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 : . A shortest time span in the life cycle of a crop when weeding results in highest eco nomic returns a). Economic threshold b). Critical period c). Competitive threshold d). None of these
Last Answer : b). Critical period
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 competitive crop requiring weed free period of about 3-4 weeks a). Soybean b). Carrot c). Garlic d). Onion
Last Answer : a). Soybean
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 : 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 : The producer usually is most concerned about the a). Competitive threshold b). Economic threshold c). Both a and b d). None of the above
Last Answer : b). Economic threshold
Description : Integrated weed management practices that a). Enhance crop competitive ability b). Decrease weeds ability to reduce yield c). Practices that eliminate weeds from an area d). Both a and b e). Both a and c
Last Answer : d). Both a and b
Description : Competitive crops such as corn or soybean require weed-free period of a). 2 months b). 3-4 weeks c). 3 months d). None of the above
Last Answer : b). 3-4 weeks
Description : Factors affecting weed-crop interference are a). Period of weed growth b). Soil and climate influence c). Plant species effects d). All
Last Answer : d). All
Description : Intra-specific competition is between a). Plants of the cultivated species and weed species b). Plants of the same weed species c). Plants of the different weed species d). None of the above
Last Answer : b). Plants of the same weed species
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 : 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 : The effective solution to manage weed shifts a). Herbicide combinations b). Herbicide rotations c). Crop rotations d). All
Description : November sown berseem crop induces the weed a). Chenopodium sp b). Anagallis sp c). Vicia sp d). All of these
Last Answer : d). All of these
Description : The official peer-reviewed Journal of the EWRS (European Weed Research Society) is a). Journal of Crop and Weed b). Weed Research c). Weed Science
Last Answer : b). Weed Research
Description : Struggle for survival and existence is called a). Critical period b). Competition c). Dormancy d). Persistence
Last Answer : b). Competition
Description : Noncompetitive crops such as onion or garlic require a weed-free period of a). 3 months or more b). One month c).10 days d). None of the above
Last Answer : a). 3 months or more
Description : What is the Critical Period of Crop-Weed Competition for sugarcane?
Last Answer : Ans.30-120 DAS
Description : What is the Critical Period of Crop-Weed Competition for Upland rice condition?
Last Answer : Ans.Entire period of crop growth
Description : What is the Critical Period of Crop-Weed Competition for transplanted rice?
Last Answer : Ans.30-45 DAS
Description : Competitive ability of the crops in decreas ing order a). barley>rye>wheat >oats b). oats>wheat> rye> barley c). rye>barley>oats> wheat d).wheat>oats>barley >rye
Last Answer : a). barley>rye>wheat >oats
Description : The striving of two or more individuals for the same object a). Allelopathy b). Competition c). Co-operation d). None of these
Description : The ecological phenomenon of plant-plant interference a). Competition b). Allelopathy c). Both d). None
Last Answer : c). Both
Description : Weed move from its origin to new environ ment is called a). Introduced weed b). Alien weed c). Antrophytes d). All of these
Last Answer : b). Alien weed
Description : If Echinochloa falls in frequency class āEā, the weed community is said to be a). Contiguous b). Heterogenous c). Homogenous d). Random
Last Answer : c). Homogenous
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 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 : 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 : 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 : 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 : 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