Yield Decrease of Corn Sown into Italian Ryegrass by Minimum Tillage

The objective of this study was to determine the factor causing yield decrease of corn (Zea mays L.) sown into Italian ryegrass (Lolium multiflorum Lam.) by minimum tillage. 5 plots with 2 replications were made, consisting of the number of harvest times of Italian ryegrass, tillage system, and herbicide application. They were 1CT (Italian ryegrass was harvested once/conventional tillage), 1MT (once/minimum tillage), 1MTH (once/MT/herbicide), 2CT (twice/ CT), and 2MT (twice/MT). 1MT produced lowest corn yield and highest Italian ryegrass litter. This observation suggested that corn yield decrease was attributed to competition with Italian ryegrass regrowth. NAR in 1MT after 5 leaf stage indicated considerable decline in comparison with the others. Relative light intensity was under 5% in 1MT, in which the corn couldn\u27t grow. There was no certain trend between plots in soil property. From these results, it was concluded that shading caused by Italian ryegrass was the main factor of yield decrease of corn in minimum tillage

Assessment of Technologies for Reducing CO2 Emission

There are a wide variety of technologies for reducing CO2 emissions, of which a greater part are those of energy technologies. The paper aims at assessing these technologies with regional differences of technology characteristics taken into account. The first part examines merits and demerits of individual technology, and thus envisages its possible future. The second part describes a global energy model, which generates comprehensive long term future scenarios of energy and CO2 emission in various regions of the world