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4篇 您的检索式:作者名="AMIR KASSAM"
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1Current status of adoption of no-till farming in the world and some of its main benefits显示文摘In 1999 no-tillage farming,synonymous of zero tillage farming or conservation agriculture,was adopted on about 45 million ha world wide,growing to 72 million ha in 2003 and to 111 million ha in 2009,corresponding to an growth rate of 6 million ha per annum.Fastest adoption rates have been experienced in South America where some countries are using no-tillage farming on about 70%of the total cultivated area.Opposite to countries like the USA where often fields under no-tillage farming are tilled every now and then,more than two thirds of the area under no-tillage systems in South America is permanently not tilled;in other words once adopted,the soil is never tilled again.The spread of no-tillage systems on more than 110 million ha world-wide shows the great adaptability of the systems to all kinds of climates,soils and cropping conditions.No-tillage is now being practiced from the artic circle over the tropics to about 50ºlatitude south,from sea level to 3,000 m altitude,from extremely rainy areas with 2,500 mm a year to extremely dry conditions with 250 mm a year.No-till farming offers a way of optimizing productivity and ecosystem services,offering a wide range of economic,environmental and social benefits to the producer and to the society.At the same time,no-till farming is enabling agriculture to respond to some of the global challenges associated with climate change,land and environmental degradation,and increasing cost of food,energy and production inputs.The wide recognition of no-till farming as a truly sustainable system should ensure the spread of the no-till technology and the associated practices of organic soil cover and crop rotation,as soon as the barriers to its adoption have been overcome,to areas where adoption is currently still low.The widespread adoption globally also shows that no-tillage farming cannot any more be considered a temporary fashion or a craze;instead largely through farmers’own effort,the system has established itself as a farming practice and a different way of thinking about sustainable agro-ecosystem management that can no longer be ignored by scientists,academics,extension workers,farmers at large as well as equipment and machine manufacturers and politicians.Rolf Derpsch Theodor Friedrich Amir Kassam Li Hongwen 2010International Journal of Agricultural and Biological Engineering2010,3,1:18
2Improving the phenotypic expression of rice genotypes:Rethinking “intensification” for production systems and selection practices for rice breeding显示文摘Intensification in rice crop production is generally understood as requiring increased use of material inputs: water, inorganic fertilizers, and agrochemicals. However, this is not the only kind of intensification available. More productive crop phenotypes, with traits such as more resistance to biotic and abiotic stresses and shorter crop cycles, are possible through modifications in the management of rice plants, soil, water, and nutrients, reducing rather than increasing material inputs. Greater factor productivity can be achieved through the application of new knowledge and more skill, and(initially) more labor, as seen from the System of Rice Intensification(SRI), whose practices are used in various combinations by as many as 10 million farmers on about 4 million hectares in over 50 countries. The highest yields achieved with these management methods have come from hybrids and improved rice varieties, confirming the importance of making genetic improvements. However,unimproved varieties are also responsive to these changes, which induce better growth and functioning of rice root systems and more abundance, diversity, and activity of beneficial soil organisms. Some of these organisms as symbiotic endophytes can affect and enhance the expression of rice plants' genetic potential as well as their phenotypic resilience to multiple stresses, including those of climate change. SRI experience and data suggest that decades of plant breeding have been selecting for the best crop genetic endowments under suboptimal growing conditions, with crowding of plants that impedes their photosynthesis and growth, flooding of rice paddies that causes roots to degenerate and forgoes benefits derived from aerobic soil organisms, and overuse of agrochemicals that adversely affect these organisms as well as soil and human health. This review paper reports evidence from research in India and Indonesia that changes in crop and water management can improve the expression of rice plants' genetic potential, thereby creating more productive and robustphenotypes from given rice genotypes. Data indicate that increased plant density does not necessarily enhance crop yield potential, as classical breeding methods suggest. Developing cultivars that can achieve their higher productivity under a wide range of plant densities—breeding for density-neutral cultivars using alternative selection strategies—will enable more effective exploitation of available crop growth resources. Density-neutral cultivars that achieve high productivity under ample environmental growth resources can also achieve optimal productivity under limited resources, where lower densities can avert crop failure due to overcrowding. This will become more important to the extent that climatic and other factors become more adverse to crop production. Focusing more on which management practices can evoke the most productive and robust phenotypes from given genotypes is important for rice breeding and improvement programs since it is phenotypes that feed our human populations.Norman Uphoff Vasilia Fasoula Anas Iswandi Amir Kassam Amod K.Thakur 2015The Crop Journal2015,3,3:3
3Identification of anovulation and transient luteal function using a urinary PdG ratio algorithm显示文摘AMIR KASSAM JAMES W OVERSTREET CHRISTINE SNOW-HARTER 1996Envi- ronmental Health Perspectives1996,104,4:1
4A review of agricultural research issues raised by the system of rice intensification (SRI) from Madagascar: opportunities for improving farming systems for resource-poor farmers显示文摘Willem A. Stoop Norman Uphoff Amir Kassam 2002Agricultural Systems2002,,3:1
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