The Taihu Region in eastern China is one of China's most intensive agricultural regions and also one of the economically most developed areas. High nitrogen balance surpluses in the summer rice-winter wheat double...The Taihu Region in eastern China is one of China's most intensive agricultural regions and also one of the economically most developed areas. High nitrogen balance surpluses in the summer rice-winter wheat double-cropping systems are leading to large-scale non-point source pollution of aquifers. In an interdisciplinary approach, four-year (1995-1998) field trials were carried out in two representative areas (Jurong County and Wuxi City) of the Taihu Region. Five farmers' field sites were chosen in each of the 2 locations, with each site divided into 'standard' (farmers' practice) and 'reduced' (by 30%-40%) N fertilization. For both fertilization intensities, N balance surpluses and monetary returns from grain sales minus fertilizer expenditures were calculated in an economic assessment. Based on the field trials, the mineral N fertilizer application rates reduced by about 10% for rice and 20%-30% for wheat were recommended in 1999. Since 1999, the research focused on the trends in N fertilizer application rates and changes in grain and agricultural commodities prices.Summer rice N fertilizer use, in Wuxi City as of 2001, dropped by roughly 25%, while for winter wheat it decreased by 10%-20%, compared to the 1995-1998 period. This has been achieved not only by grain policy and price changes, but also by an increased environmental awareness from government officials. Nitrogen balance surpluses in Anzhen Town (of Wuxi City) have consequently diminished by 50%-75% in rice and by up to 40% in wheat, with reductions being achieved without concomitant decreases in physical grain yields or returns from sales minus fertilizer costs.展开更多
为探究孕穗期冷水灌溉下粳稻籽粒灌浆过程中的干物质、氮素形成积累规律及氮代谢关键酶调控效应，以东农428和松粳10为材料，设置6个冷水灌溉持续时间（0、3、6、9、12和15 d），分析孕穗期冷水灌溉对寒地粳稻籽粒灌浆过程中的干物质、...为探究孕穗期冷水灌溉下粳稻籽粒灌浆过程中的干物质、氮素形成积累规律及氮代谢关键酶调控效应，以东农428和松粳10为材料，设置6个冷水灌溉持续时间（0、3、6、9、12和15 d），分析孕穗期冷水灌溉对寒地粳稻籽粒灌浆过程中的干物质、氮素积累及氮代谢关键酶活性的影响。结果表明，与对照相比，孕穗期冷水灌溉下，寒地粳稻产量及籽粒干物质积累量的变化规律一致，冷水灌溉持续时间越长，产量及籽粒干物质积累量降幅越大。冷水灌溉下，寒地粳稻籽粒干物质积累量降低，除与籽粒干物质最大相对积累速率降低有关外，还与结实率降低、有效穗数和每穗总粒数减少有关。冷水灌溉可提高寒地粳稻籽粒全氮、蛋白氮、成熟期籽粒粗蛋白含量及灌浆前期籽粒谷氨酰胺合成酶（GS）活性。冷水灌溉6 d 可显著提高籽粒谷草转氨酶（GOT）及谷丙转氨酶（GPT）活性，冷水灌溉9~15 d 可显著降低其活性。短期冷水灌溉下（3~6 d），寒地粳稻通过增强有机氮同化过程，促进蛋白质合成，使籽粒氮素含量增加；长期冷水灌溉下（9~15 d），籽粒有机氮同化过程受到抑制，影响氨基酸和蛋白质的合成，最终导致籽粒氮素增幅下降。籽粒全氮、蛋白氮和淀粉颗粒态结合蛋白是不同耐冷性品种响应冷水胁迫的差异产物，其含量可作为耐冷性鉴定的指标。展开更多
【目的】通过水稻幼苗期耐盐性的比较,为寒地水稻耐盐资源筛选及育种提供参考。【方法】以123份苗期耐盐碱粳稻品种(系)为试验材料,以蒸馏水为对照,进行苗期150 mmol/L Na Cl处理,测量其芽长、根长和根数等指标,并对比分析各指标相对抑...【目的】通过水稻幼苗期耐盐性的比较,为寒地水稻耐盐资源筛选及育种提供参考。【方法】以123份苗期耐盐碱粳稻品种(系)为试验材料,以蒸馏水为对照,进行苗期150 mmol/L Na Cl处理,测量其芽长、根长和根数等指标,并对比分析各指标相对抑制率。【结果】盐胁迫下水稻幼苗芽长、根长与根数均极显著下降(P<0.01,下同),相对抑制率表现为根长>芽长>根数。参试材料可分为强耐盐类型、中耐盐类型和弱耐盐类型,其中强耐盐类型芽长和根数抑制率极显著低于中耐盐和弱耐盐类型,而根长抑制率与其他类型无显著差异(P>0.05)。强耐盐材料中品系13G143芽长、根长和根数相对抑制率较低,分别为11.89%、25.36%和10.08%,均低于对照长白9号。【结论】150mmol/L Na Cl胁迫下,水稻品系13G143耐盐碱能力较强,可作为水稻幼苗期耐盐亲本材料应用。展开更多
Water regime and nitrogen（N） fertilizer are two important factors impacting greenhouse gases（GHG） emission from paddy field, whereas their effects have not been well studied in cold region. In this study, we condu...Water regime and nitrogen（N） fertilizer are two important factors impacting greenhouse gases（GHG） emission from paddy field, whereas their effects have not been well studied in cold region. In this study, we conducted a two-year field experiment to study the impacts of water regime and N fertilizer on rice yields and GHG emissions in Harbin, China, a cold region located in high latitudes. Our results showed that intermittent irrigation significantly decreased methane（CH4） emission compared with continuous flooding, however,the decrement was far lower than the global average level. The N2O emissions were very small when flooded but peaked at the beginning of the disappearance of floodwater. The N fertilizer treatments increased CH4 emissions at low level（75 kg N/ha）. But both CH4 and N2O emissions were uninfluenced at the levels of 150 kg N/ha and 225 kg N/ha. Rice yields increased under intermittent irrigation and were highest at the level of 150 kg N/ha. From our results, we recommended that the intermittent irrigation and 150 kg N/ha as the ideal water regime-nitrogen fertilizer incorporation for this area to achieve low GHG emissions without impacting rice yields.展开更多
