Weed Management Test 2 — Agri Master Mind
Which of the following causes itching and inflammation
- Ammannia baccifera
- Solanum nigrum
- Urtica sp
- Lantana camara
A system approach based on whole land use planning
- Weed eradication
- Weed control
- Weed prevention
- None
The first rule of weed prevention
- Regular survey to identify new weeds
- Destruction of weeds before they set seed
- Clean farm equipments and irrigation water
- Clean seed
A herbicide requiring good spray coverage of all foliage for effective control of a weed population
- Paraquat
- Glyphosate
- Atrazine
- Isoproturon
A weed accumulate over 550 ppm of Zn in its dry matter
- Digitaria
- Setaria lutescens
- Portulaca
- Chenopodium
A period in the ontogeny of crop at which maximum crop weed competition occurs is called
- Economic threshold
- Gain threshold
- Competitive threshold
- None
A non-competitive crop requiring weed free period of three or more months
- Maize
- Rice
- Soybean
- Onion
Selectivity achieved due to changes in functional group is called
- Physical
- Biological
- Chemical
- Chronological
Herbicide antidote interactions are
- synergistic
- antagonistic
- Enhancement
- None of these
Through wetting of all foliage is unnecessary with which of the following
- glyphosate
- paraquat
- diquat
- None of these
Application of organophosphorus group of pesticides along with which herbicides cause injury to crops
- Triazines
- Ureas
- Both
- None
The term, allelopathy came into existence in
- 1937 AD
- 500 BC
- 1974 AD
- 1832 AD
Epinasty of cotton is used to measure qualitative assay of
- Atrazine
- 2,4-D
- Diuron
- Alachlor
In india herbicides are registered under which of the following Act
- Herbicide Registration Act
- Insecticide Act, 1968
- Environment Policy, 2005
- Indian Agrochemicals Registration
A test method using organism to determine the presence of herbicide effect is
- Cucumber
- Sorghum
- Oat
- All
Critical period of crop weed competition in sugarcane is
- 30-40 days
- 30-120 days
- 10-40 days
- 15-30 days
One to two flushes of weeds are destroyed before planting of crop is called
- Stale seed bed
- Blind hoeing
- Weeding
- Summer ploughing
Which herbicide group inhibitor the photosynthesis reaction ?
- Thiocarbamates
- Triazines
- Cyclohexanedione
- Benzoic acid
Change in molecular structure of applied herbicides inside the plant is known as
- Conjugation
- Metabolism
- Reverse metabolism
- Degradatio
Which herbicide’s mode of action is root growth inhibition?
- Fluchloralin
- MCPA
- Glyphosate
- Alachlor
VELGO is a bioherbicide used against
- Echinochloa
- Parthenium
- Cenchrus
- Abutilon
Environmental factors which increases the allelopathic effects are
- low soil fertility
- Warm wet condition
- Cold wet conditions
- a and b
An approach where bio-herbicides are used to control indigenous weed species
- Inundative approach
- Inoculative approach
- Classical approach
- None of the above
A post-emergence herbicide in Soybean
- Pendimethalin 1.2 kg/ha
- Quazalofop – ethyl 60 g/ha
- Fluchloralin 0.9 kg/ha
- Thiobencarb 1.50 kg/ha
A nitrogen fixing weed species in wheat
- Lathyrus aphaca
- Medicago denticulata
- Vicia sativa
- All
Scheme for testing the field performance of herbicides in rice, wheat and sugarcane in different states of India by ICAR was initiated in
- 1948
- 1952
- 1956
- 1960
Indian Society of Weed Science was founded in
- 1958
- 1968
- 1989
- 1997
Herbicide effectively controls Saccharum and Sorghum halepense only at preflowering stage
- Diuron
- Atrazine
- Amitrole
- Both a and c
If weed population is 70/m2 and the crop 140/m2, weed intensity would be
- 33.3%
- 66.6%
- 50%
- 73.4%
If the yield from weed free is 3500 kg and that from weedy 1500 kg/ha, weed index would be
- 57.1%
- 133.3%
- 45.0%
- 25.6%
If the count of Echinochloa in weedy check is 70 and that in a treatment 25/m2, weed control efficiency will be
- 54.3%
- 64.3%
- 73.4%
- 79.6%
Dryland weeds usually have
- deep root
- hairyness
- Mucilaginous stem
- all
The most systematic method for classifying weeds is based on
- Morphology
- Life history
- Habitat
- Phylogenetic
Successful weed management is based on a). Knowledge on weed biology b). Survey on the nature of weed problem c). Whole farm planning d). Removal of weeds before flowering
- a & b
- b & d
- c & d
- All
Which herbicide is used in aquatic weed control?
