Number of weed species identified in the  world
a). 30
b). 300
c). 3000
d). 30000

1 Answer

Answer :

d). 30000

Related questions

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Description : Weed species wgich can tolerate so larisation effect a). Phalaris minor b). Sorghum halepense c). Alopecurus myosuroides d). Lolium temulentum

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Description : Factors affecting weed-crop interference are a). Period of weed growth b). Soil and climate influence c). Plant species effects d). All

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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

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Description : If the gross returns from an enterprise are INR 30000 and the net returns INR 20000, the benefit cost ratio based on net gain would be a). 3.0 b). 2.0 c). 1.0 d). 1.5

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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

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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

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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%

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Description : If Echinochloa falls in frequency class ā€˜Eā€™, the weed community is said to be a). Contiguous b). Heterogenous c). Homogenous d). Random

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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%

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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%

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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

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