Genetic difference in adventitious rhizogenesis in Albizia procera Benth. with IBA treatment

Variable adventitious rhizogenesis of juvenile shoot cuttings was observed in seven half-sib families (TP-1, BAN-1, AN-3, JR-3, SL-16, UM-3, and UM-5) of Albizia procera Benth. Treatment with IBA invariably promoted sprouting by 8%, adventitious rooting by 218%, root number by 869%, and root length by 36.4% compared with the control. Interaction between families and IBA treatment significantly enhanced sprouting and root length in BAN-1, JR-3, UM-3, and UM-5, and root number in all families, but had a significant suppressive effect on sprouting in AN-3. Treatment with IBA increased family heritability (h _f ²) 1.38-fold for sprouting, 2.86-fold for adventitious rooting, and 10.86-fold for root number, but reduced family heritability by a factor of 8.25 for root length. Thus, direct genetic effects seem to have strongly affected sprouting and adventitious rooting, with IBA playing an auxiliary role, but had little effect on root number and length, for which IBA had a dominant regulatory role.