DAY – 24 : Insta 75 Days Revision Plan-2026 : AGRICULTURE

Answer: (a)

Explanation

Statement I is correct: Hydroponics is a method of growing plants without the use of soil. Instead of soil, plants are supported using inert media such as coco peat, perlite, or rock wool, or sometimes suspended directly in nutrient-rich water. The absence of soil distinguishes hydroponics from conventional agriculture and allows cultivation in areas with poor or no soil availability.

Statement II is correct: In hydroponic systems, plants receive essential nutrients through a water-based solution that is carefully formulated to include macro- and micronutrients such as nitrogen, phosphorus, potassium, calcium, and trace elements. This nutrient solution is delivered directly to the plant roots, ensuring precise control over nutrient availability, leading to efficient uptake and often faster growth compared to soil-based systems.

Statement III is incorrect: Hydroponics does not require natural soil microbes for nutrient uptake. In traditional soil-based agriculture, microbes play a crucial role in decomposing organic matter and making nutrients available to plants. However, in hydroponics, nutrients are already provided in a soluble and readily absorbable form, eliminating the need for microbial mediation. While some advanced hydroponic systems may incorporate beneficial microbes to enhance plant health, their presence is not essential for nutrient uptake.

Answer: (a)

Explanation:

Statement I is correct: Precision phenotyping involves high-throughput and accurate measurement of plant traits using advanced, non-invasive technologies such as imaging sensors, drones, and automated platforms. These tools enable continuous monitoring of plant growth, physiology, and stress responses without damaging the plant.

Statement II is correct: It plays a crucial role in crop improvement by helping identify desirable traits such as drought tolerance, pest resistance, and nutrient efficiency. This accelerates the selection of superior crop varieties in breeding programs.

Statement III is incorrect: Precision phenotyping minimizes reliance on manual visual inspection. Traditional methods were dependent on human observation, which is subjective and time-consuming. In contrast, precision phenotyping uses automated, sensor-based, and data-driven approaches, enhancing accuracy and scalability rather than depending on manual inspection.

Statement IV is correct: It is a key enabler of climate-smart agriculture, as it helps develop crop varieties that can withstand climate stresses such as heat, drought, and salinity. By speeding up breeding cycles, it contributes significantly to agricultural sustainability and resilience.

Answer: (b)

Explanation:

‘Bijamrita’, ‘Jivamrita’, and ‘Acchadana’ are key components of Zero Budget Natural Farming (ZBNF), a sustainable agricultural approach promoted in India, notably by Subhash Palekar. These terms represent core practices aimed at reducing dependence on chemical inputs and enhancing soil health.

• Bijamrita: A natural seed treatment formulation made from cow dung, cow urine, lime, and soil. It protects seeds from pathogens and promotes healthy germination.
• Jivamrita: A microbial culture prepared using cow dung, urine, jaggery, pulse flour, and soil. It acts as a bio-fertilizer, enhancing soil microbial activity and nutrient availability.
• Acchadana (Mulching): It involves covering the soil with organic matter such as crop residues to conserve moisture, regulate soil temperature, and improve soil fertility.

These, along with Whapasa (soil aeration and moisture management), constitute the four pillars of ZBNF.

Answer: (a)

Explanation:

Statement I is correct: Vertical farming enables year-round crop production by cultivating plants in stacked layers within indoor environments. Since it is not dependent on natural climatic conditions, it eliminates the constraints imposed by seasonal variations such as temperature fluctuations, rainfall variability, and extreme weather events.

Statement II is correct: Controlled Environment Agriculture (CEA) involves the use of technology to precisely regulate environmental parameters such as light (using LED systems), temperature, humidity, carbon dioxide levels, and nutrient delivery. This creates optimal growing conditions tailored to specific crops.

Answer: (d)

Explanation:

Pair I is correct: The Phad system is a traditional community-managed irrigation system practiced in Maharashtra, particularly in the Tapi basin. It involves diversion of river water through canals with equitable water distribution among farmers.

Pair II is correct: The Zabo system is an indigenous water management practice found in Nagaland. It integrates water harvesting, forestry, agriculture, and animal husbandry in a sustainable hill ecosystem.

Pair III is correct: The Ahar-Pyne system is a traditional floodwater harvesting and irrigation system prevalent in Bihar, especially in the south Bihar plains. ‘Ahar’ refers to reservoirs, while ‘Pyne’ are channels that distribute water.

Pair IV is correct: The Surangam system is a horizontal tunnel-based irrigation technique practiced in the laterite regions of Kerala and parts of Karnataka. It taps groundwater through horizontal wells.

Answer: (b)

Explanation:

Statement I is incorrect: Speed breeding uses controlled environmental conditions such as extended light exposure (long photoperiod), optimized temperature, and humidity to accelerate plant growth. It increases, rather than shortens, the photoperiod to speed up developmental stages like flowering.

Statement II is correct: Speed breeding can significantly reduce generation time, allowing up to 5–6 generations of crops like wheat and barley to be grown in a single year under controlled conditions. This greatly accelerates crop improvement programs.

Statement III is incorrect: Speed breeding is not limited to C4 crops. It has been successfully applied to several C3 crops such as wheat, barley, chickpea, and canola. Its applicability depends on the ability to manipulate environmental conditions, not on the photosynthetic pathway of the plant.