Ammonia volatilization loss and ^15N balance were studied in a rice field at three different stages after urea application in Taihu Lake area with a micrometeorological technique. Factors such as climate and the NH4^...Ammonia volatilization loss and ^15N balance were studied in a rice field at three different stages after urea application in Taihu Lake area with a micrometeorological technique. Factors such as climate and the NH4^＋-N concentration in the field floodwater affecting ammonia loss were also investigated. Results show that the ammonia loss by volatilization accounted for 18.6%-38.7% of urea applied at different stages, the greatest loss took place when urea was applied at the tillering stage, the smallest at the ear bearing stage, and the intermediate loss at the basal stage. The greatest loss took place within 7 d following the fertilizer application. Ammonia volatilization losses at three fertilization stages were significantly correlated with the ammonium concentration in the field floodwater after the fertilizer was applied. ^15N balance experiment indicated that the use efficiency of urea by rice plants ranged between 24.4% and 28.1%. At the early stage of rice growth, the fertilizer nitrogen use efficiency was rather low, only about 12%. The total amount of nitrogen lost from different fertilization stages in the rice field was 44.1%-54.4%, and the ammonia volatilization loss was 25.4%-33.3%. Reducing ammonia loss is an important treatment for improving N use efficiency.展开更多
基金Project supported by the Volkswagen-Foundation, Germany (No. Ⅱ/69 948) the Institute of Soil Science, Chinese Academy of Sciences.
文摘The Taihu Region in eastern China is one of China's most intensive agricultural regions and also one of the economically most developed areas. High nitrogen balance surpluses in the summer rice-winter wheat double-cropping systems are leading to large-scale non-point source pollution of aquifers. In an interdisciplinary approach, four-year (1995-1998) field trials were carried out in two representative areas (Jurong County and Wuxi City) of the Taihu Region. Five farmers' field sites were chosen in each of the 2 locations, with each site divided into 'standard' (farmers' practice) and 'reduced' (by 30%-40%) N fertilization. For both fertilization intensities, N balance surpluses and monetary returns from grain sales minus fertilizer expenditures were calculated in an economic assessment. Based on the field trials, the mineral N fertilizer application rates reduced by about 10% for rice and 20%-30% for wheat were recommended in 1999. Since 1999, the research focused on the trends in N fertilizer application rates and changes in grain and agricultural commodities prices.Summer rice N fertilizer use, in Wuxi City as of 2001, dropped by roughly 25%, while for winter wheat it decreased by 10%-20%, compared to the 1995-1998 period. This has been achieved not only by grain policy and price changes, but also by an increased environmental awareness from government officials. Nitrogen balance surpluses in Anzhen Town (of Wuxi City) have consequently diminished by 50%-75% in rice and by up to 40% in wheat, with reductions being achieved without concomitant decreases in physical grain yields or returns from sales minus fertilizer costs.
