🌱 Propagation of Host Plants: Cutting and Layering

Propagation is the process of multiplying plants using natural or artificial methods. In sericulture, the proper propagation of host plants like Mulberry, Castor, Som, and Soalu is crucial, as they serve as the sole food source for silkworms. Two common and effective vegetative propagation techniques used for these plants are Cutting and Layering.

✂️ 1. Propagation by Cutting

Definition:
Cutting is a method of asexual propagation in which a piece of the stem, root, or leaf is cut from the parent plant and grown into a new plant.

✅ Key Features:

1. Commonly used in Mulberry and Castor.

2. Ensures genetic uniformity (clones of parent).

3. Faster growth and high success rate.

🌿 Types of Cuttings:

1. Stem Cuttings (most common for host plants)

2. Root Cuttings

3. Leaf Cuttings (rare in sericulture)

📌 Procedure (Stem Cutting):

1. Select a healthy, mature plant.

2. Cut a stem piece (15–20 cm long) with 3–4 buds.

3. Dip the base in a rooting hormone (optional).

4. Plant it in moist soil or nursery beds.

5. Water regularly and keep in partial shade. Success rate increases in the monsoon or early spring due to high humidity.

🌳 2. Propagation by Layering

Definition:
Layering involves inducing root formation on a still-attached part of the plant, which is later detached after rooting.

✅ Key Features:

1. Used for plants with flexible branches, like Som and Soalu.

2. Higher rooting success than cuttings in some species.

3. Preserves the connection to the parent plant, ensuring nutrients during rooting.

🌿 Types of Layering:

1. Simple Layering (branch bent and buried in soil)

2. Mound Layering (stem covered with soil at the base)

3. Air Layering (used in woody plants)

📌 Procedure (Simple Layering):

1. Select a healthy, low-growing branch.

2. Wound the branch slightly where it will touch the soil.

3. Bury the wounded part in soil, keeping the tip exposed.

4. Secure it with a peg or stone.

5. After rooting, cut from the parent and transplant. Layering works best during monsoon or early spring when the soil remains moist.

Summary Table

Feature	Cutting	Layering
Root development	Detached stem grows roots	Roots while still attached
Use in host plants	Mulberry, Castor	Som, Soalu
Success rate	High (with care)	Very high
Rooting hormone use	Often used	Rarely needed
Suitable season	Monsoon or Spring	Monsoon or Spring

🔁 Importance in Sericulture

1. Ensures availability of nutritious leaves for silkworms.

2. Enables mass multiplication of elite plant varieties.

3. Reduces dependency on seeds which may have variable traits.

Understanding and applying the correct propagation methods like cutting and layering help ensure the sustainable cultivation of host plants vital to sericulture. These methods are simple, cost-effective, and ensure genetic fidelity, making them ideal for farmers, students, and sericulturists.

📚 References

1. Ganga, G., & Sulochana, C. (1997). An Introduction to Sericulture. Oxford & IBH Publishing.

2. FAO. (2009). Propagation Techniques for Mulberry Plants. FAO Manual

3. Assam Sericulture Department – https://sericulture.assam.gov.in