Description : A period in the ontogeny of crop at which maximum crop weed competition occurs is called a). Economic threshold b). Gain threshold c). Competitive threshold d). None
Last Answer : d). None
Description : Critical period of crop weed competition in sugarcane is a). 30-40 days b). 30-120 days c). 10-40 days d). 15-30 days
Last Answer : b). 30-120 days
Description : The period at which maximum crop weed competition occurs is a). Critical period b). Dormancy c). Flaming d).Threshold
Last Answer : a). Critical period
Description : Wheat and bajra have critical period of crop-weed competition a).10-20 days b).15-30 days c). 30-45 days d). 20-40 days
Last Answer : c). 30-45 days
Description : With poor weed management, a field could shift to a). Predominant weed species b). Species not effectively controlled c). Species not responded to control meas ures d). All the above
Last Answer : d). All the above
Description : Weed species which has nematicidal prop erty a). Crotolaria b). Parthenium c). Eichhornia sp d). All of these
Last Answer : d). All of these
Description : Number of weed species identified in the world a). 30 b). 300 c). 3000 d). 30000
Last Answer : d). 30000
Description : Weed species wgich can tolerate so larisation effect a). Phalaris minor b). Sorghum halepense c). Alopecurus myosuroides d). Lolium temulentum
Last Answer : b). Sorghum halepense
Description : A nitrogen fixing weed species in wheat a). Lathyrus aphaca b). Medicago denticulata c). Vicia sativa d). All
Last Answer : d). All
Description : Factors affecting weed-crop interference are a). Period of weed growth b). Soil and climate influence c). Plant species effects d). All
Description : Biological weed control is not successful because a). Not possible to eradicate weed b). Bioagents are weed specific c). Controlled only introduced weeds d). All of these
Description : Multiple resistance is the phenomenon in which a weed is resistant to two or more herbicides having a). same mechanisms of action b). different mechanisms of action c). same chemistry d). different chemistry
Last Answer : b). different mechanisms of action
Description : Weed intensity if number of weeds is 110/m2 and wheat plants are 90/m2. a). 55% b). 110% c). 22.5% d). 77.5%
Last Answer : a). 55%
Description : The striving of two or more individuals for the same object a). Allelopathy b). Competition c). Co-operation d). None of these
Last Answer : b). Competition
Description : Herbicide Resistance can be managed through a). Stop to Use of herbicides with the same mechanism of action b). Use proactive weed control c). Use of post emergence herbicides with at least one mechanism of action d). All of the above
Last Answer : d). All of the above
Description : The ecological phenomenon of plant-plant interference a). Competition b). Allelopathy c). Both d). None
Last Answer : c). Both
Description : Struggle for survival and existence is called a). Critical period b). Competition c). Dormancy d). Persistence
Description : If Echinochloa falls in frequency class ‘E’, the weed community is said to be a). Contiguous b). Heterogenous c). Homogenous d). Random
Last Answer : c). Homogenous
Description : If weed population is 70/m2 and the crop 140/ m2, weed intensity would be a). 33.3% b). 66.6% c). 50% d). 73.4%
Last Answer : a). 33.3%
Description : If the count of Echinochloa in weedy check is 70 and that in a treatment 25/m2, weed control efficiency will be a). 54.3% b). 64.3% c). 73.4% d). 79.6%
Last Answer : b). 64.3%
Description : If the yield from weed free is 3500 kg and that from weedy 1500 kg/ha, weed index would be a). 57.1% b). 133.3% c). 45.0% d). 25.6%
Last Answer : a). 57.1%
Description : . A ceremonial weed a). Cynodon dactylon b). Datura stramonium c). Tagetus sp d). All of these
Description : A ceremonial weed a). Asparagus racemosus (Shatawari) b). Cynodon dactylon (Dhoob ghaas) c). Nelumbo nucifera (Lotus flower) d). All of these
Description : A ceremonial weed a). Asparagus racemosus (Shatawari) b). Cynodon dactylon (Dhoob ghaas) c). Both a and b d). Digitaria sanguinalis
Last Answer : c). Both a and b
