ICAR JRF Plant Science Practice Series Memory Based 2024 (Module 1) (41 – 80 MCQ) 

 

Question 80

The recommended method for testing the seed germination in mustard is:

1. Sand method
2. Top of paper method
3. Between paper method
4. Wet cloth method

Correct Answer: 3

Explanation: The between paper method provides controlled moisture, aeration, and uniform conditions for small seeds like mustard. It ensures accurate and reproducible germination results, avoiding fungal growth or uneven moisture.

 

 

Question 81

For determining the seed moisture content in the pigeon pea seeds, the seed sample is dried in an oven at a temperature and for a duration of:

1. 103°C for 7 hours
2. 103°C for 4 hours
3. 130°C for 2 hours
4. 130°C for 1 hour

Correct Answer: 4

Explanation: For moisture estimation, pigeon pea seeds are dried at 130°C for 1 hour because they are relatively large and require rapid moisture removal. Higher temperature for shorter time prevents biochemical changes while ensuring accurate moisture determination.

 

 

Question 82

In pea, the maximum permissible size of a seed lot is:

1. 20,000 kg
2. 10,000 kg
3. 5,000 kg
4. 4,000 kg

Correct Answer: 2

Explanation: Limiting seed lot size (10,000 kg for pea) ensures uniformity within the lot, easier sampling, and proper quality control during certification, preventing variation within large seed batches.

 

 

Question 83

Bengal gram is considered as an inseparable other crop plant in the seed production field of the:

1. Green gram
2. Cowpea
3. Oat
4. Lentil

Correct Answer: 4

Explanation: Bengal gram is difficult to separate from lentil due to similar seed size and shape, making it an inseparable contaminant that affects seed purity and certification standards.

 

 

Question 84

Preceding crop requirement is an essential consideration during seed production to minimize the chances of genetic contamination through:

1. Pollen shedders
2. Volunteer plants
3. Objectionable weeds
4. Mutants

Correct Answer: 2

Explanation: Volunteer plants arise from seeds of the previous crop. These plants may carry different genetic traits, leading to genetic contamination in seed production fields. Hence, crop rotation and field history are important.

 

 

Question 85

• Assertion A: Minimum germination standard (%) for the seeds of maize inbred lines is 80%.
• Reason R: Maize hybrid seed should have a minimum of 90% germination.
  Options:

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is NOT the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Correct Answer: 2

Explanation: Maize inbred lines are genetically weak and show lower germination standards (80%), while hybrids are vigorous and require higher standards (90%). However, hybrid standards do not explain why inbreds have lower standards, so both are true but unrelated.

 

 

Question 86

• Assertion A: For moisture estimation by air oven method, fine/coarse grinding of seeds, instead of using whole seeds, is obligatory in some species.
• Reason R: Bigger-sized seeds fail to completely expel all the moisture from the inner tissues during drying, hence grinding becomes necessary.
  Options:

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is NOT the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Correct Answer: 1

Explanation: Large seeds (e.g., maize, pulses) may retain moisture in inner tissues during oven drying. Grinding increases surface area, allowing complete evaporation of moisture. Without grinding, moisture estimation may be underestimated, so the reason correctly explains the assertion.

 

 

Question 87

Match List I with List II (Crop and Inflorescence):

List I (Crop)	List II (Inflorescence)
A. Rice	I. Head or Capitulate
B. Maize	II. Panicle
C. Safflower	III. Arrow
D. Sugarcane	IV. Tassel

Options:

1. A-II, B-III, C-IV, D-I
2. A-II, B-I, C-III, D-IV
3. A-II, B-IV, C-I, D-III
4. A-IV, B-II, C-III, D-I

Correct Answer: 3

• Explanation:
• Rice → panicle (branched inflorescence)
• Maize → tassel (male inflorescence at top)
• Safflower → capitulum (head)
• Sugarcane → arrow (large feathery panicle) These inflorescences are important for pollination biology and breeding practices.

 

 

Question 88

It is said that ‘a clone is immortal’. It means:

1. A clone does not die.
2. A clone can’t be eliminated.
3. The genotype of a clone does not change over time.
4. The performance of a clone does not change with time.

Correct Answer: 3

Explanation: A clone is considered “immortal” because its genetic makeup (genotype) remains unchanged over generations when propagated vegetatively. However, individual plants can die, and performance may vary due to environment.