- Acrolein
- Delapon
- Diuron
- Picloram
An ingredient added to a formulation for enhancing the action of toxicant is Called
- Adsorbent
- Adjuvant
- Antidote
- None
Change in molecular structure of applied herbicides inside the plant is known as
- Conjugation
- Metabolism
- Reverse metabolism
- Degradation
Which of the plants will show more susceptibility to herbicide application?
- Stressed
- Healthy
- Old
- all
Metsulfron herbicide belong to which group
- Sulfonylureos
- Pyridines
- Benzoic
- Carboxalic group
The weather condition is optimum for herbicidal weed control?
- High temperature low humidity
- High temperature high humidity
- warm temperature high humidity
- cold temperature low humidity
Which type of clay will adsorb more herbicide?
- Montmorillonite
- Illite
- Kaolinite
- b & c
Oxadiazon has a half life of 60 days, so after 120 days the concentration will be
- ½
- ¼
- 1/3
- 1/5
Drift susceptible size of droplets in micron diameter is
- 150-200
- 200-250
- <150
- >250
The first genetically modified plants, the soybean resistant to glyphosate was developed durin
- 1983
- 2003
- 1993
- 1973
A application method to avoid herbicide drift
- Misting
- Wick wiping
- Foliar spray
- Basal barking
The most imprecise way of herbicide application
- Misting
- Aerial spraying
- Foliar spray
- Basal barking
The process by which a molecule is discovered, developed and formulated into a pesticide product is
- Tenuous and risky
- Mimic
- Both
- None
Which are required during trialling to ensure that the effectiveness of the herbicide is tested against all pests
- Plant pathologists
- Entomologists
- Both Plant pathologists and Entomologists
- None
To prepare soils for the bioassay, herbicides get inactivated by
- Darco G-60
- Activated charcoal
- a & b
- None
Weed control index if weed dry weight of a treatment is 200 g/m2 and that of weed check was 600 g/m2
- 33.3%
- 66.7%
- 25%
- None of these
Directorate of Weed Research is situated at
- Jabalpur
- Karnal
- Jhansi
- Navsari
The Asian Pacific Weed Science Society (APWSS) was founded in
- 1667
- 1985
- 1951
- 1992
National Research Centre for Weed Science (NRCWS), now Directorate of Weed Research (DWR) Jabalpur came into existence on
- 22 April,1982
- 22 April,1985
- 22 April, 1989
- 22 April, 1997
2,4-D was first tested in India in
- 1950
- 1946
- 1943
- 1942
The international Weed Science Society (IWSS) was formed in
- 1955
- 1968
- 1975
- 1985
When NRCWS Jabalpur was upgraded to Directorate of Weed Science Research (DWSR)
- 2005
- 2009
- 2011
- 2014
A widely used pre-plant herbicide in conservation agricultural systems
- Pendimethalin
- Trifluralin
- Glyphosate
- Fluchloralin
The weed propagated through rhizomes/root stock
- Agropyron repens
- Cynodon dactylon
- Typha angustata
- All of these
Weed move from its origin to new environment is called
- Introduced weed
- Alien weed
- Antrophytes
- All of these
A dominant weed of puddle paddy soil
- Echinochloa
- Caesulina
- Eclipta sp
- All of these
Herbicide deactivation of selectivity in plants is achieved by
- Herbicide metabolism
- Herbicide conjugation
- Both a and b
- None of these
Typically pre-plant soil incorporated herbicide
- Fluchloralin
- Trifluralin
- EPTC
- All of these
A broad-spectrum herbicide in groundnut
- Fluchloralin
- Atrazine
- Alachlor
- 2,4-D
A shortest time span in the life cycle of a crop when weeding results in highest economic returns
- Economic threshold
- Critical period
- Competitive threshold
- None of these
The crops known for autotoxicity
- Lucerne and wheat
- Berseem and oats
- Rice and soybeans
- None of these
A rectangular hyperbolic relationship between weed density and crop yield is proposed by
- Roberts and Bonds (1975)
- Cousens et al (1984&1985)
- Zimdahl 1980
- None of these
A curvilinear relationship between weed density and crop yield was reported by
- Zimdahl 1980
- Roberts and Bonds (1975)
- Cousens et al (1985)
- None of these
Dehalogenation is the most common inactivation reaction in which of the following
- Simazine
- Glyphosate
- Pendimethalin
- Bispyribac
