The Eleventh Regional Wheat Workshop For Eastern ... - Cimmyt

Survey ofweed community structure - KefYalew et at.
Another aspect of loss reflected due to weeds involves that of market price of produce.
Fanners carrying wheat grain infested with weed seed always get on average 30% less price
than those fanners carrying clean seed. This has direct relation with the type of weed
management that farmers exercise.
New weed problems. Farmers were asked if they came across new weed species or if weeds
that had not been important had recently become so. Accordingly, 42.3% of the fanners
interviewed responded 'no' while 57.7% responded 'yes'. Of the 57.7% responded 'yes'
28.9% identified Bromus pectinatus, 5.9% Argemone mexicana and 2% Polygonum
convolvulus. The rest identified weed species like Phalaris minor, Galium spurium and
Guizotia scabra as new weed problems in their area.
CONCLUSIONS AND RECOMMENDATIONS
In the current survey, the following conclusions and recommendations can be drawn for
researchers, extension workers and fanners.
• The survey has documented th~ species and their relative importance in wheat.
• The data from current survey is the first of its kind in the surveyed area; therefore, the
data can be used in the future to detennine the impact of crop management and other
factors on the weed species composition and community structure.
• The first eight major weeds with high mean density and dominance are Polygonum
nepalense, Phalaris minor, Bromus pectinatus, Galium spurium, Guizotia scabra,
Galinsoga parvijlora, Cotula abyssinica, Anagallis arvensis.
• Since the major weed species are limited in number, designing an effective weed
management strategy for the surveyed area should be relatively simple.
• Fanners and development workers should give due attention to new problem weeds
before they become difficult for management.
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