 

 

Question 89

For notification of variety, the essentially required information are:
A. Identification of the candidate entry by respective coordinated project workshop.
B. Evaluation of the candidate entry in an appropriate coordinated project.
C. Release of the candidate entry by a variety release committee.
D. Distribution of the candidate entry through KVKs.
Options:

1. A, B, and D only
2. A, B, and C only
3. B, C, and D only
4. B and D only

Correct Answer: 2

Explanation: For variety notification:

• Identification through coordinated trials
• Evaluation in multi-location trials
• Official release by variety release committee
  Distribution (D) is not part of the notification process, but comes later.

 

 

Question 90

For the production of certified seeds of hybrid maize, which single cross hybrid seeds will be given to the growers?

1. Breeders seed
2. Foundation seed
3. Certified seed
4. Nucleus seed

Correct Answer: 2 

Explanation: In hybrid maize seed production, farmers are supplied with foundation seed of parental lines to produce certified hybrid seed. (This question is dropped likely due to ambiguity in interpretation.)

 

 

Question 91

‘Normal or substandard seeds’ must satisfy the following requirements to be considered as certified seeds:
A. Genetic purity
B. Physical purity
C. Germination test
D. Freedom from weeds and diseases
Options:

1. A, B, and D only
2. A, B, and C only
3. A, C, and D only
4. B, C, and D only

Correct Answer: DROP 

Explanation: Certified seeds must meet standards of genetic purity, physical purity, germination, and freedom from weeds/diseases. Since the question was dropped, ambiguity likely existed in option combinations.

 

 

Question 92

In some of the following crops, the viability of the seeds is very poor, and hence minimum germination of seeds required for certification is 70% only. The crops are:
A. Rice
B. Hybrid maize
C. Soybean
D. Groundnut
E. Sunflower
Options:

1. A and B only
2. B and C only
3. C and D only
4. D and E only

Correct Answer: 3 

Explanation: Seeds of soybean and groundnut have high oil content, making them prone to rapid deterioration and reduced viability. Therefore, certification allows a lower minimum germination standard (70%).

 

 

Question 93

The steps involved in the utilization of hybrid vigor in maize include:
A. Production of suitable inbred lines
B. Crossing of the selected inbreds in suitable combinations to produce highly productive single cross hybrids
C. Mixing of different single cross hybrid seeds to produce productive double cross hybrids
D. Crossing of the single cross hybrids in suitable combinations to produce highly productive double cross hybrids
Options:

1. A, B, and D only
2. A, B, and C only
3. B, C, and D only
4. B and D only

 

Correct Answer: 1

Explanation:

• Utilization of heterosis in maize involves:
• Developing inbred lines
• Producing single cross hybrids
• Crossing them further to form double cross hybrids
  Mixing seeds is incorrect; proper crossing is required for genetic uniformity.

 

 

Question 94

Match List I with List II (Crop and Objectionable weeds):

List I (Crop)	List II (Objectionable weeds)
A. Rice	I. Wild morning glory
B. Lucerne	II. Mexican prickly poppy
C. Wheat	III. Wild rice
D. Rapeseed and Mustard	IV. Dodder

Options:

1. A-IV, B-III, C-I, D-II
2. A-II, B-IV, C-I, D-III
3. A-III, B-IV, C-II, D-I
4. A-III, B-IV, C-I, D-II

Correct Answer: 4

• Explanation:
• Rice → wild rice (serious contaminant)
• Lucerne → dodder (parasitic weed)
• Wheat → wild morning glory
• Rapeseed & mustard → Mexican prickly poppy. Objectionable weeds are difficult to separate and affect seed purity and certification.

 

 

Question 95

Match List I with List II (Physical/biochemical traits of crop and Insect pests):

List I (Trait)	List II (Insect pest)
A. Hairy leaves	I. Cabbage aphid
B. Saposin content	II. Jassids
C. Sinigrin content	III. Stem sawfly
D. Solid stem	IV. Spotted alfalfa aphid

Options:

1. A-II, B-IV, C-III, D-I
2. A-II, B-IV, C-I, D-III
3. A-III, B-IV, C-I, D-II
4. A-IV, B-II, C-I, D-III

Correct Answer: 2

• Explanation:
• Hairy leaves → reduce feeding of jassids by acting as a physical barrier
• Saponin content → toxic/repellent to spotted alfalfa aphid
• Sinigrin (glucosinolate) → attracts/specialized for cabbage aphid
• Solid stem → prevents larval tunneling of stem sawfly. These traits represent host plant resistance mechanisms (antixenosis & antibiosis).

