The critical period for weed control (CPWC) is the period in the crop growth cycle during which weeds must be controlled to prevent unacceptable yield losses. Field studies were conducted in 2005 and 2006 in the University of Birjand at the south east of Iran to determine CPWC of corn using a randomized complete block design with 14 treatments and three replications. The treatments consisted of...

This study was conducted to determine whether selecting an optimum sowing date couldimprove yield. The experiment consisted of sowing a film-covered, drip-irrigated cotton field onfour sowing dates from April to May in 2011-2012 at the Agrometeorological ExperimentalStation of Wulanwusu, which was in an arid region of north-western China. Late sowing datesproduced less yield and water-use effic...

Objective:  In addition to the role of organic matter in plant nutrition, this material improves soil quality, physical structure, ventilation and water supply, and ease of penetration and expansion is rooted deep in the soil surface. Effects of organic matter due to climatic factors, soil characteristics may vary from region to region, resulting in organic materials management must be given to...