Weed Management In Crops

Abstract
Weed management in different crop is the most laborious and cost concerned options in pest management in agricultural production from the past era of modern weed control research. Joint effort of combined weed management options considered for sustainable crop establishment in a profitable way. Weed management is the application of vast concern of cultural and manual, mechanical, chemical and biological practices to suppress weed infestation in different crops. The scientific knowledge should be consider of cropping systems would minimize the crop damage by weeds that by in depth study in survive mechanism and shifting of weed population. Development of effective chemicals and its resistant to weeds and other crops also need to be

Although, some weeds have been designated as injurious to all crops, or ecosystems, or human, or livestock, are called noxious weed or injurious weed (Nyarko and De Datta, 1990). Weed is the major threat for sustainable crop production to feed the people and animal of the whole world. Weed management practices are the most ancient part of crop cultivation and become major constant to agricultural productivity and environmental concern (Upadhyaya and Blackshaw, 2007). Integration of weed management is effective and profitable for long term weed management in crops then a sole method. Buhler et al. (2000) stated that the integrated weed management is the effective approach by integration of cultural, mechanical, biological and chemical method to reduce the effect of weed under critical levels. Weed management strategies deflected from non-chemical approach to the use of herbicide option for not only increasing its availability and selective effectiveness but also popularize for the shortage of labor from the World War II (Upadhyaya and Blackshaw, 2007) and from mid 80s in Bangladesh (Ahmed et al., 2010; Naylor, 1994). Effective weed management consists of many factors that vary from crop to crop and year to year depending upon different cropping system. The planting date, spacing, climatic conditions, seedbed preparation, seed quality, stand establishment and

The number of species and density of weed in an area depends on the land use pattern, associated crops and its ecological conditions (Tanveer et. al., 2013). The one-third weed species are monocotyledonous and the remaining two third plants are dicotyledonous of the common weeds that found in Bangladesh. Echinochloa crus-galli, Echinochloa colonum, Cyperus rotundus, Cyperus iria, Fimbristylis miliacea, Chenopodium album, Eichhornia crassipes Cynodon dactylon, etc are the most important weed species of Bangladesh (Islam,