 

 

Question 96

Assertion A: Atavism refers to the reappearance of a trait after it remains hidden for several generations.
Reason R: The chance combination of genes allows long-suppressed hidden traits to reappear and express.
Options:

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is NOT the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Correct Answer: 1

Explanation: Atavism is the reappearance of ancestral traits after many generations. This happens when recessive or suppressed genes recombine and get expressed due to favorable genetic combinations. Thus, the reason correctly explains the assertion.

 

Question 97

The gene-for-gene relationship between a host and its pathogen was originally proposed by H. H. Flor on the basis of work done on:

1. Leaf rust of wheat
2. Late blight of potato
3. Rust of linseed
4. Wilt of pigeon pea

Correct Answer: 3

Explanation: H. Flor proposed the gene-for-gene relationship based on studies in rust of linseed (flax). He showed that for every resistance gene in host, there is a corresponding avirulence gene in the pathogen.

 

 

Question 98

Potato belongs to the family:

1. Compositae
2. Leguminosae
3. Euphorbiaceae
4. Solanaceae

Correct Answer: 4

Explanation: Solanaceae includes potato along with tomato, brinjal, and tobacco. Members typically have alkaloids and similar floral structures.

 

 

Question 99

Which of the following crops can be inter-cropped with chickpea?
A. Linseed
B. Wheat
C. Rice
D. Mustard
Options:

1. B, C and D only
2. A, C and D only
3. A, B and D only
4. A, B and C only

Correct Answer: 3

Explanation: Chickpea is a rabi crop, so it is intercropped with crops like linseed, wheat, and mustard that share similar season and resource requirements. Rice is a kharif crop, so it is not suitable.

 

 

Question 100

Late blight of potato is caused by:

1. Phytophthora infestans
2. Alternaria solani
3. Erwinia carotovora
4. Pythium aphanidermatum

Correct Answer: 1

Explanation: Late blight of potato is caused by Phytophthora infestans, an oomycete that thrives in cool, moist conditions and caused the historic Irish potato famine.

 

 

Question 101

Which of the following are two cultivated species of cotton used for spinnable fibre?
A. Gossypium hirsutum
B. Gossypium raimondii
C. Gossypium barbadense
D. Gossypium thurberi
Options:

1. B and D only
2. A and B only
3. B and C only
4. A and C only

Correct Answer: 4

Explanation: The two major cultivated cotton species for fibre are:

• Gossypium hirsutum (upland cotton, most widely grown)
• Gossypium barbadense (Egyptian cotton, superior fibre quality)
  Other species are wild or not used commercially.

 

 

Question 102

Statement I: Traditionally Indian soils are divided into four major groups.
Statement II: The Indian land surface is predominantly covered with red soils followed by black soils.
Options:

1. Both Statement I and Statement II are true
2. Both Statement I and Statement II are false
3. Statement I is true but Statement II is false
4. Statement I is false but Statement II is true

Correct Answer: 3

Explanation: Traditionally, Indian soils are divided into more than four types (alluvial, black, red, laterite, desert, etc.), so Statement I is incorrect. However, red soils cover the largest area, followed by black soils, making Statement II correct.

 

 

Question 103

Match List I with List II:

List I	List II
I. National Rural Livelihoods Mission (NRLM)	A. Improving land productivity
II. Integrated Watershed Management Programme (IWMP)	B. Housing to BPL households
III. Pradhan Mantri Awaas Yojana – Grameen (PMAY-G)	C. Providing wage employment
IV. Mahatma Gandhi National Rural Employment Guarantee Act (MGNREGA)	D. Self-employment and skill development

Options:

1. I-A, II-D, III-C, IV-B
2. I-B, II-A, III-D, IV-C
3. I-D, II-A, III-B, IV-C
4. I-B, II-D, III-C, IV-A

Correct Answer: 3

• Explanation:
• NRLM → self-employment & skill development
• IWMP → improving land productivity & watershed management
• PMAY-G → housing for rural poor (BPL households)
• MGNREGA → wage employment guarantee These schemes address different aspects of rural development and livelihood security.

 

 

Question 104

Arrange the following in the order of their coming into existence:
A. Protection of Plant Varieties and Farmers’ Right Act (PPV&FR Act)
B. Convention on Biological Diversity
C. The Indian Patents Act
D. International Convention of the Union for Protection of New Varieties of Plants (UPOV)
Options:

1. D, C, B, A
2. B, A, D, C
3. C, D, B, A
4. A, B, C, D

Correct Answer: 3

Explanation:

• Correct chronological order:
• The Indian Patents Act (1970)
• UPOV Convention (1961, but adopted later in India context)
• Convention on Biological Diversity
• PPV&FR Act
  Thus, logically in Indian context: C → D → B → A, showing evolution from patent protection to biodiversity and farmers’ rights.

