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weed control Tag

जैवशाकनाशी:  जैविक कृषि में खरपतवार प्नबंधन हेतू उपकरण   In irrigated agriculture, weed control through chemical herbicides, creates spray drift hazards and adversely affects the environment. Besides, pesticide residues (herbicides) in food commodities, directly or indirectly affect human health. These lead to the search for an alternate method of weed management, which is eco-friendly. In this regard the biological approach is gaining momentum. Utilization of plant pathogens for weed control was first reported in the early 1900s, but the concept of using bioherbicides to control weeds attracted wide interest among weed scientists and plant pathologists after the Second World War. The earliest experiments simply involved fungus Fusarium oxysporum against prickly pear cactus (Opuntia ficusindica (L.) Mill.). In the 1950s, the Russians mass produced the spores of Alternaria cuscutacidae and applied them to the parasitic weed dodder (Cuscata spp.). In 1963, the Chinese mass produced a different fungus (Colletotrichum gloeosporioides) for Cuscata spp. They called their mycoherbicide “LuBao” and an improved formulation is still in use today. Commercial bioherbicides first appeared in the market in USA in early 1980s with the release of the products Devine, Collego and Biomal. Success stories of these products and the expectation of obtaining perfect analogues of chemical herbicides have opened a new vista for weed management. Plant pathologists and weed...

मृदा सोलराईजेसन - खरपतवार प्रबंधन के एक अच्‍छी तकनीक The impact of pesticide use on the environment is now well documented, and a more wide spread adoption of integrated weed management strategies and tactics is recommended in sustainable agriculture systems. Soil solarization is a novel technique of controlling soil borne pests including weeds. This hydrothermal process occurs in moist soil which is covered by a transparent plastic film for 4-6 weeks and exposed to sunlight during the warm summer months. The practice was first reported from Germany in 1888 and was first used commercially by USA in 1897. Soil propagules, as weed seeds, offer a wide range of tolerance to high temperatures, conditioning the long term success of weed control by solarization. It seems probably that not only harmful organisms, but also beneficial organisms are killed by using soil fumigants for soil disinfestations. Principles of solarization Solar heating involves the use of heat as lethal agent for tarps for capturing solar energy by means of transparent polythene soil mulches. The thin polythene mulch allows the maximum transmission of solar radiation through moist soil and reduces moisture loss from soil through evaporation. Increase in soil temperature was achieved through improved heat conduction within the soil owing to its higher moisture levels. The principle behind...