Production and rooting of etiolated cuttings of West Indian and hybrid avocado

Abstract

Etiolated cuttings of avocado cvs. 'Pollock' (West Indian) and 'Lula· (Guatemalan X West Indian hybrid) were produced and successfully rooted. Hardwood and semi-hardwood stem cuttings (18cm long, 1.5 cm diameter) of 'Pollock' and 'Lula' avocado produced new shoots with etiolated bases from lateral buds when placed San under a vermiculite/perlite medium in a closed humidified propagating bin. These new shoots (12-16cm long, with 4-6 leaves and with an etiolated stem base 4-6cm long) were severed from the original cuttings and subsequently rooted. To increase the number of new shoots (etiolated cuttings) the original stem cuttings were treated with gibberellic acid (GA3). 6-benzylamino purine (BA) and their mixtures at 50 and 100 ppm. GA3 at 100ppm produced etiolated shoots in 93% of the original stem cuttings; and treatment with BA at 50 ppm induced multiple shoot development from single buds. In 'Pollock' and 'Lula' etiolated cuttings the percentages of rooting were 50 and 66, respectively; non-etiolated cuttings failed to root under mist. Application of indolebutyric acid (IBA) at 3000ppm improved the rooting of etiolated cuttings in the two cultivars by 16-17%, i.e. the percentage of rooting in 'Pollock' and 'Lula' increased to 66 and 83, respectively. The results of investigation provide a technique for propagating West Indian ('Pollock') and hybrid ('Lula' avocado by cuttings.