 

 

Question 105

Which of the following Geographical Indication is not matched correctly?

1. Kandhamal Haladi – Odisha
2. Kala Zeera – Jammu & Kashmir
3. Darjeeling tea – West Bengal
4. Tezpur Litchi – Assam

Correct Answer: 2 

Explanation: Kala Zeera GI is mainly associated with Himachal Pradesh, not Jammu & Kashmir. Other options are correctly matched, so option 2 is incorrect.

 

 

Question 106

Arrange in descending order the following soil types of India according to their area of predominance:
A. Alluvial soils
B. Red soils
C. Laterite soils
D. Black soils
Options:

1. C, A, B, D
2. A, C, B, D
3. D, B, C, A
4. B, D, A, C

Correct Answer: DROP 

Explanation:

• The correct order should be:
• Alluvial > Red > Black > Laterite soils (area-wise).
• The question was dropped likely due to ambiguity in options, but conceptually alluvial soils cover the largest area in India.

 

 

Question 107

Assertion A: Inbreeding depression is the reduced survival and fertility of offspring of related individuals.
Reason R: Inbreeding increases heterozygosity exposing harmful recessive alleles in homozygotes.
Options:

1. Both A and R are true and R is the correct explanation of A
2. Both A and R are true but R is NOT the correct explanation of A
3. A is true but R is false
4. A is false but R is true

Correct Answer: 3 

Explanation: Inbreeding increases homozygosity, not heterozygosity. This exposes deleterious recessive alleles, leading to reduced vigor, fertility, and survival (inbreeding depression). Hence Assertion is correct, but Reason is incorrect.

 

 

Question 108

Assertion A: ICAR-Indian Institute of Sugarcane Research is located at Coimbatore.
Reason R: ICAR-National Bureau of Plant Genetic Resources is located at New Delhi.
Options:

1. Both A and R are true and R is the correct explanation of A
2. Both A and R are true but R is NOT the correct explanation of A
3. A is true but R is false
4. A is false but R is true

Correct Answer: 4

Explanation: ICAR-Indian Institute of Sugarcane Research is located in Lucknow, not Coimbatore → Assertion is false.
National Bureau of Plant Genetic Resources is correctly located → Reason is true.

 

 

Question 109

Prime Minister of India released 35 varieties of different crops in September 2021, which were developed by various institutes under ICAR, State & Central Agricultural Universities and Krishi Vigyan Kendras. The main aim was to create mass awareness for the adoption of climate-resilient technologies. The list of these 35 varieties includes the following crops:

1. Pigeon pea and Chickpea
2. Sunflower and safflower
3. Brinjal and tomato
4. Black gram and green gram

Correct Answer: 1

Explanation: The release of 35 climate-resilient varieties focused mainly on pulse crops like pigeon pea and chickpea, which are important for nutritional security and climate adaptability.

 

 

Question 110

Assertion A: CAM plants are present in dry and arid environments.
Reason R: The CAM pathway is adapted to minimize water loss and photorespiration.
Options:

1. Both A and R are correct and R is the correct explanation of A
2. Both A and R are correct but R is NOT the correct explanation of A
3. A is correct but R is not correct
4. A is not correct but R is correct

Correct Answer: 1

Explanation: CAM plants (e.g., cactus) are adapted to arid environments. They open stomata at night to fix CO₂, reducing water loss and photorespiration. Thus, the reason correctly explains the assertion.

 

 

Question 111

Which one is incorrect with respect to transpiration in plants?

1. Flow of mineral nutrients and water through xylem
2. Diffusion of carbon dioxide from the air for photosynthesis
3. Change in osmotic pressure of cells
4. Reduction of cooling effect on the leaf surface

Explanation: Correct Answer: 4 

Transpiration provides a cooling effect through evaporation. Option 4 states the opposite (reduction of cooling), which is incorrect. Other options relate indirectly to plant water relations.

 

 

Question 112

Assertion A: Dioecy ensures that outbreeding will always occur.
Reason R: In dioecy, male and female flowers are present on different parts of the same plant.
Options:

1. Both A and R are correct and R is the correct explanation of A
2. Both A and R are correct but R is NOT the correct explanation of A
3. A is correct but R is not correct
4. A is not correct but R is correct

Correct Answer: 3 (R is false; in dioecy, male and female flowers are on different plants, not different parts of same plant)

Explanation:  Dioecy means male and female flowers occur on separate plants, ensuring cross-pollination (outbreeding). The reason is incorrect because it describes monoecy, not dioecy.

