Sanitation of sweet orange through micrografting

Abstract

Micrografting technique was used for the development of virus free nursery in Sweet Orange cv. Blood Red Malta. The micrografting was carried out using 11- 20 days old etiolated seedlings of Rough Lemon, Sour orange, Carrizo and Karna Khatta rootstocks. An apical meristem (1-2 mm) having 3-leaf primordial (0.3-0.5 mm) was placed on aseptically grown rootstocks making an inverted ‘T’ incision in vitro. Micrografts were inoculated on MS media added with auxins. Highest grafts success (60%) was recorded when apical meristems grafted on 13 days old Carrizo seedlings were used as rootstock. Scion treated with 2,4-D at 3.0 mg/l exerted maximum positive effect on the success of STG (70%). Successful micrografts were hardened under controlled conditions and further shifted in insect proof net house to develop disease free mother progeny.