Description : To manage grassy weed flora in barley which of the herbicides is to be applied a). Pendimethalin b). Isoproturon c). a and b d). Metsulfuron
Last Answer : c). a and b
Description : To manage mixed weed flora in barley which of the herbicides is to be applied a).2,4-D b). Isoproturon c). a and b as tank mix d). None of these
Last Answer : c). a and b as tank mix
Description : A herbicide requiring good spray coverage of all foliage for effective control of a weed population a).Paraquat b). Glyphosate c). Atrazine d). Isoproturon
Last Answer : a).Paraquat
Description : A curvilinear relationship between weed density and crop yield was reported by a). Zimdahl 1980 b). Roberts and Bonds (1975) c). Cousens et al (1985) d). None of these
Last Answer : b). Roberts and Bonds (1975)
Description : The sigmoidal relationship between weed density and crop yield was proposed by a).Zimdahl 1980 b). Roberts and Bonds (1975) c). Cousens et al (1985) d). None of these
Last Answer : a).Zimdahl 1980
Description : A weed accumulate over 550 ppm of Zn in its dry matter a). Digitaria b). Setaria lutescens c). Portulaca d). Chenopodium
Last Answer : b). Setaria lutescens
Description : A natural pre-emergence weed control in turf grass a). Corn gluten meal b). Bialaphos c). Sulcotrione d). Cinmethylin
Last Answer : a). Corn gluten meal
Description : . A non-competitive crop requiring weed free period of three or more months a). Maize b). Rice c). Soybean d). Onion
Last Answer : d). Onion
Description : The effective solution to manage weed shifts a). Herbicide combinations b). Herbicide rotations c). Crop rotations d). All
Description : The competitive crop requiring weed free period of about 3-4 weeks a). Soybean b). Carrot c). Garlic d). Onion
Last Answer : a). Soybean
Description : A noxious weed of South India a). Cynodon b). Cyperus c). Wild brinjal d). All
Description : Herbicide which increase tuber size be sides weed control in potato a). EPTC b). Fluchloralin c). Pendimethalin d). Atrazine
Last Answer : a). EPTC
Description : Largest pre-emergence herbicide for weed control in citrus and pineapple orchards a). Atrazine b). Metham c). Allyl d). All
Last Answer : b). Metham
Description : A very potent herbicide for the control of perennial, broad-leaved weed and brushes a). Atrazine b). 2,4-D c). Picloram d). Amitrole
Last Answer : c). Picloram
Description : Effective rate (kg/ha) of 2,4-D for weed control a). 0.2-0.5 b). 0.5-1.0 c). 2 d). 5
Last Answer : b). 0.5-1.0
Description : Direct contact herbicide application can be achieved by a). Re-circulating sprayer b). Weed wick wiper c). Roller applicator d). All
Description : . Klamath weed (Hypericum perforatum) is controlled by an insect a). Chrysolina hyperici (Beetle) b). Chrysolina gamellata (Beetle) c). Agrilus hyperici (Root borer) d). All of these
Description : Important quality of bioagents a). Attack only host plant b). Free from predators/parasites and quick adoption to new environment c). Able to kill reproductive parts of weed d). All of these
Description : An eradication method of weed control a). Killing underground parts of weeds by tillage b). Using soil sterilants c). Repeated foliar application on perennial weeds d). All of these
Description : . A preventive method of weed control a). Using weed free seeds b). Using clean machineries c). Following quarantine measures d). All of these
Description : The weed less responsive to nitrogen a). Cyperus b). Cynodon c). Both a and b d). None of these
Description : Cultural practice reducing weed population a). Arresting flowering b). Deep ploughing c). Puddling d). All of these
Description : Weed eradication is rare but practiced in a). Lantana b). Saccharum sp c). Striga sp d). All of these
Description : A simple perennial weed a). Ipomoea carnea b). Lantana camara c). Both a and b d). None of these
Description : A multi-season annual weed a). Echinochloa colona b). Eclipta alba c). Phyllanthus nirurii d). All of these
Description : Kharif annual weed a). Ammannia bacifera b). Cyperus difformis c). Ludwigia parviflora d). All of these