Effect of Plant Growth Regulators on Micropropagation of Mulberry (Morus Alba L.) Through in Vitro Culture of Shoot Tip and Nodal Explants

Abstract

The mulberry tree represents different ideas among different cultures. It signifies the sign of nature, food, growth and for some death. Mulberry belongs to the genus Morus of the family Moraceae with chromosome no. 2n = 308. It is conventionally propagated through vegetative means. But, this approach of propagation is not feasible for commercial production of plants and has at more time the chances of reduction yield. Therefore, the availability of quality planting material is of urgent need. Recently, there has been a promising approach for mulberry multiplication at large scales through tissue culture because it generates a large number of contamination free plantlets in a minimum space and time. Use of mercuric chloride o.1 % and ethanol 70 % were found to be the best instead of their alone for higher explant survival with low contamination percentage in established cultures. The earliest callus initiation (25.67 days) after inoculation was noted under 2-4 D @ 4.0 mgl-1 + BAP @ 2.00 mgl-1. Minimum time of shoot initiation in the culture (19.67 days) was recorded under the treatment of BAP 3.00 mgl-1+ IBA 0.10 mgl-1, while the maximum time (28.67 days) was observed under BAP 3.00 mgl-1+ IBA 0.10 mgl-1. The minimum (26.30days) was noted under of BAP 2.00 mgl-1+ IBA .10 mgl-1. Maximum shoot length obtained (3.16 cm) was found under the treatment of BAP 3.00 + IBA 0.50 mgl- 1. Maximum percent of developed shoots obtained from the established culture (83.16) was noted under the treatment of BAP 3.00 mgl-1 + IBA 0.10 mgl-1.. Shoots per explant/ inoculums increased from 3.03 to 5.74 with treatments BAP 2.00 mgl-1 + IBA 1.00 mgl-1 cm and BAP 3.00 mgl-1 + IBA 0.10 mgl-1 respectively. The Days taken for root initiation minimum (11.66 days) was noted under IBA 2.00 mgl-1+ BAP 0.50 mgl-1 . The length of root per plantlet obtained from the established explants in the culture medium was significantly increased from 2.12 to 3.25 cm with treatments of IBA 3.00 mgl-1 + BAP 1.00 mgl-1and IBA 2.00 mgl-1 + BAP 0.50 mgl-1 respectively.