Mulberry is commercially cultivated for its foliage to feed silkworms.
Usually when tender mulberry cuttings and mulberry varieties which have poor rooting ability are planted, most of the nutrients present in the cuttings will be utilized by the sprouting parts leaving less nutrients for root development.
Due to this imbalance, the roots fail to develop proportionately, and lead to the death of the saplings.
Rooting hormone
However, if the tender cuttings are treated with rooting hormone, the hormone will inhibit the growth of the sprouting and allows the root to grow proportionately, thus preventing the death of the plant.
Naphthyl acetic acid (NAA) and Indole acetic acid (IAA) are synthetic hormones commonly used for improving rooting in mulberry cuttings. NAA is cheaper as compared to IAA.
By using these rooting hormones, even the immature cuttings, which are normally not fit for planting, can be made useful for the purpose.
Lower ends of the prepared cuttings should be dipped up to a depth of 1 cm in 10,000 ppm (1 mg/ liter gives solution, therefore, 10 g/ liter gives 10,000 ppm solution) solution on NAA or IAA for 3-5 seconds and then these hormone treated cuttings are planted.
Hormone solution
To prepare 10,000 ppm of hormone solution, dissolve 10 gms of the hormone powder in 250 ml of alcohol (Methanol/ Ethanol/ Sprit/ Arrack) and then the stock solution is slowly added to 750 ml of water to get a final volume of one litre.
Mixing the stock solution with water should be very slow, with constant stirring so that the hormone is not precipitated. If precipitation is observed, the solution is not useful for cutting treatment.
If the cuttings are dipped for more than five seconds in the hormone solution, surface burning/ drying of cuttings takes place.
(Dr. N. B. Chowdary, Scientist-C and Dr. B. B. Bindroo, Director, Central Sericultural Research and Training Institute, Central Silk Board , Ministry of Textiles, Govt. of India, Srirampura, Mysore – 570 008, Karnataka, email: >balaji_narishetty@yahoo.com , Mobile: 09449994014).
