The rice and wheat cropping pattern is one of the main cropping systems in the world. A large number of research results showed that successive cropping of rice and wheat resulted in a series of problems such as hinde...The rice and wheat cropping pattern is one of the main cropping systems in the world. A large number of research results showed that successive cropping of rice and wheat resulted in a series of problems such as hindering nutrition absorption, gradual degeneration of soil fertility, decline of soil organic matter, and increased incidence of diseases and pests. In China, especially in the Chengdu plain where rice-wheat cropping system is practiced, productivity and soil fertility was enhanced and sustained. This paper reviews the relevant data and experiences on rice-wheat cropping in the Chengdu Plain from 1977 to 2006. The principal sustainable strategies used for rice-wheat cropping systems in Chengdu Plain included： 1） creating a favorable environment and viable rotations; 2） balanced fertilization for maintenance of sustainable soil productivity; 3） improvement of crop management for higher efficiency; and 4） use the newest cultivars and cultivation techniques to upgrade the production level. Future research is also discussed in the paper as： 1） the constant topic： a highly productive and efficient rice-wheat cropping system for sustainable growth; 2） the future trend： simplified cultivation techniques for the rice-wheat cropping system; 3） the foundation： basic research for continuous innovation needed for intensive cropping. It is concluded that in the rice-wheat cropping system, a scientific and reasonable tillage/cultivation method can not only avoid the degradation of soil productivity, but also maintain sustainable growth in the long run.展开更多
Rice-wheat cropping system (RWCS) is one of the most important cropping systems in South Asia. However, sustainability of this system is under threat owing to several factors, of which deficiency of micronutrients par...Rice-wheat cropping system (RWCS) is one of the most important cropping systems in South Asia. However, sustainability of this system is under threat owing to several factors, of which deficiency of micronutrients particularly zinc (Zn), boron (B) and manganese (Mn) is one of the major problems. Continuous rotation of rice and wheat, imbalanced fertilizer use and little/no use of micronutrient-enriched fertilizers induce deficiencies of Zn, B and Mn in the RWCS of South Asia. Here we review that (i) imbalanced fertilizer use and organic matter depletion deteriorate soil structure resulting in low efficiency of applied macro- and micro-nutrients in RWCS.(ii) The micronutrients (Zn, B and Mn) are essentially involved in metabolism of rice and wheat plants, including chlorophyll synthesis, photosynthesis, enzyme activation and membrane integrity.(iii) Availability and uptake of Zn, B and Mn from rhizosphere depend on the physico-chemical soil properties (which differ under aerobic and anaerobic conditions) including soil pH, soil organic matter, soil moisture and interaction of these micronutrients with other nutrients.(iv) Plant ability to uptake and utilize the nutrients is affected by several plant factors such as root architecture, root hairs, transport kinetics parameter and root exudates.(v) Crop management and application of these microelements can help correct the micronutrients deficiency and enhance their grain concentration.展开更多
气候变暖存在明显的昼夜不对称性,夜间增温显著高于白天。设计可靠的田间增温设施,研究作物系统对夜间增温的响应与适应意义显著。参考国际相关增温系统,于2006—2009年在江苏南京设计并运行了我国首个农田开放式夜间增温系统(FATI,Free...气候变暖存在明显的昼夜不对称性,夜间增温显著高于白天。设计可靠的田间增温设施,研究作物系统对夜间增温的响应与适应意义显著。参考国际相关增温系统,于2006—2009年在江苏南京设计并运行了我国首个农田开放式夜间增温系统(FATI,Free Air Temperature Increased),对稻麦进行夜间主动增温试验,监测系统温度、麦田土壤水分和作物生育进程和产量,以评价该系统的可行性和对稻麦的增温效果。结果表明,该系统有效且均匀的增温范围为4m2,增温效果明显。在测试用人工草坪上,晴天、阴天和雨天3种天气情况下,该系统4m2有效增温范围内地表的夜温平均升高2.4℃、2.3℃和2.1℃。在草坪的垂直层面上,该系统可以使距地下5cm、地表、地上40cm和90cm4个层次的夜温平均分别升高1.2℃、2.2℃、0.7℃和2.3℃。在稻麦两熟农田中,稻季全生育期地下5cm、地表、植株中部和冠层的夜温平均分别升高0.7℃、0.6℃、1.0℃和1.6℃,麦季相应层次可升高1.2℃、1.5℃、1.8℃和1.9℃。在稻麦全生育期内,增温小区各层温度的变化动态与未增温区的一致。另外,该系统未改变麦田耕层土壤水分分布特征,尽管耕层土壤含水量略有降低,0～25cm内各层土壤含水量的降幅均在0.99～1.62个百分点以内,与未增温区差异不显著。夜间增温可以显著缩短作物前期生育期,使稻麦始穗期分别提早2.5d和11.5d;同时,夜间增温使水稻平均减产4.51%,但小麦增产18.30%。尽管在作物的不同生育期,该设施的增温幅度有所差异,但这与田间实际情况下不同季节气候变暖幅度不同之特征一致。因此,该开放式夜间增温系统符合气候变暖的温度变化特征,可以满足水稻和小麦所代表的典型作物系统对夜间增温的响应与适应的试验要求。展开更多
