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In Vitro Studies On Explants And Field Studies On Mycorrhizal Associations Of Pinus Cribaea Mor. Var Hondurensis Barr. And Golf.

By

Abstract

Multiple shoot induction from embryos and shoot tip explants was
investigated as a possible means for inass propagation of Pinus caribaea Mor. Var.
Hondurensis. A mean of eleven (1 1) shoots per embryo was obtained whilc a
mean of 12 and 17 shoots were obtained for one-week old and five-week old
shoot tips respectively. l'he concentration of Benzyllilnino purine (BAP)
influenced bud formation and the development and elongation of s h ~ o t sw ere
enhanced by elimination of BAP, reduction of sucrose concentration as well as the
addition of activated charcoal to the medium. Growth of callus and possible
plantlet regeneration thereof; callus greening, growth habits and anthocyanin
production were also studied by manipulating the hormonal composition of the
medium. Occurrence of callus variarts during subcultures and its ~ncchanism
were also investigated.
Best growth of callus was achieved in Von Arnold and Eriksson, (AE)
(1981) medium containing 2mgl-' NAA alone and also in the interaction 2ingl-'
113A x 0.5mgl~B' AP. Multiple shoot induction was not achieved. However, callus
greening (associated with shoot initialion) was best pronloted by the main effects
of kinetin (5mgl-'); BAP (5mgle') and NAA (2mgl-'). Two forms of callus growth
habits were observed - loose friable and compact calluses. In NAA x kinctin