Micropropagation of Two Tropical Conifers: Pinus Oocarpa Schiede and Cupressus Lusitanica Miller

Abstract

Plantlet regeneration of 2 tropical conifer species (Pinus oocarpa Schiede and Cupressus lusitanica Miller) was accomplished using expiants obtained from embryonic and seedling tissues. Adventitious buds were induced on P. oocarpa cotyledonary expiants obtained from 7- and 10-day-old seedlings. The expiants were placed on a defined nutrient medium containing cytokinin alone or in combination with an auxin for 21 days and then were transferred to a culture medium without hormones. Further bud development and shoot elongation occurred in this medium. Hypocotylary expiants obtained from 4-week-old C. lusitanica seedlings were cultured for 21 days on nutrient medium supplemented with various cytokinins alone or in combination with an auxin. Further development of buds and subsequent shoot elongation occurred when the expiants were transferred to nutrient medium without growth regulators. Elongated shoots of both species were rooted after treatment with an auxin. Successful transfer of the rooted plantlets to soil under greenhouse conditions has been achieved for both species.