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Groundnut being mainly grown during rainy season encounters several weeds which grow luxuriantly and dominate during this season as compared to rabi/summer season. Weeds dominating in Groundnut crop

Weed competition is maximum during the early stages of groundnut crop because of slow initial growth and less foliage cover.
As the crop do not grow tall weeds dominate during later part of crop growth also.

 

Weeds in groundnut crop not only compete with the crop for nutrients, water, and light, but also interfere with harvesting of the crop. Unless good weed control is achieved, substantial yield losses will occur. A reduction of 20 to 45% in yield due to weeds was reported from weed control experiments.
The critical period of weed competition is estimated to be 2-6 weeks after sowing. A variety of weeds are associated with groundnut crop. These weeds comprise of diverse plant species of annual grasses and seasonal broad leaved weeds.
The list of major weeds that grow in ground crop are shown with their images in the following screens  

Common Broad-leaf weeds in groundnut

Botanical name    Abutilon indicum	Common Name Indian mallow
Alysicarpus sp.	One-leaf clover
Argemone mexicana	Mexican poppy
Celosia argentina	White cock's comb
Borreria articularis	Button plant
Gynondropsis (Cleome) spp	Wild spider flower
Digera arvensis	Kundra
Corchorus olitorius	Jew's mallow
Portulaca spp.	Common purslane
Vernonia cinerea >	Little iron weed
Leucas aspera	Dronapushpi
Xanthium strumarium	Cocklebur
Anagallis arvensis	Scarlet Pimpernel
Bidense pilosa	Spanish needle
Eclipta spp.	False daisy
Ipomea spp	Morning glory
Tridax procumbence	Tridax daisy, wild daisy
Euphorbia spp.	Spurge
Amaranthus spp.	Pigweed
Mollugo verticillata	Carpet-weed

Common Grass (monocots) weeds in groundnut

Botanical name	Common Name
Chloris spp.	Fingergrass
Digetaria sanguinalis	Crabgrass
Dactyloctenium aegyptium	Crowfootgrass
Echinocloa spp.	Barnyard grass
Commelina spp.	Benghal dayflower
Paspalum distichum	Water couch
Eleusine indica	Goose grass
Eragrostis spp.	Love grass
Setaria spp.	Foxtail
Cynodon dactylon	Bermuda grass

Common Sedges in groundnut

Botanical name	Common Name
Cyperus rotundus	Purple nut sedge
Cyperus esculentus	Yellow nut sedge
Cyperus defformis	Nut sedge
Cyperus compressus	Nut sedge