Answer: (c)

Explanation:

Statement I (CRISPR-Cas9) is correct: It is a programmable genome-editing tool that uses a guide RNA and Cas9 nuclease to create precise double-stranded breaks at specific DNA sequences. It is classified as a Site-Directed Nuclease (SDN).

Statement II (TALENs) is correct: Transcription Activator-Like Effector Nucleases consist of customizable DNA-binding domains fused to a nuclease (FokI). They introduce targeted DNA breaks and are classic SDN tools.

Statement III (ZFNs) is correct: Zinc Finger Nucleases are engineered proteins combining zinc-finger DNA-binding domains with a nuclease domain to induce site-specific DNA cleavage. They are among the earliest SDN technologies.

Statement IV (Agrobacterium-mediated transformation) is incorrect: This is a method of gene transfer used to insert foreign DNA into plant genomes via the bacterium Agrobacterium tumefaciens. It is not a nuclease-based genome editing tool and hence not categorized as an SDN.

Answer: (c)

Explanation:

Statement I is correct: Agroforestry, which integrates trees with crops and/or livestock, enhances ecological sustainability while providing multiple income streams such as timber, fruits, fodder, and fuelwood, thereby diversifying farmer income.

Statement II is correct: Integration of trees with crops improves soil fertility through processes such as nitrogen fixation (in case of leguminous trees), litter fall, and improved soil structure. It also enhances carbon sequestration by storing carbon in biomass and soil, thereby contributing to climate change mitigation. This directly explains the ecological sustainability aspect mentioned in Statement I.

Statement III is incorrect: Agroforestry generally enhances resilience to climate variability rather than reducing it. Trees act as windbreaks, improve microclimatic conditions, reduce soil erosion, and enhance water retention. While there may be some competition for resources, well-designed agroforestry systems optimize complementarities rather than reduce resilience.

Answer: (b)

Explanation:

Statement I is correct: Kisan Call Centres (KCC) are an important agri-extension initiative in India that provide real-time advisory services to farmers in multiple regional languages. With increasing digitisation, elements of technologies such as Natural Language Processing (NLP) are being integrated to improve language accessibility, voice-based interaction, and contextual advisory delivery, especially in diverse linguistic settings.

Statement II is correct: The Farmer FIRST (Farmer’s Farm, Innovations, Resources, Science and Technology) programme, implemented by ICAR, adopts a farmer-centric approach where farmers are treated as active collaborators in the research and innovation process. It emphasizes participatory technology development, validation, and dissemination.

Answer: (a)

Explanation:

Statement I is correct: Tea cultivation in the Nilgiri hills of the Western Ghats is typically carried out at elevations ranging from about 1,000 to 2,500 metres above sea level. These high-altitude conditions, along with cool temperatures and high humidity, are ideal for producing the distinctive flavour and aroma associated with Nilgiri tea.

Statement II is incorrect: Tea plants require well-drained, acidic soils such as lateritic or loamy soils rich in organic matter. While moisture retention is important, excessive water retention—as seen in heavy alluvial loam soils—can lead to waterlogging, which is unsuitable for tea cultivation. Hence, alluvial loam soils with high water retention are not considered most suitable for tea in the Nilgiris.

Answer: (c)

Solution:

Given:

Number of persons = 8

Increase in average = 2.5 kg

Step 1: Increase in total weight

Increase = 8 × 2.5 = 20 kg

Step 2: Replacement concept

New person replaces 65 kg person

So,

New weight − 65 = 20

Step 3: Final value

New weight = 65 + 20 = 85 kg

Answer: (b)

Solution:

Given:

Total students = 60

Overall average = 50

Passed avg = 60

Failed avg = 30

Method 1: Alligation

Passed : Failed

= (50 − 30) : (60 − 50)

= 20 : 10

= 2 : 1

Total parts = 3

Passed = (2/3) × 60 = 40

Method 2: Direct Equation

Total marks = 60 × 50 = 3000

Let passed students = x

Failed = 60 − x

Total marks =

60x + 30(60 − x) = 3000

60x + 1800 − 30x = 3000

30x = 1200

x = 40

Answer: (c)

Solution:

Total sum of 11 numbers = 11 × 60 = 660

Sum of first 6 = 6 × 58 = 348

Sum of last 6 = 6 × 63 = 378

Combined sum = 348 + 378 = 726

6th number counted twice

6th number = 726 − 660 = 66

Answer: (b)

Solution:

Given:

Average = 45

Step 1: Total sum

x + y + z = 135

Step 2: Condition

x − 45 = 45 − y

So,

x + y = 90

Step 3: Substitute

90 + z = 135

z = 45

Answer: (b)

Explanation:

The passage highlights an imbalance in India’s growth pattern where the service sector contributes significantly to GDP but cannot absorb large numbers of unskilled workers due to its requirement for higher education and technical skills. This creates a situation where economic growth does not translate into proportional job creation, known as jobless growth. Skilled individuals benefit more, while unskilled workers face limited opportunities. Over time, this gap widens economic inequality. Hence, the most logical inference is that the current model of growth may increase income disparities due to structural skill barriers, making option (b) the correct answer.