UPSC MainsAGRICULTURE-PAPER-I201510 Marks150 Words
Q18.

What are objectives of seed testing? Write the testing procedure adopted in paddy and wheat crops.

How to Approach

This question requires a structured response outlining the objectives of seed testing and detailing the procedures for paddy and wheat. The approach should be to first define seed testing and its importance, then list the key objectives. Following this, specific testing procedures for paddy and wheat should be elaborated, highlighting differences where applicable. A concluding summary reinforcing the significance of seed testing is necessary. A table comparing key tests for both crops would be beneficial for clarity.

Model Answer

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Introduction

Seed testing is a critical component of ensuring food security and agricultural productivity. It's the process of evaluating seed quality to determine its genetic purity, physical purity, and physiological health. With India aiming to increase agricultural output and improve farmer incomes, the quality of seeds planted is paramount. The Seed Act, 1966, and subsequent amendments, emphasize the importance of quality seed production and distribution. Recent initiatives like the Seedling India project, focused on improving seed availability and quality, underscore the continuing relevance of seed testing.

Objectives of Seed Testing

The primary objectives of seed testing are to:

  • Genetic Purity: Confirming the seed is of the stated variety and hasn't undergone genetic contamination.
  • Physical Purity: Assessing the absence of weed seeds, inert matter, and other contaminants.
  • Seed Health: Detecting the presence of seed-borne diseases.
  • Seed Vigor: Evaluating the seed's ability to germinate and establish a healthy seedling under stress conditions. This goes beyond just germination percentage.
  • Germination Percentage: Determining the percentage of seeds that germinate under standard laboratory conditions.
  • Seed Size & Weight: Assessing these parameters to ensure uniformity and predict plant performance.

Testing Procedures: Paddy

Seed testing for paddy (rice) involves several key procedures:

  • Physical Purity Test: Visual examination and sieving to remove impurities.
  • Moisture Content: Measured using a moisture meter. Ideal moisture content is typically around 14%.
  • Germination Test: Conducted on paper towels or in sand at 30°C. Germination percentage is assessed after 7 days.
  • Seed Health Test: Surface sterilization followed by incubation on agar medium to detect seed-borne diseases like Rhizoctonia solani and Pyricularia oryzae.
  • Vigor Test: Accelerated aging test (pre-soaking seeds and drying them rapidly) to assess vigor.

Testing Procedures: Wheat

Seed testing for wheat follows a similar framework but with some variations:

  • Physical Purity Test: Sieving and visual examination.
  • Moisture Content: Measured using a moisture meter. Ideal moisture content is typically around 12%.
  • Germination Test: Conducted on paper towels at 25°C. Germination percentage is assessed after 7 days.
  • Seed Health Test: Surface sterilization and incubation on agar medium to detect diseases like Tilletia tritici (bunt) and Fusarium species.
  • Tetrazolium Test: A rapid test to assess seed viability by assessing dehydrogenase activity.
  • Seedling Growth Test: Seeds are germinated in pots and seedling vigor assessed by root and shoot length.
Test Paddy Wheat
Germination Temperature 30°C 25°C
Seed Health Detection Rhizoctonia, Pyricularia Tilletia, Fusarium
Vigor Test Accelerated Aging Tetrazolium & Seedling Growth

Importance of Standards

The Seed Act, 1966, mandates adherence to minimum standards for seed quality. The Seed Quality Control (Regulation) Order, 1988, further details these standards. Accredited seed testing laboratories play a vital role in ensuring these standards are met.

Conclusion

Seed testing is indispensable for maintaining the quality of seeds, which directly impacts crop yields and farmer livelihoods. The procedures for paddy and wheat, while sharing core principles, have specific adaptations to address the unique characteristics and disease pressures of each crop. Continuous advancements in testing methodologies and stricter quality control measures are crucial for ensuring a sustainable and productive agricultural sector in India. Further investments in accredited seed testing laboratories and farmer awareness programs are vital.

Answer Length

This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.

Additional Resources

Key Definitions

Seed Vigor
Seed vigor refers to the ability of seeds to germinate and produce strong, healthy seedlings under less-than-ideal conditions. It’s more than just germination percentage; it reflects the seedling’s overall health and resilience.
Physical Purity
Physical purity refers to the absence of extraneous matter like weed seeds, chaff, and other non-seed material in a seed lot. It is assessed through visual inspection and sieving techniques.

Key Statistics

India’s seed market is estimated to be around $4.5 billion (Knowledge cutoff: 2023).

Source: Various industry reports

The Seed Act, 1966, mandates a minimum germination percentage of 80% for most crops.

Source: The Seed Act, 1966

Examples

Disease Detection Example

In paddy, the seed health test can detect <i>Pyricularia oryzae</i>, the causal agent of blast disease, preventing widespread crop losses if infected seeds are planted.

Wheat Bunt Disease

The presence of <i>Tilletia tritici</i> in wheat seeds leads to bunt disease (stinking smut), which can significantly reduce grain quality and yield. Seed testing helps identify and eliminate such seeds.

Frequently Asked Questions

Why is seed testing important for small farmers?

Seed testing ensures farmers receive quality seeds, reducing crop failures and improving yields, which is particularly crucial for small farmers with limited resources.

What is the difference between germination percentage and seed vigor?

Germination percentage measures the proportion of seeds that sprout. Seed vigor assesses the overall health and strength of the seedling emerging from those seeds – a seed can germinate but the seedling might be weak.

Topics Covered

AgricultureSeed ScienceBotanySeed QualitySeed TestingPaddy CultivationWheat Cultivation