To control broad-leaved weeds in barley, which of the herbicide is most suitable
- 2,4-D
- Metsulfuron
- Alachlor
- Both a and b
A selectivity achieved due to manipulation of time of application is called
- Biochemical
- Chronological
- Chemical
- Physical
Post-plant tillage helps in
- Mixing of manures
- Control of weeds
- Soil and water conservation
- None
Practices using direct radiant energy of the sun
- Soil solarization
- Micro-waves
- Flaming
- All
Bioagent for controlling Parthenium hysterophorus
- Bactra verutana
- Zygogramma bicolorata
- Chrysolira
- Flea beetle
Integrated weed management practices that
- Enhance crop competitive ability
- Decrease weeds ability to reduce yield
- Practices that eliminate weeds from an area
- Both a and b
The herbicidal activity of 2,4-D at the first time was reported by
- Hammer and Tukey (1944)
- Zimmernam and Hitchcock (1942)
- Nutman and Blackman (1945)
- None
In case of combined application of herbicides, application rate can be reduced in which of the following interaction
- Antagonistic
- Synergistic
- Additive
- None
Generally weeds seeds are abundant at a depth of
- 1.0-1.5cm
- 5 cm
- 10cm
- 15cm
Active toxic material present in the formulation is
- Acid equivalent
- Phytochemical
- Active ingredient
- Surfactant
Production practices that influence weed shift are
- Effectiveness of weed management program
- Interface areas
- Speed of weed shift occurrence
- All
Trade name of Nitrofen ?
- Lasso
- Toke - E - 25
- Round up
- Plant guard
The mode of action of Atrazine is
- Pigment inhibition
- Cell membrane disruption
- Seedling growth inhibition
- Photosynthesis inhibition
Herbicides prone to photodecomposition such as Trifluralin, monuron, chloramben and PCP should be applied in
- Morning
- Evening
- Afternoon
- All
Montmorillonite clays adsorb more herbicide as compared to other clays due to
- Expanding lattices
- more surface area
- More negatively charged sites
- All
Paraquat herbicide belong to which group
- Bipyridylium
- Benzoic
- Carboxalic
- Uraciles
The authority associated with the first genetically modified plants the soybean resistant to glyphosate from Monsanto which achieved widespread success was
- Rachel Carson (May 27, 1907 – April 14, 1964)
- Fritz Haber (9 December 1868 – 29 January 1934)
- Robert Fraley (birthdate: 1953)
- Norman Borlaug (March 25, 1914 – September 12, 2009)
The first genetically modified plants, the soybean resistant to glyphosate was developed during
- 1983
- 2003
- 1993
- 1973
Bromoxynil (Bxn) is resistant trait of which crop
- Soybean
- Sugarbeet
- Maize
- Cotton
Which of these is not a broad spectrum herbicide
- Atrazine
- Paraquat
- Bromoxynil
- Glyphosate
First mycoherbicide developed by Abbott Laboratories, USA was
- Biosedge
- Devine
- Collego
- Biomal
Continuous cropping of which legume crop cause auto allelopathy?
- Chickpea
- Alfa-alfa
- Cowpea
- Pigeonpea
Classical strategy of biological approach involves
- Biocontrol agent
- Bioherbicides
- Bio assay
- a & b
Which among the following bioherbicide has control efficiency more than 90 per cent?
- Collego
- Devine
- CASST
- Biomal
A test method using organism to determine the presence of herbicide effect is
- Herbicide analysis
- Bio assay
- Bio control
- None of these
If 1.35 kg/ha of fluchloralin is to be applied, Basalin 45 SL required is
- 3 litre
- 2 litre
- 1.35 litre
- 2.7 litre
Amount of Topic 10% for 4000 m2 if rate of clodinafop is 60 g/ha.
- 600 g
- 480 g
- 300 g
- 240 g
Amount of 2,4-D amine salt at 10 ppm for a pond measuring 40mx20mx5m
- 0.4 kg
- 400 kg
- 40 kg
- 4 kg
Amount of Alachlor 50% EC for spraying 12 ha maize field (given the dose 1.5 kg ai/ha)
- 36 kg
- 18 kg
- 54 kg
- 12 kg
Number of weed species identified in the world
- 30
- 300
- 3000
- 30000
Most dominant factor influencing weed composition in a field is
- Soil moisture
- Soil type
- Soil texture
- Soil temperature
Reverse metabolism induce the susceptibility to weeds by
- 2,4-D
- MCPA
- Both a and b
- None of these
First introduced organic herbicide in the world is
- Dinoseb
- 2,4-D
- MCPA
- All of these