文摘为探究孕穗期冷水灌溉下粳稻籽粒灌浆过程中的干物质、氮素形成积累规律及氮代谢关键酶调控效应，以东农428和松粳10为材料，设置6个冷水灌溉持续时间（0、3、6、9、12和15 d），分析孕穗期冷水灌溉对寒地粳稻籽粒灌浆过程中的干物质、氮素积累及氮代谢关键酶活性的影响。结果表明，与对照相比，孕穗期冷水灌溉下，寒地粳稻产量及籽粒干物质积累量的变化规律一致，冷水灌溉持续时间越长，产量及籽粒干物质积累量降幅越大。冷水灌溉下，寒地粳稻籽粒干物质积累量降低，除与籽粒干物质最大相对积累速率降低有关外，还与结实率降低、有效穗数和每穗总粒数减少有关。冷水灌溉可提高寒地粳稻籽粒全氮、蛋白氮、成熟期籽粒粗蛋白含量及灌浆前期籽粒谷氨酰胺合成酶（GS）活性。冷水灌溉6 d 可显著提高籽粒谷草转氨酶（GOT）及谷丙转氨酶（GPT）活性，冷水灌溉9~15 d 可显著降低其活性。短期冷水灌溉下（3~6 d），寒地粳稻通过增强有机氮同化过程，促进蛋白质合成，使籽粒氮素含量增加；长期冷水灌溉下（9~15 d），籽粒有机氮同化过程受到抑制，影响氨基酸和蛋白质的合成，最终导致籽粒氮素增幅下降。籽粒全氮、蛋白氮和淀粉颗粒态结合蛋白是不同耐冷性品种响应冷水胁迫的差异产物，其含量可作为耐冷性鉴定的指标。
文摘【目的】通过水稻幼苗期耐盐性的比较,为寒地水稻耐盐资源筛选及育种提供参考。【方法】以123份苗期耐盐碱粳稻品种(系)为试验材料,以蒸馏水为对照,进行苗期150 mmol/L Na Cl处理,测量其芽长、根长和根数等指标,并对比分析各指标相对抑制率。【结果】盐胁迫下水稻幼苗芽长、根长与根数均极显著下降(P<0.01,下同),相对抑制率表现为根长>芽长>根数。参试材料可分为强耐盐类型、中耐盐类型和弱耐盐类型,其中强耐盐类型芽长和根数抑制率极显著低于中耐盐和弱耐盐类型,而根长抑制率与其他类型无显著差异(P>0.05)。强耐盐材料中品系13G143芽长、根长和根数相对抑制率较低,分别为11.89%、25.36%和10.08%,均低于对照长白9号。【结论】150mmol/L Na Cl胁迫下,水稻品系13G143耐盐碱能力较强,可作为水稻幼苗期耐盐亲本材料应用。
基金supported by the China Postdoctoral Science Foundation(No.2012M511005)National Key Technology Support Program of China(No.2015BAC02B02)+6 种基金the Agro-scientific Research Programs in Public Interest(No.201303102)National Natural Science Foundation of China(No.31501263)the Postdoctoral Financial Assistance of Heilongjiang Province(No.LBH-Z12232)the Scientific Research Initiation Fund for Introduction of Ph.D Talent of Heilongjiang Academy of Agricultural Sciences(No.201507-14)the State Key Program of China(No.2016YFD0300900)the Major Project of Research and Development of Applied Technology of Heilongjiang Province(No.GA15B101)the Provincial Matching Funds to the National Foundation of Applied Technology Research and Development Program in Heilongjiang Province(No.GX16B002)
文摘Water regime and nitrogen（N） fertilizer are two important factors impacting greenhouse gases（GHG） emission from paddy field, whereas their effects have not been well studied in cold region. In this study, we conducted a two-year field experiment to study the impacts of water regime and N fertilizer on rice yields and GHG emissions in Harbin, China, a cold region located in high latitudes. Our results showed that intermittent irrigation significantly decreased methane（CH4） emission compared with continuous flooding, however,the decrement was far lower than the global average level. The N2O emissions were very small when flooded but peaked at the beginning of the disappearance of floodwater. The N fertilizer treatments increased CH4 emissions at low level（75 kg N/ha）. But both CH4 and N2O emissions were uninfluenced at the levels of 150 kg N/ha and 225 kg N/ha. Rice yields increased under intermittent irrigation and were highest at the level of 150 kg N/ha. From our results, we recommended that the intermittent irrigation and 150 kg N/ha as the ideal water regime-nitrogen fertilizer incorporation for this area to achieve low GHG emissions without impacting rice yields.
文摘Ammonia volatilization loss and ^15N balance were studied in a rice field at three different stages after urea application in Taihu Lake area with a micrometeorological technique. Factors such as climate and the NH4^＋-N concentration in the field floodwater affecting ammonia loss were also investigated. Results show that the ammonia loss by volatilization accounted for 18.6%-38.7% of urea applied at different stages, the greatest loss took place when urea was applied at the tillering stage, the smallest at the ear bearing stage, and the intermediate loss at the basal stage. The greatest loss took place within 7 d following the fertilizer application. Ammonia volatilization losses at three fertilization stages were significantly correlated with the ammonium concentration in the field floodwater after the fertilizer was applied. ^15N balance experiment indicated that the use efficiency of urea by rice plants ranged between 24.4% and 28.1%. At the early stage of rice growth, the fertilizer nitrogen use efficiency was rather low, only about 12%. The total amount of nitrogen lost from different fertilization stages in the rice field was 44.1%-54.4%, and the ammonia volatilization loss was 25.4%-33.3%. Reducing ammonia loss is an important treatment for improving N use efficiency.