 

 

Question 113

Arrange the following parts of Wheat (Triticum aestivum L.) in descending order with respect to their chromosome number:
A. Endosperm
B. Male gamete
C. Embryo
Options:

1. B, A, C
2. C, A, B
3. A, C, B
4. A, B, C

Correct Answer: 3 

Explanation:

• In wheat (hexaploid, 2n = 42):
• Endosperm = 3n = 21 (formed after double fertilization)
• Embryo = 2n = 14 (zygote)
• Male gamete = n = 7
  Thus descending order: Endosperm > Embryo > Male gamete (A, C, B). This reflects ploidy differences during fertilization.

 

 

Question 114

Which of the following amino acid starts all protein synthesis?

1. Glycine
2. Methionine
3. Thymine
4. Proline

Correct Answer: 2

Explanation: Protein synthesis starts with methionine (AUG start codon) in eukaryotes. In prokaryotes, it is modified as formyl-methionine (fMet), but methionine remains the initiating amino acid.

 

 

Question 115 

Assertion A: DNA polymerase can synthesize DNA in the 5′ to 3′ direction.
Reason R: DNA polymerase can synthesize DNA in the 3′ to 5′ direction.
Options:

1. Both A and R are true and R is the correct explanation of A
2. Both A and R are true but R is NOT the correct explanation of A
3. A is true but R is false
4. A is false but R is true

Correct Answer: 3 

Explanation: DNA polymerase synthesizes DNA only in 5′ → 3′ direction by adding nucleotides to the 3′-OH end. It cannot synthesize in 3′ → 5′ direction, so the reason is false while assertion is true.

 

 

Question 116

Assertion A: The mode of DNA replication is semi-conservative in nature.
Reason R: One of the DNA strands is synthesized continuously, while the other is synthesized discontinuously.
Options:

1. Both A and R are correct and R is the correct explanation of A
2. Both A and R are correct but R is NOT the correct explanation of A
3. A is correct but R is not correct
4. A is not correct but R is correct

Correct Answer: 2 

Explanation: Semi-conservative replication means each daughter DNA has one parental strand and one newly synthesized strand.
The reason describes semi-discontinuous replication (leading and lagging strands), which is a different concept. Hence both are true but unrelated.

 

 

Question 117

In molecular marker technologies, the acronym RFLP stands for:

1. Random Fragment Locus Polymorphism
2. Random Fragment Length Polymorphism
3. Restriction Fragment Locus Polymorphism
4. Restriction Fragment Length Polymorphism

Correct Answer: 4

Explanation: RFLP = Restriction Fragment Length Polymorphism, a molecular marker technique based on differences in DNA fragment lengths after restriction enzyme digestion, useful in genetic mapping and diversity studies.

 

Question 118

The inflorescence of rice is called:

1. Ear
2. Panicle
3. Spike
4. Spadix

Correct Answer: 2

Explanation:  Rice has a panicle inflorescence, which is a branched structure bearing multiple spikelets. This is important for yield components like number of grains per panicle.

 

 

Question 119

Assertion A: India is the largest producer of potato in the world.
Reason R: The states Uttar Pradesh, West Bengal and Punjab account for majority of potato production in India.
Options:

1. Both A and R are true and R is the correct explanation of A
2. Both A and R are true but R is NOT the correct explanation of A
3. A is true but R is false
4. A is false but R is true

Correct Answer: 4 (China is the largest producer of potato in the world, not India)

Explanation:  India is not the largest potato producer (China is). However, states like Uttar Pradesh, West Bengal, and Punjab contribute majorly to Indian production. Thus Assertion is false, Reason is true.

 

Question 120

Arrange the following classes of seeds in ascending order of their genetic purity percentage:
A. Certified seed
B. Breeder seed
C. Foundation seed
D. Nucleus seed
Options:

1. D, C, A, B
2. A, C, B, D
3. C, A, B, D
4. A, B, C, D

Correct Answer: 2 (Ascending: Certified < Foundation < Breeder < Nucleus)

Explanation:

• Seed classes in increasing genetic purity:
• Certified seed (lowest)
• Foundation seed
• Breeder seed
• Nucleus seed (highest purity)
  This hierarchy ensures maintenance of genetic identity and quality in seed production systems.