MICROPROPAGATION OF TWO VARIETIES OF APPLE (Malus domestica Borkh) USING SHOOT EXPLANTS

Abstract

Apple is a perennial Pomaceous fruit tree commonly grown in the northern temperate zones. Apples produced from seed are mostly interspecific hybrids so that it is difficult to produce true-to-type cultivars from seeds. The objective of this study was to develop micropropagation protocol for MM106 and Anna varieties using shoot explants. Among different concentrations of BAP in combination with IBA, 96.7% (29 out of 30) MM106 shoot explants were initiated on MS medium containing 1.0 mgl^-1 BAP in combination with 0.1 mgl^-1IBA whereas 93.3% (28 out of 30) Anna explants were initiated on 1.5 mgl^-1BAP in combination with 0.1 mgl^-1IBA.The maximum mean number of shoots (6.67 ± 0.58) per explant was obtained from MM106 variety on MS medium containing 1.5 mgl^-1BAP in combination with 0.01 mgl^-1IBA and 0.5 mgl^-1GA₃. For Anna 6.33 ± 0.0 mean number of shoots were produced on the multiplication medium containing 2.0 mg/l BAP, 0.5 mg/l GA₃ and 0.01 mg/l IBA. Numbers of subcultures were found to affect the rate of shoot multiplication. The maximum mean shoot number per explant (8.70 ± 2.77) of MM106 was obtained at the fifth subculture (20 weeks) while that of Anna (7.63 ± 0.59) was obtained at the second subculture (8 weeks). The highest number of roots per explant (5.7 ± 0.69) was obtained from MM106 and 6.25 ± 0.50 from Anna on half strength MS medium containing activated charcoal and supplemented with 1.0 and 2.0 mgl^-1 IAA, respectively. The survival rate of the acclimatized plantlets was 91.4% (127 from 140) and 65.7% (92 from 140) for MM106 and Anna varieties, respectively.