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Dilemma for Brazilian farmers

Glyphosate burndown spray has failed to control Conyza Soybean growers in Brazil are facing a dilemma. More land under no-till

Description

Also known as conservation tillage or zero tillage is a way of growing crops from year to year without disturbing the soil through tillage ie cultivating the soil usually with tractor-drawn implements.

Authoritative On-line References and Resources

No-till.com:  A portal for on-line information about no-till farming.
is saving its soil and reducing energy use, but many no-till farmers are now finding that glyphosate resistant weeds are threatening future success.  No-till cropping has been very successful in curtailing soil erosion

Description

Displacement of solids (soil, mud, rock and other particles) usually by the agents of currents such as, wind, water, or ice by downward or down-slope movement.

Authoritative On-line References and Resources

http://soilerosion.net/ This site brings together reliable information on soil erosion from a wide range of disciplines and sources. It aims to be the definitive internet source for those wishing to find out more about soil loss and soil conservation.
, with its roots in the 1970s when the British company ICI began experimenting with the use of paraquat for weed control. Later, glyphosate was introduced and, with its advantage of controlling perennial weeds

Description

Weeds that return year after year. Some die back in the winter but their roots remain alive and shoots reappear in spring; some don't die back and grow in size and stature the next season.

Authoritative On-line References and Resources

The International Weed Science Society represents individual associations around the world.
, has been used increasingly, year-on-year, for three decades.
Glyphosate’s original use in soybeans was as a burndown herbicide to remove weeds before planting. However, since glyphosate tolerant GM crops became available glyphosate has also been used as a selective herbicide

Description

A chemical product used for eliminating certain types of weeds only (ie either grasses or broadleaved weeds) and not affecting specified crops.

Authoritative On-line References and Resources

http://www.weeds.iastate.edu/ An invaluable source of contemporary information about herbicides and weeds from Iowa State University.
to control weeds competing with the growing crop.
The result in Brazil has been a developing problem of resistant weeds in the southern soybean growing states of Paraná and Rio Grande do Sul. Read more ...

Better weed management in bananas

Bananas are an important export from the Philippines Lower costs and favorable environmental effects when using paraquat: these were the key conclusions from a four-year comparison of weed control methods in bananas, recently completed by the University of the Philippines. New plantations are being established on more sloping land where soil erosion poses a real threat to sustainable production. Filipino authorities estimate that 623 million tonnes of soil are lost annually from 28 million hectares of land. In the field trial, traditional methods of hand weeding and slashing with a machete called a bolo were compared to a monthly spray program in a sequence of two applications of paraquat followed by one of glyphosate. Managing the weed cover in this way was very successful in reducing soil erosion in both regimes to less than 1 tonne/ha/year, even though plots were laid out on gradients of up to 25%. Read more ... 

Spray-topping with paraquat improves grass-cereal rotations 

Annual ryegrass ready to set seedParaquat can be used to improve the species composition of pastures for livestock grazing and reduce the carryover of grass weed seeds into following cereal crops. Spray-topping involves spraying paraquat at a low rate to prevent the setting of viable seed. The species composition of a pasture is important for maximum livestock productivity. Weed grasses

Description

The leaves are "narrow" as opposed to the "broad" leaves of broadleaved weeds. Also called 'monocots' having one seed leaf opposed to 'dicots' having two seed leaves.

Authoritative On-line References and Resources

The International Weed Science Society represents individual associations around the world. 
are of inferior nutritional value; compete with desirable species; are hosts for pests and diseases; and can even be harmful to livestock. 
Spray-topping is also used when a pasture is to be followed by a crop of wheat. Yields may be increased by reducing competition from grass weeds such as annual ryegrass, and also through a lower incidence of the root disease take-all (Gaemannomyces graminis) carried on the ryegrass and higher soil nitrogen availability. Read more ...