Question

Normally broadcasting method of seed sowing is followed for small seeds and identify the species for which the broadcasting is suitable

• A. Melia dubia
• B. Tectona grandis
• C. Acrocarpus fraxinifolius
• D. Casuarina equisetifolia

Hint:

Small seeds = Broadcast (e.g., Casuarina, Adina, Eucalyptus).
Large seeds = Dibble (e.g., Teak, Sal, Oaks).
Dust-like seeds are often mixed with sand before broadcasting to ensure even distribution.

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
Broadcasting is the process of scattering seeds evenly over the entire surface of a nursery bed or plantation site. It is most suitable for very small, light seeds that do not require deep burial.

Step 2: Detailed Explanation:

• Seed Size vs. Sowing Method: Large seeds (like Teak) are usually dibbled or planted in lines. Medium seeds are often sown in drills. Tiny, "dust-like" or winged seeds are best broadcast.

• Casuarina equisetifolia (D): The seeds (technically samaras) of Casuarina are extremely small and light (approx. 600,000 to 1,000,000 seeds per kg). In nursery management, these are broadcast on the surface of primary sand beds and then lightly covered with a thin layer of sand. Line sowing or dibbling would be practically impossible due to their size.

• Comparison with other options: - Teak (B): Large, hard drupes. Always dibbled. - Melia dubia (A): Fleshy fruits with relatively large stones. - Acrocarpus (C): Small seeds, but often drill-sown for better spacing control compared to the very fine Casuarina seeds.

• Precautions: Broadcast beds must be protected from ants and wind, as the tiny seeds are easily displaced.

Step 3: Final Answer:
Among the given species, Casuarina equisetifolia is the one for which the broadcasting method is most commonly and appropriately used.