technology and nutrient management approaches.
(2) Significant differences in the amount of intercepted solar radiation (ISRA) and the radiation use efficiency (RUE) existed among tested treatments, and were closely related to rice yield. ISRA presented as T4>T5>T3>T2 in the experiments. RUE value at transplanting were 1.39-1.54g/MJ in early rice and 1.20-1.52g/MJ in late rice, while at dibble-planting were 1.43-1.68g/MJ in early rice and 1.39-1.70g/MJ in late rice. RUE in T3 and T4 are all significantly higher than that in R2. The result indicates that ISRA and RUE enhancement is the physiological foundation of rice yield increasing in different cultivation models in double season rice production.
(3) There exist differences in the rice population growth characters such as tillering dynamics, leaf area index(LAI), dry matter accumulation and crop growth rate(CGR) among different cultivation models. T3, T4, and T5 had significantly higher effective tiller rate, dry matter accumulation, maximum LAI than T2.
(4) Nitrogen recovery efficiency(RE), nitrogen agronomy efficiency(AE) and nitrogen partial factor productivity(PFP) were significant higher in T3,T4,and T5 than in T2 across two seasons and two transplanting types. T5 had the highest RE and AE except in transplanting type in later season, averaged from 38.1% and 30.8kg/kg in early rice, and 40.8% and 20.5kg/kg in later season across two transplanting types, respectively. Stable trend was observed for PFP in different cultivation models, i.e., T3>T5>T4>T2. PFP in T3 averaged 62.0 kg/kg, significantly higher than in any other cultivation models across two seasons and two transplanting types. Therefore, NUE in double season rice could also be significantly increased by integrating and optimizing of cultivation technology and nutrient management approaches under the same soil fertility condition.
引文
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[3]彭少兵,黄见良,钟旭华等.提高中国稻田氮肥利用率的研究策略[J].中国农业科学,2002,35(9)：1095-1103.
[4]徐明岗,孙小风,邹长明等.稻田控释氮肥的施用效果与合理施用技术[J].植物营养与肥料学报,2005,11(4)：487-493.
[5]Ohnishi M, Horie T, Homma K,el at.Nitrogen management and cuhivar efects on rice yield and nitrogen use eficiency in Northeast Thailand[J].Field Crop Res,1999, 64:109-120.
[6]李庆逵.中国农业持续发展中的肥料问题.江西：江西科学技术出版社.1997.
[7]李荣刚.高产农田氮索肥效与调控途径—以江苏太湖地区稻麦两熟农区为例推及全省.北京：中国农业大学博士学位论文.2000.
[8]林葆.提高作物产量,增加施肥效应.见：中国土壤学会.中国土壤科学的现状与前景,江苏：江苏科学技术出版社,1991：29-36.
[9]De Datta S K.Improving nitrogen fertilizer efficiency in lowland rice in tropical Asia[J]. Fert Res.1986(9):171-186.
[10]张绍林,朱兆良,徐银华等.关于太湖地区稻麦上氮肥的适宜用量[J].土壤,1988,20：5-9.
[11]Cassman,K.G.,Peng,S.,Olk D.C et al.Opportunities for increased nitrogen use efficiency from improved resource management in irrigated rice systems[J]. Field Crops Res,1998,56:7-38.
[12]Vlek,P.L.G.,Byrnes,B.H.The efficacy and loss of fertilizer N in low land rice [J].Fert Res.,1986,9:131-147.
[13]De Datta,S.K.;Buresh,R.J.1989.Integrated nitrogen management in irrigated rice [J].Adv.Soil Sci,10:143-169.
[14]朱兆良.关于提高氮肥利用率问题.见：林葆,李家康主编,肥料与农业发展,国际学术讨论会论文集,1999：221-229.
[15]朱兆良.稻田节氮的水肥综合管理技术的研究[J].土壤,1991,23(5)：241-245.
[16]贺帆,黄见良,崔克辉等.实时实地氮肥管理对不同杂交水稻氮肥利用率的影响[J].中国农业科学,2008,41(2)：470-479.
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