基金funded by the National Key Technologies Research and Development Program of China(2006BAD02A05)the Science and Technology Project for Public (Agriculture)the Ministry of Agriculture, China (200903050-4)
文摘The rice and wheat cropping pattern is one of the main cropping systems in the world. A large number of research results showed that successive cropping of rice and wheat resulted in a series of problems such as hindering nutrition absorption, gradual degeneration of soil fertility, decline of soil organic matter, and increased incidence of diseases and pests. In China, especially in the Chengdu plain where rice-wheat cropping system is practiced, productivity and soil fertility was enhanced and sustained. This paper reviews the relevant data and experiences on rice-wheat cropping in the Chengdu Plain from 1977 to 2006. The principal sustainable strategies used for rice-wheat cropping systems in Chengdu Plain included： 1） creating a favorable environment and viable rotations; 2） balanced fertilization for maintenance of sustainable soil productivity; 3） improvement of crop management for higher efficiency; and 4） use the newest cultivars and cultivation techniques to upgrade the production level. Future research is also discussed in the paper as： 1） the constant topic： a highly productive and efficient rice-wheat cropping system for sustainable growth; 2） the future trend： simplified cultivation techniques for the rice-wheat cropping system; 3） the foundation： basic research for continuous innovation needed for intensive cropping. It is concluded that in the rice-wheat cropping system, a scientific and reasonable tillage/cultivation method can not only avoid the degradation of soil productivity, but also maintain sustainable growth in the long run.
文摘Rice-wheat cropping system (RWCS) is one of the most important cropping systems in South Asia. However, sustainability of this system is under threat owing to several factors, of which deficiency of micronutrients particularly zinc (Zn), boron (B) and manganese (Mn) is one of the major problems. Continuous rotation of rice and wheat, imbalanced fertilizer use and little/no use of micronutrient-enriched fertilizers induce deficiencies of Zn, B and Mn in the RWCS of South Asia. Here we review that (i) imbalanced fertilizer use and organic matter depletion deteriorate soil structure resulting in low efficiency of applied macro- and micro-nutrients in RWCS.(ii) The micronutrients (Zn, B and Mn) are essentially involved in metabolism of rice and wheat plants, including chlorophyll synthesis, photosynthesis, enzyme activation and membrane integrity.(iii) Availability and uptake of Zn, B and Mn from rhizosphere depend on the physico-chemical soil properties (which differ under aerobic and anaerobic conditions) including soil pH, soil organic matter, soil moisture and interaction of these micronutrients with other nutrients.(iv) Plant ability to uptake and utilize the nutrients is affected by several plant factors such as root architecture, root hairs, transport kinetics parameter and root exudates.(v) Crop management and application of these microelements can help correct the micronutrients deficiency and enhance their grain concentration.
文摘气候变暖存在明显的昼夜不对称性,夜间增温显著高于白天。设计可靠的田间增温设施,研究作物系统对夜间增温的响应与适应意义显著。参考国际相关增温系统,于2006—2009年在江苏南京设计并运行了我国首个农田开放式夜间增温系统(FATI,Free Air Temperature Increased),对稻麦进行夜间主动增温试验,监测系统温度、麦田土壤水分和作物生育进程和产量,以评价该系统的可行性和对稻麦的增温效果。结果表明,该系统有效且均匀的增温范围为4m2,增温效果明显。在测试用人工草坪上,晴天、阴天和雨天3种天气情况下,该系统4m2有效增温范围内地表的夜温平均升高2.4℃、2.3℃和2.1℃。在草坪的垂直层面上,该系统可以使距地下5cm、地表、地上40cm和90cm4个层次的夜温平均分别升高1.2℃、2.2℃、0.7℃和2.3℃。在稻麦两熟农田中,稻季全生育期地下5cm、地表、植株中部和冠层的夜温平均分别升高0.7℃、0.6℃、1.0℃和1.6℃,麦季相应层次可升高1.2℃、1.5℃、1.8℃和1.9℃。在稻麦全生育期内,增温小区各层温度的变化动态与未增温区的一致。另外,该系统未改变麦田耕层土壤水分分布特征,尽管耕层土壤含水量略有降低,0～25cm内各层土壤含水量的降幅均在0.99～1.62个百分点以内,与未增温区差异不显著。夜间增温可以显著缩短作物前期生育期,使稻麦始穗期分别提早2.5d和11.5d;同时,夜间增温使水稻平均减产4.51%,但小麦增产18.30%。尽管在作物的不同生育期,该设施的增温幅度有所差异,但这与田间实际情况下不同季节气候变暖幅度不同之特征一致。因此,该开放式夜间增温系统符合气候变暖的温度变化特征,可以满足水稻和小麦所代表的典型作物系统对夜间增温的响应与适应的试验要求。
